JP2005525705A - Improvements for contactless power transmission - Google Patents

Abstract

Disclosed are systems and methods for delivering power without the need for direct electrical contact. A power source, and at least one conductor that generates an electromagnetic field when current flows therethrough and a substantially laminar charging surface having a charging area defined within a periphery of the surface, wherein at least one The at least one conductor is arranged such that the electromagnetic field lines generated by the conductor are substantially parallel to the plane of the surface within the range of the charging area, or within an angle range of at least 45 ° or less with respect to the surface. A primary unit is provided and at least one secondary device is provided that includes at least one conductor wound around the core. The electromagnetic field spreads over the charging area and is substantially parallel or nearly parallel to the charging area, so coupling with a thin secondary device such as a mobile phone or the like can be in various directions in the charging area. Will be improved.

Description

  This application is filed on British Patent Application No. 0210886.8 filed on May 13, 2002, United Kingdom Patent Application No. 0213024.3 filed on October 28, 2002, and filed on December 6, 2002. Claiming priority based on United Kingdom Patent Application No. 02284255.5 and US Patent Application No. 10 / 326,571, filed December 20,2002. The entire contents of all these prior patent applications are incorporated herein by reference.

  The present invention relates to a new apparatus and method for transmitting power in a contactless manner.

  Many of today's portable devices incorporate rechargeable “secondary” batteries, saving the user the cost and inconvenience of having to purchase new batteries on a regular basis. Examples of these devices include cell phones, laptop computers, Palm 500 series of personal digital assistants, electric razors, and electric toothbrushes. In some of these devices, the battery is recharged by electromagnetic induction rather than a direct electrical connection. Examples include Brown's Oral B Plak control electric toothbrush, Panasonic's Digital Cordless Phone Solution KX-PH15AL, and Panasonic's multi-head shaving ES70 / 40 series.

  Each of these devices typically takes power from a power outlet, car cigarette lighter power source, or other power source and converts it into a form suitable for charging a secondary battery. Have There are a number of problems associated with the conventional means of feeding and charging these devices:

  -The characteristics of both the battery in each device and the means for connecting to the battery vary significantly from manufacturer to manufacturer and from device to device. Thus, a user who owns multiple such devices must own multiple different adapters. When the user goes on a trip, the user will have to carry the collected charger if he wishes to use these devices during the trip.

  Adapters and chargers are inconvenient because they often require the user to plug a small connector into the device or to place the device precisely on the stand. If the user fails to push or install the device and the device runs out of power, the device becomes useless and important data stored locally on the device may even be lost.

  Furthermore, most adapters and chargers must be plugged into a power socket, so if multiple units are used at the same time, they occupy the plug strip space, resulting in tedious and confusing wire tangles.

  In addition to the problem of the conventional device recharging method, the device having an open type electrical contact has a practical problem. For example, the device cannot be used in a moist environment because it can corrode or short-circuit the contacts, and it cannot be used in a flammable gas environment because it can cause electrical sparks.

  Chargers using inductive charging eliminate the need to use open electrical contacts, thus allowing the adapter and device to be sealed and used in a moist environment (for example, the electric toothbrush described above Designed to be used in the bathroom.) However, such a charger has all the above problems. For example, the device still needs to be accurately placed on the charger so that the device and charger are in a predetermined relative position (see FIGS. 1a and 1b). Adapters are specially designed for the manufacture and model of certain devices and can only charge one device at a time. As a result, the user must continue to own and manage the collection of various adapters.

  There are also universal chargers (such as the Maha MH-C777 Plus Universal Charger) where battery packs of various shapes and characteristics can be removed from the device and charged using a single device. These universal chargers eliminate the need to have different chargers for each device, but first remove the battery pack and then adjust the charger to place the battery pack into the charger or with the charger. This brings more inconvenience to the user in the sense that it needs to be aligned relatively accurately. Moreover, it takes time to determine the exact pair of battery pack metal contacts that the charger must use.

  Providing means for contactless battery charging so that when the device is installed in the primary cavity, the primary induction coil is aligned with the horizontal induction coil of the secondary device is disclosed in US Pat. No. 3,938,018. It is known from the "Electromagnetic induction charging system". This cavity ensures the relative fine alignment required to ensure that excellent coupling is achieved between the primary and secondary coils using this design.

  A contactless battery charging system is also known from US Pat. No. 5,959,433, “Universal electromagnetic induction battery charger system”. The disclosed battery charger includes a single charging coil that produces magnetic flux lines that induce current in a battery pack belonging to a cell phone or laptop computer.

  An electronic device charging device including a pair of coils is known from US Pat. No. 4,873,677, “Electronic Device Charging Device”. This pair of coils is designed to operate in anti-phase and the flux lines are coupled from one coil to the other. An electronic device such as a watch is placed on these two coils to receive power.

  An electromagnetic induction charger for charging a rechargeable battery is known from US Pat. No. 5,952,814, “Electromagnetic induction charger and electronic device”. Since the shape of the outer casing of the electronic device matches the inner shape of the charger, it is possible to accurately align the primary coil and the secondary coil.

  A substitute battery pack that is recharged in an electromagnetic manner is known from US Pat. No. 6,206,115 “Battery substitute pack”.

  Means for transmitting electric power to the conveyor electromagnetically is known from International Patent Publication No. 00/61400 “Apparatus for transmitting electric power to electromagnetic induction”.

  A system for electromagnetically feeding an electric vehicle from a flat primary side of a road to an electric vehicle is known from WO 95/11545.

  To overcome the limitations of the electromagnetic induction power transfer system that requires the secondary device to be axially aligned with the primary unit, as an obvious solution, the primary unit has the ability to radiate an electromagnetic field over a large area. It is proposed to use a single electromagnetic induction power transfer system (see FIG. 2a). The user need only install one or more devices to be recharged within the primary unit range, and does not need to install the devices accurately. For example, this primary unit is constituted by a coil surrounding a wide area. As current flows through the coil, an electromagnetic field is created that extends over a large area and the device may be placed anywhere in this area. Even though it is theoretically feasible, this method has a number of drawbacks. First, the intensity of electromagnetic radiation is suppressed by regulatory limits. That is, this method can only support a limited rate of power transmission. In addition, many objects are affected by the presence of a strong magnetic field. For example, data stored on a credit card is destroyed, and metal objects are induced internally with eddy currents that cause undesirable heating effects. Furthermore, if a secondary device with a conventional coil (see FIG. 2a) is installed in contact with a metal plate such as a copper surface of a printed circuit board or a metal can of a battery, the coupling is It can be significantly reduced.

  In order to prevent the generation of a strong magnetic field, it is proposed to use an array of coils (see FIG. 3) and operate only the necessary coils. This method has been published in the journal of the Japan Society of Applied Magnetics (issued on November 29, 2001) under the title "Basic study on the coil shape of a desk-type non-contact power transmission system". When implementing the concept of multiple coils, the detection mechanism detects the relative position of the secondary device with respect to the primary unit. The control system then activates the appropriate coil to distribute power to the secondary device in a localized manner. This method provides a solution to the problems listed above, but solves it in a complex and expensive manner. The degree to which the primary field can be localized is limited by the number of coils and hence the number of drive circuits used (ie, the “resolution” of the primary unit). The costs incurred with multiple coil systems greatly limit the commercial application of this concept. Also, the non-uniform magnetic field distribution is a drawback. When all coils are actuated in the primary unit, they are equivalent to large coils where the magnetic field distribution is minimized at the center of the coil.

  Another scheme is outlined in US Pat. No. 5,519,262 “Short Range Power Coupling System”, in which the primary unit is composed of a number of thin induction coils (or alternatively capacitive plates). Are aligned from one end of the flat plate to the other, producing a number of vertical magnetic fields that are driven in a phase-shifted manner so that sinusoidal activity travels on the plate. The receiver has two vertical magnetic field pickups arranged so that power can always be collected from at least one pickup irrespective of its position on the plate. This scheme also provides freedom of movement of the device, but has the disadvantages that it requires a complex secondary device, the resolution is fixed, and the magnetic flux return path goes through the air.

  None of the prior art solutions can adequately solve all of the above problems. It would be advantageous to have a cost-effective solution to implement with the ability to transmit power to a portable device using all of the following features:

  Versatility: A single primary unit can supply different secondary devices with different power requirements, thereby eliminating the need to collect different adapters and chargers.

  Convenience: A single primary unit may install the secondary device anywhere near the active state, thereby accurately plugging or installing the secondary device into the adapter or charger Is not necessary.

  Multiple loads: A single primary unit can supply power to multiple secondary devices simultaneously with their respective power requirements.

  • Flexibility for use in different environments: a single primary unit can supply power to the secondary device so that direct electrical contacts are not required, thereby enabling the secondary device and the primary unit As such, it can be used in wet environments, gas environments, clean environments, and other abnormal environments.

  Low electromagnetic radiation: The primary unit distributes power in such a way as to minimize the strength and size of the generated magnetic field.

  Furthermore, it can be seen that the number of portable devices is increasing, and all portable devices need a battery to supply power. Primary batteries, or batteries of primary batteries, are discarded once they are used, so they are expensive and not environmentally friendly. Secondary batteries or batteries can be recharged and used repeatedly.

  Most portable devices have containers for batteries of industry standard size and voltage such as AA, AAA, C, D and PP3. This leaves room for the user to choose between different types of primary and secondary batteries. When depleted, the secondary battery is typically removed from the device and placed in a separate recharge unit. Alternatively, some portable devices have a built-in recharge circuit that can be recharged in place after the device is plugged into an external power source.

  It is inconvenient for the user to remove the battery from the device to recharge or plug the device into an external power source to charge in place. It would be highly desirable to be able to recharge the cell using some non-contact means without having to remove the battery or plug in the device.

  Some portable devices, such as Brown's Oral B Plak control toothbrush, have the ability to receive power electromagnetically from a recharger. Such portable devices typically have a custom dedicated power receiving module built into the device, and this receiving module works with an internal standard battery or battery (removable or non-removable).

  However, the user simply installs the inductive rechargeable battery or battery and then places the device on the inductive recharger so that the inductive rechargeable battery or battery is in place. Any portable device that can be recharged with an industry standard battery size can be converted to an electromagnetic induction rechargeable device for ease of use.

  Examples of the prior art include US Pat. No. 6,208,115 which discloses an alternative battery pack that is rechargeable in an electromagnetic induction manner.

According to a first aspect of the present invention, there is provided a system for transmitting power without the need for direct electrical contact,
i) The system comprises a primary unit comprising a charging surface that is substantially laminar and at least one means for generating an electromagnetic field, the means being in a predetermined surface that is in or parallel to the charging surface. The charge area is two-dimensionally distributed in a predetermined area so as to define at least one charging area of the charging surface that is substantially the same area as the area, and the charging area is wide and long on the charging surface. This means that when a predetermined current is supplied to the means and the primary unit is effectively electromagnetically shielded, the electromagnetic field generated by the means is measured parallel to the direction of the electromagnetic field lines. When averaged over a quarter length of the charging area, it enters an angle range of 45 ° or less with respect to the charging surface in the vicinity of the charging surface and is distributed two-dimensionally on the charging surface. Configure to have electromagnetic field lines. Is, the means is shorter than either the height measured in a substantially vertical direction of the width and length of the charging region relative to the charge area,
ii) the system comprises at least one secondary device comprising at least one electrical conductor;
When at least one secondary device is placed in or near the charging area of the primary unit, the electromagnetic field lines couple with at least one conductor of the at least one secondary device and induce a current flowing through the conductor. To do.

  According to a second aspect of the present invention, a primary unit is provided that transmits power without the need for direct electrical conductive contact, which primary unit generates an electromagnetic field with a charging surface that is substantially layered. At least one means for defining, wherein the means defines at least one charging area of the charging surface that is substantially as wide as the predetermined area that is on or parallel to the charging surface. The charging area has a width and a length on the charging surface, and this means is supplied with a predetermined current, and the primary unit is effectively electromagnetically When shielded, near the charging surface when the electromagnetic field generated by the means is averaged over a quarter length of the charging area measured parallel to the direction of the electromagnetic field lines. 45 ° or more with respect to the charging surface And is configured to have electromagnetic field lines distributed two-dimensionally on the charging surface, the means having a height measured substantially perpendicular to the charging area of the charging area. Shorter than either width or length.

According to a third aspect of the invention, there is provided a method of non-conductively transferring power from a primary unit to a secondary device, the primary unit generating at least a charging surface and an electromagnetic field that are substantially layered. A means, the means being distributed in a predetermined area that is at or parallel to the charging surface so as to define at least one charging area of the charging surface, the charging area being The charging area has a width and length on the charging surface, and the means is such that the height measured substantially perpendicular to the charging area is the width of the charging area. And the secondary device has at least one electrical conductor,
i) The electromagnetic field generated by the means when powered by a predetermined current and measured when the primary unit is effectively electromagnetically shielded is the charge field measured parallel to the direction of the electromagnetic field lines. At least one when averaged along the length of the quarter enters an angular range of 45 ° or less to the charging surface in the vicinity of the charging surface and averaged over the charging area Having electromagnetic field lines distributed two-dimensionally on the charging area;
ii) The electromagnetic field couples with the secondary device conductor when the secondary device is placed in or near the charging area.

  According to a fourth aspect of the present invention there is provided a second apparatus for use with the system of the first aspect, the unit of the second aspect, or the method of the third aspect, the second apparatus comprising: , Including at least one electrical conductor and having a shape factor that is substantially lamellar.

  In the context of the present application, the term “laminar” refers to a geometric property in the form of a lamina or lamina. The lamina or lamina may be substantially flat or curved.

  The primary unit includes an integral power source for at least one means for generating an electromagnetic field, or a connector or the like is provided that allows at least one means to be connected to an external power source.

  In some embodiments, the means for generating an electromagnetic field has a height that is less than half the width or half of the length of the charging area, and in some embodiments this height is one of the width of the charging area. / 5 or shorter than 1/5 of the length.

  At least one electrical conductor of the second device is wrapped around a core that serves to concentrate the magnetic flux therein. In particular, the core (if provided) provides a path of minimum resistance to the magnetic field flux lines generated by the primary unit. The core may be an amorphous magnetically permeable material. In some embodiments, it is not necessary to use an amorphous core.

  If an amorphous core is provided, preferably the amorphous magnetic material is not annealed, i.e., remains substantially cast. At least 70% of this material is not annealed, and preferably at least 90% is not annealed. This is because annealing tends to make amorphous magnetic materials brittle, which is disadvantageous when contained in devices such as mobile phones that are handled violently by being dropped accidentally. In a particularly preferred embodiment, the amorphous magnetic material is provided in the form of a flexible ribbon composed of one or more layers or one or more of the same or different amorphous magnetic materials. Suitable materials include iron, boron, and alloys containing silicon or other suitable material. The alloy is melted and then rapidly cooled (“quenched”) to the extent that it does not have time to become liquid when solidified, leaving the alloy in a glassy amorphous state. Suitable materials include Metglas® 2714A and similar materials. Permalloy or mu metal may be used.

  If provided, the core of the secondary device is preferably a highly permeable core. The permeability of the core is preferably at least 100, more preferably at least 500, most preferably at least 1000, with a size of at least 10,000 or 100,000 being particularly advantageous.

  The at least one means for generating the electromagnetic field may be, for example, a wire in the form of a wire or a printed strip, may be in the form of a suitably structured conductive plate, or may be constituted by a suitable array of conductors. May be. The preferred material is copper, but other conductive materials, generally metals, are used as needed. It should be understood that the term “coil” is intended herein to encompass any suitable electrical conductor that forms an electrical circuit through which current flows and thereby generates an electromagnetic field. It is. In particular, the “coil” does not have to be wound around a core or something like a core, but may be a simple loop or a complex loop, or an equivalent structure.

  Preferably, the charging area of the primary unit is large enough to accommodate the conductors and / or cores of the secondary device in a plurality of positions. In one particularly preferred embodiment, the charging area is large enough to accommodate the secondary device conductors and / or cores in any position. In this way, power transfer from the primary unit to the secondary device requires that the conductor and / or core of the secondary device be aligned in a specific direction when the secondary device is installed on the charging surface of the primary unit. It is realized without doing.

  The substantially unitary charging surface of the primary unit may be substantially planar, or may be curved for incorporation into a predetermined space, such as a compartment such as a car dashboard, or other structure. But you can. Particularly preferably, the means for generating an electromagnetic field does not protrude or protrude upwards or downwards from the charging surface.

  The main characteristic of the means for generating an electromagnetic field in the primary unit is measured when the primary unit is effectively electromagnetically shielded (ie when the secondary device is not present at or near the charging surface). The electromagnetic field lines generated by this means are two-dimensionally distributed on at least one charging area and in the vicinity of the charging area (eg less than the height or width of the charging area) Into the angle range of 45 ° or less with respect to the charging area over the length of a quarter of the charging area measured in a direction approximately parallel to the charging area. In this regard, the measurement of the electromagnetic field lines should be understood as a measurement of the electromagnetic field lines when averaged over a quarter length of the charging area, not an instantaneous point measurement. . In some embodiments, the electromagnetic field lines fall within an angular range of 30 ° or less, and in some embodiments, are substantially parallel to at least the central portion of the charging area. This is clearly different from prior art systems where the electromagnetic field lines are substantially perpendicular to the surface of the primary unit. By generating an electromagnetic field that is approximately parallel to the charging area, or having an at least significant decomposition component that is parallel to the charging area, the angular change of the electromagnetic field is within the plane of the charging area or The electromagnetic field can be controlled to be parallel, which helps to prevent the field from generating a steady zero that reduces charging efficiency when the secondary device on the charging surface is in a particular position. The direction of the electromagnetic field lines is rotated in a range of a complete circle or a partial circle in one direction or both directions. Alternatively, this orientation induces “fluctuation” or variation, or can be switched between two or more orientations. In a more complicated structure, the direction of the electromagnetic field lines changes as a Lissajous pattern or the like.

  In some embodiments, the electromagnetic field lines are substantially parallel to each other over a given charging area, or are substantially parallel to each other at a given time and in the plane of the charging area, or It has at least a decomposition component that is parallel to the plane.

  One means for generating an electromagnetic field preferably functions to generate an electromagnetic field in more than one charging area, and more than one means preferably functions to generate an electromagnetic field in only one charging area. In other words, there may be no one-to-one correspondence between the means for generating an electromagnetic field and the charging area.

  The secondary device may employ a substantially flat shape factor with a core thickness of 2 mm or less. When using materials such as one or more amorphous metal sheets, the core thickness can be reduced to 1 mm or less for applications where size and weight are important. See Figure 7a.

  In a preferred embodiment, the primary unit includes a pair of conductors having linear sections that are substantially parallel to each other and having adjacent coplanar windings, thereby relative to the plane of the windings. A substantially uniform electromagnetic field can be generated that extends substantially parallel or within an angular range of 45 ° or less, but substantially perpendicular to the parallel sections.

  The windings in this embodiment are generally formed in a spiral shape and consist of a series of turns having substantially parallel straight sections.

  Advantageously, the primary unit includes a pair of first and second conductors superimposed in a substantially parallel plane, and the substantially parallel linear section of the first pair is substantially equal to the second pair of Driving the first and second conductor pairs to generate a combined electromagnetic field that is disposed substantially perpendicular to the generally parallel straight section and rotates in a plane that is substantially parallel to the plane of the winding. And a driving circuit arranged for the purpose.

According to a fifth aspect of the present invention, there is provided a system for transmitting power in a contactless manner, the system comprising:
A primary unit comprising at least one electrical coil is provided, each coil having at least one active area, and the two or more conductors are substantially free of net instantaneous current flowing through the secondary device in a particular direction. Distributed substantially over this area so that it can be placed near a portion of this active area that is zero,
At least consisting of a conductor wound around a high permeability core so that a secondary device can be placed in the vicinity of the region of the surface of the primary unit where the net instantaneous current is substantially non-zero One secondary device is provided,
This ensures that the central axis of the winding is in the vicinity of the active area of the primary unit and is not substantially perpendicular to the plane of the active area of the primary unit, but with a conductor in the active area of at least one coil of the primary unit. When not substantially parallel, at least one secondary device has the ability to receive power using electromagnetic induction.

If the secondary device comprises an inductively rechargeable battery or battery, the battery or battery has a primary axis and can be recharged by an alternating electromagnetic field flowing through the primary axis of the battery or battery. Or the battery
A housing and external electrical connections similar in size to industry standard batteries or batteries;
・ Energy storage means,
・ Optional magnetic flux concentration means,
Power receiving means,
Means for converting the received power into a suitable form for distribution outside the cell via an external electrical connection, or for recharging the energy storage means, or both;
It comprises.

  The proposed invention is significantly different from the structure of a conventional inductive power transmission system. The differences between the conventional system and the proposed system are best explained by observing the respective flux line patterns (see FIGS. 2a and 4).

  Conventional system: In a conventional system (see FIG. 2a), there is typically a planar primary coil that generates a magnetic field with field lines emanating from the plane in the vertical direction. Secondary devices typically have circular or square coils that surround some or all of these flux lines.

  Proposed system: In the proposed system, the magnetic flux does not leave the plane as it is as shown in FIG. 2a, but travels substantially horizontally across the surface of the plane (see FIG. 4). ). Accordingly, the secondary device has an elongated winding wound around the magnetic core. See Figures 7a and 7b. When the secondary device is installed in the primary unit, the flux lines will be drawn to travel through the magnetic core of the secondary device, which is the path with the least reluctance. Thereby, the secondary device and the primary unit are efficiently combined. The secondary core and winding are substantially planarized to form a very thin component.

  In describing the present invention, specific terminology is used for the sake of clarity. However, it is not intended that the present invention be limited to the specific terms thus selected, each of which is all technically equivalent that operates in a similar manner to accomplish a similar purpose. It should be noted that this includes

  In addition, the term “charging region” as used herein refers to at least one means for generating an electromagnetic field (eg, one or more conductors in the form of a coil), or a secondary device that efficiently conducts magnetic flux. It represents a region formed by a combination of primary conductors that can be coupled. Some examples of charging zones are shown as components 740 in FIGS. 6a through 6l and 9c. “Charging area” features a distribution of conductors over a significant area of the primary unit configured such that at least one means of generating an electromagnetic field can be driven to obtain an instantaneous net flux flow in one direction It is. The primary unit may provide two or more charging areas. One charging area is distinguished from another charging area when the magnetic flux rotates at the boundary and cannot be efficiently coupled by the secondary device (as shown in FIG. 7a).

  It should be noted that the term “coil” as used in this patent application refers to all conductor structures featuring a charging area as described above. The coil includes a winding of wire, a printed track, or a plane as shown in FIG. 8e. The conductor is made of copper, gold, alloy, or other suitable material.

  This application refers to the rotation of the secondary device at multiple locations. When the secondary device is rotated, it is necessary to clarify that the axis of rotation of interest is the axis perpendicular to the plane of the charging area.

  This fundamental structural change solves many problems of conventional systems. The effects of the proposed invention are as follows.

  -Accurate alignment is not required: Secondary devices can be installed throughout the charging area of the primary unit.

  Uniform coupling: In the proposed system, the coupling between the primary unit and the secondary device is much more uniform over the charging area than the conventional primary and secondary coils. In the case of a conventional large coil system (see FIG. 2a), the electromagnetic field strength drops to a minimum value at the center of the coil in the plane of the coil (see FIG. 2b). This means that if sufficient power must be transmitted efficiently in the center, the electromagnetic field strength at the minimum value must exceed a certain threshold. The electromagnetic field strength at the maximum value is therefore excessively greater than the required threshold, which causes undesirable effects.

  Versatility: A wide variety of secondary devices with different power requirements can receive power at the same time and can be installed in the charging area on the charging surface of the primary unit.

  Increased coupling efficiency: The optional high permeability magnetic material present in the secondary device significantly increases the induced magnetic flux by providing a low reluctance path. This can significantly increase power transmission.

  Desirable shape factor of the secondary device: The geometry of this system allows the use of thin sheets of magnetic material (such as amorphous metal ribbons). That is, the secondary device can have a thin sheet shape factor, making it suitable for incorporation into the backside of a mobile phone or other electronic device. If magnetic material is used in the middle of a conventional coil, the bulkiness of the secondary device may increase.

  -Minimized electromagnetic field leakage: when more than one secondary device is present in the charging area of the primary unit, magnetic material can be used in such a way that more than half of the magnetic circuit is low reluctance material It is possible (see FIG. 4d). That is, more magnetic flux flows for a constant magnetomotive force (mmf). As the induced voltage is proportional to the rate of change of the linked magnetic flux, this results in increased power transmission to the secondary device. As the number of air gaps in the magnetic circuit is reduced and shortened, leakage is minimized because the magnetic flux is kept closer to the surface of the primary unit.

  Cost-effectiveness: Unlike the multi-coil structure, the solution of the present invention requires a simpler control system and fewer components.

  -Free rotation of the secondary device: If the secondary device is thin or optionally cylindrical (see Fig. 10), the secondary device is magnetic flux independent of rotation about its longest axis. Configured to continue to be fully coupled. This is particularly advantageous when the secondary device is a battery cell housed in another device and it is difficult to control the shaft rotation of the secondary device.

  The magnetic core of the secondary device is located in a parallel plane of other metals in or near the device, for example near a copper printed circuit board or an aluminum cover. In this example, the performance of an embodiment of the present invention is that the electromagnetic field lines through the coil of a conventional device are affected by flux rejection if the coil is placed against a metal plane (because the flux lines Because it must travel perpendicular to the plane of the coil), it is much better than the performance of a conventional core coil. In an embodiment of the invention, the flux lines travel along the core plane and thus also along the metal plane, thus improving performance. As a further advantage, the magnetic core in the secondary device of the embodiment of the present invention serves as a shield between the electromagnetic field generated by the primary unit and the object (eg, electrical circuit, battery cell) on the opposite side of the magnetic core. Can work.

  The magnetic core of the secondary device according to the embodiment of the present invention has a magnetic permeability higher than that of air, so that it acts to concentrate the magnetic flux, thereby passing through an equivalent air cross section. Captures a lot of magnetic flux. The size of the core “shape factor” (equivalent flux trapping sphere) is determined to a first order approximation by the longest planar dimension of the core. Thus, if the secondary device core of an embodiment of the present invention has a planar dimension with an aspect ratio that is not substantially square, for example, if it is a 4: 1 rectangle rather than a 1: 1 square. For example, the secondary device core captures a proportionally large portion of the magnetic flux traveling parallel to the direction of its longest planar dimension. Thus, if used in a device with a limited aspect ratio (eg, an elongated device such as a headset or pen), the performance will be significantly improved over that of a conventional coil of the same area.

  The primary unit typically comprises the following components (see FIG. 5).

  • Power source: The power source converts the mains voltage to a lower voltage DC power source. This power supply is typically a conventional transformer or switch mode power supply.

  Control unit: The control unit provides the function of maintaining the resonance of the circuit when the inductance of the means for generating the electromagnetic field changes due to the presence of the secondary device. To enable this function, the control unit is connected to a detection circuit that feeds back the current state of the circuit. The control unit is also connected to a collection of capacitors that are switched on and off as needed. If the means for generating an electromagnetic field requires more than one drive circuit, the control unit also adjusts parameters such as the phase difference or on / off time of the various drive circuits, so the desired effect Is obtained. Also, the system Q (quality factor) can be designed to function over a range of inductances so that the need for the control system is eliminated.

  Drive circuit: The drive unit is controlled by the control unit and drives the means for generating an electromagnetic field or a fluctuating current through the components of the means. There are two or more drive circuits depending on the number of independent components of the means.

  -Means for generating an electromagnetic field: This means uses an electric current supplied from the drive circuit to generate an electromagnetic field having a predetermined shape and intensity. The precise structure of this means determines the shape and strength of the electromagnetic field generated. This means comprises a magnetic material acting as a magnetic flux guide and one or more independently driven components (windings), which together form a charging area. A number of example configurations are possible, examples of which are shown in FIG.

  Detection unit: The detection unit acquires the relevant data and sends it to the control unit for interpretation.

  The secondary device typically comprises the following components as shown in FIG.

  Magnetic unit: The magnetic unit returns the energy stored in the magnetic field generated by the primary unit to electrical energy. This is typically done using a winding wound around a very high permeability magnetic core. The maximum dimension of the core typically coincides with the central axis of the winding.

  Conversion unit: The conversion unit converts the fluctuating current received from the magnetic unit into a useful form for the connected device. For example, the conversion unit uses a full-wave bridge rectifier and a smoothing capacitor to convert the fluctuating current to an unregulated DC power source. In other cases, the conversion unit is connected to a heating element or a battery charger. Also, typically a capacitor in parallel or in series with the magnetic unit is provided to form a resonant circuit at the operating frequency of the primary unit.

  In typical operation, one or more secondary devices are installed above the charging surface of the primary unit. The magnetic flux passes through at least one conductor and / or core of the secondary device, and a current is induced. Depending on the structure of the means for generating the electromagnetic field of the primary unit, the direction of rotation of the secondary device affects the amount of magnetic flux coupled.

Primary unit The primary unit is, for example,
-Flat platform or pad that can be placed on top of table and other flat surfaces-Forms built into furniture such as desks, tables, counters, chairs, bookshelves etc. A part of an exterior such as a box, a car accessory, or a power tool. ・ It exists in various forms such as a flat platform or pad that can be mounted on a wall and used in a vertical form.

The primary unit is, for example,
-AC mains outlet-Socket for car lighter-Battery-Fuel cell-Solar panel-Power is supplied from various sources such as human power.

  The primary unit may be small enough so that only one secondary device can be accommodated on the charging surface in a single charging area, or in some cases multiple secondary devices can be accommodated simultaneously in different charging areas. It may be large enough.

  The means for generating an electromagnetic field in the primary unit is driven at the mains frequency (50 Hz or 60 Hz) or higher.

  The detection unit of the primary unit detects the presence or absence of secondary devices, the number of secondary devices present, and even the presence or absence of other magnetic materials that are not part of the secondary device. This information is used to control the current delivered to the means for generating the electromagnetic waves of the primary unit.

  The primary unit and / or secondary device is substantially waterproof or explosion-proof.

  The primary unit and / or secondary device is sealed according to a standard such as IP66.

  The primary unit is a visual indicator (eg, light emitting diode, electroluminescent display, light emitting device) to indicate the current status of the primary unit, the presence or absence of secondary devices, the number of secondary devices present, or any combination thereof. Including, but not limited to, light emitting devices such as polymers, light reflecting devices such as liquid crystal displays, or MIT electronic paper).

Means for Generating an Electromagnetic Field The means for generating an electromagnetic field described in this application include all of the following conductor structures.

  -Conductors are distributed substantially in a plane.

  A net instantaneous current that is non-zero flows in a significant area of the plane. There is a region where the secondary devices given the correct posture efficiently combine and receive power (see FIG. 6).

  The conductor has the ability to generate an electromagnetic field in which the electromagnetic field lines fall within an angular range of 45 ° or less or are substantially parallel to a substantial area of the plane.

  FIG. 6 shows some possible examples of such a primary conductor. Although most structures are effectively coil windings, it can be seen that the same effect is achieved with a conductor plane that would typically be considered not a coil (see FIG. 6e). These figures are typical and not exhaustive. These conductors or coils are used in combination so that the secondary device efficiently couples at any rotational state on the charging area of the primary unit.

Magnetic material It is possible to use magnetic material in the primary unit to improve performance.

  The magnetic material is placed under one or more charging areas or the entire charging surface so that there is a low reluctance path under the conductor as the magnetic flux completes the path of the magnetic flux. Theoretically, an analogy can be made between a magnetic circuit and an electrical circuit. Voltage is similar to magnetomotive force (mmf), resistance is similar to reluctance, and current is similar to magnetic flux. From this point, it can be seen that for a given mmf, the flux flow increases if the path reluctance decreases. By providing the magnetic material below the charging area, the reluctance of the magnetic circuit is basically reduced. This significantly increases the magnetic flux linked by the secondary device and ultimately increases the power transmitted. FIG. 4d illustrates a sheet of magnetic material placed under the charging area and the resulting magnetic circuit.

  The magnetic material may be placed on the charging surface and / or charging area and under the secondary device to act as a flux guide. This flux guide performs the following two functions. First, the reluctance of the entire magnetic circuit is further reduced, allowing more magnetic flux to pass. Second, since a low reluctance path is obtained along the top surface of the charging region, the flux lines pass through these flux guides in preference to passing through the air. Therefore, the effect of confining the electromagnetic field in the vicinity of the charging surface of the primary unit rather than in the air can be obtained. The magnetic material used for the flux guide is chosen strategically or deliberately so that the magnetic core (if provided) of the secondary device has various magnetic properties. For example, a material with lower permeability and higher saturation is selected. High saturation means that the material can carry more magnetic flux, and low permeability means that when the secondary device is in the vicinity, a significant amount of magnetic flux will travel through the secondary device in preference to the flux guide. Represents the selection (see FIG. 8).

  -In the structure of the part of the electromagnetic field generating means of the primary unit, there are conductors that do not form part of the charging area as shown by component 745 in Figs. 6a and 6b. In such cases, it is desirable to use a magnetic material to shield the effects of these conductors.

  Examples of certain materials used include amorphous metals (metal glass alloys such as MetGlas®), mesh wires made from magnetic materials, steel, ferrite cores, mumetals and permalloy However, it is not limited to these examples.

Secondary devices Secondary devices come in a variety of shapes and forms. In general, to obtain excellent flux leakage, the central axis of the conductor (eg, coil winding) should not be substantially perpendicular to the charging area.

  The secondary device may be in the form of a flattened winding (see FIG. 7a). The internal magnetic core can be composed of a sheet of magnetic material such as amorphous metal. This geometric shape allows the secondary device to be incorporated into the back side of electronic devices such as mobile phones, personal digital assistants, and laptops without increasing the bulk of the device.

  -The secondary device may have a long cylindrical shape. A long cylindrical core can wrap the conductor (see FIG. 7b).

  The secondary device may be an object around which a magnetic material is wound. One example is a standard size (AA, AAA, C, D) or other size / shape (eg, for a particular application) where, for example, a magnetic material is wrapped around a cylinder and a winding is wrapped around the cylinder body Dedicated / custom) for rechargeable battery cells.

  The secondary device may be a combination of two or more of the above secondary devices. The above embodiments may be combined with conventional coils.

  The following non-exhaustive list describes some examples of objects that can be connected to a secondary device to receive power. The possibilities are not limited to the following examples.

Mobile communication device such as radio, mobile phone, or wireless device Portable communication device such as personal digital assistant, palmtop computer, or laptop computer Portable entertainment device such as music playback device, game Consoles or toys ・ Personal care products such as toothbrushes, shavers, hair curlers, hair rollers ・ Portable video devices such as video cameras or cameras ・ Containers for contents that require heating, such as coffee mugs, dishes・ Cooking pots, nail polish and cosmetic containers ・ Consumer devices such as flashlights, watches, blowers ・ Power tools such as cordless drills and screwdrivers ・ Wireless peripheral devices such as wireless computer mice, keyboards and headsets ・Time recording device, eg watch, wrist , Stopwatch, and alarm clock • Battery pack for insertion into any of the above devices • Standard size battery cells In the case of non-intelligent secondary devices such as battery cells, certain high-function charging control means It is necessary to measure the induced power to the cell and handle the situation where a large number of cells in the device take various charge states. Furthermore, it becomes more important that the primary unit can display a “charged” status, since the secondary cell or battery cannot be easily seen when located inside another electrical device.

  A possible system including an inductively rechargeable battery or cell and a primary unit is shown in FIG. In addition to the freedom to freely place the battery 920 at (X, Y) relative to the primary unit 910 and optionally rotate the battery at rZ, the battery continues to receive power and its rA It is also possible to rotate around the axis.

  When the user inserts the battery into the portable device, it is not easy to ensure that the battery has a predetermined axis rotation. Thus, embodiments of the present invention are very advantageous because they ensure that power can be received when the battery is in a random orientation about the rA axis.

  The battery or cell includes magnetic flux concentrating means that can be arranged in various ways:

1. As shown in FIG. 11a, the cell 930 is covered with a cylinder of magnetic flux concentrating material 931 and the magnetic flux concentrating material is covered with a coil 932 of wire.
a. The cylinder may be longer or shorter than the cell length.

2. As shown in FIG. 11 b, the cell 930 has a portion of the magnetic flux concentrating material 931 on the surface of the cell, and the magnetic flux concentrating material is covered with a coil 932 of wire.
a. A portion of the magnetic flux concentrating material follows the surface of the cell or is embedded in the cell.
b. The region of the magnetic flux concentrating material may be wider or narrower than the periphery of the cell, and may be longer or shorter than the length of the cell.

3. As shown in FIG. 11 c, the cell 930 stores a portion of the magnetic flux concentrating material 931 inside the cell, and the magnetic flux concentrating material is covered with a coil 932 of wire.
a. The portion is substantially flat, cylindrical, rod-shaped, or any other shape.
b. The width of the magnetic flux concentrating material may be wider or narrower than the cell diameter.
c. The length of the magnetic flux concentrating material may be longer or shorter than the length of the cell.

  In any of the above cases, the magnetic flux concentrating portion may be a functional part (for example, an outer lead electrode) of the battery housing, or may be the battery itself (for example, the inner electrode).

Problems associated with charging secondary cells (eg, AA type cells that can be recharged at their original location in the appliance) include the following:
・ The terminal voltage may be higher than normal.
-Series cells may behave abnormally, especially in situations where some cells are charged and others are not charged.
• It is necessary to supply enough power to move the device and charge the cell.
• If fast charging is performed by mistake, the cell will be destroyed.

  Therefore, it is advantageous to provide some kind of high-function charge control means in order to measure the inductive power to electric products and cells. Furthermore, it becomes more important that the primary unit can display a “charged” status, since the secondary cell or battery cannot be easily seen when located inside another electrical device.

  A cell or battery activated in this manner can be charged by placing the device on the primary unit while still attached to another device, or the cell or battery can be placed on the primary unit. By being left as it is, it is charged while being outside the device.

  A battery activated in this manner is arranged into a packet of cells like a typical device (eg, end-to-end or next to each other), and a set of cells in a single packet. Makes it possible to replace

  Alternatively, the secondary device may consist of a flat “adapter” with a thin electrode that fits over the battery in the device and is pushed down between the battery electrode and the device contact.

Rotating Electromagnetic Field In a coil as shown in FIGS. 6, 9a and 9b, the secondary device generally has a winding substantially parallel to the direction of the net current flow in the primary conductor as indicated by arrow 1. Combines efficiently only when placed in. For some applications,
・ The central axis of the secondary conductor is not perpendicular to the plane, and
As long as the condition that the secondary device is in close contact with the primary unit, a primary unit that efficiently transmits power to the secondary device is required regardless of the rotation of the secondary device.

  In order to make this possible, for example, two coils may be provided, one being placed on top of the other, or one being woven into the other, or associated with the other. Can generate a net current flow substantially perpendicular to the orientation of the first coil at any point in the active area of the primary unit. These two coils may be driven alternately so that each is actuated for a period of time. Another possibility is to drive the two coils in an orthogonal relationship so that a rotating magnetic dipole is generated in the plane. This is illustrated in FIG. This can also be combined with other coil structures.

Resonant circuit It is known in the art to drive a coil using a parallel or series resonant circuit. For example, in a series resonant circuit, the impedances of the coil and capacitor are equal and opposite in magnitude at resonance, so the total impedance of the circuit is minimized and the maximum current flows through the primary coil. Secondary devices are typically tuned to the operating frequency to maximize the induced voltage or current.

  Some systems, such as electric toothbrushes, typically provide a circuit that is detuned when no secondary device is present and tuned when the secondary device is in place. The magnetic material present in the secondary device shifts the self-inductance of the primary unit and resonates the circuit. In other systems, such as passive radio tags, there is no magnetic material present in the secondary device, so it does not affect the resonant frequency of the system. These tags are also typically small and are used far away from the primary unit so that even if magnetic material is present, the primary inductance is not significantly altered.

The situation is different in the proposed system.
A magnetic material that is highly permeable is present in the secondary device and is used very close to the primary unit.
• One or more secondary devices are carried very close to the primary unit at the same time.

This has the effect of significantly shifting the primary inductance and shifting to a different level depending on the number of secondary devices present on the pad. As the inductance of the primary unit is shifted, the capacitance required to resonate the circuit at a particular frequency also changes. There are three ways to keep the circuit in resonance:
• Use the control system to dynamically change the operating frequency.
Use the control system to dynamically change the capacity so that resonance is achieved at a predetermined frequency.
Use a low-Q system that maintains resonance over a range of inductances.

  The problem that arises from changing the operating frequency is that the secondary device is typically configured to resonate at a predetermined frequency. If the operating frequency changes, the secondary device will be detuned. In order to solve this problem, it is possible to change the capacity instead of the operating frequency. Secondary devices can be designed such that each additional device placed in the vicinity of the primary unit shifts the inductance to a quantized level and the appropriate capacitor is switched to resonate the circuit at a given frequency It is. Because of this resonant frequency shift, the number of devices on the charging surface can be detected and the primary unit can also detect when something is moved near the charging surface or when something is removed from the charging surface. It is possible to detect when. If a permeable object other than an effective secondary device is placed near the charging surface, it is unlikely to shift the system to a predetermined quantized level. In such situations, the system will automatically detune and reduce the current flowing into the coil.

  For a better understanding of the present invention and for describing the embodiments in which the present invention is implemented, reference will now be made, by way of example only, to the accompanying drawings.

  Referring initially to FIG. 1, two examples of prior art contactless power transfer systems are shown, both examples requiring precise alignment of the primary unit and the secondary device. This example is typically used with electric toothbrushes or cell phone chargers.

  FIG. 1 a shows a primary magnetic unit 100 and a secondary magnetic unit 200. On the primary side, the coil 110 is wound around a magnetic core 120 such as ferrite. Similarly, the secondary side includes a coil 210 wound around another magnetic core 220. During operation, alternating current flows into the primary coil 110 and generates a magnetic flux line 1. When the secondary magnetic unit 200 is placed in axial alignment with the primary magnetic unit 100, the magnetic flux 1 is coupled from the primary side to the secondary side and induces a voltage in the secondary coil 210.

  FIG. 1b represents a split transformer. The primary magnetic unit 300 includes a U-shaped core 320 around which a coil 310 is wound. When an alternating current flows into the primary coil 310, a changing magnetic flux line 1 is generated. The secondary magnetic unit 400 is configured by a second U-shaped core 420 around which another coil 410 is wound. When the secondary magnetic unit 400 is placed on the primary magnetic unit 300 so that the arms of the two U-shaped cores are in a straight line, the magnetic flux is effectively coupled to the core 420 on the secondary side, and the secondary coil 410 Induct a voltage into

  FIG. 2a is another example of a prior art inductive system typically used to power a radio frequency passive tag. The primary side typically comprises a coil 510 that covers a large area. When a large number of secondary devices 520 are within the area surrounded by the primary coil 510, a voltage is induced therein. The system does not require the secondary coil 520 to be accurately aligned with the primary coil 510. FIG. 2 b is a graph showing the magnitude of the magnetic flux intensity in the entire region surrounded by the primary coil 510 5 mm above the surface of the primary coil. This graph represents a non-uniform electromagnetic field that exhibits a minimum value 530 at the center of the primary coil 510.

  FIG. 3 represents another example of a prior art induction system in which an array of multiple coils is used. The primary magnetic unit 600 is constituted by an array of coils including coils 611, 612 and 613. The secondary magnetic unit 700 includes a coil 710. When the secondary magnetic unit 700 is in the vicinity of some of the coils of the primary magnetic unit 600, the coils 611, 612 are activated and other coils, such as the coil 613, are kept inactive. The activated coils 611 and 612 generate magnetic flux, and a part of the magnetic flux is coupled to the secondary magnetic unit 700.

  FIG. 4 shows one embodiment of the proposed embodiment. FIG. 4 a represents a primary coil 710 that has been wound or printed in such a way that there is a net instantaneous current in the active area 740. For example, if a direct current flows through the primary coil 710, all of the conductors in the active region 740 will flow in the same direction. A current flowing through the primary coil 710 generates a magnetic flux 1. The magnetic material layer 730 exists below the charging region to provide a return path for magnetic flux. FIG. 4b represents the same primary magnetic unit as the primary magnetic unit shown in FIG. 4a, but there are two secondary devices 800. When the secondary device 800 is placed in the correct position above the charging area 740 of the primary magnetic unit, the magnetic flux 1 will pass through the magnetic core of the secondary device 800 rather than through the air. The magnetic flux 1 through the secondary core will therefore induce a current in the secondary coil.

  FIG. 4c represents a partial outline of the magnetic flux density of the magnetic field generated by the conductor 711 in the charging area 740 of the primary magnetic unit. Underneath the conductor is a magnetic material layer 730 to provide a low resistance return path for the magnetic flux.

  FIG. 4d is a cross-sectional view of the charging area 740 of the primary magnetic unit. A possible path of the magnetic circuit is shown. The magnetic material 730 creates a low reluctance path for the circuit, and the magnetic core 820 of the secondary magnetic device 800 also creates a low reluctance path. This minimizes the distance that the magnetic flux has to travel through the air, thus minimizing leakage.

  FIG. 5 is a schematic diagram of one embodiment of the overall system of the proposed invention. In this embodiment, the primary unit includes a power source 760, a control unit 770, a detection unit 780, and an electromagnetic unit 700. The power supply 760 converts the mains power supply (or other power supply) into a DC power supply of an appropriate voltage for the system. The control unit 770 controls the drive unit 790 that drives the magnetic unit 700. In the present embodiment, the magnetic unit includes two independently driven components, coil 1 and coil 2, and the coil 1 and coil 2 are conductors in the charging region of the coil 1 and the charging region of the coil 2. It arrange | positions so that it may be orthogonal to an inner conductor. When the primary unit is activated, it causes a 90 degree phase shift between the alternating currents flowing in coil 1 and coil 2. This creates a magnetic dipole that rotates on the surface of the primary magnetic unit 700 so that the secondary device can receive power regardless of the direction of rotation (see FIG. 9). In the standby mode where there is no secondary device, the primary unit is detuned and the current flowing into the magnetic unit 700 is minimized. When the secondary device is placed on top of the charging area of the primary unit, the inductance of the primary magnetic unit 700 is changed. This resonates the primary circuit and maximizes the current. When two secondary devices are present on the primary unit, the inductance is further changed to another level and the primary circuit is detuned again. At this point, the control unit 770 uses feedback from the detection unit 780 to switch another capacitor to the circuit so that the circuit is tuned again and the current is maximized. In this embodiment, the secondary devices are of standard size, and up to six standard size devices can simultaneously receive power from the primary unit. Since the secondary device is a standard size, the inductance change caused by the change of the adjacent secondary device can cause a number of predetermined capacitances so that only a maximum of six capacitors are required to keep the system in resonance. Quantized to level.

  Figures 6a to 6l represent a wide variety of embodiments of the coil components of the primary magnetic unit. These embodiments are implemented as a coil component of the primary magnetic unit only if the rotation of the secondary device is important for power transfer. These embodiments may be implemented in combination and do not exclude embodiments not described herein. For example, the two coils illustrated in FIG. 6a may be placed at a 90 degree angle to each other to form a single magnetic unit. In FIGS. 6a to 6e, the charging region 740 is constituted by a series of conductors in which the net current generally flows in the same direction. In some structures, such as FIG. 6c, no power is transferred because there is no substantial leakage when the secondary device is placed directly above the center of the coil. In FIG. 6 d there is no substantial leakage when the secondary device is placed in the gap between the two charging areas 740.

  FIG. 6 f represents a particular coil structure for the primary unit adapted to generate an electromagnetic field that is substantially parallel to the surface of the primary unit within the charging region 740. Two primary windings 710, one on each side of the charging area 740, are formed around opposing arms of a substantially rectangular flux guide 750 made of magnetic material, with the primary winding 710 facing in the opposite direction. Generates an electromagnetic field. The flux guide 750 contains the electromagnetic field and creates a magnetic dipole in the charging area 740 in the direction of the arrow shown. When the secondary device is placed in the charging area 740 in a predetermined position, a low reluctance path is created and the magnetic flux passes through the secondary device, resulting in efficient coupling and power transfer. It should be understood that the flux guide 750 need not be continuous, but may actually be formed as two opposing unconnected horseshoe components.

  In FIG. 6, another possible coil structure of the primary unit is shown, which is adapted to generate electromagnetic field lines that are substantially parallel to the charging surface of the primary unit within the charging region 740. Yes. The primary winding 710 is wound around a magnetic core 750, which can be ferrite or other suitable material. Charging region 740 includes a series of conductors through which instantaneous net current generally flows in the same direction. The coil structure of FIG. 6g can support or define a charging region 740 on both the top and bottom surfaces, as shown in practice, depending on the configuration of the primary unit and the secondary device. One or both charging areas can be used.

  FIG. 6h represents a variation of the structure of FIG. 6g. The primary windings 710 are not evenly spaced as shown in FIG. 6g, but the windings 710 are unevenly spaced. The spacing and spacing variations are selected or designed to improve performance or field strength uniformity in the charging region 740.

  FIG. 6i shows that the two primary windings 710 as shown in FIG. 6g are reciprocal so that the direction of the electromagnetic field lines can be dynamically switched or rotated to another position around the plane of the charging surface. One Example arrange | positioned by the structure orthogonal to is shown.

  Figures 6j and 6k illustrate another two-coil structure of the primary unit that is not a simple geometric shape using conductors that are substantially parallel.

  In FIG. 6 j, line 710 shows one of the current propagation conductor sets in the plane of charging surface 600. The shape of the main conductor 710 is arbitrary and does not need to be a rectangular geometric shape. In practice, the conductor 710 may have a straight section and a curved section, and may intersect the conductor itself. One or more auxiliary conductors 719 are disposed along the main conductor 710 substantially parallel to the main conductor (at any given local point) (only two auxiliary conductors 719 are shown for clarity). ). The current flow in the auxiliary conductor 719 will be in the same direction as the flow in the main conductor 710. Auxiliary conductors 719 are connected in series or in parallel to form a single coil arrangement.

  In FIG. 6, a set of current carrying conductors 720 (only a portion of the conductors are shown for clarity) are aligned in the plane of the charging surface 600. The main conductor 710 is provided as shown in FIG. 6j, and the conductors 720 are disposed so as to be locally orthogonal to the main conductor 710, respectively. The conductors 720 may be connected in series or in parallel to form a single coil arrangement. If a first sine wave current is supplied to the conductor 710, a second sine wave current with a 90 ° phase shift relative to the first current is supplied to the coil 720, and then the two currents It will be appreciated that by changing the relative ratios and signs, the resulting field vector orientation at most points on the charging region 740 is rotated 360 °.

  FIG. 61 represents yet another alternative arrangement in which the magnetic core 750 is in the form of a disc with a hole in the center. The set of first current propagation conductors 710 is arranged in a spiral on the surface of the disk. The second set of conductors 720 is wound in a toroidal fashion radially outwardly through the center of the disk. These conductors are used when the secondary device is placed at any point inside the charging area 740 and rotated around an axis perpendicular to the charging area, for example using orthogonal sine wave currents. The device can be driven so that no zero is observed.

  7a and 7b are examples of the proposed secondary device. Winding 810 is wound around magnetic core 820. These two embodiments may be combined in a single secondary device, for example at a right angle, so that the secondary device can be efficiently coupled to the primary unit at every rotation. They may also be combined with a standard coil as shown at 520 in FIG. 2a to eliminate dead spots.

  FIG. 8 shows the effect of the magnetic flux guide 750 installed at the top of the charging area. The thickness of the material is exaggerated for clarity, but is actually on the order of millimeters. The flux guide 750 contains the magnetic flux instead of minimizing leakage and reducing the amount of magnetic flux coupled to the secondary device. In FIG. 8a, the primary magnetic unit is shown without the flux guide 750. The magnetic field tends to fringe in the air just above the charging area. As shown in FIGS. 8b-8f, with the flux guide 750, the flux is confined in the plane of the material and leakage is minimized. In FIG. 8e, the magnetic flux remains in the flux guide 750 when the secondary device 800 is not present at the top. In FIG. 8f, when there is a secondary device 800 with a very high permeability material such as a core, some of the magnetic flux will pass through the secondary device. The permeability of the flux guide 750 can be chosen to be higher than the permeability of a typical metal such as steel. When other materials, such as steel, that are not part of the secondary device 800 are placed on top, most of the magnetic flux remains in the flux guide 750 rather than traveling through the object. The magnetic flux guide 750 may not be a continuous layer of magnetic material, but has a small air gap inside to facilitate more magnetic flux to flow to the secondary device 800 when a secondary device is present.

  FIG. 9 represents an example of a primary unit in which two or more coils are used. FIG. 9 a shows a coil 710 with a charging region 740 where current flows parallel to the direction of arrow 2. FIG. 9b shows a similar coil arranged at 90 degrees with respect to the coil arrangement of FIG. 9a. When these two coils are placed on top of each other so that the charging area 740 overlaps, the charging area will appear as shown in FIG. 9c. Such an embodiment would allow the secondary device to rotate arbitrarily at the top of the primary unit and to couple efficiently.

  FIG. 10 shows an embodiment in which, for example, a secondary device that is a battery cell or a secondary device built in the battery cell has a shaft rotation. In this embodiment, the secondary device has the same degrees of freedom as described above (ie, translation (X, Y) and optionally rotation (rZ) perpendicular to the primary plane). The primary unit (910) is configured to be coupled to the primary magnetic flux at any shaft rotation (rA).

  FIG. 11 shows one arrangement in which a rechargeable battery 930 is covered with a cylinder of optional magnetic flux concentrating material 931 around which copper wire 932 is wound. This cylinder may be longer or shorter than the length of the battery.

  FIG. 11b shows another arrangement in which the magnetic flux concentrating material 931 covers only a portion of the surface of the battery 930 and the copper wire 932 is wrapped around the magnetic flux concentrating material 931 (not the battery). This material and wire are matched to the surface of the battery. These regions may be wider or narrower than the periphery of the battery, and may be longer or shorter than the length of the cell.

  FIG. 11 c shows another arrangement in which the magnetic flux concentrating material 931 is embedded in the battery 930 and the copper wire 932 is wrapped around the magnetic flux concentrating material 931. The material may be substantially flat, cylindrical, rod-shaped, or other shapes, the material width may be wider or narrower than the battery diameter, and the material length may be the length of the battery. It may be longer or shorter.

  In any of the cases shown in FIGS. 10 and 11, the magnetic flux concentrating material may be part of the battery housing (eg, outer zinc electrode) or the battery itself (eg, inner electrode).

  In either case shown in FIGS. 10 and 11, power may be stored in a smaller standard battery (eg, AAA size) housed in a large standard battery housing (eg, AAA size). .

  FIG. 12 shows one embodiment of a primary unit similar to the embodiment shown in FIG. 12a shows a coil that generates an electromagnetic field in the parallel direction in the drawing, FIG. 12b shows a coil that generates an electromagnetic field in the vertical direction in the drawing, and the two coils are mounted on substantially the same plane, It may be mounted on the other, or intertwined in some way. The wiring to each coil is indicated by reference numeral 940, and the charging area is represented by an arrow 941.

  FIG. 13 represents a simple embodiment of the drive unit (790 in FIG. 5). In this embodiment, there is no control unit. The PIC processor 960 generates two 23.8 kHz square waves that are 90 degrees out of phase with each other. These square waves are amplified by component 961 and driven by two coil components 962, which are identical to the magnetic unit shown in FIGS. 12a and 12b. This drive unit gives a rectangular wave, but the high resonance Q of the magnetic unit shapes this rectangular wave into a sinusoidal waveform.

  The preferred features of the invention are applicable to all aspects of the invention and are used in any conceivable combination.

  Throughout the description and claims, the words “comprise”, “contain” and variations of these words, eg, “ comprising ”and“ comprises ”means“ including but not limited to ”and includes components, integers, portions, additives, or steps not listed. Not intended to be excluded (and not excluded).

FIG. 2 shows the magnetic structure of a typical prior art contactless power transfer system that requires precise alignment of the primary unit and the secondary device. (A) showing the magnetic structure of another typical prior art non-contact power transmission system including a large coil in the primary unit, and a non-uniform electromagnetic field distribution inside the large coil at a distance of 5 mm from the face of the coil It is a figure which shows that taking the minimum value in the center (b). FIG. 2 is a diagram illustrating a multiple coil system in which each coil is independently driven so that a local electromagnetic field is generated. 1 is a diagram illustrating one embodiment of a proposed system that demonstrates a substantial difference from the prior art, with no secondary device provided. FIG. 2 shows an embodiment of the proposed system provided with two secondary devices. It is a figure which shows the cross section of the active area | region of a primary unit, and the outline of the magnetic flux density produced | generated by the conductor. FIG. 3 shows a magnetic circuit of a specific embodiment of the proposed invention. FIG. 2 is a schematic diagram of an embodiment of a primary unit and a secondary device. FIG. 5 shows an alternative implementation structure of the primary unit electromagnetic field generating means or components of the electromagnetic field generating means. FIG. 5 shows an alternative implementation structure of the primary unit electromagnetic field generating means or components of the electromagnetic field generating means. FIG. 5 shows an alternative implementation structure of the primary unit electromagnetic field generating means or components of the electromagnetic field generating means. FIG. 5 shows an alternative implementation structure of the primary unit electromagnetic field generating means or components of the electromagnetic field generating means. FIG. 5 shows an alternative implementation structure of the primary unit electromagnetic field generating means or components of the electromagnetic field generating means. FIG. 5 shows an alternative implementation structure of the primary unit electromagnetic field generating means or components of the electromagnetic field generating means. FIG. 5 shows an alternative implementation structure of the primary unit electromagnetic field generating means or components of the electromagnetic field generating means. FIG. 5 shows an alternative implementation structure of the primary unit electromagnetic field generating means or components of the electromagnetic field generating means. FIG. 5 shows an alternative implementation structure of the primary unit electromagnetic field generating means or components of the electromagnetic field generating means. FIG. 5 shows an alternative implementation structure of the primary unit electromagnetic field generating means or components of the electromagnetic field generating means. FIG. 5 shows an alternative implementation structure of the primary unit electromagnetic field generating means or components of the electromagnetic field generating means. FIG. 5 shows an alternative implementation structure of the primary unit electromagnetic field generating means or components of the electromagnetic field generating means. It is a figure which shows the feasible structure of the magnetic unit of a secondary apparatus. It is a figure which shows the feasible structure of the magnetic unit of a secondary apparatus. It is explanatory drawing which fringes in the air immediately above an active area | region when an electromagnetic field does not have a magnetic flux guide. It is explanatory drawing of the effect of the magnetic flux guide by which the current flow in the conductor in a specific Example was shown (For the sake of clarity, the thickness of the magnetic flux guide is exaggerated). It is explanatory drawing of the effect of the magnetic flux guide which shows that a magnetic flux is settled in the range of a magnetic flux guide when a magnetic material is arrange | positioned at the upper part of a charge area (The thickness of a magnetic flux guide is exaggerated for clarity.) . It is explanatory drawing of the effect of the magnetic flux guide in which the secondary apparatus exists in the upper part of a primary unit (For the sake of clarity, the thickness of the magnetic flux guide is exaggerated). It is explanatory drawing of the effect of the magnetic flux guide by which the cross section of the primary unit in case there is no secondary device was shown (for the sake of clarity, the thickness of the magnetic flux guide is exaggerated). It is an explanatory view of the effect of the magnetic flux guide, showing the cross section of the primary unit when the secondary device is at the top, and demonstrating the effect of using a secondary core with higher permeability than the magnetic flux guide (easy to understand The thickness of the magnetic flux guide is exaggerated). It is a figure showing the characteristic coil arrangement | positioning by which the net instantaneous current is shown by the direction of the arrow. FIG. 9b shows a coil arrangement similar to FIG. 9a except that it is rotated 90 degrees. FIG. 9b is a diagram representing the charging area of the primary unit when the coil of FIG. 9a is placed on top of FIG. 9b, and is a rotating magnetic dipole that is the effect when the coil of FIG. 9a is driven orthogonal to FIG. It is shown. It is a figure showing the case where a secondary apparatus has axial rotation. It is a figure which shows arrangement | positioning of the secondary apparatus rotated to an axial direction. Fig. 9b shows another example of a coil arrangement of the type shown in Fig. 9a. FIG. 9b shows another example of a coil arrangement of the type shown in FIG. 9b. FIG. 5 is a diagram illustrating a simple embodiment of a drive unit electronic circuit.

Claims (76)

A system for transmitting power without the need for direct electrical contact,
i) the system comprises a primary unit comprising a charging surface that is substantially layered and at least one means for generating an electromagnetic field;
The means includes two in a predetermined area so as to define at least one charging area of the charging surface that is at or substantially the same size as the predetermined area that is at or parallel to the charging surface. Dimensionally distributed, the charging area has a width and length on the charging surface,
The means includes a charging region in which the electromagnetic field generated by the means is measured parallel to the direction of the electromagnetic field lines when a predetermined current is supplied to the means and the primary unit is effectively electromagnetically shielded. The electromagnetic field lines distributed in a two-dimensional manner on the charging surface enter an angle range of 45 ° or less with respect to the charging surface in the vicinity of the charging surface when averaged over a quarter length. Configured to have
The means has a height measured substantially perpendicular to the charging area that is shorter than either the width or length of the charging area,
ii) the system comprises at least one secondary device comprising at least one electrical conductor;
When at least one secondary device is placed in or near the charging area of the primary unit, the electromagnetic field lines couple with at least one conductor of the at least one secondary device and induce a current flowing through the conductor. To
system.   The system of claim 1, wherein the means includes at least one electrical conductor distributed two-dimensionally in the charging area or substantially parallel to the charging area.   The said means comprises at least one electrical conductor wrapped around at least a portion of a magnetically permeable electrical conductor distributed two-dimensionally in the charging area or substantially parallel to the charging area. System.   4. A system according to any one of the preceding claims, wherein the means comprises a plurality of conductors configured to change in time the directional component of the electromagnetic field lines resolved into the charging area.   The system of claim 4, wherein the plurality of conductors are configured to switch a resolved directional component of the electromagnetic field lines between at least two different directions.   The system of claim 4, wherein the plurality of conductors are configured to move the resolved directional component of the electromagnetic field lines over an angle.   The system of claim 6, wherein the plurality of conductors are configured to rotate a resolved directional component of the electromagnetic field lines.   The system according to any one of claims 1 to 7, wherein the electromagnetic field lines above the predetermined charging area are substantially parallel to each other when projected to the charging area.   9. A system according to any one of the preceding claims, wherein the instantaneous net current flow in the predetermined one of the at least one means is substantially unidirectional when powered.   10. A system as claimed in any preceding claim, wherein the means does not protrude beyond the charging surface.   11. A system according to any one of the preceding claims, wherein at least one charging area is provided with a substrate of magnetic material.   The primary unit is configured to change at least one of the means for generating an electromagnetic field and a capacity of a circuit including at least one capacitor according to a detection result of the presence or absence of one or more secondary devices. 12. A system according to any one of the preceding claims, comprising a selectively operable capacitor.   13. A system according to any one of the preceding claims, wherein the at least one charging zone is provided with a magnetic flux guide having a permeability that is lower than the permeability of the core of at least one secondary device.   14. A system according to any one of the preceding claims, wherein the primary unit includes a power source.   15. A system according to any one of the preceding claims, wherein at least one conductor of the secondary device is wound around a core which serves to collect magnetic flux therein.   The system of claim 15, wherein the core is a magnetically permeable material.   The system of claim 16, wherein the core is an amorphous magnetic material.   The system of claim 17, wherein the core is a substantially non-annealed amorphous magnetic material.   19. A system according to any one of claims 15 to 18, wherein the core is formed as a flexible ribbon.   20. A system according to any one of the preceding claims, wherein the secondary device comprises an inductively rechargeable battery or cell.   21. The system of claim 20, wherein the inductively rechargeable battery or cell includes at least one conductor wrapped around the magnetic flux concentrating means.   22. A system according to any one of the preceding claims, wherein at least one of the at least one means is configured to generate an electromagnetic field over two or more charging regions.   22. A system according to any one of the preceding claims, wherein a plurality of said means are configured to generate an electromagnetic field over a single charging area.   24. A system according to any one of the preceding claims, wherein the means has a height shorter than half the length or half the width of the charging area.   25. A system according to any one of the preceding claims, wherein the means has a height shorter than 1/5 of the length of the charging area or 1/5 of the width. A primary unit that transmits power without the need for direct electrical contact,
The primary unit includes a charging surface that is substantially layered and at least one means for generating an electromagnetic field;
The means includes two in a predetermined area so as to define at least one charging area of the charging surface that is at or substantially the same size as the predetermined area that is at or parallel to the charging surface. Dimensionally distributed, the charging area has a width and length on the charging surface,
The means is a charging region in which the electromagnetic field generated by the means is measured in parallel with the direction of the electromagnetic field lines when a predetermined current is supplied to the means and the primary unit is effectively electromagnetically shielded. Electromagnetic field lines distributed in a two-dimensional manner on the charging surface within an angle range of 45 ° or less with respect to the charging surface in the vicinity of the charging surface when averaged over a quarter length of Is configured to have
The means has a height measured substantially perpendicular to the charging area that is shorter than either the width or length of the charging area,
Primary unit.   27. A primary unit according to claim 26, wherein the means comprise at least one electrical conductor distributed two-dimensionally in the charging area or substantially parallel to the charging area.   27. The means includes at least one electrical conductor wrapped around at least a portion of a magnetically permeable electrical conductor distributed two-dimensionally in the charging area or substantially parallel to the charging area. Primary unit.   29. A primary unit as claimed in any one of claims 26 to 28, wherein the means comprises a plurality of conductors configured to temporally change the directional component of the electromagnetic field lines resolved into the charging area.   30. The primary step of claim 29, wherein the plurality of conductors are configured to switch the resolved directional component of the electromagnetic field lines between at least two different directions.   30. The primary unit of claim 29, wherein the plurality of conductors are configured to move the resolved directional component of the electromagnetic field lines over an angle.   32. The primary unit of claim 31, wherein the plurality of conductors are configured to rotate a decomposed directional component of the electromagnetic field lines.   33. A primary unit according to any one of claims 26 to 32, wherein the electromagnetic field lines above the predetermined charging area are substantially parallel to each other when projected onto the charging area.   34. A primary unit according to any one of claims 26 to 33, wherein the instantaneous net current flow in the predetermined one of the at least one means when energized is substantially unidirectional.   35. A primary unit as claimed in any one of claims 26 to 34, wherein the means do not protrude beyond the charging surface.   36. The primary unit according to any one of claims 26 to 35, wherein at least one charging region is provided with a base material of magnetic material.   At least one selectively operating, wherein the capacity of a circuit including at least one means for generating an electromagnetic field and at least one capacitor is changed according to the detection result of the presence or absence of one or more secondary devices. 37. A primary unit according to any one of claims 26 to 36, comprising a possible capacitor.   38. A primary unit according to any one of claims 26 to 37, wherein the primary unit includes a power source.   The primary unit according to any one of claims 26 to 38, wherein the at least one charging region is provided with a magnetic flux guide having a permeability lower than that of any core provided in the at least one secondary device. .   40. A primary unit according to any one of claims 26 to 39, wherein at least one of the at least one means is configured to generate an electromagnetic field on two or more charging regions.   40. A primary unit according to any one of claims 26 to 39, wherein a plurality of said means are configured to generate an electromagnetic field on a single charging area.   42. A primary unit as claimed in any one of claims 26 to 41, wherein the means has a height shorter than half the length or half of the width of the charging area.   43. A primary unit according to any one of claims 26 to 42, wherein the means has a height shorter than 1/5 of the length of the charging area or 1/5 of the width. A method of non-conductively transmitting power from a primary unit to a secondary device, comprising:
The primary unit includes a charging surface that is substantially layered and at least one means for generating an electromagnetic field;
The means includes two in a predetermined area so as to define at least one charging area of the charging surface that is at or substantially the same size as the predetermined area that is at or parallel to the charging surface. Dimensionally distributed, the charging area has a width and length on the charging surface,
The means has a height measured substantially perpendicular to the charging area that is shorter than either the width or length of the charging area,
The secondary device has at least one electrical conductor;
i) an electromagnetic field generated by the means when supplied with a predetermined current and measured when the primary unit is effectively electromagnetically shielded is a charge region measured parallel to the direction of the electromagnetic field lines; Enter an angular range of 45 ° or less with respect to the charging surface in the vicinity of the charging surface when averaged along the quarter length, and at least one when averaged over the charging region Having electromagnetic field lines distributed two-dimensionally on the charging area;
ii) the electromagnetic field couples with the conductor of the secondary device when the secondary device is placed in or near the charging area;
Method.   45. The method of claim 44, wherein the means comprises at least one electrical conductor distributed two-dimensionally in the charging area or substantially parallel to the charging area.   45. The means includes at least one electrical conductor wrapped around at least a portion of a magnetically permeable electrical conductor distributed two-dimensionally in the charging area or substantially parallel to the charging area. the method of.   47. A method according to any one of claims 44 to 46, wherein the directivity component of the electromagnetic field lines resolved into the charging area is varied over time.   48. The method of claim 47, wherein the resolved directional component of the electromagnetic field lines is switched between at least two different directions.   48. The method of claim 47, wherein the resolved directional component of the electromagnetic field lines is moved over an angle.   50. The method of claim 49, wherein the resolved directional component of the electromagnetic field lines is rotated.   51. A method according to any one of claims 44 to 50, wherein the electromagnetic field lines above the predetermined charging area are substantially parallel to each other when projected to the charging area.   52. A method according to any one of claims 44 to 51, wherein the instantaneous net current flow in the predetermined one of the at least one means when energized is substantially unidirectional.   53. A method according to any one of claims 44 to 52, wherein at least one charging zone is provided with a substrate of magnetic material, which completes the magnetic circuit.   The primary unit is at least one selectively switched so that the capacity of the circuit including at least one means for generating an electromagnetic field and at least one capacitor can be changed according to the detection result of the presence or absence of one or more secondary devices. 54. A method according to any one of claims 44 to 53, comprising a operable capacitor.   The charging surface is provided with a magnetic flux guide having a permeability lower than that of any core provided in at least one secondary device, reliably within at least one charging area. Any one of the methods. A secondary device for use with the system, primary unit or method of any one of claims 1 to 55, comprising:
Including at least one electrical conductor and having a shape factor that is substantially layered;
Secondary device.   57. The secondary device of claim 56, wherein the at least one electrical conductor is wrapped around a core that serves to collect magnetic flux therein.   58. The secondary device of claim 57, wherein the core is a magnetically permeable material.   59. The secondary device of claim 58, wherein the core is an amorphous magnetic material.   60. The secondary device of claim 59, wherein the core is an amorphous magnetic material that is substantially unannealed.   61. A secondary device according to any one of claims 57 to 60, wherein the core is formed as a flexible ribbon.   62. The secondary device according to any one of claims 56 to 61, wherein the secondary device comprises an inductively rechargeable battery or cell.   63. The secondary device according to any one of claims 57 to 62, comprising a core having a thickness of 2 mm or less.   64. The secondary device of claim 63, having a core with a thickness of 1 mm or less.   65. The secondary device according to any one of claims 56 to 64, wherein the secondary device has a main shaft, and is arbitrarily rotated around the main shaft to couple with an electromagnetic wave when located in the charging region or the vicinity of the charging region. Secondary device.   66. A secondary device according to claim 65, dependent on claim 62, wherein the core is at least partially covered around a central portion of the battery or cell.   The primary unit includes a pair of conductors having adjacent coplanar windings, the adjacent coplanar windings extending substantially parallel to the plane of the winding and substantially perpendicular to the parallel sections. 26. A system according to any one of the preceding claims, having linear sections substantially parallel to each other arranged to produce a broadening substantially uniform electromagnetic field.   68. The system of claim 67, wherein the winding comprises a series of turns having a straight section that is substantially helical and is substantially parallel. The primary unit includes a pair of first and second conductors superimposed in a substantially parallel plane, and the substantially parallel straight section of the first pair is a substantially parallel straight line of the second pair. Arranged approximately perpendicular to the section,
A drive circuit arranged to drive the pair of first and second conductors to generate a composite electromagnetic field that rotates in a plane that is substantially parallel to the plane of the winding;
69. A system according to claim 67 or 68.   Including a pair of conductors having adjacent coplanar windings, the adjacent coplanar windings extending substantially parallel to the plane of the windings and extending substantially perpendicular to the parallel sections. 44. A primary unit according to any one of claims 26 to 43, having linear sections substantially parallel to each other arranged to generate a uniform electromagnetic field.   72. The primary unit of claim 70, wherein the winding comprises a series of turns having a straight section that is substantially spiral and is substantially parallel. A pair of first and second conductors superimposed in a substantially parallel plane, the substantially parallel straight section of the first pair relative to the substantially parallel straight section of the second pair; Arranged almost at right angles,
A drive circuit arranged to drive the pair of first and second conductors to generate a composite electromagnetic field that rotates in a plane that is substantially parallel to the plane of the winding;
72. A primary unit according to claim 70 or 71.   A system for transmitting power substantially as herein described with reference to FIGS. 4 to 13 of the accompanying drawings.   A primary unit for transmitting power substantially as described in the specification with reference to FIGS. 4 to 13 of the accompanying drawings.   14. A method of transmitting power substantially as described herein with reference to FIGS. 4 to 13 of the accompanying drawings.   A secondary device for receiving power substantially as described herein with reference to Figures 4-13 of the accompanying drawings.

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