JP5184986B2 - ANTENNA DEVICE AND RADIO DEVICE - Google Patents

Description

  The present invention relates to an antenna device and a wireless device, and more particularly to an antenna device including a coil-shaped element and a wireless device using the antenna device.

  Wireless non-contact individual identification (Radio Frequency Identification, hereinafter abbreviated as RFID) technology is widely used in railway automatic ticket gates, company / office management, and various electronic money. . In the RFID, information is exchanged through wireless communication between a device called a reader / writer and an information medium called a card or a tag.

  By placing the antenna (which may be referred to as a loop antenna or a loop coil antenna) made of a coiled element built in the reader / writer and the antenna made of the coiled element built in the card so that they can communicate with each other, the reader The writer can write information to and read information from the card. A part of the mobile phone is also equipped with a function corresponding to such RFID. Initially, card functions are installed in mobile phones, and recently, reader / writer functions are also installed.

  Conventionally, attachment of an antenna formed of a coil-shaped element to a mobile phone has been performed using a method such as sticking to a guide wall in a casing with an adhesive tape, engagement with an engaging claw, and fixing with an adhesive. In addition, since it is difficult to keep the loop shape fixed in these methods, it is not easy to assemble, and in order to cope with the problem that an error in the mounting position and a variation in performance due to this are likely to occur, the coil-shaped element is mounted. There is also known a technique of disposing on the inner surface of the body and fixing with a frame-shaped member from above (see, for example, Patent Document 1).

According to Patent Document 1, for example, a rectangular frame-shaped loop coil antenna (coiled element) is arranged along the side surface of the inner wall of the housing, and is fixed by the same rectangular frame-shaped antenna fixing member from above. In addition, it is described that variation in shape after the incorporation of the coil-like element can be suppressed over the entire circumference.
JP 2008-11275 A (page 4, FIG. 8)

  In the conventional technique disclosed in Patent Document 1 described above, for example, a coil-shaped element is disposed along a groove (guide) formed on the inner surface of the housing, and a fixing member formed in accordance with the shape of the groove is provided from above. It fits in. The shape of the housing having the groove on the inner surface and the fixing member may be complicated depending on other component mounting conditions and housing design. In addition, the work of disposing the coil-like element and fitting the fixing member may become complicated, and the production efficiency may be reduced.

  The present invention has been made to solve the above-described problems, and facilitates attachment of a coiled element constituting an antenna device to a radio device casing, and extends the structure of the antenna device to other purposes. The purpose is to make it available.

  In order to achieve the above object, an antenna device of the present invention includes a coiled element formed by winding a conductive wire and a conductive portion, and covers the periphery of the conductive wire of the coiled element. And a covering member attached in such a manner.

  The wireless device according to the present invention includes a casing, and a coiled element formed by winding a conductive wire, the periphery of which is covered with a covering member formed with a conductive portion. And an antenna device disposed inside the body.

  According to the present invention, the loop shape is fixed by covering the conductive wire of the coil-shaped element with the covering member having a conductive portion (for example, by inserting the conductive wire through a metal tube) to constitute the antenna device. Therefore, the conductive part of the covering member can be expanded and used for other purposes.

  Embodiments of the present invention will be described below with reference to the drawings. In addition, when referring to the following figures, up, down, left, right, horizontal, vertical (vertical) means up, down, left, right, horizontal, vertical (vertical) on the paper on which the figure is represented, unless otherwise specified. . Moreover, the same code | symbol shall represent the same structure between each figure.

  Embodiment 1 of the present invention will be described below with reference to FIGS. FIG. 1 is a perspective view illustrating an appearance of a wireless device 1 according to the first embodiment of the invention. For example, the wireless device 1 is configured by connecting two housings in a foldable manner, and FIG. 1 shows a folded state. Of the two housings of the wireless device 1, the one that hits the lower side in FIG.

  FIG. 2 is a simplified view of the lower half of the members constituting the housing 11 (in the following description, this portion is referred to as the housing 11). As shown in FIG. 2, the housing 11 can be represented, for example, by imitating a vertically long shallow container. The upper side and the lower side of the bottom surface of the housing 11 correspond to the inside and the outside of the wireless device 1, respectively.

  A rectangular component 12 having a certain thickness is provided on the bottom surface of the housing 11. An antenna device 13 is provided so as to surround the component 12. As will be described later, the antenna device 13 includes a coil-like element wound with a conductive wire inserted into a metal tube-like member and a power feeding portion 14. Note that the component 12 is not limited to a type, and may be composed of a plurality of components or may include a part of the housing 11.

  The configuration of the antenna device 13 will be described in more detail with reference to FIGS. FIG. 3 is a diagram illustrating the shape and configuration of the antenna device 13 as seen in a plan view from a position corresponding to the upper side of FIG. The antenna device 13 includes a feeding portion 14, a coil-shaped element 15 configured to form a loop shape by winding a conductive wire three times, and a metal tube-shaped member 16 (contour and hatching represented by a dotted line) It is represented by.)

  The power supply unit 14 is configured, for example, by providing a pair of power supply terminals 14a and 14b and a required conductor pattern on a small substrate, and is connected to the conductive wire of the coiled element 15 via a connector, for example. The power supply terminals 14a and 14b are connected to a card radio circuit of, for example, a non-contact type individual identification (RFID) system (a use frequency is a 13 megahertz (MHz) band) (not shown).

  The conductor pattern provided on the substrate of the power feeding unit 14 and the conductive wires constituting the coiled element 15 are sequentially connected in series to form a three-turn coil as a whole from the power feeding terminal 14a to the power feeding terminal 14b. . The conductive wire of the coil-shaped element 15 is inserted through the metal tubular member 16.

  FIG. 4 is a cross-sectional view in a cross section perpendicular to the longitudinal direction of the coil-shaped element 15 and the tubular member 16. The three conductive wires 15a constituting the coil-shaped element 15 are each covered with an insulating coating 15b, and three are integrally covered with a sheath 15c made of an insulating material. The tubular member 16 has a shape in which the outside of the sheath 15 c is covered with metal, and the metal portion extends over the entire length of the tubular member 16.

  Since the coil-like element 15 is inserted through the metal tubular member 16, the loop shape can be kept fixed. Therefore, when the coil-shaped member 15 is attached to the housing 11 so as to surround the component 12 as shown in FIG. 2, there is a possibility that the loop shape may collapse and the attachment becomes difficult, and further, a fixing member needs to be attached and fixed. There is no sex.

  For example, as described above, the coil-shaped element 15 is excited at a frequency of 13 MHz as a card antenna of an RFID system. On the other hand, if the wireless device 1 is, for example, a mobile phone, the total length of the tubular member 16 is at most several tens of centimeters (cm) in view of the general size of the housing 11 and has a frequency of 13 MHz band. The value is two orders of magnitude smaller than the wavelength. Even if such a small-sized metal is close to the excitation wavelength, the electrical characteristics of the coiled element 15 are not affected, and the influence on the operation of the RFID system as a card antenna can be ignored. .

  Even if the tube-shaped member 16 is not made of metal, it is sufficient if it has a conductive portion formed by, for example, plating a metal on a resin tube. The conductive portion does not necessarily extend over the entire length of the tubular member 16.

  Instead of the tubular member 16, a covering member formed in a planar shape from a material having a conductive portion may be used, and the covering member may be attached so as to cover the periphery of the coiled element 15. FIG. 5 is a diagram showing such a modification. Also according to the modified example as shown in FIG. 5, since the conductive portion of the covering member has a certain rigidity, the loop shape of the coiled element 15 can be kept fixed.

  According to the first embodiment of the present invention, it is possible to easily attach the coiled element to the wireless device casing by inserting the conductive wire of the coiled element through the metal tube and keeping the loop shape fixed. Can do.

  Hereinafter, Embodiment 2 of the present invention will be described with reference to FIG. FIG. 6 is a diagram illustrating a configuration and connection of main parts of the wireless device 2 according to the second embodiment of the present invention. Similar to the wireless device 1 of the first embodiment, the wireless device 2 includes an antenna device 13 that includes a coil-shaped member 15 and a metal tube-shaped member 16. In order to make the drawing easier to see, the coil-like member 15 is shown in a single-turn form even if it is configured by winding the conductive wire a plurality of times.

  The wireless device 2 includes a wireless circuit (1) 21 and a wireless circuit (2) 22. The radio circuit (1) 21 is, for example, a card radio circuit for an RFID system. The radio circuit (2) 22 is, for example, a radio circuit for a reader / writer in an RFID system. As shown in FIG. 6, the coil-shaped member 15 is connected to the radio circuit (1) 21 at both ends. The tubular member 16 is connected to the radio circuit (2) 22 at both ends.

  The wireless device 2 may include a control circuit (not shown). When the wireless device 2 is used as an RFID system card, the control circuit operates the wireless circuit (1) 21 and switches when the wireless device 2 is used as an RFID system reader / writer. 2) 22 can be operated.

  Then, when the wireless device 2 is used as an RFID system card, the coiled element 15 operates as an antenna for the card, and when the wireless device 2 is used as an RFID system reader / writer, the tubular member 16 is a reader / writer. Operates as an antenna. That is, the antenna device 13 can be switched and used as an antenna of two different systems.

  In the above case, by setting the natural resonance frequency of the tubular member 16 to a value higher than the standard frequency of the RFID system, resonance on the external card side due to mutual coupling when facing and close to the external card Stable communication can be performed by suppressing frequency shift (frequency split phenomenon).

  The radio circuit (1) 21 is not limited to the card radio circuit of the RFID system, and may be any system radio circuit that can use the coiled element 15 as an antenna. The radio circuit (2) 22 is not limited to the RFID circuit reader / writer radio circuit, and may be any system radio circuit that can use the tubular member 16 as an antenna. The radio circuit (1) 21 and the radio circuit (2) 22 may be used simultaneously instead of being switched.

  Similar to the first embodiment, a covering member formed in a planar shape from a material having a conductive portion may be used instead of the tubular member 16.

  According to the second embodiment of the present invention, the coil-like element and the tubular member are connected to separate systems, respectively, so that they can be used as antennas of two different systems.

  Hereinafter, Embodiment 3 of the present invention will be described with reference to FIG. FIG. 7 is a diagram illustrating a configuration and connection of main parts of the wireless device 3 according to the third embodiment of the present invention. The wireless device 3 includes an antenna device 33 configured to include a coiled member 15 similar to the wireless device 1 of the first embodiment and a tube-shaped member 36 through which the coiled member 15 is inserted.

  The tubular member 36 has a conductive portion 36a, a nonconductive portion 36b, and a conductive portion 36c. The conductive portions 36a and 36c can be formed, for example, by performing metal plating on a resin tube. In that case, the non-conductive portion 36b corresponds to a portion left without plating the resin tube.

  The conductive portions 36a and 36c are metal tubes, and the non-conductive portion 36b is a resin tube. The tube-shaped member 36 may be formed by joining them in order. Regardless of the forming method, the conductive portions 36a and 36c are discontinuous and non-conductive with each other.

  The wireless device 3 includes a wireless circuit (1) 31, a wireless circuit (2) 32, and a wireless circuit (3) 33. The radio circuit (1) 31 is, for example, an RFID system card or a reader / writer radio circuit. The radio circuit (2) 22 is, for example, a radio circuit for a receiver of the global positioning system (GPS). The radio circuit (3) 32 is, for example, a radio circuit for a transceiver of a mobile phone.

  As shown in FIG. 7, the coil-shaped member 15 is connected to the radio circuit (1) 31 at both ends. The conductive portion 36a of the tubular member 36 is connected to the wireless circuit (2) 32 at one end. The conductive portion 36c of the tubular member 36 is connected to the wireless circuit (3) 33 at one end.

  According to the above-described configuration and connection of the wireless device 3, the antenna device 33 can simultaneously operate as an antenna for three systems of a mobile phone, GPS, and RFID (card or reader / writer).

  The wireless circuit (1) 31 is not limited to a wireless circuit for an RFID system, and may be a wireless circuit for any system that can use the coiled element 15 as an antenna. The wireless circuit (2) 32 is not limited to a GPS receiver wireless circuit, and may be a wireless circuit for any system that can use the conductive portion 36a of the tubular member 36 as an antenna. .

  Further, the radio circuit (3) 33 is not limited to a radio circuit for a transceiver of a mobile phone, and may be any radio circuit for any system that can use the conductive portion 36c of the tubular member 36 as an antenna. Good. Similarly to the second embodiment, the wireless device 3 may include a control circuit (not shown) and perform some switching between the three systems.

  According to the third embodiment of the present invention, the two discontinuous conductive portions of the tubular member and the coiled element are connected to separate systems, respectively, so that they can be used as antennas for three different systems. . Similar to the first embodiment, a covering member formed in a planar shape from a material having a conductive portion may be used instead of the tubular member 36.

  In the description of each of the above embodiments, the shape, arrangement, positional relationship of each component, the number of discontinuous conductive portions of the tubular member, and the number of wireless circuits for different systems are merely examples. Various modifications are possible without departing from the scope of the invention.

1 is a perspective view illustrating an appearance of a wireless device according to Embodiment 1 of the present invention. FIG. 3 is a diagram schematically illustrating a lower half of a member constituting a housing of the wireless device according to the first embodiment. FIG. 3 is a diagram illustrating the shape and configuration of the antenna device according to the first embodiment when viewed from the top in FIG. Sectional drawing in a cross section perpendicular | vertical to the direction of the longitudinal direction of the coil-shaped element which concerns on Example 1, and a tubular member. FIG. 6 is a diagram illustrating a modification of the first embodiment. The figure showing the structure and connection of the principal part of the radio | wireless apparatus which concern on Example 2 of this invention. The figure showing the structure and connection of the principal part of the radio | wireless apparatus which concern on Example 3 of this invention.

Explanation of symbols

1, 2 and 3 Wireless device 11 Housing 12 Parts 13 and 33 Antenna device 14 Feeding portions 14a and 14b Feeding terminal 15 Coiled element 15a Conductive wire 15b Insulating coating 15c Sheath 16 and 36 Tube-shaped members 21 and 31 Radio circuit ( 1)
22, 32 Radio circuit (2)
33 Radio circuit (3)
36a, 36c Conductive portion 36b Non-conductive portion

Claims (11)

A coiled element formed by winding a conductive wire;
In planar, has a portion of conductive, surrounds the periphery of the conductive wire, and a covering member made mounted for the covering to be opposed spaced edges portions along said conductive wire An antenna device comprising:   The antenna device according to claim 1, wherein a conductive wire of the coiled element is inserted through the covering member.   The antenna device according to claim 1, wherein the conductive portion extends over the entire length of the covering member.   3. The antenna device according to claim 1, wherein the conductive portion is divided into at least a first conductive portion and a second conductive portion that are discontinuous with each other. A housing,
The coiled element conductive wire is wound, in flat, the covering member to have a portion of the conductive, so that the sides face each other and spaced apart along the ambient to the enclosure the conductive wire We are covered in and wireless device being characterized in that an antenna device which is disposed inside the housing.   The radio apparatus according to claim 5, wherein a conductive wire of the coiled element is inserted through the covering member.   The wireless device according to claim 5, wherein the conductive portion extends over the entire length of the covering member.   The wireless device according to claim 5, wherein the conductive portion is divided into at least a first conductive portion and a second conductive portion that are discontinuous with each other. A radio circuit for the first system and a radio circuit for the second system;
6. The coil-like element is connected to a radio circuit for the first system, and the conductive portion is connected to a radio circuit for the second system. 6. The wireless device according to 6.   The coiled element is connected to the first system radio circuit for excitation, and the conductive portion is connected to the second system radio circuit for excitation. The radio apparatus according to claim 5 or 6, further comprising switching means capable of switching between states.   A wireless circuit for the first system, a wireless circuit for the second system, and a wireless circuit for the third system, wherein the conductive portion is at least a first conductive portion that is discontinuous with each other; The coiled element is divided into a second conductive part, the coiled element is in the first system radio circuit, and the first conductive part is in the second system radio circuit, 7. The radio apparatus according to claim 5, wherein the second conductive portion is connected to a radio circuit for the third system.

Images