JPS60113646A - Disc type brushless motor with one position detector - Google Patents

Abstract

PURPOSE:To self-start a magnet rotor by providing cocking generating means at the prescribed position to an armature coil. CONSTITUTION:A square case 9 for a disc brushless fan motor has a central through hole 10, and a projection 9a is provided on the inner periphery of the hole 10. A fan motor FM is supported by bearings 11, 12. A stator armarure 1 has an armature coil 4 provided on a stator armature. A cup unit 20 with a fan is disposed on the armature 1. A magnetic yoke 27 and a field magnet 2 are secured to the unit 20. A screw 15 as cocking generating means is provided at the position of the prescribed width from the conductor unit which contributes to a torque generated from an armature coil 4 opposed to the rotating direction of the magnet rotor 2.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a disk-type brushless motor having one position sensing element and which is energized in one phase.

BACKGROUND ART Conventionally, as various devices have appeared, there has been a demand for brushless morphs, particularly disk-type brushless motors, that are suitable for the devices. This disc-type brushless motor can also be used as a disc-type brushless fan motor used in office machines, etc.
Depending on the device to which it is applied, it is required to be extremely inexpensive, small, and extremely flat.

Here, the one that most satisfies this condition is a one-phase (energized) disc-type brushless motor that has one armature coil and one position detection element. Although it is possible to rotate the child over a predetermined range, it is not possible to rotate it continuously, making it difficult to construct a disc-type brushless motor. Furthermore, even if one armature coil can rotate a brushless motor with one position detection element, a strong rotational force cannot be obtained with only one armature coil. To do this, the armature coil must be
It needs to be used as a side plate.

Conventionally, a disk-type brushless motor having two armature coils as a stator armature requires two position detection elements. Here, as a position sensing element.

Magnetoelectric conversion elements such as Hall elements and Hall ICs are often used, but these position sensing elements are expensive, so
If possible, it is preferable to use only one since it is possible to mass-produce inexpensive and small disc-type brushless motors. However, when there is only one position sensing element, this element detects the boundary between the north and south poles of the field magnet, that is, the dead e point, when the motor is started, just as when there is only one armature coil. It has the disadvantage that it cannot start automatically if it is running. To this end, the applicant has previously devised an idea aimed at obtaining a two-coil disc-type brushless motor that can be self-started even with a single position sensing element, and is efficient and inexpensive. Gansho 58-5G
No. 659 and No. 58-28958. According to this invention, coking is generated at the most suitable position, and even with just one position sensing element, the magnetic rotor can be moved from the dead ψ point to a state where it can be started at any time when stopped or when started. This has the effect of making it possible to obtain a disc-type brushless motor that is inexpensive and useful.

As another example, we have provided one in which one armature coil having the same effect as two L article 1 Ikuko coils is used to achieve the same purpose. The present invention will be described in detail regarding such a configuration, but the present invention provides other positions where coking should occur in the above-mentioned example. That is, in the present invention, in the direction of rotation of the magnet rotor, from the conductor portion that contributes to the generated torque of the armature coil, the distance from the conductor part contributing to the torque generated by the armature coil is approximately 100 nm. Width n: A positive integer of 1 or more is characterized in that coking occurs at the front position.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 shows one position sensing element and two position sensing elements as the first embodiment.
+il, 4(il, 1-phase disc type brushless motor, code 8 is a space part, this space part 8 can be used to incorporate electric parts for the current-carrying side ζ-circuit, simplifying the mass production process. This makes it possible to obtain a disk-type brushless motor or a disk-type brushless fan motor FM that is inexpensive and has good performance.For a cup-shaped disk-type brushless fan motor that is flat in the axial direction, for example, made of a magnetic material. The square case 9 (see Figure 2) has a central through hole 1.
0, and the inner peripheral portion of the through hole 10 has a protrusion 9a extending in the L direction. Bearings;
6 is rotatably supported. Lower gIS of rotating shaft 16
An E-ring 14 for preventing removal is provided. Reference numeral 21 is a concave part of the case 9 (see 21.-4), 22 is an air hole provided in the 4th part of the case 9, 23 is a stay, 24-1 and 24-2 are a positive power cord and a negative power source, respectively. It is a code. Reference numeral 9b denotes a support provided on the cup body 9, and the printed circuit board 6 is fixed to the top of the support 9b by screws 15 made of magnetic material. Two armature coils 4 are arranged 180 degrees symmetrically on the printed circuit board 6 as shown in FIG.
The stator armature 1 is formed by the armature coils 4. The stator "t4-M element 1 faces a fan-equipped cup body 20 made of plastic that is flat in the axial direction as shown in FIG. A fan is integrally formed with the cup body.

A boss portion 26 is integrally formed approximately at the center of the inner surface of the cup body 20, and the L end portion of the rotary shaft 16 is fixed to the boss portion 26 so as to rotate integrally therewith. An annular magnetic yoke 2 is provided on the inner surface = ts of the cup body 20.
7 is fixed.

The lower surface of the rotor yoke 27 has N, S as shown in FIG.
An annular four-pole field (a magnet (magnet rotor) 2 having alternating magnetic poles is fixedly installed, and the stator armature 1
They are facing each other. On the surface of the printed circuit board B facing the field magnet 2, as described above and shown in FIG. Two armature coils 4-1 and 4-2, which are wound approximately equally, are arranged 180 degrees symmetrically so as not to overlap each other. h of printed circuit board 6
As shown in Fig. 1, electrical components 7 (transistors), 6 (resistors), etc. for the energization control circuit are arranged on the lower surface of O' outside the occupied position of the child coil 4-1, 4-2. . Incidentally, since the conductor portion 4b in the circumferential direction of the armature coil 4-1, 4-2 does not contribute to the generated torque, even if a field magnet 2 whose radius is small by the radius of this conductor Li1-4b is used. It's going to be a good thing. In addition, since the field magnet 2 used a 4-pole type, the armature coil and loops 4-1 and 4-2 have the generated torque I.
(c) The radial angle (the body portions 4a and 4a' are formed at a 90 degree angle). 'J-4'F-G'!4 a (or 4
a') is the most suitable location, but in this case the thickness increases by the amount of the element 5, so there is no air between the field magnet 2 and the electric (secondary coil 4). The gap increases, making it impossible to obtain a strong torque, and the arrangement is extremely troublesome, making it unsuitable for mass production.Therefore, the element 5 is currently disposed on the lower surface facing the conductor portion 4a.

In order to do this, the magnetoelectric conversion element 5 is disposed on the lower surface of the printed circuit board 2 facing the conductor portion 4a that contributes to the torque generated by the armature coil 4 (see FIG. 4). Screws 15 and 15' made of a magnetic material for fixing the L stator illumination 1 to the top surface of the support column 9b are connected to the armature coil 4-
1.4-2 Conductor portions 4a and 4a' that contribute to the generated torque
, pW; Width per magnetic pole of field magnet 2 n; Width of 1 or more positive polarity in the rotation direction of field magnet 2 (in the direction of arrow A)
. . (see Fig. 5)) and is screwed to a position on the front side (the above-mentioned support column 9b is located at this position). That is, in this first embodiment, as the field (Q magnet 2) uses a four-pole annular magnet having N and S magnetic poles alternately, as shown in FIG. The width pW per magnetic pole is 90 degrees, and the magnetic pole width, which is a quarter of the width pw per magnetic pole, is 22.5 degrees.Therefore, the screw 15 made of magnetic material is In equation (1), if n is selected to be 1, 1 in the circumferential direction is
It is provided at a position toward the front in the rotation direction (direction of arrow A) of the field magnet 2 by an angular width of 12.5 degrees. The screw 15' made of a magnetic material is provided at a position offset clockwise by 112.5& from the conductor portion 4a which contributes to the generated torque of one of the armature coils 4-2. According to the above formula (1), in addition to the position where the screw 15.15' made of the magnetic material is provided, the dotted line enclosure position 40.41 corresponds to the position 40.41, so the screw 15.15' is placed at the position 40.41. You can also screw it on. The reason why the screws 15.15' made of magnetic material are screwed into the above positions is that the screws 15.15' fix the stator armature 1 to the column 9b, and also facilitate the positioning of the protrusions. This is to enable adjustment of the generated force. Such screw 15.15
' causes coking, and even if there is only one magnetoelectric conversion element 5, the rotor can be started automatically. That is, by forming a protrusion made of a magnetic material by the screw 15.15' at the position L, the field magnet 2 is attracted to the protrusion (screw 15.15'), and the field magnet 2 can be activated automatically. (111,
Even if there is only one electric conversion element 5, the two-coil, one-phase disc type brushless fan motor FM can be started automatically. In the embodiment of the right item, a screw 15' is also provided at a position 180 degrees symmetrical to the screw 15 to further enable the rotor to start automatically. The purpose can be achieved even with just one, and it may also be provided at all the positions listed in L. When the screw 15 or 15' is provided, the Ni, Sl, and ffl of the field magnet 2 are attracted and stopped by the screw 15 or 15' so that they are opposed to each other. Therefore, since the magnetoelectric conversion element 5 always detects the N pole or S4M of the field magnet 2, that is, it does not detect the dead point (does not face the dead point), the armature coil 4 -1 or 4-2 in a predetermined direction, the rotor having the field magnet 2 can be rotated in a predetermined direction. Providing protrusions made of a magnetic material on the stator armature 1 inherently causes undesirable coking, but in this disk type brushless fan motor FM, the screws 15. ．． Continuous rotation is made possible by effectively utilizing coking by 15'. Therefore,
Since only one position sensing element is required, an inexpensive disk-type brushless motor or disk-type brushless fan motor that is energized in one phase can be obtained. FIG. 6 shows a torque curve when the motor FM is used at the rated voltage. As is clear from the torque curve in FIG. 6, the relationship between the position of the red ore magnet 2 and the coking torque is shown. At the stable point 45, the coking torque curve 44 cuts a zero point 46 in the right hill direction. This zero point 46 is a so-called dead point, and the zero point 46 and the stable point 45 are equal to one-fourth of the magnetic pole of the field magnet 2, that is, 22.5 degrees. J:.

The stable points 45 appear at four locations in total during one rotation.

There is a zero point 46 where the torque is zero between the stable points 45 and 45, but this zero point 46 is the so-called dead center, and in the present invention, coking torque is generated at this point so that the torque does not become zero. This makes the field magnet 2 unstable, and a slight external force causes the field magnet 2 to rotate in either direction. That is, it can be understood from the fact that the coking torque curve 44 appears due to the four-pole field magnet 2 and the screws 15 and 15' made of magnetic material.

Next, when a current flows through the armature coils 4-1, 4-2, the relationship between the armature torque and the rotation angle becomes an armature torque curve as shown by the symbol 47°47'. This curve 47.47
As is clear from the above, the zero point 46 of ' is slightly to the right of the stable point 45 which is the zero point of the coking torque curve 44 (C
It is in the W force direction. 4 & distortion electric conversion element 5 and the commutation action by the energization control circuit to be described later, the armature torque curve QS
147, 47', and when combined with the coking torque curve 44, a composite torque curve 48 is obtained. Moreover, as mentioned above, there is no dead center and stable operation can be performed. Furthermore, zero point′
Since the coking torque at the 46th position is half of the electric torque, the composite torque curve 48 has an extremely smooth waveform, so the field magnet 2 can rotate smoothly. Therefore, a disk type brushless fan motor FM with good performance can be obtained.

FIG. 7 is a developed view of the field 1 magnet 2 and the stator armature 1 in a brushless (fan) motor with 4 poles, 2 coils, and 1 phase reciprocating energization. Armature coil 4-1
．． 4. Conductor portions 4a, 4a' that contribute to the generated torque of -2
are each 180 degrees in electrical angle (in this example, (
They are arranged at equal intervals with a mechanical angle of 90 degrees. The other terminal of the conductor portion 4a' that contributes to the generated torque of the armature coil 4-1 and one terminal of the conductor portion 4a that contributes to the generated torque of the armature coil 4-2 are commonly connected, and the armature coil 4- 41% portion 4a that contributes to the generated torque of 1
One terminal of the conductor portion 4a' is connected to a connection point 60 between the collector of the transistor 28 and the collector of the transistor 29 in the energization control circuit, and the other terminal of the conductor portion 4a' contributes to the generated l·rook of the armature coil 4-2. is connected to a connection point 66 between the collector of the transistor 61 and the collector of the transistor O2. The energization control circuit is formed as a one-phase reciprocating energization control circuit. The emitters of transistors 28, 31 are each connected to positive power supply terminal 64, and the emitters of transistors 29, 52 are each connected to ground 35. The output terminal 66-1 of the magnetoelectric conversion element 5 is connected to the base side of the transistors 28 and 32 constituting the energization control circuit, and the output terminal 36-2 is connected to the base side of the transistor 50.31. Therefore, when the magnetoelectric converter 5 detects the N pole of the field magnet 2, the output t, '4i element 6
6-1, conducts the transistor 28.32,
A rotational force in the direction of arrow A can be obtained by passing a current in the direction of the arrow through the armature coils 4-1, 4-2.

When the magnetoelectric transducer 5 detects the S pole of the field magnet 2, the transistors 29 and 32 become conductive via the output terminal 66-2, and a current in the opposite direction to the above flows in the armature coils 4i and 4-2. Flow, it is possible to obtain rotational force in the direction of the arrow.

A second embodiment of the present invention will be described with reference to FIGS. 8 to 10. Fig. 8 is a plan view of 6 other annular field magnets (magnet rotors) 2', and Fig. 9 is a plan view of the stator electric field (magnetic rotor 1) consisting of 2 armature coils 4-1, 4-2. The magnetic element 5 is arranged on the printed circuit board 6 at a position equivalent to the i2-in body part 4a that contributes to the torque generated by the armature coil 4-1 (9th
(see figure). The screw 15°15' is screwed into the position of the printed circuit board B according to the above formula (1). Also, Book L (1)
It goes without saying that the child 15.15' may be screwed to the position 16.17 of the dotted line 1 m apart according to the formula.

FIG. 10 is a developed view of a six-pole field magnet 2' and two armature coils 4-1, 4-2. i7) 1st
In Figure 0, a conductor portion 4a contributes to the generated torque of one of the electric forceps coils 4-'I and 4-2.

4a are connected to connection point 30°63 in the energization control circuit, and 11J, 44M child coils 4-1 and 4-2
The conductor portion 4a that contributes to the generated torque of each other
/ and 4 a/ are commonly connected. In addition, electricity is supplied! I
Since the IJ jτ01 circuit has been explained with reference to FIG. 7, its details will be omitted. The magnetoelectric conversion element 5 is L
In the first embodiment, the case is shown in which the conductor section 4a is disposed at the lower surface position of the conductor part 4a which contributes to the torque generated by the armature coil 4-1, but it may not be possible to dispose it at such a position depending on the configuration of the motor. Further, the magnetoelectric conversion element 5 includes the armature coil 4-1
As mentioned above, the conductor portion 4a cannot be placed on the hill that contributes to the generated torque. Therefore, in this second embodiment, armature coil 4-1 is
Considering the magnetoelectric transducer 5 to be disposed at the dotted line enclosure position 67 facing the conductor part 4a that contributes to the generated torque, the dotted line enclosure area 1a67 is the N pole 2'a of the field magnet 2'.
Therefore, if we search for a position with conditions equivalent to the dotted line enclosure position 67, we will find the N pole 2'C9.
Dotted line enclosure position 41.4 which is approximately the middle position of 2'e
0 is applicable. However, since the dotted line surrounding portion position 40 faces the conductor portion 4/a that contributes to the generated torque of the armature coil 4-2, the magnetoelectric transducer 5 is located at the position 40 in the same manner as described above.
However, since the dotted line enclosure position 41 does not face the armature coils 4-1 and 4-2, it is possible to arrange the magnetoelectric transducer 5 on the surface of the printed circuit board 6 corresponding to the position 41. is shown in FIG. Also, 't=f) The conductor portion 4/ which contributes to the trapped raw torque of the A coil 4-1, 4-2.
Considering the positions 38 and 39 of the dotted line enclosure corresponding to a as a reference, S(M2'b) of the field magnet z.

Since it faces approximately the middle part of 2'd, when searching for a position with conditions equal to the straightness of the bend, the dotted line enclosure part position 42, which faces approximately the middle part of S Cfg 2'f, corresponds. So,
The magnetoelectric conversion element 5 may be arranged on the surface of the printed circuit board 3 corresponding to the position 42.

11 to 13 show a third embodiment of the present invention. In this embodiment, as shown in FIG. 11, an eight-pole field magnet 7 having N and S magnetic poles alternately is used. Ori,
As shown in FIG. 12, the armature coils 4-1 and 4-2, in which the opening angle of the radial conductor portions 4a and 4'a that contribute to the generated torque are formed at 45 degrees, are arranged on a printed circuit board 180 degrees symmetrically. This uses stator armatures 1 arranged on six sides. FIG. 13 shows the field magnet 7 and the first magnet in FIG.
This is a developed view of the stator armature 1 in FIG. 2, and since it can be understood by referring to the above example, an explanatory diagram thereof will be omitted. The magnetic bodies such as the screws ts and is' are the armature coil 4.
The above (
If you select based on 1), the dotted line enclosure position 49. ...9
56 corresponds to this, so it would be sufficient to arrange it at this position. Figure 14 shows a plan view of the stator armature 1 showing the fourth embodiment of the present invention, and corresponds to Figure 4. However, instead of using two separate electric<mF coils 4-1.4-2 as shown in Fig. 4, a rotation torque similar to that of the two armature coils 4-1.4-2 is used. The difference is that an armature coil 4' in which two armature coils are combined into one shape is used so that the electric current can be generated. 1st
The armature coil 4' shown in Figure 4 is a four-pole field magnet 2.
(See Fig. 5) It is formed into a frame-shaped coil in the shape of a planar gourd. This armature coil 4' is arranged on the printed circuit board B. Inclined conductor portions 4'a, ..., 4'a''' of armature coil 4'
are the conductor parts that contribute to the generated torque, and the four body parts 4 in the outer circumferential direction
'b, 4'b' and the conductor portion 4 that contributes to the generated torque
Conductor gB between 'a' and 4'a', between 4'a'' and 4'aN
4'b", 4'b"" are conductor parts that do not contribute to the generated torque. Incidentally, Ee child coils 4' having such a shape can be easily mass-produced using a winding machine, but the number is small. In the case of manual production, the armature coil 4' is formed into a rectangular frame shape, and the conductor part 4'b''4/b/// is placed in a plane facing the opposing child coil 4'. The symbols N and S are attached to the outer periphery of FIG. 14 so that the relationship between pole field magnet 20) I'J IM e S k can be understood. As is clear from the above description, the screw 15°15' which generates the coking force is screwed into the position determined based on the above formula (1). Furthermore, based on the above equation (1), since the dotted line surrounding portion positions 57 and 58 correspond, screws 15 and 15' made of a magnetic material may be IU'Med at the overlapping positions.

In addition, the armature coil 4' includes one conductor section including conductor sections 4/a, 4/a/ that contribute to the generated torque (also includes conductor sections 4/i, - that do not contribute to the generated torque). 4′A” and the conductor portion 4′a” that contributes to the generated torque
, 4'a'' (including the conductor section 4'b'' which does not contribute to the generated torque) 4'B and N4
It is formed in such a shape that it can face two magnetic poles, ``ri'' and s. Furthermore, the opening angles of the conductor portions 4'a and 4'f and 4'a' and 4/a/P/, which contribute to the generated torque, are formed to be approximately equal to the magnetic pole width of the field magnet 2.

Therefore, even with one armature coil 4', compared to the conventional two
It is possible to generate rotational torque similar to that obtained by using two electric coils (4-1, 4-2).

In this way, the armature coil 4' in the fourth embodiment is configured such that the field magnet 2 is N or It is characterized by having a small Sfk (both are formed in a shape that can face two magnetic poles.The developed view of this M, a 4 & child coil 4' and the field magnet 2 is the same as shown in FIG. 7, so its explanation will be omitted.

FIG. 15 shows a fifth embodiment of the present invention, which corresponds to FIG. 12, in which one armature coil 4'' is formed into a rectangular frame shape that can be easily formed. Although it is a single armature coil 4'', it is devised so that it can generate the rotational torque of two conventional armature coils 4-1 and 4-2, similar to the parent-child coil 4. However, it was formed into a rectangular frame shape like this. Although the generated torque is slightly lower, it has the advantage of being able to rotate smoothly. Screw 1
515' is arranged based on the above equation (1), and based on the above equation (1), the dotted line surrounding portion position 59. ...,
In order for 62 to generate other coking, screw 151
5' indicates another suitable position for screwing. In the case of Fig. 15, there are two other positions suitable for causing coking, but in this case, the positions overlap armature coil l, so they are not very desirable. Such locations are not shown in FIG. 15.

As is clear from Section E, even with just one position sensing element, the coking force can be generated at the most suitable location, so it is efficient and inexpensive, and can be self-starting, as well as stable rotation. This has the effect of making it possible to obtain a brushless (fan) motor suitable for mass production. Although the above example has been explained using a disc type brushless fan motor as an example, the present invention is naturally applicable to other disc type brushless motors. Further, although the armature coil has been described using an example in which a conducting wire is wound, a coil formed by a printed pattern (so-called sheet coil) may also be used.

Furthermore, it is also applicable to those in which the armature coils overlap in two or three layers. In addition, although we used a field magnet with an annular shape in which multiple magnetic poles were integrated, separate magnets may also be used.1Also, in order to generate coking, a screw made of magnetic material may be used. However, the present invention is not limited to this, and other magnetic materials such as those that can be attached to a printed circuit board using an adhesive may also be used.
It goes without saying that the coking-generating magnetic material does not need to be provided at the stator or single-stock position such as a printed circuit board, and may be formed at a fixed side position on the outer periphery of the field magnet.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal cross-sectional view of a disk-type brushless fan motor shown as an example; FIG. 2 is a perspective view of the case of the disk-type brushless fan motor shown in FIG. 1; and FIG. 3 is a cup body with a fan shown in FIG. 1. FIG. 4 is a plan view of the stator wire according to the first embodiment, and FIG.
i! The bottom view of the magnetic magnet, Figure 6 shows the torque curve when a disc-type brushless fan motor is used at the rated voltage, and Figure 7 shows the field of a disc-type brushless fan motor with 4 poles, 2 coils, and 1-phase reciprocating current. A developed view of a magnetic magnet and an armature coil group (stake armature), Fig. 8 is a bottom view of a 6-pole field magnet used in the second embodiment of the present invention, and Fig. 9 is a second embodiment of the present invention. Fig. 10 is a developed view of the field magnet and armature coil group of a brushless motor with six poles, two coils, and one phase reciprocatingly connected, and Fig. 11 is a plan view of the stator armature of the third embodiment of the present invention. The bottom view of the field magnet 8 used in the example, Figure 12 is a plan view of the stator armature when the field magnet in Figure 11 is used, and the 13th section is the field magnet in Figure 11 and the 12th section. 14 and 15 are plan views of the stator armature of the fourth and fifth embodiments of the present invention, respectively. 1... Stator armature, 2.2' , 2'...° non-rest part contributing to the field magnet torque, 5... has an electric transformer surface (1...
11 Takahashi ” ” @ Figure 2 Figure 3 Figure 4 Figure 5 Figure 6 Figure 7 Kasumi Figure 8 Figure 11 Figure 12 Figure 13 Figure 14

Claims (1)

[Claims] A 21) (p is an integer of 2 or more) pole magnet rotor having 1, N, and S magnetic poles alternately, and a magnet rotor provided on the stator side facing the magnet rotor. a stator armature consisting of at least one armature coil in which the opening angle of two conductor parts contributing to the generated torque is formed to have an opening angle width substantially equal to the magnetic pole width of the magnet; and one position detection element. In the case of a brushless motor having one position sensing element having a position sensing element and a means for generating coking so that the magnetic rotor can self-start, the means for generating coking is based on the coking of the magnetic rotor. From the isobody part that contributes to the generated torque of the armature coil in the direction of rotation, the following equation is obtained: 1. A disc-type brushless motor having one position sensing element, characterized in that coking occurs at a position in front of the throat. 2. A disk-type brushless motor having one position detection element as set forth in claim 1, wherein the means for generating L coking is formed by providing a projection made of a magnetic material at the above-mentioned position. . 3. A disk type having one position sensing element as set forth in claim 2, wherein the protrusion made of a magnetic material is a screw for attaching the stator coin to a fixing member. brushless motor.