JP5032252B2 - motor - Google Patents

Description

  The present invention relates to a motor configured by using field magnets that are different in size according to the arrangement location.

  2. Description of the Related Art In-vehicle electric motors such as wiper motors and power window motors have recently been increasingly required to be thin (flattened) for reasons of vehicle mounting. In order to cope with this, a simple downsizing, and making the yoke housing thin with a flat cylindrical shape with two field magnets (a pair of different magnetic poles) reduces the magnetic field strength on the field side and reduces the torque. This is not a good idea. Thus, for example, Patent Document 1 discloses a technique for reducing the thickness of a motor while maintaining torque.

The motor shown in Patent Document 1 has four magnetic poles on the field side, but the S-pole magnet is omitted, and the N-pole magnet is configured to compensate for the omitted S-pole. .
Specifically, the N-pole magnets are respectively disposed at positions facing each other in the yoke housing at 180 °, and the S-pole magnets that are supposed to be respectively disposed at the facing portions in the direction orthogonal to the facing direction of the N-pole magnets are Omitted, a pseudo magnetic pole portion in which the S pole appears is formed at the opposite portion. The pseudo magnetic pole part is bent so that a part of the yoke housing is close to the rotary armature by an equiangular range with the N pole magnet so that the air gap with the rotary armature is equal to the N pole magnet part. Thus, an S pole magnetic field is generated in the pseudo magnetic pole portion based on the supply of the magnetic flux of the N pole magnet through the yoke housing. Note that the N-pole magnet is formed by being thickened or strongly magnetized by the amount corresponding to the S pole that is omitted.

By configuring in this way, field poles capable of applying a sufficient magnetic field are arranged continuously in the circumferential direction including the pseudo magnetic pole portion, and the S pole is omitted while maintaining the magnetic field strength on the field side. The magnet housing space can be formed in a thin shape (flat type) in which the yoke housing is crushed inward, so that the motor can be reduced in thickness. Further, even if the N-pole magnet is thickened to maintain the magnetic field strength on the field side, it does not affect the direction in which the thinning is hindered.
Japanese Patent Laid-Open No. 2007-12485

  By the way, although the motor of Patent Document 1 has the same configuration on the magnetic circuit as the motor having the normal configuration using the N-pole magnet and the S-pole magnet, a part of the yoke housing is merely a rotating electric machine as the pseudo magnetic pole portion. Due to the configuration close to the child, the short circuit of the magnetic flux due to the armature reaction that occurs when the rotary armature is energized increases. As a result, the magnetic flux distribution is greatly disturbed, which may result in a significant reduction in motor characteristics.

  The present invention has been made in order to solve the above-described problems. The object of the present invention is to use field magnets that are different in size while reducing the size of the field magnet in accordance with the arrangement location and reducing the thickness of the motor. It is another object of the present invention to provide a motor having good magnetic balance and good motor characteristics.

  In order to solve the above-mentioned problem, the invention according to claim 1 is arranged to face each other in a direction intersecting the facing direction of the first magnet and a pair of first magnets facing the inner surface of the yoke member. The motor includes a field magnet having an equal angle range with a second magnet, and a rotating armature rotatably disposed inside the field pole, wherein the yoke member is connected to a pair of flat surfaces parallel to each other. The first magnet is formed in a flat cylindrical shape having a pair of arc portions connecting between the opposite end portions of each flat portion and the first magnet, and the first magnet formed larger than the second magnet is disposed on the arc portion side. The gist of the present invention is that each of the second magnets formed to be smaller is disposed on the flat portion side, and the shortage of the magnetic flux of the second magnet is added to the first magnet side.

  In this invention, the yoke member is formed in a flat cylindrical shape having a pair of flat portions parallel to each other and a pair of arc portions connecting between opposite end portions of each flat portion, and is formed larger than the second magnet. The magnet is disposed on the arc portion side, and the second magnet formed smaller than the first magnet is disposed on the flat portion side. That is, since the second magnet disposed on the flat portion side is configured to be small, a thin yoke member in which the flat portions are close to each other is obtained. In addition, since the shortage of the magnetic flux of the second magnet is added to the first magnet side, the magnetic flux distribution when the rotating armature is not energized is configured to have the same shape as the first and second magnets. The magnetic flux distribution due to the armature reaction is sufficiently suppressed by using the second magnet even if it is small, and the magnetic balance is good even when the rotating armature is energized, and the thickness is reduced as described above. Good motor characteristics can be obtained while aiming.

  According to a second aspect of the present invention, in the motor of the first aspect, the first and second magnets are composed of different magnetic poles, and the field magnetic pole is composed of four magnetic poles. To do.

  In the present invention, the first and second magnets are composed of different magnetic poles, and the field magnetic poles are composed of four magnetic poles. In other words, if the N pole magnet is arranged on the arc portion side of the yoke member, the S pole magnet formed smaller than the N pole magnet is arranged on the flat portion side of the yoke member, and the magnetic flux of the S pole magnet is insufficient. The configuration is added to the N-pole magnet side. In such a motor having four magnetic field poles, the same effect as that of the first aspect can be obtained.

  According to a third aspect of the present invention, in the motor according to the first or second aspect, the first and second magnets are formed of the same magnetic material, and a shortage of magnetic flux of the second magnet is the first. The gist of the present invention is that the thickness is added to the magnet side.

  In the present invention, the first and second magnets are formed of the same magnetic material, and the shortage of the magnetic flux of the second magnet is added to the first magnet side as a thickness. Thereby, while being able to make the material used for a magnet common, it can respond easily by adding the shortage of magnetic flux of the 2nd magnet to the 1st magnet side simply as thickness.

  According to a fourth aspect of the present invention, in the motor according to any one of the first to third aspects, the second magnet is a remaining portion that is cut off in a shape by a flat portion of the yoke member from a predetermined arc shape. The gist is that the part is arranged as the second magnet.

  In the present invention, the remaining portion of the second magnet cut out in a shape from the predetermined arc shape by the flat portion of the yoke member is disposed as the second magnet. As a result, the opposing relationship between the first magnet and the rotating armature and the opposing relationship between the second magnet and the rotating armature are the same, which can contribute to the improvement of the motor characteristics and the lack of magnetic flux of the second magnet. It is also possible to simply add the minute amount to the first magnet side.

The gist of the invention described in claim 5 is that, in the motor described in any one of claims 1 to 4, the second magnet is divided at one magnetic pole.
In this invention, since the 2nd magnet is divided | segmented in one magnetic pole, it can contribute to thickness reduction of a yoke member more.

A sixth aspect of the present invention is the motor according to any one of the first to fourth aspects, wherein the second magnet is formed continuously in one magnetic pole.
In the present invention, since the second magnet is continuously formed in one magnetic pole, the increase in the number of components is suppressed, and the magnetic flux generated in the second magnet is increased, so that the magnetic flux is short-circuited by the armature reaction. It can be suppressed and can contribute to the improvement of magnetic balance.

  A seventh aspect of the present invention is the motor according to any one of the first to sixth aspects, wherein a part or all of the second magnet is integrally formed with the first magnet. The gist.

In the present invention, the second magnet is partly or wholly formed integrally with the first magnet, so that an increase in the number of parts can be suppressed.
The invention according to claim 8 is the motor according to claim 7, wherein the first and second magnets are formed in a single ring shape.

In the present invention, since the first and second magnets are formed in a single ring shape, the field magnet needs only one component, and a sufficient component reduction effect can be obtained.
The gist of the invention according to claim 9 is that, in the motor according to any one of claims 1 to 8, the yoke member is set such that the arc portion is thicker than the flat portion. .

  In the present invention, the yoke member is set such that the arc portion is thicker than the flat portion. That is, it is possible to contribute to the thinning of the yoke member by making the flat portion thin while more surely preventing magnetic saturation at the arc portion where the large first magnet is arranged.

  According to a tenth aspect of the present invention, in the motor according to any one of the first to ninth aspects, in the yoke member, a central portion of the flat portion has a gap corresponding to an air gap with the rotary armature. The gist is that the position is set.

  In this invention, the yoke member is set at a position where the central portion of the flat portion has a gap corresponding to the rotary armature and the air gap. That is, it can be formed as a thin yoke member in which the opposed flat portions are very close to each other.

  The gist of the invention described in claim 11 is that the motor described in any one of claims 1 to 10 is a wiper motor or a power window motor which is an in-vehicle electric motor.

  In the present invention, it is significant to apply the motor according to any one of claims 1 to 9 that can be configured to be thin to a wiper motor or a power window motor that is highly required to be thin.

  According to the present invention, a motor capable of obtaining good motor characteristics with good magnetic balance even when different field magnets are used while reducing the size of the field magnet according to the arrangement location and making the motor thinner. Can be provided.

DESCRIPTION OF EXEMPLARY EMBODIMENTS Hereinafter, an embodiment of the invention will be described with reference to the drawings.
As shown in FIG. 1, a motor 1 of this embodiment is a wiper motor that operates a wiper (both not shown) for wiping a window glass of a vehicle, and includes a motor main body 2 composed of a DC motor, and the motor main body 2. The speed reduction part 3 which decelerates the rotation generated by the worm wheel 4 and transmits it to the output shaft 5 is integrally assembled.

  As shown in FIG. 2, the motor main body 2 includes a bottomed flat cylindrical yoke housing 10 having a pair of flat portions 10a parallel to each other and a pair of arc portions 10b connecting the opposing ends of the flat portions 10a. have. The yoke housing 10 of the present embodiment is formed as thin as possible so that the central portion of the flat portion 10a is located at a position having a gap corresponding to an air gap with a rotary armature 15 (armature core 17) described later. Yes.

  A pair of N-pole magnets 11a and 11b and a pair of two S-pole magnets 12a1, 12a2, 12b1, and 12b2 that are paired in pairs are disposed as field magnets on the inner surface of the yoke housing 10. . The N pole magnets 11a and 11b and the S pole magnets 12a1, 12a2, 12b1, and 12b2 are formed of the same magnetic material. Incidentally, the “N-pole magnet” means that the surface facing the rotating armature 15 described later becomes the N-pole, and the “S-pole magnet” means the surface facing the rotating armature 15 becomes the S-pole. Is. The N-pole magnets 11a and 11b are each formed in an arc shape following the shape with an arc length (approximately 90 ° range) substantially equal to the arc portion 10b, and are fixed to the inner side surfaces of the arc portions 10b. Are arranged opposite to each other.

  The two S pole magnets 12a1 and 12a2 are fixed to the inner surface of one flat portion 10a so as to form a pair of two magnetic poles, and the two S pole magnets 12b1 and 12b2 are similarly provided. In order to form one magnetic pole as a set, it is fixed to the inner surface of the other flat portion 10a. In other words, the S-pole magnets 12a1 and 12a2 and the S-pole magnets 12b1 and 12b2 forming a pair are arranged to face each other in a direction orthogonal to the facing direction of the N-pole magnets 11a and 11b. Each of the S-pole magnets 12a1 and 12a2 and the S-pole magnets 12b1 and 12b2 is formed in a substantially triangular shape that is cut by the flat portion 10a of the yoke housing 10 from an arc shape in the same angular range as the N-pole magnets 11a and 11b. The triangular portion that has been cut off and remains in the yoke housing 10 is disposed at the same position as when originally disposed as an arc-shaped magnet.

  Here, since the S-pole magnets 12a1, 12a2, 12b1, and 12b2 are cut by the flat portion 10a of the yoke housing 10 from the original arc shape, the magnetic flux generated by them is reduced. , 11b is increased, and the insufficient magnetic flux is compensated from the N-pole magnets 11a, 11b to the S-pole magnets 12a1, 12a2, 12b1, 12b2 via the yoke housing 10. Thereby, the magnetic field strength of the whole field is maintained. Incidentally, the broken-line circle shown in FIG. 2 is a circumscribed circle in the case where the N-pole magnet and the S-pole magnet are formed in the same shape by an arc, and the yoke housing 10 remains in the width direction even if the N-pole magnets 11a and 11b are thickened. It is shown that the housing 10 is thin in the thickness direction. As the N pole magnets 11a and 11b are increased in thickness, the arc portion 10b may be formed thicker as shown by the two-dot chain line in FIG. The N-pole magnets 11a and 11b and the S-pole magnets 12a1, 12a2, 12b1, and 12b2 form four magnetic poles in an equiangular range on the field side, and the rotary armature 15 is rotatably accommodated inside thereof. Has been.

  The rotating armature 15 is fixed to an armature core 17 in which 14 teeth 17a are radially extended at an equal angular interval with respect to the rotating shaft 16, and the conductor 18x has three teeth 17a as shown in FIG. 14 windings 18, that is, 14 magnetic poles (not shown in FIG. 2). The rotating armature 15 is provided with a commutator 19 that is fixed to the rotating shaft 16. The commutator 19 has the same number of 14 segments 19a as the teeth 17a, and a predetermined segment 19a and a predetermined winding 18 (conductive wire 18x) are connected to each other. The segments 19a are short-circuited with each other by a short-circuit line 20 so as to have the same potential at intervals of 180 °. A positive-side power supply brush 21a disposed on the magnetic pole center line of the N-pole magnet 11a and a negative-side power supply brush 21b disposed on the magnetic pole center line formed by the S-pole magnets 12a1 and 12a2 (both brushes 21a, The space between 21b is in contact with the segment 19a of the commutator 19, and power is supplied from the outside for rotation of the rotary armature 15 to the windings 18.

In the motor 1 of this embodiment having such a configuration, the magnetic flux distribution in the range of 0 ° to 180 ° is as shown in FIG.
When the rotary armature 15 is not energized, as shown by a broken line in FIG. 4, the magnetic flux distribution is only on the field side, and the magnetic flux distribution is the same as that of a motor having a normal configuration using the same N-pole / S-pole magnet. Is shown. In other words, the thicknesses of the N-pole magnets 11a and 11b with respect to the S-pole magnets 12a1, 12a2, 12b1, and 12b2 are set so as to be the same as those of a motor having a normal configuration. It is possible to change the N-pole magnets 11a and 11b to a magnetic material having a higher residual magnetic flux density.

  At the time of energization of the rotary armature 15, there is a concern about the disturbance of the magnetic flux distribution due to the armature reaction that affects the motor characteristics, but as shown by the solid line in FIG. 4, the disturbance on the N pole side is small in this embodiment, The S pole side is within a sufficiently permissible range although there is some disturbance compared to the N pole side. This is considered to be because short-circuiting of the magnetic flux due to the armature reaction is sufficiently suppressed by using the S-pole magnets 12a1, 12a2, 12b1, and 12b2 even though they are small.

  Incidentally, the magnetic flux distribution when the rotating armature is energized in the motor (see Patent Document 1) in which the S pole magnet is omitted and the pseudo magnetic pole portion is formed in the yoke housing is shown by a one-dot chain line in FIG. Become. In the motor in which the S pole magnet is omitted, the N pole side is also disturbed, and the disturbance is extremely large on the S pole side. This is presumably because the short-circuit of the magnetic flux due to the armature reaction cannot be suppressed at all by omitting the S-pole magnet, which excessively affects the magnetic flux distribution. In an aspect in which this S-pole magnet is omitted, the motor can be thinned, but the magnetic balance is poor and the motor characteristics are deteriorated. On the other hand, the motor 1 of the present embodiment has a configuration in which the motor (yoke housing 10) is thin and the magnetic balance is good and good motor characteristics are obtained.

Next, characteristic effects of the present embodiment will be described.
(1) In the present embodiment, the yoke housing 10 is formed in a relatively simple bottomed flat cylindrical shape having a pair of flat portions 10a and a pair of arc portions 10b, and N-pole magnets 11a, 11b (first Magnets) are arranged on the arc portion 10b side, and S-pole magnets 12a1, 12a2, 12b1, 12b2 (second magnet) are arranged on the flat portion 10a side. That is, since the S-pole magnets 12a1, 12a2, 12b1, and 12b2 disposed on the flat portion 10a side are configured in a small size, the thin yoke housing 10 in which the flat portions 10a are close to each other is formed. In addition, the magnetic flux distribution when the rotating armature 15 is not energized is N because the magnetic flux deficiency of the S pole magnets 12a1, 12a2, 12b1, 12b2 is added to the N pole magnets 11a, 11b. The magnetic flux distribution is the same as when the pole and S pole magnets are configured in the same shape, and even with a small size, the use of the S pole magnets 12a1, 12a2, 12b1, and 12b2 sufficiently suppresses short-circuiting of the magnetic flux due to the armature reaction. Even when the armature 15 is energized, the magnetic balance is good, and the motor 1 can have good motor characteristics while being thin as described above. In addition, it is significant to apply the motor 1 that can be configured in this way to a wiper motor that is highly demanded of thickness reduction.

  (2) In this embodiment, the N-pole magnets 11a and 11b and the S-pole magnets 12a1, 12a2, 12b1, and 12b2 are formed of the same magnetic material, and the magnetic flux of the S-pole magnets 12a1, 12a2, 12b1, and 12b2 is insufficient. Is added to the N-pole magnets 11a and 11b as thickness. As a result, the materials used for the magnet can be made common, and the magnetic flux deficiency of the S-pole magnets 12a1, 12a2, 12b1, 12b2 can be easily dealt with by simply adding the thickness to the N-pole magnets 11a, 11b side. Can do.

  (3) In the present embodiment, the S-pole magnets 12a1 and 12a2 and the S-pole magnets 12b1 and 12b2 have the remaining arcuate portions originally cut out from the predetermined arc shape by the flat portion 10a of the yoke housing 10. It is arranged at the same position as when it was arranged as a magnet. As a result, the opposing relationship between the N-pole magnets 11a and 11b and the rotary armature 15 and the opposing relationship between the S-pole magnets 12a1, 12a2, 12b1, and 12b2 and the rotary armature 15 are the same, so that the motor characteristics are improved. In addition, the shortage of magnetic flux of the S pole magnets 12a1, 12a2, 12b1, 12b2 can be simply added to the N pole magnets 11a, 11b side.

  (4) In the present embodiment, since the S pole magnets 12a1 and 12a2 and the S pole magnets 12b1 and 12b2 are divided at one magnetic pole, the yoke housing 10 can be made thinner.

  (5) As shown by a two-dot chain line in FIG. 2, the yoke housing 10 of the present embodiment is set so that the arc portion 10b is thicker than the flat portion 10a, thereby arranging large N-pole magnets 11a and 11b. The yoke housing 10 can be thinned by making the flat portion 10a thin while more reliably preventing magnetic saturation in the arc portion 10b.

  (6) In the present embodiment, the yoke housing 10 is set at a position where the central portion of the flat portion 10a has a gap corresponding to the rotary armature 15 and an air gap. That is, it can be formed as a thin yoke housing 10 in which the opposed flat portions 10a are very close to each other.

In addition, you may change embodiment of this invention as follows.
In the above embodiment, the N pole magnets 11a and 11b are set as the first magnet and the S pole magnets 12a1, 12a2, 12b1 and 12b2 are set as the second magnet. However, the magnetic poles may be replaced.

  In the above embodiment, the S-pole magnets 12a1 and 12a2 that constitute one magnetic pole and the S-pole magnets 12b1 and 12b2 that also constitute one magnetic pole are divided, respectively. It may be changed as follows.

  In FIG. 5, S pole magnets 12a1 and 12a2 constituting one magnetic pole are constituted as one continuous S pole magnet 12a, and S pole magnets 12b1 and 12b2 constituting one magnetic pole are constituted as one continuous S pole magnet 12b. May be. In this case, the yoke housing 10 is slightly enlarged in the thickness direction (the space between the flat portions 10a is widened), and the S-pole magnets 12a and 12b that are continuous with one magnetic pole can be arranged. By adopting this configuration, an increase in the number of components is suppressed, and the magnetic flux generated by the S-pole magnets 12a and 12b is increased. Therefore, a short circuit of the magnetic flux due to the armature reaction can be further suppressed, which contributes to the improvement of the magnetic balance. be able to. In this case, the thickness of the N-pole magnets 11 a and 11 b can be reduced by the amount of magnetic flux generated by the S-pole magnets 12 a and 12 b, and the yoke housing 10 can be reduced in size in the width direction.

  In FIG. 6, the S pole magnet 12a1 and the S pole magnet 12b2 are formed integrally with the N pole magnet 11a, and the S pole magnet 12a2 and the S pole magnet 12b1 are formed integrally with the N pole magnet 11b. With this configuration, an increase in the number of components can be suppressed.

  Further, in FIG. 7, the S pole magnets 12a and 12b that are made continuous with one magnetic pole are further integrated with the N pole magnets 11a and 11b to form a single ring, so that only one part of the field magnet is required. A sufficient component reduction effect can be obtained.

  In the above embodiment, the present invention is applied to the four-pole motor 1 including the N-pole magnets 11a and 11b, the S-pole magnets 12a1 and 12a2, and the S-pole magnets 12b1 and 12b2, but may be applied to, for example, a six-pole motor. . In this case, a pair of N-pole magnets and S-pole magnets that face each other correspond to the first magnets, and the N-poles between the first magnets arranged to face each other in a direction intersecting the facing direction of the first magnets. Each S pole magnet corresponds to a second magnet.

  In the above embodiment, the present invention is applied to the motor 1 using the yoke housing 10 having a housing function. However, the present invention is applied to a motor using a yoke member that does not have a housing function and has a cylindrical shape at least with only a magnet portion. May be.

  -Although it applied to the motor 1 of a wiper motor in the said embodiment, you may apply to other vehicle-mounted electrical motors, such as a motor for power windows. Moreover, you may apply to motors other than a vehicle-mounted electrical motor.

It is a schematic block diagram of the motor in this embodiment. It is sectional drawing which shows the cross section of a motor main body. It is an expanded view which shows the electromagnetic structure of a motor main body. It is a wave form diagram for demonstrating a motor characteristic. It is sectional drawing which shows the cross section of the motor main body in another example. It is sectional drawing which shows the cross section of the motor main body in another example. It is sectional drawing which shows the cross section of the motor main body in another example.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 1 ... Motor, 10 ... Yoke housing as a yoke member, 10a ... Flat part, 10b ... Arc part, 11a, 11b ... N pole magnet as 1st magnet, 12a1, 12a2, 12b1, 12b2, 12a, 12b ... 2nd S pole magnets as magnets, 15 ... rotating armature.

Claims (11)

A pair of first magnets arranged opposite to the inner surface of the yoke member and a second magnet arranged opposite to the direction in which the first magnet faces are configured to form field magnetic poles in an equiangular range. A motor in which a rotating armature is rotatably arranged inside a field magnetic pole,
The yoke magnet is formed in a flat cylindrical shape having a pair of flat portions parallel to each other and a pair of arc portions connecting between opposite ends of the flat portions, and the first magnet is formed larger than the second magnet. The second magnet formed smaller than the first magnet is disposed on the flat portion side, and a shortage of magnetic flux of the second magnet is added to the first magnet side. A motor characterized by The motor according to claim 1,
The motor according to claim 1, wherein the first and second magnets are composed of different magnetic poles, and the field magnetic poles are composed of four magnetic poles. The motor according to claim 1 or 2,
The first and second magnets are made of the same magnetic material, and a shortage of magnetic flux of the second magnet is configured with the thickness added to the first magnet side. The motor according to any one of claims 1 to 3,
The motor is characterized in that the second magnet is disposed as a second magnet of a remaining portion cut out in a shape by a flat portion of the yoke member from a predetermined arc shape. The motor according to any one of claims 1 to 4,
The motor, wherein the second magnet is divided at one magnetic pole. The motor according to any one of claims 1 to 4,
The motor, wherein the second magnet is formed continuously in one magnetic pole. The motor according to any one of claims 1 to 6,
A part or all of the second magnet is integrally formed with the first magnet. The motor according to claim 7, wherein
The motor according to claim 1, wherein the first and second magnets are formed in a single ring shape. The motor according to any one of claims 1 to 8,
The motor, wherein the yoke member is set so that the arc portion is thicker than the flat portion. The motor according to any one of claims 1 to 9,
The motor is characterized in that the yoke member is set so that a central portion of the flat portion is located at a position corresponding to an air gap with the rotary armature.   The motor according to any one of claims 1 to 10, wherein the motor is a wiper motor or a power window motor that is an on-vehicle electric motor.

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