JPWO2008001689A1 - Motor with brush - Google Patents

Abstract

A yoke insertion piece 28 is projected from the brush holder stay 21 along the axial direction. A magnet 8 and a magnet holder 9 are attached to the yoke inner peripheral surface 7a. Ribs 30 are formed on the outer peripheral surface of the yoke insertion piece 28, and the brush holder stay 21 is lightly press-fitted into the yoke 7. A stay pressing claw 36 is formed in the magnet holder 9, and the yoke insertion piece 28 is sandwiched between the stay pressing claw 36 and the yoke inner peripheral surface 7 a, and the brush holder stay 21 is fixed in the yoke 7. . A flat surface portion 37 is formed on the inner peripheral surface of the yoke insertion piece 28, and the stay pressing claw 36 abuts on the flat surface portion 37.

Description

  The present invention relates to an electric motor using a brush, and more particularly to a fixing structure of a brush holder stay that houses and holds a brush.

  2. Description of the Related Art Conventionally, in an electric motor with a brush, a structure in which a synthetic resin member called a brush holder stay is arranged in the motor in order to accommodate and hold the brush has been adopted. A metal brush holder is attached to the brush holder stay, and the brush is accommodated and held in the brush holder. The brush holder stay is fixed to a yoke, an end bracket or the like of the motor, and the following two methods are generally used as the fixing structure. 10 and 11 are explanatory views showing a fixing structure of a brush holder stay in a conventional motor with a brush. FIG. 10 shows a first method (Patent Document 1), and FIG. 11 shows a second method (Patent Document 2). The fixed structure by is shown.

  First, in the first method, the brush holder stay is fixed to the end bracket by a fixing member such as a rivet. For example, in the motor of FIG. 10, the brush holder stay 51 is fixed to the end bracket 53 by a rivet 52. A brush 54 is accommodated and held in the brush holder stay 51 and is attached to an end portion of a motor yoke (not shown) together with the end bracket 53.

Next, in the second method, the brush holder stay is sandwiched between the yoke and the end bracket. For example, in the motor of FIG. 11, the brush holder stay 55 is sandwiched between the yoke 56 and the end bracket 57. A brush 58 is housed and held in the brush holder stay 55 and is fixed between the yoke and the end bracket when the end bracket 57 is attached to the yoke 56.
Japanese Utility Model Publication No. 61-129453 JP2003-9456

  However, in the first fixing method as shown in FIG. 10, a member (here, a rivet 52) for fixing the brush holder stay 51 and the end bracket 53 is separately required. For this reason, while the number of parts increases, the man-hour for fixing the brush holder stay 51 is needed, and the problem of causing a cost increase arises.

  On the other hand, in the second fixing method as shown in FIG. 11, although a fixing member is not separately required, there is a possibility that the synthetic resin brush holder stay 55 creeps and deforms with time and loosens and looses. is there. In particular, those used in the vicinity of a heat source such as an engine, such as a motor for a fan for cooling a radiator of an automobile, are liable to cause thermal contraction and creep deformation, and measures against mounting backlash have been required. In addition, in-vehicle motors are constantly subjected to vibration during operation, and there is a problem in terms of durability when rattling occurs due to creep deformation.

  An object of the present invention is to fix a brush holder stay in a motor without separately using a fixing member such as a rivet, and to fix the brush holder stay so that no mounting play occurs even if the brush holder stay is deformed due to aging. Is to provide.

  A motor with a brush according to the present invention includes a cylindrical yoke, a plurality of magnets mounted in the yoke, and a stator that is disposed between the magnets and holds a magnet holder in a predetermined position; An armature fixed to the rotating shaft and rotatably disposed in the stator, a commutator fixed to the rotating shaft and electrically connected to the armature, a brush slidably contacting the commutator, and attached to the yoke And a brush holder stay having a brush holder portion for receiving and holding the brush, wherein the brush holder stays in contact with the brush holder stay and holds the brush holder stay in the motor. A possible brush holder stay fixing portion is provided in the magnet holder.

  In the present invention, a brush holder stay fixing portion is provided in a magnet holder that is also present in a conventional motor, and the brush holder stay fixing portion is brought into contact with the brush holder stay so that the brush holder stay is placed in the motor. Hold. As a result, the brush holder stay can be fixed in the yoke without an increase in the number of parts, and the product cost can be reduced. Further, since the brush holder stay is not fixed between the yoke and the end bracket, the attachment of the brush holder stay is not loosened due to creep deformation or the like, and the durability is improved.

  In the motor with brush, the extending portion that extends along the axial direction is provided in the brush holder stay, the brush holder stay fixing portion is in contact with the extending portion, and the extending portion May be sandwiched between the brush holder stay fixing portion and the inner peripheral surface of the yoke.

  Moreover, in the motor with a brush of this invention, you may provide the projection part contact | abutted with the said yoke inner peripheral surface in the outer peripheral surface side of the said extension part. Thus, by providing the protruding portion on the outer peripheral surface of the extending portion, when the brush holder stay is assembled in the yoke, when the extending portion is inserted into the yoke, the protruding portion abuts on the inner peripheral surface of the yoke, and the brush holder The stay is lightly press-fitted into the yoke. For this reason, even if there is a slight gap between the brush holder stay and the yoke, the looseness is absorbed by the protrusion, and the brush holder stay is attached to the yoke without backlash. Further, since the brush holder stay is temporarily fixed to the yoke even during the mounting operation, the assembling property can be improved.

  On the other hand, in the motor with a brush according to the present invention, the brush holder stay has an extending portion that extends along the axial direction and is inserted into the yoke, and the brush holder stay fixing portion is in contact with the outer peripheral surface of the extending portion. You may contact.

  Furthermore, in the motor with a brush according to the present invention, a flat portion may be provided on the side of the extended portion where the brush holder stay fixing portion abuts. In this case, the plane portion may be arranged at a position corresponding to the advance angle setting of the motor. In this way, by providing a flat portion on the inner peripheral surface of the extending portion and bringing the brush holder stay fixing portion into contact therewith, the brush holder stay fixing portion and the extending portion can be brought into line contact, and the stay holding effect can be improved. Improvement and stability are achieved.

  In addition, in the motor with a brush according to the present invention, the brush holder stay includes a peripheral wall fitted to the inner peripheral portion of the yoke end surface, and a contact surface formed on the inner peripheral side of the peripheral wall and extending toward the center. And the brush holder stay fixing portion may be brought into contact with one or both of the peripheral wall and the contact surface.

  In the motor with brush according to the present invention, the brush holder stay fixing portion may be elastically brought into contact with the brush holder stay. Thereby, for example, even if creep deformation occurs in the extended portion or the like, the brush holder stay is still held in the motor by the elasticity of the brush holder stay fixing portion, and attachment is not loosened. Further, the brush holder stay fixing portion may be formed in a cantilevered plate spring shape, and an adjustment hole for adjusting the elastic force of the brush holder stay fixing portion may be provided in the center thereof.

  According to the brushed motor of the present invention, the magnet holder mounted in the yoke is provided with the brush holder stay fixing portion that comes into contact with the brush holder stay and can hold the brush holder stay in the motor. Further, the brush holder stay can be held in the motor by using the existing magnet holder. For this reason, it becomes possible to fix the brush holder stay in the yoke without backlash without increasing the number of parts, and the product cost can be reduced. Further, in the motor with a brush according to the present invention, since it is not necessary to fix the brush holder stay between the yoke and the end bracket, it is possible to prevent the brush holder stay from being loosened due to thermal contraction or creep deformation, and durability. It is also possible to improve.

It is sectional drawing which shows the structure of the motor with a brush which is Example 1 of this invention. It is explanatory drawing which shows the structure of a brush holder stay. It is a disassembled perspective view which shows the structure of a stay fixing | fixed part. It is an expanded sectional view of a stay fixing | fixed part. It is a front view of a stay fixing | fixed part. It is a top view of a magnet holder. It is explanatory drawing which shows the contact position with the plane part of a stay press nail | claw. It is explanatory drawing which shows the structure of the stay fixing | fixed part of the motor with a brush which is Example 2 of this invention. It is explanatory drawing which shows the structure of the stay fixing | fixed part of the motor with a brush which is Example 3 of this invention. It is explanatory drawing which shows the fixing structure (1st system) of the brush holder stay in the conventional motor with a brush. It is explanatory drawing which shows the fixing structure (2nd system) of the brush holder stay in the conventional motor with a brush.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Motor 2 Stator 3 Armature 4 Brush 5 Rotating shaft 6 Cooling fan 7 Yoke 7a York inner peripheral surface 7b Step part 8 Magnet 9 Magnet holder 11 End bracket 12a, 12b Bearing 13 Core 14 Coil 15 Commutator 16 Commutator piece 17 Brush holder 18 Spring 21 Brush holder stay 22 Main body 23 Brush housing part 24 Pigtail 25 Conductive plate 26 Terminal part 27 Connection terminal 28 Yoke insertion piece (extension part) 28a, 28b Yoke insertion piece 29 Outer peripheral surface 30 Rib (projection part)
31a, 31b Stay fixing part 32 Fixing hole 33 Magnet pressing claw 34 Magnet pressing claw 35 Middle claw 36 Stay pressing claw (Brush holder stay fixing part)
36a Tip portion 36b Elastic force adjusting hole 37 Plane portion 37a Plane portion 38 Motor 39 Stay pressing claw (Brush holder stay fixing portion)
39a Tip part 39b Flat part 41 Yoke insertion piece 41b Yoke insertion piece 42 Holding claw insertion part 43 Flat part 44 Motor 45 Stay holding claw (Brush holder stay fixing part)
45a bent portion 45b extending portion 46 the circumferential wall 46a in the periphery 47 abutting surface 48 stay mounting groove 51 brush holder stay 52 rivet 53 end bracket 54 brush 55 brush holder stay 56 yoke 57 end bracket 58 brush _F 1 to F ₄ elastic holding force

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

  FIG. 1 is a cross-sectional view showing the configuration of a brushed motor that is Embodiment 1 of the present invention. A motor 1 in FIG. 1 is a DC motor with a brush in which an armature 3 is rotatably disposed in a stator 2, and supplies current to the armature 3 through a brush 4. The motor 1 is used as a drive source for a fan for cooling a radiator of an automobile. A cooling fan 6 is attached to the rotating shaft 5 of the motor 1, and when the motor 1 is driven, the cooling fan 6 rotates. Cooling air generated with the rotation of the cooling fan 6 is supplied to a radiator (not shown), and the radiator is cooled.

  The stator 2 includes a bottomed cylindrical yoke 7 and a plurality (four in this case) of magnets 8 fixed to the yoke inner peripheral surface 7a. Four metal magnet holders 9 are fixed to the yoke inner peripheral surface 7a. The magnet holder 9 is equally arranged along the circumferential direction, and each magnet 8 is arranged and fixed at a predetermined position on the yoke inner peripheral surface 7 a by the magnet holder 9. On the other hand, the left end of the yoke 7 in the drawing is open, and an end bracket 11 is attached thereto. Bearings 12 a and 12 b are respectively attached to the center of the end bracket 11 and the center of the right end portion of the yoke 7 in the drawing.

  The armature 3 includes a core 13 formed by laminating a plurality of steel plates and a coil 14 wound around the core 13. The core 13 is fixed to the rotating shaft 5, and the rotating shaft 5 is rotatably supported by bearings 12a and 12b. A commutator 15 is provided on one side of the armature 3 (left side in FIG. 1). The commutator 15 is also fixed to the rotating shaft 5, and a metal commutator piece 16 is disposed around the commutator 15. The commutator piece 16 is electrically connected to the coil 14, and the brush 4 is in sliding contact with the surface thereof. The brush 4 is housed and held in the brush holder 17 so as to be movable along the radial direction, and is urged toward the center by a spring 18. The brush holder 17 is fixed to a brush holder stay 21 made of synthetic resin.

  FIG. 2 is an explanatory view showing the configuration of the brush holder stay 21, and the center is a front view thereof. The brush holder stay 21 includes a main body portion 22 formed of a synthetic resin and four brush housing portions 23 provided on the main body portion 22. A metal brush holder 17 fixed to the main body portion 22 is attached to the brush housing portion 23. The brush holder 17 is equally divided in the circumferential direction, and the brush 4 is accommodated therein so as to be movable along the radial direction. A pigtail 24 is attached to the brush 4, and the pigtail 24 is connected to a conductive plate 25 attached to the main body 22. The conductive plate 25 is electrically connected to a connection terminal 27 of a terminal portion 26 provided on the outer periphery of the main body portion 22.

  Two yoke insertion pieces (extending portions) 28 (28a, 28b) are further provided in the vicinity of the outer periphery of the main body portion 22 along the extending direction (axial direction) of the rotating shaft 5. The yoke insertion piece 28a is provided at the same position as the terminal portion 26, and the yoke insertion piece 28b is provided at a position facing the terminal portion 26 by 180 °. The yoke insertion piece 28 is inserted into the yoke 7 when the brush holder stay 21 is assembled to the yoke 7. The outer circumferential surface 29 of the yoke insertion piece 28 is a circumferential surface and is formed to have a slightly smaller diameter than the yoke inner circumferential surface 7a. The outer peripheral surface 29 is provided with ribs (protrusions) 30 that protrude in the radial direction. The rib 30 has a triangular cross section, and gradually increases in height from the distal end side of the yoke insertion piece 28 to the base side as shown in the lower right diagram (cross section AA) of FIG. In the motor 1, the maximum height at the base of the rib 30 is set to 0.4 mm.

  In the motor 1, when the brush holder stay 21 is assembled to the yoke 7, when the yoke insertion piece 28 is inserted into the yoke 7, the rib 30 contacts the yoke inner peripheral surface 7 a. That is, in the motor 1, the brush holder stay 21 is lightly press-fitted into the yoke 7 such that the rib 30 contacts the yoke inner peripheral surface 7 a. Therefore, even if there is a slight gap between the brush holder stay 21 and the yoke 7, the looseness is absorbed by the rib 30, and the brush holder stay 21 is attached to the yoke 7 without backlash. Therefore, the play in the radial direction of the brush holder stay 21 is suppressed, and the durability is improved. In particular, it is possible to improve the durability of an in-vehicle motor used in an environment with a lot of vibration. Further, since the brush holder stay 21 is temporarily fixed to the yoke 7 during the attaching operation, the assembling property can be improved and the number of assembling steps can be reduced.

  On the other hand, in the motor 1 according to the present invention, the brush holder stay 21 is fixed in the yoke 7 by stay fixing portions 31 a and 31 b using the magnet holder 9. 3 is an exploded perspective view showing the structure of the stay fixing portion 31b, FIG. 4 is an enlarged sectional view of the stay fixing portion 31b, FIG. 5 is a front view thereof, and FIG. 6 is a plan view of the magnet holder 9. Since the two stay fixing portions 31a and 31b have the same configuration, FIGS. 3 to 5 show only the configuration of the stay fixing portion 31b on one side (the upper side in FIG. 1).

  As shown in FIGS. 3 and 6, the magnet holder 9 used in the stay fixing portions 31a and 31b has a fixing hole 32 at the center. The magnet holder 9 is positioned by a positioning protrusion (not shown) protruding from the yoke inner peripheral surface 7 a using the fixing hole 32. A magnet pressing claw (magnet holding portion) 33 is formed on the side surface of the magnet holder 9. A magnet pressing claw (magnet holding portion) 34 is formed on the end surface of the magnet holder 9 on the end bracket 11 side. At the center of the magnet pressing claw 33, an intermediate claw 35 protrudes in a circumferential direction.

  The magnet 8 is attached between the magnet holders 9 fixed to the yoke 7. The magnet 8 is mechanically fixed to the yoke inner peripheral surface 7 a by the elastic force of the magnet pressing claw 33. Thereby, the magnet 8 is clamped between the opposing magnet pressing claws 33 of the adjacent magnet holder 9, and the movement of the magnet 8 in the circumferential direction is restricted. On the other hand, the movement of the magnet 8 attached between the magnet holders 9 is restricted by the magnet pressing claw 34 and the step 7 b (see FIG. 1) formed on the right end surface of the yoke 7.

  The magnet holder 9 is further provided with a stay pressing claw (brush holder stay fixing portion) 36 for fixing the brush holder stay 21. The stay pressing claw 36 is formed at the center of the end surface of the magnet holder 9 on the end bracket 11 side, and protrudes so as to extend in the axial direction. The stay pressing claw 36 is formed in the shape of a cantilever leaf spring, and the distal end portion 36a is bent downward (center direction). An elastic force adjusting hole 36b is formed at the center of the stay pressing claw 36, and the elasticity of the stay pressing claw 36 can be appropriately changed by changing the size of the hole 36b.

  Such a motor 1 is assembled as follows. First, the brush holder stay 21 is placed on the end bracket 11 and the armature 3 is assembled to the end bracket 11. On the other hand, a magnet holder 9 and a magnet 8 are attached to the yoke 7 in advance. Then, the yoke 7 is mounted on the end bracket 11 to which the armature 3 is mounted. At this time, the brush holder stay 21 is assembled to the yoke 7 in a light press-fit state as described above. As shown in FIGS. 3 and 4, when the yoke 7 is attached, the yoke insertion piece 28 (28b in FIGS. 3 and 4) is inserted between the stay pressing claw 36 and the yoke inner peripheral surface 7a. Sandwiched between. Thereafter, the end bracket 11 and the yoke 7 are caulked and fixed, and the motor 1 in the state of FIG. 1 is obtained.

In the motor 1, when the yoke 7 and the end bracket 11 are assembled, the yoke insertion piece 28 is inserted between the stay pressing claw 36 and the yoke inner peripheral surface 7a. At this time, since the tip end portion 36a of the stay pressing claw 36 is bent downward, the yoke insertion piece 28 is smoothly introduced between the stay pressing claw 36 and the yoke inner peripheral surface 7a. When the brush holder stay 21 is further pushed into the yoke 7, the yoke insertion piece 28 advances to the back against the urging force of the stay pressing claw 36 and enters between the yoke inner peripheral surface 7 a. At this time, an elastic holding force F ₁ is applied to the yoke insertion piece 28 from the stay pressing claw 36 toward the outer circumferential direction. By this elastic holding force F ₁ , the yoke insertion piece 28 is sandwiched between the yoke inner peripheral surface 7 a and the stay pressing claw 36, and the brush holder stay 21 is fixed in the yoke 7.

  As described above, in the motor 1 according to the present invention, the stay holder claw 36 is provided on the magnet holder 9 that has existed in the past, and a part of the brush holder stay 21 (this In the embodiment, the yoke insertion piece 28) is elastically clamped to fix the brush holder stay 21 to the yoke 7. For this reason, parts such as rivets are not required, and the brush holder stay 21 can be fixed in the yoke 7 without play without increasing the number of parts. Therefore, the part cost and the assembly man-hour are reduced, and the product cost is reduced accordingly.

  Further, since it is not necessary to fix the brush holder stay 21 between the yoke 7 and the end bracket 11, no loosening due to heat shrinkage or creep deformation occurs, and durability can be improved. In this case, even if creep deformation occurs in the yoke insertion piece 28, the elastic region of the stay pressing claw 36 can be set larger than the creep amount. Therefore, the yoke insertion piece 28 is located between the yoke inner peripheral surface 7 a and the stay pressing claw 36. Still pinched. For this reason, even if creep deformation occurs, the attachment is not loosened, and the occurrence of attachment play can be prevented. Therefore, even in the motor 1 used in the vicinity of the engine, there is no concern of mounting play due to creep deformation or the like, and the durability and reliability of the motor are improved. Since the motor 1 is assembled in a stacked manner with reference to the end bracket 11 as described above, the variation in the dimensions of the brush holder stay 21 is also adjusted at the portion of the yoke insertion piece 28 sandwiched between the stay pressing claws 36. Is done.

  On the other hand, a flat portion 37 is formed in the yoke insertion piece 28, and the stay pressing claw 36 abuts on the flat portion 37. In this case, if the stay pressing claw contact surface of the yoke insertion piece 28 is a circumferential surface, the stay pressing claw 36 may make point contact with the yoke insertion piece 28 and a sufficient stay holding effect may not be obtained. In this respect, in the motor 1, since the flat portion 37 is provided on the yoke insertion piece 28 and the stay pressing claw 36 is brought into contact therewith, the stay pressing claw 36 and the yoke insertion piece 28 are in line contact, and the stay holding The effect is improved and stabilized.

Further, the flat portion 37 is formed at a position inclined by an angle θ with respect to the center line O ₁ (center line located in the middle of the brush 4) of the brush holder stay 21 corresponding to the advance angle of the motor 1. Yes. FIG. 7 is an explanatory view showing a contact position of the stay pressing claw 36 with the flat portion 37. As shown in FIG. 7, the stay holding pawl 36 abuts the flat surface portion 37a provided from the center line O ₁ to the angle θ advanced position. Thus, the plane portion 37 can be appropriately set according to the advance angle of the motor. For example, when the advance angle is 0, a plane portion orthogonal to the center line O ₁ may be provided, and the advance angle adjustment is performed. It can respond flexibly.

  Next, a brushed motor that is Embodiment 2 of the present invention will be described. In the following embodiments, the same members and portions as those in the first embodiment are denoted by the same reference numerals, and the description thereof is omitted.

The motor 38 of the second embodiment has substantially the same configuration as that of the motor 1 of FIG. 1, and the configuration is different only in the stay fixing portions 31a and 31b. FIG. 8 is an explanatory diagram showing the configuration of the stay fixing portion 31b in the motor 38. As shown in FIG. As shown in FIG. 8, in the motor 38, the brush holder stay 21 is held by an elastic holding force F < _b > _{2 of} a stay pressing claw (brush holder stay fixing portion) 39 formed on the magnet holder 9.

  Similarly to the stay presser claw 36 of the motor 1, the stay presser claw 39 also protrudes in the center of the end surface of the magnet holder 9 on the end bracket 11 side so as to extend in the axial direction. On the other hand, the stay presser claw 39 in the second embodiment is different from the stay presser claw 36 in that it is bent one step downward from the base part (center direction), and then a flat part 39b is formed along the axial direction. A front end portion 39a bent upward (in the outer peripheral direction) is formed on the front end side of the flat surface portion 39b.

  On the other hand, a yoke insertion piece 41 (41b in FIG. 8) projects from the brush holder stay 21 side. Unlike the case of the motor 1, the yoke insertion piece 41 is formed at a position slightly inward from the outer periphery of the main body 22. When the yoke 7 and the end bracket 11 are assembled, a pressing claw insertion portion 42 is formed between the outside of the yoke insertion piece 41 and the yoke inner peripheral surface 7a. As shown in FIG. 8, a stay presser claw 39 is disposed in the presser claw insertion portion 42 while being in contact with the outer peripheral surface of the yoke insert piece 41.

  The motor 38 is also assembled in the same manner as the motor 1 described above. When the yoke 7 and the end bracket 11 are assembled, the yoke insertion piece 41 is inserted into the yoke 7. When the brush holder stay 21 is pushed into the yoke 7, the tip of the yoke insertion piece 41 comes into contact with the tip 39 a of the stay pressing claw 39. When the brush holder stay 21 is further pushed in, the yoke insertion piece 41 advances to the back against the urging force of the stay pressing claw 39, and the stay pressing claw 39 enters the pressing claw insertion portion 42 accordingly.

The stay pressing claw 39 that has entered the pressing claw insertion portion 42 has its flat surface portion 39 b elastically abutting against the yoke insertion piece 41. At this time, a flat portion 43 is formed in the yoke insertion piece 41, and the yoke insertion piece 41 and the stay pressing claw 39 are in surface contact. That is, similarly to the motor 1 of the first embodiment, also in the motor 38, the yoke insertion piece 41 is formed with a flat portion 43 on the surface on the side where the stay pressing claw 39 abuts. As a result, an elastic holding force F ₂ from the stay pressing claw 39 toward the center is applied to the yoke insertion piece 41, and the brush holder stay 21 is fixed to the yoke 7 by this elastic holding force F ₂ .

  As described above, also in the motor 38 of the second embodiment, the brush holder stay 21 can be fixed in the yoke 7 without play without increasing the number of parts, similarly to the motor 1 of the first embodiment. Further, since the elastic region of the stay pressing claw 39 can be set larger than the creep amount of the yoke insertion piece 41, even if creep deformation or the like occurs in the yoke insertion piece 41, the holding force can be maintained. It is possible to prevent the occurrence of mounting play.

FIG. 9 is an explanatory diagram illustrating the configuration of the stay fixing portion 31b in the brushed motor 44 according to the third embodiment of the present invention. The motor 44 of the third embodiment also has substantially the same configuration as that of the motor 1 of FIG. 1, and only the portions of the stay fixing portions 31a and 31b are different. As shown in FIG. 9, in the motor 44, the brush holder stay 21 is held by elastic holding forces F ₃ and F ₄ by stay pressing claws (brush holder stay fixing portions) 45 formed in the magnet holder 9.

  The stay pressing claw 45 is also provided in the axial direction at the center of the end surface of the magnet holder 9 on the end bracket 11 side. On the other hand, the stay pressing claw 45 in the third embodiment is bent one step downward from the base, and then extends along the axial direction to form a substantially semicircular bent portion 45a. The stay pressing claw 45 changes its extending direction at the bent portion 45a, and the extending portion 45b extends further downward. On the other hand, the yoke insertion piece 41 is not formed on the brush holder stay 21 side, and instead, on the end surface thereof, the peripheral wall 46 and the inner peripheral side of the peripheral wall 46 extend toward the center. A contact surface 47 is provided.

The motor 44 is also assembled in the same manner as the motor 1 described above. However, when the yoke 7 and the end bracket 11 are assembled, the outer peripheral portion of the peripheral wall 46 is fitted into a stay mounting groove 48 formed on the outer periphery of the end portion of the yoke 7. At this time, the bent portion 45 a of the stay pressing claw 45 abuts on the inner peripheral edge 46 a of the peripheral wall 46. The outer periphery of the bent portion 45a is a cylindrical surface, and this outer peripheral surface comes into contact with the inner peripheral edge 46a of the peripheral wall, that is, the inner corner of the peripheral wall 46. Further, the extended portion 45 b of the stay pressing claw 45 contacts the contact surface 47. By the abutment of the bent portion 45a, the peripheral wall 46, it is applied elastic holding force F ₃ having both components in the outer circumferential direction and the axial direction. Further, by abutment of the extended portion 45b, the contact surface 47, the elastic holding force F ₄ toward the axial direction is applied. As a result, force is applied to the brush holder stay 21 in the outer circumferential direction and the axial direction, and the brush holder stay 21 is fixed so as to be pressed against the yoke 7 and the end bracket 11.

  As described above, also in the motor 44 of the third embodiment, the brush holder stay 21 can be fixed in the yoke 7 without backlash without increasing the number of parts, similarly to the motor 1 of the first embodiment. Further, since the elastic region of the stay presser claw 45 can be set larger than the creep amount of the brush holder stay 21, even if creep deformation or the like occurs in the brush holder stay 21 itself, the holding force is maintained. It is possible to prevent the occurrence of mounting play.

It goes without saying that the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the scope of the invention.
For example, in the above-described embodiment, an example in which the motor according to the present invention is used as a driving source for a radiator cooling fan of an automobile has been shown. However, the present invention is applicable to a motor used in a high temperature atmosphere or a vibration environment. Further, in the above-described embodiment, an example in which two yoke insertion pieces 28 are provided in a projecting position is shown. However, at least one yoke insertion piece 28 is sufficient, and the number is not limited to two. However, since it is better to arrange the yoke insertion pieces 28 at the opposed positions, an even number such as 2, 4, 6 is preferably arranged symmetrically. Furthermore, the form of the stay presser claw 36 is not limited to the above-described example, and various shapes such as those without the hole 36b and those having a plurality of claws (for example, two) can be adopted. .

  In addition, in the motor 44 of the third embodiment, the stay pressing claw 45 is not necessarily in contact with both the peripheral wall 46 and the contact surface 47, but is in contact with either one to provide the elastic holding force to the brush holder stay 21. It only has to be added. However, it is preferable to contact both the peripheral wall 46 and the contact surface 47 because the elastic holding force is increased. Similarly to the first embodiment, the stay pressing claws 39 and 45 of the second and third embodiments may be provided with an elastic force adjusting hole (reference numeral 36b of the first embodiment).

Claims (9)

A stator including a cylindrical yoke, a plurality of magnets mounted in the yoke, and a magnet holder disposed between the magnets to hold the magnet in a predetermined position;
An armature fixed to a rotating shaft and rotatably disposed in the stator;
A commutator fixed to the rotating shaft and electrically connected to the armature;
A brush in sliding contact with the commutator;
A motor with a brush attached to the yoke and having a brush holder stay provided with a brush accommodating portion for accommodating and holding the brush;
The motor with a brush, wherein the magnet holder has a brush holder stay fixing portion that abuts the brush holder stay and can hold the brush holder stay in the motor.   The brushed motor according to claim 1, wherein the brush holder stay includes an extending portion that extends along an axial direction and is inserted into the yoke, and the brush holder stay fixing portion is in contact with the extending portion. The brushed motor, wherein the extending portion is clamped between the yoke inner peripheral surface.   3. The motor with brush according to claim 2, wherein the brush holder stay has a protrusion on the outer peripheral surface side of the extending portion that comes into contact with the inner peripheral surface of the yoke.   2. The motor with brush according to claim 1, wherein the brush holder stay includes an extending portion that extends along an axial direction and is inserted into the yoke, and the brush holder stay fixing portion is an outer peripheral surface of the extending portion. A motor with a brush, wherein the motor is in contact with the brush.   5. The motor with brush according to claim 2, wherein the brush holder stay has a flat portion on a side of the extended portion on which the brush holder stay fixing portion abuts.   6. The motor with brush according to claim 5, wherein the flat portion is arranged at a position corresponding to an advance angle setting of the motor.   2. The motor with brush according to claim 1, wherein the brush holder stay has a peripheral wall fitted to the inner peripheral portion of the yoke end surface, and a contact surface formed on the inner peripheral side of the peripheral wall and extending toward the center direction. The brush holder stay fixing portion is in contact with one or both of the peripheral wall and the contact surface.   The motor with a brush according to claim 1, wherein the brush holder stay fixing portion elastically contacts the brush holder stay.   9. The brush motor according to claim 8, wherein the brush holder stay fixing portion is formed in a cantilevered leaf spring shape and has an adjustment hole for adjusting an elastic force at the center thereof. With motor.

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