JP2020145902A - Motor with speed reducer - Google Patents

Abstract

To provide a motor with a speed reducer which can keep misalignment of an armature core small.SOLUTION: A motor 1 with a speed reducer according to the invention includes: a motor part 2; a case 14; and a cover. In the motor part, a rotary shaft 37 supported by a first bearing 22a and a second bearing 22b is rotatably housed in a yoke 5. Permanent magnets 40 are provided at the inner side of the yoke. The first bearing is press-fitted in a first bearing housing recessed part of the case, and the second bearing is inserted into a second bearing housing recessed part of the case. Movement of the first bearing in a first direction is restricted by a movement restriction part. The first bearing is pressed by a pressing part from a second direction. Each permanent magnet is disposed at a position which avoids a third direction.SELECTED DRAWING: Figure 3

Description

The present invention relates to a motor with a speed reducer.

As a motor with a speed reducer, a rotating shaft is provided in the bearing accommodating recess of the case via the first bearing and the second bearing, and the motor portion is connected to the end of the rotating shaft to decelerate at intervals with respect to the motor portion. It is known that the machine part is provided. The first bearing is provided at an intermediate portion between the motor portion and the speed reducer portion of the rotating shaft. Further, the second bearing is provided at a portion of the rotating shaft near the end opposite to the motor portion (see, for example, Patent Document 1).

Japanese Unexamined Patent Publication No. 2017-225289

Here, in order to provide the first bearing and the second bearing of the motor with a speed reducer of Patent Document 1 in the bearing accommodating recess, it is conceivable to press-fit the first bearing and the second bearing into the bearing accommodating recess. However, for example, when the first bearing is press-fitted into the bearing accommodating recess and the second bearing is press-fitted into the bearing accommodating recess, an unnecessarily large preload is applied from the second bearing to the rotating shaft, which causes a rotation loss. .. Therefore, the second bearing may be inserted into the bearing accommodating recess.
However, when the second bearing is inserted into the bearing accommodating recess, a gap is generated between the bearing and the bearing accommodating recess. Therefore, for example, the armature core of the motor portion is attracted by the magnet and moves by the gap, and the armature core may be largely displaced with the first bearing as a fulcrum.

Therefore, the present invention provides a motor with a speed reducer capable of suppressing the amount of shaft deviation of the armature core to be small.

In order to solve the above problems, in the motor with a speed reducer according to the present invention, the rotating shaft supported by the bearing is rotatably housed inside the yoke, and a plurality of magnets are provided in the radial direction inside the yoke. A case having a bearing accommodating recess for accommodating the bearing, and a cover covering the opening of the case are provided, and the axial direction of the rotating shaft is set to the first direction and the first direction. The direction in which the bearing is accommodated in the bearing accommodating recess is the second direction, the direction orthogonal to the first direction and the second direction is the third direction, and the bearing in the first direction is orthogonal to each other. A movement restricting portion for restricting movement and a pressing portion for pressing the bearing from the second direction are provided, and the magnet is arranged at a position avoiding the third direction.

The speed reducer-equipped motor according to the present invention includes at least a worm wheel that meshes with a worm formed on the rotation shaft and an output gear that transmits the rotation of the worm wheel and outputs a rotational force to the outside. A speed reducer portion to be accommodated is provided, and the bearing is provided between the speed reducer portion and the motor portion of the rotating shaft, and is press-fitted into the bearing accommodating recess in the movement restricting portion. The movement includes a first bearing to be regulated and a second bearing provided on the opposite side of the rotating shaft to the armature and pressed by the pressing portion in a state of being inserted into the bearing accommodating recess. The regulating portion is characterized in that it is composed of the bearing accommodating recess into which the first bearing is press-fitted.

In the motor with a speed reducer according to the present invention, the end face of the outer ring of the first bearing is press-fitted into the bearing accommodating recess, and the second bearing is characterized in that the outer ring is inserted into the bearing accommodating recess. And.

According to the present invention, the movement of the bearing in the first direction is regulated by the movement restricting portion, the bearing is pressed from the second direction by the pressing portion, and the magnet is arranged avoiding the third direction. As a result, the amount of misalignment of the armature core can be suppressed to a small size.

The perspective view which shows the appearance of the motor with a reduction gear of embodiment which concerns on this invention. The developed perspective view which shows the component structure of the motor with a speed reducer in embodiment. The perspective view which shows the state which broke the yoke of the motor with a reduction gear in embodiment. A cross-sectional view of the motor with a speed reducer of FIG. 3 as viewed from the axial direction. The plan view which shows the state which removed the cover from the motor with a speed reducer in embodiment. The plan view which enlarged the VI part of FIG. An enlarged plan view of part VII of FIG. The perspective view which shows the state which the case is removed from the motor with a speed reducer.

Next, the motor with a speed reducer according to the embodiment of the present invention will be described with reference to the drawings.

(Motor with reducer)
FIG. 1 is a perspective view showing the appearance of the motor 1 with a speed reducer. FIG. 2 is a developed perspective view showing a component configuration of the motor 1 with a speed reducer.
As shown in FIGS. 1 and 2, the motor 1 with a speed reducer is used, for example, in a power window device of a vehicle. The motor 1 with a speed reducer includes a motor unit 2 and a speed reduction mechanism 3 connected to the motor unit 2, and a clutch mechanism 4 is incorporated in the speed reduction mechanism 3.

(motor)
The motor unit 2 is a so-called brushed DC motor. The motor unit 2 includes a yoke 5 and an armature 6. The yoke 5 is formed in a bottomed tubular shape with a peripheral wall 5a and a bottom portion 5b (see FIG. 5), and an opening portion 5c is arranged toward the speed reduction mechanism 3. The armature shaft 7 is rotatably housed inside the yoke 5.

FIG. 3 is a perspective view showing a state in which the yoke 5 of the motor 1 with a speed reducer is broken. FIG. 4 is a cross-sectional view of the motor 1 with a speed reducer of FIG. 3 as viewed from the axial direction.
As shown in FIGS. 3 and 4, the peripheral wall 5a of the yoke 5 is an arcuate portion connecting eight flat portions 5d arranged at equal intervals in the circumferential direction and adjacent flat portions 5d in the circumferential direction. It is formed into a polygon by 5e.
A plurality of permanent magnets (magnets) 40 are provided in the radial direction on the inner surface of the flat portion 5d on the peripheral wall 5a of the yoke 5. In the embodiment, for example, an example in which eight permanent magnets 40 are provided will be described, but the number of permanent magnets 40 can be appropriately selected.
The permanent magnet 40 is formed flat so as to correspond to the inner surface of the flat portion 5d. Further, the eight permanent magnets 40 are arranged so that the magnetic poles of the N pole and the S pole alternate along the circumferential direction. An armature 6 is rotatably provided inside the yoke 5.

The armature 6 is externally fitted and fixed to the armature shaft 7, the armature core 8 which is externally fixed at a position corresponding to the permanent magnet 40 of the armature shaft 7, and the armature core 8 which is externally fitted and fixed to the speed reduction mechanism 3 side of the armature core 8. It is equipped with a commutator 9 (see FIG. 2).
The armature shaft 7 is coaxially integrated with the worm shaft 31 (see FIG. 2) described later. Hereinafter, the armature shaft 7 and the worm shaft 31 may be collectively referred to as a rotation shaft 37.

The armature core 8 is formed by stacking a plurality of core plates formed by pressing a metal plate or the like. By stacking a plurality of core plates, a plurality of dovetail-shaped slots S are formed between adjacent teeth T on the outer periphery of the armature core 8. An enamel-coated coil is wound around each slot S, whereby an armature coil C is formed on the outer periphery of the armature core 8.
In the embodiment, the plurality of slots S will be described as six, but the number of slots S can be appropriately selected. That is, in the embodiment, the motor unit 2 is composed of eight permanent magnets 40 and six slots S in eight poles and six slots.

As shown in FIG. 2, the terminal portion of the coil is connected to the commutator 9. The commutator 9 is formed in a substantially columnar shape. In the commutator 9, a plurality of conductive segments 9a are arranged side by side in the circumferential direction on the outer peripheral surface. A coil (not shown) is connected to these segments 9a.
Further, a brush (not shown) of the brush unit 10 is slidably contacted with the segment 9a. The brush unit 10 is electrically connected to an external power source (not shown) via the connector portion 11. Therefore, the current of the coil (not shown) is supplied through the brush 10a of the brush unit 10 and the segment 9a.

The connector portion 11 electrically connects an external power supply (not shown) and the brush unit 10. The connector portion 11 includes a frame portion 12 housed in a motor accommodating portion 16 described later of the speed reduction mechanism 3, and a connector receiving portion 13 integrally provided on one side of the frame portion 12.
A connector (not shown) extending from an external power source is fitted in the connector receiving portion 13. A terminal (not shown) of the connector receiving portion 13 is electrically connected to the brush unit 10.

The frame portion 12 is substantially rectangular and is formed in a frame shape. The opening 12a of the frame portion 12 communicates with the opening 5c of the yoke 5. Further, the opening 12a of the frame portion 12 is formed so that the commutator 9 can be inserted. The other end of the armature shaft 7 of the motor unit 2 projects toward the speed reduction mechanism 3 side through the opening 12a of the frame unit 12 and is connected to the speed reduction mechanism 3.

(Deceleration mechanism)
(Case)
FIG. 5 is a plan view showing a state in which the cover 15 is removed from the motor 1 with a speed reducer.
As shown in FIGS. 2 and 5, the speed reduction mechanism 3 is integrally formed with a substantially box-shaped case 14 having an opening 14a on one surface and the side of the motor portion 2 of the case 14, and is integrally molded with the opening 14a of the case 14. A motor accommodating portion 16 having a first opening 16a in the same direction, a cover 15 that closes the opening 14a of the case 14 and the first opening 16a of the motor accommodating portion 16, and a speed reducer housed in the case 14. A portion 30 and a clutch mechanism 4 housed in the case 14 are provided.

The motor portion 2 is attached to the motor accommodating portion 16, and the brush unit 10 and the connector portion 11 are accommodated. A second opening 16b is also formed on the side surface of the motor accommodating portion 16 to which the motor portion 2 is attached. The outer peripheral edge of the opening 5c of the yoke 5 is brought into contact with the outer peripheral edge of the second opening 16b. Then, at the contacted portion, the motor accommodating portion 16 and the yoke 5 are fastened and fixed by bolts (not shown).

Further, the second opening 16b of the motor accommodating portion 16 communicates with the first opening 16a. Then, the frame portion 12 of the connector portion 11 is inserted from the side of the first opening 16a of the motor accommodating portion 16, and the frame portion 12 is fitted to the inner peripheral edge of the second opening 16b to fit the motor accommodating portion 16 The connector portion 11 is housed in. Further, the brush unit 10 is inserted from the case 14 side of the connector portion 11 at the first opening portion 16a of the motor accommodating portion 16. As a result, the brush unit 10 is accommodated on the case 14 side of the connector portion 11 of the motor accommodating portion 16.

The case 14 is made of, for example, an aluminum material. The case 14 includes a worm shaft accommodating recess 17 formed along the axis of the armature shaft 7 of the motor portion 2, a worm wheel accommodating recess 18 arranged on both sides of the worm shaft accommodating recess 17, and a drive gear accommodating recess. The recess 19 and the clutch accommodating recess 20 formed on the bottom surface (base surface) 18a of the worm wheel accommodating recess 18 are provided.
The worm shaft accommodating recess 17 is formed to extend so as to penetrate the side wall 14b of the case 14. Bearing accommodating recesses 21a and 21b (first bearing accommodating recesses 21a, second bearings) opened in the side wall 14b of the case 14 in the same direction as the opening 14a of the case 14 at a place where the worm shaft accommodating recess 17 is penetrated. The accommodating recess 21b) is formed.

FIG. 6 is an enlarged plan view of the VI portion of FIG.
As shown in FIGS. 5 and 6, the rotating shaft 37 is accommodated in the first bearing accommodating recess 21a and the second bearing accommodating recess 21b via the first bearing (bearing) 22a and the second bearing (bearing) 22b.
Hereinafter, the axial direction of the rotating shaft 37 is referred to as the first direction X. Further, the direction orthogonal to the first direction X and the direction in which the first bearing 22a and the second bearing 22b are accommodated in the first bearing accommodating recess 21a and the second bearing accommodating recess 21b is defined as the second direction Z. Further, the direction orthogonal to the first direction X and the second direction Z is defined as the third direction Y.

Of the bearing accommodating recesses 21a and 21b, the first bearing 22a that rotatably supports the other end 7b of the armature shaft 7 is press-fitted into the first bearing accommodating recess 21a (see FIG. 2) on the motor accommodating portion 16 side. It is contained. A movement restricting portion 21c1 for restricting the movement of the first bearing 22a in the first direction X is formed on the wall surface 21c of the first bearing accommodating recess 21a. In other words, the first bearing 22a is provided at an intermediate portion 37a (that is, the other end 7b of the armature shaft 7) between the speed reducer portion 30 and the motor portion 2 of the rotating shaft 37. As the first bearing 22a, for example, a ball bearing is used.
Specifically, in the first bearing 22a, both end faces (end faces) 22d and 22e of the first outer ring 22c are press-fitted into the wall surface 21d of the first bearing accommodating recess 21a and the movement restricting portion 21c1. Further, in the first bearing 22a, the outer peripheral surface 22f of the first outer ring 22c is inserted into the inner peripheral surface 21e of the first bearing accommodating recess 21a.
Here, press-fitting means that the press-fitting allowance between the end surface 22d of the first outer ring 22c, the movement restricting portion 21c1, the wall surface 21d of the first bearing accommodating recess 21a, and the movement restricting portion 21c1 is, for example, 0.001 to 0.009 mm. The set state.

The reasons for press-fitting both end faces 22d and 22e of the first outer ring 22c into the first bearing accommodating recess 21a are as follows.
That is, when fixing the first bearing 22a to the first bearing accommodating recess 21a of the case 14, it may not be preferable to press-fit the first bearing 22a into the first bearing accommodating recess 21a in the radial direction. For example, when the case 14 is made of an aluminum material, when the first bearing 22a is press-fitted into the first bearing accommodating recess 21a within the tolerance of the first bearing 22a and the first bearing accommodating recess 21a, the first bearing 22a Is considered to be in a state of strong press-fitting. When the first bearing 22a is strongly press-fitted, the first bearing 22a is crushed in the radial direction, which causes an abnormal noise.

Therefore, of the first bearing 22a, both end faces 22d and 22e of the first outer ring 22c are press-fitted into the wall surface 21d of the first bearing accommodating recess 21a and the movement restricting portion 21c1. In a state where both end faces 22d and 22e of the first outer ring 22c are press-fitted into the wall surface 21d and the movement restricting portion 21c1, a pressing force in the thrust direction acts on the first outer ring 22c of the first bearing 22a. As a result, it is possible to suppress the first outer ring 22c from being crushed in the radial direction and suppress the generation of abnormal noise.

In this way, the first bearing 22a is provided at the intermediate portion 37a of the rotating shaft 37, and both end faces 22d and 22e of the first outer ring 22c are press-fitted into the wall surface 21d of the first bearing accommodating recess 21a and the movement restricting portion 21c1. There is. That is, the movement of the first bearing 22a in the first direction X is regulated by the movement regulating unit 42.
As described above, by configuring the movement restricting portion 42 by utilizing the wall surface 21d of the first bearing accommodating recess 21a and the movement restricting portion 21c1, the movement restricting portion 42 can be provided without increasing the number of parts.
Further, both end surfaces 22d and 22e of the first outer ring 22c are press-fitted into the wall surface 21d of the first bearing accommodating recess 21a and the movement restricting portion 21c1, so that the second direction Z and the third direction Y of the first bearing 22a are press-fitted. The movement to the first bearing accommodating recess 21a can be suppressed.

FIG. 7 is an enlarged plan view of part VII of FIG.
As shown in FIGS. 2 and 7, of the bearing accommodating recesses 21a and 21b, the second bearing accommodating recess 21b on the side opposite to the motor accommodating portion 16 has an end portion 31a of the worm shaft 31 described later (in FIG. 2). A second bearing 22b that rotatably supports the left end) is inserted and accommodated. In other words, the second bearing 22b is provided at the end portion 37b of the rotating shaft 37 on the opposite side of the armature 6 (that is, the end portion 31a of the worm shaft 31). In the second bearing 22b, for example, the second outer ring 22g is inserted and accommodated in the second bearing accommodating recess 21b. As the second bearing 22b, for example, a ball bearing is used.

Specifically, in the second bearing 22b, both end faces (end faces) 22h and 22i of the second outer ring 22g are inserted into the second bearing accommodating recess 21b. Further, in the second bearing 22b, the outer peripheral surface 22j of the second outer ring 22g is inserted into the inner peripheral surface 21f of the second bearing accommodating recess 21b.
By inserting the second bearing 22b into the second bearing accommodating recess 21b, a gap can be secured between the second bearing 22b and the second bearing accommodating recess 21b. Therefore, it is possible to suppress the action of a relatively large pressing force from the second bearing accommodating recess 21b to the second bearing 22b. As a result, it is possible to suppress an unnecessarily large preload from acting on the rotating shaft 37 from the second bearing 22b, and it is possible to suppress the occurrence of rotational loss.

Further, by inserting the second bearing 22b into the second bearing accommodating recess 21b, a gap is generated between the second bearing 22b and the second bearing accommodating recess 21b so that the second bearing 22b moves in the third direction Y. It is conceivable to do.
Here, in the first bearing 22a and the second bearing 22b, for example, the inner ring is press-fitted into the rotating shaft 37. Therefore, by restricting the movement of the first bearing 22a in the first direction X by the movement restricting unit 42, the movement of the second bearing 22b in the first direction X can be regulated.

As shown in FIGS. 2 and 5, a drive support shaft 23 for rotatably supporting the drive gear 35, which will be described later, is erected on the bottom 19a of the drive gear accommodating recess 19.
Further, a substantially cylindrical bearing portion 25 is integrally formed on the bottom portion 20a of the clutch accommodating recess 20. The base end of the worm support shaft 24 for rotatably supporting the worm wheel 32, which will be described later, is press-fitted into the bearing portion 25.

The axial direction of the drive support shaft 23 and the worm support shaft 24 is orthogonal to the axial direction of the rotation shaft 37. A flange portion 24a is formed at the base end of the worm support shaft 24. On the other hand, a male screw portion 24b is engraved on the tip (the other end) of the worm support shaft 24. The male screw portion 24b is used to prevent the speed reducer portion 30 and the clutch mechanism 4 rotatably supported by the worm support shaft 24 from coming off.

Under such a configuration, the tip of the worm support shaft 24 is press-fitted into the bearing portion 25 from the outside of the bottom portion 20a of the clutch accommodating recess 20 (outside the bottom portion of the case 14). By bringing the flange portion 24a into contact with the bottom portion 20a of the clutch accommodating recess 20, positioning of the worm support shaft 24 with respect to the clutch accommodating recess 20 is performed. As a result, the worm support shaft 24 protrudes from the bottom 20a of the clutch accommodating recess 20.

In addition, on the outer surface of the case 14, three bolt seats 27 for attaching the case 14 to the vehicle body or the like are formed at substantially equal intervals in the circumferential direction. Each bolt seat 27 is formed with an insertion hole 27a into which a bolt (not shown) can be inserted.
Further, a plurality of female screw seats 81 are formed on the outer surface of the case 14. The female screw seat 81 is for fastening and fixing the cover 15 to the case 14.
Further, a step portion 29 into which the cover 15 is fitted is formed on the inner peripheral edge of the opening 14a of the case 14.

(Reducer section)
The speed reducer unit 30 is integrally formed with the armature shaft 7 protruding from the motor unit 2, and is meshed with the worm shaft 31 housed in the worm shaft housing recess 17 and the worm of the worm shaft 31 to form the worm wheel housing recess 18. The worm wheel 32 to be accommodated, the pinion gear 33 arranged at the upper portion of the worm wheel 32 opposite to the clutch accommodating recess 20 and integrated with the clutch mechanism 4, the spur gear 34 meshed with the pinion gear 33, and the spur gear. It includes a drive gear (output gear) 35 integrated with 34, and a nut 46. Therefore, the rotation of the worm wheel 32 is transmitted to the drive gear 35.

The worm shaft 31 extends coaxially with the armature shaft 7. The end 31a of the worm shaft 31 opposite to the armature shaft 7 (that is, the end 37b of the rotating shaft 37 opposite to the armature 6) is the second bearing inserted into the bearing accommodating recess 21b of the case 14. It is rotatably supported by 22b.

(cover)
FIG. 8 is a perspective view showing a state in which the case 14 is removed from the motor 1 with a speed reducer.
As shown in FIGS. 2 and 8, the cover 15 is formed of a resin material in a substantially plate shape. The cover 15 is integrally formed with a cover main body 61 that closes (covers) the opening 14a of the case 14, and a motor-side cover 62 that closes the first opening 16a of the motor housing portion 16.
A mounting seat 82 is formed on the outer peripheral portion of the cover 15 at a position corresponding to the female screw seat 81 of the case 14. The mounting seat 82 is formed with an insertion hole 82a through which the bolt 80 can be inserted. A bolt 80 is inserted into the insertion hole 82a from the side opposite to the case 14, and the bolt 80 is screwed into the case 14. As a result, the cover 15 is fastened and fixed to the case 14.

The motor side cover 62 is formed in a substantially C-shaped cross section so that the side of the motor accommodating portion 16 opens. The motor side cover 62 is formed so as to project from the cover 15 toward the side opposite to the case 14. A plurality of (three in this embodiment) ribs 66 straddling the side wall 62a and the cover body 61 are integrally formed between the side wall 62a of the motor side cover 62 and the cover body 61. The rib 66 is for increasing the mechanical strength of the cover 15 and suppressing vibration (resonance avoidance).

Further, the cover body 61 is formed with an opening 67 through which the drive body 53 of the drive gear (output gear) 35 and the seal wall 56 can be inserted. A part of the base portion 52 and the drive main body 53 are exposed to the outside through the opening 67. Therefore, the rotation of the worm wheel 32 is transmitted to the drive gear 35, and the rotational force is output from the drive gear 35 to the outside.
Further, the cover body 61 is provided with a seal portion 68 for sealing between the opening 67 and the seal wall 56 on the peripheral edge of the opening 67. The seal portion 68 is formed of, for example, rubber or the like.

A bearing boss 65 projecting toward the side opposite to the case 14 is integrally formed on the cover body 61 at a position corresponding to the worm support shaft 24 erected in the worm wheel accommodating recess 18. The bearing boss 65 is formed in a substantially bottomed cylindrical shape so that the case 14 side opens. The tip of the worm support shaft 24 is supported on the cover body 61 by the cover 15 fixed to the case 14 via a bearing boss 65 or the like.

As shown in FIGS. 5 and 8, in the cover main body 61, the first pressing portion (pressing portion) 54 and the second pressing portion (pressing portion) 54 and the second pressing portion (pressing portion) 54 and the second pressing portion (pressing portion) 54 and the second The pressing portion (pressing portion) 55 is fixed. The first pressing portion 54 and the second pressing portion 55 are elastic members formed of an elastomer or the like.
The first pressing portion 54 may press the portion of the first bearing 22a housed in the first bearing accommodating recess 21a by press fitting, which is exposed from the opening of the first bearing accommodating recess 21a, from the second direction Z. it can. Therefore, the movement of the first bearing 22a in the second direction Z can be further suppressed by the first pressing portion 54.

The second pressing portion 55 may press the portion of the second bearing 22b that is inserted into the second bearing accommodating recess 21b and is exposed from the opening of the second bearing accommodating recess 21b from the second direction Z. it can. Therefore, the movement of the second bearing 22b in the second direction Z can be suppressed by the first pressing portion 54.
Here, by using the second pressing portion 55 as an elastic member, it is possible to prevent the second bearing 22b from being strongly pressed by the second pressing portion 55 with an excessive pressing force. As a result, it is possible to suppress an unnecessarily large preload from acting on the rotating shaft 37 from the second bearing 22b, and it is possible to suppress the occurrence of rotational loss.
Further, the second pressing portion 55 is accommodated by being inserted into the second bearing accommodating recess 21b. Therefore, in a state where the second bearing 22b is pressed by the second pressing portion 55, a gap is generated between the second bearing 22b and the second bearing accommodating recess 21b so that the second bearing 22b moves in the third direction Y. To do.

By the way, both end faces 22d and 22e of the first outer ring 22c are press-fitted into the wall surface 21d of the first bearing accommodating recess 21a and the movement restricting portion 21c1. As a result, the movement of the first bearing 22a in the first direction X, the second direction Z, and the third direction Y is regulated by the first bearing accommodating recess 21a (movement regulating portion 42).
In addition, the movement regulation unit 42 regulates the movement of the second bearing 22b in the first direction X. Further, the movement of the second bearing 22b in the second direction Z is suppressed by the first pressing portion 54. Further, a gap is generated between the second bearing 22b and the second bearing accommodating recess 21b so that the second bearing 22b moves in the third direction Y.

Therefore, the second bearing 22b (that is, the rotating shaft 37) may be displaced in the third direction Y. Therefore, when the permanent magnet 40 (see FIG. 4) is arranged at the position in the third direction Y, the armature core 8 provided on the rotating shaft 37 is attracted by the permanent magnet 40 in the third direction Y. As a result, it is conceivable that the armature core 8 moves with the first bearing 22a as a fulcrum due to the attractive force of the permanent magnet 40, and the axis shift occurs.
Therefore, the permanent magnet 40 (see FIG. 4) is arranged at a position avoiding (removing) the third direction Y.

That is, as shown in FIGS. 3 and 4, in the yoke 5, the arcuate portion 5e of the peripheral wall 5a is arranged in the third direction Y. Further, the permanent magnet 40 is arranged on the flat portion 5d of the peripheral wall 5a. Therefore, the permanent magnets 40 are arranged at intervals of predetermined angles θ (for example, 22.5 °) in the circumferential direction with respect to the third direction Y. Therefore, the permanent magnet 40 is arranged at a position avoiding the third direction Y. As a result, the attractive force of the armature core 8 provided on the rotating shaft 37 attracted by the permanent magnet 40 in the third direction Y can be suppressed to a small value. That is, the amount of axial deviation of the armature core 8 in the third direction Y can be suppressed to a small value.
As a result, the amount of axial deviation of the armature core 8 in the first direction X, the second direction Z, and the third direction Y can be suppressed to be small, the vibration of the armature core 8 can be reduced, and the operating noise can be suppressed.

The present invention is not limited to the above-described embodiment, and includes various modifications of the above-described embodiment without departing from the spirit of the present invention.
For example, in the above-described embodiment, the configuration of the motor unit 2 having eight permanent magnets 40 and six slots S for eight poles and six slots has been described, but the number of slots and the number of poles are not limited to eight poles and six slots.

Further, in the above-described embodiment, an example in which the peripheral wall 5a of the yoke 5 is formed into a polygon by eight flat portions 5d and an arc-shaped portion 5e connecting the flat portions 5d has been described, but the present invention is not limited to this. As another example, for example, the yoke may have a cylindrical shape, a magnet cylindrical shape, or a magnet segment shape.

1 Motor with reducer 2 Motor part 5 York 6 Armature 7 Armature shaft 14 Case 14a Opening 15 Cover 21a 1st bearing accommodating recess (bearing accommodating recess)
21b 2nd bearing accommodating recess (bearing accommodating recess)
22a 1st bearing (bearing)
22b 2nd bearing (bearing)
22c 1st outer ring 22g 2nd outer ring 22d, 22e Both end faces (end faces) of the 1st outer ring
22h, 22i Both end faces (end faces) of the second outer ring
30 Reducer section 30
31 Warm axis (warm)
32 Warm wheel 35 Drive gear (output gear)
37 Rotating shaft 40 Permanent magnet (magnet)
42 Movement regulation part 54 First pressing part (pressing part)
55 Second pressing part (pressing part)
X 1st direction X
Y 3rd direction Y
Z 2nd direction Z

Claims (3)

A motor unit in which a rotating shaft supported by a bearing is rotatably housed inside the yoke and a plurality of magnets are provided in the radial direction inside the yoke.
A case in which a bearing accommodating recess for accommodating the bearing is formed, and
A cover that covers the opening of the case is provided.
The axial direction of the rotating shaft is the first direction, the direction orthogonal to the first direction, and the direction in which the bearing is accommodated in the bearing accommodating recess is orthogonal to the second direction, the first direction, and the second direction. The direction to do is the third direction
A movement control unit that regulates the movement of the bearing in the first direction,
A pressing portion that presses the bearing from the second direction is provided.
A motor with a speed reducer, characterized in that the magnet is arranged at a position avoiding the third direction. A speed reducer unit including at least a worm wheel that meshes with a worm formed on the rotation shaft and an output gear that transmits the rotation of the worm wheel and outputs a rotational force to the outside, and is housed in the case.
The bearing is
A first bearing, which is provided between the speed reducer portion and the motor portion of the rotating shaft and is regulated by the movement restricting portion by being press-fitted into the bearing accommodating recess.
A second bearing, which is provided on the opposite side of the armature of the rotating shaft and is pressed by the pressing portion in a state of being inserted into the bearing accommodating recess, is provided.
The movement restricting portion is composed of the bearing accommodating recess into which the first bearing is press-fitted.
The motor with a speed reducer according to claim 1. In the first bearing, the end face of the outer ring is press-fitted into the bearing accommodating recess.
The motor with a speed reducer according to claim 2, wherein the second bearing has an outer ring inserted into the bearing accommodating recess.

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