JP7275437B2 - motor - Google Patents

Description

The present invention relates to motors.

Conventionally, some motors hold bearings using a fixed member such as a housing and a ring. For example, Patent Literatures 1 and 2 disclose a configuration in which a bearing that rotatably supports a rotor of a motor is sandwiched between a housing and a ring member on both sides in the axial direction. In this configuration, the ring member is bolted to the housing to hold down the bearing.

JP-A-4-197057 JP-A-9-331646

In the motor as described above, when the ball screw or the like is driven, when the rotor is rotated, the ball screw operates along the axial direction of the rotor and the ball screw. When the ball screw operates in the axial direction, an axial reaction force acts on the rotor via the ball screw from the object driven by the ball screw. When the ring member is axially pushed through the rotor by this reaction force or an external force applied from the outside, the bolts fixing the ring member to the housing may loosen. As a result, an axial gap is generated between the bearing and the housing and the ring member, causing the bearing and rotor to move axially during operation of the motor. In order to firmly fix the ring member, the axial force of the bolt should be increased, but this requires increasing the strength of the housing, for example, by increasing the thickness of the housing to which the bolt is fastened. As a result, there is a problem that the size of the housing is increased, the cost is increased, and the like.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a motor capable of suppressing loosening of a member holding a bearing and suppressing rattling of the bearing while suppressing an increase in the size and cost of the housing. one of the purposes.

One aspect of the motor of the present invention is a cylindrical housing having an opening at one end in the axial direction and a female screw portion on the inner peripheral surface of the opening; a stator provided radially inward of the stator and to which a member to be driven is connected; a bearing supported by the housing and supporting the rotor rotatably around the central axis of the rotor; a bearing holding portion extending radially inward from the housing and abutting against the bearing from the other side in the axial direction; and a male screw provided in the opening of the housing and fastened to the female screw portion on an outer peripheral surface a pressing member for pressing the bearing toward the other side in the axial direction; and a rotation restricting portion for restricting rotation of the pressing member inside the opening, wherein the rotation restricting portion comprises at least one crimped portion provided so as to straddle the boundary between the outer peripheral edge of the pressing member and the inner peripheral edge of the opening on one end face in the axial direction of the housing.
Another aspect of the motor of the present invention is a cylindrical housing having an opening at one end in the axial direction and a female screw portion on the inner peripheral surface of the opening; a stator provided in the stator, a rotor provided radially inside the stator to which a driven member is connected, and a bearing supported by the housing and supporting the rotor rotatably around the central axis of the rotor. a bearing holding portion extending radially inward from the housing and abutting against the bearing from the other side in the axial direction; a pressing member having a male screw portion and pressing the bearing toward the other side in the axial direction; and a rotation restricting portion that restricts rotation of the pressing member inside the opening, The restraining portion is composed of at least one welded portion provided so as to straddle a boundary portion between the outer peripheral edge of the pressing member and the inner peripheral edge of the opening on one axial end face of the housing.

According to the exemplary motor of the present invention, it is possible to suppress loosening of the member that presses the bearing and suppress rattling of the bearing while suppressing an increase in housing size and cost.

FIG. 1 is a cross-sectional view of a motor in one exemplary embodiment. FIG. 2 is a perspective view showing the appearance of the motor of one exemplary embodiment. FIG. 3 is a perspective view showing a state in which the pressing member of the motor of the exemplary embodiment is removed from the housing. FIG. 4 is a cross-sectional view showing the configuration of the essential parts of the motor of one exemplary embodiment. FIG. 5 is a perspective view showing the appearance of a motor in a modification of an exemplary embodiment; FIG. 6 is a cross-sectional view showing the configuration of the essential parts of the motor in another modification of the exemplary embodiment.

FIG. 1 is a cross-sectional view of a motor of one embodiment. FIG. 2 is a perspective view showing the appearance of the motor of this embodiment. FIG. 3 is a perspective view showing a state in which the pressing member of the motor of this embodiment is removed from the housing. FIG. 4 is a cross-sectional view showing the configuration of the essential parts of the motor of this embodiment.

As shown in FIG. 1 , the motor 10 includes a housing 11 , a stator 20 , a rotor 30 , a bearing 35 , a flange portion (bearing holding portion) 14 and a pressing member 40 .

The housing 11 includes a tubular portion 11a having a cylindrical shape, and one axial end (the right side in FIG. 1) of the tubular portion 11a along the central axis J of the tubular portion 11a. and an extending end plate portion 11b. The other (left in FIG. 1) end portion 11c in the axial direction of the cylindrical portion 11a of the housing 11 is connected to a device or the like to be driven by the motor 10 . An end portion 11c of the cylindrical portion 11a opens toward the device including the member 100 to be driven. As shown in FIG. 2, the end portion 11c of the cylindrical portion 11a is provided with a connection flange portion 13 extending radially outward with respect to the central axis J for connecting the housing 11 to a device or the like to be driven. .

The flange portion 14 extends radially inward from the inner peripheral surface of the cylindrical portion 11 a of the housing 11 . The flange portion 14 is arranged on the other side in the axial direction with respect to the bearing 35 which will be described later. The flange portion 14 may be continuous in the circumferential direction around the central axis J, or may be intermittently provided partially in the circumferential direction.

As shown in FIG. 3, the housing 11 has an opening 12 provided in the central portion of the end plate portion 11b. A female screw portion 15 is provided on the inner peripheral surface of the opening 12 .

As shown in FIG. 1 , the stator 20 is provided inside the tubular portion 11 a of the housing 11 . The stator 20 is located radially outside the center axis J of the rotor 30 . The stator 20 mainly includes a stator core 21 , tooth portions 22 and coils 23 .

The stator core 21 is provided on the inner peripheral surface of the cylindrical portion 11a. The stator core 21 is configured in a cylindrical shape as a whole by laminating a plurality of annular steel plates in the axial direction. Teeth portion 22 is provided radially inward of stator core 21 .

The tooth portion 22 has a plurality of teeth 22a provided at equal intervals in the circumferential direction around the central axis J. As shown in FIG. The coil 23 is wound around the tooth 22a via an insulating member such as resin.

A bus bar 24 electrically connected to the plurality of coils 23 is provided on the end portion 11 c side of the cylindrical portion 11 a of the housing 11 . The bus bar 24 is provided with connection terminals 25 extending outside the housing 11 . For example, three sets of bus bars 24 and connection terminals 25 are provided for each phase of the stator 20 . Wiring (not shown) for supplying power to the motor 10 from the outside is connected to each connection terminal 25 .

The rotor 30 is provided radially inside the stator 20 . The rotor 30 includes a rotor body 31 , permanent magnets 32 and a rotor cover 33 .

The rotor main body 31 includes a tubular body 31a extending in the axial direction, an end plate 31b extending radially inward from the tubular portion 11a at one axial end of the tubular body 31a, and an end plate 31b. and a cylindrical boss portion 31c that is provided in the central portion of and protrudes to one side in the axial direction. The rotor body 31 has a connection recess 31s that opens toward the other side in the axial direction. A driven member 100 that is rotationally driven by the motor 10 is connected to the connection recess 31s.

A cylindrical yoke 34 is provided at the other axial end of the cylindrical body 31a.

A plurality of permanent magnets 32 are provided at equal intervals in the circumferential direction around the central axis J on the outer peripheral surface of the cylindrical body 31a. The rotor cover 33 has a cylindrical shape and is provided so as to cover the cylindrical body 31a of the rotor body 31 and the plurality of permanent magnets 32 from the radially outer side. Note that the permanent magnet 32 may be annular. Moreover, when the rotor body 31 is a laminated steel plate, the plurality of permanent magnets 32 may be embedded in the rotor body 31 .

The bearing 35 is provided radially outside the boss portion 31 c of the rotor body 31 . The bearing 35 is a ball bearing and includes an annular outer ring 35a, an annular inner ring 35b provided radially inside the outer ring 35a, and a plurality of balls 35c provided between the outer ring 35a and the inner ring 35b. , provided. The inner ring 35 b of the bearing 35 is fitted to the outer peripheral surface of the boss portion 31 c of the rotor 30 . The outer ring 35a of the bearing 35 is fixed to the housing 11 by being sandwiched from both sides in the axial direction by the flange portion 14 and the pressing member 40, which will be described later. Thereby, the bearing 35 supports the rotor 30 rotatably around the central axis J. As shown in FIG. The bearing 35 is made of, for example, a bearing steel material (iron-based alloy).

As shown in FIGS. 3 and 4, the opening 12 of the housing 11 is provided with a concave portion 16 that is recessed on the other side in the axial direction. A bearing 35 is housed within the recess 16 . Thereby, the flange portion 14 is arranged on the other side in the axial direction with respect to the bearing 35 in the recess portion 16 . The flange portion 14 abuts against the outer ring 35a of the bearing 35 from the other side in the axial direction.

A pressing member 40 is provided in the opening 12 of the housing 11 . The pressing member 40 has a tool insertion hole 42 for a tool (not shown) for rotating the pressing member 40 around the central axis J at the center. The pressing member 40 has a male threaded portion 45 fastened to the female threaded portion 15 on its outer peripheral surface. As shown in FIG. 4, the pressing member 40 is attached to the opening 12 by fastening the male threaded portion 45 to the female threaded portion 15, and presses the bearing 35 toward the other side in the axial direction. As a result, the bearing 35 is sandwiched from both sides in the axial direction by the pressing member 40 provided on one side in the axial direction and the flange portion 14 provided on the other side in the axial direction.

The outer diameter of the pressing member 40 is larger than the outer diameter of the bearing 35 . Also, the inner diameter of the tool insertion hole 42 of the pressing member 40 is smaller than the inner diameter of the outer ring 35 a of the bearing 35 . As a result, the pressing member 40 abuts against the outer ring 35a of the bearing 35 from one side in the axial direction. Also, the inner diameter of the female threaded portion 15 of the opening 12 and the outer diameter of the male threaded portion 45 of the pressing member 40 are larger than the inner diameter of the flange portion 14 .

The rotation restricting portion 50</b>A restricts the pressing member 40 from rotating inside the opening 12 and loosening the male screw portion 45 from the female screw portion 15 . The rotation restricting portion 50A is composed of at least one crimped portion 51 . The crimped portion 51 is provided at the boundary between the outer peripheral edge of the pressing member 40 and the inner peripheral edge of the opening 12 . In the present embodiment, the crimped portions 51 are provided at four locations equidistantly in the circumferential direction on the boundary between the outer peripheral edge of the pressing member 40 and the inner peripheral edge of the opening 12 . Each caulked portion 51 is provided by, for example, applying a tool such as a punch so as to straddle the outer peripheral edge of the pressing member 40 and the inner peripheral edge of the opening 12 and hitting them with a hammer, press machine, or the like.

The caulked portion 51 has a convex portion 51a and a concave portion 51b. The convex portion 51 a is provided on the outer peripheral edge of the pressing member 40 . The convex portion 51 a radially protrudes toward the other inner peripheral edge of the opening 12 . The recess 51 b is provided on the inner peripheral edge of the opening 12 . The concave portion 51 b is recessed toward the outer peripheral edge of the pressing member 40 . At least part of the protrusion 51a is accommodated in the recess 51b. In this manner, the pressing member 40 is restrained from rotating inside the opening 12 by accommodating the protrusion 51a on the pressing member 40 side in the recessed portion 51b on the opening 12 side. The caulked portion 51 may be provided with a concave portion 51b on the pressing member 40 side and a convex portion 51a on the opening 12 side.

In this embodiment, the housing 11 and the pressing member 40 are each made of an aluminum alloy. Thereby, the coefficient of linear expansion of the material of the housing 11 becomes close to the coefficient of linear expansion of the material of the pressing member 40 . Therefore, it is possible to suppress loosening of the pressing member 40 due to thermal expansion and thermal contraction.

The surface of the pressing member 40 is provided with a coating 61 made of a material harder than the material (aluminum alloy) of the base material forming the pressing member 40 . The coating 61 may be provided at least on a portion of the pressing member 40 that abuts against the bearing 35 in the axial direction. Further, the coating 61 may be provided on at least the entire surface of the pressing member 40 that abuts against the bearing 35 in the axial direction. The coating 61 may cover the entire surface of the pressing member 40 . As such a film 61, for example, an aluminum oxide film formed by alumite treatment is suitable. Alternatively, DLC (diamond-like carbon) may be used as the film 61 . Such coating 61 preferably has a lower coefficient of friction than the base material (aluminum alloy) forming pressing member 40 .

A sealing member 70 is provided between the female threaded portion 15 of the housing 11 and the male threaded portion 45 of the pressing member 40 . An anaerobic resin, a sealant (adhesive), or the like is suitable for the sealing material 70 .

Such a motor 10 is supplied with electric current through connection terminals 25 from an external generator or the like. The supplied current is supplied to the coil 23 via the busbar 24, and the coil 23 generates a magnetic field (alternating magnetic field). The rotor main body 31 of the rotor 30 is rotationally driven around the central axis J by interaction between the magnetic field generated by the coil 23 and the magnetic field of the permanent magnet 32 of the rotor 30 .

As shown in FIG. 1 , a driven member 100 is connected to a rotor body 31 of the motor 10 . In this embodiment, the end of a ball screw 101 is connected to the rotor body 31 as the driven member 100 . The ball screw 101 is provided with a spiral groove 101a on its outer peripheral surface. A slide member 102 is provided radially outside the ball screw 101 . The slide member 102 is cylindrical and has a spiral groove 102a on its inner peripheral surface. A plurality of balls 103 are interposed in the spiral space between the groove 101 a of the ball screw 101 and the groove 102 a of the slide member 102 . When the ball screw 101 is rotationally driven around the central axis J by the motor 10, the slide member 102 slides along the axial direction. By sliding the slide member 102, the driven member 100 exerts a driving force along the axial direction.

As described above, when the slide member 102 slides in the axial direction and exerts a driving force along the axial direction, the reaction force from the object to be driven is input to the slide member 102 . Axial reaction force input to the slide member 102 is transmitted to the bearing 35 via the balls 103 , the ball screw 101 and the rotor body 31 . For example, when the slide member 102 slides away from the rotor body 31 along the central axis J, the reaction force F1 presses the bearing 35 toward the pressing member 40 . Further, when the slide member 102 slides from the rotor body 31 along the central axis J in a direction approaching the rotor body 31, the reaction force F2 presses the bearing 35 toward the flange portion 14 side.

Even if the pressing member 40 is repeatedly pressed by the bearing 35 due to the reaction force F1, the loosening of the pressing member 40 from the opening 12 is suppressed by the rotation restricting portion 50A composed of the crimped portion 51.例文帳に追加In addition, the sealing member 70 provided between the female threaded portion 15 of the housing 11 and the male threaded portion 45 of the pressing member 40 prevents loosening of the pressing member 40 due to repeated pressing of the bearing 35 by the reaction force F1. occurrence is suppressed.

In addition, the coating 61 provided on the pressing member 40 suppresses wear of the pressing member 40 due to repeated pressing by the bearing 35 due to the reaction force F1. In addition, since the coating 61 reduces the coefficient of friction between the pressing member 40 and the bearing 35, wear due to pressing of the bearing 35 is suppressed.

According to the present embodiment, the motor 10 includes a holding member 40 having a male screw portion 45 that is fastened to the female screw portion 15 on the outer peripheral surface thereof, and the holding member 40 is restrained from rotating inside the opening 12. and a rotation restricting portion 50A. As a result, it is possible to suppress loosening of the pressing member 40 in a direction away from the bearing 35 in the axial direction. Accordingly, loosening of the pressing member 40 can be prevented without increasing the tightening force (axial force) of the pressing member 40 to prevent loosening. As a result, the need to increase the strength of the opening 12 (housing 11) provided with the female threaded portion 15 to which the male threaded portion 45 of the pressing member 40 is fastened can be suppressed, and the increase in size and cost of the housing 11 can be suppressed. can be done. As a result, it is possible to suppress loosening of the pressing member 40 that presses the bearing 35 and to suppress rattling of the bearing 35 while suppressing an increase in the size and cost of the housing 11 .

According to the present embodiment, at least one crimped portion 51 provided at the boundary between the outer peripheral edge of the pressing member 40 and the inner peripheral edge of the opening 12 restrains the pressing member 40 from rotating inside the opening 12 . be done. As a result, it is possible to suppress loosening of the pressing member 40 in a direction away from the bearing 35 in the axial direction.

According to the present embodiment, the crimped portion 51 is provided on the outer peripheral edge of the pressing member 40 and protrudes radially toward the inner peripheral edge of the opening 12 , and the crimped portion 51 is provided on the inner peripheral edge of the opening 12 and presses. and a concave portion 51b that is recessed toward the outer peripheral edge of the member 40 and accommodates the convex portion 51a. As a result, a crimped portion 51 is provided at the boundary between the outer peripheral edge of the pressing member 40 and the inner peripheral edge of the opening 12 , and the loosening of the pressing member 40 in the direction away from the bearing 35 in the axial direction can be suppressed.

According to this embodiment, the housing 11 and the pressing member 40 are made of an aluminum alloy, and the bearing 35 is made of a ferrous alloy. Thus, when the pressing member 40 is made of a material softer than the bearing 35, the pressing member 40 is likely to be worn. On the other hand, even if the pressing member 40 is made of a material softer than the bearing 35 , the rotation restricting portion 50</b>A can prevent the pressing member 40 from coming loose from the opening 12 .

According to this embodiment, the outer ring 35a of the bearing 35 abuts against the flange portion 14 and the pressing member 40 in the axial direction. According to such a configuration, the bearing 35 is reliably held while suppressing rattling in the axial direction.

According to this embodiment, the pressing member 40 is provided with the film 61 . The film 61 can suppress wear of the pressing member 40 , suppress loosening of the pressing member 40 that presses the bearing 35 , and suppress rattling of the bearing 35 .

According to the present embodiment, the film 61 reduces the coefficient of friction of the pressing member 40 compared to the base material, thereby suppressing wear of the bearing 35 due to pressure. Therefore, it is possible to suppress loosening of the pressing member 40 that presses the bearing 35 and to prevent the bearing 35 from rattling.

According to this embodiment, the film 61 covers at least the portion of the pressing member 40 that contacts the bearing 35 . Accordingly, by providing the minimum coating 61, wear of the pressing member 40 can be suppressed.

According to this embodiment, the sealing member 70 is provided between the female threaded portion 15 of the housing 11 and the male threaded portion 45 of the pressing member 40 . It is possible to suppress the loosening in the direction of separating from each other. Accordingly, loosening of the pressing member 40 can be prevented without increasing the tightening force (axial force) of the pressing member 40 to prevent loosening. As a result, it is possible to suppress the need to increase the strength of the opening 12 (housing 11) provided with the female screw portion 15 to which the male screw portion 45 of the pressing member 40 is fastened, thereby suppressing an increase in the size and cost of the housing 11. can be done. As a result, it is possible to suppress loosening of the pressing member 40 that presses the bearing 35 and to suppress rattling of the bearing 35 while suppressing an increase in size and cost of the housing 11 .

(Modification)

FIG. 5 is a perspective view showing the appearance of a motor in a modification of the above embodiment. The motor of this modified example differs from the motor described above only in the structure of the rotation restricting portion 50B. In addition, the same code|symbol is attached|subjected about the component of the same aspect as the above-mentioned embodiment, and the description is abbreviate|omitted.

As shown in FIG. 5, the pressing member 40 is rotated inside the opening 12 by the rotation restricting portion 50B, and the loosening of the male thread portion 45 from the female thread portion 15 is restricted. The rotation restricting portion 50B consists of at least one welded portion 52. As shown in FIG. The welded portion 52 is provided at the boundary between the outer peripheral edge of the pressing member 40 and the inner peripheral edge of the opening 12 . In the present embodiment, the welded portions 52 are provided at four locations equidistantly in the circumferential direction on the boundary portion between the outer peripheral edge of the pressing member 40 and the inner peripheral edge of the opening 12 . Each welded portion 52 is provided by spot welding across the outer peripheral edge of the pressing member 40 and the inner peripheral edge of the opening 12 . Also, the welded portion 52 may be continuously provided in the circumferential direction along the boundary portion between the outer peripheral edge of the pressing member 40 and the inner peripheral edge of the opening 12 . The welding portion 52 restrains the pressing member 40 from rotating inside the opening 12 .

According to this modification, as in the above-described embodiment, a rotation restricting portion 50B that restricts the pressing member 40 from rotating inside the opening 12 is provided. As a result, it is possible to suppress loosening of the pressing member 40 in a direction away from the bearing 35 in the axial direction. Accordingly, loosening of the pressing member 40 can be prevented without increasing the tightening force (axial force) of the pressing member 40 to prevent loosening. As a result, it is possible to suppress the need to increase the strength of the opening 12 (housing 11) provided with the female screw portion 15 to which the male screw portion 45 of the pressing member 40 is fastened, and to suppress the increase in the size and cost of the housing 11. can. As a result, it is possible to suppress loosening of the pressing member 40 that presses the bearing 35 and to suppress rattling of the bearing 35 while suppressing an increase in size and cost of the housing 11 .

Further, in the above embodiment, the pressing member 40 is provided with the film 61, but the present invention is not limited to this.

FIG. 6 is a cross-sectional view showing the configuration of the essential parts of the motor in another modified example of the above embodiment.

As shown in FIG. 6, an inclusion 62 made of a material harder than the pressing member 40 is provided between the pressing member 40 and the bearing 35 in the axial direction. The inclusion 62 is annular and has a so-called washer shape. The inclusion 62 contacts the outer ring 35a of the bearing 35 on the one surface 62a side, and contacts the pressing member 40 on the other surface 62b side. The inclusion 62 has a larger contact area with the pressing member 40 than the contact area with the bearing 35 .

According to this modification, an inclusion 62 made of a material harder than the pressing member 40 is provided between the pressing member 40 and the bearing 35 . Furthermore, the contact area of the inclusion 62 with the pressing member 40 is larger than the contact area with the bearing 35 . As a result, when the bearing 35 is repeatedly pressed by the reaction force F1, the pressure per unit area input from the outer ring 35a of the bearing 35 to the pressing member 40 via the inclusion 62 is reduced. Therefore, the pressing member 40 is less likely to loosen from the opening 12 .

It should be noted that the above inclusion 62 can be provided together with the coating 61 of the above embodiment. Moreover, the inclusion 62 may be a material that is harder than the pressing member 40, such as a washer made of a metal material such as steel (iron-based alloy).

Moreover, the inclusions 62 are not limited to be annular, and a plurality of inclusions may be provided at intervals in the circumferential direction around the central axis J.

Applications of the motors of the above-described embodiments and modifications thereof are not particularly limited.

Moreover, in the above-mentioned embodiment or its modification, although the ball bearing was illustrated as the bearing 35, it is not restricted to this. For example, a needle roller bearing or the like can be used as the bearing 35 .

Moreover, although the film 61, the inclusion 62, and the sealing material 70 are provided in the above-described embodiment or its modification, these may be omitted.

An embodiment of the present invention and its modification have been described above, but each configuration and combination thereof in the embodiment and modification are examples, and additional configurations may be added without departing from the scope of the present invention. , omissions, substitutions and other changes are possible. Moreover, the present invention is not limited by the embodiments.

DESCRIPTION OF SYMBOLS 10... Motor 11... Housing 12... Opening 14... Flange part (bearing holding part) 15... Female screw part 20... Stator 30... Rotor 35... Bearing 35a... Outer ring 35b... Inner ring 35c... Ball 40 Pressing member 45 Male screw portion 50A, 50B Rotation restricting portion 51 Crimped portion 51a Convex portion 51b Concave portion 52 Welding portion 61 Coating 62 Inclusion 70 ... sealing material, 100 ... member to be driven

Claims (8)

a cylindrical housing having an opening at one end in the axial direction and a female screw portion on the inner peripheral surface of the opening;
a stator provided radially inside the housing;
a rotor provided radially inward of the stator and connected to a member to be driven;
a bearing supported by the housing and supporting the rotor rotatably about the central axis of the rotor;
a bearing holding portion extending radially inward from the housing and abutting against the bearing from the other side in the axial direction;
a pressing member provided in the opening of the housing, having a male threaded portion fastened to the female threaded portion on an outer peripheral surface, and pressing the bearing toward the other side in the axial direction;
a rotation restraining portion that restrains the pressing member from rotating inside the opening ;
The motor, wherein the rotation restricting portion comprises at least one crimped portion provided so as to straddle a boundary portion between an outer peripheral edge of the pressing member and an inner peripheral edge of the opening on one axial end face of the housing. a cylindrical housing having an opening at one end in the axial direction and a female screw portion on the inner peripheral surface of the opening;
a stator provided radially inside the housing;
a rotor provided radially inward of the stator and connected to a member to be driven;
a bearing supported by the housing and supporting the rotor rotatably about the central axis of the rotor;
a bearing holding portion extending radially inward from the housing and abutting against the bearing from the other side in the axial direction;
a pressing member provided in the opening of the housing, having a male threaded portion fastened to the female threaded portion on an outer peripheral surface, and pressing the bearing toward the other side in the axial direction;
a rotation restraining portion that restrains the pressing member from rotating inside the opening;
The rotation restricting portion comprises at least one welded portion provided so as to straddle a boundary portion between the outer peripheral edge of the pressing member and the inner peripheral edge of the opening on one end face in the axial direction of the housing.
motor. The crimped portion is
a protrusion provided on one of the outer peripheral edge of the pressing member and the inner peripheral edge of the opening and protruding in the radial direction toward the other of the outer peripheral edge of the pressing member and the inner peripheral edge of the opening;
a concave portion provided in the other of the outer peripheral edge of the pressing member and the inner peripheral edge of the opening, recessed toward one of the outer peripheral edge of the pressing member and the inner peripheral edge of the opening, and accommodating at least part of the convex portion; ,
has a
A motor according to claim 1. wherein the housing and the pressing member are made of an aluminum alloy,
A motor according to any one of claims 1 to 3 . The bearing is a ball bearing comprising an outer ring, an inner ring provided radially inside the outer ring, and a plurality of balls provided between the outer ring and the inner ring,
the outer ring abuts against the bearing holding portion and the pressing member in the axial direction;
The motor according to any one of claims 1-4 . The inner diameter of the female threaded portion and the outer diameter of the male threaded portion are larger than the inner diameter of the bearing holding portion.
A motor according to any one of claims 1 to 5 . The pressing member is provided with a coating made of a material harder than a material constituting the pressing member, at least on a surface that abuts the bearing in the axial direction.
A motor according to any one of claims 1 to 6 . an inclusion made of a material harder than the pressing member is provided between the pressing member and the bearing in the axial direction;
The inclusion has a contact area with the pressing member that is larger than a contact area with the bearing,
A motor according to any one of claims 1-7 .

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