CN110495078A - motor - Google Patents

Abstract

Motor includes rotor；Stator；Resin enclosure, at least insulator and winding of sealed stator；Multiple bearings, rotation is being pivotally supported along the position that axial direction is separated from each other can to rotate by they；And cover, covering resin shell, stator have the multiple bearing storage members stored respectively to multiple bearings, bearing storage member and the cover are the components of electric conductivity, and cover directly or indirectly conducts respectively with multiple bearing storage members.

Description

motor

technical field

This invention relates to motors.

Background technique

Conventional motors are disclosed in Patent Document 1, Patent Document 2, and the like. In the inner rotor type molded motor described in Patent Document 1, the rotor is disposed on the inner diameter side of the stator whose outer contour is molded by molding resin, and the output side and the anti-output side of the output rotating shaft of the rotor are bearings. Support for rotation. Furthermore, the bearings are housed in bearing housings formed on brackets arranged on both sides of the output side and the anti-output side of the outer contour of the stator.

In this inner rotor type molded motor, when a potential difference is generated between the bracket on the output side and the bracket on the anti-output side, a current flows in the bearing. When electric current flows in the bearing, electrical erosion occurs, which causes vibration and noise of the motor. Therefore, in the inner rotor type molded motor disclosed in Patent Document 1, the bracket on the output side and the bracket on the anti-output side are electrically connected through the conduction plate.

In addition, the brushless DC motor described in Patent Document 2 has a rotor and a stator. The stator has: an annular stator core forming a rotating magnetic field with the rotor; and a stator coil wound around the stator core. Furthermore, there is a structure in which the stator is molded integrally with a case made of resin, and the outer surface of the case is covered with a protective cover made of metal.

This brushless DC motor dissipates the heat generated by the stator coil to the outside through the casing made of resin, and covers the outer surface of the casing with a protective cover made of metal, thereby preventing the casing from being damaged due to external impact. body damage.

prior art literature

patent documents

Patent Document 1: Japanese Patent Laid-Open No. 2012-210064

Patent Document 2: Japanese Patent Application Laid-Open No. 9-261935

Contents of the invention

The problem to be solved by the invention

In the inner rotor type molded motor described in Patent Document 1, the outer contour molded by molding resin is exposed to the outside, and therefore the outer contour may be damaged by an impact from the outside. In addition, although the outer contour can be protected by attaching the protective cover having the structure of Patent Document 2, man-hours are required for attaching each component, which leads to complicated assembly work and increased cost.

Therefore, it is an object of the present invention to provide a motor that reduces assembly man-hours, protects against external impacts, and counteracts electric corrosion of bearings.

means to solve the problem

An exemplary motor of the present invention is characterized in that the motor has: a rotor having a rotating shaft extending along a central axis; outer peripheral surfaces of the rotor are opposed in the radial direction; a resin case sealing at least the insulator and the winding of the stator; a plurality of bearings supporting the rotating shaft at positions separated from each other in the axial direction In order to be able to rotate; and a cover that covers the resin case, the stator has a plurality of bearing receiving parts for respectively storing the plurality of bearings, the bearing receiving parts and the cover are conductive parts, and The cover is in direct or indirect electrical communication with the plurality of bearing housing components.

Invention effect

According to the illustrated motor of the present invention, it is possible to protect against external impact and counteract electric corrosion of the bearing while reducing assembly man-hours.

Description of drawings

Fig. 1 is an exploded perspective view of an example of the motor of the present invention.

Fig. 2 is a sectional view of the motor shown in Fig. 1 .

Fig. 3 is a perspective view of a stator core.

Fig. 4 is a perspective view of a stator core included in the stator.

Fig. 5 is a perspective view of a rotor.

6 is a partial sectional view showing a resin case and a cover of a modified example of the motor of the first embodiment.

7 is a partial sectional view showing a resin case and a cover of another modified example of the motor of the first embodiment.

8 is a partial cross-sectional view showing a first bearing housing member and its surroundings in another modified example of the motor of the first embodiment.

9 is a partial cross-sectional view showing a first bearing housing member and its surroundings in another modified example of the motor of the first embodiment.

Fig. 10 is an exploded perspective view of another example of the motor of the present invention.

Fig. 11 is a sectional view of the motor shown in Fig. 10 .

Fig. 12 is a sectional view of still another example of the motor of the present invention.

Fig. 13 is an exploded perspective view of still another example of the motor of the present invention.

Fig. 14 is a sectional view of the motor shown in Fig. 13 .

Fig. 15 is a sectional view of still another example of the motor of the present invention.

Fig. 16 is a sectional view of still another example of the motor of the present invention.

Detailed ways

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

<1. First Embodiment>

Fig. 1 is an exploded perspective view of an example of the motor of the present invention. Fig. 2 is a sectional view of the motor shown in Fig. 1 . In addition, in the following description, the direction in which the central axis Ax extends, that is, the left-right direction in FIG. 2 is taken as the axial direction. In addition, a direction perpendicular to the axial direction is defined as a radial direction, and a tangential direction of a circle centered on the axis line is defined as a circumferential direction.

In addition, in this specification, the axial direction is set as follows with reference to FIG. 2 . That is, in FIG. 2 , the direction toward the axial right is referred to as the first direction Op, and the direction toward the left is referred to as the second direction Or. In addition, "left direction" and "right direction" in this specification are set for description. Therefore, these directions do not limit the orientation when the motor A is actually used.

＜1.1 Motor Structure＞

As shown in FIG. 1 , the motor A of this embodiment has a stator 1 , a resin case 2 , a cover 3 , a rotor 4 , a first bearing 51 , and a second bearing 52 . The resin case 2 covers the outer peripheral surface of the stator 1 . That is, the motor A is a so-called molded motor in which the stator 1 is sealed with a resin case 2 . The rotor 4 is disposed inside the stator 1 . The rotor 4 has a rotation shaft 40 extending along a central axis Ax. Furthermore, the rotating shaft 40 is supported by the first bearing 51 and the second bearing 52 and is rotatable relative to the stator 1 . That is, the motor A of the present embodiment is an inner rotor type DC brushless motor in which the rotor 4 rotates inside the stator 1 . Also, a plurality of bearings (51, 52) rotatably support the rotating shaft 40 at positions separated from each other in the axial direction.

<1.2 Stator structure>

The stator 1 will be described with reference to the new drawings. Fig. 3 is a perspective view of a stator core. Fig. 4 is a perspective view of a stator core included in the stator. As shown in FIGS. 3 and 4 , the stator 1 has a stator core 11 , an insulator 12 , and a winding 13 . Furthermore, the stator 1 has a plurality of windings 13 wound around a stator core 11 , which is opposed to the outer peripheral surface of the rotor 4 in the radial direction, via an insulator 12 . As shown in FIG. 2 , the stator 1 has a first bearing accommodating member 61 in which the first bearing 51 is accommodated, and a second bearing accommodating member 62 in which the second bearing 52 is accommodated. That is, the stator 1 has a plurality of bearing accommodating members (61, 62) for respectively accommodating a plurality of bearings (51, 52).

The stator core 11 has electrical conductivity. As shown in FIG. 4 , the stator core 11 has an annular core back 111 and teeth 112 . The core back 111 is in the shape of a ring extending in the axial direction. The tooth portion 112 protrudes radially inward from the inner peripheral surface of the core back 111 . As shown in FIG. 4 , stator core 11 has twelve tooth portions 112 . The teeth 112 are arranged at equal intervals in the circumferential direction. That is, in the motor A of this embodiment, the stator 1 has 12 slots.

The insulator 12 covers the stator 11 . The insulator 12 is a molded body of resin. The insulator 12 covers the entire tooth portion 112 and covers both axial end surfaces of the core back 111 . The insulator 12 has: an insulator tooth portion 121 covering the tooth portion 112 ; and an insulator core back 122 covering at least an axial end portion of the core back 111 . The winding 13 is formed by winding a conductive wire around the tooth portion 112 (insulator tooth portion 122 ) covered with the insulator 12 . The stator core 11 is insulated from the winding 13 by the insulator 12 . In addition, in this embodiment, the insulator 12 is a molded body of resin, but it is not limited thereto. A structure capable of insulating the stator core 11 from the winding 13 can be widely adopted.

As described above, the insulator 12 insulates the stator core 11 from the winding 13 . Therefore, in the stator core 11 , the radially outer peripheral surface of the core back 111 may be exposed without being covered with the insulator 12 . In addition, the stator core 11 may have a structure in which electromagnetic steel sheets are laminated, or may be a single member obtained by firing powder, casting, or the like. In addition, the stator core 11 may have a structure that can be divided into a divided core including one tooth portion 112 , or may have a structure formed by winding a band-shaped member. In the radial center of the stator 1 , a rotor 4 is disposed so as to penetrate in the axial direction.

Coil 13 is disposed on each tooth portion 112 of stator core 11 . That is, in the motor A, 12 coils 13 are arranged. Furthermore, the 12 windings 13 included in the stator 1 are divided into three systems (hereinafter referred to as three phases) according to the timing of supplying current. These three phases are respectively referred to as a U phase, a V phase, and a W phase. That is, the stator 1 has four U-phase windings, four V-phase windings, and four W-phase windings. In addition, in the following description, the winding of each phase is collectively called the winding 13 and demonstrated.

In addition, the stator 1 has an overlapping wire portion 131 that connects the plurality of windings 13 to each other or electrically connects the windings 13 to a control circuit (not shown) that is mounted on the motor A. on the substrate Bd. Furthermore, the bonding wire portion 131 is disposed on the wiring portion 120 included in the insulator core back 122 covering the axial end surface of the core back 111 of the insulator 12 . In addition, as shown in FIG. 2 , the stator 1 has the wiring portion 120 on which the overlapping wires 131 are arranged on the radially outer surface of the insulator 12 covering the end surface of the core back 111 on the Op side in the first direction.

＜1.3 Structure of resin case and cover＞

As shown in FIG. 1, FIG. 2, etc., the resin case 2 has a cylindrical shape. The resin case 2 is a resin molded body in which the stator core 11 is sealed. That is, the resin case 2 seals at least the insulator 13 and the winding 12 of the stator 1 . In addition, as shown in FIG. 2 , in the motor A, the radially outer surface of the stator core 11 is also covered. The resin case 2 has a bottomed cylindrical shape in which at least a part of the end on the Op side in the first direction is closed. Also, a resin case hole 20 extending in the axial direction is provided at a radially central portion of the bottom.

On the radially outer side of the resin case hole 20 on the surface on the Op side of the first direction of the bottom, a concave hole 21 recessed in the axial direction is provided. The rotary shaft 40 attached to the rotor 4 penetrates the resin case hole 20 in the axial direction. In addition, the first bearing housing member 61 is fixed to the resin case hole 20 by insert molding. Note that details of the first bearing housing portion 61 will be described later.

As shown in FIG. 1 , FIG. 2 , etc., the cover 3 covers the resin case 2 . The cover 3 has a bottomed cylindrical shape in which at least a part of the end on the Op side in the first direction is closed. That is, the cover 3 has a cylindrical shape extending in the axial direction. The cover 3 is formed, for example, by extruding a metal plate. Furthermore, a cover hole 30 penetrating in the axial direction is provided at the radially central portion of the bottom of the cover 3 . Further, on the outside in the radial direction of the cover hole 30, there is a housing contact portion 31 protruding inward in the axial direction (the second direction Or side in FIG. 2 ). That is, the cover 3 has a case contact portion 31 protruding inward at the radial center portion of the bottom, and a cover hole 30 at the center of the case contact portion 31 .

The resin case 2 is inserted into the cover 3 on the Op side in the first direction in FIG. 2 . Furthermore, a press-fit portion 22 to be described later is press-fitted into the cover 3 . When the resin case 2 is press-fitted into the cover 3 , the case contact portion 31 overlaps with the concave hole 21 in the axial direction. Furthermore, the resin case hole 20 and the cover hole 30 also overlap in the axial direction. The rotation shaft 40 penetrates the resin case hole 20 and the cover hole 30 .

In addition, when the resin case 2 is press-fitted into the cover 3 , the case contact portion 31 comes into contact with the concave hole 21 . The housing contact portion 31 is in axial contact with the recessed hole 21 . Furthermore, the conductive portion 312 extending in the axial direction (here, the outer side, that is, the first direction Op side) is formed by a single member at the radially inner end portion of the case contact portion 31 . Furthermore, the conductive portion 312 is press-fitted into the outer peripheral surface of the first bearing housing member 61 . That is, the first bearing housing member 61 is directly electrically connected to the cover 3 by being press-fitted into the conductive portion 312 . (Claim 1) In addition, it has a conductive portion 312 that electrically conducts the bearing housing member 61 and the cover 3 . In addition, the radial inner side of the conductive portion 312 is the cover hole 30 , and the entry of gas, water, dust, dust, etc. from the contact portion between the cover hole 30 and the first bearing housing member 61 is suppressed.

Next, attachment of the resin case 2 to the cover 3 will be described. The resin case 2 has a press-fit portion 22 and a concave portion 23 on its radially outer peripheral surface. That is, the resin case 2 has a press-fit portion 22 that is press-fit into the cover 3 . As shown in FIG. 2 , the press-fit portion 22 is disposed on a portion of the outer peripheral surface of the resin case 2 overlapping with the stator core 11 in the radial direction. That is, when the resin case 2 is viewed in the radial direction, the press-fit portion 22 overlaps the stator core 22 . The resin case 2 is inserted into the opening of the cover 3 from the end on the side where the concave portion 23 is formed. Then, the resin case 2 is fixed to the cover 3 by press fitting.

That is, the resin case 2 is press-fitted into the inner peripheral surface of the cover 3 at the press-fit portion 22 . The press-fit portion 22 is disposed at a position overlapping with the stator core 11 in the radial direction. During press-fitting, radial and axial forces act on the resin case 2 from the cover 3 . Since the press-fit portion 22 is disposed at a position radially overlapping with the stator core 11, even if force is applied from the cover 3 during press-fit, the resin case 2 is less likely to be deformed, etc., wherein the stator core 11 is stronger than the resin The resin of the case 2 is high.

The concave portion 23 overlaps in the radial direction the wiring portion 120 of the insulator 12 on the outer peripheral surface of the resin case 2 , and the wiring portion 120 is provided with the bonding wire portion 131 . The concave portion 23 is provided at an end portion of the resin case 2 on the Op side in the first direction, and is continuously formed in the circumferential direction. In this embodiment, it is formed at the radial end of the resin case 2, but it is not limited thereto.

In addition, depending on the conditions of the installation site of the motor A, water contained in the air inside the motor A may condense to accumulate condensed water. Air also accumulates in the concave portion 23, and moisture contained in the accumulated air may condense. Therefore, the groove 200 extending from the concave portion 23 toward the second direction Or side is arranged on the outer peripheral surface of the resin case 2 . Furthermore, a drain hole 301 connecting the outside of the cover 3 to the groove 200 is arranged at a position of the cover 3 continuous with the groove 200 .

As a result, the condensed water accumulated in the concave portion 23 passes through the groove 200 and is discharged to the outside through the drain hole 301 . In addition, for example, in the case of adopting a structure that is not or is not easily affected by condensation due to circuit insulation or the like, the groove 200 and the drain hole 301 may be omitted. Even if the groove 200 and the drain hole 301 are omitted, the condensed water evaporates in the air in the recessed portion 23 due to the heat when the motor A is driven.

The resin case 2 is inserted into the cover 3 from the side provided with the recessed portion 23 in the axial direction, and is fixed by press fitting. When the resin case 2 is press-fitted into the cover 3 , a gap Gp is formed in the radial direction between the portion where the concave portion 23 is formed and the inner surface of the cover 3 .

In addition, as shown in FIG. 2 , the portion of the recess 23 of the resin case 2 has a thinner radial thickness than other portions of the resin case 2 . That is, the portion where the concave portion 23 is provided is the thin portion 24 that is thinner than other portions. Electric current flows in the overlapping wire portion 131 , and may heat the overlapping wire portion 131 . At this time, since the thin portion 24 is formed, the heat of the overlapping line portion 131 is easily released to the outside of the resin case 2 .

<1.4 Structure of the rotor>

Fig. 5 is a perspective view of a rotor. As shown in FIG. 5 , the rotor 4 has a rotor core 41 , a plurality of magnets 42 , and a molded portion 43 . The rotor core 41 includes: a cylindrical member 411 extending in the axial direction; and a shaft support member 412 arranged radially inside the cylindrical member. The cylindrical member 411 and the shaft support member 412 are fixed to each other by the molding part 43 which is a molded body of resin. The rotor core 41 is a magnetic body. The rotor core 41 may be a laminated body in which magnetic plates are laminated in the radial direction, or may be a molded body formed as the same member by sintering powder, for example.

The rotating shaft 40 has a cylindrical shape. The rotary shaft 40 penetrates through the radial center portion of the shaft support member 412 of the rotor core 41 . The rotating shaft 40 and the shaft supporting member 412 are relatively fixed. In addition, press-fitting, welding, etc. are mentioned as a fixing method, but it is not limited to this. A method capable of fixing the rotating shaft 40 and the shaft support member 412 can be widely adopted. That is, the rotating shaft 40 is fixed to the rotor 4, and when the rotor 4 is rotated, the rotating shaft 40 is rotated around the central axis Ax.

The plurality of magnets 42 are arranged radially outside of the rotor core 41 . In the rotor 4 of the present embodiment, a plurality of magnets 42 are arranged along the circumferential direction. For example, rotor core 41 has eight magnets 42 . In addition, in this embodiment, a plurality of magnets 42 are arranged, but it is not limited thereto. For example, for a cylindrical magnetic body, a magnet in which N poles and S poles are alternately magnetized in the circumferential direction may be used.

That is, in the rotor core 41 , the N pole and the S pole are a pair of magnetic poles, and there are a plurality of the pair of magnetic poles. The magnet 42 is fixed to the rotor core 41 by resin molding or the like, for example. In addition, the fixing method of the magnet 42 is not limited to resin molding, and methods such as adhesion, welding, and mechanical fixing methods that do not or are unlikely to adversely affect the rotation of the rotor 4 can be used.

<1.5 Bearing structure>

The rotary shaft 40 is press-fitted into the first bearing 51 and the second bearing 52 at two locations separated in the axial direction. That is, the rotating shaft 40 is rotatably supported by two axially different locations of the first bearing 51 and the second bearing 52 . The end portion of the rotary shaft 40 on the second direction Or side is press-fitted into the inner ring of the second bearing 52 . The inner ring of the first bearing 51 is press-fitted with a portion on the Op side in the first direction relative to the portion of the rotary shaft 40 that is press-fitted into the second bearing 52 .

The first bearing 51 is housed in the first bearing housing member 61 . The second bearing 52 is housed in a second bearing housing member 62 . The first bearing accommodating member 61 and the second bearing accommodating member 62 are directly or indirectly fixed to the resin case 2, and details thereof will be described later. Therefore, the rotating shaft 40 is rotatably supported by the resin case 2 (covered stator 1 ) via a pair of bearings 51 and 52 .

A shaft retaining ring 401 is attached to the first direction Op side of the rotating shaft 40 , and a shaft retaining ring 402 is attached to an end portion on the second direction Or side. The retaining ring 401 is in contact with the first bearing 51 . The retaining ring 402 is in contact with the second bearing 52 . In addition, the shaft retaining ring 401 and the shaft retaining ring 402 are fixed by being fitted into a groove provided on the outer peripheral surface of the rotating shaft 40 . The retaining ring 401 is in contact with the second direction Or side of the inner ring of the first bearing 51 . The stop ring 401 restricts the movement of the rotating shaft 40 to the Op side in the first direction relative to the first bearing 51 .

The retaining ring 402 is in contact with the inner ring of the second bearing 52 on the Op side in the first direction. The stop ring 402 restricts the movement of the rotating shaft 40 in the second direction Or side with respect to the second bearing 52 . The axial movement of the first bearing 51 and the second bearing 52 with respect to the stator 1 is relatively restricted, so that the axial movement of the rotating shaft 40 with respect to the stator 1 is restricted. In addition, as the retaining rings 401 and 402, for example, retaining rings for shafts called C rings and E rings are generally used, but are not limited thereto. A structure that restricts the movement of the rotary shaft 40 by contacting the inner rings of the pair of bearings 51 and 52 can be widely used. In addition, in each embodiment in this specification, although the rotating shaft 40 is rotatably supported by two bearings (1st bearing 51 and the 2nd bearing 52), it is not limited to this. It may also be supported by three or more bearings.

<1.6 Structure of Bearing Housing>

Here, the first bearing housing member 61 and the second bearing housing member 62 are made of metal such as iron or brass. That is, the bearing housing members (61, 62) and the cover 3 have electrical conductivity.

<1.6.1 1st Bearing Storage Part>

The first bearing housing member 61 has a cylindrical shape capable of housing the first bearing 51 therein. One end portion in the axial direction of the first bearing housing member 61 has an end surface portion 610 penetrating in the axial direction at a central portion in the radial direction. In addition, the end portion on the other axial side of the first bearing housing member 61 has a flange portion 611 extending radially outward. At least a part of the flange portion 611 is insert-molded in the resin case 2 . The first bearing housing portion 61 is fixed to the resin case 2 by insert molding. In addition, the flange portion 611 may have a penetrating portion in the axial direction. By filling the penetration portion with resin during insert molding, the movement in the circumferential direction of the first bearing housing member 61 is restricted, that is, the rotation is stopped.

In addition, if the resin is used to securely prevent the rotation, the penetrating portion is not limited to a hole, and may be, for example, a concave portion dented radially inward or a convex portion protruding radially outward. In addition, the flange portion 611 itself may be formed into a polygonal shape (for example, a triangle, a quadrangle), or an ellipse to prevent rotation. The first bearing accommodating member 61 is fixed to the resin case 2 so that the center axis thereof coincides with the center axis Ax of the stator 1 covered by the resin case 2 . The outer ring of the first bearing 51 is press-fitted into the inside of the first bearing housing member 61 .

<1.6.2 Second bearing housing part>

As shown in FIG. 2 , the second bearing housing member 62 holds the second bearing 52 . The second bearing housing member 62 has a housing portion 621 and an outer cylinder portion 620 . The housing portion 621 has a cylindrical shape and accommodates the second bearing 52 therein. The outer ring of the second bearing 52 is press-fitted into the housing portion 621 .

The diameter of the outer cylinder portion 620 is larger than that of the housing portion 621 , and the end portion of the cover 3 on the second direction Or side is press-fitted into the outer cylinder portion 620 . In addition, a portion of the end portion of the cover 3 on the second direction Or side that is press-fitted into the outer cylindrical portion 620 is the cover press-fitting portion 300 . That is, the cover 3 is electrically connected to each of the plurality of bearing housing members (61, 62) directly.

That is, after the second bearing 52 is press-fitted into the housing portion 621 , the cover press-fitting portion 300 of the cover 3 is press-fitted into the outer cylinder portion 620 of the second bearing housing member 62 . Then, by press-fitting the resin case 2 into the second bearing housing member 62 , the second bearing 62 is fixed to the stator 1 covered by the resin case 2 . The outer ring of the second bearing 52 is fixed to the stator 1 , and the central axis of the second bearing 52 coincides with the central axis Ax of the stator 1 .

As shown in FIG. 2 , the housing portion 621 and the outer cylinder portion 620 are formed of the same member. In addition, here, the second bearing housing member 62 is manufactured by rolling a metal plate. However, it is not limited to this.

In the conduction part between the cover 3 and the bearing storage part (the first bearing storage part 61), the outer peripheral surface of the bearing storage part (the first bearing storage part 61) has a hole which is pressed into the other side (the conductive part 312 of the cover 3). Cylindrical press-fit part 612 . In addition, at the conduction portion between the cover 3 and the bearing housing member (the second bearing housing member 62), the outer peripheral surface of the cover 3 has a press-fitting portion that is press-fitted into the other side (the outer cylinder portion 620 of the second bearing housing member 62). (Cover pressing part 300).

＜1.7 Other Structure Department＞

As shown in FIG. 2 , in the motor A, the second direction Or side of the cover 3 is press-fitted into the outer cylinder portion 620 of the second bearing housing member 62 . Therefore, entry of foreign matter such as water, dust, and dust from the gap between the outer cylinder portion 620 and the cover press-fit portion 300 is suppressed. On the other hand, the first direction Op side of the motor A has a bearing accommodating portion hole through which the rotating shaft 40 passes through the end surface portion 610 of the first bearing accommodating portion 61 . In order not to interfere with the rotation of the rotating shaft 40 , the bearing accommodating portion hole has a size to form a gap with the rotating shaft 40 . Foreign substances such as water, dust, and dust are likely to infiltrate into the inside of the motor A through this gap. Therefore, the motor A has a bearing-side intrusion preventing member 71 and a shaft-side intrusion preventing member 72 for suppressing foreign matter from entering from the first bearing housing member 61 .

As shown in FIG. 2 , the bearing-side intrusion prevention member 71 covers the outer surface of the first bearing housing member 61 . Furthermore, it surrounds the outer side of the rotating shaft 40 and extends in the radial direction. In addition, the bearing-side intrusion preventing member 71 is formed of a material such as rubber, for example, and is in close contact with the first bearing housing member 61 . In addition, the bearing-side intrusion preventing member 71 is attached with a gap between it and the rotating shaft 40 , that is, maintained in non-contact.

In addition, the shaft-side intrusion preventing member 72 is disposed so as to surround the radially outer side of the bearing-side intrusion preventing member 71 . The shaft-side intrusion preventing member 72 is arranged in the groove 400 included in the rotating shaft 40 . Accordingly, axial movement of the shaft-side intrusion preventing member 72 is restricted. By reducing the space between the bearing-side intrusion preventing member 71 and the shaft-side intrusion preventing member 72 , entry of foreign matter into the motor A is suppressed. That is, by attaching the bearing-side intrusion preventing member 71 and the shaft-side intrusion preventing member 72 to the motor A at the same time, it is possible to prevent foreign matter from entering the motor A.

A portion of the front end of the axial intrusion preventing member 72 on the second direction Or side overlaps the concave hole 21 . In addition, the housing contact portion 31 of the cover 3 is also disposed in the recessed hole 21 , but the shaft side intrusion prevention member 72 is fixed to the rotating shaft 40 in a non-contact state with the housing contact portion 31 . That is, a part of the opening of the shaft-side intrusion prevention member 72 is arranged in the recessed hole 21 . Also, the housing contact portion 31 is not in contact with the shaft-side intrusion prevention member 72 , and thus does not restrict the rotation of the rotation shaft 40 .

In addition, the resin case 2 has a substrate Bd and a protective sheet Is at a position on the second direction Or side of the stator 1 . The board Bd is mounted with a control circuit (not shown) that controls the timing of supplying current to the plurality of windings 13, the magnitude of the current, and the like. In addition, there may be a case where the control circuit is provided outside the motor A, and in this case, the board Bd may also be omitted. The protection sheet Is is an insulating member disposed between the substrate Bd and the second bearing housing member 62 . In the case of employing a motor that does not have the substrate Bd, the protective sheet Is may be omitted.

＜1.8 Motor Action＞

The operation of the motor A shown above will be described. When the motor A is driven, current is supplied to the winding 13 . At this time, the winding 13 generates heat due to the current. At this time, the stator core 11 is also heated by the heat of the coil 13 . The stator core 11 and the winding 13 are covered with a resin case 2 . The heat of the stator core 11 and the winding 13 is transferred to the resin case 2 .

The heat of the resin case 2 is transferred to the cover 3 . The cover 3 is mainly made of metal, and its linear expansion coefficient is smaller than that of the resin case 2 . This creates a difference in the amount of deformation due to thermal expansion between the resin case 2 and the cover 3 . However, the resin case 2 and the cover 3 are press-fitted into the press-fit portion 22 of the resin case 2 . Therefore, the heat of the resin case 2 is transferred to the cover 3 to be dissipated, so that the thermal expansion of the resin case 2 is suppressed in the press-fit portion 22 .

In the resin case 2 , the insulator 12 is sealed by the resin case 2 at a portion shifted in the axial direction with respect to the press-fit portion 22 . The insulator 12 is resin, and the coefficient of linear expansion of the insulator 12 is larger than that of the stator core 11 . Therefore, the portion of the resin case 2 that does not overlap the stator core 11 in the radial direction deforms radially outward due to thermal expansion more than the press-fit portion 22 that radially overlaps the stator core 11 . In addition, since the distance between the stator core 11 and the cover 3 is greater, heat dissipation is inferior to that of the press-fit portion 22 . Therefore, defects such as strain and displacement of the resin case 2 occur due to a difference in the amount of deformation due to thermal expansion between the insulator 12 and the cover 3 .

In addition, with respect to the opening side of the cover 3 of the resin case 2 (the second direction Or side in FIG. 2 ), deformation of the resin case 2 due to thermal expansion is released toward the opening side. On the other hand, the rear side of the cover 3 (the first direction Op side in FIG. 2 ) does not have a site for releasing deformation due to thermal expansion. Therefore, in the motor A, there is a gap Gp between the cover 3 and the resin case 2 outside the insulator 12 in the radial direction.

Thus, the difference in the amount of deformation between the resin case 2 and the cover 3 at a position shifted in the axial direction from the stator core 11 of the resin case 2 (in particular, on the inner side in the press-fitting direction) is absorbed by the gap Gp. Accordingly, it is possible to suppress defects such as strain and displacement of the resin case 2 caused by a difference in the amount of deformation due to thermal expansion between the resin case 2 and the cover 3 .

According to the motor A of the present embodiment, a gap is provided in a portion where the difference in deformation due to heat between the resin case 2 and the cover 3 is large. The difference in thermal deformation between the resin case 2 and the cover 3 is absorbed by the gap Gp, thereby suppressing strain, offset, and the like due to the difference in thermal deformation. Moreover, by forming the recessed part 23 in the resin case 2, the gap between the resin case 2 and the cover 3 can be formed easily. In addition, a portion of the resin case 2 having the recess 23 , that is, a portion overlapping the recess 23 in the radial direction in FIG. 2 is a thin portion 24 that is thinner than other portions of the resin case 2 . Thus, by providing thin portion 24 , heat generated when current flows through bonding wire portion 131 can be easily discharged to the outside of resin case 2 .

<1.8.1 Electric corrosion of bearings>

In a conventional motor such as the cited document, if a potential difference occurs between the outer ring and the inner ring of the first bearing 51 or between the outer ring and the inner ring of the second bearing 52, the first bearing 51 may Discharge (sparks) are generated between the outer ring and the balls and between the inner ring and the balls of the second bearing 52 . The so-called galvanic corrosion of the bearing in which the surfaces of the outer ring, balls, and inner ring of the bearing are damaged by the discharge. Electrolytic corrosion of the first bearing 51 and the second bearing 52 causes vibration and noise of the motor A. As a cause of galvanic corrosion, a case where a switching element included in an inverter circuit for driving the motor A is driven with a high frequency and high voltage is mentioned. In addition, the potential state of the stator core, the rotor core 41, etc. are mentioned as a factor other than this.

Therefore, in the motor A of the present embodiment, the electric corrosion of the bearing is suppressed by the following method. The outer ring of the first bearing 51 is housed in a conductive first bearing housing member 61 . The outer ring of the second bearing 52 is housed in a second bearing housing member 62 having conductivity. Furthermore, the cover 3 is directly connected to the first bearing housing member 61 and the second bearing housing member 62 . Thus, by electrically conducting the outer ring of the first bearing 51 and the outer ring of the second bearing 52, the potential difference between the outer ring and the inner ring of the first bearing 51 and the outer ring and the inner ring of the second bearing 52 can be reduced. , thereby suppressing the generation of electrical corrosion of the bearings (51, 52) of the motor A.

In the motor A, the first bearing 51 and the second bearing 52 can be rotated with high precision for a long period of time by suppressing the occurrence of electric corrosion in the bearings. Thereby, the molding motor A can be operated stably for a long period of time. That is, the life of the molded motor A can be extended. In addition, since the outer ring of the first bearing 51 and the outer ring of the second bearing 52 are electrically connected to each other through the cover 3, there is no need for conductive members (for example, conductive tape, etc.). In addition, the cover 3 is an exterior body that protects the motor A from shock and vibration, and the first bearing housing member 61 is press-fitted into the conductive portion 312 of the cover 3 . In addition, the second bearing housing member 62 is press-fitted with an end portion of the cover 3 on the second direction Or side inside the outer cylinder portion 620 . As described above, the first bearing housing member 61 and the second bearing housing member 62 are fixed to the cover 3 by press fitting. Accordingly, the first bearing housing member 61 and the second bearing housing member 62 are less likely to be in a non-contact state with the cover 3 , and the occurrence of electrical corrosion can be stably suppressed.

＜1.9 Modifications＞

<1.9.1 Modification 1>

Modifications of the motor shown in this embodiment will be described with reference to the drawings. 6 is a partial cross-sectional view showing a resin case and a cover of a modified example of the motor of the present embodiment. The motor A1 shown in FIG. 6 has the same structure as the motor A shown in FIG. 2 except that the resin case 2a1 and the cover 3a1 are different. Therefore, the same reference numerals are attached to substantially the same parts, and detailed descriptions of the same parts are omitted.

In the motor A1 shown in FIG. 6 , the diameter of the outer peripheral surface of the resin case 2 a 1 gradually decreases toward the back side in the press-fitting direction, that is, the first direction Op side in FIG. 6 . That is, the outer peripheral surface of the resin case 2a1 is an inclined surface (tapered surface) whose diameter becomes smaller on the rear side in the press-fitting direction. Furthermore, the cover 3a1 has a shape in which the resin case 2a1 can be inserted. The cover 3a1 has a cylindrical shape, and its diameter gradually decreases toward at least the back side in the press-fitting direction of the inner peripheral surface, that is, the first direction Op side in FIG. 6 . That is, the inner diameter of the cover 3a1 becomes gradually smaller toward the press-fitting direction of the resin case 2a1. Insertion is facilitated by changing the shapes of the resin case 2a1 and the cover 3a1. In addition, since the press-fit portion 221 is an inclined surface, the amount of deformation of the resin case 2a1 at the time of press-fit can be reduced. Accordingly, it is easy to suppress generation of strain and the like in the stator 1 .

<1.9.2 Modification 2>

Modifications of the motor shown in this embodiment will be described with reference to the drawings. 7 is a partial cross-sectional view showing a resin case and a cover of another modified example of the motor of the present embodiment. The motor A2 shown in FIG. 7 has the same structure as the motor A shown in FIG. 2 except that the resin case 2a2 and the cover 3a2 are different. Therefore, the same reference numerals are attached to substantially the same parts, and detailed descriptions of the same parts are omitted.

In the motor A2 shown in FIG. 7 , the diameter of the outer peripheral surface of the resin case 2 a 2 becomes gradually smaller toward the back side in the press-fitting direction, that is, the first direction Op side in FIG. 7 . That is, the outer peripheral surface of the resin case 2a2 has a plurality of different shapes. Furthermore, the inner side of the outer peripheral surface of the resin case 2a2 in the press-fitting direction has a small diameter, and a step is formed in a part where the external shape changes. Furthermore, the cover 3a2 has a shape in which the resin case 2a2 can be inserted. The cover 3a2 has a cylindrical shape, and at least the diameter of the inner peripheral surface on the back side in the press-fitting direction, that is, on the first direction Op side in FIG. 7 is gradually reduced. That is, the inner diameter of the cover 3a2 becomes gradually smaller toward the press-fitting direction of the resin case 2a2.

Insertion becomes easy by having the shape of resin case 2a2 and cover 3a2. Moreover, positioning when inserting the resin case 2a2 into the cover 3a2 can be performed by bringing the level|step difference of the resin case 2a2 into contact with the level|step difference of the cover 3a2. And the press-fit part 222 of the resin case 2a2 contacts the press-fit part of the cover 3a2, and press-fit starts. Thereby, the force acting by press-fitting can be reduced. The amount of deformation of the resin case 2a2 at the time of press-fitting can be reduced. Accordingly, it is easy to suppress generation of strain and the like in the stator 1 .

＜1.9.3 Modification 3＞

Modifications of the motor shown in this embodiment will be described with reference to the drawings. 8 is a partial cross-sectional view showing a first bearing housing member and its surroundings in another modified example of the motor of the present embodiment. The motor A3 shown in FIG. 8 has the same structure as the motor A shown in FIG. 2 except that the resin case 2a3 and the cover 3a3 are different. Therefore, the same reference numerals are attached to substantially the same parts, and detailed descriptions of the same parts are omitted.

As shown in FIG. 8 , the resin case 2 a 3 has a notch 210 in the concave hole 21 . The notch 210 is disposed on an edge of the resin housing hole 20 and extends in the axial direction. In addition, the housing contact portion 31 of the cover 3 a 3 has a conductive portion 313 . The conductive portion 313 extends radially inward from the housing contact portion 31 . In addition, a part of the conductive portion 313 is bent and shifted toward the second direction Or side. The conductive portion 313 overlaps the notch 210 included in the resin case 2a3 in the axial direction.

The conductive portion 313 overlaps the flange portion 611 of the first bearing housing member 61 in the axial direction inside the notch 210 . Furthermore, the conductive portion 313 and the flange portion 611 are fixed by screws Bt. Accordingly, the conductive portion 313 is electrically connected to the flange portion 611 . That is, the cover 3a3 is electrically connected to the first bearing housing member 61 . Thus, the cover 3 a 3 electrically conducts the first bearing housing member 61 and the second bearing housing member 62 . In addition, in the motor A3, the outer ring of the first bearing 51 and the outer ring of the second bearing 52 have the same electric potential, and electric corrosion of each bearing is suppressed.

In addition, in the motor A3 of this modified example, the conductive member 313 and the flange portion 611 are fixed using the screw Bt, but the present invention is not limited thereto. For example, fixing tools such as rivets may also be used. In addition, welding, bonding using a conductive adhesive, or the like may be used. In addition, a structure capable of elastically deforming the conductive part 313 may be adopted, and the conductive part 313 may be pressed against the flange part 611 (contact with the flange part 611 ) by the elastic force of the conductive part 313 . In addition, these are just an example of the method of fixing the conductive part 313 and the flange part 611, and are not limited to this. A method of electrically conducting the conductive portion 313 and the flange portion 611 can be widely adopted.

<1.9.4 Modification 4>

Modifications of the motor shown in this embodiment will be described with reference to the drawings. 9 is a partial cross-sectional view showing a first bearing housing member and its surroundings in another modified example of the motor of the present embodiment. The motor A4 shown in FIG. 9 has the same structure as the motor A shown in FIG. 2 except that the cover 3a4 is different. Therefore, the same reference numerals are attached to substantially the same parts, and detailed descriptions of the same parts are omitted.

As shown in FIG. 9 , the cover 3 a 4 has a plurality of conductive portions 314 on the inner side in the radial direction of the housing contact portion 31 . Here, there are four conductive parts 314 . The conductive portion 314 extends radially inward, and its tip is bent in the axial direction (here, on the Op side in the first direction). The bent tip of the conductive portion 314 is in contact with the outer peripheral surface of the first bearing housing member 61 . The bent front end of the conductive portion 314 is inclined radially inward, and presses the outer peripheral surface of the first bearing housing member 61 inwardly. Accordingly, the tip of the conductive portion 314 is electrically connected to the first bearing housing member 61 . In addition, it is possible to employ a structure in which the conductive portion 314 is not easily deformed. In this case, the first bearing housing member 61 is press-fitted into the conductive portion 314 .

As shown in the motor A4, the cover 3a4 electrically conducts the 1st bearing accommodating member 61 and the 2nd bearing accommodating member 62. In addition, in the motor A4, the outer ring of the first bearing 51 and the outer ring of the second bearing 52 have the same electric potential, and electric corrosion of each bearing is suppressed.

<Second Embodiment>

Another example of the motor of the present invention will be described with reference to the drawings. Fig. 10 is an exploded perspective view of another example of the motor of the present invention. Fig. 11 is a sectional view of the motor shown in Fig. 10 . As shown in FIGS. 10 and 11 , the resin case 2 b of the motor B has a stepped portion 25 extending radially outward on the side in the second direction Or. The resin case 2b has a plurality (here, four) of steps 25 . The stepped portions 25 are arranged at equal intervals in the circumferential direction at the same position in the axial direction as that of the resin case 2b. Furthermore, the cover 3b has the contact part 311 which protrudes outward from the outer peripheral surface. When the resin case 2b is press-fitted into the cover 3b, the contact portion 311 comes into contact with the stepped portion 25 . The contact portion 311 is in contact with the surface of the stepped portion 25 in the press-fitting direction (the first direction Op side in FIG. 11 ).

In addition, the portion between the adjacent contact portions 311 in the circumferential direction of the cover 3 b extends toward the opening side (the second direction Or side in FIG. 11 ) rather than the contact portions 311 in the axial direction. In addition, in the motor B of the present embodiment, the resin case 2 b is directly press-fitted into the outer cylinder portion 620 of the second bearing housing member 62 .

The stepped portion 25 is a mounting convex portion for mounting the motor B to equipment. Therefore, a fixing tool such as a screw penetrates the stepped portion 25 . Furthermore, the contact part 311 which contacts the stepped part 25 formed by the same member as the resin case 2b is formed by the same member as the cover 3b whose strength is higher than the resin case 2b. Thereby, the motor B can be firmly fixed. In addition, even if vibration, shock, etc. act, the motor B is not easy to fall off. In addition, the number and position of the step portion 25 are not limited to the above, and may be changed in accordance with the shape and position of a mounting portion (not shown) of the device to which the motor B is mounted.

In the resin case 2b, the stepped portion 25 is a convex portion lined up in the circumferential direction. Furthermore, between the step portions 25 arranged in the circumferential direction is a curved surface continuous in the axial direction (that is, a curved surface obtained by cutting out a part of the cylindrical shape in the circumferential direction). The portion between the adjacent contact portions 311 in the circumferential direction of the cover 3 b has an extension portion 3111 extending in the second axial direction Or side. The end portion of the extending portion 3111 on the second direction Or side is the cover press-fitting portion 300 , and is press-fitted into the second bearing housing member 62 .

The cover 3 b electrically conducts the first bearing housing member 61 and the second bearing housing member 62 . That is, the outer ring of the first bearing 51 and the outer ring of the second bearing 52 have the same electric potential, and the occurrence of electric corrosion in the first bearing 51 and the second bearing 52 is suppressed.

Other features are the same as those of the first embodiment.

<3. Third Embodiment>

Fig. 12 is a sectional view of still another example of the motor of the present invention. In the motor C shown in FIG. 12 , the stator 1c and the resin case 2c are different, but the other parts are the same as the motor A of the first embodiment. Therefore, parts of the structure of the motor C that are substantially the same as those of the motor A are denoted by the same reference numerals, and detailed description of the same parts will be omitted.

As shown in FIG. 12 , in the stator 1 c of the motor C, an insulator core back 122 is provided at an end portion of the insulator 12 on the first direction Op side. Furthermore, the insulator core back 122 has the wiring part 120c in which the lap wire part 131 is arrange|positioned. Further, a concave portion 23c is formed at a position overlapping with the wiring portion 120c in the axial direction of the resin case 2c.

Moreover, the part of the recessed part 23c is the thin part 24c. Furthermore, there is a gap Gp between the cover 3c overlapping the recessed portion 23c in the axial direction.

The press-fit part 22 of the resin case 2c is arrange|positioned on the outer peripheral surface. Therefore, when the resin case 2c is press-fitted into the cover 3c, the force at the time of press-fitting acts on the outer peripheral surface of the resin case 2c. In the motor C, by arranging the concave portion 23c at the end portion on the first axial direction Op side, the force at the time of press-fitting is less likely to concentrate on the concave portion 23c. Thereby, shifting of the cover 3c with respect to the resin case 2c is also suppressed. Thereby, the resin case 2 c can be brought into a state where the first bearing housing member 61 and the second bearing housing member 62 are electrically connected.

Other features are the same as those of the first embodiment.

<4. Fourth Embodiment>

Still another example of the present invention will be described with reference to the drawings. Fig. 13 is an exploded perspective view of still another example of the motor of the present invention. Fig. 14 is a sectional view of the motor shown in Fig. 13 . The motor D of the present embodiment has the same structure as the motor A of the first embodiment except that the cover, the first bearing housing member 61d, the second bearing housing member 62d, and the bearing-side intrusion preventing member 71d are different. Therefore, in the structure of the motor D, the parts substantially the same as those of the motor A are denoted by the same reference numerals, and detailed descriptions of the same parts are omitted.

＜4.1 Cover＞

As shown in FIGS. 13 and 14 , the cover of the motor D has a first cover member 3da and a second cover member 3db. That is, the cover has: a first cover member 3da that covers the resin case 2 from one axial side (first direction Op side); and a second cover member 3db that covers the resin case 2 from the other axial side (second direction Or side). side) to cover the resin case 2. The first direction Op side of the resin case 2 is press-fitted into the first cover member 3da. In addition, the second direction Or side of the resin case 2 is inserted into the second cover member 3db. In addition, in the motor D of the present embodiment, the first direction Op side of the resin case 2 is press-fitted into the first cover member 3da, but the present invention is not limited thereto. For example, the second direction Or side of the resin case 2 may be press-fitted into the second cover member 3db. Alternatively, both may be press-fitted. Which one of the first cover member 3da and the second cover member 3db is to be press-fitted by the resin case 2 is determined according to the position of the press-fit portion 22 of the resin case 2 .

<4.2 Part 1 Cover>

As shown in FIGS. 13 and 14 , the first cover member 3 da has a bottomed cylindrical shape in which an end portion on the Op side in the first direction is closed. Furthermore, the end portion of the first cover member 3da on the second direction Or side has a first flange 32 extending radially outward. That is, the first cover member 3da has a first flange 32 extending radially outward from the outer peripheral surface. As shown in FIG. 11 , the first flange 32 is quadrangular (for example, square) when viewed in the axial direction. In addition, the first flange 32 has a shape capable of being attached to a mounting portion of a device (not shown) to which the motor D is mounted.

In addition, the radial center of the bottom of the first cover member 3da and the first bearing housing member 61d are formed of the same member. That is, the cover (first cover member 3da) holds at least one bearing (bearing 51) among the plurality of bearings. Moreover, 61 d of 1st bearing accommodation members and 71 d of bearing side intrusion prevention members are formed by the same member. That is, the first cover member 3da, the first bearing housing member 61d, and the bearing-side intrusion prevention member 71d are formed of the same member. That is, the first bearing housing member 61d protrudes toward the first direction Op side from the bottom of the first cover member 3da. The bearing-side intrusion prevention member 71d protrudes toward the Op side in the first direction from the radially central portion. Further, the bearing-side intrusion preventing member 71d protrudes toward the first direction Op side from the radial center portion of the end surface portion 610d on the first direction Op side of the first bearing housing member 61d. In addition, the bearing-side intrusion preventing member 71d is formed of the same member, that is, metal, as the first bearing housing member 61d.

The first bearing accommodating member 61d is formed of the same member as the first cover member 3da, but houses the first bearing 51 inside, and serves the same function as the first bearing accommodating member 61 of the motor A. In addition, although the material of the bearing-side intrusion prevention member 71d is also different, by using it together with the shaft-side intrusion prevention member 72, the intrusion of foreign matter such as water, dust, dust, etc. is suppressed. 71 has the same effect.

<4.3 Second cover part>

As shown in FIGS. 13 and 14 , the second cover member 3db is a cylindrical member extending in the axial direction. The second cover member 3db and the second bearing housing member 62d are formed of the same member. Moreover, the 2nd bearing accommodation member 62d is continuously formed in the end part of the 2nd direction Or side of 2nd cover member 3db. In addition, the second cover member 3db has a second flange 33 extending radially outward at an end portion on the Op side in the first direction. That is, the second cover member 3db has the second flange 33 extending radially outward from the outer peripheral surface. As shown in FIG. 11 , the second flange 33 is quadrangular (for example, square) when viewed in the axial direction. The second flange 33 has a shape overlapping the first flange 32 in the axial direction.

In the 2nd bearing housing part 62d, except that the part of the 2nd bearing housing part 62 of the motor A located in the outer cylinder part 620 is continuous with the 2nd cover part 3db by the same part, it has the same part as the 2nd bearing housing part used in the motor A. Part 62 has the same structure. That is, the second bearing housing member 62d has a housing portion 621d for housing the second bearing 52 . The cover (second cover member 3db) holds at least one bearing (bearing 52) among the plurality of bearings.

＜4.4 Motor Assembly＞

The resin case 2 is inserted into the first cover member 3da from the Op side in the first direction, and the press-fit portion 22 is press-fitted into the first cover member 3da. On the other hand, the 2nd cover member 3db only covers the resin case 2, and is not press-fitted. Therefore, the second cover member 3db in which the portion on the second direction Or side of the resin case 2 is inserted may be rotatable about the central axis Ax. Therefore, the surface of the second flange 33 on the first direction Op side has a protrusion 330 protruding toward the first direction Op side. The protrusion 330 is inserted into the positioning hole 320 provided in the first flange 32 . Accordingly, the circumferential positions of the first flange 32 and the second flange 33 , that is, the first cover member 3da and the second cover member 3db are adjusted.

The first flange 32 and the second flange 33 fix the first cover member 3da and the second cover member 3db to each other. Therefore, the first flange 32 and the second flange 33 have screw fixing holes through which fixing tools (here, screws) are inserted. And by fixing the 1st flange 32 and the 2nd flange 33 mutually, the 1st cover member 3da and the 2nd cover member 3db are mutually fixed. That is, when the first cover member 3da and the second cover member 3db cover the resin case 2, the first flange 32 and the second flange 33 are directly or indirectly connected.

The resin case 2 is press-fitted into the first cover member 3da, and the second cover member 3db is fixed to the first flange 32 of the first cover member 3da via the second flange 33 . Therefore, the relative positions of the stator 1 covered by the resin case 2 and the first bearing 51 and the second bearing 52 are determined. Furthermore, the rotating shaft 40 is rotatably supported by the first bearing 51 and the second bearing 52 .

That is, in the motor D, the rotating shaft 40 is supported by the first bearing 51 and the second bearing 52 attached to the first cover member 3da and the first cover member 3da into which the resin case 2 is press-fitted. The second cover member 3db. As a result, the rotor 4 is rotatably supported at a constant interval in the radial direction inside the stator 1 .

Thus, by covering the resin case 2 with the 1st cover member 3da and the 2nd cover member 3db, the length by which the press-fit part 22 is press-fitted can be shortened. Thereby, the force acting on the resin case 2 and the cover can be reduced, thereby suppressing deformation such as strain and displacement of the resin case 2 and the cover. In addition, thereby, the stator 1 and the rotor 4 can be accurately aligned, and performance degradation of the motor D can be suppressed.

In addition, the first bearing housing member 61d is formed of the same member as the conductive first cover member 3da, and the second bearing housing member 62d is formed of the same member as the conductive second cover member 3db. And the 1st cover member 3da and the 2nd cover member 3db are in contact. Thereby, the 1st bearing accommodation member 61d and the 2nd bearing accommodation member 62d are in the electrical conduction state. In addition, the first cover member 3da can also be said to be a part of the first bearing housing member 61d, and the second cover member 3db can also be said to be a part of the second bearing housing member 62d. Furthermore, in the motor D, the first cover member 3da is in direct contact with the second cover member 3db. That is, in the motor D, the cover is directly connected to the first bearing accommodating member 61d and the second bearing accommodating member 62d.

<5. Fifth Embodiment>

Still another example of the present invention will be described with reference to the drawings. Fig. 15 is a sectional view of still another example of the motor of the present invention. The motor E of this embodiment has the same structure as the motor D of the fourth embodiment except that the resin case 2e, the first cover member 3ea, and the second cover member 3eb are different. Therefore, in the structure of the motor E, the parts that are substantially the same as those of the motor D are denoted by the same reference numerals, and detailed description of the same parts will be omitted. In addition, in the motor E, the first bearing 51 is housed in a first bearing housing member 61 having the same structure as the motor A. As shown in FIG.

As shown in FIG. 15 , the resin case 2 e of the motor E has a stepped portion 25 e protruding radially outward from a portion of the outer peripheral surface closer to the second direction Or than the press-fit portion 22 . In addition, although the position of the axial direction of the step part 25e differs from the step part 25 which the motor B shown to FIG. 8, FIG. 9 has, it has the same shape and has the same purpose. That is, the resin case 2e has four stepped portions 25e, and these four stepped portions 25e are arranged at equal intervals in the circumferential direction. In addition, a first bearing housing member 61 is fixed to an end portion on the Op side in the first direction of the resin case 2e. In addition, the fixing method of the 1st bearing housing member 61 is the same as that of the resin case 2 of the motor A, and detailed description is abbreviate|omitted.

The first cover member 3ea has a bottomed cylindrical shape in which an end portion on the Op side in the first direction is closed. Furthermore, similarly to the cover 3 , the case contact portion 31 and the conductive portion 312 are provided at the bottom. Moreover, the 1st cover member 3ea has the 1st flange 32 which has the same structure as the 1st cover member 3da.

The second cover member 3eb is a cylindrical member extending in the axial direction. The second cover member 3eb and the second bearing housing member 62d are formed of the same member. Moreover, the 2nd bearing accommodation member 62d is continuously formed in the end part of the 2nd direction Or side of the 2nd cover member 3eb. In addition, the second cover member 3eb has a second flange 33e and a contact portion 35e extending radially outward at an end portion on the Op side in the first direction. The 2nd flange 33e is provided in the position which contacts the 1st flange 32 of the 1st cover member 3ea when covering the 2nd cover member 3eb from the 2nd direction Or side of the resin case 2e. Moreover, the contact part 35e is provided in the position which contacts the surface by the side of the 2nd direction Or of the step part 25e when covering the 2nd cover member 3eb from the side of the 2nd direction Or of the resin case 2e.

As shown in FIG. 15, in the 2nd cover member 3eb, the 2nd flange 33e is arrange|positioned rather than the contact part 35e on the side of the 1st direction Op. And the 2nd flange 33e and the contact part 35e are arrange|positioned alternately along the circumferential direction.

When the resin case 2 is press-fitted into the first cover member 3da, the first flange 32 comes into contact with the surface on the first direction Op side of the step portion 25e. And the 2nd cover member 3eb covers the 2nd direction Or side of the resin case 2e. At this time, the contact portion 35e of the second cover member 3eb is in contact with the second direction Or side end surface of the stepped portion 25e of the resin case 2e, and the second flange 33e is in contact with the first flange 32 .

In this way, since the resin case 2e has the stepped portion 25e, positioning in the axial direction at the time of press-fitting into the first cover member 3da is facilitated. Likewise, the axial positioning of the second cover member 3eb with respect to the resin case 2e is facilitated. For example, if the usage period of the motor E is prolonged, the outer diameter of the press-fit portion 22 may become smaller due to a change over time in the resin constituting the resin case 2e. At this time, the fixation of the resin case 2e with respect to the 1st cover member 2da by press fitting becomes weak. In the case of the motor E, the stepped portion 25e is also fixed at the mounting position together with the first flange 32 and the contact portion 35e. Therefore, even if the fixation by press fitting becomes weak, movement of the resin case 2e can be restricted. Thereby, even if it is used for a long period of time, performance degradation of the motor E can be suppressed.

In the motor E, the first flange 32 is in direct contact with the second flange 33e. Thus, the first cover member 3ea is in direct contact with the second cover member 3eb, the first cover member 3ea is electrically connected to the first bearing housing member 61, and the second cover member 3eb is made of the same member as the second bearing housing member 62d. form. As a result, the first bearing housing member 61 and the second bearing housing member 62 are brought into an indirect conduction state.

Other features are the same as those of the fourth embodiment.

<6. Sixth Embodiment>

Still another example of the present invention will be described with reference to the drawings. Fig. 16 is a sectional view of still another example of the motor of the present invention. The motor F of the present embodiment has the same configuration as the motor A of the first embodiment except for the connection portion 36 . Therefore, in the structure of the motor F, the parts that are substantially the same as those of the motor A are denoted by the same reference numerals, and detailed description of the same parts will be omitted.

As shown in FIG. 16 , the end portion on the second direction Or side of the cover 3 of the motor F is separated from the second bearing housing member 62 . Furthermore, it has the connection part 36 which electrically conducts between the cover 3 and the 2nd bearing housing member 62. As shown in FIG. The connection portion 35 has conductivity, and here, the connection portion 35 is made of metal. In addition, the connecting portion 36 has a step that is fitted between the cover 3 and the second bearing housing member 62 . By attaching the connecting portion 36 , the first bearing housing member 61 and the second bearing housing member 62 are electrically connected via the cover 3 and the connecting portion 36 . Accordingly, in the motor F, electrical corrosion of the first bearing 51 and the second bearing 52 is suppressed. In addition, by adopting a structure in which the cover 3 and the second bearing housing member 62 are connected via the connection portion 36 , the cover 3 and the second bearing housing member 62 can be electrically connected even if the axial length of the cover 3 varies.

Other features are the same as those of the fifth embodiment.

In addition, the connection portion 36 of the present embodiment has an annular shape having a discontinuous portion in a part of the circumferential direction. By adopting such a structure, the discontinuous part can be opened and attached to the cover 3 and the second bearing accommodating member 62 . The fixing of the connection part 36 can also be performed by gripping the cover 3, the 2nd bearing accommodation member 62, and the resin case 2 by its own elastic force. In addition, fixing methods such as screw fastening, bonding, welding, and welding may also be used.

The embodiments of the present invention have been described above, but the embodiments can be modified in various ways within the scope of the gist of the present invention.

Industrial availability

The present invention can be used as a motor for driving air conditioners, electric fans and the like.

Label description

A: motor; A1: motor; A2: motor; A3: motor; A4: motor; B: motor; C: motor; D: motor; E: motor; F: motor; 1: stator; 11: stator core; 111: core back; 112: teeth; 12: insulator; 120: wiring; 121: insulator teeth; 122: insulator core back; 13: winding; 130: bonding wire; 2: resin shell; 20 : Resin shell hole; 200: Groove; 201: Groove; 2011: Groove; 2012: Groove; 202: Hole; 21: Concave hole; 22: Press-fit part; 23: Recess; ;25: step part; 25e: step part; 3: cover; 3b: cover; 3c: cover; 3da: first cover part; 3db: second cover part; 3ea: first cover part; 3eb: second cover part ;30: cover hole; 31: shell contact portion; 310: through portion; 311: contact portion; 3111: extension portion; 312: conductive portion; 313: conductive portion; 314: conductive portion; 32: first flange; 33: second flange; 33e: second flange; 4: rotor; 40: rotating shaft; 411: cylindrical member; 412: shaft support member; 400: groove; 401: shaft retaining ring; 402: shaft retaining ring ;42: magnet; 43: molding part; 51: first bearing; 52: second bearing; 61: first bearing receiving part; 61d: first bearing receiving part; : Bearing flange; 612: Cylindrical press-fit part; 62: Second bearing storage part; 62d: Second bearing storage part; 620: Outer cylinder; 621: Storage part; 71: Bearing side intrusion prevention part; 71d: Bearing Side intrusion prevention member; 72: shaft side intrusion prevention member 72; Bd: substrate; Is: protective sheet.

Claims (10)

1. a kind of motor, includes

Rotor has the rotary shaft extended along central axis；

Stator, has multiple windings across insulator on stator core, and the stator core is outer with the rotor Circumferential surface is opposed radially；

Resin enclosure seals at least described insulator and the winding of the stator；

Multiple bearings, the rotation is being pivotally supported along the position that axial direction is separated from each other can to rotate by they；And

Cover covers the resin enclosure,

The stator has the multiple bearing storage members stored respectively to the multiple bearing,

The bearing storage member and the cover are the components of electric conductivity,

The cover directly or indirectly conducts respectively with the multiple bearing storage member.

2. motor according to claim 1, wherein

The motor has the conductive part for conducting the bearing storage member and the cover.

3. motor according to claim 1 or 2, wherein

In at least one turning part with the cover of the bearing storage member, the cover and the bearing storage member In a side be pressed into another party.

4. according to claim 1 to motor described in any one in 3, wherein

At least one party in the cover and the bearing incorporating section has the extension for axially extending and contacting with another party.

5. according to claim 1 to motor described in any one in 4, wherein

At least one of the bearing incorporating section is formed with the cover by the same part.

6. according to claim 1 to motor described in any one in 5, wherein

The cover is in the tubular axially extended,

The resin enclosure has the press-in portion for the inside for being pressed into the cover.

7. motor according to claim 6, wherein

When radially observing the resin enclosure, the press-in portion is Chong Die with the stator core.

8. motor according to claim 6 or 7, wherein

The internal diameter of the cover towards the resin enclosure pressing direction and gradually become smaller.

9. motor according to claim 6 or 7, wherein

The internal diameter of the cover towards the resin enclosure pressing direction and become smaller stage by stage.

10. according to claim 1 to motor described in any one in 9, wherein

The cover includes

1st cover member covers the resin enclosure from axial side；And

2nd cover member covers the resin enclosure from the axial other side,

1st cover member has the 1st flange extended from periphery towards radial outside,

2nd cover member has the 2nd flange extended from periphery towards radial outside,

1st cover member and the 2nd cover member make the 1st flange and the described 2nd convex when covering the resin enclosure Edge direct or indirect connection.