CN110476332B - Motor - Google Patents

Abstract

The motor has: a rotor; a stator; a resin case sealing at least the insulator and the winding of the stator; and a cover covering the resin case. The cover covers at least one of the resin housing on the radial outer side of the insulator and the axial one side of the insulator. At least a part of at least one of the radial outer side of the insulator and the axial one side of the insulator has a gap between the cover and the resin case.

Description

Motor

Technical Field

The present invention relates to a motor.

Background

A conventional brushless DC motor is disclosed in japanese laid-open patent publication H09-261935. The brushless DC motor described in japanese laid-open patent publication H09-261935 has a rotor and a stator. The stator has: an annular stator core that forms a rotating magnetic field with the rotor; and a stator winding wound around the stator core. Further, the structure is as follows: the stator is molded integrally with a housing made of resin, and an outer surface of the housing is covered with a protective cover made of metal.

The brushless DC motor radiates heat generated by the stator winding to the outside through the case made of resin, and prevents the case from being damaged by an external impact by covering the outer surface of the case with the protective cover made of metal.

In the motor disclosed in japanese patent laid-open No. H09-261935, the case is made of resin, and the protective cover is made of metal, so that there is a difference in expansion due to heat. Further, when the case covered with the protective cover expands greatly due to heat, the protective cover deforms due to the expansion, or pressure is applied to the internal devices, which may destabilize the operation.

Disclosure of Invention

Accordingly, an object of the present invention is to provide a motor that can be stably driven regardless of heat generated during driving.

The motor according to an exemplary embodiment of the present application is characterized by having a rotor, a stator, a resin case, and a cover. The rotor has a rotational axis extending along a central axis. The stator has a stator core, an insulator, and a plurality of windings. The stator core is opposed to the outer peripheral surface of the rotor in the radial direction. The insulator covers the stator core. The winding is wound around the stator core with an insulator interposed therebetween. The resin housing seals at least the insulator and the windings of the stator. The cover covers at least one of the resin housing on the radial outer side of the insulator and the axial one side of the insulator. At least a part of at least one of the radial outer side of the insulator and the axial one side of the insulator has a gap between the cover and the resin case.

According to the motor of the illustrated embodiment of the present application, the motor can be stably driven regardless of heat generated during driving.

Drawings

Fig. 1 is an exploded perspective view of an example of a 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 the stator.

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

Fig. 5 is a perspective view of the rotor.

Fig. 6 is a partial sectional view showing a resin case and a cover of a modified example of the motor of embodiment 1.

Fig. 7 is a partial sectional view showing a resin case and a cover of another modification of the motor of embodiment 1.

Fig. 8 is an exploded perspective view of another example of the motor of the present invention.

Fig. 9 is a sectional view of the motor shown in fig. 8.

Fig. 10 is a sectional view of another example of the motor of the present invention.

Fig. 11 is an exploded perspective view of another example of the motor of the present invention.

Fig. 12 is a sectional view of the motor shown in fig. 11.

Fig. 13 is a partial sectional view showing a resin case and a cover of a modification of the motor of embodiment 4.

Fig. 14 is a partial sectional view showing a resin case and a cover of another modification of the motor of embodiment 4.

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

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

Detailed Description

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

< 1. embodiment 1 > (ii)

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

In the present specification, the axial direction is set as follows with reference to fig. 2. That is, in fig. 2, the direction toward the axial right side is the 1 st direction Op, and the direction toward the left side is the 2 nd direction Or. In the present specification, "left direction" and "right direction" are set for the purpose of description. Therefore, these directions are not limited to the directions in which the motor a is actually used.

< 1.1 Structure of Motor >

As shown in fig. 1, a motor a of the present embodiment includes a stator 1, a resin case 2, a cover 3, a rotor 4, a1 st bearing 51, and a2 nd 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 the resin case 2. The rotor 4 is disposed inside the stator 1. The rotor 4 has a rotary shaft 40 extending along the central axis Ax. The rotary shaft 40 is supported by the 1 st bearing 51 and the 2 nd bearing 52 and is rotatable with respect 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.

< 1.2 stator Structure >

The stator 1 is explained with reference to the new drawings. Fig. 3 is a perspective view of the stator. Fig. 4 is a perspective view of a stator core included in the stator. As shown in fig. 3 and 4, the stator 1 includes a stator core 11, an insulator 12, and a winding 13. The stator 1 has a plurality of windings 13 wound around a stator core 11 with an insulator 12 interposed therebetween, and the stator core 11 is radially opposed to the outer peripheral surface of the rotor 4. As shown in fig. 2, the stator 1 includes a1 st bearing housing member 61 that houses the 1 st bearing 51 and a2 nd bearing housing member 62 that houses the 2 nd bearing 52.

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

The insulator 12 covers the stator core 11. The insulator 12 is a resin molded body. The insulator 12 covers the entire tooth portion 112 and covers both end faces in the axial direction of the core back 111. The wire is wound around the tooth portion 112 covered with the insulator 12 to form the winding 13. That is, the insulator 12 has: insulator teeth 121 covering teeth 112; and an insulator core back 122 covering at least an axial end portion of the core back 111. The stator core 11 is insulated from the winding 13 by an insulator 12. In the present embodiment, the insulator 12 is a resin molded body, but is not limited thereto. A structure capable of insulating stator core 11 from winding 13 can be widely employed.

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

The windings 13 are disposed in the respective teeth 112 of the stator core 11. That is, in the motor a, 12 windings 13 are arranged. The 12 windings 13 of the stator 1 are divided into 3 systems (hereinafter, referred to as three phases) according to the timing of supplying the current. The three phases are referred to as U-phase, V-phase, and W-phase, respectively. That is, the stator 1 has 4U-phase windings, 4V-phase windings, and 4W-phase windings. In the following description, the windings of the respective phases are collectively referred to as the windings 13.

The stator 1 includes a crossover 131, and the crossover 131 connects the plurality of windings 13 to each other or electrically connects the windings 13 to a control circuit (not shown) mounted on a substrate Bd provided in the motor a. That is, the plurality of windings 13 are electrically connected via the bridge wire portion 131. The crossover portion 131 is disposed in the wiring portion 120 of the insulator core back portion 122, and the insulator core back portion 122 covers the axial end face of the core back portion 111 of the insulator 12. That is, the insulator 12 has a wiring portion 120, and the wiring portion 120 is wired by the crossover portion 131. As shown in fig. 2, the stator 1 has a wiring portion 120 on which a wiring portion 131 is arranged on a surface on the radially outer side of the insulator 12 covering the end surface of the core back 111 on the 1 st direction Op side. That is, the wiring portion 120 extends from the axial end portion of the insulator core back portion 122 toward the axial direction (the 1 st direction Op side), and the crossover portion 131 is wired on the radially outer side surface of the wiring portion 120. The concave portion 23 is located on the outer peripheral surface of the resin case 2.

< 1.3 Structure of resin case and cover >

As shown in fig. 1, 2, and the like, the resin case 2 has a cylindrical shape. The resin case 2 is a molded body of resin that seals the stator core 11 inside. That is, the resin case 2 seals at least the insulator 12 and the winding 13 of the stator 1. As shown in fig. 2, the motor a also covers the outer surface of the stator core 11 in the radial direction. The resin case 2 has a bottomed cylindrical shape in which at least a part of an end portion on the 1 st direction Op side is closed. Further, a resin housing hole 20 extending in the axial direction is provided in a radially central portion of the bottom portion.

A concave hole 21 recessed in the axial direction is provided radially outside the resin case hole 20 on the surface on the 1 st direction Op side of the bottom portion. A rotary shaft 40 attached to the rotor 4 axially penetrates the resin housing hole 20. Further, a part of a bearing flange 611, which will be described later, of the 1 st bearing housing member 61 is fixed to the resin housing hole 20 by insert molding. The details of the 1 st bearing housing member 61 will be described later.

As shown in fig. 1, 2, and the like, the cover 3 covers the resin case 2. The cover 3 has a bottomed cylindrical shape in which at least a part of an end portion on the 1 st direction Op side is closed. That is, the cover 3 has a cylindrical shape extending in the axial direction. The cover 3 is formed by, for example, pressing a metal plate. That is, the cover 3 covers the resin housing 2 on at least one of the radial outside of the insulator 12 and the one axial side (the 1 st direction Op side) of the insulator 12. A radially central portion of the bottom of the cover 3 has a cover hole 30 penetrating in the axial direction. Further, a housing contact portion 31 that projects inward in the axial direction (the 2 nd direction Or side in fig. 2) is provided radially outward of the cover hole 30. That is, the cover 3 has a case contact portion 31 protruding inward at the radial center portion of the bottom portion, and a cover hole 30 at the center of the case contact portion 31.

The resin case 2 is inserted into the cover 3 in the 1 st direction Op side in fig. 2. The press-fit portion 22 described later is press-fitted into the cover 3. When the resin housing 2 is press-fitted into the cover 3, the housing contact portion 31 overlaps with the concave hole 21 in the axial direction. The resin case hole 20 and the cover hole 30 also overlap in the axial direction. The rotary shaft 40 penetrates the resin housing hole 20 and the cover hole 30.

When the resin case 2 is press-fitted into the cover 3, the case contact portion 31 contacts the concave hole 21. The case contact portion 31 presses the concave hole 21 to bring the resin case 2 into close contact with the cover 3. This suppresses entry of gas, water, dust, dirt, and the like from the boundary portion between the resin case 2 and the cover 3 from the boundary portion between the resin case hole 20 and the cover hole 30.

Next, the mounting of the resin case 2 to the cover 3 will be described. The resin case 2 has a press-fitting portion 22 and a recess 23 on the outer circumferential surface in the radial direction. That is, the resin case 2 has a press-fitting portion 22 press-fitted into the cover 3. As shown in fig. 2, the press-fitting portion 22 is disposed in a portion of the outer peripheral surface of the resin case 2 that overlaps 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 11. The resin case 2 is inserted into the opening of the cover 3 from the end on the side where the recess 23 is formed. Then, the resin case 2 is fixed to the cover 3 by press fitting. In the resin case 2 of the present embodiment, the recess 23 is provided so as to be offset in the axial direction with respect to the stator core 11, but may be partially overlapped.

That is, the resin case 2 is press-fitted to the inner peripheral surface of the cover 3 in the press-fitting portion 22. The press-fitting portion 22 is arranged at a position radially overlapping the stator core 11. At the time of press-fitting, a force acts on the resin housing 2 from the cover 3 in the radial direction and the axial direction. Since the press-fitting portion 22 is disposed at a position overlapping the stator core 11 in the radial direction, the resin case 2 is less likely to be deformed even if a force acts from the cover 3 at the time of press-fitting, and the strength of the stator core 11 is higher than that of the resin case 2.

The recess 23 radially overlaps the wiring portion 120, and the wiring portion 120 is provided with a crossover 131 of the insulator 12 on the outer peripheral surface of the resin case 2. That is, the gap Gp is located radially outward of the wiring portion 120. The outer peripheral surface of the resin case 2 has a recess 23 in a portion contacting the gap Gp. The recess 23 is provided at the end portion on the 1 st direction Op side of the resin housing 2, and is formed continuously in the circumferential direction. In the present embodiment, the resin case 2 is formed at a radial end portion thereof, but is not limited thereto.

Depending on the conditions (temperature, humidity, etc.) of the installation site of the motor a, water contained in the air inside the motor a may condense and accumulate as condensed water. Air is also accumulated in the concave portion 23, and moisture contained in the accumulated air is sometimes condensed. Therefore, a concave groove 200 extending from the concave portion 23 toward the 2 nd direction Or side is disposed on the outer peripheral surface of the resin housing 2. That is, the resin case 2 has a groove 200 extending from the gap Gp on the outer peripheral surface thereof. A drain hole 301 that connects the outside of the cover 3 to the recessed groove 200 is disposed in a position of the cover 3 that is continuous with the recessed groove 200.

Thereby, the condensed water accumulated in the concave portion 23 passes through the concave 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 not easily affected by the generation of condensed water 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 is evaporated in the air of the recess 23 by the heat at the time of driving the motor a.

The resin case 2 is inserted into the cover 3 from the side where the recess 23 is provided 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 recess 23 is formed and the inner surface of the cover 3. The gap Gp between the resin case 2 and the cover 3 will be described in detail later

As shown in fig. 2, the thickness of the portion of the resin case 2 having the recess 23 in the radial direction is thinner than the thickness of the other portions of the resin case 2. That is, the portion provided with the recess 23 is a thin portion 24 having a thickness thinner than the other portions. An electric current may flow through the crossover 131, thereby heating the crossover 131. At this time, the thin portion 24 facilitates heat release from the bonding wire portion 131 to the outside of the resin case 2.

< 1.4 Structure of rotor

Fig. 5 is a perspective view of the rotor. As shown in fig. 5, the rotor 4 includes a rotor core 41, a plurality of magnets 42, and a mold portion 43. The rotor core 41 includes: a cylindrical member 411 extending in the axial direction; and a shaft support member 412 disposed radially inward of the cylindrical member. The cylindrical member 411 and the shaft support member 412 are fixed to each other by a molded portion 43 which is a molded body of resin. The rotor core 41 is a magnetic body. The rotor core 41 may be a laminate in which magnetic plates are laminated in the radial direction, or may be a molded body formed of sintered powder into the same component.

The rotating shaft 40 has a cylindrical shape. The rotary shaft 40 penetrates a radially central portion of the shaft support member 412 of the rotor core 41. The rotary shaft 40 and the shaft support member 412 are relatively fixed. Examples of the fixing method include press fitting, welding, and the like, but are not limited thereto. A method of fixing the rotary shaft 40 and the shaft support member 412 can be widely adopted. That is, the rotary shaft 40 is fixed to the rotor 4, and the rotary shaft 40 is rotated around the center axis Ax by rotating the rotor 4.

The plurality of magnets 42 are disposed radially outward of the rotor core 41. In the rotor 4 of the present embodiment, a plurality of magnets 42 are arranged in a circumferential direction. For example, the rotor core 41 has 8 magnets 42. In the present embodiment, a plurality of magnets 42 are arranged, but the present invention is not limited to this. For example, a magnet in which N-poles and S-poles are alternately magnetized in the circumferential direction may be used for a cylindrical magnetic body.

That is, the rotor core 41 has a plurality of 1 pair of magnetic poles, with the N pole and the S pole being the 1 pair of magnetic poles. The magnet 42 is fixed to the rotor core 41 by, for example, molding of resin or the like. The method of fixing magnet 42 is not limited to molding of resin, and a method of not or hardly exerting an adverse effect on the rotation of rotor 4, such as adhesion, welding, or mechanical fixing, may be employed.

< 1.5 Structure of bearing >

The rotary shaft 40 is press-fitted into the 1 st bearing 51 and the 2 nd bearing 52 at two axially separated locations. That is, the rotary shaft 40 is rotatably supported by two axially different portions of the 1 st bearing 51 and the 2 nd bearing 52. An end of the rotation shaft 40 on the 2 nd direction Or side is press-fitted into an inner ring of the 2 nd bearing 52. A portion on the 1 st direction Op side of the portion of the rotation shaft 40 press-fitted into the 2 nd bearing 52 is press-fitted into the inner ring of the 1 st bearing 51.

The 1 st bearing 51 is accommodated in the 1 st bearing accommodating member 61. The 2 nd bearing 52 is housed in the 2 nd bearing housing member 62. The 1 st bearing housing member 61 and the 2 nd bearing housing member 62 are directly or indirectly fixed to the resin housing 2, and details will be described later. Thereby, the rotary shaft 40 is rotatably supported by the resin housing 2 (the covered stator 1) by 1 pair of bearings 51 and 52.

A shaft stopper 401 is attached to the rotating shaft 40 in the 1 st direction Op, and a shaft stopper 402 is attached to the end in the 2 nd direction Or. The shaft retainer 401 is in contact with the 1 st bearing 51. The shaft retainer 402 is in contact with the 2 nd bearing 52. The shaft retainer 401 and the shaft retainer 402 are fitted and fixed in a groove provided on the outer peripheral surface of the rotary shaft 40. The shaft stopper 401 contacts with the 2 nd direction Or side of the inner ring of the 1 st bearing 51. The movement of the rotary shaft 40 in the 1 st direction Op with respect to the 1 st bearing 51 is restricted by the retaining ring 401.

The shaft stopper 402 is in contact with the 1 st direction Op side of the inner race of the 2 nd bearing 52. The movement of the rotating shaft 40 in the 2 nd direction Or with respect to the 2 nd bearing 52 is restricted by the shaft stopper 402. The 1 st bearing 51 and the 2 nd bearing 52 are relatively restricted from moving in the axial direction of the stator 1, and thus the rotary shaft 40 is restricted from moving in the axial direction of the stator 1. For example, shaft retainers called C-ring and E-ring are generally used for the shaft retainers 401 and 402, but the present invention is not limited thereto. A structure that contacts the inner rings of each of the 1 pair of bearings 51, 52 to restrict the movement of the rotary shaft 40 can be widely adopted. In each of the embodiments described herein, the rotary shaft 40 is rotatably supported by two bearings (the 1 st bearing 51 and the 2 nd bearing 52), but the present invention is not limited to this. Or may be supported by more than 3 bearings.

< 1.6 Structure of bearing housing Member

Here, the 1 st bearing housing member 61 and the 2 nd bearing housing member 62 are made of metal such as iron or brass.

< 1.6.1 st bearing housing Member >

The 1 st bearing housing member 61 has a cylindrical shape capable of housing the 1 st bearing 51 therein. The 1 st bearing housing member 61 has an end surface portion 610 penetrating in the axial direction at a radially central portion at one axial end thereof. Further, the 1 st bearing housing member 61 has a bearing flange 611 extending radially outward at the other axial end thereof. At least a part of the bearing flange 611 is insert-molded to the resin housing 2. The 1 st bearing housing member 61 is fixed to the resin housing 2 by insert molding. The bearing flange 611 may be provided with a through portion that penetrates in the axial direction. By filling the through-hole portion with resin at the time of insert molding, the 1 st bearing housing member 61 is restricted from moving in the circumferential direction, i.e., from being stopped from rotating.

Further, if the rotation stop is reliably performed by the resin, the through portion is not limited to the hole, and may be, for example, a concave portion that is concave inward in the radial direction or a convex portion that protrudes outward in the radial direction. The rotation stop may be performed by making the bearing flange 611 itself have a polygonal shape (e.g., a triangular shape or a rectangular shape), or making the bearing flange 611 itself have an elliptical shape. The 1 st bearing housing member 61 is fixed to the resin case 2 such 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 1 st bearing 51 is press-fitted into the 1 st bearing housing member 61.

< 1.6.2 nd 2 nd bearing housing part >

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

The outer tube 620 has a larger diameter than the receiving portion 621, and the end of the cover 3 on the 2 nd direction Or side is press-fitted into the outer tube 620. The portion of the end of the cover 3 on the 2 nd direction Or side that is press-fitted into the outer cylindrical portion 620 is a cover press-fitting portion 300.

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

As shown in fig. 2, the housing portion 621 and the outer tube portion 620 are formed of the same member. Here, the 2 nd bearing housing member 62 is manufactured by rolling a metal plate. However, the present invention is not limited thereto.

< 1.7 other structural part >

As shown in fig. 2, in the motor a, the 2 nd direction Or side of the cover 3 is pressed into the outer cylinder 620 of the 2 nd bearing housing member 62. Therefore, foreign substances such as water, dust, and dirt are prevented from entering through the gap between the outer cylinder 620 and the cover press-fitting portion 300. On the other hand, the motor a has a bearing housing hole for the rotation shaft 40 to pass through on the 1 st direction Op side, and the bearing housing hole is disposed in the end surface portion 610 of the 1 st bearing housing member 61. The bearing housing hole is sized to form a gap with the rotating shaft 40 so as not to interfere with the rotation of the rotating shaft 40. Foreign matter such as water, dust, and dirt easily enters the motor a through the gap. Therefore, the motor a includes the bearing-side intrusion prevention member 71 and the shaft-side intrusion prevention member 72 for suppressing intrusion of foreign matters from the 1 st bearing housing member 61.

As shown in fig. 2, the bearing-side intrusion prevention member 71 covers the outer surface of the 1 st bearing housing member 61. And surrounds the outer side of the rotating shaft 40 and extends in the radial direction. The bearing-side intrusion prevention member 71 is made of a material such as rubber, and is in close contact with the 1 st bearing housing member 61. The bearing-side intrusion prevention member 71 is attached to the rotary shaft 40 with a gap therebetween, i.e., so as to maintain non-contact therewith.

The shaft-side intrusion prevention member 72 is disposed so as to surround the radial outside of the bearing-side intrusion prevention member 71. The shaft-side intrusion prevention member 72 is disposed in a groove 400 provided in the rotary shaft 40. This restricts the axial movement of the shaft-side intrusion prevention member 72. The entry of foreign matter into the motor a is suppressed by reducing the space between the bearing-side entry prevention member 71 and the shaft-side entry prevention member 72. That is, the bearing-side intrusion prevention member 71 and the shaft-side intrusion prevention member 72 are attached to the motor a at the same time, thereby suppressing entry of foreign matter into the motor a.

A part of the tip of the shaft-side intrusion prevention member 72 on the 2 nd direction Or side overlaps the concave hole 21. 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 rotary shaft 40 in a state of not contacting the housing contact portion 31. That is, a part of the opening of the shaft-side intrusion prevention member 72 is disposed in the concave hole 21. Further, since the housing contact portion 31 and the shaft-side intrusion prevention member 72 are not in contact with each other, the rotation of the rotary shaft 40 is not restricted.

The resin case 2 has a substrate Bd and a protective sheet Is on the 2 nd direction Or side of the stator 1. The board Bd is mounted with a control circuit (not shown) for controlling the timing of the current supplied to the plurality of windings 13, the magnitude of the current, and the like. In addition, the control circuit may be provided outside the motor a, and in this case, the substrate Bd may be omitted. The protective sheet Is an insulating member disposed between the substrate Bd and the 2 nd bearing housing member 62. In the case of using a motor without the substrate Bd, the protective sheet Is may be omitted.

< 1.8 actions of Motor >

The operation of the motor a described above will be described. When the motor a is driven, a current is supplied to the winding 13. At this time, the coil 13 generates heat by the current. At this time, the stator core 11 is also heated by the heat of the winding 13. The stator core 11 and the windings 13 are covered with a resin case 2. The heat of the stator core 11 and the windings 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 a metal material and has a smaller linear expansion coefficient than the resin case 2. This causes a difference in the amount of deformation of the resin case 2 and the cover 3 due to thermal expansion. However, the resin case 2 and the cover 3 are press-fitted into the press-fitting portion 22 of the resin case 2. Therefore, the heat of the resin case 2 is transferred to the cover 3 and radiated, and therefore, the thermal expansion of the resin case 2 is suppressed in the press-fitting portion 22.

In the resin case 2, the insulator 12 is sealed by the resin case 2 at a portion displaced in the axial direction from the press-fitting portion 22. The insulator 12 is resin, and the linear expansion coefficient 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 is more deformed outward in the radial direction by thermal expansion than the press-fit portion 22 that overlaps the stator core 11 in the radial direction. Further, since the distance between the stator core 11 and the cover 3 is larger, the heat dissipation is inferior to that of the press-fit portion 22. Therefore, a difference in the amount of deformation due to thermal expansion between the insulator 12 and the cover 3 causes problems such as strain and displacement of the resin case 2.

In addition, with respect to the opening side (2 nd direction Or side in fig. 2) of the cover 3 of the resin housing 2, deformation of the resin housing 2 due to thermal expansion is released to the opening side. On the other hand, the back side of the cover 3 (the 1 st direction Op side in fig. 2) has no portion for releasing the deformation due to thermal expansion. Therefore, in the motor a, a gap Gp is provided between the cover 3 and the resin case 2 radially outward of the insulator 12.

Thereby, the difference in the amount of deformation between the resin case 2 and the cover 3 at a position (particularly, the back side in the press-fitting direction) of the resin case 2 that is offset from the stator core 11 in the axial direction is absorbed by the gap Gp. This can suppress defects such as strain and displacement of the resin case 2 due to a difference in deformation amount between the resin case 2 and the cover 3 due to thermal expansion.

According to the motor a of the present embodiment, a gap is provided between the resin case 2 and the cover 3 at a portion where the difference in the amount of deformation due to heat is large. The gap Gp absorbs the difference in the amount of thermal deformation between the resin case 2 and the cover 3, and thus strain, displacement, and the like caused by the difference in the amount of thermal deformation can be suppressed. Further, by forming the recess 23 in the resin case 2, a gap between the resin case 2 and the cover 3 can be easily formed. The portion of the resin case 2 having the recess 23, that is, the portion overlapping the recess 23 in the radial direction in fig. 2 is a thin portion 24 thinner than the other portion of the resin case 2. By providing the thin portion 24 in this way, heat generated when current flows through the crossover 131 is easily discharged to the outside of the resin case 2.

< 1.9 modification >

< 1.9.1 modified example 1 >

A modified example of the motor shown in the present embodiment will be described with reference to the drawings. Fig. 6 is a partial 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, substantially the same parts are denoted by the same reference numerals, and detailed description of the same parts is omitted.

In the motor a1 shown in fig. 6, the diameter of the outer peripheral surface of the resin case 2a1 gradually decreases toward the back side in the press-fitting direction, that is, toward the 1 st 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 back side in the press-fitting direction. Further, the cover 3a1 has a shape into which the resin case 2a1 can be inserted. The cover 3a1 has a cylindrical shape, and the diameter thereof gradually decreases at least toward the back side in the press-fitting direction of the inner peripheral surface, i.e., toward the 1 st direction Op in fig. 6. That is, the inner diameter of the cover 3a1 gradually decreases toward the press-fitting direction of the resin case 2a 1. By changing the shapes of the resin case 2a1 and the cover 3a1, insertion is facilitated.

< 1.9.2 modified example 2 >

A modified example of the motor according to the present embodiment will be described with reference to the drawings. Fig. 7 is a partial sectional view showing a resin case and a cover of another modification 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, substantially the same parts are denoted by the same reference numerals, and detailed description of the same parts is omitted.

In the motor a2 shown in fig. 7, the diameter of the outer peripheral surface of the resin case 2a2 becomes smaller in stages toward the back side in the press-fitting direction, that is, toward the 1 st direction Op in fig. 7. That is, the outer peripheral surface of the resin case 2a2 has a plurality of different outer shapes. The outer peripheral surface of the resin case 2a2 is small in diameter on the back side in the press-fitting direction, and has a step at a portion where the outer shape changes. The cover 3a2 has a shape into which the resin case 2a2 can be inserted. The cover 3a2 is cylindrical, and has a diameter that gradually decreases at least on the back side of the inner peripheral surface in the press-fitting direction, i.e., on the 1 st direction Op side in fig. 7. That is, the inner diameter of the cover 3a2 gradually decreases toward the press-fitting direction of the resin case 2a 2.

By having the shapes of the resin case 2a2 and the cover 3a2, insertion becomes easy. In addition, by bringing the step of the resin housing 2a2 into contact with the step of the cover 3a2, positioning at the time of inserting the resin housing 2a2 into the cover 3a2 can be performed. Then, the press-fitting portion 222 of the resin case 2a2 comes into contact with the press-fitted portion of the cover 3a2 and starts press-fitting. This can reduce the force acting by press-fitting. The amount of deformation of the resin case 2a2 at the time of press-fitting can be reduced. This makes it easy to suppress the occurrence of strain or the like in the stator 1.

< embodiment 2 >

Another example of the motor of the present invention will be described with reference to the drawings. Fig. 8 is an exploded perspective view of another example of the motor of the present invention. Fig. 9 is a sectional view of the motor shown in fig. 8. As shown in fig. 8 and 9, the resin case 2B of the motor B has a step portion 25 extending radially outward on the 2 nd direction Or side. The resin case 2b has a plurality of (4 here) step portions 25. The step portions 25 are arranged at the same positions in the axial direction as the resin housing 2b at equal intervals in the circumferential direction. The cover 3b has an abutting portion 311 protruding outward from the outer peripheral surface. The contact portion 311 is configured such that, 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 abutting portion 311 contacts a surface of the stepped portion 25 in the press-fitting direction (the 1 st direction Op side in fig. 9).

Further, portions of the cover 3b between the abutting portions 311 adjacent in the circumferential direction extend to the opening side (the 2 nd direction Or side in fig. 9) than the abutting portions 311 in the axial direction. In the motor B of the present embodiment, the resin case 2B is directly press-fitted into the outer cylinder 620 of the 2 nd bearing housing member 62.

The step portion 25 is a convex portion for mounting the motor B to the equipment. Therefore, the step portion 25 has a mounting hole for inserting a fixing tool such as a screw. Further, the abutting portion 311 that is brought into contact with the step portion 25 formed of the same member as the resin case 2b is formed of the same member as the cover 3b having higher strength than the resin case 2 b. This enables the motor B to be firmly fixed. Further, even if vibration, impact, or the like acts, the motor B is not easily detached. The number and position of the step portions 25 are not limited to the above, and may be changed according to the shape and position of a mounting portion (not shown) of the device to which the motor B is mounted.

Other features are the same as those of embodiment 1.

< 3 > embodiment 3

Fig. 10 is a sectional view of another example of the motor of the present invention. In the motor C shown in fig. 10, the stator 1C and the resin case 2C are different from each other, but the rest is the same as the motor a of embodiment 1. 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 is omitted.

As shown in fig. 10, in the stator 1C of the motor C, an insulator core back portion 122 is provided at the end portion on the 1 st direction Op side of the insulator 12. The insulator core back 122 has a wiring portion 120c on which the bonding wire portion 131 is disposed. A recess 23c is formed in the resin case 2c at a position overlapping the wiring portion 120c in the axial direction. That is, the wiring portion 120c extends in the axial direction from the axial direction (1 st direction Op side) end portion of the insulator core back portion 122. The bridge wire portion 131 is wired on an axial end surface of the wiring portion 120c, and the recess 23c is located on an axial end surface of the resin case 2 c.

The portion of the recess 23c is a thin portion 24 c. That is, the gap Gp is located on one axial side (the 1 st direction Op side) of the wiring portion 120 c. Further, a gap Gp is provided between the covers 3c that overlap the recess 23c in the axial direction. That is, in the motor C, at least a part of the insulator 12 has a gap between the cover 3C and the resin case 2C on one side in the axial direction.

The press-fitting portion 22 of the resin case 2c is disposed on the outer peripheral surface. Therefore, when the resin case 2c is press-fitted into the cover 3c, a force at the time of press-fitting acts on the outer peripheral surface of the resin case 2 c. In the motor C, the recess 23 is disposed at the end portion on the 1 st direction Op side in the axial direction, and thus the force at the time of press-in is not easily concentrated on the recess 23C. This can suppress deformation such as strain in the concave portion 23c and the vicinity thereof, and suppress displacement of the resin case 2c with respect to the cover 3 c. Although not shown, the resin case 2c may have a groove extending from the gap Gp on the outer peripheral surface thereof.

Other features are the same as those of embodiment 1.

< 4 > embodiment 4

Still another embodiment of the present invention will be described with reference to the drawings. Fig. 11 is an exploded perspective view of another example of the motor of the present invention. Fig. 12 is a sectional view of the motor shown in fig. 11. The motor D of the present embodiment has the same configuration as the motor a of embodiment 1, except that the cover, the 1 st bearing housing member 61D, the 2 nd bearing housing member 62D, and the bearing-side intrusion prevention member 71D are different. Therefore, in the structure of the motor D, the same reference numerals are given to the same parts as those of the motor a, and detailed description of the same parts is omitted.

< 4.1 cover >

As shown in fig. 11 and 12, the housing of the motor D has a1 st housing part 3da and a2 nd housing part 3 db. Namely, the cover has: a1 st cover member 3da covering the resin housing 2 from one side (the 1 st direction Op side) in the axial direction; and a2 nd cover member 3db covering the resin housing 2 from the other side (the 2 nd direction Or side) in the axial direction. The 1 st cover member 3da is pressed into the resin case 2 in the 1 st direction Op. Further, the 2 nd direction Or side of the resin housing 2 is inserted into the 2 nd cover member 3 db. In the motor D of the present embodiment, the 1 st direction Op side of the resin case 2 is press-fitted to the 1 st cover member 3da, but the present invention is not limited thereto. For example, the 2 nd direction Or side of the resin housing 2 may be press-fitted into the 2 nd cover member 3 db. Alternatively, both may be press-fitted. The cover member of the 1 st cover member 3da and the 2 nd cover member 3db to which the resin housing 2 is press-fitted is determined according to the position of the press-fitting portion 22 of the resin housing 2.

< 4.2 No. 1 cover part >

As shown in fig. 11 and 12, the 1 st cover member 3da has a bottomed cylindrical shape with the end portion on the 1 st direction Op side closed. The 1 st cover member 3da has a1 st flange 32 extending radially outward at the end on the 2 nd direction Or side. That is, the 1 st cover member 3da has the 1 st flange 32 extending radially outward from the outer peripheral surface. As shown in fig. 11, the 1 st flange 32 has a quadrangular shape (e.g., a square shape) when viewed in the axial direction. The 1 st flange 32 is shaped to be attachable to a mounting portion of a device (not shown) to which the motor D is mounted.

The radial center of the bottom of the 1 st cover member 3da and the 1 st bearing receiving member 61d are formed by the same member. That is, the rotating shaft 40 is rotatably supported by a plurality of bearings (51, 52), and the cover (1 st cover member 3da) holds at least one of the plurality of bearings (bearing 51). The 1 st bearing housing member 61d and the bearing-side intrusion prevention member 71d are formed of the same member. That is, the 1 st cover member 3da, the 1 st bearing housing member 61d, and the bearing-side intrusion prevention member 71d are formed of the same member. That is, the 1 st bearing receiving member 61d protrudes from the bottom of the 1 st cover member 3da in the 1 st direction Op. The bearing-side intrusion prevention member 71d protrudes from a radial center portion of the 1 st-direction Op-side end surface portion 610d of the 1 st bearing housing member 61d toward the 1 st direction Op. The bearing-side intrusion prevention member 71d is formed of the same metal as the 1 st bearing housing member 61 d.

The 1 st bearing housing member 61d is formed of the same member as the 1 st cover member 3da, and houses the 1 st bearing 51 therein, and functions in the same manner as the 1 st bearing housing member 61 of the motor a. The bearing-side intrusion prevention member 71d is made of a different material, but is used in combination with the shaft-side intrusion prevention member 72 to suppress the entry of foreign matter such as water, dust, and dirt, and functions similarly to the bearing-side intrusion prevention member 71 of the motor a.

< 4.3 No. 2 cover part >

As shown in fig. 11 and 12, the 2 nd cover member 3db is a cylindrical member extending in the axial direction. The 2 nd cover member 3db and the 2 nd bearing housing member 62d are formed of the same member. Further, a2 nd bearing housing member 62d is continuously formed at an end portion of the 2 nd direction Or side of the 2 nd cover member 3 db. The 2 nd cover member 3db has a2 nd flange 33 extending radially outward at an end portion on the 1 st direction Op side. That is, the 2 nd cover member 3db has the 2 nd flange 33 extending radially outward from the outer peripheral surface. As shown in fig. 11, the 2 nd flange 33 has a quadrangular shape (e.g., a square shape) when viewed in the axial direction. The 2 nd flange 33 has a shape overlapping with the 1 st flange 32 in the axial direction.

The 2 nd bearing housing member 62d has the same configuration as the 2 nd bearing housing member 62 used in the motor a except that the portion of the 2 nd bearing housing member 62 of the motor a present in the outer cylindrical portion 620 is the same as and continuous to the 2 nd cover member 3 db. That is, the 2 nd bearing housing member 62d has a housing portion 621d that houses the 2 nd bearing 52. The rotary shaft 40 is rotatably supported by a plurality of bearings (54, 52), and the cover (2 nd cover member 3db) holds at least one of the plurality of bearings (bearing 52).

< 4.4 Assembly of Motor >

The resin case 2 is inserted into the 1 st cover member 3da from the 1 st direction Op side, and the press-fitting portion 22 is press-fitted into the 1 st cover member 3 da. On the other hand, the 2 nd cover member 3db covers only the resin housing 2 without press-fitting. Therefore, the 2 nd cover member 3db into which the portion of the resin housing 2 on the 2 nd direction Or side is inserted may be rotatable about the central axis Ax. Therefore, the surface on the 1 st direction Op side of the 2 nd flange 33 has the projection 330 projecting in the 1 st direction Op. The protrusion 330 is inserted into the positioning hole 320, and the positioning hole 320 is disposed on the 1 st flange 32. Thereby, the circumferential positions of the 1 st flange 32 and the 2 nd flange 33, i.e., the 1 st cover member 3da and the 2 nd cover member 3db are adjusted.

The 1 st flange 32 and the 2 nd flange 33 fix the 1 st cover member 3da and the 2 nd cover member 3db to each other. Therefore, the 1 st flange 32 and the 2 nd flange 33 have screw fixing holes through which fixing tools (screws in this case) are inserted. Then, the 1 st flange 32 and the 2 nd flange 33 are fixed to each other, whereby the 1 st cover member 3da and the 2 nd cover member 3db are fixed to each other. That is, when the 1 st and 2 nd cover members 3da and 3db cover the resin housing 2, the 1 st and 2 nd flanges 32 and 33 are directly or indirectly connected.

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

That is, in the motor D, the rotating shaft 40 is supported by the 1 st bearing 51 and the 2 nd bearing 52, and the 1 st bearing 51 and the 2 nd bearing 52 are attached to the 1 st cover member 3da and the 2 nd cover member 3db to which the resin housing 2 is press-fitted. Thereby, the rotor 4 is supported rotatably inside the stator 1 at a predetermined interval in the radial direction.

In this way, the length of the press-fitting portion 22 to be press-fitted can be shortened by covering the resin housing 2 with the 1 st cover member 3da and the 2 nd cover member 3 db. This reduces the force acting on the resin case 2 and the cover, thereby suppressing deformation such as strain and displacement of the resin case 2 and the cover. Further, this enables the stator 1 and the rotor 4 to be accurately aligned, and thus, the performance of the motor D can be prevented from being degraded.

< 4.5 modification

< 4.5.1 modified example 1 >)

A modified example of the motor according to the present embodiment will be described with reference to the drawings. Fig. 13 is a partial sectional view showing a resin case and a cover of a modified example of the motor of the present embodiment. The motor D1 shown in fig. 13 has the same configuration as the motor D shown in fig. 11 and 12 except that the resin housing 2D1, the 1 st cover member 3da1, and the 2 nd cover member 3db1 are different. Therefore, substantially the same parts are denoted by the same reference numerals, and detailed description of the same parts is omitted.

In the motor D1 shown in fig. 13, the resin case 2D1 has a1 st step portion 25D1 and a2 nd step portion 25D2 on its outer peripheral surface. The 1 st step portion 25d1 is disposed on the 1 st direction Op side of the press-fitting portion 22. The 1 st step part 25d1 is a step depressed on the 1 st direction Op side. The 2 nd step portion 25d2 is disposed on the 2 nd direction Or side of the press-in portion 22. The 2 nd step portion 25d2 is a step recessed in the 2 nd direction Or side.

The 1 st cover member 3da1 has an abutting portion 34d at a position overlapping the step portion 25d1 of the resin housing 2d1 when the resin housing 2d1 is pressed into the interior. The abutting portion 34d has a shape obtained by cutting and bending an outer peripheral surface portion of a cylindrical shape. The abutting portion 34d is formed by bending the anterior side (the 2 nd direction Or side in fig. 13) in the press-fitting direction inward. Further, if the resin case 2d1 is press-fitted to a certain depth, the tip of the abutment portion 34d comes into contact with the step portion 25d 1. This determines the axial position of the resin case 2d1 when pressed into the 1 st cover member 3da 1.

The 2 nd cover member 3db1 has a contact portion 35d at a position overlapping the stepped portion 25d2 of the resin housing 2d1 when attached so as to cover the outer surface of the resin housing 2d1 in the 2 nd direction Or. The abutting portion 35d has a shape obtained by cutting and bending an outer peripheral surface portion of a cylindrical shape. The abutting portion 35d is formed by bending the back side in the press-fitting direction (the 1 st direction Op side in fig. 13) inward. Further, if the resin case 2d1 is inserted to a certain depth, the front end of the abutting portion 35d contacts the step portion 25d 2. Thereby, the axial position of the resin housing 2d1 at the time of insertion into the 2 nd cover member 3db1 is determined.

In the above-described embodiment, when the resin housing 2d1 is press-fitted into the 1 st cover member 3da1 and the resin housing 2d1 is inserted into the 2 nd cover member 3db1, it is possible to suppress the force exceeding the required press-fitting force from acting. This can suppress deformation of the resin case 2D1, the 1 st cover member 3da1, and the 2 nd cover member 3db1, and can suppress performance degradation of the motor D1.

< 4.5.2 modified example 2 >

Other modifications of the motor shown in the present embodiment will be described with reference to the drawings. Fig. 14 is a partial sectional view showing a resin case and a cover of another modification of the motor of the present embodiment. Fig. 14 is a cross-sectional view of the radial center of the 1 st direction end of the motor D2. The motor D2 shown in fig. 14 has the same configuration as the motor D shown in fig. 11 and 12 except that the resin housing 2, the 1 st cover member 3da2, and the 1 st bearing housing member 61 are different. Therefore, in the structure of the motor D2, 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 is omitted.

In a motor D2 shown in fig. 14, the resin case 2 and the 1 st bearing housing member 61 have the same configuration as the motor a of embodiment 1. That is, the 1 st bearing housing member 61 is disposed in the resin housing hole 20 of the resin housing 2, and the bearing flange 611 is insert-molded to the resin housing 2. The 1 st cover member 3da2 has a cover hole 30 at the end on the 1 st direction Op side, and the housing contact portion 31 presses the concave hole 21 of the resin housing 2. That is, the 1 st cover member 3da2 and the 1 st bearing housing member 61 are formed of different members. Thus, even when vibration or impact acts on the 1 st cover member 3da2, the 1 st bearing 51 is not or is not easily affected. This makes it difficult for the rotation of the motor D2 to be deviated by vibration or impact, and can suppress a decrease in the performance of the motor D2.

< 5. 5 th embodiment > (iii)

Still another embodiment of the present invention will be described with reference to the drawings. Fig. 15 is a sectional view of another example of the motor of the present invention. The motor E of the present embodiment has the same configuration as the motor D of embodiment 4, except that the resin housing 2E and the 2 nd cover member 3eb are different. Therefore, in the structure of the motor E, the same reference numerals are given to the same parts as those of the motor D, and detailed description of the same parts is omitted.

As shown in fig. 15, the resin case 2E of the motor E has a stepped portion 25E protruding radially outward at a position closer to the 2 nd direction Or than the press-fitting portion 22 of the outer peripheral surface. The axial position of the stepped portion 25e is different from that of the stepped portion 25 of the motor B shown in fig. 8 and 9, but has the same shape and the same purpose. That is, the resin case 2e has 4 step portions 25e, and the 4 step portions 25e are arranged at equal intervals in the circumferential direction.

The 1 st flange 32 of the 1 st cover member 3da contacts the surface of the step portion 25e on the 1 st direction Op side. The 2 nd cover member 3eb covers the resin case 2e in the 2 nd direction Or. The 2 nd cap component 3eb has: a2 nd flange 33e which is in contact with the 1 st flange 32 of the 1 st cover member 3 da; and an abutting portion 35e that contacts a surface of the stepped portion 25e on the 2 nd direction Or side. The 2 nd flange 33e and the abutment portion 35e extend radially outward. That is, the 2 nd flange 33e has the following structure: a part (4 locations in this case) in the circumferential direction has an abutting portion 35e extending radially outward from a position shifted toward the 2 nd direction Or side.

In this way, the resin housing 2e has the stepped portion 25e, so that the positioning in the axial direction when the resin housing is pushed into the 1 st cover member 3da is facilitated. Similarly, the axial positioning of the 2 nd cover member 3eb with respect to the resin housing 2e is facilitated. For example, if the motor E is used for a long period of time, the outer diameter of the press-fitting portion 22 may become smaller due to aged deterioration of the resin constituting the resin case 2E. At this time, the fixation of the resin case 2e to the 1 st cover member 2da by the press-fitting is weakened. In the case of the motor E, the step portion 25E is also fixed to the mounting position together with the 1 st flange 32 and the abutting portion 35E. Therefore, even if the fixation by press-fitting is weakened, the movement of the resin case 2e can be restricted. This can suppress a decrease in the performance of the motor E even when used for a long period of time.

Other features are the same as those of embodiment 4.

< 6. 6 th embodiment >

Still another embodiment of the present invention will be described with reference to the drawings. Fig. 16 is a sectional view of another example of the motor of the present invention. The motor F of the present embodiment has the same configuration as the motor D2 of the 2 nd modification example of embodiment 4, except that the resin housing 2e, the 2 nd cover member 3fb, and the 2 nd bearing housing member 62 are different.

As shown in fig. 16, the 2 nd cover member 3fb and the 2 nd bearing housing member 62 are separate members. The motor F fixes the 1 st flange 32 of the 1 st cover member 3da2 and the abutting portion 331F of the 2 nd cover member 3fb together at the mounting position. Accordingly, even if the mounting state of one of the 1 st cover member 3da2 and the 2 nd cover member 3fb becomes unstable, the other is fixed to the resin housing 2e, so that the operation of the motor F is not easily unstable. Further, since the 2 nd cover member 3fb and the 2 nd bearing housing member 62 are separate bodies, even when the mounting of the 2 nd cover member 3fb becomes unstable, the relative position of the 2 nd bearing housing member 62 and the resin housing 2e, that is, the 1 st bearing housing member 61 is not easily displaced. This enables the motor F to be stably rotated.

Other features are the same as those of embodiment 5.

While the embodiments of the present invention have been described above, the embodiments may be variously modified within the scope of the gist of the present invention.

The present invention can be used as a motor for driving an air conditioner, an electric fan, or the like.

Claims (11)

1. A motor has a rotor, a stator, a resin case, and a cover,

the rotor has a rotational axis extending along a central axis,

the stator has a stator core, an insulator, and a plurality of windings electrically connected via a crossover portion,

the stator core is opposed to the outer peripheral surface of the rotor in the radial direction,

the insulator covers the stator core and is provided with a plurality of insulating layers,

the winding is wound around the stator core with the insulator interposed therebetween,

the resin case seals at least the insulator and the winding of the stator,

it is characterized in that the preparation method is characterized in that,

the cover covers a radially outer side of the insulator and a resin case on one axial side of the insulator,

a thin portion having the thinnest thickness on at least one of a radial outer side of the insulator and an axial one side of the insulator has a gap between the cover and the resin case, the gap absorbing a difference in deformation amount due to thermal expansion between the resin case and the cover,

the insulator has a wiring portion for wiring the crossover wire portion, the gap provided in the thin portion is arranged at a position overlapping the wiring portion in a radial direction or an axial direction, the wiring portion, the thin portion, and the gap overlap in the radial direction or the axial direction, and heat of the crossover wire portion is discharged to the gap through the thin portion and discharged to the outside of the resin case.

2. The motor of claim 1,

the outer peripheral surface of the resin case has a recess at a portion in contact with the gap.

3. The motor of claim 2,

the stator core has:

an annular iron core back; and

a tooth portion extending radially inward from the core back portion,

the insulator has:

an insulator tooth portion covering the tooth portion; and

an insulator core back covering at least an axial end portion of the core back,

the wiring portion extends from an axial end portion of the insulator core back portion toward an axial direction,

the bonding wire portion is wired on the radially outer side surface of the wiring portion,

the recess is located on an outer peripheral surface of the resin case.

4. The motor of claim 2,

the stator core has:

an annular iron core back; and

a tooth portion extending radially inward from the core back portion,

the insulator has:

an insulator tooth portion covering the tooth portion; and

an insulator core back covering at least an axial end portion of the core back,

the wiring portion extends from an axial end portion of the insulator core back portion toward an axial direction,

the bonding wire portion is wired on an axial end face of the wiring portion,

the recess is located at an axial end face of the resin case.

5. The motor according to claim 3 or 4,

the resin case has a groove extending from the gap on an outer peripheral surface thereof.

6. The motor of claim 3 or 4,

the cover is in a cylindrical shape extending along the axial direction,

the resin case has a press-fitting portion that is press-fitted into the cover.

7. The motor of claim 6,

the press-fit portion overlaps with the stator core when the resin case is viewed in a radial direction.

8. The motor of claim 6,

the inner diameter of the cover is gradually reduced toward the press-fitting direction of the resin housing.

9. The motor of claim 6,

the inner diameter of the cover gradually decreases toward the press-fitting direction of the resin case.

10. The motor according to any one of claims 1 to 4,

the cover has:

a1 st cover member that covers the resin housing from one axial side; and

a2 nd cover member that covers the resin housing from the other axial side,

the 1 st cover member has a1 st flange extending radially outward from an outer peripheral surface,

the 2 nd cover member has a2 nd flange extending radially outward from an outer peripheral surface,

the 1 st cover member and the 2 nd cover member directly or indirectly connect the 1 st flange and the 2 nd flange when covering the resin housing.

11. The motor according to any one of claims 1 to 4,

the rotating shaft is rotatably supported by a plurality of bearings,

the cover holds at least one of the plurality of bearings.

Images