阅读说明：本技术 马达 (Motor ) 是由 斋藤裕也 藤原英雄 于 2020-08-26 设计创作，主要内容包括：提供马达,本发明的马达的一个方式具有：转子,其绕中心轴线旋转；定子,其在径向上与转子对置；壳体,其由树脂构成,埋入有定子；以及嵌件部件。嵌件部件具有：主体部,其埋入于壳体；以及被紧固部,其紧固有紧固部件。主体部和被紧固部由一个部件构成。(Provided is a motor, one embodiment of the motor of the present invention includes: a rotor that rotates about a central axis; a stator that is radially opposed to the rotor; a housing made of resin and having a stator embedded therein; and an insert component. The insert member has: a main body portion embedded in the housing; and a fastened portion to which the fastening member is fastened. The main body portion and the fastened portion are constituted by one member.)

1. A motor, comprising:

a rotor that rotates about a central axis;

a stator radially opposed to the rotor;

a housing made of resin and having the stator embedded therein; and

the parts of the insert are provided with a plurality of embedded parts,

the insert member has:

a main body portion embedded in the housing; and

a fastened portion to which a fastening member is fastened,

the main body portion and the fastened portion are constituted by one member.

2. The motor of claim 1,

a plurality of the fastened parts are arranged in a circumferential direction,

the insert member has a plurality of 1 st coupling portions extending radially outward from the main body portion and coupling the main body portion and the fastened portion.

3. The motor according to claim 1 or 2,

the insert member has a 4 th coupling portion that couples the fastened portions to each other.

4. The motor of claim 3,

the 4 th coupling part has an axial dimension that decreases between the pair of fastened parts as it goes away from the fastened parts, and is smallest at an intermediate position.

5. The motor according to claim 3 or 4,

the 4 th coupling part has a radial dimension that decreases between the pair of fastened parts as it goes away from the fastened parts, and is smallest at an intermediate position.

6. The motor according to any one of claims 3 to 5,

the 4 th connecting portion is annular with a central axis J as a center.

7. The motor of claim 2,

the insert member has a 2 nd coupling portion extending annularly around the central axis and cross-connected to the 1 st coupling portion.

8. The motor of claim 7,

the 1 st coupling part has an axial dimension larger than an axial dimension of the 2 nd coupling part.

9. The motor according to claim 7 or 8,

the insert member has a 3 rd coupling portion extending radially outward from the body portion and connected to the 2 nd coupling portion.

10. The motor of claim 9,

an axial dimension of the 1 st coupling part is larger than an axial dimension of the 3 rd coupling part.

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

the main body portion holds a bearing that rotatably supports the rotor.

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

the insert member has a through hole penetrating in the axial direction,

the housing has an entry portion that enters the through hole.

13. The motor according to any one of claims 1 to 12,

the fastened portion overlaps with the stator when viewed from the axial direction.

14. The motor according to any one of claims 1 to 13,

the fastened portion has:

an exposed end portion located on one side in an axial direction and exposed from the housing; and

a fastened hole which is open at the exposed end and into which the fastening member is inserted.

15. The motor according to any one of claims 1 to 14,

the insert part is manufactured by die casting.

16. The motor according to any one of claims 1 to 15,

the insert member is composed of an aluminum alloy.

Technical Field

The present invention relates to a motor.

Background

In recent years, motors in which a stator is molded with resin have been developed to simplify the assembly process and the like. Patent document 1 discloses a motor having a resin case for molding a stator.

Patent document 1: japanese laid-open patent application No. 2010-22191

The housing of patent document 1 has a hole portion for fastening a bolt for attachment to an external device. In such a motor, in order to obtain a sufficient fastening force by a bolt, it is conceivable to adopt a structure in which a nut is embedded in the interior of the housing. In this case, the nut is held by the housing which is a resin material. Therefore, the vibration generated from the rotor as the rotating portion is hard to escape from the fastening portion to the device, and there is a problem that the motor itself is likely to resonate.

Disclosure of Invention

In view of the above, an object of the present invention is to provide a motor capable of reducing vibration during driving.

One embodiment of a motor of the present invention includes: a rotor that rotates about a central axis; a stator radially opposed to the rotor; a housing made of resin and having the stator embedded therein; and an insert component. The insert member has: a main body portion embedded in the housing; and a fastened portion to which the fastening member is fastened. The main body portion and the fastened portion are constituted by one member.

According to one embodiment of the present invention, a motor capable of reducing vibration during driving is provided.

Drawings

Fig. 1 is a sectional view of a motor according to an embodiment.

FIG. 2 is a perspective view of an embodiment insert member.

FIG. 3 is a top view of an embodiment insert component.

Description of the reference symbols

1: a motor; 2: an insert member; 9 e: fixing bolts (fastening members); 10: a rotor; 20: a stator; 30: a housing; 36: an entry section; 40: a bearing holder portion (main body portion); 50: a nut portion (fastened portion); 50 a: an upper end surface (exposed end portion); 51: threaded holes (fastened holes); 61: an arm (1 st connecting part); 62: an annular bridge portion (2 nd connecting portion); 63: a radial bridge portion (3 rd joint portion); 64: an outer ring portion (4 th connecting portion); 64M: a neutral position; 69: a through hole; j: a central axis.

Detailed Description

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

In the following description, a direction parallel to the central axis J (see fig. 1) is simply referred to as an "axial direction" or a "vertical direction", a radial direction about the central axis J is simply referred to as a "radial direction", and a circumferential direction about the central axis J, that is, a direction around the central axis J is simply referred to as a "circumferential direction". In the present specification, one side in the axial direction along the center axis J is simply referred to as "upper side", and the other side is simply referred to as "lower side". The vertical direction in this specification is only for illustrative purposes, and is not limited to the posture of the motor during use and circulation.

Fig. 1 is a sectional view of a motor 1 according to an embodiment. As shown by the phantom line (two-dot chain line) in fig. 1, the motor 1 is attached to an external device 9 disposed on the upper side of the motor 1 using a fixing bolt (fastening member) 9 e. The motor 1 transmits power to the external device 9.

The motor 1 includes a rotor 10, a stator 20 surrounding the rotor 10, an upper bearing 15 and a lower bearing 16 rotatably holding the rotor 10, an insert member 2 holding the upper bearing 15, a lower bearing holder 70 holding the lower bearing 16, and a housing 30. The insert member 2 is embedded in the housing 30.

The rotor 10 rotates about a central axis J extending in the vertical direction. The rotor 10 has a shaft 11 extending along the center axis J, a rotor core 12, and a rotor magnet 13.

The shaft 11 is connected at an upper end (an end on one axial side) to a power transmission mechanism 9d of the external device 9. The shaft 11 is supported by an upper bearing 15 so as to be rotatable about the center axis J. A rotor core 12 is fixed to an outer peripheral surface of the shaft 11. Further, a rotor magnet 13 is fixed to the outer peripheral surface of the rotor core 12. The plurality of rotor magnets 13 may be embedded in the rotor core 12.

The stator 20 surrounds the rotor 10 from the radially outer side. The stator 20 is radially opposed to the rotor 10. The stator 20 has a stator core 21, an insulator 22, and a coil 29.

The stator core 21 includes an annular core back 21a centered on the central axis J and a plurality of teeth 21b extending radially inward from the core back 21 a. The plurality of teeth 21b are provided at equal intervals in the circumferential direction around the center axis J.

The coil 29 is attached to the tooth portion 21b via the insulator 22. The end of the coil 29 is supplied with electric power from the control device via a bus bar (not shown) disposed below the stator 20.

The upper bearing 15 is located at an upper side of the stator 20, and the lower bearing 16 is located at a lower side of the stator 20. The upper bearing 15 supports the upper end of the shaft 11, and the lower bearing 16 supports the lower end of the shaft 11. The upper bearing 15 and the lower bearing 16 of the present embodiment are ball bearings. However, the upper bearing 15 and the lower bearing 16 may be other types of bearings such as needle bearings.

The lower bearing holder 70 holds the lower bearing 16. The lower bearing holder 70 is located at the lower side of the stator 20. The lower bearing holder 70 is made of resin. The lower bearing holder 70 has a disk shape as viewed in the axial direction. The lower bearing holder 70 is fixed to the housing 30 at an outer edge portion.

The housing 30 is made of a resin material. In the present specification, the resin material may be a composite material reinforced with a fiber material such as glass fiber or carbon fiber. That is, the housing 30 may be made of a fiber-reinforced resin material.

The stator 20 and the insert member 2 are embedded in the housing 30. Thereby, the housing 30 holds the stator 20 and the insert member 2. The housing 30 is manufactured by insert molding in a state where the stator 20 and the insert member 2 are held in a mold. According to the present embodiment, since the stator 20 and the insert member 2 are embedded in the housing 30, the assembly process of the respective members can be simplified.

The housing 30 has an annular portion 32a protruding upward from the upper surface. The annular portion 32a is cylindrical with the center axis J as the center. The annular portion 32a is attached to the external device 9 and performs a part of the sealing function of the motor 1.

The external device 9 has a cylindrical retainer cylinder portion 9a centered on the central axis J. The retainer cylinder portion 9a surrounds the annular portion 32a from the radially outer side. A groove 9b extending in the circumferential direction is provided on the inner circumferential surface of the retainer tube portion 9 a. A seal member 9c is housed in the groove 9 b. The seal member 9c is compressed between the bottom surface of the recessed groove 9b and the outer peripheral surface of the annular portion 32 a. The seal member 9c suppresses entry of moisture into the inside of the retainer cylinder portion 9 a.

The insert part 2 is located at an upper side of the stator 20. The insert part 2 is composed of an aluminum alloy. Further, the insert component 2 is manufactured by die casting.

Fig. 2 is a perspective view of the insert part 2. Fig. 3 is a plan view of the insert part 2.

As shown in fig. 2, the insert member 2 includes a bearing holder portion (main body portion) 40, a plurality of nut portions (fastened portions) 50, a plurality of arm portions (1 st coupling portions) 61, an annular bridge portion (2 nd coupling portions) 62, a plurality of radial bridge portions (3 rd coupling portions) 63, and an outer ring portion (4 th coupling portion) 64. In the present embodiment, three nut portions 50, three arm portions 61, and three radial bridge portions 63 are provided in the insert member 2.

As shown in fig. 1, the bearing holder portion 40 is buried in the housing 30. The bearing holding portion 40 holds the upper bearing 15. The bearing holder portion 40 is located at the center of the insert member 2.

The bearing holder portion 40 includes a holder cylindrical portion (cylindrical portion) 41 and an upper plate portion 42 extending radially inward from an upper end of the holder cylindrical portion 41. The holder cylindrical portion 41 is cylindrical with the center axis J as the center. The upper bearing 15 is disposed radially inward of the holder cylindrical portion 41. The upper plate portion 42 covers the upper side of the outer ring of the upper bearing 15. The upper plate portion 42 is provided with a center hole 42a penetrating in the axial direction. The shaft 11 passes through the central hole 42 a.

The plurality of nut portions 50 are arranged in a row along the circumferential direction. The nut portion 50 is a columnar shape extending along a center line J2 parallel to the center axis J. The nut portion 50 is buried in the housing 30. The center line J2 of the nut portion 50 is parallel to the center axis J of the motor 1.

The upper end surface 50a of the nut portion 50 is exposed from the housing 30. The upper end surface 50a of the nut portion 50 functions as an exposed end portion exposed to the outside from the housing 30. The nut portion 50 has a threaded hole (fastened hole) 51 that is open at the upper end surface 50a and extends downward along the center line J2. The inner peripheral surface of the screw hole 51 is exposed from the housing 30. The shaft portion of the fixing bolt 9e is inserted into the screw hole 51.

The external device 9 has a plate-like fixing plate portion 9f extending radially outward from the lower end portion of the retainer cylinder portion 9 a. The external device 9 of the present embodiment has the same number (3 in the present embodiment) of fixing plate portions 9f as the nut portions 50. Each fixing plate portion 9f has a fixing hole 9g penetrating in the axial direction. In the fixing hole 9g, a fixing bolt 9e is inserted from the upper side. The motor 1 is fixed to the external device 9 by fastening the fixing bolt 9e to the screw hole 51 of the nut portion 50.

According to the present embodiment, since the nut portion 50 is made of a metal material, it is possible to suppress the occurrence of damage at the fastened portion due to stress at the time of fastening, as compared with a case where the external device 9 is directly fixed to the resin case 30. Therefore, the fastening strength of the motor 1 and the housing 30 can be improved. Further, by increasing the fastening strength of one fixing bolt 9e, the number of fixing bolts 9e for obtaining a desired fixing strength can be reduced, and the process of fixing the motor 1 to the external device 9 can be simplified.

The plurality of arm portions 61 radially extend outward in the radial direction from the bearing holder portion 40. The plurality of arm portions 61 are arranged at equal intervals in the circumferential direction. The arm portion 61 connects the bearing holder portion 40 and the nut portion 50.

According to the present embodiment, the bearing holder portion 40 and the nut portion 50 are constituted by one member connected via the arm portion 61. Therefore, the rigidity of the nut portion 50 can be increased, and the motor 1 can be firmly fixed to the external device 9. In addition, the natural frequency of the motor 1 with respect to the vibration frequency of the vibration generated by the motor 1 during driving can be sufficiently increased. As a result, resonance of the motor 1 can be suppressed, and vibration of the motor 1 during driving can be effectively reduced.

According to the present embodiment, the insert member 2 has both a function as a bearing holder and a function as a plurality of nuts. By providing a plurality of functions to one component, the number of components of the motor 1 can be reduced, and the manufacturing process can be simplified.

According to the present embodiment, the nut portion 50 overlaps the stator 20 when viewed in the axial direction. Therefore, the nut portion 50 can be prevented from protruding radially outward from the outer shape of the motor 1 when viewed in the axial direction. As a result, the motor 1 can be downsized in the radial direction.

In general, when a columnar member such as the nut portion 50 is embedded in a resin member, it is conceivable that the upper end surface and the lower end surface are held in a mold by being sandwiched between the mold and the resin member. According to the present embodiment, since the nut portion 50 is a part of the insert member 2, it is not necessary to sandwich the nut portion 50 with a mold. Therefore, the lower end surface of the nut portion 50 can be disposed to face the stator 20 inside the housing 30. As a result, the nut portion 50 can be arranged to overlap the stator 20 as viewed in the axial direction.

A rib 61a is provided at the lower end of the arm portion 61. The rib 61a is plate-shaped along a plane perpendicular to the central axis J. The ribs 61a extend from the lower end of the arm 61 to both sides in the circumferential direction. As shown in fig. 3, the circumferential dimension of the rib 61a becomes larger toward the radially outer side. The radially outer end of the rib 61a is connected to the lower end of the outer ring portion 64. The ribs 61a reinforce the arm portions 61 to suppress vibration. This reduces relative vibration between the bearing holder portion 40 and the nut portion 50.

The annular bridge 62 is annular with the center axis J as the center. The annular bridge 62 is cross-connected to the plurality of arms 61. The annular bridge portion 62 is reinforced by the plurality of arm portions 61 being connected to each other. This can suppress vibration of the arm portion 61, and reduce relative vibration between the bearing holder portion 40 and the nut portion 50.

As shown in fig. 2, the height dimension (axial dimension) of the arm portion 61 is larger than the height dimension of the annular bridge portion 62. By increasing the height of the arm portion 61, relative vibration between the bearing holder portion 40 and the nut portion 50 can be effectively suppressed. On the other hand, annular bridge 62 contributes less to vibration reduction than arm 61, and therefore it is preferable to reduce the height and weight as a whole.

The radial bridge portion 63 extends radially outward from the bearing holder portion 40. The radial bridge portion 63 is located between the arm portions 61 adjacent in the circumferential direction. Radial bridge 63 is connected to annular bridge 62 and outer ring 64. The radial bridge portion 63 connects the respective portions of the insert member 2, thereby increasing the rigidity of the entire insert member 2 and increasing the rigidity of the insert member 2. As shown in fig. 2, the height dimension of arm portion 61 is larger than the height dimension of radial bridge portion 63. This can reduce the weight of the entire insert member 2 and effectively reduce vibration.

The outer ring portion 64 is annular with the center axis J as the center. The outer ring portion 64 connects the plurality of nut portions 50 to each other. The outer ring portion 64 is connected to the arm portion 61 and the radial bridge portion 63.

According to the present embodiment, the plurality of nut portions 50 are coupled to each other at the outer ring portion 64. Therefore, the rigidity of the nut portion 50 can be improved as compared with a case where a plurality of insert nuts are embedded in the housing 30, respectively. This can increase the natural frequency of the motor 1 and effectively reduce the vibration of the motor 1 during driving.

Further, according to the present embodiment, the accuracy of the relative position between the screw holes 51 can be easily improved as compared with a case where a plurality of insert nuts are embedded in the housing 30. Further, according to the present embodiment, the nut portion 50 and the bearing holder portion 40 are also formed of one member. Therefore, the accuracy of the relative position between the bearing holder portion 40 and each of the screw holes 51 can be easily improved.

The height dimension (axial dimension) and the thickness dimension (radial dimension) of the outer ring portion 64 are not uniform. As shown in fig. 2, the height dimension and the thickness dimension of the outer ring portion 64 are largest at a portion passing through the nut portion 50. In addition, the height dimension and the thickness dimension of the outer ring portion 64 become smaller as being distant from the nut portion 50 between the pair of nut portions 50, and are smallest at the intermediate position 64M.

According to the present embodiment, the rigidity of the nut portion 50 can be effectively increased by maximizing the height and thickness of the outer ring portion 64 around the nut portion 50. Further, by minimizing the height dimension and the thickness dimension of the outer ring portion 64 in the region away from the nut portion 50, it is possible to achieve a reduction in weight of the region that contributes little to the rigidity of the nut portion 50. As a result, the entire insert member 2 can be reduced in weight, and sufficient rigidity can be ensured.

In addition, in the case where only the rigidity of the nut portion 50 is considered, a shape in which the outer ring portion 64 is interrupted at the intermediate position 64M is also conceivable. However, in the present embodiment, since the insert component 2 is manufactured by die casting, the flow efficiency of the molten material in the mold can be improved by forming the outer ring portion 64 into a ring shape. As a result, the outer ring portion 64 and the insert member 2 can be manufactured with high accuracy. The method of manufacturing the insert component 2 is not limited to the die casting method. For example, the insert component 2 may be manufactured by a casting method other than the die casting method.

As shown in fig. 3, the insert member 2 has a plurality of through holes 69 that penetrate in the axial direction between the bearing holder portion 40 and the outer ring portion 64. The plurality of through holes 69 are defined by the annular bridge 62 and the radial bridge 63.

As shown in fig. 1, by embedding the insert member 2 in the housing 30, the entering portion 36 of the housing 30 enters the through hole 69. That is, the housing 30 has the entering portion 36 that enters the through hole 69. When a force in the circumferential direction is applied to the insert member 2, the entering portion 36 interferes with the radial bridge portion 63 to suppress the rotation of the insert member 2.

For example, in the above-described embodiment, a case where the main body portion of the insert member 2 functions as the bearing holder portion 40 has been described. However, the structure of the body portion is not limited as long as it is a part of the insert member 2 embedded in the housing 30.

While one embodiment of the present invention has been described above, the configurations and combinations thereof in the embodiment are merely examples, and additions, omissions, substitutions, and other modifications of the configurations can be made without departing from the spirit of the present invention. The present invention is not limited to the embodiments.

The application of the motor unit of the above embodiment is not particularly limited. The motor unit according to the above-described embodiment and the modifications thereof is mounted on, for example, an electric pump, an electric power steering apparatus, and the like.