CN110971047A

CN110971047A - Motor with a stator having a stator core

Info

Publication number: CN110971047A
Application number: CN201910922414.2A
Authority: CN
Inventors: 中村紘通
Original assignee: Nidec Corp
Current assignee: Nidec Corp
Priority date: 2018-09-28
Filing date: 2019-09-27
Publication date: 2020-04-07
Anticipated expiration: 2039-09-27
Also published as: JP2020054207A; JP7081429B2; CN110971047B

Abstract

Provided is a new motor structure capable of bending a lead wire of a coil into a stable shape without performing an additional process using a jig or the like. The coil holder (30) supports a plurality of lead wires (21a) which are respectively led out from the plurality of coils (21) to the upper side of the stator (20) in the axial direction. The coil support (30) has: an annular portion (31) located axially above the stator (20); a plurality of holding wall portions (32) that protrude upward in the axial direction from the annular portion (31); and a rib (34) that protrudes axially downward from the annular portion (31). The holding wall (32) has an opening (32a) into which the lead wire (21a) can be inserted. The rib (34) is located between the position where the lead wire (21a) is drawn out and the holding wall (32) in the radial direction.

Description

Motor with a stator having a stator core

Technical Field

The present invention relates to a motor.

Background

In order to obtain the power supply, the coil windings of the motor need to be electrically connected to a motor control device called ECU. Therefore, a support member for guiding the coil winding to a desired lead-out direction is sometimes used.

For example, patent document 1 discloses that a lead wire drawn out from a coil is positioned with respect to a bus bar terminal end through a coil through hole of a bus bar mold (paragraph 0024).

Patent document 1: japanese patent laid-open publication No. 2013-219933

However, in the motor of patent document 1, it is necessary to bend the lead wire on the winding end side of the coil so as to avoid the lead wire from becoming unstable (paragraph 0040). This requires additional processing of the lead wire by a jig or the like, which leads to an increase in the time required for the working process.

Disclosure of Invention

The present invention has a main object to provide a new motor structure capable of bending a lead wire of a coil into a stable shape without performing an additional process using a jig or the like.

In order to achieve the above object, a motor according to a first exemplary embodiment of the present invention includes: a rotor having a shaft centered on a central axis extending in an axial direction; a stator having a plurality of coils, the stator being disposed radially opposite the rotor; and a coil holder that supports a plurality of lead wires that are respectively led out from the plurality of coils to an upper side in an axial direction of the stator, the coil holder including: an annular portion located axially above the stator and having an annular shape; a plurality of holding wall portions that are arranged along the inner periphery or the outer periphery of the annular portion and protrude upward in the axial direction; and at least one rib protruding from the annular portion toward an axially lower side, the plurality of holding wall portions having openings into which the plurality of lead wires are inserted, the plurality of lead wires extending from a lead-out position of the lead wires toward the plurality of holding wall portions in a radial direction, the rib being located between the lead-out position and the plurality of holding wall portions in the radial direction.

According to the exemplary first invention of the present application, the lead wire of the coil can be bent into a stable shape without performing an additional process using a jig or the like.

Drawings

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

Fig. 2 is a perspective view of a motor according to an embodiment in an exploded state of a stator and a coil holder.

Fig. 3 is a perspective view of a state in which a stator and a coil holder constituting a motor according to an embodiment are assembled.

Fig. 4 is a bottom view of a coil holder constituting a motor of an embodiment.

Fig. 5 is a perspective view of the lower surface of a coil holder constituting a motor according to an embodiment.

Fig. 6 is a diagram showing a state in which a coil holder holds coil lead-out wires in a motor of one embodiment.

Fig. 7 is a diagram showing a bent shape of a lead wire of a coil constituting a motor according to an embodiment.

Fig. 8 is a plan view of a coil holder constituting a motor according to a modification.

Description of the reference symbols

1: a motor; 10: a rotor; 11: a shaft; 12: a first bearing; 13: a second bearing; 14: a rotor core; 15: a rotor magnet; 20: a stator; 21: a coil; 21 a: an outgoing line; 21 b: a lead-out position; 25: a stator core; 25 a: the back of the iron core; 25 b: a tooth portion; 26: an upper insulator; 27: a lower insulator; 30. 30A: a coil support; 31: an annular portion; 32: a holding wall portion; 32 a: an opening part; 33: a guide section; 34: a rib; 35: a leg portion; 40: a bearing retainer; 50: a bus bar unit; 60: a housing.

Detailed Description

Hereinafter, a motor according to an embodiment of the present invention will be described with reference to the drawings. The scope of the present invention is not limited to the following embodiments, and may be arbitrarily changed within the scope of the technical idea of the present invention. In the following drawings, the scale, number, and the like of each structure may be different from the actual structure in order to facilitate understanding of each structure.

In the following description, the Z axis is set to be parallel to the central axis J of the motor, and the positive side (+ Z side) in the Z axis direction is referred to as "upper side", and the negative side (-Z side) in the Z axis direction is referred to as "lower side". In the following description, unless otherwise specified, a radial direction around a central axis J extending in the vertical direction (Z-axis direction) will be simply referred to as a "radial direction", a circumferential direction around the central axis J, that is, a direction around the central axis J will be simply referred to as a "circumferential direction", and a direction parallel to the central axis J (that is, the vertical direction or the Z-axis direction) will be referred to as an axial direction.

In addition, in the present specification, "extend in the axial direction" includes a case of extending in a direction inclined in a range of less than 45 ° with respect to the axial direction, in addition to a case of extending strictly in a direction parallel to the central axis J. Further, "extending in the radial direction" includes, in addition to the case of extending strictly in the radial direction, i.e., in the direction perpendicular to the up-down direction (Z-axis direction), the case of extending in a direction inclined in a range of less than 45 ° with respect to the radial direction.

Fig. 1 is a sectional view of a motor 1 of the present embodiment. As shown in fig. 1, a motor 1 of the present embodiment includes a rotor 10, a stator 20, a coil holder 30, a bearing holder 40, a bus bar unit 50, and a housing 60.

The rotor 10 includes a shaft 11, a rotor core 14, and a rotor magnet 15. The shaft 11 is rotatable about a central axis J extending in the Z-axis direction. The rotor core 14 circumferentially surrounds the shaft 11 and is fixed to the shaft 11. The rotor magnet 15 is fixed to the outer surface of the rotor core 14 in the circumferential direction. The rotor core 14 and the rotor magnet 15 rotate integrally with the shaft 11. The shaft 11 is supported by a first bearing 12 and a second bearing 13 so as to be rotatable about a center axis J. The first bearing 12 is located at an upper side of the stator 20, and the second bearing 13 is located at a lower side of the stator 20. The structure of the first bearing 12 and the second bearing 13 is not particularly limited, and any known bearing may be used.

The stator 20 is disposed to face the rotor 10 in the radial direction. The stator 20 is fixed to the housing 60. The stator 20 includes a plurality of coils 21, a stator core 25, an upper insulator 26, and a lower insulator 27. The number of coils 21 is, for example, 12. The lead wires 21a are led out from the respective coils 21 to the upper side of the stator 20. The stator core 25 has an annular structure surrounding the rotor 10. The stator core 25 includes an annular core back 25a centered on the central axis J and a plurality of teeth 25b extending radially inward from the core back 25 a. The core back 25a annularly connects radially outer sides of the plurality of teeth 25 b. The plurality of teeth 25b are arranged at equal intervals in the circumferential direction over a circumferential range. The number of the teeth 25b is, for example, 12. The coil 21 is wound around each tooth portion 25b via an upper insulator 26 and a lower insulator 27. The upper insulator 26 is located on the upper side of the stator core 25. The lower insulator 27 is located at the lower side of the stator core 25. The upper insulator 26 and the lower insulator 27 cover circumferential end surfaces and axial end surfaces of the teeth 25b of the stator core 25.

The coil holder 30 is disposed above the stator 20 and supports the plurality of lead wires 21 a. The bearing holder 40 is disposed above the coil support 30 and supports the first bearing 12. The bearing holder 40 is fixed to the housing 60. The bus bar unit 50 is disposed above the bearing holder 40 and covers an opening on the upper side of the housing 60. The bus bar unit 50 is fixed to the housing 60. The housing 60 houses the components of the motor 1 (the rotor 10, the stator 20, the coil holder 30, the bearing holder 40, the bus bar unit 50, and the like).

Fig. 2 and 3 are perspective views of the stator 20 and the coil holder 30 according to the present embodiment in an exploded state and in an assembled state, respectively. In fig. 2 and 3, the same components as those in fig. 1 are denoted by the same reference numerals.

As shown in fig. 2 and 3, one lead wire 21a is drawn from one coil 21. Since the stator 20 of the present embodiment has 12

coils

21, 12 lead wires 21a are drawn upward in the axial direction from the stator 20. The 12 lead wires 21a are end portions of coil wires constituting the coil 21.

As shown in fig. 2 and 3, the coil holder 30 includes an annular portion 31 located axially above the stator 20, and a plurality of holding wall portions 32 projecting axially upward. The annular portion 31 has an annular shape having a width (a space between an inner periphery and an outer periphery) in a radial direction. The plurality of holding wall portions 32 are arranged at equal intervals along the inner periphery of the annular portion 31. In the present embodiment, since 12 lead wires 21a are led out from the stator 20, the coil holder 30 has 12 holding wall portions 32. Since the holding wall portions 32 are arranged along the inner periphery of the annular portion 31, the holding wall portions 32 hold the lead wires 21a radially inward of the annular portion 31.

Each holding wall portion 32 has an opening 32a into which the lead wire 21a of the coil 21 can be inserted in the axial direction. Each opening 32a penetrates the annular portion 31 in the axial direction. Each holding wall portion 32 extends axially upward along the inner peripheral surface of the portion of each opening portion 32a that penetrates the annular portion 31. That is, the inner circumferential surface of each holding wall 32 is continuous with the inner circumferential surface of the portion of each opening 32a that penetrates the annular portion 31. Each of the holding wall portions 32 is formed in a U shape that opens in the circumferential direction when viewed from above. Each holding wall portion 32 includes a pair of wall portions facing each other on the radially inner side and the radially outer side with each opening portion 32a interposed therebetween, and the lead wire 21a is arranged so as to be sandwiched between the pair of wall portions. This enables the lead wire 21a to be stably held as compared with the case where the holding wall portion 32 is not provided.

The lead wire 21a is routed from the coil 21 to the holding wall 32 (opening 32a) in the radial direction from the lead position 21b on the radially outer side of the stator 20 (the core back 25a side of the stator core 25) to the upper side of the stator 20. That is, the lead wire 21a extending from the coil 21 is routed from the radially outer side to the radially inner side on the upper side of the stator 20, and is held by the holding wall portion 32 (opening portion 32a) of the coil holder 30 at a position closer to the radially inner side of the stator 20. Each lead wire 21a passes through the opening 32a of the holding wall 32 and is electrically connected to the bus bar unit 50 (see fig. 1) above the coil holder 30.

The coil holder 30 is made of an insulating material such as resin, for example. In the coil holder 30, the upper and lower surfaces of the annular portion 31 are perpendicular to the central axis J (Z axis). A circular opening concentric with the shaft 11 (see fig. 1) is provided in the center of the annular portion 31, and the shaft 11 penetrates through the circular opening. The annular portion 31 is located above the stator 20 and below the bearing holder 40. Thus, the annular portion 31 covers the upper side of the lead wire 21a wound on the upper side of the stator 20, thereby ensuring insulation between the lead wire 21a and the bearing holder 40.

Fig. 4 and 5 are a bottom view and a bottom side perspective view of the coil holder 30 of the present embodiment, respectively, and fig. 6 is a view showing a state in which the coil holder 30 holds the lead wire 21a of the coil 21 in the present embodiment. In fig. 6, the same components as those in fig. 1 are denoted by the same reference numerals.

As shown in fig. 4 to 6, the opening 32a of each holding wall 32 opens in the circumferential direction. Here, the openings 32a of the respective holding wall portions 32 are all open toward the same side in the circumferential direction. The annular portion 31 has a plurality of guide portions 33 for guiding the lead wires 21a to the opening 32 a. Each guide portion 33 is a slit that penetrates the annular portion 31 in the axial direction. Each guide portion 33 extends from the opening of each opening 32a along the inner periphery of the annular portion 31, and opens radially inward. Therefore, when the coil holder 30 is attached to the stator 20, the lead wires 21a are aligned with the openings 32a via the guide portions 33 only by disposing the lead wires 21a in the vicinity of the guide portions 33 and rotating the coil holder 30 in the circumferential direction (toward the guide portions 33). That is, the insertion process of the lead wires 21a into the coil holder 30 can be simplified.

As shown in fig. 4 to 6, the coil holder 30 has a rib 34 projecting axially downward from the lower surface of the annular portion 31. In the state where the coil holder 30 is attached to the stator 20, the rib 34 is positioned between the lead-out position 21b of each lead wire 21a (the core back 25a side in the present embodiment: see fig. 2) and each holding wall portion 32. The coil holder 30 has a plurality of (for example, three) leg portions 35 arranged along the outer periphery of the annular portion 31 and extending axially downward. The leg portions 35 are arranged at equal intervals in the circumferential direction. The leg portions 35 are held on the upper surface of the stator core 25, whereby the coil support 30 is fixed to the stator 20.

According to the present embodiment, the coil holder 30 has the rib 34 that is positioned between the lead-out position 21b of the lead wire 21a and the holding wall portion 32 and protrudes downward in the axial direction. Therefore, when the coil holder 30 is attached to the stator 20, the lead wire 21a extending in the radial direction can be folded from the rib 34 as a starting point to be provided with a fold. The bent lead wire 21a is inserted into the opening 32a of the holding wall 32 so as to be led upward in the axial direction of the stator 20. As a result, the lead wires 21a are fixed to the holding wall portion 32 without applying a load to the coil holder 30, and therefore the coil holder 30 is stably fixed to the stator 20. Further, since the lead wire 21a can be bent into a stable shape without performing an additional process such as a shaping operation using a jig or the like, the mounting strength of the coil holder 30, that is, the reliability of the motor 1 can be improved while suppressing an increase in the operation process time.

Fig. 7 shows a case where the lead wire 21a held by the holding wall portion 32 is shaped by the rib 34 in the present embodiment. In addition, if the lead-out wires 21a are fixed without applying a load to the coil support 30 by shaping using the ribs 34, the ribs 34 and the lead-out wires 21a do not necessarily have to be in contact in the final product.

On the other hand, in the case where the rib 34 is not formed in the coil holder 30 of the present embodiment, if an additional step such as a shaping operation using a jig or the like is not performed, the lead wire 21a cannot be sufficiently bent to be provided with a fold. Therefore, when the lead wires 21a are held by the holding wall portion 32, a load is applied from the lead wires 21a to the holding wall portion 32, that is, the coil holder 30. As a result, the coil holder 30 cannot be stably fixed to the stator 20. Specifically, deformation due to insufficient mounting strength of the coil holder 30 occurs depending on the shaping state of the lead wires 21a, which may cause a problem in the process. On the other hand, when the lead wire 21a is subjected to the shaping work using a jig or the like, the work time increases, and the manufacturing cost increases because a jig or the like having a complicated shape is prepared.

In the present embodiment, the lead wires 21a are led out from the core back 25a side of the stator core 25, and the holding wall portions 32 are arranged along the inner periphery of the annular portion 31 covering the upper side in the axial direction of the stator 20. Therefore, by providing the rib 34 between the lead-out position 21b of each lead wire 21a and each holding wall portion 32, it is possible to reliably provide a fold to each lead wire 21a extending from the radial outer side to the radial inner side so as to be bent in the axial direction at the radial inner side.

As shown in fig. 4 and 5, in the present embodiment, the rib 34 is provided in an annular shape at a position radially outward of each holding wall 32 along the inner circumference of the annular portion 31 where each holding wall 32 is disposed. Therefore, the ribs 34 can be reliably provided between the lead-out positions 21b of the lead wires 21a and the holding wall portions 32.

In the present embodiment, as shown in fig. 7, for example, the wall surface 34a of the rib 34 on the side of the holding wall 32 forms a larger angle with the radial direction than the wall surface 34b on the opposite side. Therefore, when the lead wires 21a extending in the radial direction from the lead positions 21b toward the holding wall portions 32 are inserted into the opening portions 32a and bent in the axial direction, the top portions 34c of the ribs 34 can reliably impart a fold to the lead wires 21 a.

Further, as shown in fig. 7, for example, in the present embodiment, the rib 34 is located in the vicinity of each holding wall portion 32 in the radial direction with respect to the lead-out position 21b of each lead wire 21 a. Therefore, when the lead wires 21a extending in the radial direction from the lead positions 21b toward the holding wall portions 32 are inserted into the opening portions 32a and bent in the axial direction, the lead wires 21a easily contact the ribs 34, and therefore, the fold lines are easily provided to the lead wires 21 a.

In the present embodiment, each holding wall 32 may be provided between the teeth 25b of the stator core 25. In this way, when the lead-out positions 21b of the lead wires 21a are provided between the teeth portions 25b of the stator core 25, the lead wires 21a can be held by the holding wall portions 32 without applying a load in the circumferential direction to the lead wires 21 a.

The embodiments of the present invention have been described above, but the present invention is not limited to the embodiments and various modifications can be made within the scope of the present invention. That is, the description of the above embodiments is merely exemplary in nature and is not intended to limit the present invention, its applications, or its uses.

For example, in the present embodiment, the lead-out positions 21b of the lead wires 21a are provided on the core back 25a side of the stator core 25, and the holding wall portions 32 are provided on the inner peripheral side of the annular portion 31 (on the tooth portion 25b side of the stator core 25). Instead, the lead-out positions of the lead wires 21a may be provided on the tooth portion 25b side of the stator core 25, and the holding wall portions 32 may be provided on the outer peripheral side of the annular portion 31 (on the core back portion 25a side of the stator core 25). In this case, the rib 34 is provided between the lead position of each lead wire 21a and each holding wall portion 32, whereby the same effect as the present embodiment can be obtained.

In the present embodiment, one annular rib 34 is formed along the inner periphery of the annular portion 31 where each holding wall portion 32 is disposed (see fig. 4 and 5). However, the ribs 34 are not limited to this, and may be present between the lead-out positions of the lead wires 21a and the holding wall portions 32. For example, a plurality of independent ribs may be provided for each lead wire 21a or for each group of, for example, 2 to 6 lead wires 21 a.

In the present embodiment, the angle formed by the wall surface 34a of the rib 34 on the side of the holding wall 32 and the radial direction is made larger than the angle formed by the wall surface 34b on the opposite side and the radial direction (see fig. 7). Specifically, the cross-sectional shape of the rib 34 in the radial direction is a substantially right triangle in which the wall surface 34a on the side of the holding wall portion 32 is substantially perpendicular to the radial direction. However, the rib 34 is not limited to this, and may have any shape as long as it can give a fold to the lead wire 21 a. For example, the radial cross-sectional shape of the rib 34 may be a triangular shape, a quadrangular shape, or the like having corners.

In the present embodiment, the rib 34 is located in the vicinity of each holding wall 32 in the radial direction from the lead-out position 21b of each lead wire 21a (see fig. 7). However, the position of the rib 34 is not particularly limited as long as the rib 34 is present between the position where the lead wire 21a is drawn and the holding wall portion 32.

In the present embodiment, the opening 32a of each holding wall 32 is opened in the circumferential direction. However, the shape of each holding wall portion 32 including the opening portion 32a is not particularly limited. For example, as in the coil holder 30A of the modification shown in fig. 8, the opening 32a of each holding wall 32 may be opened radially inward.

Claims

1. A motor, comprising:

a rotor having a shaft centered on a central axis extending in an axial direction;

a stator having a plurality of coils, the stator being disposed to face the rotor in a radial direction; and

a coil holder that supports a plurality of lead wires that are respectively led out from the plurality of coils to an upper side in an axial direction of the stator,

the coil support has:

an annular portion located axially above the stator and having an annular shape;

a plurality of holding wall portions that are arranged along an inner periphery or an outer periphery of the annular portion and protrude upward in the axial direction; and

at least one rib projecting axially downward from the annular portion,

the plurality of holding wall portions have openings into which the plurality of lead wires are inserted,

the plurality of lead wires extend from the lead-out positions of the lead wires in the radial direction toward the plurality of holding wall portions,

the rib is located between the lead-out position and the plurality of holding wall portions in a radial direction.

2. The motor of claim 1,

the stator is located radially outward of the rotor,

the stator has a stator core having a stator core,

the stator core has:

a plurality of teeth portions around which respective coils of the plurality of coils are wound; and

a core back portion connecting radially outer sides of the plurality of tooth portions in a ring shape,

the plurality of lead-out wires are respectively led out from the core back side of the stator core,

the plurality of holding wall portions are arranged along the inner periphery of the annular portion.

3. The motor according to claim 1 or 2,

the opening portion is open toward the circumferential direction,

the annular portion has a guide portion that is a slit that is continuous with the opening portion in the circumferential direction and that opens in the radial direction.

4. The motor according to any one of claims 1 to 3,

the angle formed by the wall surface of the rib on the side of the plurality of holding wall portions with the radial direction is larger than the angle formed by the wall surface on the opposite side of the wall surface with the radial direction.

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

the rib is located in the vicinity of the plurality of holding wall portions in a radial direction from the lead-out position.

6. The motor according to any one of claims 1 to 5,

the rib is provided annularly in the circumferential direction.