JP2020025406A - Motor manufacturing method, motor, and electrically-driven power steering device - Google Patents

Abstract

To provide a motor manufacturing method capable of easily adjusting a mounting position to the other member, and a motor.SOLUTION: In a manufacturing method of a motor 1, one motor mounting member 10 is selected from among multiple motor mounting members with different radial dimensions. A housing 20 includes a first end face 23a. A main body part 12 of the motor mounting member 10 includes a second end face 12a opposed to the first end face 23a. At two or more joint positions 25 provided in the first end face 23a and the second end face 12a, one end of the housing 20 in an axial direction and the main body part 12 of the selected motor mounting member 10 are joined in the axial direction. The manufacturing method also includes fixing a stator 40 within the housing 20, and mounting a rotor 30 within the housing 20.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a motor manufacturing method, a motor, and an electric power steering device.

  As a structure for mounting a motor to another member, a motor mounting member having a flange portion is known. The motor mounting member is fixed to one axial end of the motor. As a method for fixing the motor mounting member to the motor, a method is known in which a concave portion is formed on the outer peripheral portion at one end in the axial direction of the motor, and the concave portion and a protrusion formed on the outer peripheral portion of the motor mounting member are caulked and fixed. (For example, see Patent Document 1). Further, a method of caulking and fixing an outer peripheral portion at one axial end of a housing and a tapered portion of an outer peripheral portion of a motor mounting member is known (see Patent Document 2).

JP-A-2015-6089 Japanese Utility Model Publication No. 64-006757

  In the motors of Patent Literature 1 and Patent Literature 2, the size of the motor mounting member corresponds to the inner diameter of the housing. Therefore, the mounting position of the motor on another member is determined by the inner diameter of the housing. Therefore, it is difficult to adjust the mounting position of the motor, which is inconvenient.

  An object of the present invention is to provide a method of manufacturing a motor and a motor that can easily adjust a mounting position on another member.

  A method for manufacturing a motor according to an exemplary embodiment of the present application includes a shaft extending along a central axis and having bearings at both ends in an axial direction, a rotor fixed to the shaft, and a stator arranged radially outside the rotor. A motor having a housing disposed radially outside the stator and a motor mounting member is manufactured. The motor mounting member is a motor mounting member for mounting a motor to another member, and has a main body facing one axial end of the housing, and a flange protruding radially outward from the main body. A method for manufacturing a motor includes selecting one motor mounting member from a plurality of motor mounting members having different radial dimensions, and having one axial end of a housing having a first end surface and a second end surface facing the first end surface. The method includes a step of axially joining the main body of the one motor mounting member at two or more joining positions provided on the first end face and the second end face. The method also includes securing the stator within the housing and mounting the rotor within the housing.

  According to the method for manufacturing a motor according to an exemplary embodiment of the present application, one motor mounting member is selected from a plurality of motor mounting members having different radial dimensions, and one axial end of a housing having a first end surface is selected. The motor mounting member is fixed to the housing by joining the main body portion of the motor attaching member having the second end face facing the first end face at two or more joining positions provided on the first end face and the second end face. I do. For this reason, it is possible to select an optimal motor mounting member from motor mounting members having different radial dimensions without depending on the housing, and mount the motor to another member. Therefore, it is possible to realize a motor manufacturing method and a motor that can easily adjust a mounting position on another member.

FIG. 1 is a cross-sectional view illustrating the motor according to the first embodiment. FIG. 2 is a perspective view of the housing of the first embodiment as viewed from the bottom. FIG. 3 is a bottom view of the housing to which the motor mounting member according to the first embodiment is mounted. FIG. 4 is a cross-sectional view of the joint according to the first embodiment. FIG. 5 is a diagram illustrating the joining process of the first embodiment. FIG. 6 is a sectional view of a housing to which a motor mounting member according to the second embodiment is joined. FIG. 7 is a bottom view of the housing to which the motor mounting member according to the second embodiment is mounted. FIG. 8 is a cross-sectional view of a joint according to the second embodiment. FIG. 9 is a schematic diagram of an electric power steering device according to another embodiment.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the scope of the present invention is not limited to the following embodiments, and can be arbitrarily changed within the technical idea of the present invention.

  In the following description, C is the central axis of the motor. The direction in which the central axis C extends is defined as the axial direction. Further, one along the axial direction is defined as an upper side, and the other is defined as a lower side. However, the vertical direction in this specification is used for specifying a positional relationship, and does not limit an actual direction or a positional relationship. The direction of gravity is not necessarily downward. In this specification, a direction perpendicular to the rotation axis of the motor is referred to as a “radial direction”. A direction along an arc centered on the rotation axis of the motor is called a “circumferential direction”.

  In the drawings used in the following description, characteristic portions may be enlarged for convenience in order to emphasize characteristic portions. Therefore, the dimensions and ratios of the components are not always the same as actual ones.

(1st Embodiment)
<Motor>
As shown in FIG. 1, the motor 1 includes a shaft 31, a rotor 30, a stator 40, a bus bar support 50, a housing 20, and a motor mounting member 10.

  The shaft 31 extends along the central axis C, and is supported by the upper bearing 71 and the lower bearing 72 so as to be rotatable around the central axis C. The rotor 30 is fixed to the shaft 31 and rotates together with the shaft 31 around the central axis C. The upper bearing 71 is held by the bearing holder 28 located above the stator 40.

  The stator 40 is disposed radially outside the rotor 30 so as to face the rotor 30. The stator 40 has a stator core 41, an insulator 42, and a coil wire 43. The insulator 42 is attached to a tooth (not shown) of the stator core 41. The coil wire 43 is an example of a conductive portion, is formed of a conductive wire, and is wound around the teeth with the insulator 42 interposed therebetween. A lead wire drawn out of the coil wire 43 wound around the stator 40 and above the stator 40 is connected to the bus bar 61.

  The bus bar 61 is held by a bus bar support 50 made of an insulating material such as a resin, and is arranged above the stator 40 in the axial direction. The bus bar 61 is electrically connected to the control board 80 via an electric wire (not shown). The control board 80 is disposed above the stator 40 and includes a drive circuit (not shown) configured from electronic components of the motor 1. The bus bar 61 may have an external connection terminal (not shown) connected to an external power supply.

  The housing 20 is disposed radially outward of the stator 40, and the stator 40 is shrink-fitted on the inner peripheral surface of the housing 20, fixed by crimping, press-fitting, bonding, or the like. The housing 20 is made of a metal material, has a cylindrical shape with a bottom centered on the central axis C, and has a bottom portion 23 at a lower end in the axial direction. Note that the shape of the housing 20 is not limited to a cylindrical shape. Further, the radial cross section of the housing 20 may be, for example, a polygon.

  As shown in FIG. 2, the housing 20 has a first end face 23a, a first center hole 27a, and a first annular wall 27b on the bottom 23. The first center hole 27a is formed at the radial center of the first end face 23a, and passes the shaft 31 shown in FIG. The first annular wall portion 27b surrounds the first center hole 27a and forms the lower bearing holder 27. As shown in FIG. 1, the first annular wall portion 27b extends inward of the housing 20 from an inner end surface 23b opposite to the first end surface 23a. The first annular wall portion 27b accommodates the lower bearing 72. By providing the lower bearing holder 27 inside the housing 20 in this way, the axial size of the motor 1 can be reduced. Note that the axial height of the first annular wall portion 27b may not be a height that accommodates the entire lower bearing 72, but may be a height that accommodates a portion of the lower bearing 72. Good.

  As shown in FIG. 1, the motor mounting member 10 is a member made of a metal material for mounting the motor to another member 90. The motor mounting member 10 is fixed to another member 90 by bolts (not shown) inserted into mounting holes 17 provided on both radial sides of the flange portion 11.

  The motor mounting member 10 has a main body 12 and a flange 11 as shown in FIG. As shown in FIG. 1, the main body 12 has a second end face 12 a axially opposed to the first end face 23 a of the housing 20. The flange portion 11 extends from the outer periphery of the main body portion 12 to the outside of the housing 20 in the radial direction.

The main body 12 of the motor mounting member further has a second center hole 18 and a second annular wall 19, as shown in FIG. The second center hole 18 faces the first center hole 27 a of the housing 20 in the axial direction, and passes the shaft 31. The second annular wall portion 19 surrounds the second center hole 18 and extends in the axial direction from the outer end surface 12b opposite to the second end surface 12a.
The bottom part 23 of the housing 20 and the main body part 12 of the motor mounting member 10 are joined in the axial direction via a joining part 15. As shown in FIGS. 2 and 3, the joints 15 are formed at four joint positions 25 provided on the inner diameter side of the outer periphery of the main body 12 of the motor mounting member 10. The joining positions 25 are provided at equal intervals in the circumferential direction around the central axis C.

Each joint 15 is formed by, for example, TOX (registered trademark) caulking described later. As shown in FIG. 4, each joint portion 15 includes a concave portion 15 a that is one side in the axial direction and that is recessed inside the housing 20. The joint 15 or the recess 15a may have a trapezoidal shape as shown in the illustrated example or a rectangular shape, depending on the shape of a jig described later.
As described above, in the motor 1 according to the above-described embodiment, the joint 15 that joins the housing 20 and the motor mounting member 10 can be formed without protruding outside the housing 20. In the conventional motor (for example, Patent Literature 1), the swaged portion protrudes radially outward of the housing and in the axial direction. . Such contact may damage other members. In another conventional motor (for example, Patent Document 2), since a step is provided at the outer peripheral edge of one end in the axial direction of the housing, the caulked portion does not protrude, but the overall length of the motor becomes longer. On the other hand, in the motor 1 according to the above-described embodiment, since the portion protruding outside the housing 20 is not formed, the other members 90 are not easily damaged when the motor 1 is mounted. Further, the influence of the motor mounting member 10 on the size of the motor 1 in the axial direction can be minimized.

<Motor manufacturing method>
In manufacturing the motor 1, first, a plurality of motor mounting members having different radial dimensions are prepared, and one of the motor mounting members is selected. The lower end in the axial direction of the housing 20 and the main body 12 of the selected motor mounting member 10 are axially joined at four predetermined joining positions 25. The joining is performed by, for example, the following TOX (registered trademark) caulking.

  As shown in FIG. 5, a jig 100 including a punch 101 and a die 102 is used to form the joint 15. The stacked body of the housing 20 and the main body 12 of the motor mounting member 10 at the joining position 25 is arranged on the die 102. The punch 101 has a tip portion 101a having an outer shape corresponding to the inner shape of the concave portion 15a of the joining portion 15. First, as shown in FIG. 5A, the tip portion 101a of the punch 101 is arranged toward the joining position 25. Subsequently, as shown in FIG. 5B, the front end portion 101a is pushed into the stacked body and pressed. At this time, the main body 12 and the housing 20 of the motor mounting member 10 are plastically deformed, and the tip 101 a of the punch 101 bites into the hole 102 a of the die 102. As a result, the layer of the housing 20 and the layer of the main body 12 of the motor mounting member 10 are deformed along the shape of the hole 102a of the die 102. As a result, as shown in FIG. 5C, a joint 15 having a concave portion 15a that is depressed in the axial direction and inside the housing 20 is formed.

After the joining portion 15 is formed, the stator 40 is shrink-fitted into the housing 20 and fixed by caulking, press-fitting, bonding, or the like. The rotor 30 is arranged radially inside the stator 40.
In the manufacturing method of the motor 1 described above, one motor mounting member is selected from a plurality of motor mounting members having different radial dimensions, and the motor mounting member 10 is fixed to the housing 20. That is, the motor mounting member 10 can be selected according to the motor mounting position of the other member 90. Therefore, the motor 1 can be attached to another member 90 without depending on the radial dimension φ of the housing 20 shown in FIG. Therefore, it is possible to realize a method of manufacturing a motor and a motor that can easily adjust a mounting position on another member 90.

(2nd Embodiment)
A motor according to the second embodiment will be described with reference to FIGS. The motor according to the present embodiment is the same as the motor 1 according to the first embodiment except for the housing 20 and the motor mounting member 10, and therefore some illustration and description are omitted. Also, the same components as those of the motor 1 according to the first embodiment are denoted by the same reference numerals, and the detailed description will be omitted.

  As shown in FIGS. 6 and 7, the bottom portion 23 of the housing 20 according to the present embodiment and the main body portion 12 of the motor mounting member 210 are joined in the axial direction via a joining portion 215. The joints 215 are formed at four joint positions 25 provided on the inner diameter side of the outer periphery of the main body 12 of the motor mounting member 210. The joining positions 25 are provided at equal intervals in the circumferential direction around the central axis C, as in the first embodiment.

  As shown in FIG. 8, each joint portion 215 has a through hole 215c and a curved portion 215a. The through hole 215c passes through the bottom portion 23 of the housing 20 in the axial direction. The curved portion 215a has a shape in which an axial section is bent in a U-shape. Each joint 215 is formed using a predetermined jig (not shown). First, three sides of a portion of the motor mounting member 210 corresponding to the joint position 25 are cut, and the cut portions are inserted into the through holes 215 c to protrude inward in the axial direction of the housing 20. Next, the projecting cut portion is bent and fixed with the outer edge 215e of the through hole 215c interposed therebetween. As a result, the housing 20 and the motor mounting member 210 are joined.

  Also in the motor 1 having the joint 215 according to the present embodiment, similarly to the first embodiment, the joint 215 does not form a portion that protrudes outside the housing 20, so that the other member 90 is damaged when the motor is mounted. Therefore, the influence of the motor mounting member 210 on the size of the motor 1 in the axial direction can be minimized. Also, in the method of manufacturing the motor, similarly to the first embodiment, the motor mounting member 210 can be selected according to the motor mounting position of the other member 90, so that it does not depend on the radial dimension of the housing. A motor can be attached to another member 90.

  The through hole 215c may be provided on the motor mounting member 210 side, and the curved portion 215a may be provided on the housing 20 side. In this case, the curved portion 215a slightly protrudes from the outer end surface 12b of the motor mounting member 210 shown in FIG. 7, but the effect is small.

(Other embodiments)
(1)
In the first and second embodiments, the number and positions of the joints 15 and 215 are not limited to the above examples. The number of the joints 15 and 215 may be two or more. For example, the joints 15 and 215 may be provided at two joint positions 25 sandwiching the central axis C. Alternatively, the joints 15 and 215 may be provided at five or more joint positions 25. In addition, the plurality of joining positions 25 need not be evenly arranged in the circumferential direction, and may be arranged at irregular intervals. Further, the length in the radial direction from the central axis C to each joint position 25 does not need to be constant, and may be different.

(2)
In the first and second embodiments, the method of forming the joints 15 and 215 is not limited to the above example. For example, joining by spot welding may be used.

(3)
The form of the motor 1 is not limited to the first and second embodiments. For example, the motor 1 may be of a type that does not include a bus bar support or a bus bar, and connects the lead of the coil wire 43 to the control board 80.

(4)
An example in which the motor 1 is mounted on the electric power steering device 2 will be described with reference to FIG.

  The electric power steering device 2 is mounted on a steering mechanism of a wheel 912 of an automobile. The electric power steering device 2 is a column-type power steering device that directly reduces the steering force by the power of the motor 1. The electric power steering device 2 includes the motor 1, a steering shaft 914, and an axle 913.

  The steering shaft 914 transmits an input from the steering 911 to an axle 913 having wheels 912. The power of the motor 1 is transmitted to the axle 913 via a ball screw. The motor 1 used in the column-type electric power steering device 2 is provided inside an engine room (not shown). The electric power steering device 2 shown in FIG. 9 is a column type, but may be a rack type.

  The electric power steering device 2 includes a motor 1. For this reason, the electric power steering device 2 having the same effects as the above embodiment can be obtained.

  Here, the electric power steering device 2 is described as an example of the method of using the motor 1, but the method of using the motor 1 is not limited, and the motor 1 can be used in a wide range such as a pump and a compressor.

  The above-described embodiments and modifications are to be considered in all respects as illustrative and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the embodiments described above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

DESCRIPTION OF SYMBOLS 1 ... Motor, 2 ... Electric power steering device, 10, 210 ... Motor mounting member, 11 ... Flange part, 12 ... Body part, 12a ... Second end face, 12b ... Outer end face, 15, 215 ... Joint part, 15a ... Concave part , 17 mounting hole, 18 second center hole, 19 second annular wall portion, 20 housing, 23 bottom portion, 23a first end face, 23b inner end face, 25 joining position, 27 lower bearing Holder, 27a: first center hole, 27b: first annular wall, 28: bearing holder, 30: rotor, 31: shaft, 40: stator, 41: stator core, 42: insulator, 43: coil wire, 50: bus bar Support, 61: bus bar, 71: upper bearing, 72: lower bearing, 80: control board, 90: other members, 100: jig, 101: punch, 101a ... End, 102: die, 102a: hole, 210: motor mounting member, 215a: curved portion, 215c: through hole, 215e: outer edge, 911: steering wheel, 912: wheels, 913: axle, 914: steering shaft, C: Center axis

Claims (13)

A shaft extending along the central axis and having bearings at both axial ends, a rotor fixed to the shaft, a stator arranged radially outside the rotor, and a housing arranged radially outside the stator; A motor mounting member for mounting a motor to another member, the motor mounting member having a main body portion facing one axial end of the housing and a flange portion protruding radially outward from the main body portion, A method of manufacturing a motor comprising:
Select one motor mounting member from the plurality of motor mounting members having different radial dimensions,
An axial end of the housing having a first end surface and a main body of the one motor mounting member having a second end surface facing the first end surface are provided on the first end surface and the second end surface. At two or more joint positions, joint in the axial direction,
Fixing the stator in the housing,
Mounting the rotor in the housing;
A method for manufacturing a motor, including a step. Joining one axial end of the housing and the main body of the one motor mounting member is at least one of welding and swaging.
A method for manufacturing a motor according to claim 1. In the caulking connection, at the two or more bonding positions, one end in the axial direction of the housing and the main body of the one motor mounting member are plastically deformed by being pushed in one axial direction by a jig to form a concave portion. including,
A method for manufacturing a motor according to claim 2. The caulking connection forms a through-hole penetrating in the axial direction at one of the axial end of the housing and one of the main body portions of the one motor mounting member at the two or more joint positions, and the axial end of the housing and In the other of the main body portion of the one motor mounting member, a portion facing the through hole is cut into a U shape, the portion cut into the U shape is curved, and the outer edge of the through hole is sandwiched.
A method for manufacturing a motor according to claim 2. The joining position is
A plurality is provided along the circumferential direction of the housing,
Disposed on the inner diameter side of the outer periphery of the main body of the motor mounting member,
A method for manufacturing a motor according to claim 1. A shaft extending along the central axis and having bearings at both axial ends,
A rotor fixed to the shaft,
A stator arranged radially outside the rotor;
A housing disposed radially outward of the stator and having a first end face at one axial end and a first center hole through which the shaft passes at a radial center of the first end face;
A motor mounting member for mounting a motor to another member, the main body having a second end face axially opposed to the first end face, and extending from an outer periphery of the main body part to a radial outside of the housing. A motor mounting member having a flange portion,
A joining portion that joins one end in the axial direction of the housing and the main body of the motor mounting member in the axial direction, and a joining portion provided on the inner diameter side of the outer periphery of the main body of the motor mounting member,
A motor. The joint portion includes a concave portion that is one side in the axial direction and is depressed inward of the housing.
A motor according to claim 6. The joint is
A through-hole provided in one of the axial direction of the housing and one of the main body of the motor mounting member, and penetrating in the axial direction;
A curved portion which is provided at one end in the axial direction of the housing and the other of the main body of the motor mounting member, and has an axial cross section bent in a U shape and fixed by sandwiching an outer edge of the through hole;
Having,
A motor according to claim 6. One end in the axial direction of the housing has a first annular wall portion surrounding the first center hole and extending inward of the housing from an inner end surface opposite to the first end surface,
The first annular wall portion accommodates at least a portion of the bearing;
A motor according to any one of claims 6 to 8. The main body of the motor mounting member has a second center hole axially facing the first center hole and passing the shaft, and an outer side surrounding the second center hole and opposite to the second end surface. A second annular wall extending from the end surface.
The motor according to claim 6. A shaft extending along the central axis and having bearings at both axial ends,
A rotor fixed to the shaft,
A stator arranged radially outside the rotor;
A housing disposed radially outward of the stator and having a first end face at one axial end and a first center hole through which the shaft passes at a radial center of the first end face;
A motor mounting member for mounting a motor to another member, the main body having a second end face axially opposed to the first end face, and extending from an outer periphery of the main body part to a radial outside of the housing. A motor mounting member having a flange portion,
A joining portion that joins one end in the axial direction of the housing and the main body of the motor mounting member in the axial direction, and is provided on the inner diameter side of the outer periphery of the main body of the motor mounting member, and is provided in the axial direction and the housing A joint including a concave portion recessed inward,
A motor. A shaft extending along the central axis and having bearings at both axial ends,
A rotor fixed to the shaft,
A stator arranged radially outside the rotor;
A housing disposed radially outward of the stator and having a first end face at one axial end and a first center hole through which the shaft passes at a radial center of the first end face;
A motor mounting member for mounting a motor to another member, the main body having a second end face axially opposed to the first end face, and extending from an outer periphery of the main body part to a radial outside of the housing. A motor mounting member having a flange portion,
A joining portion that joins one end in the axial direction of the housing and the main body of the motor mounting member in the axial direction, and a joining portion provided on an inner diameter side of an outer periphery of the main body of the motor mounting member,
With
The joint is
A through hole provided in one end of the housing in the axial direction and one of the main body of the motor mounting member and penetrating in the axial direction,
A curved portion that is provided at one end in the axial direction of the housing and the other of the main body of the motor mounting member, and whose axial cross section is bent into a U-shape and fixed by sandwiching the outer edge of the through hole;
Having,
motor. A motor according to any one of claims 6 to 12,
Electric power steering device.

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