CN214799081U - Rotor and motor - Google Patents

Abstract

The utility model provides a rotor and motor, the utility model discloses a mode of rotor possesses: a shaft rotatable about a central axis extending in an axial direction; a rotor core fixed to the shaft and configured by stacking a plurality of plate members in an axial direction; a magnet fixed to the rotor core; and a fixing member that fixes the magnet to the rotor core. The rotor core has a receiving hole penetrating in the axial direction. The magnet is accommodated in the accommodating hole. The fixing member includes: a base portion that is in contact with a surface on one axial side of the rotor core; and an extension portion extending from the base portion to the other axial side and passing through the receiving hole. The extension part has: a magnet support part which is positioned in the receiving hole and presses the magnet against the inner surface of the receiving hole; and a rotor core support portion that is in contact with the other axial side surface of the rotor core.

Description

Rotor and motor

Technical Field

The utility model relates to a rotor and motor.

Background

Motors having a structure in which magnets are held in holes provided in a rotor core are known. For example, as such a motor, patent document 1 describes a motor for electric power steering.

Patent document 1: japanese patent laid-open publication No. 2019-115121

The rotor core of the motor as described above may be formed by stacking a plurality of plate members. In this case, a part of the laminated plate member may be rolled up. In contrast, if a member pressing the plurality of plate members is attached to the rotor core, the plate members can be prevented from being rolled up. However, in this case, the number of parts of the rotor increases, and the number of assembling steps of the rotor increases. Therefore, there is a problem in that the manufacturing cost of the rotor and the manufacturing cost of the motor increase.

SUMMERY OF THE UTILITY MODEL

In view of the above, it is an object of the present invention to provide a rotor and a motor having a structure that can reduce manufacturing costs.

The utility model discloses a one mode of rotor possesses: a shaft rotatable about a central axis extending in an axial direction; a rotor core fixed to the shaft and configured by stacking a plurality of plate members in an axial direction; a magnet fixed to the rotor core; and a fixing member that fixes the magnet to the rotor core. The rotor core has a receiving hole that penetrates in the axial direction. The magnet is accommodated in the accommodating hole. The fixing member has: a base portion that is in contact with a surface on one axial side of the rotor core; and an extension portion extending from the base portion to the other axial side and passing through the receiving hole. The extension has: a magnet support portion which is positioned in the housing hole and presses the magnet against an inner surface of the housing hole; and a rotor core support portion that is in contact with the other axial side surface of the rotor core.

In the rotor according to the above aspect, the housing hole is provided in a plurality in a circumferential direction around the central axis, the magnet and the extension portion are provided for each of the housing holes, and the base portion extends in the circumferential direction around the central axis and connects the plurality of extension portions.

In the rotor according to the above aspect, the rotor core support portion is a caulked portion obtained by caulking an end portion of the other axial side of the extension portion.

In the rotor of the above-described manner, the fixing member is a single member.

In the rotor of the above aspect, the fixing member is made of a metal plate.

In the rotor according to the above aspect, the base portion is disposed to face one axial side of the magnet, and the rotor core includes a retaining portion disposed to face the other axial side of the magnet.

In the rotor according to the above aspect, the magnet support portion is located radially inward of the magnet and extends in the axial direction, the rotor core support portion protrudes radially outward from an end portion on the other axial side of the magnet support portion, and at least a part of the rotor core support portion is in contact with a surface on the other axial side of the retaining portion.

In the rotor according to the above aspect, the magnet support portion is located radially inward of the magnet and extends in the axial direction, and the rotor core support portion protrudes radially inward from an end portion on the other axial side of the magnet support portion.

In the rotor according to the above aspect, the magnet support portion is located on one side in the radial direction from the magnet and extends in the axial direction, the rotor core support portion protrudes from an end portion on the other side in the axial direction of the magnet support portion to one side in the radial direction, the extension portion has a protruding portion protruding from an end portion on the other side in the axial direction of the magnet support portion to the other side in the radial direction, and the protruding portion covers at least a part of the housing hole from the other side in the axial direction.

The utility model discloses a mode of motor possesses: the above rotor; and a stator facing the rotor with a gap therebetween.

According to the utility model discloses an aspect can reduce the manufacturing cost of rotor and motor.

Drawings

Fig. 1 is a sectional view showing a motor of a first embodiment.

Fig. 2 is a view of the rotor of the first embodiment as viewed from above.

Fig. 3 is a sectional view showing a part of the rotor of the first embodiment, and is a sectional view taken along the line III-III of fig. 2.

Fig. 4 is a perspective view showing a part of the rotor core of the first embodiment.

Fig. 5 is a perspective view showing the fixing member of the first embodiment.

Fig. 6 is a diagram showing a state in the middle of manufacturing the fixing member of the first embodiment.

Fig. 7 is a cross-sectional view showing a part of a rotor according to a modification of the first embodiment.

Fig. 8 is a sectional view showing a part of a rotor of the second embodiment.

Fig. 9 is a perspective view showing a part of a rotor of the third embodiment.

Description of the reference symbols

10. 210, 310, 410: a motor; 12: a stator; 20. 220, 320, 420: a rotor; 21: a shaft; 30. 330 and 430: a rotor core; 31: a plate member; 31a, 331 a: a first plate member (plate member); 31 b: a second plate member (plate member); 33: a receiving hole; 35. 335: an anti-drop part; 40: a magnet; 50. 250, 350, 450: a fixing member; 51. 251: a base; 52. 352, 452: an extension portion; 53. 353, and 2: a magnet support; 54. 354, 454: a rotor core support portion; 456: a protrusion; j: a central axis.

Detailed Description

The Z-axis direction shown in the drawings is a vertical direction in which the positive side is the "upper side" and the negative side is the "lower side". The central axis J shown in each figure is an imaginary line extending in the vertical direction and parallel to the Z-axis direction. In the following description, the axial direction of the center axis J, i.e., the direction parallel to the vertical direction, is simply referred to as the "axial direction", the radial direction about the center axis J is simply referred to as the "radial direction", and the circumferential direction about the center axis J is simply referred to as the "circumferential direction". In the following embodiments, the lower side corresponds to the "one axial side", and the upper side corresponds to the "other axial side".

The vertical direction, the upper side, and the lower side are only names for explaining the arrangement relationship of the respective portions, and the actual arrangement relationship may be an arrangement relationship other than the arrangement relationship indicated by these names.

< first embodiment >

The motor 10 of the present embodiment shown in fig. 1 is an inner rotor type motor. As shown in fig. 1, a motor 10 of the present embodiment includes a housing 11, a rotor 20, a stator 12, a bearing holder 13, and bearings 14 and 15. The housing 11 accommodates therein the rotor 20, the stator 12, the bearing holder 13, and the bearings 14 and 15. The bottom of the housing 11 holds a bearing 14. The bearing holder 13 holds the bearing 15. The bearings 14 and 15 are, for example, ball bearings.

The stator 12 and the rotor 20 are opposed to each other with a gap therebetween. In the present embodiment, the stator 12 is located radially outward of the rotor 20. The stator 12 is annular and surrounds the rotor 20. The stator 12 has a stator core 12a, an insulator 12b, and a plurality of coils 12 c. Although not shown, the stator core 12a has an annular core back surrounding a rotor core 30 described later and a plurality of teeth extending radially inward from the core back. The plurality of coils 12c are attached to the plurality of teeth of the stator core 12a via the insulator 12 b.

The rotor 20 is rotatable about the central axis J. As shown in fig. 2, the rotor 20 includes a shaft 21, a rotor core 30, a magnet 40, and a fixing member 50. The shaft 21 is rotatable about a central axis J extending in the axial direction. The shaft 21 is, for example, a cylindrical shape extending in the axial direction with the center axis J as the center. As shown in fig. 1, the shaft 21 is supported by the bearings 14 and 15 to be rotatable about the center axis J.

Rotor core 30 is a magnetic body. Rotor core 30 is fixed to shaft 21. As shown in fig. 2, rotor core 30 is, for example, substantially cylindrical with center axis J as the center. The rotor core 30 has a center hole 32, a housing hole 33, and a through hole 34. Center hole 32 penetrates rotor core 30 in the axial direction. The central hole 32 is, for example, a circular hole centered on the central axis J. The shaft 21 passes axially through the central bore 32. The shaft 21 is fixed in the central hole 32 by press fitting or the like, for example. Thereby, rotor core 30 is fixed to the outer peripheral surface of shaft 21.

The housing hole 33 penetrates the rotor core 30 in the axial direction. In the present embodiment, the plurality of receiving holes 33 are provided in the circumferential direction around the center axis J. The plurality of receiving holes 33 are arranged at equal intervals in the circumferential direction, for example, over a circumferential range. The receiving holes 33 are provided with, for example, eight. The housing hole 33 is provided at, for example, the radially outer edge portion of the rotor core 30. The housing hole 33 extends linearly in the circumferential direction when viewed in the axial direction, for example. The plurality of housing holes 33 extend along each side of a regular polygon shape centered on the central axis J, for example, when viewed in the axial direction. That is, the eight receiving holes 33 extend along the respective sides of the shape of the octagonal solid centering on the central axis J, for example, when viewed in the axial direction. The housing hole 33 has a substantially rectangular shape when viewed in the axial direction, for example.

The through hole 34 axially penetrates the rotor core 30. The through hole 34 is, for example, a circular hole. The plurality of through holes 34 are provided in the circumferential direction. The plurality of through holes 34 are arranged at equal intervals in a circumferential direction, for example. For example, eight through holes 34 are provided. The through holes 34 are disposed radially inward of the receiving holes 33, respectively. The air flows in the axial direction through the through-hole 34, whereby the rotor 20 can be cooled by the air.

The plurality of through holes 34 include a plurality of large diameter holes 34a and a plurality of small diameter holes 34 b. The large-diameter holes 34a and the small-diameter holes 34b are alternately arranged in the circumferential direction, for example. The large-diameter hole 34a and the small-diameter hole 34b are provided with, for example, four holes. The small-diameter hole 34b has a smaller inner diameter than the large-diameter hole 34 a.

As shown in fig. 3, the rotor core 30 is configured by stacking a plurality of plate members 31 in the axial direction. The plate member 31 is a plate with its plate surface facing in the axial direction. The plate surface of the plate member 31 is perpendicular to the axial direction, for example. Although not shown, the axially adjacent plate members 31 are connected to each other by, for example, partially caulking. The plate member 31 is, for example, an electromagnetic steel plate. In the present embodiment, the plurality of plate members 31 includes one first plate member 31a and a plurality of second plate members 31 b.

In the present embodiment, the first plate member 31a is the uppermost plate member 31 among the plurality of plate members 31. As shown in fig. 4, the first plate member 31a has a retaining portion 35. That is, in the present embodiment, rotor core 30 has retaining portion 35. The stopper 35 projects in a direction perpendicular to the axial direction from an inner edge of an upper end of the receiving hole 33, for example. In the present embodiment, two retaining portions 35 are provided for each receiving hole 33. In each of the housing holes 33, two retaining portions 35 are provided on inner edges of both circumferential ends of the upper end of the housing hole 33. The retaining portion 35 closes a part of the upper opening of the receiving hole 33.

As shown in fig. 2, the stopper portion 35 is disposed to face the upper side of the magnet 40. In each of the housing holes 33, for example, two retaining portions 35 are disposed to face the upper sides of both circumferential end portions of the radially inner end portion of the magnet 40. The lower surface of the retaining portion 35 may be in contact with the upper surface of the magnet 40, or may be axially opposed to the upper surface of the magnet 40 with a gap therebetween.

The second plate member 31b has the same shape as the first plate member 31a except that the stopper portion 35 is not provided. The plurality of plate members 31 constituting the rotor core 30 are all the second plate members 31b except, for example, the first plate member 31a disposed on the uppermost side. As shown in fig. 3, the lower surface 30a of the rotor core 30 is a lower surface of the second plate member 31b disposed on the lowermost side among the plurality of plate members 31. The upper surface 30b of the rotor core 30 is a surface of the plurality of plate members 31 disposed above the uppermost first plate member 31 a. In the present embodiment, the lower surface 30a corresponds to one axial surface of the rotor core 30, and the upper surface 30b corresponds to the other axial surface of the rotor core 30.

Magnet 40 is fixed to rotor core 30 by fixing member 50. The magnet 40 is accommodated in the accommodating hole 33. As shown in fig. 2, in the present embodiment, the magnet 40 is provided for each receiving hole 33. That is, in the present embodiment, a plurality of magnets 40 are provided in the circumferential direction. The magnets 40 are provided with, for example, eight. As shown in fig. 2 and 3, the magnet 40 has, for example, a rectangular parallelepiped shape extending in the axial direction. As shown in fig. 2, the magnet 40 is, for example, a rectangular shape elongated in a direction in which the housing hole 33 in which the magnet 40 is housed extends when viewed in the axial direction. That is, the plurality of magnets 40 are, for example, shaped to extend linearly in the circumferential direction when viewed in the axial direction.

The circumferential end portions of the magnets 40 are disposed apart from the surfaces located on both sides in the circumferential direction, for example, of the inner surfaces of the receiving holes 33. For example, a gap is provided on both sides of each magnet 40 in the circumferential direction. In the present embodiment, each magnet 40 is disposed at a position offset radially outward in each receiving hole 33. As shown in fig. 3, the radially outer side surface of the magnet 40 is in contact with, for example, a radially outer surface of the inner surface of the receiving hole 33. The radially inner surface of the magnet 40 is disposed away from the radially inner surface of the housing hole 33.

The magnet 40 is provided in the axial direction substantially over the entire range of the receiving hole 33 other than the upper end portion provided with the stopper portion 35. The lower surface of the magnet 40 is located at substantially the same position in the axial direction as the lower surface 30a of the rotor core 30, for example. The upper surface of magnet 40 is located below upper surface 30b of rotor core 30, for example. The dimension of the magnet 40 in the axial direction is smaller than the distance in the axial direction between the stopper portion 35 and the base portion 51 described later. At least one of the axial direction between the lower surface of the magnet 40 and the base 51 and the axial direction between the upper surface of the magnet 40 and the retaining portion 35 is provided with a gap. The type of the magnet 40 is not particularly limited.

Fixing member 50 fixes magnet 40 to rotor core 30. The fixing member 50 has a base 51 and an extension 52. As shown in fig. 5, in the present embodiment, the base 51 extends in the circumferential direction around the center axis J. The base portion 51 extends in an arc shape around the center axis J, for example. The circumferential ends of the base 51 are disposed opposite to each other with a slight gap therebetween, for example. The base portion 51 has a shape in which a part of an annular ring is divided in the circumferential direction by a slit when viewed in the axial direction, for example. The base 51 is, for example, a plate with a plate surface facing in the axial direction. The plate surface of the base 51 is perpendicular to the axial direction, for example.

As shown in fig. 2 and 3, in the present embodiment, the base 51 is located below the plurality of receiving holes 33. The base portion 51 closes, for example, the lower opening of each storage hole 33 over substantially the entire range. In the present embodiment, the base 51 is disposed to face the lower side of the magnet 40. The upper surface of the base 51 may be in contact with the lower surface of the magnet 40, or may be opposed to the lower surface of the magnet 40 with a gap therebetween.

As shown in fig. 3, base 51 is in contact with lower surface 30a of rotor core 30. The radially outer edge of the base 51 is located radially outward of the receiving hole 33, for example. The radially outer edge portion of the base portion 51 contacts a portion of the lower surface 30a located radially outward of the receiving hole 33. The radial position of the radially inner edge portion of the base portion 51 is, for example, the same as the radial position of the radially inner edge portion of the receiving hole 33.

The extension 52 extends upward from the base 51 and passes through the receiving hole 33. The extension 52 is inserted into the receiving hole 33 from the lower side, for example, and protrudes upward from the receiving hole 33. As shown in fig. 2, in the present embodiment, the extension portion 52 is provided for each receiving hole 33. That is, in the present embodiment, a plurality of extending portions 52 are provided in the circumferential direction. The plurality of extending portions 52 are arranged at equal intervals in the circumferential direction, for example. The extension portions 52 are provided with, for example, eight. As shown in fig. 5, in the present embodiment, a plurality of extending portions 52 extend upward from the radially inner edge portion of the base portion 51. That is, in the present embodiment, the base 51 connects the plurality of extensions 52.

As shown in fig. 3, the extension portion 52 has a magnet support portion 53 and a rotor core support portion 54. The magnet support portion 53 is positioned in the housing hole 33. In the present embodiment, the magnet support portion 53 is located radially inward of the magnet 40. The magnet support portion 53 is located in a radial gap between the radially inner surface of the magnet 40 and the radially inner surface of the housing hole 33. The radial gap between the radially inner surface of the magnet 40 and the radially inner surface of the receiving hole 33 is larger than the plate thickness of the plate-shaped extension portion 52.

The magnet support portion 53 extends in the axial direction. More specifically, the magnet support portion 53 extends upward from the radially inner edge portion of the base portion 51. The magnet support portion 53 has a plate shape with a plate surface facing in the radial direction. In the present embodiment, the magnet support portion 53 includes a first linear portion 53a, a first connecting portion 53b, a contact portion 53c, a second connecting portion 53d, and a second linear portion 53e in this order from the lower side toward the upper side.

The first straight portion 53a extends linearly from the radially inner edge portion of the base portion 51 directly upward. The lower end of the first straight portion 53a is the lower end of the magnet support portion 53. The radially inner side surface of the first straight portion 53a contacts a radially inner surface of the receiving hole 33. The radially outer side surface of the first straight portion 53a is arranged away from the radially inner side surface of the magnet 40 toward the radially inner side. The first connecting portion 53b extends from an upper end of the first linear portion 53a diagonally upward to a radially outer side. The first connecting portion 53b axially connects the first straight portion 53a and the contact portion 53 c.

The contact portion 53c linearly extends from the upper end of the first connecting portion 53b directly upward. The radially outer surface of the contact portion 53c contacts the radially inner surface of the magnet 40. The radially inner surface of the contact portion 53c is disposed apart from the radially inner surface of the housing hole 33. The axial dimension of the contact portion 53c is larger than the axial dimension of the other portion of the magnet support portion 53, for example. That is, the dimension in the axial direction of the contact portion 53c is larger than, for example, the dimension in the axial direction of the first linear portion 53a, the dimension in the axial direction of the first coupling portion 53b, the dimension in the axial direction of the second coupling portion 53d, and the dimension in the axial direction of the second linear portion 53 e. The second coupling portion 53d extends from the upper end of the contact portion 53c to the radially inner side in an obliquely upward direction. The second coupling portion 53d axially couples the contact portion 53c and the second linear portion 53 e.

The second linear portion 53e linearly extends from the upper end of the second coupling portion 53d directly upward. The upper end of the second linear portion 53e is the upper end of the magnet support portion 53. The radially inner side surface of the second linear portion 53e contacts a radially inner surface of the receiving hole 33. The radially outer side surface of the second linear portion 53e is arranged away from the radially inner side surface of the magnet 40 toward the radially inner side. The dimension in the axial direction of the second linear portion 53e is smaller than the dimension in the axial direction of the first linear portion 53a, for example.

The magnet support portion 53 has a shape in which the first coupling portion 53b and the second coupling portion 53d are provided obliquely with respect to the axial direction, so that the contact portion 53c protrudes radially outward. The first coupling portion 53b and the second coupling portion 53d function as leaf springs, whereby the contact portion 53c can be elastically displaced in the radial direction. Thus, the magnet support portion 53 functions as an elastic body that can be elastically deformed in the radial direction.

In the state where the magnet support portion 53 is housed in the housing hole 33, the contact portion 53c is elastically displaced radially inward with respect to the first linear portion 53a and the second linear portion 53e by being sandwiched between the radially inward surface of the inner surface of the housing hole 33 and the radially inward surface of the magnet 40. That is, the magnet support portion 53 is in a state in which the magnet support portion 53 can apply an elastic force in the radial direction to the member in contact with the magnet support portion 53 in the housing hole 33. Thereby, the magnet support portion 53 applies a force directed radially outward to the magnet 40 via the contact portion 53 c. The magnet 40 is pressed against the radially outer surface of the inner surface of the housing hole 33 by receiving a radially outward force from the magnet support portion 53. Thus, the magnet support portion 53 presses the magnet 40 against the inner surface of the housing hole 33.

In the present embodiment, the rotor core support portion 54 protrudes radially inward from the upper end of the magnet support portion 53. The rotor core support portion 54 is, for example, a plate shape with its plate surface facing in the axial direction. The plate surface of the rotor core support portion 54 is perpendicular to the axial direction, for example. The rotor core support portion 54 is located on the upper side of the rotor core 30. The radially inner end of the rotor core support portion 54 is located radially outward of the through hole 34.

The rotor core support portion 54 contacts the upper surface 30b of the rotor core 30. The lower surface of the rotor core support portion 54 is in contact with, for example, a portion of the upper surface 30b that is located radially inward of the receiving hole 33 and radially outward of the through hole 34. The lower surface of the rotor core support portion 54 contacts, for example, the radially inner portion of the peripheral edge portion of the receiving hole 33 of the upper surface 30 b.

In the present embodiment, the rotor core support portion 54 is a caulked portion in which the upper end portion of the extension portion 52 is caulked. In the present specification, the clinch portion refers to a portion produced by plastically deforming a part of a member by, for example, press working. That is, the rotor core support portion 54 is a portion produced by plastically deforming the upper end portion of the extension portion 52. In the present embodiment, the rotor core support portion 54 is manufactured by bending and plastically deforming an upper end portion of the extension portion 52 radially inward. The rotor core support 54 is radially inwardly caulked with respect to the upper end of the magnet support 53. The fixing member 50 shown in fig. 5 is in a state before the upper end of the extension portion 52 is caulked, that is, before the rotor core support portion 54 is manufactured.

In the present embodiment, the fixing member 50 is a single member. The fixing member 50 is made of, for example, a metal plate. That is, the fixing member 50 is manufactured by, for example, applying machining to a metal plate. The worker or the like who produces the fixing member 50 performs press working or the like on the metal member 150 shown in fig. 6 which is punched out from a metal plate by press working or the like and bends the same, thereby producing the fixing member 50 shown in fig. 5, that is, the fixing member 50 in a state before producing the rotor core support 54.

In the present specification, "operator" includes an operator and a device for performing each operation. Each operation may be performed by an operator, an apparatus, a device, or the like.

As shown in fig. 6, the metal member 150 has a first portion 151 and a plurality of second portions 152. The first portion 151 is a rectangular plate-shaped portion extending linearly. The plurality of second portions 152 are rectangular plate-shaped portions linearly extending from the first portions 151 in a direction perpendicular to a direction in which the first portions 151 extend. The second portion 152 extends in a direction parallel to the plate surface of the first portion 151. The plurality of second portions 152 are arranged at intervals in the direction in which the first portions 151 extend. The plate surface of the first portion 151 and the plate surface of the second portion 152 are parallel to each other.

The first portion 151 is a portion that is curved in an arc shape in a plane parallel to the plate surface of the first portion 151 and becomes the base portion 51. The second portion 152 is a portion that is bent in a direction perpendicular to the plate surface and becomes the extension portion 52. The second portion 152 is bent along, for example, a chain line and a chain double-dashed line shown in fig. 6, and becomes the extension portion 52 before the rotor core support portion 54 is manufactured, that is, the extension portion 52 shown in fig. 5. The direction in which the second portion 152 is bent along the chain line is the opposite direction to the direction in which the second portion 152 is bent along the chain double-dashed line. The operator or the like bends the second portion 152 along the chain line and the chain double-dashed line, and then bends the first portion 151 into an arc shape. When bending the second portions 152, for example, a worker or the like bends the plurality of second portions 152 together.

After the magnet 40 is inserted into each receiving hole 33 of the rotor core 30 from below, the worker or the like inserts each extending portion 52 of the fixing member 50 in the state shown in fig. 5 into each receiving hole 33 from below. The operator or the like inserts the extending portion 52 into the receiving hole 33 until the upper surface of the base portion 51 comes into contact with the lower surface 30a of the rotor core 30. The operator or the like radially inwardly tightens the upper end portion of the extending portion 52 that protrudes upward from the upper opening of the receiving hole 33, and brings the upper end portion into contact with the upper surface 30b of the rotor core 30. Thereby, rotor core support portion 54 contacting upper surface 30b of rotor core 30 is produced, and magnet 40 and fixing member 50 are assembled to rotor core 30. When assembling the magnet 40 and the fixing member 50 to the rotor core 30, an operator or the like may perform each operation by, for example, vertically reversing the posture of the rotor core 30.

According to the present embodiment, fixing member 50 for fixing magnet 40 to rotor core 30 has base 51 in contact with lower surface 30a of rotor core 30 and extension 52 extending upward from base 51 and passing through receiving hole 33. The extension 52 has a magnet support portion 53 that presses the magnet 40 against the inner surface of the housing hole 33, and a rotor core support portion 54 that contacts the upper surface 30b of the rotor core 30. By pressing the magnet 40 against the inner surface of the housing hole 33 via the magnet support portion 53, the magnet 40 can be fixed to the rotor core 30. Further, the base portion 51 is in contact with the lower surface 30a of the rotor core 30, and the rotor core support portion 54 is in contact with the upper surface 30b of the rotor core 30, whereby the fixing member 50 can be prevented from coming off in the axial direction with respect to the rotor core 30. Further, since the rotor core 30 can be pressed from both sides in the axial direction by the base portion 51 and the rotor core support portion 54, the rolling up of a part of the plate member 31 constituting the rotor core 30 can be suppressed.

By providing the base 51 and the rotor core support portion 54 in the fixing member 50 for fixing the magnet 40 to the rotor core 30 in this manner, the fixing member 50 can be used as a member for pressing the plurality of laminated plate members 31, and thus the plate members 31 can be prevented from being rolled up without providing a separate member. Therefore, the plate member 31 can be suppressed from rolling up, and the number of components of the rotor 20 can be suppressed from increasing. This can suppress an increase in the number of assembly steps of the rotor 20, and thus an increase in the number of assembly steps of the motor 10. Therefore, the manufacturing cost of the rotor 20 and the manufacturing cost of the motor 10 can be reduced.

Further, by attaching the fixing member 50 to the rotor core 30, the fixing operation of the magnet 40 to the rotor core 30 and the pressing operation of the stacked plate members 31 can be easily performed. Therefore, for example, as compared with a case where a resin member pressing the magnet 40 and the plate member 31 is manufactured by insert molding in which the rotor core 30 and the magnet 40 are embedded members, the time and man-hours required for fixing the magnet 40 to the rotor core 30 and for pressing the stacked plurality of plate members 31 can be reduced. Therefore, the manufacturing cost of the rotor 20 and the manufacturing cost of the motor 10 can be further reduced.

In addition, according to the present embodiment, the plurality of receiving holes 33 are provided in the circumferential direction around the center axis J. The magnet 40 and the extension 52 are provided for each receiving hole 33. The base 51 extends in the circumferential direction around the center axis J, and connects the plurality of extensions 52. Therefore, each magnet 40 can be fixed to the rotor core 30 by the magnet support portion 53 of each extension portion 52. The plate member 31 can be pressed by the rotor core support portions 54 of the plurality of extending portions 52. Therefore, the plate member 31 can be more appropriately suppressed from rolling up.

Since the plurality of extending portions 52 are connected to each other via the single base portion 51, the plurality of extending portions 52 are mounted to the rotor core 30 together by mounting the single fixing member 50 to the rotor core 30. Therefore, for example, as compared with a case where a plurality of fixing members each having one base portion 51 and one extension portion 52 are provided, workability in attaching the fixing member 50 to the rotor core 30 can be improved, and a work time required for attaching the fixing member 50 to the rotor core 30 can be shortened. Further, the number of steps for manufacturing the fixing member 50 can be reduced as compared with the case where a plurality of fixing members each having one base portion 51 and one extension portion 52 are manufactured. This can reduce the manufacturing cost of the fixing member 50, and can further reduce the manufacturing cost of the rotor 20 and the manufacturing cost of the motor 10.

In addition, according to the present embodiment, the rotor core support portion 54 is a caulked portion obtained by caulking the upper end portion of the extension portion 52. Therefore, by passing the extension portion 52 through the receiving hole 33 and then caulking the upper end portion of the extension portion 52 as described above, the rotor core support portion 54 can be easily and appropriately manufactured. Further, it is easy to accurately bring the rotor core support portion 54 into contact with the upper surface 30b of the rotor core 30. Therefore, the plurality of plate members 31 can be more appropriately pressed.

In addition, according to the present embodiment, the fixing member 50 is a single member. Therefore, the increase in the number of components of the rotor 20 and the number of components of the motor 10 can be further suppressed. In addition, the number of steps for manufacturing the fixing member 50 can be reduced as compared with the case where the fixing member 50 is manufactured by connecting a plurality of members. This can further reduce the manufacturing cost of the rotor 20 and the manufacturing cost of the motor 10.

In addition, according to the present embodiment, the fixing member 50 is made of a metal plate. Therefore, the manufacturing cost of the fixing member 50 can be reduced as compared with a case where the fixing member 50 is manufactured by die casting or the like, for example. This can further reduce the manufacturing cost of the rotor 20 and the manufacturing cost of the motor 10. Furthermore, since the extending portion 52 is plate-shaped, it is easy to calk the upper end portion of the extending portion 52 to manufacture the rotor core support portion 54.

In addition, according to the present embodiment, the base 51 is disposed to face the lower side of the magnet 40. Rotor core 30 has retaining portion 35 disposed to face the upper side of magnet 40. Therefore, the magnet 40 can be sandwiched in the axial direction by the base 51 and the stopper 35. This can prevent the magnet 40 from being axially pulled out of the housing hole 33 and the magnet 40 from being axially displaced. Further, since the magnets 40 can be prevented from being displaced in the axial direction, the axial positions of the plurality of magnets 40 can be easily aligned appropriately, and the range of the magnetic field generated by each magnet 40 can be prevented from being displaced in the axial direction. Therefore, by using the fixing member 50, the rotor 20 having excellent magnetic characteristics can be manufactured at low cost. Further, since the variation in the axial position of the magnet 40 can be suppressed, for example, in the case where a magnetic sensor capable of detecting the magnetic field of the magnet 40 is provided, the variation in the axial distance between the magnet 40 and the magnetic sensor can be suppressed. Therefore, the magnetic field of the magnet 40 can be appropriately detected by the magnetic sensor.

For example, when the rotor core support 54 protrudes radially outward from the upper end of the magnet support 53 when the magnet support 53 is located radially inward of the magnet 40, the rotor core support 54 needs to extend radially outward of the receiving hole 33 in order to bring the rotor core support 54 into contact with the upper surface 30b of the rotor core 30. Therefore, in order to appropriately secure an area where the plate member 31 can be pressed by the rotor core support portion 54, the rotor core support portion 54 needs to have a large radial dimension.

In contrast, according to the present embodiment, the magnet support portion 53 is located radially inward of the magnet 40, and the rotor core support portion 54 protrudes radially inward from the upper end of the magnet support portion 53. Therefore, even if the radial dimension of the rotor core support portion 54 is small, the rotor core support portion 54 is easily brought into contact with the upper surface 30b of the rotor core 30. Accordingly, as compared with the case where the rotor core support portion 54 protrudes radially outward, the radial dimension of the rotor core support portion 54 is reduced, and the area in which the plate member 31 can be pressed by the rotor core support portion 54 is easily secured appropriately. Therefore, the radial dimension of the rotor core support portion 54 is reduced to reduce the manufacturing cost of the fixing member 50, and the plate member 31 is easily appropriately pressed by the rotor core support portion 54.

Further, according to the present embodiment, the dimension in the axial direction of the contact portion 53c is larger than the dimension in the axial direction of the first linear portion 53a, the dimension in the axial direction of the first coupling portion 53b, the dimension in the axial direction of the second coupling portion 53d, and the dimension in the axial direction of the second linear portion 53 e. Therefore, the axial dimension of the contact portion 53c can be made large. This can increase the area of the magnet support portion 53 in contact with the magnet 40 in the housing hole 33. Therefore, a force directed radially outward can be appropriately applied to the magnet 40 via the contact portion 53c, and the magnet 40 can be appropriately fixed in the housing hole 33 by the magnet support portion 53.

In addition, according to the present embodiment, the contact portion 53c is a portion provided at a position closer to the base portion 51 than the second coupling portion 53d and the second linear portion 53e in the magnet support portion 53. That is, the contact portion 53c is provided on the side closer to the base portion 51 than the upper end portion of the magnet support portion 53. Therefore, for example, when the extension portion 52 starts to be inserted into the receiving hole 33 from below, the upper end of the extension portion 52 is less likely to contact the magnet 40, as compared with the case where the contact portion 53c is provided at the upper end of the magnet support portion 53. This facilitates passage of the extension 52 through the receiving hole 33. Therefore, the fixing member 50 can be more easily attached to the rotor core 30. In particular, in the present embodiment, the upper end portion of the magnet support portion 53 is provided with a second linear portion 53e linearly extending in the axial direction, and a second coupling portion 53d extending obliquely with respect to the axial direction is provided between the second linear portion 53e and the contact portion 53c in the axial direction. Therefore, when the extension portion 52 is inserted into the receiving hole 33 from below, the second linear portion 53e is easily inserted from the opening below the receiving hole 33. Further, the second coupling portion 53d extending obliquely facilitates elastic displacement of the contact portion 53c in the radial direction, and facilitates entry of the contact portion 53c between the radially inner surface of the housing hole 33 and the radially inner surface of the magnet 40.

Further, according to the present embodiment, the magnets 40 are pressed against the radially outer side surfaces in the receiving holes 33 by the magnet support portions 53. Therefore, the magnets 40 can be positioned in the radial direction by the radially outer side surfaces in the receiving holes 33. This allows the radial positions of the magnets 40 to be appropriately aligned regardless of the accuracy of work by an operator or the like. That is, the radial position of each magnet 40 can be suppressed from being displaced. Therefore, the magnetic characteristics of the rotor 20 can be improved, and the quality of the motor 10 such as the output torque can be improved. Further, vibration and an offset load due to a centrifugal force generated when the rotor 20 rotates can be reduced. Therefore, the load on the bearings 14 and 15 supporting the rotor 20 can also be reduced. This can improve the life of the motor 10. Further, by using the fixing member 50, it is difficult to generate variation in the radial position of the magnet 40 when the rotor 20 is assembled, and therefore variation in the magnetic characteristics of the rotor 20 can be suppressed. This can suppress the occurrence of variations in the quality of the motor 10 such as the output torque.

(modification of the first embodiment)

In the rotor 220 of the motor 210 shown in fig. 7, the base 251 of the fixing member 250 has a base main body 251a and a folded portion 255. The base body 251a has the same shape as the base 51 described above. The folded portion 255 protrudes downward from the radially inner edge portion of the base main body 251a, and is folded inward and upward in the radial direction so as to be connected to the lower end portion of the magnet support portion 53. The folded-back portion 255 is produced, for example, by bending the second portion 152 of the metal member 150 shown in fig. 6 from the root portion in a direction perpendicular to the plate surface with respect to the first portion 151, and then folding back the second portion 152 in the opposite direction. The other structure of the motor 210 may be the same as that of the motor 10 described above.

According to the present modification, by providing the folded-back portion 255, the rigidity of the connecting portion between the base portion 251 and the extending portion 52 can be improved. Therefore, the extended portion 52 is less likely to be displaced with respect to the base portion 251, and the state in which the magnet 40 and the plate member 31 are appropriately pressed by the magnet support portion 53 and the rotor core support portion 54 of the extended portion 52 can be easily maintained. In addition, when the fixing member 250 is made of a metal plate, even if the metal plate is thin, the rigidity of the connecting portion between the base portion 251 and the extending portion 52 is easily ensured. Therefore, the thickness of the metal plate used to manufacture the fixing member 250 can be reduced. This can further reduce the manufacturing cost of the fixing member 250. Therefore, the manufacturing cost of the rotor 220 and the manufacturing cost of the motor 210 can be further reduced. Further, since the fixing member 250 can be reduced in weight by reducing the thickness of the metal plate, the rotor 220 and the motor 210 can be reduced in weight.

Further, for example, in a configuration in which the magnet 40 can be inserted from the opening on the upper side of the housing hole 33, in the case where the magnet 40 is inserted from the upper side into the housing hole 33 after the fixing member 250 is attached to the rotor core 30, even if the magnet 40 is drawn into the housing hole 33 by magnetic force and collides with the base portion 251 from the upper side, the base portion 251 can be suppressed from being deformed with respect to the extension portion 52. This can suppress the occurrence of positional deviation of the magnet 40.

< second embodiment >

As shown in fig. 8, in the rotor 320 of the motor 310 of the present embodiment, the rotor core 330 has a shape of the first plate member 331a different from that of the rotor core 30 of the first embodiment. The retaining portion 335 of the first plate member 331a projects radially inward from the radially outer inner surface of the upper end of the receiving hole 33. The retaining portion 335 covers the entire upper opening of the receiving hole 33 except for the radially inner end portion. In the present embodiment, the portion of the receiving hole 33 exposed to the upper side of the first plate member 331a has a slit shape having a width larger than the plate thickness of the metal plate constituting the fixing member 350. In the present embodiment, the retaining portion 335 covers the entire upper side of the magnet 40, for example.

In the fixing member 350 of the present embodiment, the rotor core supporting portion 354 of the extending portion 352 protrudes radially outward from the upper end of the magnet supporting portion 353. At least a part of the rotor core support portion 354 contacts the upper surface of the retaining portion 335. Thereby, the first plate member 331a can be pressed from above by the rotor core support portion 354. Therefore, the plurality of plate members 31 constituting the rotor core 330 can be suppressed from being rolled up. In the present embodiment, the rotor core support portion 354 is substantially entirely in contact with the upper surface of the retaining portion 335. The other structure of the motor 310 is the same as that of the motor 10 of the first embodiment. In addition, the rotor core support portion 354 may contact the upper surface of the retaining portion 335 in any manner. The rotor core support portion 354 and the retaining portion 335 may be point-contacted, for example.

According to the present embodiment, the rotor core support portion 354 protrudes radially outward from the upper end of the extension portion 352. Therefore, when the through hole 34 is provided radially inward of the receiving hole 33, the rotor core support portion 354 does not close the through hole 34 even if the radial dimension of the rotor core support portion 354 is increased. This prevents the air flowing through the through hole 34 from being blocked by the rotor core support portion 354. Therefore, air can be appropriately flowed in the through-hole 34, and the rotor 320 can be appropriately cooled.

< third embodiment >

As shown in fig. 9, in the rotor 420 of the motor 410 of the present embodiment, the rotor core 430 does not have the first plate member 31a unlike the first embodiment. The plurality of plate members 31 constituting the rotor core 430 include, for example, only the second plate member 31 b. Unlike the first embodiment, the rotor core 430 does not include the retaining portion 35.

The upper end of the extending portion 452 of the fixing member 450 of the present embodiment is divided into two at intervals in the circumferential direction. One of the upper end portions of the two-bifurcated extending portion 452 is a rotor core support portion 454. The rotor core support 454 protrudes radially inward from the upper end of the magnet support 53. The rotor core support portion 454 is, for example, a caulking portion in which an upper end portion of the extension portion 452 is caulked radially inward. The rotor core support portion 454 contacts the upper surface of the rotor core 430. In the present embodiment, the upper surface of the rotor core 430 is the upper surface of the second plate member 31b located on the uppermost side among the plurality of plate members 31.

The other of the upper end portions of the bifurcated extending portions 452 is a protruding portion 456 that protrudes radially outward from the upper end portion of the magnet support portion 53. That is, in the present embodiment, the extension portion 452 has the protruding portion 456. The projection 456 is, for example, a caulking portion in which an upper end portion of the extension 452 is caulked radially outward.

The projection 456 covers at least a part of the receiving hole 33 from the upper side. In the present embodiment, the protruding portion 456 covers a part of the receiving hole 33 from the upper side. The protrusion 456 is disposed to face the upper side of the magnet 40. The lower surface of the projection 456 may be in contact with the upper surface of the magnet 40, or may face the upper surface of the magnet 40 with a gap therebetween. In the present embodiment, the upper surface of magnet 40 and the upper surface of rotor core 430 are arranged at the same position in the axial direction. Other structures of the motor 410 may be the same as those of the motors of the above embodiments. In the present embodiment, the radially inner side corresponds to the "one radial side", and the radially outer side corresponds to the "other radial side".

According to the present embodiment, the extension portion 452 has the protruding portion 456 covering at least a part of the receiving hole 33 from the upper side. Therefore, even if the rotor core 430 is not provided with the stopper 35, the magnet 40 can be prevented from being pulled out upward from the housing hole 33 by the protrusion 456. When the projection 456 is used as a caulking portion, the projection 456 is easily brought into proper contact with the upper surface of the magnet 40. Therefore, the magnet 40 can be more appropriately held in the axial direction.

In the case where the projection 456 is a caulking portion, the upper opening of the receiving hole 33 can be set in a state where the magnet 40 can be inserted before the projection 456 is caulked. Therefore, for example, the following assembly method can be adopted: one of the upper ends of the bifurcated extensions 452 is swaged to form a rotor core support 454, and after the fixing member 450 is attached to the rotor core 430, the magnet 40 is inserted from above the receiving hole 33. This can improve the degree of freedom of the method of assembling the rotor 420.

The present invention is not limited to the above embodiment, and other configurations can be adopted within the scope of the technical idea of the present invention. The fixing member may be configured by coupling a plurality of members. The material constituting the fixing member is not particularly limited. The fixing member may be made of resin. The fixing member may be manufactured by a method of molding a material by pouring the material into a mold, such as die casting. The fixing member may be provided in plurality. In this case, each fixing member may also have a base portion and at least one extension portion. The number of extensions that one fixing member has is not particularly limited. A fixing part may also have only one extension. The shape of the base is not particularly limited. The base portions may be circular rings joined over the entire circumference.

The magnet support portion may be disposed at any position relative to the magnet in the housing hole. The magnet support portion may be located radially outward of the magnet in the housing hole, or may be located adjacent to the magnet in the circumferential direction in the housing hole. When the magnet support portion is located radially outward of the magnet, the magnet support portion presses the magnet against a radially inward surface of the inner surface of the housing hole, for example. When the magnet support portion is located on one circumferential side of the magnet, the magnet support portion presses the magnet against a surface located on the other circumferential side of the inner surface of the housing hole, for example. For example, in the first embodiment, the magnet support portion 53 may be disposed in any one of the air gaps provided on both sides of the magnet 40 in the circumferential direction. The shape of the magnet support portion is not particularly limited as long as the magnet can be pressed against the inner surface of the housing hole.

When the magnet support portion is located radially outward of the magnet, the rotor core support portion may protrude radially outward from the other axial end of the magnet support portion, and the extension portion may have a protrusion protruding radially inward from the other axial end of the magnet support portion. In this configuration, at least a part of the housing hole is covered by the protruding portion from the other axial side, and the magnet can be prevented from being pulled out of the housing hole by the protruding portion, as in the third embodiment. In this case, the radially outer side corresponds to the "one radial side", and the radially inner side corresponds to the "other radial side".

The protrusion provided in the extension portion may be in contact with the other axial side surface of the rotor core. For example, in the third embodiment, the protruding portion 456 may further protrude radially outward and contact a portion of the upper surface of the rotor core 430 that is located radially outward of the receiving hole 33. In this case, the protrusion 456 can also press the plate member 31 while preventing the magnet 40 from being pulled out upward. Therefore, the plate member 31 can be more appropriately pressed.

The rotor core support portion may be any shape as long as it is in contact with the surface of the other side in the axial direction of the rotor core. The rotor core support portion may be at least partially in contact with the other axial surface of the rotor core. The rotor core support portion may not be a calking portion. In this case, the rotor core support portion may be a portion molded by die casting, for example. The rotor core support portion may be provided with two or more than two in one extending portion. The fixing member may have an extension portion without the rotor core support portion. For example, in the first embodiment, some of the plurality of extending portions 52 may have no rotor core support portion 54 and may be configured as extending portions 52.

The shape of the magnet is not particularly limited. The number of magnets is not particularly limited. Only one magnet may be provided. In this case, the magnet may be ring-shaped so as to surround the central axis. The material of the plurality of plate members constituting the rotor core is not particularly limited. The plurality of plate members may also include three or more plate members having different shapes. The number of plate members is not particularly limited as long as two or more plate members are provided. In the fourth embodiment, the rotor core 430 may have a retaining portion.

The shape of the housing hole provided in the rotor core as viewed in the axial direction is not particularly limited. The rotor core may also be provided with a pair of receiving holes that extend in a direction away from each other in the circumferential direction as viewed in the axial direction, as facing radially outward. In this case, a plurality of pairs of the pair of receiving holes may be provided in the circumferential direction. In this case, the pair of receiving holes may have a substantially rectangular shape extending obliquely with respect to the radial direction when viewed in the axial direction. In this case, the pair of receiving holes may be arranged in a V shape that is open to the outside in the radial direction when viewed in the axial direction. The pair of receiving holes may extend in a direction approaching each other in the circumferential direction as they go radially outward, when viewed in the axial direction. In this case, the pair of receiving holes may be arranged in a V shape that is open radially inward when viewed in the axial direction.

The use of the motor to which the present invention is applied is not particularly limited. The motor may be mounted on a vehicle, for example, or may be mounted on a device other than a vehicle. As described above, the structures described in this specification can be appropriately combined within a range not inconsistent with each other.

Claims (10)

1. A rotor, characterized in that,

the rotor is provided with:

a shaft rotatable about a central axis extending in an axial direction;

a rotor core fixed to the shaft and configured by stacking a plurality of plate members in an axial direction;

a magnet fixed to the rotor core; and

a fixing member that fixes the magnet to the rotor core,

the rotor core has a receiving hole penetrating in the axial direction,

the magnet is received in the receiving hole,

the fixing member has:

a base portion that is in contact with a surface on one axial side of the rotor core; and

an extension portion extending from the base portion toward the other axial side, passing through the receiving hole,

the extension has:

a magnet support portion which is positioned in the housing hole and presses the magnet against an inner surface of the housing hole; and

and a rotor core support portion that is in contact with the other axial surface of the rotor core.

2. The rotor of claim 1,

the housing hole is provided in plurality along a circumferential direction around the central axis,

the magnet and the extension portion are provided for each of the receiving holes,

the base extends in a circumferential direction around the central axis and connects the plurality of extensions.

3. The rotor of claim 1 or 2,

the rotor core support portion is a caulked portion obtained by caulking an end portion of the other axial side of the extension portion.

4. The rotor of claim 1 or 2,

the securing member is a single member.

5. The rotor of claim 4,

the fixing member is made of a metal plate.

6. The rotor of claim 1 or 2,

the base portion is disposed to face one axial side of the magnet,

the rotor core has a retaining portion disposed opposite the other axial side of the magnet.

7. The rotor of claim 6,

the magnet support portion is located radially inward of the magnet and extends in the axial direction,

the rotor core support portion protrudes radially outward from an end portion on the other axial side of the magnet support portion, and at least a part of the rotor core support portion is in contact with a surface on the other axial side of the retaining portion.

8. The rotor of claim 1 or 2,

the magnet support portion is located radially inward of the magnet and extends in the axial direction,

the rotor core support portion protrudes radially inward from the other end portion in the axial direction of the magnet support portion.

9. The rotor of claim 1 or 2,

the magnet support portion is located on one side in the radial direction of the magnet and extends in the axial direction,

the rotor core support portion protrudes from the end portion on the other axial side of the magnet support portion toward one radial side,

the extension portion has a protruding portion protruding from an end portion of the other side in the axial direction of the magnet support portion to the other side in the radial direction,

the protruding portion covers at least a part of the receiving hole from the other axial side.

10. A motor is characterized in that a motor is provided,

the motor includes:

the rotor of any one of claims 1 to 9; and

and a stator facing the rotor with a gap therebetween.

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