Fixing method of resolver rotor, and fixing structure of resolver rotor

Abstract

To provide a fixing method of a resolver rotor and a fixing structure of the resolver rotor, capable of increasing slip-off load of a resolver rotor in an axial direction in a configuration of the resolver rotor fixed to a motor rotor by swaging.SOLUTION: A fixing method of a resolver rotor 1 includes the steps of: engaging a protrusion 10 of the resolver rotor 1 protruding radially inward with a groove 20a of a fixing portion 20 that is provided on a motor rotor 2 and to which the resolver rotor 1 is fixed; and deforming the groove 20a so that a distance D5 between inner side surfaces 23 on a second end surface 20b side of the groove 20a is reduced, by applying a load from a first direction to a portion 20c near the groove 20a in the second end surface 20b that is on the first direction side from a first end surface 1a of the resolver rotor 1 on the first direction side (X1 direction side), which is one side in an axial direction of the motor rotor 2 of the fixing portion 20, to swage the resolver rotor 1.SELECTED DRAWING: Figure 10

Description

Technical Field

[0001] The present invention relates to a method for fixing a resolver rotor and a fixing structure of a resolver rotor.

Background Art

[0002] Conventionally, a method for fixing a resolver rotor to a motor rotor has been known (see, for example, Patent Document 1).

[0003] Patent Document 1 discloses a motor assembly in which a rotation angle sensor including a sensor rotating member is caulked to an output side rotating member to fix the rotation angle sensor to the output side rotating member. The sensor rotating member described in Patent Document 1 includes a protrusion protruding inward in the radial direction. Further, the output side rotating member disclosed in Patent Document 1 is provided with a groove portion that engages with a protrusion provided on the sensor rotating member. In the configuration disclosed in Patent Document 1, when fixing the sensor rotating member to the output side rotating member, a load is applied to both sides of the protrusion in the circumferential direction of the output side rotating member in a state where the protrusion is engaged with the groove portion, thereby forming a regulating portion. The regulating portion disclosed in Patent Document 1 is configured to regulate the circumferential movement (rotation) of the sensor rotating member by abutting against the protrusion from both sides in the circumferential direction.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] However, the restricting portion formed in the motor assembly described in Patent Document 1 restricts the circumferential movement of the resolver rotor by abutting against the protrusion (projecting portion) of the sensor rotating member (resolver rotor) only from the circumferential direction. Therefore, although the restricting portion disclosed in Patent Document 1 restricts the movement (rotation) of the resolver rotor in the circumferential direction, the pull-out load of the resolver rotor in the axial direction becomes small. Accordingly, in a configuration in which the resolver rotor is fixed by caulking the resolver rotor to the motor rotor, it is desired to increase the pull-out load of the resolver rotor in the axial direction.

[0006] The present invention has been made to solve the above-described problems, and one object of the present invention is to provide a method for fixing a resolver rotor and a fixing structure for a resolver rotor that can increase the pull-out load in the axial direction of the resolver rotor in a configuration in which the resolver rotor is fixed by caulking the resolver rotor to the motor rotor.

Means for Solving the Problems

[0007] In order to achieve the above object, a method for fixing a resolver rotor according to a first aspect of the present invention is a method for fixing a resolver rotor to a motor rotor, the method including: engaging a protruding portion of the resolver rotor protruding inward in the radial direction with a groove portion of a fixing portion provided on the motor rotor and to which the resolver rotor is fixed; and deforming the groove portion by applying a load from a first direction to a portion near the groove portion on a second end surface on the first direction side of the resolver rotor, which is on the first direction side, which is one side in the axial direction of the motor rotor, of the fixing portion in a state where the protruding portion is engaged with the groove portion, so that the distance between inner surfaces on the second end surface side of the groove portion becomes smaller, thereby caulking the resolver rotor.

[0008] In the method for fixing a resolver rotor according to the first aspect of the present invention, as described above, in a state where the protruding portion is engaged with the groove portion, a load is applied from the first direction to a portion near the groove portion on the second end face on the first direction side of the resolver rotor, which is one axial direction side of the motor rotor, among the fixing portions. By deforming the groove portion so that the distance between the inner side faces on the second end face side of the groove portion becomes smaller, the step of caulking the resolver rotor is included. As a result, in a state where the inner side faces on the second end face side of the groove portion are in contact with both side faces of the protruding portion, and the inner side faces on the second end face side of the groove portion can be brought into contact with the first end face of the resolver rotor from the first direction side. Therefore, it is possible to restrict the movement of the resolver rotor in the first direction while restricting the movement (rotation) of the resolver rotor in the circumferential direction by the inner side faces on the second end face side of the groove portion. As a result, compared with a configuration in which the movement of the resolver rotor is restricted by abutting only on both sides in the circumferential direction against the protruding portion of the resolver rotor, the axial pull-out load of the resolver rotor can be increased.

[0009] In the method for fixing a resolver rotor according to the first aspect described above, preferably, in the step of caulking the resolver rotor, by applying a load to a portion near the groove portion and a portion other than the portion near the groove portion on the second end face, the resolver rotor is simultaneously caulked at predetermined intervals in the circumferential direction.

[0010] With this configuration, the portion near the groove portion and the portion other than the portion near the groove portion on the second end face can be caulked by a single caulking step. Therefore, compared with a configuration in which the portion near the groove portion and the portion other than the portion near the groove portion are caulked by different steps, the number of working steps can be reduced. As a result, productivity can be improved.

[0011] In the configuration in which the resolver rotor is simultaneously caulked at predetermined intervals in the circumferential direction, preferably, in the step of caulking the resolver rotor, a load is applied to both sides in the circumferential direction of the groove portion near the groove portion with which the protruding portion is engaged on the second end face, thereby caulking the resolver rotor.

[0012] With such a configuration, by deforming the portions on both sides of the circumferential groove portion of the second end face by a load, the portions on both sides of the circumferential groove portion of the second end face can be brought into contact with the protruding portion of the resolver rotor from the first direction side. Therefore, the movement of the resolver rotor in the axial direction can be restricted by the portions on both sides in the circumferential direction of the second end face. As a result, compared with the configuration in which a load is applied only to one side portion of the circumferential groove portion of the second end face, the pull-out load of the resolver rotor can be made even larger.

[0013] In the configuration of caulking the resolver rotor by applying a load to the portions on both sides of the circumferential groove portion, preferably, the resolver rotor has a first wall thickness portion and a second wall thickness portion having a larger wall thickness in the radial direction than the first wall thickness portion, and in the process of caulking the resolver rotor, the resolver rotor is caulked by applying a load to the portion of the second end face corresponding to the second wall thickness portion of the resolver rotor.

[0014] Here, the resolver detects the rotation angle and / or rotational speed of the motor rotor that rotates together with the resolver rotor based on the change in reactance between the resolver rotor and the resolver stator provided outside the resolver rotor. Further, in order to improve the detection accuracy of the rotation angle and / or rotational speed, the resolver is provided with a first thickness portion and a second thickness portion having different wall thicknesses from each other in the radial direction. When the first thickness portion and the second thickness portion are provided on the resolver rotor, if the difference in wall thickness between the first thickness portion and the second thickness portion in the radial direction becomes small, it approaches the shape of a resolver in which there are no thickness portions with different wall thicknesses from each other, so the detection accuracy of the rotation angle and / or rotational speed decreases. Therefore, as described above, if the resolver rotor is configured to be caulked by applying a load to the portion corresponding to the second thickness portion, even when the resolver rotor is deformed along with the deformation of the fixing portion, the resolver rotor can be deformed so that the difference in wall thickness between the first thickness portion and the second thickness portion in the radial direction becomes large. As a result, when fixing the resolver rotor having the first thickness portion and the second thickness portion to the motor rotor, it is possible to suppress a decrease in the detection accuracy of the rotation angle and / or rotational speed.

[0015] Further, the fixing structure of the resolver rotor according to the second aspect of the present invention includes a motor rotor and a resolver rotor fixed to the motor rotor on the outer side in the radial direction of the motor rotor. The resolver rotor has a protruding portion protruding toward the inner side in the radial direction. The motor rotor has a fixing portion to which the resolver rotor is fixed. The fixing portion has a groove portion into which the protruding portion is engaged. The fixing portion is caulked from the first direction to a portion near the groove portion on the second end face on the first direction side, which is on the first direction side of the first end face of the resolver rotor on the first direction side, which is one side in the axial direction of the motor rotor, in a state where the protruding portion is engaged with the groove portion, so that the distance between the inner surfaces on the second end face side of the groove portion is deformed to become small, and includes a first caulking portion for fixing the resolver rotor from the first direction.

[0016] In the fixing structure of the resolver rotor according to the second aspect of the present invention, as described above, in a state where the protruding portion is engaged with the groove portion, the fixing portion is caulked from the first direction against the portion near the groove portion on the second end face on the first direction side, which is the first direction side of the resolver rotor on one axial side of the motor rotor, of the fixing portion. As a result, the distance between the inner surfaces on the second end face side of the groove portion is deformed to become smaller, and the first caulking portion for fixing the resolver rotor from the first direction is included. Thereby, similarly to the method of fixing the resolver rotor according to the first aspect, it is possible to provide a fixing structure of the resolver rotor capable of increasing the axial pull-out load of the resolver rotor.

[0017] Further, in the fixing structure of the resolver rotor according to the second aspect, preferably, the first caulking portion includes a first deformed portion deformed inward of the groove portion in the circumferential direction. The first deformed portion is deformed inward of the groove portion in the circumferential direction so as to contact the first end face from the first direction side and to contact the side surfaces of the protruding portion from both sides in the circumferential direction, thereby fixing the resolver rotor.

[0018] With this configuration, since the first deformed portion contacts the first end face from the first direction side and contacts the side surfaces of the protruding portion from both sides in the circumferential direction, it is possible to easily restrict the axial movement and circumferential movement (rotation) of the resolver rotor.

[0019] Further, in the configuration in which the first caulking portion includes the first deformed portion, and the first deformed portion contacts the first end face from the first direction side and fixes the resolver rotor in a state of contacting the side surface of the protruding portion, preferably, the fixing portion is caulked from the first direction side against the portion other than the portion near the groove portion, which is separated from the portion near the groove portion on the second end face by a predetermined interval in the circumferential direction, so as to further include a second caulking portion for fixing the resolver rotor together with the first caulking portion.

[0020] With such a configuration, the first caulking portion and the second caulking portion can be formed simultaneously. Therefore, compared with a lattice in which the first caulking portion and the second caulking portion are formed separately, the number of working steps can be reduced. As a result, a fixed structure of a resolver rotor capable of improving productivity can be provided.

[0021] In a configuration in which the fixing portion further includes a second caulking portion, preferably, the resolver rotor has a first wall thickness portion and a second wall thickness portion having a larger wall thickness in the radial direction than the first wall thickness portion, and the first caulking portion and the second caulking portion are provided at portions corresponding to the second wall thickness portion of the resolver rotor.

[0022] With such a configuration, even when the resolver rotor is deformed when forming the first caulking portion and the second caulking portion, the resolver rotor can be deformed in a direction in which the wall thickness in the radial direction between the first wall thickness portion and the second wall thickness portion increases. As a result, even when the resolver rotor is fixed by the first caulking portion and the second caulking portion, it is possible to suppress a decrease in the detection accuracy of the rotation angle and / or the rotation speed.

[0023] (Additional item 1) In the method for fixing a resolver rotor according to the first aspect, preferably, the portion of the second end face near the groove portion on the first direction side and the portion of the second end face other than the portion near the groove portion on the first direction side are equal in position in the axial direction.

[0024] With such a configuration, since the positions of the portion near the groove portion of the second end face and the portion other than the portion near the groove portion are equal to each other in the axial direction, when applying a load simultaneously from the first direction side to the portion near the groove portion of the second end face and the portion other than the portion near the groove portion, it is possible to easily apply loads of equal magnitude to both the portion near the groove portion and the portion other than the portion near the groove portion.

[0025] (Additional item 2) In a configuration where the resolver rotor is caulked by applying a load to portions on both sides of the circumferential groove portion, preferably, in the step of caulking the resolver rotor, a load is applied to portions on both sides of the groove portion on the second end face by a punch member having two abutting portions.

[0026] With this configuration, a load can be applied to each of the portions on both sides of the circumferential groove portion by the two abutting portions. As a result, the positions on both sides of the circumferential groove portion can be easily caulked.

[0027] (Additional item 3) In the step of caulking the resolver rotor, a load is applied to portions on both sides of the groove portion on the second end face by a punch member having a single abutting portion.

[0028] With this configuration, both sides of the groove portion on the second end face can be deformed by the single abutting portion. As a result, it becomes possible to apply a load to the portion near the groove portion and the portion other than near the groove portion without changing the shape of the abutting portion, so that the complexity of the shape of the punch member can be suppressed.

[0029] (Additional item 4) Further, in the fixing structure of the resolver rotor according to the second aspect, preferably, the second caulking portion includes a second deformed portion that deforms outward in the radial direction, and the second deformed portion is provided so as to fix the resolver rotor in a state of abutting against the first end face of the resolver rotor from the first direction side and abutting against the inner peripheral surface of the resolver rotor from the inner side in the radial direction.

[0030] With this configuration, while increasing the radial size of the second deformed portion, it is possible to abut against the first end face from the first direction side. As a result, the second deformed portion can function as a retaining means for the resolver rotor.

Effect of the Invention

[0031] According to the present invention, as described above, in a configuration in which the resolver rotor is fixed by caulking it to the motor rotor, it is possible to provide a method for fixing the resolver rotor and a fixing structure for the resolver rotor that can increase the axial pull-out load of the resolver rotor.

Brief Description of the Drawings

[0032]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Figure 18

Figure 19

Mode for Carrying Out the Invention

[0033] Hereinafter, an embodiment of the present invention will be described with reference to the drawings.

[0034] [This Embodiment] With reference to FIGS. 1 to 14, a method of fixing a resolver rotor 1 and a configuration of a fixing structure 100 of the resolver rotor 1 according to an embodiment of the present invention will be described. The method of fixing the resolver rotor 1 and the fixing structure 100 of the resolver rotor 1 are used when fixing a resolver, which is a rotation angle sensor, to a motor rotor 2. The resolver is attached to a drive device (motor) used in an electric vehicle, a hybrid vehicle, or the like. That is, the method of fixing the resolver rotor 1 according to the present embodiment is a method of fixing the resolver rotor 1 to the motor rotor 2.

[0035] (Overall Configuration of Fixing Structure of Resolver Rotor) As shown in FIG. 1, the fixing structure 100 of the resolver rotor 1 includes a motor rotor 2 and a resolver rotor 1 fixed to the motor rotor 2 on the outer side in the radial direction of the motor rotor 2. The resolver rotor 1 fixed to the motor rotor 2 rotates about the axis 90 together with the motor rotor 2. The detailed configuration of the resolver rotor 1 will be described later. In the present embodiment, the direction in which the motor rotor 2 extends is defined as the X direction. Also, of the X direction, one direction is defined as the X1 direction and the other direction is defined as the X2 direction. Also, two directions orthogonal to each other in the plane orthogonal to the X direction are defined as the Y direction and the Z direction. Of the Y direction, one direction is defined as the Y1 direction and the other direction is defined as the Y2 direction. Also, of the Z direction, one direction is defined as the Z1 direction and the other direction is defined as the Z2 direction. Note that the X1 direction is an example of the "first direction" in the claims.

[0036] The motor rotor 2 has a fixing portion 20 to which the resolver rotor 1 is fixed. Also, in the present embodiment, the motor rotor 2 has a positioning portion 21 that determines the position of the resolver rotor 1 in the X direction. The resolver rotor 1 is fixed to the motor rotor 2 by being fixed by the fixing portion 20 in a state where the positioning in the X direction is performed by the positioning portion 21. The fixing portion 20 is provided on the X1 direction side of the first end face 1a on the X1 direction side of the resolver rotor 1 in the motor rotor 2. The detailed configuration of the fixing portion 20 will be described later. Also, the positioning portion 21 is a protruding portion that protrudes radially from the motor rotor 2 and has an outer diameter D1 that is larger than the inner diameter D2 (see FIG. 2) of the resolver rotor 1.

[0037] (Configuration of resolver rotor) As shown in FIG. 2, the resolver rotor 1 has an opening 1b. That is, the resolver rotor 1 has an annular shape. The motor rotor 2 (see FIG. 1) is inserted through the opening 1b. The inner diameter D2 of the resolver rotor 1 is smaller than the outer diameter D1 of the positioning portion 21 (see FIG. 1). Also, the inner diameter D2 of the resolver rotor 1 is larger than the outer diameter D4 of the fixing portion 20 (see FIG. 3) described later. Further, the outer diameter D3 of the resolver rotor 1 is larger than the outer diameter D1 of the positioning portion 21. Therefore, the resolver rotor 1 is inserted into the motor rotor 2 from the X1 direction side, and the position in the X direction is determined by the positioning portion 21.

[0038] Also, the resolver rotor 1 has a protruding portion 10 that protrudes inward in the radial direction. The protruding portion 10 protrudes radially inward from the inner peripheral surface 1c of the resolver rotor 1.

[0039] Further, the resolver rotor 1 has a first thickness portion 11 and a second thickness portion 12 having a larger radial thickness than the first thickness portion 11. In the present embodiment, the resolver rotor 1 has a plurality of first thickness portions 11 and a plurality of second thickness portions 12. The plurality of first thickness portions 11 are provided at predetermined intervals in the circumferential direction. Also, the plurality of second thickness portions 12 are provided at predetermined intervals in the circumferential direction. Further, the plurality of first thickness portions 11 and the plurality of second thickness portions 12 are provided alternately. In the example shown in FIG. 2, the resolver rotor 1 has four first thickness portions 11 and four second thickness portions 12. That is, the resolver rotor 1 shown in FIG. 2 is a four-fold angle resolver rotor. The four first thickness portions 11 are arranged at intervals of 90 degrees. Also, the four second thickness portions 12 are arranged at intervals of 90 degrees.

[0040] (Groove portion of motor rotor) FIG. 3 is a schematic view of the fixed portion 20 of the motor rotor 2 as viewed from the X direction. As shown in FIG. 3, the fixed portion 20 has a groove portion 20a into which the protruding portion 10 (see FIG. 2) is engaged. Further, the outer diameter D4 of the fixed portion 20 is smaller than the inner diameter D2 (see FIG. 2) of the resolver rotor 1 (see FIG. 2). Further, the example shown in FIG. 3 is a schematic view of the fixed portion 20 as viewed from the X1 direction, and the second end face 20b which is the end face on the X1 direction side of the fixed portion 20 is shown. Further, in the example shown in FIG. 3, for convenience, the motor rotor 2 on the X1 direction side of the fixed portion 20 is illustrated by a broken line.

[0041] As shown in FIG. 4, the protruding portion 10 is provided to restrict the circumferential movement (rotation) of the resolver rotor 1 by being engaged with the groove portion 20a of the fixed portion 20.

[0042] Here, the resolver rotor 1 measures the rotation angle and / or the number of rotations of the motor rotor 2 (motor) by rotating integrally with the motor rotor 2 (see FIG. 3). Therefore, when the resolver rotor 1 and the motor rotor 2 rotate along the axis 90, if the resolver rotor 1 and the motor rotor 2 move relative to each other, the measurement accuracy of the rotation angle and / or the number of rotations decreases. Therefore, when fixing the resolver rotor 1 to the motor rotor 2, it is necessary to fix the resolver rotor 1 to the motor rotor 2 so that the resolver rotor 1 and the motor rotor 2 do not move relative to each other.

[0043] As a method of fixing the resolver rotor 1 to the motor rotor 2, a method of press-fitting a ring from the X1 direction side after inserting the resolver rotor 1 into the motor rotor 2, a method of fixing by caulking the resolver rotor 1 to the motor rotor 2, etc. can be considered. When the resolver rotor 1 is fixed by press-fitting a ring, the number of parts increases. Therefore, in the fixing structure 100 (see FIG. 1) of the resolver rotor 1 according to the present embodiment, the resolver rotor 1 is fixed to the motor rotor 2 by caulking the resolver rotor 1 to the motor rotor 2.

[0044] (Position where load is applied when caulking the motor rotor) In this embodiment, in a state where the protruding portion 10 is engaged with the groove portion 20a, the fixing portion 20 is caulked from the X1 direction to a portion 20c near the groove portion 20a on the second end face 20b on the X1 direction side, which is one axial side of the resolver rotor 1 with respect to the motor rotor 2, of the fixing portion 20. In this embodiment, the portion 20d other than the vicinity of the groove portion 20a on the second end face 20b is also caulked from the X1 direction.

[0045] Here, the resolver detects the rotation angle and / or the rotation speed of the motor rotor 2 that rotates together with the resolver rotor 1 based on the change in reactance between the resolver rotor 1 and the resolver stator provided outside the resolver rotor 1. Further, in order to improve the detection accuracy of the rotation angle and / or the rotation speed, the resolver is provided with a first thick portion 11 and a second thick portion 12 having different wall thicknesses from each other in the radial direction. When the first thick portion 11 and the second thick portion 12 are provided on the resolver rotor 1, if the difference in wall thickness between the first thick portion 11 and the second thick portion 12 in the radial direction becomes small, it approaches the shape of the resolver rotor in which no thick portions with different wall thicknesses are provided, so the detection accuracy of the rotation angle and / or the rotation speed decreases.

[0046] Therefore, in this embodiment, the resolver rotor 1 is caulked by applying a load to a portion of the second end face 20b of the fixing portion 20 corresponding to the second thick portion 12 of the resolver rotor 1. Specifically, the fixing portion 20 is caulked by applying loads to five locations 40a to 40e shown in FIG. 4. Note that the points where the loads are applied can be changed according to the shape of the resolver rotor 1.

[0047] FIG. 5 is a schematic diagram showing the fixing portion 20, the resolver rotor 1, and the positioning portion 21 in a state where the resolver rotor 1 is inserted into the motor rotor 2. In the example shown in FIG. 5, for convenience, the illustration of the portion of the motor rotor 2 on the X1 direction side of the fixing portion 20 is omitted.

[0048] As shown in Fig. 5, the portion 20c near the groove portion 20a on the X1 direction side of the second end face 20b and the portion 20d other than the vicinity of the groove portion 20a on the X1 direction side of the second end face 20b are equal in position in the axial direction. That is, the portion 20c near the groove portion 20a on the X1 direction side of the second end face 20b and the portion 20d other than the vicinity of the groove portion 20a on the X1 direction side of the second end face 20b are provided on the same plane.

[0049] (Punch member) Next, with reference to Fig. 6, the punch member 3 used when applying a load to the fixing portion 20 (see Fig. 4) will be described. The punch member 3 includes a first punch portion 30 and a second punch portion 31. The first punch portion 30 is configured to abut against the fixing portion 20 when applying a load to the portion 20c (see Fig. 4) near the groove portion 20a (see Fig. 3) of the fixing portion 20. Further, the second punch portion 31 is configured to abut against the fixing portion 20 when applying a load to the portion 20d (see Fig. 4) other than the vicinity of the groove portion 20a.

[0050] In the present embodiment, the first punch portion 30 has two abutting portions 30a and 30b. The abutting portions 30a and 30b are portions that abut against the portion 20c near the groove portion 20a of the second end face 20b (see Fig. 3). Specifically, the two abutting portions 30a and 30b abut against the points 40a and 40b shown in Fig. 4.

[0051] Further, the second punch portion 31 has one abutting portion 31a. The abutting portion 31a is a portion that abuts against the portion 20d other than the vicinity of the groove portion 20a of the second end face 20b. In the present embodiment, in order to caulk three locations other than the vicinity of the groove portion 20a of the fixing portion 20, the punch member 3 includes three second punch portions 31. The abutting portions 31a of the three second punch portions 31 abut against the points 40c to 40e shown in Fig. 4, respectively.

[0052] In this embodiment, the fixing portion 20 includes a first caulking portion 41 (see FIG. 8) formed by applying a load to portions 20c (points 40a and 40b) near the groove portion 20a, and a second caulking portion 43 (see FIG. 12) formed by applying a load to portions 20d (points 40c to 40e) other than the vicinity of the groove portion 20a. That is, the first caulking portion 41 and the second caulking portion 43 are provided at portions corresponding to the second thick portion 12 (see FIG. 4) of the resolver rotor 1.

[0053] (First caulking portion) Next, with reference to FIGS. 7 to 10, the first caulking portion 41 (see FIG. 8) formed in the vicinity of the groove portion 20a (see FIG. 7) of the fixing portion 20 (see FIG. 7) will be described.

[0054] FIG. 7 shows a state in which the first punch portion 30 is brought into contact with the second end face 20b of the fixing portion 20 in order to form the first caulking portion 41 by the punch member 3. Specifically, in the example shown in FIG. 7, the contact portions 30a and 30b are brought into contact with both sides of the groove portion 20a. In this embodiment, in the state shown in FIG. 7, by applying a load from the X1 direction side toward the X2 direction side, the first caulking portion 41 is formed as shown in FIG. 8.

[0055] As shown in FIG. 8, a first caulking portion 41a is formed on the portion 22a on the Y1 direction side in the vicinity of the groove portion 20a of the second end face 20b by the contact portion 30a of the first punch portion 30. Also, a first caulking portion 41b is formed on the portion 22b on the Y2 direction side in the vicinity of the groove portion 20a of the second end face 20b by the contact portion 30b of the first punch portion 30.

[0056] Note that the width W1 in the Y direction of the contact portion 30a and the width W2 in the Y direction of the contact portion 30b are equal to each other. Therefore, the width W3 in the Y direction of the first caulking portion 41a and the width W4 in the Y direction of the first caulking portion 41b are also equal to each other.

[0057] The example shown in FIG. 9 is an enlarged view of a portion of the fixing portion 20 where the first caulking portion 41a and the first caulking portion 41b are formed. In the present embodiment, the first caulking portion 41a is formed at a predetermined interval from the inner surface 23 of the groove portion 20a in the Y1 direction. Therefore, an edge portion 20e is formed between the first caulking portion 41a and the groove portion 20a. Further, the second caulking portion 41b is formed at a predetermined interval from the inner surface 23 of the groove portion 20a in the Y2 direction. Therefore, an edge portion 20f is formed between the second caulking portion 41b and the groove portion 20a.

[0058] The example shown in FIG. 10 is a cross-sectional view taken along the line I-I in FIG. 9. As shown in FIG. 10, the first caulking portion 41 is configured to fix the resolver rotor 1 (see FIG. 1) from the X1 direction by being deformed so that the distance D5 between the inner surfaces 23 on the second end surface 20b side of the groove portion 20a becomes small. That is, the first caulking portion 41 is deformed so that the distance D5 between the inner surfaces 23 on the second end surface 20b side of the groove portion 20a is smaller than the distance D6 between the inner surfaces 23 on the side opposite to the second end surface 20b of the groove portion 20a. The distance between the inner surfaces 23 of the groove portion 20a is the distance between the inner surface 23a on the Y1 direction side and the inner surface 23b on the Y2 direction side of the groove portion 20a.

[0059] In the present embodiment, the first caulking portion 41 includes a first deformed portion 42 that is deformed inward of the groove portion 20a in the circumferential direction. The first deformed portion 42 is a portion where the inner surface 23 of the groove portion 20a is deformed into a drum-shaped cross-sectional shape that bulges inward of the groove portion 20a.

[0060] In the present embodiment, as shown by the circle 42a illustrated by a broken line, the first deformed portion 42 abuts on the first end surface 1a from the X1 direction side by being deformed inward of the groove portion 20a in the circumferential direction.

[0061] Also, in the present embodiment, as shown by the circle 42b illustrated by a broken line, the first deformed portion 42 is provided so as to fix the resolver rotor 1 in a state of being in contact with the side surfaces 10a and 10b of the protruding portion 10 from both sides in the circumferential direction. In the present embodiment, the first deformed portion 42 is provided on both the first caulking portions 41a and 41b. Therefore, the first caulking portion 41 restricts the movement of the protruding portion 10 of the resolver rotor 1 in the circumferential direction and the axial direction by the first deformed portions 42 formed on both sides in the circumferential direction of the groove portion 20a.

[0062] Note that the first deformed portion 42 is formed by deforming the portion on the X1 direction side among the portions 22a and 22b on both sides in the circumferential direction of the groove portion 20a. Therefore, the first deformed portion 42 of the first caulking portion 41a is in contact with the side surface 10a on the X1 direction side of the protruding portion 10 of the resolver rotor 1 on the X1 direction side, but is not in contact with the side surface 10a on the X1 direction side of the resolver rotor 1 on the X2 direction side. That is, on the X2 direction side, as shown by the circle 50a illustrated by a broken line, a gap is formed between the first deformed portion 42 and the side surface 10a on the X1 direction side of the resolver rotor 1.

[0063] Also, the first deformed portion 42 of the first caulking portion 41b is in contact with the side surface 10b on the X2 direction side of the protruding portion 10 of the resolver rotor 1 on the X1 direction side, but is not in contact with the side surface 10b on the X2 direction side of the resolver rotor 1 on the X2 direction side. That is, on the X2 direction side, as shown by the circle 50b illustrated by a broken line, a gap is formed between the first deformed portion 42 and the side surface 10b on the X2 direction side of the resolver rotor 1.

[0064] That is, the first caulking portion 41 according to the present embodiment can restrict the movement of the protruding portion 10 of the resolver rotor 1 in the circumferential direction and the axial direction while minimizing the deformation of the protruding portion 10 of the resolver rotor 1.

[0065] (Second caulking portion) Next, with reference to FIGS. 11 to 13, the second caulking portion 43 (see FIG. 12) formed in the portion 20d (see FIG. 4) other than the vicinity of the groove portion 20a (see FIG. 7) of the fixing portion 20 (see FIG. 11) will be described.

[0066] Figure 11 shows a state in which the second punching portion 31 is brought into contact with the second end face 20b of the fixing portion 20 in order to form the second caulking portion 43 by the punching member 3. In the present embodiment, in the state shown in Figure 11, by applying a load from the X1 direction side toward the X2 direction side, as shown in Figure 12, the second caulking portion 43 is formed.

[0067] As shown in Figure 12, the second caulking portion 43 is formed by the second punching portion 31 on the portion 20d (see Figure 4) of the second end face 20b other than the vicinity of the groove portion 20a (see Figure 4). In the present embodiment, as shown in Figure 4, the portion 20d other than the vicinity of the groove portion 20a is a portion spaced a predetermined distance in the circumferential direction from the portion 20c (see Figure 4) in the vicinity of the groove portion 20a. Therefore, the second caulking portion 43 is formed by caulking the portion 20d other than the vicinity of the groove portion 20a, which is spaced a predetermined circumferential distance from the portion 20c in the vicinity of the groove portion 20a, of the second end face 20b, and fixing the resolver rotor 1 (see Figure 4) from the X1 direction side together with the first caulking portion 41.

[0068] Note that the width W5 in the Y direction of the contact portion 31a is equal to the width W1 in the Y direction of the contact portion 30a of the first punching portion 30 shown in Figure 8 and the width W2 in the Y direction of the contact portion 30b. Therefore, the width W6 in the Y direction of the second caulking portion 43 is equal to the width W3 in the Y direction of the first caulking portion 41a and the width W4 in the Y direction of the first caulking portion 41b shown in Figure 8.

[0069] The example shown in Figure 13 is an enlarged view of the portion where the second caulking portion 43 is formed. In the present embodiment, the second caulking portion 43 is formed on the outer peripheral side of the second end face 20b of the fixing portion 20. Specifically, the second caulking portion 43 is formed by deforming the outer surface 20g of the second end face 20b.

[0070] The example shown in Fig. 14 is a cross-sectional view taken along line II-II in Fig. 13. As shown in Fig. 14, the second caulking portion 43 includes a second deformed portion 44 that deforms outward in the radial direction. The second deformed portion 44 is a portion where the outer surface 20g of the second end face 20b is deformed into an arcuate cross-sectional shape. In the present embodiment, as shown by a circle 44a illustrated by a broken line, the second deformed portion 44 abuts on the first end face 1a of the resolver rotor 1 from the X1 direction side. Further, in the present embodiment, as shown by a circle 44b illustrated by a broken line, the second deformed portion 44 is provided so as to fix the resolver rotor 1 in a state of abutting on the inner peripheral surface 1c of the resolver rotor 1 from the inner side in the radial direction.

[0071] Note that the second deformed portion 44 is formed by deforming a portion on the X1 direction side of the second end face 20b other than the vicinity of the groove portion 20a of the groove portion 20a. Therefore, the second deformed portion 44 of the second caulking portion 43 abuts on the inner peripheral surface 1c of the resolver rotor 1 on the X1 direction side, but does not abut on the inner peripheral surface 1c of the resolver rotor 1 on the X2 direction side. That is, on the X2 direction side, as shown by a circle 51 illustrated by a broken line, a gap is formed between the second deformed portion 44 and the inner peripheral surface 1c of the resolver rotor 1.

[0072] (Method for fixing resolver rotor) Next, with reference to Fig. 15, a method for fixing the resolver rotor 1 (see Fig. 1) according to the present embodiment will be described.

[0073] In step S100, a step of engaging a protruding portion 10 (see Fig. 2) of the resolver rotor 1 that protrudes inward in the radial direction with respect to a groove portion 20a (see Fig. 3) of a fixing portion 20 (see Fig. 1) provided on the motor rotor 2 (see Fig. 1) and to which the resolver rotor 1 is fixed is performed.

[0074] Next, in step S101, with the protruding portion 10 engaged with the groove portion 20a, a load is applied in the X1 direction to a portion 20c (see FIG. 4) near the groove portion 20a on the second end face 20b (see FIG. 3) of the resolver rotor 1 on the X1 direction side, which is one axial side of the motor rotor 2, of the fixing portion 20, closer to the X1 direction than the first end face 1a (see FIG. 1) of the resolver rotor 1. Then, the groove portion 20a is deformed so that the distance D5 (see FIG. 10) between the inner side surfaces 23 (see FIG. 10) on the second end face 20b side of the groove portion 20a becomes smaller, thereby caulking the resolver rotor 1. After that, the method for fixing the resolver rotor 1 ends.

[0075] Note that in the present embodiment, in the step of caulking the resolver rotor 1 performed in step S101, as shown in FIG. 4, by applying a load to a portion 20c near the groove portion 20a and a portion 20d other than the vicinity of the groove portion 20a on the second end face 20b, the resolver rotor 1 is caulked simultaneously at predetermined intervals in the circumferential direction. Also, in the present embodiment, in the step of caulking the resolver rotor 1 performed in step S101, as shown in FIG. 4, by applying a load to a portion of the second end face 20b corresponding to the second thick portion 12 of the resolver rotor 1, the resolver rotor 1 is caulked.

[0076] Also, in the present embodiment, in the step of caulking the resolver rotor 1 performed in step S101, as shown in FIG. 8, a load is applied to portions on both sides of the groove portion 20a on the second end face 20b by a punch member 3 having two abutting portions 30a and 30b.

[0077] Also, in the present embodiment, in the step of caulking the resolver rotor 1 performed in step S101, as shown in FIG. 9, a load is applied to portions 22a and 22b on both sides in the circumferential direction of the groove portion 20a near the groove portion 20a with which the protruding portion 10 is engaged on the second end face 20b, thereby caulking the resolver rotor 1.

[0078] (Effect of the method for fixing the resolver rotor according to the present embodiment) In the method for fixing the resolver rotor 1 according to this embodiment, the following effects can be obtained.

[0079] In this embodiment, the method for fixing the resolver rotor 1 is a method for fixing the resolver rotor 1 to the motor rotor 2. The method includes engaging a protruding portion 10 of the resolver rotor 1 that protrudes radially inward with respect to a groove portion 20a of a fixing portion 20 provided on the motor rotor 2 and to which the resolver rotor 1 is fixed, and applying a load from the X1 direction to a portion 20c near the groove portion 20a on a second end face 20b on the X1 direction side, which is one axial side of the motor rotor 2, of the fixing portion 20 in a state where the protruding portion 10 is engaged with the groove portion 20a, thereby deforming the groove portion 20a so that the distance D5 between inner surfaces 23 on the second end face 20b side of the groove portion 20a becomes smaller, and caulking the resolver rotor 1. As a result, the inner surfaces 23 on the second end face 20b side of the groove portion 20a can be brought into contact with both side surfaces of the protruding portion 10, and the inner surfaces 23 on the second end face 20b side of the groove portion 20a can be brought into contact with the first end face 1a of the resolver rotor 1 from the X1 direction side. Therefore, the movement (rotation) of the resolver rotor 1 in the circumferential direction can be restricted by the inner surfaces 23 on the second end face 20b side of the groove portion 20a, and the movement of the resolver rotor 1 from the X1 direction side can be restricted. As a result, compared with a configuration in which the movement of the resolver rotor 1 is restricted by contacting only both sides in the circumferential direction with respect to the protruding portion 10 of the resolver rotor 1, the axial pull-out load of the resolver rotor 1 can be increased.

[0080] Also, in this embodiment, in the process of caulking the resolver rotor 1, by applying a load to a portion 20c near the groove portion 20a and a portion 20d other than the vicinity of the groove portion 20a on the second end face 20b, the resolver rotor 1 is caulked simultaneously at predetermined intervals in the circumferential direction. As a result, the portion 20c near the groove portion 20a and the portion 20d other than the vicinity of the groove portion 20a on the second end face 20b can be caulked in a single caulking process. Therefore, compared with a configuration in which the portion 20c near the groove portion 20a and the portion 20d other than the vicinity of the groove portion 20a are caulked by different processes, the number of working steps can be reduced. As a result, productivity can be improved.

[0081] Also, in this embodiment, in the process of caulking the resolver rotor 1, by applying a load to both sides 22a and 22b of the circumferential groove portion 20a in the vicinity of the groove portion 20a with which the protrusion 10 on the second end face 20b is engaged, the resolver rotor 1 is caulked. As a result, by deforming both sides 22a and 22b of the circumferential groove portion 20a on the second end face 20b by the load, both sides 22a and 22b of the circumferential groove portion 20a on the second end face 20b can be brought into contact with the protrusion 10 of the resolver rotor 1 from the X1 direction side. Therefore, the movement of the resolver rotor 1 in the axial direction can be restricted by both sides 22a and 22b on the circumferential sides of the second end face 20b. As a result, compared with a configuration in which a load is applied only to one side portion of the circumferential groove portion 20a on the second end face 20b, the pull-out load of the resolver rotor 1 can be made even larger.

[0082] Further, in the present embodiment, the resolver rotor 1 has a first thickness portion 11 and a second thickness portion 12 whose thickness in the radial direction is larger than that of the first thickness portion 11. In the process of caulking the resolver rotor 1, the resolver rotor 1 is caulked by applying a load to a portion of the second end face 20b corresponding to the second thickness portion 12 of the resolver rotor 1. Thereby, even when the resolver rotor 1 is deformed as the fixing portion 20 is deformed, the resolver rotor 1 can be deformed so that the difference in thickness in the radial direction between the first thickness portion 11 and the second thickness portion 12 becomes large. As a result, when the resolver rotor 1 having the first thickness portion 11 and the second thickness portion 12 is fixed to the motor rotor 2, it is possible to suppress a decrease in the detection accuracy of the rotation angle and / or the rotation speed.

[0083] Further, in the present embodiment, a portion 20c near the groove portion 20a on the X1 direction side of the second end face 20b and a portion 20d other than the vicinity of the groove portion 20a on the X1 direction side of the second end face 20b are equal in position in the axial direction. Thereby, since the positions of the portion 20c near the groove portion 20a and the portion 20d other than the vicinity of the groove portion 20a of the second end face 20b are equal to each other in the axial direction, when a load is applied simultaneously from the X1 direction side to the portion 20c near the groove portion 20a and the portion 20d other than the vicinity of the groove portion 20a of the second end face 20b, loads of equal magnitude can be easily applied to both the portion 20c near the groove portion 20a and the portion 20d other than the vicinity of the groove portion 20a.

[0084] Further, in the present embodiment, in the process of caulking the resolver rotor 1, a load is applied to portions 22a and 22b on both sides of the groove portion 20a of the second end face 20b by a punch member 3 having two abutting portions 30a and 30b. Thereby, loads can be applied to each of the portions 22a and 22b on both sides of the circumferential groove portion 20a by the two abutting portions 30a and 30b. As a result, the positions on both sides of the circumferential groove portion 20a can be easily caulked.

[0085] (Effect of the Resolver Rotor Fixing Structure According to the Present Embodiment) In the fixing structure 100 of the resolver rotor 1 according to this embodiment, the following effects can be obtained.

[0086] In this embodiment, the fixing structure 100 of the resolver rotor 1 includes a motor rotor 2 and a resolver rotor 1 fixed to the motor rotor 2 on the outer side in the radial direction of the motor rotor 2. The resolver rotor 1 has a protruding portion 10 protruding inward in the radial direction, and the motor rotor 2 has a fixing portion 20 to which the resolver rotor 1 is fixed. The fixing portion 20 has a groove portion 20a into which the protruding portion 10 is engaged. In a state where the protruding portion 10 is engaged with the groove portion 20a, the fixing portion 20 is caulked from the X1 direction with respect to a portion 20c near the groove portion 20a on the second end face 20b on the X1 direction side, which is one side in the axial direction of the motor rotor 2, of the resolver rotor 1 among the fixing portions 20. As a result, the distance D5 between the inner surfaces 23 on the second end face 20b side of the groove portion 20a is deformed to be reduced, and the fixing structure 100 includes a first caulking portion 41 for fixing the resolver rotor 1 from the X1 direction. Thereby, similar to the fixing method of the resolver rotor 1 according to this embodiment, a fixing structure 100 of the resolver rotor 1 capable of increasing the axial pull-out load of the resolver rotor 1 can be provided.

[0087] Further, in this embodiment, the first caulking portion 41 includes a first deformed portion 42 deformed inward in the circumferential direction of the groove portion 20a. The first deformed portion 42 is deformed inward in the circumferential direction of the groove portion 20a so as to abut against the first end face 1a from the X1 direction side and to fix the resolver rotor 1 in a state of abutting against the side faces 10a and 10b of the protruding portion 10 from both sides in the circumferential direction. Thereby, since the first deformed portion 42 abuts against the first end face 1a from the X1 direction side and abuts against the side faces 10a and 10b of the protruding portion 10 from both sides in the circumferential direction, the axial movement and circumferential movement (rotation) of the resolver rotor 1 can be easily restricted.

[0088] In addition, in the present embodiment, the fixing portion 20 further includes a second caulking portion 43 that fixes the resolver rotor 1 from the X1 direction side together with the first caulking portion 41 by caulking a portion 20d other than the vicinity of the groove portion 20a, which is at a predetermined interval in the circumferential direction from the portion 20c near the groove portion 20a, of the second end face 20b. Thereby, the first caulking portion 41 and the second caulking portion 43 can be formed simultaneously. Therefore, compared with a lattice in which the first caulking portion 41 and the second caulking portion 43 are formed separately, the number of working steps can be reduced. As a result, it is possible to provide a fixing structure 100 for the resolver rotor 1 that can improve productivity.

[0089] In addition, in the present embodiment, the resolver rotor 1 has a first thickness portion 11 and a second thickness portion 12 whose thickness in the radial direction is larger than that of the first thickness portion 11, and the first caulking portion 41 and the second caulking portion 43 are provided at portions corresponding to the second thickness portion 12 of the resolver rotor 1. Thereby, even when the resolver rotor 1 is deformed when the first caulking portion 41 and the second caulking portion 43 are formed, the resolver rotor 1 can be deformed in a direction in which the thickness in the radial direction of the first thickness portion 11 and the second thickness portion 12 increases. As a result, even when the resolver rotor 1 is fixed by the first caulking portion 41 and the second caulking portion 43, it is possible to suppress a decrease in the detection accuracy of the rotation angle and / or the rotation speed.

[0090] In addition, in the present embodiment, the second caulking portion 43 includes a second deformation portion 44 that deforms outward in the radial direction, and the second deformation portion 44 is provided so as to fix the resolver rotor 1 in a state of abutting against the first end face 1a of the resolver rotor 1 from the X1 direction side and abutting against the inner peripheral surface 1c of the resolver rotor 1 from the inner side in the radial direction. Thereby, while increasing the size of the second deformation portion 44 in the radial direction, it is possible to make it abut against the first end face 1a from the X1 direction side. As a result, the second deformation portion 44 can function as a retaining portion for the resolver rotor 1.

[0091] [Modification Example] It should be noted that the embodiments disclosed this time should be considered as illustrative in all respects and not restrictive. The scope of the present invention is shown not by the description of the above embodiments but by the claims, and further includes all changes (modifications) within the meaning and scope equivalent to the claims.

[0092] For example, in the above embodiment, an example of a configuration in which a load is applied to a portion 20c near the groove portion 20a of the second end face 20b of the fixing portion 20 by the punch member 3 having two abutting portions 30a and 30b was shown, but the present invention is not limited to this. For example, a load may be applied to a portion 20c near the groove portion 20a of the second end face 20b of the fixing portion 20 by the punch member 103 according to the first modification example shown in FIG. 16.

[0093] As shown in FIG. 16, the punch member 103 according to the first modification example has a punch portion 32. Further, the punch member 103 has a single abutting portion 32a. The width W7 in the Y direction of the abutting portion 32a is larger than the distance D6 between the inner surfaces 23 of the groove portion 20a. That is, the abutting portion 32a abuts on both the portion 22a on the Y1 direction side and the portion 22b on the Y2 direction side of the groove portion 20a. Thereby, the abutting portion 32a forms caulked portions 45 on both the portion 22a on the Y1 direction side and the portion 22b on the Y2 direction side of the groove portion 20a. Note that when the caulked portions 45 are formed by the punch member 103 according to the first modification example as shown in FIG. 16, no edge portions are formed on the Y2 direction side of the portion 22a on the Y1 direction side of the groove portion 20a and on the Y1 direction side of the portion 22b on the Y2 direction side of the groove portion 20a.

[0094] Next, with reference to FIG. 17, a method of fixing the resolver rotor 1 (see FIG. 1) by the punch member 103 (see FIG. 16) according to the first modification example will be described. Note that the same steps as those for the method of fixing the resolver rotor 1 using the punch member 3 (see FIG. 6) according to the above embodiment are denoted by the same reference numerals, and detailed description thereof will be omitted.

[0095] In step S100, a step of engaging the protruding portion 10 (see FIG. 2) with the groove portion 20a (see FIG. 16) is performed.

[0096] Next, in step S102, a step of caulking the resolver rotor 1 is performed. In the first modification, in the step of caulking the resolver rotor 1, as shown in FIG. 16, a load is applied to the portions 22a and 22b on both sides of the groove portion 20a of the second end face 20b by a punch member 103 having a single contact portion 32a. Thereafter, the method of fixing the resolver rotor 1 ends.

[0097] In the first modification, as described above, in the step of caulking the resolver rotor 1, a load is applied to the portions 22a and 22b on both sides of the groove portion 20a of the second end face 20b by a punch member 103 having a single contact portion 32a. As a result, the single contact portion 32a can deform the portions 22a and 22b on both sides of the groove portion 20a of the second end face 20b. As a result, a load can be applied to the portion 20c near the groove portion 20a and the portion 20d other than the vicinity of the groove portion 20a without changing the shape of the contact portion between the portion 20c near the groove portion 20a and the portion 20d other than the vicinity of the groove portion 20a, so that the shape of the punch member 103 can be prevented from becoming complicated.

[0098] Also, in the above embodiment, an example of a configuration in which the resolver rotor 1 is a so-called four-fold angle resolver rotor having four first thickness portions 11 and four second thickness portions 12 is shown, but the present invention is not limited to this. For example, like the resolver rotor 101 of the second modification shown in FIG. 18, a so-called two-fold angle resolver rotor having two first thickness portions 111 and two second thickness portions 112 may be used. Also in the second modification, in the step of caulking the resolver rotor 101, the resolver rotor 101 is caulked by applying a load to the portion (points 40a to 40c) corresponding to the second thickness portion 112 of the resolver rotor 101.

[0099] In the above-described embodiment, an example of the configuration in which the resolver rotor 1 has four first-thickness portions 11 and four second-thickness portions 12, i.e., a so-called four-fold angle resolver rotor, has been shown. However, the present invention is not limited to this. For example, like the resolver rotor 201 of the third modification shown in FIG. 19, it may be a so-called three-fold angle resolver rotor having three first-thickness portions 211 and three second-thickness portions 212. Also in the third modification, in the process of caulking the resolver rotor 201, the resolver rotor 201 is caulked by applying a load to the portions (points 40a to 40d) corresponding to the second-thickness portions 212 of the resolver rotor 201.

[0100] In the above-described embodiment, in the process of caulking the resolver rotor 1, an example of the configuration in which the resolver rotor 1 is simultaneously caulked by applying loads to the portion 20c near the groove portion 20a and the portion 20d other than the vicinity of the groove portion 20a on the second end face 20b has been shown. However, the present invention is not limited to this. In the process of caulking the portion 20c near the groove portion 20a, it is not necessary to simultaneously caulk the portion 20d other than the vicinity of the groove portion 20a. However, when the portion 20c near the groove portion 20a and the portion 20d other than the vicinity of the groove portion 20a are not simultaneously caulked in the process of caulking the resolver rotor 1, the number of working steps required for fixing the resolver rotor 1 increases, and the productivity decreases. Therefore, in the process of caulking the resolver rotor 1, it is preferable to simultaneously caulk the resolver rotor 1 by applying loads to the portion 20c near the groove portion 20a and the portion 20d other than the vicinity of the groove portion 20a on the second end face 20b.

[0101] In the above-described embodiment, in the process of caulking the resolver rotor 1, an example of the configuration in which the resolver rotor 1 is simultaneously caulked at predetermined intervals in the circumferential direction has been shown. However, the present invention is not limited to this. For example, in the process of caulking the resolver rotor 1, the resolver rotor 1 may be caulked at a position facing the portion 20c near the groove portion 20a and the portion 20c near the groove portion 20a. As long as it is possible to stably fix the resolver rotor 1 to the motor rotor 2, the caulking position of the resolver rotor 1 does not matter.

[0102] Further, in the above-described embodiment, an example of a configuration in which the width W1 in the Y direction of the contact portion 30a of the first punch portion 30, the width W2 in the Y direction of the contact portion 30b, and the width W5 in the Y direction of the contact portion 31a of the second punch portion 31 are equal to each other has been shown. However, the present invention is not limited to this. Each of the width W1 in the Y direction of the contact portion 30a, the width W2 in the Y direction of the contact portion 30b, and the width W5 in the Y direction of the contact portion 31a may have different sizes from each other.

[0103] Also, in the above-described embodiment, an example of a configuration in which the resolver rotor 1 is caulked by applying a load to the portions 22a and 22b on both sides of the groove portion 20a in the process of caulking the resolver rotor 1 has been shown. However, the present invention is not limited to this. As long as the resolver rotor 1 can be stably fixed, the resolver rotor 1 may be caulked by applying a load to either one of the portions 22a and 22b on both sides of the groove portion 20a.

[0104] Further, in the above-described embodiment, an example of a configuration in which the resolver rotor 1 is caulked by applying a load to the portion of the second end face 20b corresponding to the second thick portion 12 in the process of caulking the resolver rotor 1 has been shown. However, the present invention is not limited to this. For example, the resolver rotor 1 may be caulked by applying a load to the portion of the second end face 20b corresponding to the first thick portion 11. However, when the resolver rotor 1 is caulked by applying a load to the portion corresponding to the first thick portion 11, the measurement accuracy of the rotation angle and / or the rotation speed by the resolver rotor 1 decreases. Therefore, in the process of caulking the resolver rotor 1, it is preferable to caulk the resolver rotor 1 by applying a load to the portion of the second end face 20b corresponding to the second thick portion 12.

[0105] Further, in the above-described embodiment, an example of the configuration in which the first caulking portion 41 and the second caulking portion 43 are provided at positions corresponding to the second thick portion 12 of the resolver rotor 1 has been shown, but the present invention is not limited to this. For example, the first caulking portion 41 and the second caulking portion 43 may be provided at positions corresponding to the first thick portion 11 of the resolver rotor 1. However, when the first caulking portion 41 and the second caulking portion 43 are provided at positions corresponding to the first thick portion 11 of the resolver rotor 1, the measurement accuracy of the rotation angle and / or the rotation speed by the resolver rotor 1 decreases. Therefore, it is preferable that the first caulking portion 41 and the second caulking portion 43 are provided at positions corresponding to the second thick portion 12 of the resolver rotor 1.

[0106] Further, in the above-described embodiment, an example of the configuration in which the fixing portion 20 includes both the first caulking portion 41 and the second caulking portion 43 has been shown, but the present invention is not limited to this. For example, the fixing portion 20 may include at least the first caulking portion 41 and not include the second caulking portion 43. However, when the fixing portion 20 does not include the second caulking portion 43, it becomes difficult to stably fix the resolver rotor 1. Therefore, it is preferable that the fixing portion 20 includes both the first caulking portion 41 and the second caulking portion 43.

[0107] Further, in the above-described embodiment, an example of the configuration in which an edge portion 20e is formed between the first caulking portion 41a and the groove portion 20a and an edge portion 20f is formed between the first caulking portion 41b and the groove portion 20a has been shown, but the present invention is not limited to this. For example, the first caulking portion 41a and the first caulking portion 41b may be formed at positions where the edge portion 20e and the edge portion 20f are not formed.

Explanation of reference numerals

[0108] 1,101,201... resolver rotor, 1a... first end face (end face of the resolver rotor on the first direction side), 1c... inner peripheral surface (inner peripheral surface of the resolver rotor), 2... motor rotor, 3... punch member, 10... protrusion, 10a... side surface (side surface of the protrusion), 11, 111, 211... first thickness portion, 12, 112, 212... second thickness portion, 20... fixing portion, 20a... groove portion, 22a, 22b... portions on both sides of the circumferential groove portion, 23... inner surface (inner surface of the groove portion), 30a, 30b... two abutting portions, 32a... single abutting portion, 41, 41a, 41b... first caulking portion, 42... first deformed portion, 43... second caulking portion, 44... second deformed portion, 100... fixing structure of the resolver rotor, X1 direction... first direction

Claims

1. A method for fixing a resolver rotor to a motor rotor, comprising: engaging a protruding portion of the resolver rotor that protrudes inward in the radial direction with a groove portion of a fixing portion provided on the motor rotor and to which the resolver rotor is fixed; deforming the groove portion by applying a load from the first direction to a portion near the groove portion of a second end face on the first direction side, which is one axial side of the motor rotor, of the fixing portion in a state where the protruding portion is engaged with the groove portion, so that the distance between inner surfaces on the second end face side of the groove portion becomes smaller, thereby caulking the resolver rotor.

2. The method for fixing a resolver rotor according to claim 1, wherein in the step of caulking the resolver rotor, the resolver rotor is caulked simultaneously at predetermined intervals in the circumferential direction by applying the load to a portion near the groove portion and a portion other than the portion near the groove portion of the second end face.

3. The method for fixing a resolver rotor according to claim 2, wherein in the step of caulking the resolver rotor, the resolver rotor is caulked by applying the load to portions on both sides in the circumferential direction of the groove portion near which the protruding portion is engaged on the second end face.

4. The resolver rotor has a first thickness portion and a second thickness portion having a larger thickness in the radial direction than the first thickness portion. The method for fixing a resolver rotor according to claim 3, wherein in the step of caulking the resolver rotor, the resolver rotor is caulked by applying the load to a portion of the second end face corresponding to the second thickness portion of the resolver rotor.

5. A motor rotor and a resolver rotor fixed to the motor rotor on the outer side in the radial direction of the motor rotor, wherein the resolver rotor has a protruding portion that protrudes inward in the radial direction, the motor rotor has a fixing portion to which the resolver rotor is fixed, and the fixing portion has a groove portion into which the protruding portion is engaged. The fixing portion includes a first caulking portion that fixes the resolver rotor from the first direction. In a state where the protruding portion is engaged with the groove portion, the fixing portion is caulked from the first direction against a portion near the groove portion on a second end surface on the first direction side, which is one axial side of the motor rotor, of the fixing portion. As a result, the distance between the inner surfaces on the second end surface side of the groove portion is deformed to become smaller, and the resolver rotor is fixed from the first direction.

6. The first caulking portion includes a first deformed portion deformed toward the inside of the groove portion in the circumferential direction. The first deformed portion is provided to fix the resolver rotor in a state where it abuts against the first end surface from the first direction side and abuts against the side surfaces of the protruding portion from both sides in the circumferential direction by being deformed toward the inside of the groove portion in the circumferential direction. The fixing structure of the resolver rotor according to claim 5.

7. The fixing portion further includes a second caulking portion that fixes the resolver rotor from the first direction side together with the first caulking portion by caulking a portion other than the portion near the groove portion, which is provided at a predetermined interval in the circumferential direction from the portion near the groove portion, of the second end surface. The fixing structure of the resolver rotor according to claim 6.

8. The resolver rotor has a first thick portion and a second thick portion having a larger thickness in the radial direction than the first thick portion. The first caulking portion and the second caulking portion are provided at portions corresponding to the second thick portion of the resolver rotor. The fixing structure of the resolver rotor according to claim 7.

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