Resolver rotor

Abstract

To obtain a resolver rotor in which a first magnetic portion and a second magnetic portion can be provided on the outer peripheral surface of a non-magnetic body without increasing the size of a masking device that masks the outer peripheral surface of the non-magnetic body.SOLUTION: A resolver rotor 2 includes a non-magnetic body 201 formed in a ring shape, and a magnetic body 202 provided on an outer peripheral surface 203 of the non-magnetic body 201. The magnetic body 202 has a first magnetic portion 204 and a second magnetic portion 205 spaced apart from the first magnetic portion 204 in the axial direction D1. The outer peripheral surface 203 of the non-magnetic body 201 has a first outer peripheral surface 206 on which the first magnetic portion 204 is provided, a second outer peripheral surface 207 on which the second magnetic portion 205 is provided, and a first intermediate outer peripheral surface 208 provided between the first outer peripheral surface 206 and the second outer peripheral surface 207. The first intermediate outer peripheral surface 208 is disposed so as to be shifted from each of the first outer peripheral surface 206 and the second outer peripheral surface 207 in the radial direction D2.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] The present invention relates to a resolver rotor. [Background technology]

[0002] Conventionally, a resolver rotor is known that includes a non-magnetic body formed in a ring shape and a magnetic body provided on the outer circumferential surface of the non-magnetic body. The area per unit length of the magnetic body along the circumferential direction changes periodically in response to the change in the circumferential position. As a result, the gap permeance between the resolver stator and the resolver rotor changes periodically in response to the change in the circumferential position of the resolver rotor (for example, see Patent Document 1). [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2022-55676 A Summary of the Invention [Problem to be solved by the invention]

[0004] With areas of the outer peripheral surface of the non-magnetic body other than the area where the magnetic body is to be provided being masked, molten magnetic material powder is sprayed onto the outer peripheral surface of the non-magnetic body, thereby providing the magnetic body on the outer peripheral surface of the non-magnetic body.

[0005] A mask device for masking an outer peripheral surface of a non-magnetic body includes a first mask part and a second mask part. The first mask part and the second mask part sandwich the non-magnetic body in the axial direction, thereby masking the outer peripheral surface of the non-magnetic body.

[0006] By configuring the magnetic body to have a first magnetic portion and a second magnetic portion axially spaced from the first magnetic portion, a magnetic path passing through the first magnetic portion and a magnetic path passing through the second magnetic portion can be formed on the outer circumferential surface of the non-magnetic body. This allows the resolver stator to obtain two different signals corresponding to the gap permeance between the resolver stator and the resolver rotor. By using two different signals corresponding to the gap permeance between the resolver stator and the resolver rotor, the measurement accuracy of the resolver can be improved.

[0007] However, even if the first mask part and the second mask part sandwich the non-magnetic body in the axial direction, the area between the first magnetic part and the second magnetic part on the outer peripheral surface of the non-magnetic body cannot be masked. Therefore, the mask device for masking the outer peripheral surface of the non-magnetic body must be configured to further include a third mask part for masking the area between the first magnetic part and the second magnetic part on the outer peripheral surface of the non-magnetic body. This causes a problem that the mask device for masking the outer peripheral surface of the non-magnetic body becomes large.

[0008] The present invention has been made to solve the above-mentioned problems, and its purpose is to provide a resolver rotor in which a first magnetic portion and a second magnetic portion can be provided on the outer peripheral surface of a non-magnetic body without increasing the size of a masking device that masks the outer peripheral surface of the non-magnetic body. [Means for solving the problem]

[0009] The resolver rotor of the present invention comprises a non-magnetic body formed in a ring shape and a magnetic body provided on the outer peripheral surface of the non-magnetic body, the magnetic body having a first magnetic portion and a second magnetic portion spaced from the first magnetic portion in the axial direction of the non-magnetic body, the outer peripheral surface of the non-magnetic body having a first outer peripheral surface on which the first magnetic portion is provided, a second outer peripheral surface on which the second magnetic portion is provided, and a first intermediate outer peripheral surface provided between the first outer peripheral surface and the second outer peripheral surface, the first intermediate outer peripheral surface being positioned radially offset from each of the first outer peripheral surface and the second outer peripheral surface. In the resolver rotor according to the present invention, a groove extending in the circumferential direction of the non-magnetic body is formed on the outer circumferential surface of the non-magnetic body, and the first intermediate outer circumferential surface forms the bottom surface of the groove. In the resolver rotor according to the present invention, in each of the first magnetic portion and the second magnetic portion, the area per unit length along the circumferential direction of the non-magnetic body changes periodically in response to the change in circumferential position. In the resolver rotor of the present invention, the shapes of the first magnetic portion and the second magnetic portion when viewed from the radial direction are symmetrical to each other with respect to a plane that passes between the first magnetic portion and the second magnetic portion and is perpendicular to the axial direction. In the resolver rotor of the present invention, the periods of the periodic changes in the area per unit length along the circumferential direction in response to changes in circumferential position in the first magnetic portion and the second magnetic portion are identical to each other, and the phases of the periodic changes in the area per unit length along the circumferential direction in response to changes in circumferential position are shifted from each other. In the resolver rotor according to the present invention, the periods of the periodic changes in area per unit length along the circumferential direction in response to changes in circumferential position are different between the first magnetic portion and the second magnetic portion. In the resolver rotor according to the present invention, the area per unit length along the circumferential direction of each of the first magnetic portion and the second magnetic portion changes periodically in response to change in circumferential position due to the shape of the first intermediate outer peripheral surface. In the resolver rotor of the present invention, in the first magnetic portion, the area per unit length along the circumferential direction of the non-magnetic material changes periodically in accordance with changes in circumferential position, and in the second magnetic portion, the area per unit length along the circumferential direction is constant regardless of changes in circumferential position. In the resolver rotor of the present invention, the magnetic body has a third magnetic portion axially separated from the second magnetic portion, and the outer surface of the non-magnetic body has a third outer surface on which the third magnetic portion is provided, and a second intermediate outer surface provided between the second outer surface and the third outer surface, and the second intermediate outer surface is arranged radially shifted with respect to each of the second outer surface and the third outer surface. Effect of the Invention

[0010] According to the resolver rotor of the present invention, the first magnetic portion and the second magnetic portion can be provided on the outer circumferential surface of the non-magnetic body without increasing the size of the masking device that masks the outer circumferential surface of the non-magnetic body. [Brief description of the drawings]

[0011] [Figure 1] 1 is a plan view showing a resolver including a resolver rotor according to a first embodiment. FIG. [Diagram 2] FIG. 2 is a perspective view showing a resolver rotor shown in FIG. [Diagram 3] FIG. 11 is a perspective view showing a resolver rotor according to a second embodiment. [Figure 4] FIG. 11 is a perspective view showing a resolver rotor according to a third embodiment. [Diagram 5] FIG. 11 is a perspective view showing a resolver rotor according to a fourth embodiment. [Figure 6] FIG. 13 is a perspective view showing a resolver rotor according to a fifth embodiment. [Figure 7] FIG. 13 is a perspective view showing a resolver rotor according to a sixth embodiment. [Figure 8] FIG. 13 is a perspective view showing a resolver rotor according to a seventh embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0012] Embodiment 1 Fig. 1 is a plan view showing a resolver including a resolver rotor according to embodiment 1. Fig. 2 is a perspective view showing the resolver rotor of Fig. 1. The resolver includes a resolver stator 1 and a resolver rotor 2.

[0013] The resolver stator 1 includes a stator core 101 and a plurality of coils (not shown). The stator core 101 includes a ring-shaped core back 102 and a plurality of teeth 103 integrally provided on the core back 102. The plurality of teeth 103 are arranged at equal intervals in the circumferential direction of the core back 102. Each of the plurality of teeth 103 protrudes inward from the core back 102 in the radial direction of the core back 102. Each of the plurality of coils is wound around a corresponding one of the plurality of teeth 103.

[0014] The coils include an excitation coil and an output coil. The resolver angle measurement method includes, for example, a one-phase excitation two-phase output method, a two-phase excitation one-phase output method, and a two-phase excitation two-phase output method.

[0015] The resolver rotor 2 is provided rotatably relative to the resolver stator 1. The direction along the axis of the resolver rotor 2 is defined as the axial direction D1. The direction along the radius of a circle centered on the axis of the resolver rotor 2 in a plane perpendicular to the axis of the resolver rotor 2 is defined as the radial direction D2. The direction along the circumference of a circle centered on the axis of the resolver rotor 2 in a plane perpendicular to the axis of the resolver rotor 2 is defined as the circumferential direction D3.

[0016] The resolver rotor 2 includes a non-magnetic body 201 and a magnetic body 202 provided on the non-magnetic body 201 .

[0017] The non-magnetic body 201 is formed in a ring shape. The axial direction of the non-magnetic body 201 coincides with the axial direction D1. The radial direction of the non-magnetic body 201 coincides with the radial direction D2. The circumferential direction of the non-magnetic body 201 coincides with the circumferential direction D3.

[0018] When the non-magnetic body 201 is viewed in the axial direction D1, the outer peripheral surface 203 of the non-magnetic body 201 is a perfect circle. Therefore, the gap between the outer peripheral surface 203 of the non-magnetic body 201 and the teeth 103 is constant regardless of the rotational position of the resolver rotor 2 relative to the resolver stator 1.

[0019] The magnetic body 202 is provided on an outer circumferential surface 203 of the non-magnetic body 201. The magnetic body 202 has a first magnetic portion 204 and a second magnetic portion 205. The first magnetic portion 204 and the second magnetic portion 205 are separated from each other in the axial direction D1. By providing the first magnetic portion 204 and the second magnetic portion 205 on the outer circumferential surface 203 of the non-magnetic body 201, a magnetic path passing through the first magnetic portion 204 and a magnetic path passing through the second magnetic portion 205 are formed on the outer circumferential surface 203 of the non-magnetic body 201.

[0020] In each of the first magnetic portion 204 and the second magnetic portion 205, the area per unit length along the circumferential direction D3 changes periodically in response to the change in position in the circumferential direction D3.

[0021] Specifically, the area per unit length along the circumferential direction D3 of each of the first magnetic portion 204 and the second magnetic portion 205 changes periodically in a sinusoidal manner in response to the change in position in the circumferential direction D3.

[0022] As a result, the gap permeance between each of the first magnetic portion 204 and the teeth 103 and the second magnetic portion 205 changes periodically in a sinusoidal manner in response to a change in the position of the resolver rotor 2 relative to the resolver stator 1 in the circumferential direction D3.

[0023] When viewed from the radial direction D2, the shapes of the first magnetic portion 204 and the second magnetic portion 205 are symmetrical with respect to a plane that passes between the first magnetic portion 204 and the second magnetic portion 205 and is perpendicular to the axial direction D1.

[0024] Therefore, the periods of the periodic changes in the area per unit length along the circumferential direction D3 in response to the change in position in the circumferential direction D3 are the same in the first magnetic part 204 and the second magnetic part 205. Also, the phases of the periodic changes in the area per unit length along the circumferential direction D3 in response to the change in position in the circumferential direction D3 in the first magnetic part 204 and the second magnetic part 205 match each other.

[0025] The outer peripheral surface 203 of the non-magnetic body 201 has a first outer peripheral surface 206, a second outer peripheral surface 207, and a first intermediate outer peripheral surface 208. The first outer peripheral surface 206 and the second outer peripheral surface 207 are separated from each other in the axial direction D1. When viewed in the axial direction D1, the first outer peripheral surface 206 and the second outer peripheral surface 207 overlap each other.

[0026] The first outer peripheral surface 206 is provided with a first magnetic portion 204. The second outer peripheral surface 207 is provided with a second magnetic portion 205. The first intermediate outer peripheral surface 208 is provided between the first outer peripheral surface 206 and the second outer peripheral surface 207.

[0027] A groove 209 extending in the circumferential direction D3 is formed in the outer peripheral surface 203 of the non-magnetic body 201. The first intermediate outer peripheral surface 208 forms the bottom surface of the groove 209. Therefore, the first intermediate outer peripheral surface 208 is disposed so as to be shifted in the radial direction D2 with respect to each of the first outer peripheral surface 206 and the second outer peripheral surface 207.

[0028] Next, a description will be given of a procedure for manufacturing the resolver rotor 2. First, the areas on the outer peripheral surface 203 of the non-magnetic body 201 other than the areas where the first magnetic portion 204 and the second magnetic portion 205 are provided are masked. A masking device (not shown) that masks the outer peripheral surface 203 of the non-magnetic body 201 has a first masking portion and a second masking portion.

[0029] The first mask portion masks an area of ​​the first outer peripheral surface 206 other than the area where the first magnetic portion 204 is provided. The second mask portion masks an area of ​​the second outer peripheral surface 207 other than the area where the second magnetic portion 205 is provided. The first mask portion and the second mask portion sandwich the non-magnetic body 201 in the axial direction D1, thereby masking the outer peripheral surface 203 of the non-magnetic body 201. Note that the first intermediate outer peripheral surface 208 is not masked.

[0030] Thereafter, while rotating the non-magnetic body 201 in the circumferential direction D3, molten magnetic material powder is sprayed from a nozzle of a metal spraying machine onto the outer circumferential surface 203 of the non-magnetic body 201. As a result, a first magnetic portion 204 is provided on the first outer circumferential surface 206, and a second magnetic portion 205 is provided on the second outer circumferential surface 207. At this time, the molten magnetic material powder is also provided on the first intermediate outer circumferential surface 208.

[0031] Since the first intermediate outer peripheral surface 208 forms the bottom surface of the groove 209, the effect of the magnetic material powder provided on the first intermediate outer peripheral surface 208 on the gap permeance between the resolver stator 1 and the resolver rotor 2 is reduced.

[0032] The spraying of the molten magnetic material powder onto the outer peripheral surface 203 of the non-magnetic body 201 is performed in a single spraying process. Therefore, a magnetic path passing through the first magnetic portion 204 and a magnetic path passing through the second magnetic portion 205 are formed on the outer peripheral surface 203 of the non-magnetic body 201 by the single spraying process.

[0033] Thereafter, the first mask portion and the second mask portion are removed from the outer circumferential surface 203 of the non-magnetic body 201. With the above, the manufacturing process of the resolver rotor 2 is completed.

[0034] As described above, the resolver rotor 2 according to the first embodiment includes the non-magnetic body 201 formed in a ring shape and the magnetic body 202 provided on the outer circumferential surface 203 of the non-magnetic body 201. The magnetic body 202 has a first magnetic portion 204 and a second magnetic portion 205 spaced apart from the first magnetic portion 204 in the axial direction D1. The outer circumferential surface 203 of the non-magnetic body 201 has a first outer circumferential surface 206 on which the first magnetic portion 204 is provided, a second outer circumferential surface 207 on which the second magnetic portion 205 is provided, and a first intermediate outer circumferential surface 208 provided between the first outer circumferential surface 206 and the second outer circumferential surface 207. The first intermediate outer circumferential surface 208 is disposed so as to be shifted in the radial direction D2 with respect to each of the first outer circumferential surface 206 and the second outer circumferential surface 207. According to this configuration, it is not necessary to mask the area between the first magnetic portion 204 and the second magnetic portion 205 on the outer peripheral surface 203 of the non-magnetic body 201. As a result, the masking device that masks the outer peripheral surface 203 of the non-magnetic body 201 does not need to be configured to have a third masking portion that masks the area between the first magnetic portion 204 and the second magnetic portion 205 on the outer peripheral surface 203 of the non-magnetic body 201. As a result, the first magnetic portion 204 and the second magnetic portion 205 can be provided on the outer peripheral surface 203 of the non-magnetic body 201 without increasing the size of the masking device that masks the outer peripheral surface 203 of the non-magnetic body 201.

[0035] Moreover, in the resolver rotor 2 according to the first embodiment, a groove 209 extending in the circumferential direction D3 is formed in the outer peripheral surface 203 of the non-magnetic body 201, and the first intermediate outer peripheral surface 208 serves as the bottom surface of the groove 209. With this configuration, the effect of the magnetic material powder provided on the first intermediate outer peripheral surface 208 on the gap permeance between the resolver stator 1 and the resolver rotor 2 can be reduced.

[0036] Moreover, in the resolver rotor 2 according to the first embodiment, the area per unit length along the circumferential direction D3 of each of the first magnetic portion 204 and the second magnetic portion 205 changes periodically in response to a change in position in the circumferential direction D3. According to this configuration, the resolver stator 1 can obtain two different signals corresponding to the gap permeance between the resolver stator 1 and the resolver rotor 2. This can improve the measurement accuracy of the resolver.

[0037] In the resolver rotor 2 according to the first embodiment, the shapes of the first magnetic portion 204 and the second magnetic portion 205 when viewed from the radial direction D2 are symmetrical with respect to a plane that passes between the first magnetic portion 204 and the second magnetic portion 205 and is perpendicular to the axial direction D1. With this configuration, the outer circumferential surface 203 of the non-magnetic body 201 can be masked using a mask device including a first mask portion and a second mask portion formed in the same shape. This makes it possible to easily manufacture a mask device that masks the outer circumferential surface 203 of the non-magnetic body 201.

[0038] Embodiment 2 3 is a perspective view showing a resolver rotor according to embodiment 2. In the resolver rotor 2 according to embodiment 2, the area per unit length along the circumferential direction D3 in the second magnetic portion 205 is constant regardless of the change in position in the circumferential direction D3.

[0039] When eccentricity occurs in the position of the resolver rotor 2 relative to the resolver stator 1, the gap between the teeth 103 and the second magnetic portion 205 changes in response to the amount of eccentricity of the resolver rotor 2 relative to the resolver stator 1. The resolver can measure the amount of eccentricity of the resolver rotor 2 relative to the resolver stator 1 by using the gap permeance between the teeth 103 and the second magnetic portion 205.

[0040] Other configurations of the resolver rotor 2 according to the second embodiment are similar to those of the resolver rotor 2 according to the first embodiment.

[0041] As described above, in the resolver rotor 2 according to the second embodiment, in the first magnetic portion 204, the area per unit length along the circumferential direction D3 changes periodically in response to changes in position in the circumferential direction D3. In the second magnetic portion 205, the area per unit length along the circumferential direction D3 is constant regardless of changes in position in the circumferential direction D3. With this configuration, the amount of eccentricity of the resolver rotor 2 with respect to the resolver stator 1 can be measured using the gap permeance between the teeth 103 and the second magnetic portion 205.

[0042] Embodiment 3 4 is a perspective view showing a resolver rotor according to embodiment 3. In the resolver rotor 2 according to embodiment 3, the magnetic body 202 has a third magnetic portion 210 separated from the second magnetic portion 205 in the axial direction D1. The first magnetic portion 204, the second magnetic portion 205, and the third magnetic portion 210 are arranged in the axial direction D1 in the order of the first magnetic portion 204, the second magnetic portion 205, and the third magnetic portion 210.

[0043] The outer peripheral surface 203 of the non-magnetic body 201 has a third outer peripheral surface 211 and a second intermediate outer peripheral surface 212. The second outer peripheral surface 207 and the third outer peripheral surface 211 are separated from each other in the axial direction D1. When viewed in the axial direction D1, the second outer peripheral surface 207 and the third outer peripheral surface 211 overlap each other.

[0044] The third outer peripheral surface 211 is provided with the third magnetic portion 210. The second intermediate outer peripheral surface 212 is provided between the second outer peripheral surface 207 and the third outer peripheral surface 211.

[0045] A groove 213 extending in the circumferential direction D3 is formed in the outer peripheral surface 203 of the non-magnetic body 201. The second intermediate outer peripheral surface 212 forms the bottom surface of the groove 213. Therefore, the second intermediate outer peripheral surface 212 is disposed so as to be shifted in the radial direction D2 with respect to each of the second outer peripheral surface 207 and the third outer peripheral surface 211.

[0046] In the third magnetic unit 210, the area per unit length along the circumferential direction D3 changes periodically in response to the change in position in the circumferential direction D3.

[0047] Specifically, the area per unit length in the circumferential direction D3 of the third magnetic unit 210 changes periodically in a sinusoidal manner in response to the change in position in the circumferential direction D3.

[0048] As a result, the gap permeance between each of the third magnetic portions 210 and the teeth 103 changes periodically in a sinusoidal manner in response to a change in the position of the resolver rotor 2 relative to the resolver stator 1 in the circumferential direction D3.

[0049] Other configurations of the resolver rotor 2 according to the third embodiment are similar to those of the resolver rotor 2 according to the second embodiment.

[0050] As described above, in the resolver rotor 2 according to the third embodiment, the magnetic body 202 has the third magnetic portion 210 separated from the second magnetic portion 205 in the axial direction D1. The outer peripheral surface 203 of the non-magnetic body 201 has the third outer peripheral surface 211 on which the third magnetic portion 210 is provided, and the second intermediate outer peripheral surface 212 provided between the second outer peripheral surface 207 and the third outer peripheral surface 211. The second intermediate outer peripheral surface 212 is disposed so as to be shifted in the radial direction D2 from each of the second outer peripheral surface 207 and the third outer peripheral surface 211. According to this configuration, the resolver stator 1 can obtain two different signals corresponding to the gap permeance between the resolver stator 1 and the resolver rotor 2, and the eccentricity of the resolver rotor 2 relative to the resolver stator 1 can be measured.

[0051] In the resolver rotor 2 according to the third embodiment, the groove 213 extending in the circumferential direction D3 is formed on the outer circumferential surface 203 of the non-magnetic body 201, and the second intermediate outer circumferential surface 212 serves as the bottom surface of the groove 213. However, the resolver rotor 2 according to the third embodiment may have a configuration in which a convex portion extending in the circumferential direction D3 is formed on the outer circumferential surface 203 of the non-magnetic body 201, and the second intermediate outer circumferential surface 212 serves as the top surface of the convex portion.

[0052] Embodiment 4 5 is a perspective view showing a resolver rotor according to embodiment 4. In the resolver rotor 2 according to embodiment 4, the first magnetic portion 204 has a plurality of trapezoidal portions 214 and a plurality of connecting portions 215.

[0053] The multiple trapezoidal portions 214 are arranged at equal intervals in the circumferential direction D3. Each of the multiple trapezoidal portions 214 is formed in a trapezoidal shape when viewed in the radial direction D2. The portions of the trapezoidal portion 214 corresponding to a pair of parallel sides of the trapezoid are aligned along the circumferential direction D3. The portion of the trapezoidal portion 214 corresponding to the short side of the pair of parallel sides of the trapezoid is farther from the first intermediate outer circumferential surface 208 in the axial direction D1 than the portion of the trapezoidal portion 214 corresponding to the long side.

[0054] The multiple connecting portions 215 are disposed one by one between each of the multiple trapezoidal portions 214 aligned in the circumferential direction D3. The connecting portions 215 are connected to each of a pair of trapezoidal portions 214 aligned in the circumferential direction D3. The connecting portions 215 are connected to portions of the trapezoidal portions 214 corresponding to the longer sides of a pair of parallel sides of the trapezoid. Therefore, the connecting portions 215 are provided on a portion of the first outer peripheral surface 206 on the first intermediate outer peripheral surface 208 side when viewed in the radial direction D2.

[0055] The second magnetic portion 205 has a plurality of trapezoidal portions 216 and a plurality of connecting portions 217 .

[0056] The multiple trapezoidal portions 216 are arranged at equal intervals in the circumferential direction D3. Each of the multiple trapezoidal portions 216 is formed in a trapezoidal shape when viewed in the radial direction D2. A portion of the trapezoidal portion 216 corresponding to a pair of parallel sides of the trapezoid is aligned along the circumferential direction D3. A portion of the trapezoidal portion 216 corresponding to a short side of the pair of parallel sides of the trapezoid is farther from the first intermediate outer circumferential surface 208 in the axial direction D1 than a portion of the trapezoidal portion 216 corresponding to a long side.

[0057] The multiple connecting portions 217 are disposed one by one between each of the multiple trapezoidal portions 216 aligned in the circumferential direction D3. The connecting portion 217 is connected to each of a pair of trapezoidal portions 216 aligned in the circumferential direction D3. The connecting portion 217 is connected to a portion of the trapezoidal portion 216 corresponding to a longer side of a pair of parallel sides of the trapezoid. Therefore, the connecting portion 217 is provided on a portion of the second outer peripheral surface 207 on the first intermediate outer peripheral surface 208 side when viewed in the radial direction D2.

[0058] Other configurations of the resolver rotor 2 according to the fourth embodiment are similar to those of the resolver rotor 2 according to the first embodiment.

[0059] As described above, in the resolver rotor 2 according to the fourth embodiment, similarly to the resolver rotor 2 according to the first embodiment, it is not necessary to mask the region between the first magnetic portion 204 and the second magnetic portion 205 on the outer circumferential surface 203 of the non-magnetic body 201. As a result, the mask device that masks the outer circumferential surface 203 of the non-magnetic body 201 does not need to be configured to have a third mask portion that masks the region between the first magnetic portion 204 and the second magnetic portion 205 on the outer circumferential surface 203 of the non-magnetic body 201. As a result, the first magnetic portion 204 and the second magnetic portion 205 can be provided on the outer circumferential surface 203 of the non-magnetic body 201 without increasing the size of the mask device that masks the outer circumferential surface 203 of the non-magnetic body 201.

[0060] Embodiment 5. 6 is a perspective view showing a resolver rotor according to embodiment 5. In the resolver rotor 2 according to embodiment 5, the periods of the periodic changes in the area per unit length along the circumferential direction D3 in the first magnetic portion 204 and the second magnetic portion 205 according to the change in position in the circumferential direction D3 are different from each other.

[0061] Specifically, in the first magnetic part 204, the periodic change in area per unit length along the circumferential direction D3 in response to the change in position in the circumferential direction D3 occurs only four times in the entire area of ​​the circumferential direction D3. On the other hand, in the second magnetic part 205, the periodic change in area per unit length along the circumferential direction D3 in response to the change in position in the circumferential direction D3 occurs only seven times in the entire area of ​​the circumferential direction D3.

[0062] Other configurations of the resolver rotor 2 according to the fifth embodiment are similar to those of the resolver rotor 2 according to the first embodiment.

[0063] As described above, in the resolver rotor 2 according to the fifth embodiment, the periods of the periodic changes in the area per unit length along the circumferential direction D3 corresponding to the change in position in the circumferential direction D3 are different from each other in the first magnetic portion 204 and the second magnetic portion 205. According to this configuration, the position of the resolver rotor 2 in the circumferential direction D3 relative to the resolver stator 1 can be measured more accurately.

[0064] Embodiment 6 7 is a perspective view showing a resolver rotor according to a sixth embodiment. In the resolver rotor 2 according to the sixth embodiment, the periods of the periodic changes in the area per unit length along the circumferential direction D3 in the first magnetic portion 204 and the second magnetic portion 205 corresponding to the change in position in the circumferential direction D3 are the same. In the resolver rotor 2 according to the sixth embodiment, the phases of the periodic changes in the area per unit length along the circumferential direction D3 in the first magnetic portion 204 and the second magnetic portion 205 corresponding to the change in position in the circumferential direction D3 are shifted from each other.

[0065] Specifically, in the first magnetic part 204 and the second magnetic part 205, the periodic changes in the area per unit length along the circumferential direction D3 in response to the change in position in the circumferential direction D3 occur only four times in the entire area of ​​the circumferential direction D3. Also, in the first magnetic part 204 and the second magnetic part 205, the periodic changes in the area per unit length along the circumferential direction D3 in response to the change in position in the circumferential direction D3 are shifted from each other by 45 degrees in the circumferential direction D3.

[0066] Other configurations of the resolver rotor 2 according to the sixth embodiment are similar to those of the resolver rotor 2 according to the first embodiment.

[0067] As described above, in the resolver rotor 2 according to the sixth embodiment, the periods of the periodic changes in the area per unit length along the circumferential direction D3 in the first magnetic portion 204 and the second magnetic portion 205 corresponding to the change in position in the circumferential direction D3 are the same. Also, the phases of the periodic changes in the area per unit length along the circumferential direction D3 in the first magnetic portion 204 and the second magnetic portion 205 corresponding to the change in position in the circumferential direction D3 in the area per unit length along the circumferential direction D3 are shifted from each other. With this configuration, the position of the resolver rotor 2 in the circumferential direction D3 relative to the resolver stator 1 can be measured more accurately.

[0068] Embodiment 7 8 is a perspective view showing a resolver rotor according to embodiment 7. In the resolver rotor 2 according to embodiment 7, the area per unit length along the circumferential direction D3 of each of the first magnetic portion 204 and the second magnetic portion 205 changes periodically in response to a change in position in the circumferential direction D3 due to the shape of the first intermediate outer circumferential surface 208.

[0069] In other words, in the first intermediate outer circumferential surface 208, the area per unit length along the circumferential direction D3 changes periodically in accordance with the change in position in the circumferential direction D3.

[0070] Other configurations of the resolver rotor 2 according to the seventh embodiment are similar to those of the resolver rotor 2 according to the first embodiment.

[0071] As described above, in the resolver rotor 2 according to the seventh embodiment, the area per unit length along the circumferential direction D3 of each of the first magnetic portion 204 and the second magnetic portion 205 changes periodically in response to a change in position in the circumferential direction D3 due to the shape of the first intermediate outer circumferential surface 208. With this configuration, when providing the first magnetic portion 204 and the second magnetic portion 205 on the outer circumferential surface 203 of the non-magnetic body 201, it is not necessary to mask the outer circumferential surface 203 of the non-magnetic body 201. This makes it possible to manufacture the resolver rotor 2 more easily.

[0072] In the resolver rotor 2 according to each embodiment, the groove 209 extending in the circumferential direction D3 is formed on the outer circumferential surface 203 of the non-magnetic body 201, and the first intermediate outer circumferential surface 208 serves as the bottom surface of the groove 209. However, a configuration may also be used in which a convex portion extending in the circumferential direction D3 is formed on the outer circumferential surface 203 of the non-magnetic body 201, and the first intermediate outer circumferential surface 208 serves as the top surface of the convex portion.

[0073] In addition, in the resolver rotors 2 according to the first, second, third, fifth, sixth and seventh embodiments, the configuration has been described in which the area per unit length along the circumferential direction D3 in the first magnetic portion 204 periodically changes in a sinusoidal manner in response to a change in position in the circumferential direction D3. However, any configuration may be used as long as the area per unit length along the circumferential direction D3 in the first magnetic portion 204 periodically changes in response to a change in position in the circumferential direction D3.

[0074] In addition, in the resolver rotors 2 according to the first, fifth, sixth and seventh embodiments, the configuration has been described in which the area per unit length along the circumferential direction D3 in the second magnetic portion 205 periodically changes in a sinusoidal manner in response to a change in position in the circumferential direction D3. However, any configuration may be used as long as the area per unit length along the circumferential direction D3 in the second magnetic portion 205 periodically changes in response to a change in position in the circumferential direction D3.

[0075] In the resolver rotor 2 according to the third embodiment, the area per unit length along the circumferential direction D3 in the third magnetic portion 210 periodically changes sinusoidally in response to a change in position in the circumferential direction D3. However, any configuration may be used as long as the area per unit length along the circumferential direction D3 in the third magnetic portion 210 periodically changes in response to a change in position in the circumferential direction D3.

[0076] Although the resolver rotor 2 according to each preferred embodiment has been described above, the resolver rotor 2 according to each of the above-mentioned embodiments is not limited to the above-mentioned embodiments. Various modifications and conversions can be made to the resolver rotor 2 according to each of the above-mentioned embodiments without departing from the scope of the claims. [Explanation of symbols]

[0077] 1 resolver stator, 2 resolver rotor, 101 stator core, 102 core back, 103 teeth, 201 non-magnetic body, 202 magnetic body, 203 outer peripheral surface, 204 first magnetic portion, 205 second magnetic portion, 206 first outer peripheral surface, 207 second outer peripheral surface, 208 first intermediate outer peripheral surface, 209 groove, 210 third magnetic portion, 211 third outer peripheral surface, 212 second intermediate outer peripheral surface, 213 groove, 214 trapezoidal portion, 215 connecting portion, 216 trapezoidal portion, 217 connecting portion.

Claims

1. a ring-shaped non-magnetic body (201); a magnetic body (202) provided on the outer peripheral surface (203) of the non-magnetic body (201); Equipped with The magnetic body (202) has a first magnetic portion (204) and a second magnetic portion (205) spaced apart from the first magnetic portion (204) in the axial direction of the non-magnetic body (201), The outer peripheral surface (203) of the non-magnetic body (201) has a first outer peripheral surface (206) on which the first magnetic portion (204) is provided, a second outer peripheral surface (207) on which the second magnetic portion (205) is provided, and a first intermediate outer peripheral surface (208) provided between the first outer peripheral surface (206) and the second outer peripheral surface (207), The resolver rotor is arranged so that the first intermediate outer peripheral surface (208) is shifted in the radial direction of the non-magnetic body (201) relative to each of the first outer peripheral surface (206) and the second outer peripheral surface (207).

2. A groove (209) extending in the circumferential direction of the non-magnetic body (201) is formed on the outer peripheral surface (203) of the non-magnetic body (201), 2. The resolver rotor according to claim 1, wherein the first intermediate outer peripheral surface (208) forms a bottom surface of the groove (209).

3. 3. The resolver rotor according to claim 1, wherein in each of the first magnetic portion and the second magnetic portion, an area per unit length along a circumferential direction of the non-magnetic body changes periodically in accordance with a change in position in the circumferential direction.

4. 4. The resolver rotor according to claim 3, wherein the shapes of the first magnetic portion (204) and the second magnetic portion (205) when viewed from the radial direction are plane-symmetrical with respect to a plane that passes between the first magnetic portion (204) and the second magnetic portion (205) and is perpendicular to the axial direction.

5. 4. The resolver rotor according to claim 3, wherein in the first magnetic portion (204) and the second magnetic portion (205), periods of periodic changes in area per unit length along the circumferential direction in response to changes in circumferential position are identical to each other, and phases of periodic changes in area per unit length along the circumferential direction in response to changes in circumferential position are shifted from each other.

6. The resolver rotor according to claim 3, wherein the periods of the periodic changes in the area per unit length along the circumferential direction in response to changes in the circumferential position in the first magnetic portion (204) and the second magnetic portion (205) are different from each other.

7. 4. The resolver rotor according to claim 3, wherein the shape of the first intermediate outer peripheral surface (208) causes the area per unit length along the circumferential direction of each of the first magnetic portion (204) and the second magnetic portion (205) to periodically change in accordance with a change in position in the circumferential direction.

8. In the first magnetic portion (204), the area per unit length along the circumferential direction of the non-magnetic body (201) periodically changes in accordance with the change in the position in the circumferential direction, 3. The resolver rotor according to claim 1, wherein the area per unit length along the circumferential direction of the second magnetic portion is constant regardless of a change in position in the circumferential direction.

9. The magnetic body (202) has a third magnetic portion (210) spaced apart from the second magnetic portion (205) in the axial direction, the outer peripheral surface (203) of the non-magnetic body (201) has a third outer peripheral surface (211) on which the third magnetic portion (210) is provided, and a second intermediate outer peripheral surface (212) provided between the second outer peripheral surface (207) and the third outer peripheral surface (211); 2. The resolver rotor according to claim 1, wherein the second intermediate outer peripheral surface (212) is disposed so as to be shifted in the radial direction with respect to each of the second outer peripheral surface (207) and the third outer peripheral surface (211).

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