JP2013072673A - Rotor of vr type resolver and vr type resolver - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a structure in which a relief groove does not adversely affect characteristics of a resolver even when the relief groove for avoiding interference with a recessed edge of a rotary shaft is provided on a root part of a projection part, in a detent structure in which the projection part on a rotor inner side and a recessed part provided on the rotary shaft are fitted.SOLUTION: A rotor 100 of a VR type resolver includes: a hollow part 101 for attaching a shaft; a projection part 106 projected in a direction of a rotation center from an inner peripheral surface of the hollow part 101; and relief grooves 107 and 108 which are formed at the root part of the projection part 106, are not recessed in a direction of separating from the rotation center, and are recessed in a direction of the inside of the projection part.

Description

  The present invention relates to a VR resolver rotor characterized by a structure fixed to a rotating shaft.

  Patent Document 1 discloses a structure of a VR type resolver rotor that is provided with a convex portion on the inner side of the rotor to prevent rotation with a rotating shaft. Patent Document 1 discloses a structure in which relief recesses that are recessed toward the direction away from the rotation center of the rotor are provided on both sides of the convex portion inside the rotor as relief grooves such as burrs at the edge of the recess of the rotation shaft. Is described.

JP 2002-174535 A

  In the structure described in Patent Document 1, since the escape recess is recessed in the direction away from the rotation center, the thickness of the rotor is partially reduced at that portion. In the VR resolver, a detection coil (output winding) on the stator side detects a periodic change in the gap permeance between the rotor and the stator caused by the rotation of the rotor having a nonuniform radial thickness. In the RD converter, the rotation angle of the rotor is calculated.

  Here, if the thickness of the rotor is partially thin, the cross-sectional area of the magnetic path becomes narrow at that portion, so that the magnetic resistance at that portion becomes high. The portion where the magnetic resistance is partially increased does not exist in the rotor in a well-balanced manner. Therefore, the presence of the detected waveform (a waveform of a voltage that periodically changes induced in the sin detection winding and the cos detection winding) causes the periodicity to collapse from an ideal state.

  The VR type resolver is configured to rotate the rotor in the RD converter based on a change in induced voltage indicating a sine curve detected from a sin detection winding and a change in induced voltage indicating a cosine curve detected from a cos detection winding. The angle is calculated. If the detected voltage change of the sine curve and the voltage change of the cosine curve are deviated from the ideal sine curve and cosine curve, it becomes an angle detection error.

  Therefore, a partial increase in the magnetic resistance inside the rotor due to the presence of the escape recesses adversely affects the resolver characteristics. This tendency becomes particularly prominent when the escape groove is formed in a portion where the rotor is thin. That is, if the escape recess is provided in the thin part, the part provided with the escape recess is further thinned, and the deterioration of the angle detection accuracy due to the above-described reason becomes more remarkable.

  In such a background, the present invention provides a non-rotating structure in which the protrusion inside the rotor and the recess provided on the rotation shaft are fitted to each other, and interference between the root of the protrusion and the recess edge of the rotation shaft is caused. An object is to provide a structure in which the escape groove does not adversely affect the characteristics of the resolver even if the escape groove to be avoided is provided.

  The invention according to claim 1 is formed in a hollow portion for attaching the shaft, a protrusion protruding in the direction of the rotation center from the inner peripheral surface of the hollow portion, and a root portion of the protrusion, The rotor of the VR type resolver is characterized by having a groove that is not recessed in the direction away from the groove but is recessed in the direction inside the protrusion. According to the first aspect of the present invention, since the groove is not recessed in the direction away from the center of rotation, the thickness of the rotor is not partially reduced in the portion where the groove is provided, and the rotor inside in the operating state. Thus, the magnetic path formed is not partially narrowed. Therefore, the deterioration of the resolver characteristics due to the formation of the grooves can be suppressed.

  According to a second aspect of the present invention, in the first aspect of the invention, the rotor has a thick portion and a thin portion that are relatively thick when viewed from the axial direction, and the protrusion The portion is provided at a position avoiding the thick portion. According to the second aspect of the present invention, the protrusions for fitting with the recesses on the rotating shaft side are provided in the thin part as compared with the part where the thickness of the rotor is maximum, and interference prevention is provided on both sides thereof. Even if the relief groove is provided, deterioration of the resolver characteristics can be suppressed.

  According to a third aspect of the present invention, in the second aspect of the present invention, the protrusion is provided on the thin portion. According to the third aspect of the present invention, even if the convex portions and the relief grooves on both sides thereof are provided in the thinnest portion, the resolver characteristics are not deteriorated.

  A fourth aspect of the present invention is a VR resolver using the rotor according to any one of the first to third aspects.

  According to the present invention, in the non-rotating structure in which the protrusion inside the rotor and the recess provided on the rotation shaft are fitted, the relief groove that avoids interference with the recess edge of the rotation shaft is formed at the root of the protrusion. Even if provided, a structure is provided in which the escape groove does not adversely affect the characteristics of the resolver.

It is sectional drawing (A) of the rotor of VR type | mold resolver in embodiment of invention, and sectional drawing (B) which expanded the part. It is sectional drawing of a shaft. It is sectional drawing which looked at the state which attached the shaft to the rotor from the axial direction. It is sectional drawing (A) of the rotor in a prior art, and sectional drawing (B) of the rotor using invention. They are a sectional view (A) of a rotor of a VR type resolver in another embodiment and a sectional view (B) in which a part thereof is enlarged.

(1) First Embodiment FIG. 1 is a cross-sectional view of a rotor 100 of a VR resolver according to an embodiment of the invention. FIG. 1 shows a cross-sectional state of the rotor 100 viewed from the axial direction. 1A shows the whole, and FIG. 1B shows a cross-sectional structure in which a part is enlarged. The rotor 100 has a structure in which a thin plate (for example, a silicon steel plate or an electromagnetic steel plate) made of a soft magnetic material is processed into a shape shown in the drawing, and a plurality of such layers are stacked in the axial direction. The rotor 100 is a rotor for a VR resolver having a shaft angle multiplier of 2 ×, and has two portions (upper and lower portions in the figure) that become magnetic poles protruding in a direction away from the rotation center. That is, the rotor 100 has a relative relationship between the first thick portion 102 constituting the first magnetic pole, the second thick portion 103 constituting the second magnetic pole, and the portion between the thick portions 102 and 103. It has thin portions 104 and 105 that are thinnest.

  The rotor 100 is formed with a hollow portion 101 into which a shaft serving as a rotation shaft is fitted. The hollow portion 101 is provided with a convex portion 106 that is a protruding portion that protrudes from the inner surface side (the inner peripheral surface on the shaft side) of the thick portion 102 in the direction of the rotation center (axial center). In FIG. 1B, the convex portion 106 is shown in an enlarged manner.

  As shown in FIG. 1B, relief grooves 107 and 108 that are recessed in the circumferential direction are provided at the bases of both side surfaces of the convex portion 106. Here, a broken line 109 is an extension line of the inner diameter surface of the rotor 100. Here, the inner diameter surface is a surface inside the rotor 100 where the inner diameter of the hollow portion 101 is constant. The escape grooves 107 and 108 are recessed in the circumferential direction and have a structure that does not extend outside the broken line 109 (in a direction away from the rotation center). That is, the escape grooves 107 and 108 have a structure that is not recessed in the direction away from the center of rotation but recessed in the direction of the inside of the convex portion 106. The axial length of the convex portion 106 may be the same as the axial length of the rotor 100 or may be a partial length of the rotor 100 in the axial direction.

  FIG. 2 shows a cross-sectional view of the shaft 201 fitted in the hollow portion 101 as seen from the axial direction. The shaft 201 is a columnar member that serves as a rotation axis of the rotor 100. A recess 202 is provided on the outer peripheral surface of the shaft 201. The concave portion 202 has a shape that meshes with the convex portion 106 of the rotor 100. By engaging the convex portion 106 of the rotor 100 with the concave portion 202, a structure in which one of the rotor 100 and the shaft 201 is not rotated (idling) relative to the other in the coupled state is obtained.

  3 shows a state in which the shaft 201 of FIG. 2 is inserted into the hollow portion 101 of the rotor 100 of FIG. 1 and the shaft 201 and the rotor 100 are coupled. 3A shows the whole, and FIG. 3B shows an enlarged cross-sectional state of a portion where the convex portion 106 on the rotor 100 side and the concave portion 202 of the shaft 201 are engaged with each other.

  Hereinafter, the reason why the escape grooves 107 and 108 are provided will be described. FIG. 4A shows a cross section when the convex portion 106 is formed without forming the relief grooves 108 and 109. FIG. 4B shows a cross section when the relief grooves 108 and 109 are formed in the structure shown in FIG. Here, a state obtained by a method of processing an electromagnetic steel plate or a silicon steel plate into a shape shown in the drawing by pressing is shown. In addition, about a processing method, it is not limited to press processing, You may use wire cut processing.

  In the state shown in FIG. 4A, the corner portions 401 and 402 do not accurately reproduce the shape of the press mold, but are R portions with R. This is because the shape of the corner portion does not become the same as the shape of the edge of the press die due to slight deformation of the steel plate during press working, and in the case of press working, the corner portion is reduced in order to reduce the consumption of the die. This is because, in the case of wire-cut processing, it becomes R depending on the wire diameter and becomes round.

  On the other hand, since the concave portion 202 in the shaft 201 of FIG. 2 is formed by cutting, the edges of the edge portions 203 and 204 of the concave portion 202 have an intended shape with high reproducibility. Therefore, when the shaft 201 of FIG. 2 is inserted into the hollow portion 101 of the rotor 100 in the state shown in FIG. 4A, the portions of the R portions 401 and 402 and the edge portions 203 and 204 of the recess 202 interfere with each other. However, there arises a problem that the rotor 100 and the shaft 201 cannot be smoothly coupled.

  Here, by adopting a structure in which the relief grooves 108 and 109 shown in FIG. 1 and FIG. 4B are formed on the rotor 100 side, the above problem is solved. That is, by forming the relief grooves 108 and 109 in FIG. 4B, the corner portion is processed into a shape that is excessively depressed, so that the R portion 401 in FIG. A portion corresponding to 402 is not formed. This solves the problem that the rotor 100 and the shaft 201 cannot be smoothly connected. For some reason, even if burrs are generated in the portions 203 and 204 on the shaft 201 side in FIG. 2, the burrs escape to the portions of the escape grooves 108 and 109 shown in FIGS. 1 and 4B. There is no problem that the rotor 100 and the shaft 201 cannot be smoothly connected due to the presence of burrs.

  For the above reasons, the escape grooves 107 and 108 are provided. The relief grooves 107 and 108 are generally formed at the same time as pressing, but additional processing is performed after the shape shown in FIG. 4 (A) is obtained, as shown in FIG. 4 (B). A method of obtaining the shape is also possible.

(2) 2nd Embodiment The position of the convex part provided inside a rotor is not limited to the case of FIG. Hereinafter, this example will be described. FIG. 5 shows the rotor 500. The rotor 500 is a VR resolver rotor having a shaft angle multiplier of 2 ×, similar to the rotor 100 of FIG. 1. The rotor 500 has a hollow portion 501 into which a shaft is inserted, thick portions 502 and 503, and thin portions 504 and 505. The thick portions 502 and 503 are portions that serve as the magnetic poles of the rotor, and the thin portions 504 and 505 are relatively thin portions that connect the portions between the thick portions 502 and 503.

  In this example, the convex portion 506 is provided on the inner side (rotation center side) of the thin portion 504. Relief grooves 507 and 508 that are recessed in the circumferential direction are provided at the base portions of both side surfaces of the convex portion 506. The structure of the convex portion 506 and the relief grooves 507 and 508 is the same as that of the convex portion 106 and the relief grooves 107 and 108 in FIG. Also in this case, a concave portion that fits into the convex portion 506 is provided on the shaft (not shown) side. When the rotor 501 and the shaft (not shown) are combined, the convex portion 506 is fitted into the shaft-side recess (not shown).

  In this example, a convex portion 506 is provided inside the thin portion 504 where the thickness of the rotor 500 is the thinnest, and relief grooves 507 and 508 are further provided in that portion. If the relief grooves 507 and 508 are provided so as to extend outward (in the direction away from the rotation center) from the extension line 509 of the rotor inner diameter surface, a portion where the thickness is further reduced is formed in the thin portion 504. As a result, the possibility of adversely affecting the resolver characteristics increases. However, as shown in FIG. 5B, the escape grooves 507 and 508 are not extended outward from the extension line 509 of the rotor inner surface, but are stopped on the inner side, and the direction of the recess of the escape groove is the circumferential direction. Thus, the thinned portion 504 is not partially formed with a portion where the thickness is further reduced. Therefore, it is possible to suppress the occurrence of adverse effects on the resolver characteristics due to the formation of a part that is further thinner in the thin part 504.

(3) Third Embodiment A VR resolver using the rotor 100 of FIG. 1 or the rotor 500 of FIG. 5 will be described. In this case, parts other than the structure of the rotor are the same as those of a VR resolver having a normal shaft angle multiplier of 2X. Briefly, the VR resolver in this case is arranged in a state where the rotor 100 or the rotor 500 is rotatable inside a stator (not shown) in which the excitation winding, the sin detection winding, and the cos detection winding are arranged. Is done. Inside the stator (not shown), a plurality of salient poles wound with the windings are arranged, and the rotor 100 or 500 is rotatably held at a position spaced from the tip of the salient pole.

(Other)
The number of the convex part 106 and the convex part 506 is not limited to one, A plurality may be sufficient. In the embodiment, the example of the rotor when the shaft double angle is 2X is shown, but the number of the shaft double angle can be arbitrarily set. The aspect of the present invention is not limited to the individual embodiments described above, and includes various modifications that can be conceived by those skilled in the art, and the effects of the present invention are not limited to the contents described above. That is, various additions, modifications, and partial deletions can be made without departing from the concept and spirit of the present invention derived from the contents defined in the claims and equivalents thereof.

  The present invention can be used for a VR resolver.

  DESCRIPTION OF SYMBOLS 100 ... Rotor, 101 ... Hollow part, 102 ... Thick part, 103 ... Thick part, 104 ... Thin part, 105 ... Thin part, 106 ... Convex part, 107 ... Relief groove, 108 ... Relief groove, 109 ... Rotor inner diameter Surface extension line, 201 ... shaft, 202 ... recess, 203 ... edge part, 204 ... edge part, 500 ... rotor, 501 ... hollow part, 502 ... thick part, 503 ... thick part, 504 ... thin part, 505 ... Thin part, 506 ... Projection part, 507 ... Relief groove, 508 ... Relief groove, 509 ... Extension line of rotor inner surface.

Claims (4)

A hollow for mounting the shaft;
A protrusion protruding in the direction of the rotation center from the inner peripheral surface of the hollow portion;
A VR resolver rotor, comprising: a groove formed at a base portion of the protruding portion and not recessed in a direction away from a rotation center but recessed in a direction inside the protruding portion. The rotor has a relatively thick wall portion and a relatively thin wall portion as viewed from the axial direction,
The rotor of a VR type resolver according to claim 1, wherein the protrusion is provided at a position avoiding the thick portion.   The rotor of a VR resolver according to claim 2, wherein the protrusion is provided on the thin portion.   A VR resolver using the rotor according to any one of claims 1 to 3.

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