JP5814445B1 - Resolver - Google Patents

Abstract

A resolver is provided in which non-uniform deformation in a circumferential direction of a resolver rotor outer detection surface is suppressed. A resolver rotor having a plurality of salient pole portions on the outer periphery and a shaft fixing hole that is press-fitted and fixed to a rotating shaft at a central portion, and a resolver rotor formed of a laminated steel plate and concentrically surrounding the resolver rotor. In the resolver that detects the rotation angle of the rotation shaft by a change in gap permeance between the resolver rotor and the resolver stator, the resolver rotor is provided with a laminated steel plate for each salient pole part. A laminated caulking portion is provided, and on the inner peripheral surface of the shaft fixing hole, a convex portion that is plastically deformed when the resolver rotor is press-fitted is provided corresponding to the laminated caulking portion, and the corresponding convex portion and the laminated caulking portion are provided. It is arranged on the same diameter line of the shaft fixing hole. [Selection] Figure 2

Description

  The present invention relates to a resolver that has a resolver rotor that is press-fitted into a rotation shaft and detects a rotation angle of a rotor.

In the conventional motor, the rotating shaft is rotatably held by a front bearing provided in the motor housing and a rear bearing provided at the rear end of the frame.
A magnet for generating a magnetic field is attached to the rear bearing side of the rotating shaft, and a rotor is configured. A resolver rotor of a resolver that detects the rotation angle of the rotor is attached to the counter-rotor side of the rotation shaft. A resolver stator that fixes a gap permeance with the resolver rotor in cooperation with the resolver rotor is fixed to the outer periphery of the resolver rotor. (For example, see Patent Documents 1 and 2)

Japanese Patent No. 5002859 Japanese Patent No. 4926205

  In the conventional resolver disclosed in Patent Literature 1, a positioning recess that opens to the hole is provided in the circumferential central portion of the predetermined protrusion except at least one in the rotation shaft fixing hole of the resolver rotor. Therefore, when the resolver rotor is press-fitted into the rotating shaft, there is a concern that a difference may occur in the amount of strain that appears on the outer detection surface of each salient pole portion depending on the presence or absence of the positioning recess. In addition, with respect to the positioning recess provided in the central portion in the circumferential direction of the salient pole portion, the salient pole portions on the both sides in the circumferential direction from the angular position where the press-fitting projection portion of the inner peripheral edge portion of the shaft fixing hole coincides with the valley portion between the salient pole portions. Accordingly, the reaction force of the pressure contact force from the rotating shaft is caused to act substantially evenly in the circumferential direction through each press-fitting convex portion.

  When the resolver rotor is press-fitted and fixed to the rotating shaft, the radial thickness of the resolver rotor is rapidly reduced in the positioning recess, and the recess is open on the inner diameter surface side, so that the rigidity is lowered. This corrects the amount of distortion at the salient pole apex as a countermeasure, and suppresses uneven deformation in the circumferential direction of the outer detection surface of the resolver rotor, but there is a limit to suppressing the deformation amount itself, and rotational symmetry Because it is not a shape, there is a limit to suppressing uneven deformation in the circumferential direction of the outer detection surface, and in the rotation angle signal generated by the resolver stator, the order component of the gap permeance error that causes the waveform distortion is promoted and detected. May affect accuracy.

In the conventional resolver disclosed in Patent Document 2, a plurality of convex portions that are plastically deformed when pressed into the rotating shaft are provided on the inner peripheral surface of the resolver rotor, and the convex portions are cut along the circumferential direction. The shape of the hole is an arc shape, and the radial width dimension is the largest in the hole portion formed facing the resolver rotor, and the radial width dimension of the hole portion and the resolver rotor is the smallest. In the part, the distance between the adjacent convex parts is set larger than that in the other part.
This invention solves the problems of Patent Document 1, and the amount of deformation is disclosed by locally plastically deforming the convex portion formed on the inner peripheral surface at the time of press-fitting and fixing the rotating shaft disclosed in Patent Document 2. The purpose is to further improve the suppression effect.

  A resolver according to the present invention includes a resolver rotor formed of a laminated steel plate having a plurality of salient pole portions on an outer periphery and a shaft fixing hole that is press-fitted and fixed to a rotating shaft at a central portion, and a resolver rotor concentric with the resolver rotor. A resolver stator that surrounds the resolver rotor, and detects a rotation angle of the rotating shaft by a change in gap permeance between the resolver rotor and the resolver stator. A laminated caulking portion that caulks the laminated steel sheet for each pole portion is provided, and a convex portion that is plastically deformed when the resolver rotor is press-fitted is provided on the inner peripheral surface of the shaft fixing hole, corresponding to the laminated caulking portion, In the resolver for detecting a pre-rotation angle, the corresponding convex portion and the laminated caulking portion are connected to the resolver rotor by the salient pole portion. A laminated caulking portion for caulking the laminated steel plate is provided on the inner peripheral surface of the shaft fixing hole, and a convex portion that is plastically deformed when the resolver rotor is press-fitted is provided corresponding to the laminated caulking portion. The convex portion and the laminated caulking portion are arranged on the same diameter line of the shaft fixing hole.

  According to the resolver according to the present invention, when the press-fitting to the rotating shaft is locally plastically deformed, the installation position of the convex part which becomes the axial press-fitting part of the resolver rotor and the installation position of the laminated caulking part of the steel plate are fixed to the shaft fixing hole. By reducing the amount of deformation that appears on the outer peripheral surface of the resolver rotor without reducing the slippage between the steel plates by reducing the slip between the steel plates, and by the convex portion arranged on the same diameter line of the shaft fixing hole The distortion on the outer peripheral surface of the resolver rotor is absorbed by the convex portion during press-fitting into the rotating shaft, so the deformation of the outer peripheral surface of the resolver rotor can be further suppressed, and the detection accuracy of the rotation angle is improved by the effect of suppressing the deformation. Can be made.

It is sectional drawing which shows the brushless motor in Embodiment 1 or Embodiment 2 of this invention. It is a front view which shows the resolver rotor of the resolver in Embodiment 1 of this invention. It is a front view which shows the resolver rotor of the resolver in Embodiment 2 of this invention. FIG. 4 is a right side view of the resolver rotor shown in FIG. 2 or FIG. 3. It is a front view which shows the resolver main-body part in the brushless motor shown in FIG. It is a right view of the resolver main-body part shown in FIG.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
In addition, the same code | symbol shows the same or an equivalent part between each figure.
In the following embodiments, a brushless motor (hereinafter abbreviated as “motor”) employing the resolver of the present invention will be described.

Embodiment 1 FIG.
The motor according to the first embodiment will be described with reference to FIGS. 1, 2, and 4 to 6.
In FIG. 1, a motor 1 is a motor incorporated in an electric power steering device, and includes a bottomed cylindrical frame 2 obtained by drawing an iron plate and a housing 3 made of aluminum fixed so as to cover the opening of the frame 2. And have.
A front bearing 5 having an outer ring portion caulked and fixed thereto is attached to the window portion 4 formed at the center of the housing 3.

A concave bearing box 6 is provided at the bottom of the frame 2, and a rear bearing 7 is inserted into the bearing box 6.
The front bearing 5 and the rear bearing 7 rotatably support a rotating shaft 8 made of iron, which is a magnetic material.
A magnet 9 that generates a magnetic field is attached to one end of the rotating shaft 8 to form a rotor 10. A protective tube (not shown) that protects the magnet 9 is put on the outer peripheral surface of the magnet 9.

A stator 11 is attached to the inner peripheral surface of the frame 2 so as to surround the outer periphery of the rotor 10.
The stator 11 has a stator core 12 formed by laminating silicon steel plates, a resin insulator 13, and a motor coil 14 wound around the insulator 13. Each of the motor coils 14 is Y- or Δ-connected, and a three-phase (U-phase, V-phase, W-phase) driving power is supplied to the motor coil 14 to generate a rotating magnetic field.
A connecting portion 8 a connected to an external mechanism is formed at the other end of the rotating shaft 8 on the housing side.

The resolver 18 for detecting the rotation angle of the rotating shaft 8 is formed by laminating silicon steel plates and rotating with the rotating shaft 8, and a resolver stator provided concentrically with the resolver rotor 15 and surrounding the resolver rotor 15. 20.
The resolver 18 detects the rotation angle of the rotary shaft 8 in cooperation with the resolver rotor 15 and the resolver stator 20 by a change in gap permeance therebetween.
The resolver rotor 15 has a plurality of salient pole portions 15 f projecting radially outward on the outer periphery, and a shaft fixing hole (rotation shaft press-fitting hole) 15 c that is press-fitted and fixed to the rotation shaft 8 at the center. The bush 16 is in contact with the front bearing 5 that is press-fitted and fixed to the bushing 17 that is press-fitted to the connecting portion 8 a side of the rotary shaft 8.

Further, the resolver rotor 15 is provided with a laminated caulking portion 15e for caulking laminated steel plates and a positioning hole 15d for assembling for each salient pole portion 15f on the same concentric circle as the shaft fixing hole 15c. Have the same configuration.
Further, on the inner peripheral surface 15 cc of the resolver rotor 15, five convex portions 15 a that are plastically deformed when the resolver rotor 15 is press-fitted and become axial press-fitting portions are formed corresponding to the laminated caulking portions 15 e (laminated layers). The same number of crimps and protrusions).
And the installation position of the corresponding lamination crimping part 15e and the installation position of the convex part 15a are arrange | positioned on the same radial line of the axis | shaft fixing hole 15c. That is, the laminated caulking portion 15e and the convex portion 15a are disposed on the same radial line at the same angle with the axis center of the shaft fixing hole 15c as the center at the end face of the resolver rotor 15.
Further, the laminated caulking portion 15e, the convex portion 15a, and the positioning hole 15d, which are arranged for each salient pole portion 15f, are arranged in a rotationally symmetrical shape.

According to the resolver having the above-described configuration, the convex portion 15 a that is locally plastically deformed when press-fitted into the rotary shaft 8 is formed on the inner peripheral surface 15 cc of the resolver rotor 15. Since the distortion of the rotor outer circumferential surface 15b is absorbed by the convex portion 15a, there is an effect of further suppressing the deformation of the resolver rotor outer circumferential surface 15b. Can be stabilized.
Further, the installation position of the laminated caulking portion 15e of the resolver rotor 15 that joins the silicon steel plates having high rigidity and the installation position of the convex portion 15a that serves as the axial press-fitting portion of the resolver rotor 15 are the same radius of the shaft fixing hole 15c. Since it is arranged on a line and configured in a rotationally symmetric shape, and the force generated at the time of press-fitting into the rotating shaft 8 is received by the lamination caulking portion 15e, the displacement that occurs between the laminations is reduced, and the deformation that appears on the resolver rotor outer peripheral surface 15b Is suppressed.
In addition, since five convex portions 15a that are plastically deformed are formed on the inner peripheral surface 15cc of the resolver rotor 15, only the convex portions 15a are locally localized when the resolver rotor 15 is press-fitted into the rotary shaft 8. The amount of deformation that plastically deforms and appears on the resolver rotor outer peripheral surface 15b can be suppressed, and the deformation of the resolver rotor outer peripheral surface 15b can be further suppressed.

In addition, by arranging the laminated caulking portion 15e of the silicon steel plate and the positioning hole 15d at the time of assembly on the same concentric circle as the shaft fixing hole 15c, there is a margin in the radial width dimension, and the resolver 18 can be downsized. Or, even a resolver rotor (rotating shaft having a large press-fit portion diameter) in the case of a motor with higher output can be manufactured by changing only the die of the rotating shaft press-fit portion (shaft fixing hole 15c) with the same press die. Since the shape of the resolver rotor outer peripheral surface 15b is not changed, the same resolver body 18A can be shared.
Thus, if the shape of the resolver rotor outer peripheral surface 15b is made the same, it can be manufactured by changing only the shaft press-fitting part mold with the same mold, and the resolver body 18A can also be shared.

5 and 6, a resolver body 18A having a resolver stator 20 is attached to the outer periphery of the resolver rotor 15, and the resolver body 18A has a male terminal 21 for signal line connection of the resolver body 18A. ing.
The resolver stator 20 is attached to a resolver stator mounting portion 19 provided in the housing 3, and includes a laminate 23 having a plurality of teeth 22 formed by laminating silicon steel plates and spaced at equal intervals in the circumferential direction, and an insulator. A one-phase excitation winding 25 and a two-phase output winding 26 are wound around the tooth 22 via 24. The laminated body 23 has the ear | edge part 40 which protruded on both sides, and the resolver main body 18A is being fixed to the housing 3 using the screw | thread (not shown) by this ear | edge part 40. FIG.
Here, the shape of the resolver rotor outer peripheral surface 5b is formed so as to periodically change the gap permeance with the resolver stator 20 in cooperation with the resolver stator 20, and the resolver rotor 15 and the resolver main body 18A. Thus, a resolver that outputs a signal according to the rotation angle of the rotor 10 is configured.

  The one-phase excitation winding 25 is continuously wound around each adjacent tooth 22. Of the two-phase output windings 26, the first output winding 26 a is wound continuously around each adjacent tooth 22 and radially outside the excitation winding 25 with respect to the center line of the tooth 22. Has been. The second output winding 26 b is wound around each adjacent tooth 22 continuously and on the radially outer side of the first output winding 26 a with respect to the center line of the tooth 22.

  A motor lead wire 27 connected to the motor coil 14 and supplying electric power is introduced from the outside through a grommet 30 as shown in FIG. A sensor lead wire (not shown) connected to the male terminal 21 via the female connector 28 and transmitting a signal related to the rotation angle of the rotor 10 to the outside is a grommet (not shown) provided in the housing 3. )) To the outside.

Next, the operation of the motor 1 having the above configuration will be described.
A 10 kHz, 5 Vpp sinusoidal excitation voltage is applied to the excitation winding 25 from a detection power source (not shown). When an excitation voltage is applied to the excitation winding 25, an excitation current flows through the excitation winding 25, and a magnetic flux is generated in a gap portion between the resolver rotor 15 and the resolver stator 20.
Further, power is supplied from the motor lead wire 27 to the motor coil 14, and a three-phase AC voltage is applied to the motor coil 14. When a three-phase AC voltage is applied to the motor coil 14, a rotating magnetic field is generated in the motor coil 14, and the rotor 10 rotates.

As the rotor 10 rotates, the resolver rotor 15 connected to each other via the rotating shaft 8 rotates, and the gap permeance between the resolver rotor 15 and the resolver stator 20 changes. Due to the change in the gap permeance, a phase difference occurs between the output voltage waveforms of the first output winding 26a and the second output winding 26b, so that the rotation angle can be detected.
The output voltages of the first output winding 26a and the second output winding 26b are transmitted via a sensor lead wire and input to a calculation unit (not shown), and the rotation angle of the rotor 10 is detected.

Embodiment 2. FIG.
The configuration other than the resolver rotor is the same as that of the first embodiment.
As shown in FIGS. 3 and 4, the resolver rotor 15 according to the second embodiment is mounted on the same concentric circle as the shaft fixing hole 15c between the two laminated caulking portions 15e and the two laminated caulking portions 15e. Positioning holes 15d for positioning are arranged for each of a plurality of salient pole portions 15f protruding outward in the radial direction, and have the same configuration.
The inner circumferential surface 15cc of the resolver rotor 15 is provided with ten convex portions 15a serving as rotary shaft press-fitting portions, and the installation position of the corresponding laminated caulking portion 15e and the installation position of the convex portion 15a are: It arrange | positions on the same radius line of the shaft fixing hole 15c. That is, the laminated caulking portion 15e and the convex portion 15a are disposed on the same radial line at the same angle with the axis center of the shaft fixing hole 15c as the center at the end face of the resolver rotor 15.
Further, the laminated caulking portion 15e, the convex portion 15a, and the positioning hole 15d, which are arranged for each salient pole portion 15f, are arranged in a rotationally symmetrical shape.
With this configuration, the force generated at the time of press-fitting into the rotating shaft 8 is received by the lamination caulking portion 15e, so that the displacement generated between the laminations is reduced, and the deformation appearing on the resolver rotor outer peripheral surface 15b is suppressed.
In the second embodiment, the laminated caulking portions 15e are configured on both sides with respect to the positioning hole 15d positioned at the center of the salient pole portion 15f in the outer diameter portion of the resolver rotor 15. As compared with the resolver rotor 15, the rigidity can be further improved.

Hereinafter, other configurations of the resolver in the first and second embodiments will be described.
The laminated steel plates of the resolver rotor 15 are rotationally laminated while being shifted by an angle between the salient pole portions 15f adjacent to each other. By configuring the resolver rotor 15 by rotational lamination in this manner, even when a deviation occurs in the plate thickness due to the slit position of the material, the lamination thickness is averaged, and the overall distortion deviation when the rotary shaft is press-fitted can be suppressed. . In addition, since the positioning hole 15d is provided for each salient pole portion by using the shape to be rotated, the rotational positioning at the time of assembly is possible with a small rotational angle, and the workability is improved.
Further, each of the plurality of salient pole portions 15f of the resolver rotor 15 includes a laminated caulking portion 15e, a positioning hole 15d, and a convex portion 15a serving as a press-fitting portion, and these portions have a rotationally symmetrical shape. By comprising, the whole distortion deviation is suppressed more.

The material hardness of the resolver rotor 15 is set to be lower than that of the rotating shaft 8.
With this configuration, the material hardness of the rotating shaft 8 is higher than that of the resolver rotor 15 (there is a difference in hardness between the rotating shaft and the resolver rotor), so that only the convex portion 15a of the resolver rotor is plastically deformed during press-fitting. Since only the convex portion 15a is locally deformed, it is possible to deform the plurality of salient pole portions 15f projecting radially outward of the resolver rotor by suppressing galling with the rotating shaft 8. That is, deformation of the resolver rotor outer peripheral surface 15b can be suppressed.

  The resolver 18 in the first embodiment and the second embodiment can be mounted on the brushless motor by press-fitting the resolver rotor 15 to the rotating shaft end portion of the brushless motor incorporated in the electric power steering apparatus. In this case, an electric power steering apparatus with stable rotation angle detection accuracy and stable transformation ratio can be obtained without increasing the number of parts and the number of assembly steps.

In the first and second embodiments, the case where the rotating electrical machine is the three-phase brushless motor 1 has been described as an example. However, the present invention is not limited to this example, and a DC motor or an AC motor may be used. It can be used for various motors and can produce the same effect. Further, the rotating electrical machine is not limited to a motor, and may be a generator.
In the present invention, each embodiment can be appropriately modified or omitted within the scope of the invention.

1: Motor (rotary electric machine), 5: Front bearing, 7: Rear bearing,
8: Rotating shaft, 8a: Connection part with external mechanism, 10: Rotor, 11: Stator,
15: Resolver rotor, 15a: Convex part (rotating shaft press-fitting part),
15b: resolver rotor outer peripheral surface, 15c: shaft fixing hole,
15 cc: inner peripheral surface (shaft fixing hole) of the resolver rotor 15,
15d: Positioning hole, 15e: Laminated caulking portion of the resolver rotor 15,
15f: salient pole part of resolver rotor 15, 18: resolver,
18A: resolver main body, 19: resolver stator mounting portion,
20: Resolver stator, 25: Excitation winding, 26: Output winding,
26a: first output winding, 26b: second output winding.

Claims (5)

A resolver rotor having a plurality of salient pole portions on the outer periphery and a shaft fixing hole that is press-fitted and fixed to the rotary shaft at the center portion, and a resolver provided concentrically with the resolver rotor and surrounding the resolver rotor A resolver configured to detect a rotation angle of the rotation shaft by a change in gap permeance between the resolver rotor and the resolver stator;
The resolver rotor is provided with a laminated caulking portion that caulks the laminated steel plate for each salient pole portion, and a convex portion that is plastically deformed when the resolver rotor is press-fitted on the inner peripheral surface of the shaft fixing hole. A resolver, wherein the resolver is provided corresponding to a caulking part, and the corresponding convex part and the laminated caulking part are arranged on the same diameter line of the shaft fixing hole. In the resolver rotor, a positioning hole and a pair of laminated caulking portions positioned on both sides of the positioning hole are arranged on a circumference concentric with the shaft fixing hole, and an inner periphery of the shaft fixing hole is provided. The surface is provided with the same number of convex portions as the laminated caulking portions, and the convex portions provided for each of the salient pole portions, the positioning holes, and the laminated caulking portions are arranged rotationally symmetrically. The resolver according to claim 1.   The resolver according to claim 1 or 2, wherein the laminated steel plates are rotationally laminated while being shifted by an angle between the salient pole portions adjacent to each other.   4. The resolver according to claim 1, wherein a material hardness of the resolver rotor is lower than that of the rotation shaft. 5. The resolver according to any one of claims 1 to 4, wherein the resolver rotor is press-fitted and fixed to a rotating shaft of a brushless motor incorporated in an electric power steering apparatus.