JP2023014775A - motor unit - Google Patents

Abstract

To provide a motor unit having a resolver that has an increased accuracy in detecting a rotation angle.SOLUTION: A retainer 40 has a circular ring flange part 41 that is in contact with an end face of a resolver rotor 11 from the tip of a rotation shaft 23, a press-fit part 42 that is extended in the axial direction from an inner peripheral portion of the flange part 41 and externally fitted to the rotation shaft 23, and a plurality of pawl parts 43 that are provided on the flange part 41 or the press-fit part 42, brought into contact in the axial direction with an enlarged diameter part 241 of the rotation shaft 23 to spread in an outer peripheral side, and in contact from the inside with an insertion hole of the resolver rotor 11.SELECTED DRAWING: Figure 2

Description

The present invention relates to a motor unit having a resolver.

A resolver is used to detect the rotation of a rotating electric machine (motor). The resolver detects the rotation angle of the motor's rotation shaft by detecting changes in the reluctance of the resolver rotor, which is fixed to the rotation shaft of the motor and rotates coaxially, as changes in the current signal by the resolver stator arranged around it. do.

In motor control, there is a demand to detect the rotation angle of the motor with higher accuracy. For this reason, it is necessary to attach the resolver rotor to the rotating shaft with high accuracy. Conventionally, in a resolver rotor, it has been common to press-fit and fix a rotating shaft into a press-fitting hole formed in the axial center of the resolver rotor. In such a structure in which the resolver rotor itself is externally fitted, the resolver rotor deforms outward due to the stress received during press-fitting, so there is a problem that the change in reluctance due to rotation is not uniform and the detection accuracy is lowered. .

In Patent Document 1, a plurality of grooves are provided inside the hole of the resolver rotor so that when the rotating shaft is press-fitted into the press-fitting hole, the amount of distortion to the outer circumference of the resolver rotor is equal on all outer circumferences. , disclose a resolver rotor configured to restrain deformation of the resolver rotor.

JP 2008-275385 A

The prior art is configured to uniformly deform the resolver rotor at the time of press-fitting to reduce strain in the circumferential direction. However, even with such a configuration, deformation in the radial direction of the resolver rotor cannot be avoided, and there is a limit to improving the detection accuracy.

SUMMARY OF THE INVENTION The present invention has been made in view of such problems, and it is an object of the present invention to provide a motor unit having a resolver that suppresses deformation when the resolver rotor is fixed to a rotating shaft, thereby improving the detection accuracy of the rotation angle. aim.

An aspect of the present invention is applied to a motor unit having a motor and a resolver that detects the rotation angle of the rotation shaft of the motor. The resolver includes a resolver rotor, and a retainer interposed between the rotating shaft and the resolver rotor to fix the resolver rotor to the rotating shaft. The resolver rotor has an insertion hole through which the rotating shaft is inserted while being spaced apart from the rotating shaft. The tip of the rotating shaft is formed as a small diameter portion smaller in diameter than the body portion other than the tip portion, and has an enlarged diameter portion at the boundary between the small diameter portion and the body portion. The retainer includes an annular flange portion that abuts on the end face of the resolver rotor from the tip side of the rotating shaft, a press-fitting portion that extends axially from an inner peripheral portion of the flange portion and is fitted onto the rotating shaft, and the flange portion. Alternatively, it has a plurality of claw portions provided in the press-fitting portion, which expands toward the outer peripheral side by contacting the enlarged diameter portion of the rotating shaft in the axial direction, and contacts the insertion hole of the resolver rotor from the inside.

According to the present invention, the resolver rotor is fixed to the retainer by the claw portion of the retainer interposed between the resolver rotor and the rotating shaft, and the retainer is press-fitted and fixed to the rotating shaft, so that the resolver rotor itself rotates directly. Deformation caused by being press-fitted onto the shaft is suppressed. This improves the detection accuracy of the rotation angle.

FIG. 1 is a schematic diagram of a motor unit according to an embodiment of the invention. FIG. 2 is an exploded perspective view of the motor unit centered on the rotating shaft. FIG. 3 is a schematic diagram of a modified motor unit. FIG. 4 is a partial cross-sectional view of a resolver rotor of a modification. FIG. 5 is an exploded perspective view of the motor unit centering on the rotation shaft of the modification.

Embodiments of the present invention will be described below with reference to the accompanying drawings.

FIG. 1 is a schematic diagram of the motor unit 1 of this embodiment, showing a front view and a cross-sectional view of the rotating shaft 23 .

The motor unit 1 is composed of a motor 20 and a resolver 10 fixed to a rotating shaft 23 of the motor 20 .

The motor 20 includes an annular stator 21 , a rotor 22 rotatably supported on the inner periphery of the stator 21 , and a rotary shaft 23 coaxially rotating with the rotor 22 . The motor 20 receives power from a battery (not shown) and rotates the rotor 22 .

The motor 20 of this embodiment is mounted, for example, on an electric vehicle and functions as an electric motor that drives the wheels. In addition, the motor 20 also functions as a generator that generates (regenerates) power by receiving the driving force generated by the rotation of the wheels. Note that the motor 20 may be used as a driving device for devices other than automobiles, such as various electric devices or industrial machines.

A resolver 10 that detects the rotation angle of the rotating shaft 23 is provided near one end of the rotating shaft 23 of the motor 20 .

The resolver 10 is composed of a resolver rotor 11, a resolver stator 12, and a retainer 40, which will be described later.

The resolver rotor 11 is a cylindrical member that is fixed to the rotating shaft 23 and rotates together with the rotating shaft 23 . The resolver rotor 11 is constructed by stacking magnetic steel plates hollowed out in a predetermined shape in the axial direction. The resolver rotor 11 has a magnetic pole portion 11a configured such that a portion of its outer shape protrudes radially outward. The magnetic pole portions 11a are formed at predetermined intervals (four locations in this embodiment) in the circumferential direction.

The resolver stator 12 is an annular member provided outside the resolver rotor 11 . The resolver stator 12 outputs an electrical signal as the resolver rotor 11 rotates. More specifically, when the resolver rotor 11 rotates, the clearance between the outer circumference of the resolver rotor 11 and the inner circumference of the resolver stator 12 changes. The resolver stator 12 outputs as an electric signal the change in reluctance caused by the change in the clearance. A controller (not shown) acquires the output electrical signal. The controller calculates a signal indicating the rotation angle of the rotating shaft 23 by a predetermined calculation. The calculated rotation angle is used for drive control of the motor 20 .

In this manner, the controller controls the drive torque of the motor 20 using the rotation angle detected by the resolver 10 .

Next, a mounting structure for mounting the resolver rotor 11 on the rotating shaft 23 will be described.

In order to detect the rotation angle of the motor 20 with high accuracy, it is necessary to attach the resolver rotor 11 to the rotating shaft 23 of the motor 20 with high accuracy. Conventionally, a resolver rotor is generally fixed to a rotating shaft by press-fitting the rotating shaft of a motor into an insertion hole formed in the center of the resolver rotor.

However, when the resolver rotor is directly press-fitted onto the rotating shaft, the insertion hole is enlarged by the stress received by the press-fitting, and the external shape of the resolver rotor is deformed so as to expand radially outward. When the outer shape of the resolver rotor is deformed, the clearance between the resolver rotor and the resolver stator changes, and the generated reluctance fluctuates.

Therefore, in the present embodiment, as described below, the resolver rotor 11 is configured to be attached to the rotary shaft 23 with high accuracy without deformation.

FIG. 2 is an exploded perspective view of the motor unit 1 centering on the rotating shaft 23 of this embodiment.

The resolver rotor 11 is attached to the rotary shaft 23 so as to be non-rotatable relative to the rotary shaft 23 by engaging the claws 43 protruding from the retainer 40 press-fitted to the rotary shaft 23 with the grooves 50 formed in the resolver rotor 11 . be done.

The rotating shaft 23 is composed of a body portion 230 and a small diameter portion 231 protruding from the tip thereof. A boundary portion between the small-diameter portion 231 and the body portion 230 has an enlarged-diameter portion 241 having a diameter slightly larger than that of the small-diameter portion 231 and formed in a stepped shape. Further, between the enlarged diameter portion 241 and the main body portion 230, there is a receiving portion 242 which is formed flat due to the step.

The retainer 40 includes an annular flange portion 41 , a cylindrical press-fitting portion 42 formed on the inner peripheral side of the flange portion, and a plurality of claw portions 43 projecting radially outward from the press-fitting portion 42 . Configured.

The flange portion 41 has an annular shape extending radially outward on the axial end portion side of the retainer 40 . The flange portion 41 abuts on the surface of the resolver rotor 11 on the axial end side.

The press-fit portion 42 is a cylindrical portion extending from the inner periphery of the flange portion 41 , and the inner peripheral surface thereof is fitted onto the small diameter portion 231 of the rotating shaft 23 .

The claw portion 43 is formed at the motor 20 side end portion of the press-fitting portion 42 . The claw portions 43 are arranged at predetermined intervals in the circumferential direction of the press-fitting portion 42 and are formed to protrude radially outward. As shown in FIG. 2, the retainer 40 has four claw portions 43 at intervals of 90 degrees in the circumferential direction.

The tip of the claw portion 43 is formed in a tapered shape so that the width of the claw portion 43 decreases toward the outside in the radial direction.

The resolver rotor 11 has an insertion hole 111 at its center through which the small-diameter portion 231 of the rotating shaft 23 is inserted. The insertion hole 111 has a diameter larger than that of the small-diameter portion 231 and the enlarged-diameter portion 241 , so that the small-diameter portion 231 does not interfere with the inner periphery of the insertion hole 111 .

The insertion hole 111 is provided with a plurality of grooves 50 having a concave shape extending radially outward from the inner periphery thereof. The groove portion 50 extends in the axial direction so that the claw portion 43 of the retainer 40 can pass therethrough in the axial direction. Four groove portions 50 are formed at equal intervals in the circumferential direction of the insertion hole 111 . The groove portion 50 is arranged at a position where a line connecting the outermost periphery of the magnetic pole portion 11 a of the resolver rotor 11 and the center of the resolver rotor 11 intersects the inner wall of the insertion hole 111 .

As will be described later, the groove portion 50 has a groove depth such that the claw portion 43 can pass through in the axial direction in the non-fixed state, and the tip of the claw portion 43 engages with the inner peripheral portion of the groove portion 50 in the fixed state. It is formed Furthermore, the groove portion 50 is formed in a tapered shape in the depth direction (radial direction) of the groove similarly to the claw portion 43 .

Since the magnetic pole portion 11a of the resolver rotor 11 protrudes radially outward of the resolver rotor 11, the distance (thickness) from the insertion hole 111 to the outer circumference of the resolver rotor 11 is large in the magnetic pole portion 11a. Therefore, even if the groove portion 50 is arranged on the inner periphery of the insertion hole 111, the mechanical strength of the resolver rotor 11 is not impaired.

Next, a method for fixing the resolver rotor 11 to the rotating shaft 23 will be described.

First, the retainer 40 is inserted into the insertion hole 111 of the resolver rotor 11, and the resolver rotor 11 and the retainer 40 are combined together. The retainer 40 is axially inserted into the insertion hole 111 with the claws 43 of the retainer 40 aligned with the grooves 50 formed in the insertion hole 111 of the resolver rotor 11. It is moved to a position where it contacts the end surface 11b of the rotor 11 . At this point, the tip of the claw portion 43 is not in contact with the inner peripheral surface of the insertion hole 111 , that is, the inner wall of the groove portion 50 .

Next, the integrally combined resolver rotor 11 and retainer 40 are axially inserted from the tip of the rotating shaft 23 . As a result, the press-fit portion 42 of the retainer 40 is fitted onto the small-diameter portion 231 of the rotating shaft 23 . The resolver rotor 11 is inserted until the end face on the motor 20 side hits the receiving portion 242 of the rotary shaft 23 . After the insertion, the resolver rotor 11 abuts against the receiving portion 242, whereby the resolver rotor 11 is axially positioned.

Before or substantially at the same time that the resolver rotor 11 abuts against the receiving portion 242 , the inner peripheral side of the claw portion 43 of the retainer 40 contacts the enlarged diameter portion 241 of the rotating shaft 23 . Since the diameter of the enlarged diameter portion 241 is larger than that of the small diameter portion 231, the claw portion 43 deforms so as to expand radially outward as shown in FIG.

By deforming the claw portion 43 radially outward, the tip of the claw portion 43 hits the groove portion 50 of the resolver rotor 11 and engages with the inner wall of the groove portion 50 . As a result, the resolver rotor 11 cannot move in the axial direction due to the four claw portions 43 of the retainer 40 .

At this time, since the tip portion of the claw portion 43 and the groove portion 50 are tapered in the depth direction, the tip thereof is guided by the tapered inner wall of the groove portion 50 as the claw portion 43 moves radially outward. , the resolver rotor 11 is positioned in the circumferential direction (rotational direction).

More specifically, since the tip of the claw portion 43 is tapered, force is evenly applied to both sides of the inner wall of the groove portion 50 as the claw portion 43 moves radially outward. is set at a position such that the center of the tip of the groove 50 coincides with the center of the groove 50 . Similarly, since the inner wall of the groove portion 50 is tapered, the claw portion 43 is set at a position where force is evenly applied to the inner wall as the claw portion 43 moves radially outward. Thereby, more precise positioning is achieved between the claw portion 43 and the groove portion 50 .

In this manner, the retainer 40 is press-fitted and fixed to the small-diameter portion 231 of the rotating shaft 23 at the press-fitting portion 42 , and the flange portion 41 and the claw portion 43 prevent the resolver rotor 11 from coming off. can be fixed to

Since only a part of the inner wall of the groove portion 50 of the resolver rotor 11 is engaged with the pawl portion 43, no stress is generated in the radial direction as compared with the case where the resolver rotor 11 is directly press-fitted into the rotating shaft 23. deformation is suppressed.

As described above, the motor unit 1 of this embodiment has the motor 20 and the resolver 10 that detects the rotation angle of the rotating shaft 23 of the motor 20 . The resolver 10 includes a resolver rotor 11 and a retainer 40 interposed between the rotating shaft 23 and the resolver rotor 11 to fix the resolver rotor 11 to the rotating shaft 23 . The resolver rotor 11 is provided with an insertion hole 111 through which the rotating shaft 23 is inserted while being spaced from the rotating shaft 23 . The tip of the rotary shaft 23 is formed as a small diameter portion 231 having a diameter smaller than that of the body portion 230 other than the tip. The retainer 40 includes an annular flange portion 41 that contacts the end face 11b of the resolver rotor 11 from the tip end side of the rotating shaft 23, and extends axially from the inner peripheral portion of the flange portion 41 and is fitted onto the rotating shaft 23. and a plurality of claw portions which are provided in the press-fit portion 42 and spread outwardly by contacting the enlarged diameter portion 241 of the rotating shaft 23 in the axial direction and contacting the insertion hole 111 of the resolver rotor 11 from the inside. 43 and .

With such a configuration, the resolver rotor 11 is fixed to the retainer 40 by the flange portion 41 and the claw portions 43 of the retainer 40, and the retainer 40 is press-fitted to the rotating shaft 23, so that the resolver rotor 11 itself can be directly It is not press-fitted onto the rotating shaft 23 . According to such a fixing structure, deformation caused by press-fitting is suppressed, and the detection accuracy of the rotation angle of the resolver 10 can be improved.

Furthermore, since press-fitting and fixing the retainer 40 to the rotary shaft 23 and fixing the retainer 40 and the resolver rotor can be performed in one step, the manufacturing man-hours can be reduced, and the manufacturing cost of the motor 20 can be suppressed. can be done.

Further, in the present embodiment, the press-fit portion 42 is formed as a cylindrical portion protruding from the inner peripheral portion of the flange portion 41 in the axial direction. A plurality of claw portions 43 are provided at predetermined intervals in the circumferential direction of the cylindrical portion, and are formed by extending radially outward from the end surface of the cylindrical portion.

With such a configuration, the plurality of claw portions 43 provided at predetermined intervals in the circumferential direction come into contact with the inner wall of the insertion hole 111 of the resolver rotor 11 , so that the resolver rotor 11 is more securely attached to the rotating shaft 23 . can be fixed.

Further, in this embodiment, the insertion hole 111 of the resolver rotor 11 has a plurality of grooves 50 formed in a concave shape outward from the inner wall in the circumferential direction.

With such a configuration, the claw portion 43 is engaged with the groove portion 50 of the resolver rotor 11, so that the rotational direction position of the resolver rotor 11 can be easily set.

Further, in this embodiment, the tip of the claw portion 43 is tapered radially outward, and the groove portion 50 is tapered radially outward.

With such a configuration, the claw portion 43 abuts against the enlarged diameter portion 241 and the tapered distal end moves radially outward to be guided by the inner wall of the groove portion 50 , so that the claw portion 43 is accurately positioned relative to the groove portion 50 . is positioned at

Further, since the groove portion 50 is formed in a tapered shape, the claw portion 43 abuts against the enlarged diameter portion 241 and the distal end thereof moves radially outward, being guided by the inner wall of the tapered groove portion 50, The claw portion 43 is accurately positioned with respect to the groove portion 50 .

Further, in this embodiment, the resolver rotor 11 has the magnetic pole portion 11a of which part of the outer shape protrudes radially outward, and the groove portion 50 is arranged radially inward of the magnetic pole portion 11a.

With such a configuration, the groove 50 is arranged at the position of the magnetic pole portion 11a having a large distance (thickness) to the outer circumference of the resolver rotor 11, so that the mechanical strength of the groove 50 of the resolver rotor 11 can be increased.

Next, a modified example of this embodiment will be described.

FIG. 3 is a schematic diagram of the motor unit 1 of a modified example of the present embodiment, showing a front view and a cross-sectional view of the rotating shaft 23. As shown in FIG. FIG. 4 shows a cross-sectional view taken along line IV-IV of FIG. FIG. 5 shows an exploded perspective view of the motor unit 1 centering on the rotating shaft 23. As shown in FIG.

As described above, in the resolver rotor 11 , the claws 43 projecting from the retainer 40 press-fitted and fixed to the rotating shaft 23 are engaged with the inner peripheral surface (groove 50 ) of the insertion hole 111 formed in the resolver rotor 11 . Thus, it is attached to the rotary shaft 23 so as not to rotate relative to it.

A retainer 40 of a modified example shown in FIG. 3 is formed such that a claw portion 43 and a press-fitting claw portion 44 configured as a press-fitting portion 42 project in the axial direction from the inner peripheral portion of a flange portion 41 as different portions. It was configured as follows.

The press-fit claw portion 44 is formed so as to protrude toward the motor 20 from the inner peripheral portion of the flange portion 41 while curving gently. A plurality of (four) press-fit claw portions 44 are provided at predetermined intervals (90 degrees) in the circumferential direction of the flange portion 41 . As shown in FIG. 4 , the press-fitting claw portion 44 is configured such that its inner peripheral surface is in contact with the outer diameter of the small-diameter portion 231 , and is fitted onto the outer periphery of the small-diameter portion 231 of the rotating shaft 23 to form a press-fitting claw. The portion 44 is press-fitted and fixed to the small diameter portion 231 . The axial length of the press-fit claw portion 44 from the flange portion 41 is set to a length that does not come into contact with the enlarged diameter portion 241 even when the retainer 40 is assembled to the rotating shaft 23 .

The claw portion 43 protrudes from the inner peripheral portion of the flange portion 41 while gently curving in the axial direction, and extends so as to curve radially outward along the way. The claw portion 43 is provided between press-fit claw portions 44 , 44 provided in the circumferential direction of the flange portion 41 . The inner peripheral surface of the claw portion 43 is configured so as not to contact the small diameter portion 231 but to contact the enlarged diameter portion 241 .

The retainer 40 is formed, for example, by pressing a flat metal plate. The retainer 40 is formed by one-time pressing by bending the claw portion 43 and the press-fitting claw portion 44 while hollowing out the annular flange portion 41, the claw portion 43, and the press-fitting claw portion 44 by press working. can be done.

A first groove portion 51 is formed in the insertion hole 111 of the resolver rotor 11 at a position facing the claw portion 43 of the retainer 40 . Four first grooves 51 are formed at equal intervals in the circumferential direction of the insertion hole 111 . The first groove portion 51 is arranged at a position where a line connecting the outermost periphery of the magnetic pole portion 11 a of the resolver rotor 11 and the center of the resolver rotor 11 intersects the insertion hole 111 . The first groove portion 51 allows the claw portion 43 to pass through in the axial direction in the non-fixed state, and the tip of the claw portion 43 engages with the inner peripheral portion of the first groove portion 51 in the fixed state. formed in depth.

A second groove portion 52 is formed in the resolver rotor 11 at a position facing the press-fit claw portion 44 of the retainer 40 . Four second groove portions 52 are formed at equal intervals in the circumferential direction of the insertion hole 111 . The second groove portion 52 is formed to have a groove depth that allows the press-fit claw portion 44 to pass therethrough in the axial direction.

Next, a method of fixing the resolver rotor 11 to the rotating shaft 23 of the modification shown in FIG. 3 will be described.

First, the retainer 40 is inserted into the insertion hole 111 of the resolver rotor 11, and the resolver rotor 11 and the retainer 40 are combined together. The position of the claw portion 43 of the retainer 40 is aligned with the position of the first groove portion 51 formed in the insertion hole 111 of the resolver rotor 11, and the position of the press-fit claw portion 44 of the retainer 40 is aligned with the position of the second groove portion 52. In this state, the retainer 40 is axially inserted into the insertion hole 111 and moved to a position where the flange portion 41 of the retainer 40 contacts the end surface 11 b of the resolver rotor 11 . At this point, the tip of the claw portion 43 is not in contact with the inner wall of the groove portion 50 .

Next, the integrally combined resolver rotor 11 and retainer 40 are axially inserted from the tip of the rotating shaft 23 . As a result, as shown in FIG. 4 , the inner peripheral surface of the press-fit claw portion 44 of the retainer 40 is fitted onto the small diameter portion 231 of the rotating shaft 23 . The resolver rotor 11 is inserted until the end face on the motor 20 side hits the receiving portion 242 of the rotary shaft 23 . The resolver rotor 11 abuts against the receiving portion 242 to position the resolver rotor 11 in the axial direction.

Before the resolver rotor 11 abuts against the receiving portion 242 or substantially at the same time, the inner peripheral surface of the claw portion 43 of the retainer 40 contacts the enlarged diameter portion 241 of the rotating shaft 23 as shown in FIG. Since the diameter of the enlarged diameter portion 241 is larger than that of the small diameter portion 231, the claw portion 43 deforms so as to expand radially outward.

By deforming the claw portion 43 radially outward, the tip of the claw portion 43 hits the first groove portion 51 of the resolver rotor 11 and engages with the inner wall of the first groove portion 51 . As a result, the resolver rotor 11 cannot move in the axial direction due to the claw portions 43 of the retainer 40 .

Thus, the motor unit 1 of the modified example of the present embodiment has the motor 20 and the resolver 10 that detects the rotation angle of the rotating shaft 23 of the motor 20 . The resolver 10 includes a resolver rotor 11 and a retainer 40 interposed between the rotating shaft 23 and the resolver rotor 11 to fix the resolver rotor 11 to the rotating shaft 23 . The resolver rotor 11 is provided with an insertion hole 111 through which the rotating shaft 23 is inserted while being spaced from the rotating shaft 23 . The tip of the rotary shaft 23 is formed as a small diameter portion 231 having a diameter smaller than that of the body portion 230 other than the tip. The retainer 40 includes an annular flange portion 41 that abuts on the end face 11b of the resolver rotor 11 from the tip side of the rotating shaft 23, and extends axially from the inner peripheral portion of the flange portion 41 and is fitted onto the rotating shaft 23. and a plurality of claw portions which are provided on the flange portion 41 and spread outwardly by contacting the enlarged diameter portion 241 of the rotating shaft 23 in the axial direction to contact the insertion hole 111 of the resolver rotor 11 from the inside. 43 and .

Even when the retainer 40 has such a shape, the retainer 40 is press-fitted and fixed to the small-diameter portion 231 of the rotating shaft 23 at the press-fit claw portion 44, and the flange portion 41 and the claw portion 43 prevent the resolver rotor 11 from coming off. This makes it possible to fix the resolver rotor 11 to the rotating shaft 23 .

Therefore, since only a part of the inner wall of the groove portion 50 is engaged with the pawl portion 43, the resolver rotor 11 is not subjected to stress in the radial direction as compared with the case where the rotating shaft 23 is directly press-fitted. Deformation of the shape is suppressed.

Further, the press-fit portion 42 of the modified example of the present embodiment is formed by a plurality of press-fit pawl portions 44 extending in the axial direction from the inner peripheral portion of the flange portion 41 and provided at predetermined intervals in the circumferential direction. , and the inner peripheral surface of the press-fit claw portion 44 is fitted to the rotating shaft 23 . On the other hand, the claw portions 43 are configured to extend radially outward from the inner peripheral side of the flange portion 41 and to be arranged in plurality between the press-fitting claw portions 44 .

With such a configuration, the claw portion 43 for fixing the resolver rotor 11 and the press-fitting claw portion 44 for press-fitting and fixing the rotating shaft 23 can share the functions, and the direction of the force applied to each can be separated. be able to. Thereby, the resolver rotor 11 can be fixed to the rotating shaft 23 with higher accuracy.

Furthermore, since the retainer 40 has a shape that can be formed by a single process of press-punching and bending a flat metal plate, the manufacturing cost of the retainer 40 can be suppressed.

Although the embodiments of the present invention have been described above, the above embodiments merely show a part of application examples of the present invention, and are not intended to limit the technical scope of the present invention to the specific configurations of the above embodiments. .

In the above-described embodiment, four claw portions 43 and four groove portions 50 (first groove portions 51) are arranged at intervals of 90 degrees in the circumferential direction. If possible, two or three, or five or more may be provided.

In the above-described embodiments, the enlarged diameter portion 241 may have any shape as long as the diameter thereof is larger than that of the small diameter portion 231 . For example, the diameter may be tapered from the small-diameter portion 231 to the main body portion 230 , or the boundary between the small-diameter portion 231 and the main body portion 230 may be curved in a fillet shape so that the diameter increases.

1: Motor unit, 10: Resolver, 11: Resolver rotor, 11a: Magnetic pole part, 12: Resolver stator, 20: Motor, 23: Rotating shaft, 40: Retainer, 41: Flange part, 42: Press fitting part, 43: Claw Part 44: Press-fit claw portion 50: Groove portion 51: First groove portion 52: Second groove portion 111: Insertion hole 230: Body portion 231: Small diameter portion 241: Expanded diameter portion 242: Receptacle stop

Claims (6)

A motor unit having a motor and a resolver that detects a rotation angle of a rotation shaft of the motor,
The resolver includes a resolver rotor, and a retainer interposed between the rotating shaft and the resolver rotor to fix the resolver rotor to the rotating shaft,
The resolver rotor has an insertion hole through which the rotating shaft is inserted with a gap between it and the rotating shaft,
The tip of the rotating shaft is formed as a small diameter portion smaller in diameter than the body portion other than the tip portion, and a boundary portion between the small diameter portion and the body portion has an enlarged diameter portion,
The retainer is
an annular flange portion that abuts on the end surface of the resolver rotor from the distal end side of the rotating shaft;
a press-fit portion extending axially from an inner peripheral portion of the flange portion and fitted onto the rotating shaft;
a plurality of claw portions provided on the flange portion or the press-fitting portion, spread outward by axial contact with the enlarged diameter portion of the rotating shaft, and contact the insertion hole of the resolver rotor from the inside; having
motor unit. The motor unit according to claim 1,
The press-fit portion is formed as a cylindrical portion axially protruding from an inner peripheral portion of the flange portion,
A plurality of the claw portions are provided at predetermined intervals in the circumferential direction of the cylindrical portion, and are provided by extending radially outward from the end surface of the cylindrical portion.
motor unit. The motor unit according to claim 1,
The press-fit portion extends in the axial direction from the inner peripheral portion of the flange portion and is formed by a plurality of press-fit claw portions provided at predetermined intervals in the circumferential direction. is externally fitted on the rotating shaft with
The claw portion extends radially outward from the inner peripheral side of the flange portion, and a plurality of the claw portions are arranged between the press-fitting claw portion and the press-fitting claw portion.
motor unit. The motor unit according to any one of claims 1 to 3,
The insertion hole of the resolver rotor includes a plurality of grooves formed in a concave shape outward from the inner wall in the circumferential direction,
The tip of the claw portion is positioned within the groove portion,
motor unit. The motor unit according to claim 4,
The claw portion is formed to taper radially outward, and the groove portion is formed to taper radially outward.
motor unit. The motor unit according to claim 4 or 5,
The resolver rotor has a magnetic pole portion, a part of the outer shape of which protrudes radially outward,
The groove portion is arranged radially inside the magnetic pole portion,
motor unit.

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