Rotation driving device

Patent metadata

Field	Value
Publication number	US-11624424-B2
Application number	US-202217578399-A
Country	US
Kind code	B2
Filing date	Jan 18, 2022
Priority date	Mar 31, 2021
Publication date	Apr 11, 2023
Grant date	Apr 11, 2023

Abstract

A rotation driving device includes: a body 10 , made of resin, and having an accommodation hole 13 in a cylindrical shape with an axis S as a center; a motor M, comprising a rotor 60 provided in an accommodation hole of the body and rotating around the axis and a rotation shaft 40 integrally rotating around the axis with the rotor and extending in an axial direction; a first bearing B 1 fixed to an end side of the body and a second bearing B 2 fixed to the other end side of the body in the axial direction, so as to rotatably support the rotation shaft; and a first cover member 110 connected to the one end side of the body and a second cover member 120 connected to the other end side of the body.

First claim

What is claimed is:

1. A rotation driving device, comprising:
a body, made of resin, and having an accommodation hole in a cylindrical shape with an axis as a center;
a motor, comprising a rotor provided in the accommodation hole of the body and rotating around the axis and a rotation shaft integrally rotating around the axis with the rotor and extending in an axial direction;
a first bearing fixed to one end side of the body and a second bearing fixed to the other end side of the body in the axial direction, so as to rotatably support the rotation shaft; and
a first cover member connected to the one end side of the body and a second cover member connected to the other end side of the body,
wherein the body comprises a first bearing holder embedded in the one end side and a second bearing holder pressed into the other end side, the first bearing is fit and fixed to the first bearing holder, and the second bearing is fit and fixed to the second bearing holder.

2. The rotation driving device as claimed in claim 1 , wherein the rotation shaft comprises a connection part outside the first bearing in the axial direction, and
the rotation driving device further comprises a deceleration unit provided between the first cover member and the body, and connected to the connection part to decelerate a speed of the rotation shaft.

3. The rotation driving device as claimed in claim 1 , wherein the first bearing holder comprises a first limiting part limiting a movement of the first bearing toward an outer side in the axial direction, and
the second bearing holder comprises a second limiting part limiting a movement of the second bearing toward the outer side in the axial direction.

4. The rotation driving device as claimed in claim 2 , further comprising:
a first washer, provided in adjacency with the first bearing to apply an urging force to the rotation shaft in the axial direction; and
a second washer, provided in adjacency with the output rotation body to apply an urging force to the output rotation body in the axial direction.

5. The rotation driving device as claimed in claim 2 , wherein the connection part is an eccentric shaft part rotating eccentrically around the axis, and
the deceleration unit comprises an external gear connected to the eccentric shaft part to rotate and revolve around the axis, an internal gear partially engaged with the external gear, and an output rotation body interlocked with the external gear to rotate around the axis.

6. The rotation driving device as claimed in claim 5 , wherein the internal gear is embedded and fixed to the one end side of the body.

7. The rotation driving device as claimed in claim 5 , wherein the external gear is rotatably supported by the eccentric shaft part via a third bearing.

8. The rotation driving device as claimed in claim 5 , wherein the output rotation body is supported to be rotatable around the axis with respect to the first cover member.

9. The rotation driving device as claimed in claim 8 , wherein the output rotation body is rotatably supported by the first cover member via a bush in a cylindrical shape.

10. The rotation driving device as claimed in claim 5 , wherein the external gear comprises a first disc part in which external teeth engaged with the internal gear and a first engagement part engaged with the output rotation body are formed and a first cylindrical part integrally formed with the first disc part,
the first disc part is provided in adjacency with a wall surface of the body on the one end side, and
the first cylindrical part is formed to protrude outward from the first disc part in the axial direction.

11. The rotation driving device as claimed in claim 10 , wherein the output rotation body comprises a second disc part which is provided in adjacency with the first disc part of the external gear in the axial direction and in which a second engagement part engaged with the first engagement part is formed, and a second cylindrical part integrally formed with the second disc part and provided to surround a periphery of the first cylindrical part.

12. The rotation driving device as claimed in claim 11 , wherein the first engagement part is a protrusion part protruding outward in the axial direction, and
the second engagement part is an insertion hole into which the protrusion part is movably inserted.

13. The rotation driving device as claimed in claim 11 , wherein the output rotation body comprises an output part rotating around the axis and connected to outside.

14. The rotation driving device as claimed in claim 13 , wherein the output part is fixed in adjacency to an outer side of the second cylindrical part in the axial direction.

15. The rotation driving device as claimed in claim 13 , wherein the output part is formed on an outer circumference of the second cylindrical part.

16. The rotation driving device as claimed in claim 1 , wherein a detected part is fixed to the rotation shaft in a region outside the second bearing in the axial direction, and
the rotation driving device further comprises a circuit substrate which is provided between the second cover member and the body, and in which a detection sensor detecting a rotation position of the rotation shaft via the detected part and a control circuit controlling driving of the motor are mounted.

Assignees

• Mikuni Kogyo Kk

Inventors

• Shiokawa Hisashi
• Ihara Daiki
• Yagoh Shota
• Takami Katsushi

Classifications

• F16H2057/02082

  for application in vehicles other than propelling, e.g. adjustment of parts · CPC title

• H02K7/08

  Structural association with bearings · CPC title

• H02K7/083

  radially supporting the rotary shaft at both ends of the rotor (H02K7/086, H02K7/09 take precedence) · CPC title

• F16H57/08

  of gearings with members having orbital motion · CPC title

• H02K11/215

  Magnetic effect devices, e.g. Hall-effect or magneto-resistive elements · CPC title