Actuator with reverse input blocking clutch, steering device, and reverse input blocking clutch control method

Patent metadata

Field	Value
Publication number	US-12060116-B2
Application number	US-202318684209-A
Country	US
Kind code	B2
Filing date	Jun 13, 2023
Priority date	Jun 23, 2022
Publication date	Aug 13, 2024
Grant date	Aug 13, 2024

Abstract

An actuator with reverse input blocking clutch has a function of switching the reverse input blocking clutch to a state in which torque can be transmitted between an input member and an output member, in a state in which reverse torque is input to the output member from an output-side mechanism, by applying torque to the input member by an actuator in an opposite direction to a direction of the reverse torque, and then by giving an instruction to the actuator to apply torque having a magnitude smaller than a magnitude of the reverse torque to the input member in the opposite direction, transmitting the reverse torque to the input member.

First claim

The invention claimed is:

1. An actuator with reverse input blocking clutch, comprising:
an actuator; and
a reverse input blocking clutch including an input member rotatably driven by the actuator, and an output member connected to an output-side mechanism so as to transmit torque, and when torque is input to the input member from the actuator in a state in which torque is not reversely input to the output member from the output-side mechanism, transmitting the torque input to the input member to the output member; and when torque is reversely input to the output member from the output-side mechanism in a state in which torque is not input to the input member from the actuator, locking rotation of the output member;
the actuator with reverse input blocking clutch having a function of switching the reverse input blocking clutch to a state in which torque can be transmitted between the input member and the output member, in a state in which torque is being reversely input to the output member from the output-side mechanism, by the actuator applying torque to the input member in an opposite direction to a direction of the torque that is reversely input to the output member from the output side mechanism, and then continuously giving an instruction to the actuator to apply torque having a magnitude smaller than a magnitude of the torque being reversely input to the output member from the output side mechanism to the input member in the opposite direction, transmitting the torque being reversely input to the output member from the output side mechanism to the input member.

2. The actuator with reverse input blocking clutch according to claim 1 ,
wherein the actuator comprises an electric motor.

3. The actuator with reverse input blocking clutch according to claim 1 , wherein
the reverse input blocking clutch comprises:
a pressed member having a pressed surface on an inner peripheral surface thereof;
the input member having an input-side engaging portion arranged on an inner side in a radial direction of the pressed surface, and rotatably supported coaxially with the pressed surface;
an output member having an output-side engaging portion arranged farther on the inner side in the radial direction than the input-side engaging portion on the inner side in the radial direction of the pressed surface, and rotatably supported coaxially with the pressed surface; and
an engaging element having a pressing surface that faces the pressed surface, an input-side engaged portion capable of engaging with the input-side engaging portion, and an output-side engaged portion capable of engaging with the output-side engaging portion; the engaging element being arranged so as to move in a first direction that is a direction in which the pressing surface separates from or approaches the pressed surface; wherein
the engaging element, when torque is input from the actuator to the input member, moves in a direction in which the pressing surface is separated from the pressed surface in the first direction due to engagement between the input-side engaging portion and the input-side engaged portion, allowing torque transmission between the input member and the output member, whereas, when torque is reversely input to the output member from the output-side mechanism in a state in which torque is not being input to the input member from the actuator to the input member, the engaging element is pressed in a direction that brings the pressing surface closer to the pressed surface in the first direction, causing the pressing surface to frictionally engage with the pressed surface.

4. The actuator with reverse input blocking clutch according to claim 3 , wherein the engaging element has two pressing surfaces respectively configured by the pressing surface at two positions spaced apart in a circumferential direction on an outer side surface in the radial direction.

5. The actuator with reverse input blocking clutch according to claim 4 , wherein
in a state in which, as the output member rotates to one side in the circumferential direction, the two pressing surfaces are pressed against the pressed surface, and as the input member rotates to the other side in the circumferential direction, the input-side engaging portion engages with the input-side engaged portion, a distance in a second direction perpendicular to both the first direction and a rotation center of the input member between a contact portion between the input-side engaging portion and the input-side engaged portion and the rotation center of the input member is smaller than a distance in the second direction between a contact portion between the output-side engaging portion and the output-side engaged portion and a rotation center of the output member; and
in a state in which torque is reversely input to the output member and the two pressing surfaces are in contact with the pressed surface, the contact portion between the output-side engaging portion and the output-side engaged portion is located on a side closer to the rotation center of the output member in the first direction than an imaginary line connecting a contact portion between one pressing surface of the two pressing surfaces and the pressed surface and the rotation center of the output member.

6. The actuator with reverse input blocking clutch according to claim 4 , wherein
in a state in which, as the output member rotates to one side in a circumferential direction, the two pressing surfaces are pressed against the pressed surface, and as the input member rotates to the other side in the circumferential direction, the input-side engaging portion engages with the input-side engaged portion, a distance in a second direction perpendicular to both the first direction and a rotation center of the input member between a contact portion between the input-side engaging portion and the input-side engaged portion and the rotation center of the input member is larger than a distance in the second direction between a contact portion between the output-side engaging portion and the output-side engaged portion and the rotation center of the output member; and
in a state in which torque is reversely input to the output member and the two pressing surfaces are in contact with the pressed surface, the contact portion between the output-side engaging portion and the output-side engaged portion is located on a side closer to the rotation center of the output member in the first direction than an imaginary line connecting a contact portion between one pressing surface of the two pressing surfaces and the pressed surface and the rotation center of the output member.

7. The actuator with reverse input blocking clutch according to claim 3 , wherein the reverse input blocking clutch comprises two engaging elements configured by the engaging element.

8. The actuator with reverse input blocking clutch according to claim 3 , wherein the reverse input blocking clutch comprises an elastic member configured to elastically bias the engaging element in a direction that brings the pressing surface closer to the pressed surface.

9. A steering device, comprising:
an actuator with reverse input blocking clutch having an output member; and
a linear motion mechanism having a rod that is supported so as to perform linear motion and is connected to steered wheels so that a direction of the steered wheels changes in accordance with the linear motion, the linear motion mechanism configured to convert rotational motion of the output member into linear motion of the rod; wherein
the actuator with reverse input blocking clutch is configured by the actuator with reverse input blocking clutch according to claim 1 .

10. The steering device according to claim 9 , wherein

Assignees

• Nsk Ltd

Inventors

• Yamamoto Shin
• Maeda Atsushi
• Kaneko Shohei
• KYO Cyou
• Saito Hideyuki

Classifications

• F16D43/211 Primary

  with radially applied torque-limiting friction surfaces · CPC title

• B62D5/043 Primary

  characterised by clutch means between driving element, e.g. motor, and driven element, e.g. steering column or steering gear · CPC title

• F16D41/08

  with provision for altering the freewheeling action · CPC title

• F16D23/12

  Mechanical clutch-actuating mechanisms arranged outside the clutch as such (specific for combined clutches F16D21/00; mechanisms specific for synchronisation F16D23/02) · CPC title

• F16D43/02

  actuated entirely mechanically · CPC title