Reaction force actuator and steering device

Patent metadata

Field	Value
Publication number	US-9683639-B2
Application number	US-201514862774-A
Country	US
Kind code	B2
Filing date	Sep 23, 2015
Priority date	Mar 5, 2015
Publication date	Jun 20, 2017
Grant date	Jun 20, 2017

Abstract

A reaction force actuator to be used in a steer-by-wire steering device includes an operating-side shaft, a motor, and a friction drive transmission. The operating-side shaft rotates integrally with an operating member that a driver operates. The motor includes a cylindrical motor output shaft disposed coaxially on an outer circumference of the operating-side shaft. The friction drive transmission changes a speed of a rotary motion of the motor output shaft and transmits the rotary motion to the operating-side shaft.

First claim

What is claimed is:

1. A reaction force actuator to be used in a steer-by-wire steering device, comprising:
an operating-side shaft that rotates integrally with an operating member that a driver operates;
a motor that comprises a cylindrical motor output shaft disposed coaxially on an outer circumference of the operating-side shaft; and
a friction drive transmission that changes a speed of a rotary motion of the motor output shaft and transmits the rotary motion to the operating-side shaft, wherein
the friction drive transmission comprises:
a sun roller fixed coaxially on an outer circumference of the motor output shaft;
a plurality of planetary rollers disposed on an outer circumference of the sun roller to make contact with an outer circumferential surface of the sun roller;
a non-rotating ring that is inscribed by the planetary rollers; and
a carrier that rotatably supports the planetary rollers and is directly fixed to the operating-side shaft.

2. The reaction force actuator according to claim 1 , further comprising:
a connecting and disconnecting device that connects and disconnects transmission of power between the operating-side shaft and a steered wheel-side shaft connected to a steered wheel.

3. The reaction force actuator according to claim 2 , wherein
a carrier roller that is fixed to the operating-side shaft,
each of the planetary rollers comprises a main body that makes contact with the sun roller and the ring, and a driving unit that is disposed coaxially with the main body and has a diameter different from that of the main body, and
the carrier roller makes contact with the driving unit.

4. The reaction force actuator according to claim 3 , wherein
the driving unit has a truncated conical shape that is coaxial with the main body.

5. A steer-by-wire steering device comprising:
the reaction force actuator according to claim 1 .

6. A steer-by-wire steering device comprising:
the reaction force actuator according to claim 2 .

7. A reaction force actuator to be used in a steer-by-wire steering device, comprising:
an operating-side shaft that rotates integrally with an operating member that a driver operates;
a motor that comprises a cylindrical motor output shaft disposed coaxially on an outer circumference of the operating-side shaft; and
a friction drive transmission that changes a speed of a rotary motion of the motor output shaft and transmits the rotary motion to the operating-side shaft, wherein
the friction drive transmission comprises:
a sun roller that is fixed coaxially on an outer circumference of the motor output shaft;
a plurality of planetary rollers that are disposed on an outer circumference of the sun roller so as to make contact with an outer circumferential surface of the sun roller;
a non-rotating ring that is inscribed by the planetary rollers; and a carrier roller that is fixed to the operating-side shaft,

each of the planetary rollers comprises a main body that makes contact with the sun roller and the ring, and a driving unit that is disposed coaxially with the main body and has a diameter different from that of the main body, and
the carrier roller makes contact with the driving unit.

8. The reaction force actuator according to claim 7 , wherein
the driving unit has a truncated conical shape that is coaxial with the main body.

9. A steer-by-wire steering device comprising:
the reaction force actuator according to claim 8 .

10. A steer-by-wire steering device comprising:
the reaction force actuator according to claim 7 .

Assignees

• Showa Corp

Inventors

• Kogure Akihiro

Classifications

• B62D5/043

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

• B62D5/006 Primary

  power actuated · CPC title

• B62D5/0415

  the axes being coaxial · CPC title

• F16H15/50 Primary

  Gearings providing a continuous range of gear ratios · CPC title