Integral-type electric power steering device

Patent metadata

Field	Value
Publication number	US-10017203-B2
Application number	US-201214351967-A
Country	US
Kind code	B2
Filing date	May 28, 2012
Priority date	Jan 17, 2012
Publication date	Jul 10, 2018
Grant date	Jul 10, 2018

Abstract

An integral-type electric power steering device is configured in such a way that a motor component, a reduction mechanism, and a control device are integrally fixed, and the control device includes at least heating elements which are operated for control and which generate heat, a control board on which the heating elements are mounted, and mechanism components for fixing the control board; and at least a part of the heat, which is generated by the heating elements, is conducted to the mechanism components via a thermal-conductive component.

First claim

What is claimed is:

1. An integral-type electric power steering device comprising:
a motor component including a motor that generates an assist torque corresponding to a steering torque caused by a driver in a car and applies the generated assist torque to a steering shaft of the car via a reduction mechanism; and
a control device which controls the motor, wherein:
the control device comprises at least heating elements, which are operated for control and generate heat, a control board on which the heating elements are mounted, and a mechanism component to which the control board is fixed,
at least a part of the heat, which is generated by the heating elements, is conducted to the mechanism component via a thermal-conductive component,
wherein the mechanism component comprises a first part, which is a reduction-mechanism-side case for the reduction mechanism, and a second part, which is a motor-side case for the motor component,
wherein at least one of the first part and the second part abuts the thermal-conductive component forming a thermal conductive passage between the heating elements and the mechanism component, and
wherein the thermal-conductive component is arranged at a position corresponding to a location of the heating elements and is substantially smaller than the control board.

2. An integral-type electric power steering device as recited in claim 1 , wherein the motor component and the control device are being integrally fixed to each other in a longitudinal direction of the rotor shaft of the motor on a same axis.

3. An integral-type electric power steering device as recited in claim 2 , wherein a wall surface of the reduction-mechanism-side case and a wall surface of the motor-side case are arranged in a vertical direction with respect to the longitudinal direction of the rotor shaft.

4. An integral-type electric power steering device as recited in claim 1 , wherein the motor component is arranged between the reduction mechanism and the control device, and
the mechanism components include a motor-side case, which is connected to the motor component, and a motor-opposite-side case, and the control board is fixed to the motor-side case, and the heating elements are mounted on a surface of the control board, which faces to a wall surface of the motor-side case, and the thermal-conductive component is arranged between the heating elements and the wall surface of the motor-side case.

5. An integral-type electric power steering device as recited in claim 4 , wherein the motor-side case includes a convex portion, which is contacted to the thermal-conductive component, on the wall surface.

6. An integral-type electric power steering device as recited in claim 4 , wherein the control device further comprises a power-circuit element, which control power supplied to the motor, and a power board on which at least the power-circuit element is mounted, and the power board is contacted to the motor-side case so as to be mounted.

7. An integral-type electric power steering device as recited in claim 4 , wherein a control-device-integrated motor is configured in such a way that the motor component and the control device are integrally fixed to a rotor shaft of the motor in a direction where the rotor shaft is extended.

8. An integral-type electric power steering device as recited in claim 1 , wherein the motor component is arranged between the reduction mechanism and the control device, and the mechanism components include a motor-side case, which is connected to the motor component, and a motor-opposite-side case, and the control board is fixed to the motor-side case, and the heating elements are mounted on a surface of the control board, which faces to a wall surface of the motor-opposite-side case, and the thermal-conductive component is arranged between the heating elements and the wall surface of the motor-opposite-side case.

9. An integral-type electric power steering device as recited in claim 8 , wherein the motor-side case includes a convex portion, which is contacted to the thermal-conductive component, on the wall surface.

10. An integral-type electric power steering device as recited in claim 9 , wherein the wall surface of the reduction-mechanism-side case and the wall surface of the motor-opposite-side case are arranged in a vertical direction with respect to the direction where the rotor shaft is extended.

11. An integral-type electric power steering device as recited in claim 1 , wherein the thermal-conductive component is formed in a sheet shape.

12. An integral-type electric power steering device as recited in claim 1 , wherein the thermal-conductive component is made from a thermal-curable resin.

13. An integral-type electric power steering device as recited in claim 1 , wherein the reduction-mechanism-side case comprises a convex portion, which contacts with the thermal-conductive component.

14. An integral-type electric power steering device as recited in claim 1 , wherein the thermal-conductive component is approximately same size as a respective one of the heating elements and is arranged directly parallel to the respective one of the heating elements.

15. An integral-type electric power steering device as recited in claim 1 , wherein the thermal-conductive component is dedicated to one of the heating elements.

16. An integral-type electric power steering device comprising:
a motor component including a motor that generates an assist torque corresponding to a steering torque caused by a driver in a car and applies the generated assist torque to a steering shaft of the car via a reduction mechanism; and
a control device which controls the motor, wherein:
the control device comprises at least heating elements, which are operated for control and generate heat, a control board on which the heating elements are mounted, and a mechanism component to which the control board is fixed,
at least a part of the heat, which is generated by the heating elements, is conducted to the mechanism component via a thermal-conductive component, and
wherein the control device is arranged between the reduction mechanism and the motor component, and the mechanism component comprises a reduction-mechanism-side case, which is connected to the reduction mechanism, and a motor-side case, which is connected to the motor component, and the control board is fixed to the reduction-mechanism-side case, and the heating elements are mounted on a surface of the control board which faces a wall surface of the motor-side case, and the thermal-conductive component is arranged between the heating elements and the wall surface of the motor-side case.

17. An integral-type electric power steering device as recited in claim 16 , wherein the control device further comprises a power-circuit element, which control power supplied to the motor, and a power board on which at least the power-circuit element is mounted, and the power board is contacted to the reduction-mechanism-side case so as to be mounted.

18. An integral-type electric power steering device comprising:
a motor component including a motor that generates an assist torque corresponding to a steering torque caused by a driver in a car and applies the generated assist torque to a steering shaft of the car via a reduction mechanism; and
a control device which controls the motor, wherein:
the control device comprises at least heating elements, which are operated for control and generate heat, a control board on which the heating elements are mounted, and a mechanism component to which the control board is fixed,
at leas

Assignees

• Tanaka Daisuke
• Asao Yoshihito
• Mitsubishi Electric Corp

Inventors

• Tanaka Daisuke
• Asao Yoshihito

Classifications

• B62D5/0406

  including housing for electronic control unit · CPC title

• B62D5/0409 Primary

  Electric motor acting on the steering column · CPC title

• H02K11/33

  Drive circuits, e.g. power electronics (H02K11/38 takes precedence) · CPC title

• H02K7/1166

  comprising worm and worm-wheel (structural association with bearings specially adapted for worm gear drives H02K7/081) · CPC title

• H02K11/225

  Detecting coils · CPC title