DRIVER AND DRIVER-INTEGRATED ELECTRIC ACTUATOR

• US 20180202571A1
• Filed: 07/27/2016
• Published: 07/19/2018
• Est. Priority Date: 08/31/2015
• Status: Active Grant

• Current Assignee: Hitachi Astemo Ltd. (Hitachi, Ltd.)
• Original Assignee: Hitachi Automotive Systems Limited (Hitachi, Ltd.)
• Inventors: FUKUZAWA, Takayuki, KAWAI, Yoshio, KANEKO, Yujiro
• Granted Patent: US 10,641,409 B2
• Time in Patent Office: Days
• CPC Class Codes: F16K 31/06 using a magnet , e.g. diaphragm valves, cutting off by means of a liquid
• CPC Class Codes: F16K 49/00 Means in or on valves for heating or cooling heating or cooling of pipes or pipe systems F16L53/00; thermal insulation in connection with pipes or pipe systems F16L59/16
• CPC Class Codes: H01F 7/064 Circuit arrangements for actuating electromagnets circuit arrangements for obtaining special operating characteristics H01F7/18; driving circuits for electromagnets making use of a switching regulator H01H47/325
• CPC Class Codes: H01F 7/16 Rectilinearly-movable armatures H01F7/17 takes precedence
• CPC Class Codes: H02K 11/0141 Shields associated with casings, enclosures or brackets
• CPC Class Codes: H02K 11/33 Drive circuits, e.g. power electronics H02K11/38 takes precedence
• CPC Class Codes: H02K 33/02 with armatures moved one way by energisation of a single coil system and returned by mechanical force, e.g. by springs
• CPC Class Codes: H02K 9/223 Heat bridges
• CPC Class Codes: H05K 7/12 Resilient or clamping means for holding component to structure

Abstract

Provided are a driver and a driver-integrated electric actuator that can suppress a temperature rise of the driver integrated with an electric actuator. A driver circuit of an electric actuator-integrated driver controls a current to be supplied to an electric actuator. A metal member (heat-conducting portion) conducts heat generated in the driver circuit. A driver sealing portion is fixed to the electric actuator and seals the driver circuit and the metal member. The metal member is extended to the electric actuator.

Claims

1. A driver comprising:

a driver circuit that controls a current to be supplied to an electric actuator;

a heat-conducting portion that conducts heat generated in the driver circuit; and

a sealing portion that is fixed to the electric actuator and seals the driver circuit and the heat-conducting portion,

wherein the heat-conducting portion is extended to the electric actuator.

2. The driver according to claim 1, wherein

the heat-conducting portion mounts the driver circuit.

3. The driver according to claim 2, wherein

a distal end of the heat-conducting portion extended to the electric actuator is adjacent to a component of the electric actuator to be cooled.

4. The driver according to claim 2, wherein

the electric actuator controls a hydraulic oil to be used in an onboard device, and

a distal end of the heat-conducting portion extended to the electric actuator is adjacent to a component of the electric actuator to be cooled by the hydraulic oil.

5. The driver according to claim 2, wherein

the heat-conducting portion comprises:

a first part that mounts the driver circuit and extends in an axial direction of the electric actuator; and

a second part that extends from one end of the first part in a direction crossing an axis of the electric actuator.

6. The driver according to claim 5, wherein

the second part of the heat-conducting portion is thicker than the first part of the heat-conducting portion.

7. The driver according to claim 5, wherein

the heat-conducting portion further comprises a third part that extends from one end of the second part in the axial direction of the electric actuator.

8. The driver according to claim 5, further comprising

a metal block that is adjacent to the first part and the second part of the heat-conducting portion.

9. The driver according to claim 2, wherein

the electric actuator comprises:

a fixed core that is a magnetic body;

an electromagnetic coil that is wound around the fixed core;

a valve that is driven depending on an electromagnetic force of the electromagnetic coil; and

a body portion that is in contact with the fixed core and slidably holds the valve, and

a distal end of the heat-conducting portion extended to the electric actuator is adjacent to the fixed core.

10. The driver according to claim 9, wherein

the electric actuator further comprises a bobbin which is inserted through the fixed core and around which the electromagnetic coil is wound, and

the sealing portion is formed integrally with the bobbin.

11. The driver according to claim 9, wherein

the electric actuator further comprises a bobbin which is inserted through the fixed core and around which the electromagnetic coil is wound,

the sealing portion is in contact with the bobbin and the fixed core, and

thermal conductivity of the sealing portion is higher than thermal conductivity of the bobbin.

12. The driver according to claim 2, further comprising

at least one external wiring terminal that is connected to an external wiring through which a control signal of the driver circuit propagates or at least one electromagnetic coil terminal that is connected to the electromagnetic coil,

wherein the heat-conducting portion is integrated with at least one of the external wiring terminal and the electromagnetic coil terminal.

13. The driver according to claim 12, wherein

the external wiring terminal or the electromagnetic coil terminal, which is integrated with the heat-conducting portion, is thicker than the external wiring terminal or the electromagnetic coil terminal that is not integrated with the heat-conducting portion.

14. The driver according to claim 5, wherein

the heat-conducting portion further comprises a fourth part that extends from another end of the first part in a direction crossing the axis of the electric actuator and is adjacent to a housing of the electric actuator.

15. The driver according to claim 2, wherein

the heat-conducting portion comprises a shielding wall that shields an electromagnetic wave from outside or the electromagnetic coil.

17. The driver according to claim 1, wherein

the heat-conducting portion is in contact with the electric actuator.

18. The driver according to claim 17, further comprising

a dissimilar member that is arranged between the heat-conducting portion and the driver circuit and represents a member made of a different material from the seal portion.

19. The driver according to claim 18, further comprising

a bonding wire that is buried in the dissimilar member and electrically connected to the driver circuit.

20. The driver according to claim 17, further comprising:

a base on which the driver circuit is mounted; and

a dissimilar member that is arranged between the base and the heat-conducting portion and represents a member made of a different material from the seal portion.

21. The driver according to claim 17, wherein

the electric actuator comprises:

a coil bobbin that is constituted by an electromagnetic coil and a bobbin around which the electromagnetic coil is wound;

a fixed-core portion that holds the coil bobbin;

a valve that is driven depending on an electromagnetic force of the electromagnetic coil;

a valve portion that holds the valve; and

an electric actuator housing that holds the coil bobbin, the fixed-core portion, the valve, and the valve portion,

wherein the heat-conducting portion is in contact with the valve portion.

22. The driver according to claim 17, wherein

the heat-conducting portion is surface-treated.

23. The driver according to claim 17, wherein

the heat-conducting portion comprises a metal shielding wall that covers the driver circuit.

24. The driver according to claim 17, wherein

the heat-conducting portion comprises an externally-exposed portion that is exposed to outside of the sealing portion.

25. The driver according to claim 24, wherein

the electric actuator controls a fluid passing through a flow path provided in a metal housing, and

the externally-exposed portion is connected to the metal housing via a heat-dissipating member.

26. The driver according to claim 17, further comprising

a base on which the driver circuit is mounted,

wherein the base is in contact with the electric actuator.

16. A driver-integrated electric actuator comprising:

an electric actuator;

a driver circuit that controls a current to be supplied to the electric actuator;

a heat-conducting portion that mounts the driver circuit and conducts heat generated in the driver circuit; and

a driver that is fixed to the electric actuator and comprises a sealing portion that seals the driver circuit and the heat-conducting portion,

wherein the heat-conducting portion is extended to the electric actuator.