Low power, high torque actuator retention

• US 20040187620A1
• Filed: 03/25/2003
• Published: 09/30/2004
• Est. Priority Date: 03/25/2003
• Status: Active Grant

• Current Assignee: Delphi Technologies Ip Limited (BorgWarner Incorporated)
• Original Assignee: Delphi Technologies, Inc. (BorgWarner Incorporated)
• Inventors: Hazelton, Lawrence Dean, Newman, Thomas Wayne, Stege, Jeffrey Jean, Gyoergy, Thomas E., Robinson, Chris D.
• Granted Patent: US 6,964,213 B2
• Time in Patent Office: Days
• US Class Current: 74/411.5
• CPC Class Codes: F16D 2121/20 using electromagnets
• CPC Class Codes: F16D 63/006 Positive locking brakes
• CPC Class Codes: F16H 63/3416 Parking lock mechanisms or brakes in the transmission
• CPC Class Codes: F16H 63/3425 characterised by pawls or wheels
• CPC Class Codes: F16H 63/3441 Parking locks engaging axially
• CPC Class Codes: F16H 63/3475 using solenoids
• CPC Class Codes: Y10T 74/1418 Preselected indexed position
• CPC Class Codes: Y10T 74/1488 Control means
• CPC Class Codes: Y10T 74/1494 Locking means
• CPC Class Codes: Y10T 74/19637 with brake means for gearing
• CPC Class Codes: Y10T 74/20654 Gear

Abstract

A smart actuator and method includes an actuating device adapted to deliver a selected driving torque to a geartrain that is coupled to an output shaft and adapted to selectively convey the driving torque from the actuating device to the output shaft to achieve a selected shaft position. At least one logic and control device operates the various aspects of the smart actuator. The geartrain includes at least one locking gear including locking features defining a plurality of gear positions. A position lock solenoid is adapted to engage the locking gear at a selected gear position once the geartrain has achieved the selected shaft position on the output shaft. The position lock solenoid then holds the gear at the selected gear position. The actuating device is shut off after the position lock solenoid has engaged the locking gear thereby achieving and holding a high torque without driving a lot of current.

Claims

1. A smart actuator comprising:

an actuating device adapted to deliver a selected driving torque to a gear train;

said gear train being coupled to an output shaft and adapted to selectively convey the driving torque from the actuating device to said output shaft to achieve a selected shaft position on said output shaft;

said gear train comprising at least one locking gear including a plurality of locking features defining a plurality of selectively engageable gear positions;

a position lock solenoid adapted to engage said at least one locking gear in a selected gear position once said gear train has achieved said selected shaft position on said output shaft and to hold said locking gear at said selected gear position thereby holding said selected shaft position;

wherein said actuating device is shut off after said position lock solenoid has engaged said locking gear; and

at least one logic and control device for operating the various aspects of the smart actuator.

2. The smart actuator of claim 1, wherein said actuating device comprises an electric actuator.

3. The smart actuator of claim 1, wherein said locking features are located on a bottom surface of said locking gear.

4. The smart actuator of claim 1, wherein said locking features comprise conical shaped detent features.

5. The smart actuator of claim 1, wherein said position lock solenoid includes a rod-shaped member having a cap at a first end and ending in a tapered engaging tip at a second end for engaging a selected locking feature on said locking gear.

6. The smart actuator of claim 1, wherein said at least one logic and control device comprises an on-board control unit.

7. The smart actuator of claim 1, wherein said at least one logic and control device is further coupled with additional logic and control devices.

8. The smart actuator of claim 1, wherein said at least one logic and control device is further coupled with an engine control unit.

9. A method for transmitting and holding a torque level employing a smart actuator comprising:

delivering a selected driving torque to a gear train via an actuating device coupled to said gear train, said gear train being further coupled to an output shaft and adapted to selectively convey the driving torque from the actuating device to said output shaft;

selectively conveying the driving torque delivered from the actuating device to the gear train to said output shaft to achieve a selected position on said output shaft;

said gear train comprising at least one locking gear including a plurality of locking features defining a plurality of selectively engageable gear positions;

selectively activating a position lock solenoid adapted to engage said locking gear at a selected gear position once said gear train has achieved said selected position on said output shaft and thereby holding said gear in said selected position for a selected period of time;

shutting off said actuating device after said position lock solenoid has engaged said locking gear; and

employing at least one logic and control device for operating the various aspects of the smart actuator.

10. The method of claim 9, wherein said actuating device comprises an electric actuator.

11. The method of claim 9, wherein said locking features are located on a bottom surface of said locking gear.

12. The method of claim 9, wherein said locking features comprise conical shaped detent features.

13. The method of claim 9, wherein said position lock solenoid includes a rod-shaped member having a cap at a first end and ending in a tapered engaging tip at a second end for engaging a selected locking feature on said locking gear.

14. The method of claim 9, wherein said at least one logic and control device comprises an on-board control unit.

15. The method of claim 9, wherein said at least one logic and control device is further coupled with additional logic and control devices.

16. The method of claim 9, wherein said at least one logic and control device is further coupled with an engine control unit.