Method and system to prevent vehicle driveaway during battery charging

• US 8,863,870 B2
• Filed: 01/07/2013
• Issued: 10/21/2014
• Est. Priority Date: 06/18/2009
• Status: Active Grant

• Current Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Original Assignee: Ford Global Technologies, LLC (Ford Motor Company)
• Inventors: Gwozdek, Thomas M., Lathrop, James A., Lovett, Karin, Mils, Jerry
• Primary Examiner(s): Restifo, Jeffrey J
• Application Number:
  US13/735,488
• Publication Number:
  US 20130123064A1
• Time in Patent Office: 652 Days
• Field of Search: 180/65.31, 320/107, 320/109, 320/104
• US Class Current: 180/65.31
• CPC Class Codes: B60T 17/18 Safety devices; Monitoring
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/08 including control of electric propulsion units, e.g. motors or generators
• CPC Class Codes: B60W 10/182 including control of parking brakes
• CPC Class Codes: B60W 10/184 with wheel brakes
• CPC Class Codes: B60W 20/00 Control systems specially adapted for hybrid vehicles hybrid vehicle design, B60K6/00; electric vehicles B60L
• CPC Class Codes: B60W 20/50 Control strategies for responding to system failures, e.g. for fault diagnosis, failsafe operation or limp mode
• CPC Class Codes: B60W 2540/06 Ignition switch
• CPC Class Codes: B60W 2540/12 Brake pedal position
• CPC Class Codes: B60W 30/18054 at stand still, e.g. engine in idling state hill holding B60W30/18118
• CPC Class Codes: F16H 61/22 Locking of the control input devices constructional features of locking or disabling mechanisms F16H63/34
• CPC Class Codes: Y02T 10/62 Hybrid vehicles

Abstract

A system and method are disclosed for preventing driveaway or roll away of a plug-in electric vehicle when it is being charged or is coupled to an external power supply cord. When it is detected based on at least one of the following conditions: a current is flowing to the battery charger, a voltage source is coupled to the battery charger, an access door allowing access to the receptacle on board the vehicle is open and/or a plug detect switch indicates that a plug is coupled with the receptacle, a mechanical restraint on the driveline is prevented from being released. The mechanical restraint may be a parking brake. Alternatively, the mechanical restraint may include preventing the gear shift selector from being moved out of the park position.

Claims

1. A method to prevent vehicle movement when a battery onboard the vehicle is being charged, the vehicle having a mechanical restraint comprising a parking brake configured to restrain at least one wheel of the vehicle and a battery charging receptacle, comprising:

preventing the mechanical restraint from being released while an external power supply cord is plugged into the receptacle.

2. The method of claim 1 wherein the mechanical restraint is applied to a driveline of the vehicle.

3. The method of claim 2, further comprising:

applying the mechanical restraint to the driveline of the vehicle when a vehicle condition is detected indicating that the external power supply cord is plugged into the receptacle and the mechanical restraint is unapplied.

4. The method of claim 1 wherein the parking brake comprises one of:

an electric parking brake, an operator-actuated mechanical parking brake, and an anti-lock brake system.

5. The method of claim 1 wherein:

the parking brake is an operator-actuated mechanical parking brake restraining at least one wheel of the vehicle from rotating;

the vehicle further comprises a parking brake solenoid coupled to the parking brake;

the solenoid has a lock position that prevents release of the parking brake; and

the preventing step comprises maintaining the parking brake solenoid in the lock position.

6. The method of claim 1 wherein:

the vehicle has an access door on the exterior of the vehicle proximate the receptacle;

the access door allows access to the receptacle when open;

the access door is coupled to an access door switch indicating whether the access door is open; and

the preventing step is in response to a signal from the access door switch.

7. The method of claim 1 wherein the receptacle comprises a plug detector switch providing an indication of whether a plug is coupled to the receptacle;

and wherein preventing comprises preventing the mechanical restraint from being released based on a signal from the plug detector switch.

8. The method of claim 7 wherein the plug detector switch comprises a pin switch, which is depressed when a plug end of the external power supply cord is coupled with the receptacle.

9. The method of claim 1 wherein preventing comprises preventing the mechanical restraint from being released when current is being supplied to the battery from the receptacle.

10. The method of claim 1 wherein preventing comprises preventing the mechanical restraint from being released when a voltage source is coupled to the receptacle.

11. A method to prevent vehicle movement when a battery onboard the vehicle is being charged, the vehicle having a parking brake, a battery charging receptacle, and an access door selectively openable to permit access to the receptacle, comprising:

preventing the parking brake from being released while the access door is open.

12. The method of claim 11, wherein the parking brake is an operator-actuated mechanical parking brake;

the vehicle further comprises a parking brake solenoid coupled to the parking brake;

the solenoid has a lock position that prevents release of the parking brake; and

the preventing step comprises maintaining the parking brake solenoid in the lock position.

13. The method of claim 11, wherein the parking brake comprises one of:

an electric parking brake and an anti-lock brake system.

14. The method of claim 11, wherein the access door is coupled to an access door switch indicating whether the access door is open;

and

the preventing step is in response to a signal from the access door switch.