Method And System To Prevent Vehicle Driveaway During Battery Charging

• US 20130123064A1
• Filed: 01/07/2013
• Published: 05/16/2013
• 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
• Granted Patent: US 8,863,870 B2
• Time in Patent Office: Days
• US Class Current: 477/7
• 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 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 mechanical restraint comprises a parking brake restraining at least one wheel of the vehicle from rotating and the preventing step comprises preventing release of the parking brake.

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

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

6. The method of claim 1 wherein:

the mechanical restraint comprises 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.

7. 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 vehicle condition is based on a signal from the access door switch.

8. 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.

9. The method of claim 8 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.

10. 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.

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

12. A vehicle system, comprising:

an electric motor,

a battery electrically coupled to the electric motor;

a receptacle coupled to the battery, the receptacle being adapted to couple with a plug of an external power supply cord to charge the battery from an external electric power supply;

a driveline mechanically coupled to the electric motor;

wheels coupled to the driveline;

a mechanical restraint coupled to the driveline, the mechanical restraint preventing rotation of at least one wheel when applied; and

an electronic control unit electronically coupled to the vehicle, the electronic control unit preventing release of the mechanical restraint when a vehicle signal indicates at least one of;

a plug is coupled with the receptacle, and an access door proximate the receptacle is open.

13. The system of claim 12, further comprising:

an access door switch mechanically coupled to the access door and electronically coupled to the electronic control unit, wherein a signal from the access door switch provides the vehicle signal.

14. The system of claim 12 wherein the vehicle signal is based on an indication that one of a voltage and a current is being applied to the battery via the receptacle.

15. The system of claim 12, further comprising:

a plug detect switch coupled to the receptacle wherein the plug detect switch is depressed by the plug when it couples with the receptacle and the vehicle signal comprises a signal from the plug detect switch.

16. The system of claim 15, further comprising:

brakes adapted to restrain at least one wheel from rotating wherein the mechanical restraint comprises the brakes.

17. A plug-in vehicle system, comprising:

an electric motor,

a battery electrically coupled to the electric motor;

a battery charger electrically coupled to the battery;

an operator actuated gear shift selector;

a solenoid proximate the gear shift selector and configured to selectively lock the gear shift selector;

a receptacle coupled to the battery charger, the receptacle being adapted to couple with a plug of an external power supply cord to charge the battery from an external electric power supply;

a driveline mechanically coupled to the electric motor;

wheels coupled to the driveline;

a mechanical restraint coupled to the driveline, the mechanical restraint preventing rotation of at least one wheel when applied; and

an electronic control unit electronically coupled to the vehicle, the electronic control unit actuating the solenoid to lock the gear shift selector and preventing release of the mechanical restraint when a vehicle signal indicates at least one of;

a plug is coupled with the receptacle and an access door proximate the receptacle is open.

18. The system of claim 17, further comprising:

an access door switch mechanically coupled to the access door and electronically coupled to the electronic control unit, wherein a signal from the access door switch provides the vehicle signal.

19. The system of claim 17 wherein the vehicle signal is based on an indication that one of a voltage and a current is being applied to the battery charger.

20. The system of claim 17, further comprising:

a plug detect switch coupled to the receptacle wherein the plug detect switch is depressed by the plug when it couples with the receptacle and the vehicle signal comprises a signal from the plug detect switch.