VEHICLE SPEED LIMITING VIA ENGINE CONTROL COMMANDS BASED ON SENSED MACHINE STATE

• US 20130345914A1
• Filed: 06/25/2012
• Published: 12/26/2013
• Est. Priority Date: 06/25/2012
• Status: Abandoned Application

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Love, Kraig, Wilson, Arvil
• Application Number:
  US13/531,621
• Publication Number:
  US 20130345914A1
• Time in Patent Office: Days
• US Class Current: 701/22
• CPC Class Codes: B60K 2031/0091 Speed limiters or speed cutters
• CPC Class Codes: B60K 31/047 the memory being digital
• 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 10/11 Stepped gearings
• CPC Class Codes: B60W 2510/104 Output speed
• CPC Class Codes: B60W 2710/0644 Engine speed
• CPC Class Codes: B60W 2710/0666 Engine torque
• CPC Class Codes: B60W 2710/0677 Engine power
• CPC Class Codes: B60W 30/146 Speed limiting

Abstract

A machine includes a drive train with an electronically controlled transmission in communication with an electronic engine controller. The machine ground speed is limited by executing a vehicle speed limit algorithm in the electronic transmission controller in response to a sensed machine state. This algorithm generates an engine control message that is communicated to the electronic engine controller. The power output of the engine is reduced responsive to the engine control message. The machine responds by not exceeding a prescribed speed limit programmed into the electronic transmission controller. This vehicle speed limiting strategy is particularly applicable to machines without a vehicle speed limiting algorithm resident in the electronic engine controller.

Claims

1. A method of limiting ground speed of a machine, comprising the steps of:

propelling the machine at a speed by transmitting engine power to a ground engaging member of the machine via a drive train that includes a transmission;

sensing at least one machine state in an electronic transmission controller,

selecting a vehicle speed limit in the electronic transmission controller in response to the at least one machine state,

executing a vehicle speed limit algorithm in the electronic transmission controller to determine an engine control message;

communicating the engine control message to an electronic engine controller via a communication link; and

limiting the speed responsive to the engine control message by executing an engine control algorithm in an electronic engine controller.

2. The method of claim 1 including a step of storing a vehicle speed limit in a memory coupled to the electronic transmission controller.

3. The method of claim 1 including a step of storing data relating vehicle speed to transmission output speed in a memory coupled to the electronic transmission controller.

4. The method of claim 1 including a step of determining a transmission gear ratio.

5. The method of claim 1 wherein the engine control message is part of a standardized torque/speed control message communicated via a public data bus communication standard.

6. The method of claim 5 wherein the engine control message is contained in a speed limit data field of a Torque/Speed Control #1 (TSC1) message of an SAE J1939 data bus communication standard.

7. The method of claim 5 wherein the engine control message is contained in a torque limit data field of a Torque/Speed Control #1 (TSC1) message of an SAE J1939 data bus communication standard.

8. The method of claim 1 wherein the engine control message includes an engine power limit.

9. The method of claim 1 wherein the step of executing the vehicle speed limit algorithm includes determining which of a speed limit and a torque limit to include in the engine control message.

10. The method of claim 1 wherein the step of executing the vehicle speed limit algorithm includes determining the speed of the machine;

determining if the speed is within a predetermined tolerance of a predetermined speed limit; and

generating the engine control message if the speed is within the predetermined tolerance of the predetermined speed limit.

11. The method of claim 1 including a step of determining a failure in at least one of the executing a vehicle speed limit algorithm step and the communicating step;

and

enabling a gear binding speed limit algorithm responsive to the failure.

12. The method of claim 11 including a step of storing a vehicle speed limit in a memory coupled to the electronic transmission controller;

storing data relating vehicle speed to transmission output speed in a memory coupled to the electronic transmission controller;

the engine control message is part of a standardized torque/speed control message communicated via a public data bus communication standard;

the step of executing the vehicle speed limit algorithm includes determining the speed of the machine;

determining if the speed is within a predetermined tolerance of a predetermined speed limit; and

generating the engine control message only if the speed is within the predetermined tolerance of the predetermined speed limit.

21. The method of claim 1 wherein the at least one machine state corresponds to a position of a dump body.

22. The method of claim 1 wherein the drive train includes an engine;

and

wherein the at least one machine state indicates operation of a power take off powered by said engine.

13. A transmission comprising:

a housing;

an electronic transmission controller attached to the housing and including means for establishing a communication link with an electronic engine controller; and

the electronic transmission controller being configured to sense at least one machine state, select a vehicle speed in response to the at least one machine state, and execute a vehicle speed limit algorithm to generate an engine control message.

14. The transmission of claim 13 including means for storing a vehicle speed limit and data relating vehicle speed to transmission output speed in a memory coupled to the electronic transmission controller.

15. The transmission of claim 14 wherein the electronic transmission controller is configured for communication according to an SAE J1939 data bus communication standard.

16. The transmission of claim 15 including means for executing a gear binding speed limiting algorithm responsive to a predetermined failure.

23. The transmission of claim 13 wherein the at least one machine state corresponds to a position of a dump body.

24. The transmission of claim 13 wherein the drive train includes an engine;

and

wherein the at least one machine state indicates operation of a power take off powered by said engine.

17. A machine comprising:

a chassis;

a plurality of ground engaging members attached to the chassis;

a drive train that includes an engine coupled to the ground engaging members attached to the chassis;

the drive train including a transmission with an electronic transmission controller;

the electronic transmission controller being configured to sense at least one machine state, select a vehicle speed in response to the at least one machine state, and execute a vehicle speed limit algorithm to generate an engine control message;

means for communicating between the electronic transmission controller and an electronic engine controller; and

means for reducing a power output of the engine responsive to communication of the engine control message to the electronic engine controller.

18. The machine of claim 17 including means for storing a vehicle speed limit and data relating vehicle speed to transmission output speed in a memory coupled to the electronic transmission controller;

and

means for executing a gear binding speed limiting algorithm responsive to a predetermined failure.

19. The machine of claim 18 wherein the electronic transmission controller is configured for communication according to an SAE J1939 data bus communication standard.

20. The machine of claim 19 wherein the drive train includes a torque converter;

and

the engine control message is contained in a torque limit data field of a Torque/Speed Control #1 (TSC1) message of the SAE J1939 data bus communication standard.

25. The machine of claim 17 wherein the at least one machine state corresponds to a position of a dump body.

26. The machine of claim 17 wherein the drive train includes an engine;

and

wherein the at least one machine state indicates operation of a power take off powered by said engine.