System for protecting drive train components from excessive engine inertial forces

• US 6,186,925 B1
• Filed: 11/13/1998
• Issued: 02/13/2001
• Est. Priority Date: 11/13/1998
• Status: Expired due to Term

• Current Assignee: Cummins Engine Company Incorporated (Cummins Incorporated)
• Original Assignee: Cummins Engine Company Incorporated (Cummins Incorporated)
• Inventors: Bellinger, Steven M.
• Primary Examiner(s): ESTREMSKY, SHERRY LYNN
• Application Number:
  US09/191,674
• Time in Patent Office: 823 Days
• Field of Search: 477/166, 477/174, 477/175, 477/176, 477/180, 192/103.C
• US Class Current: 477/175
• CPC Class Codes: B60W 10/02 including control of driveline clutches
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/10 including control of change-speed gearings
• CPC Class Codes: B60W 10/11 Stepped gearings
• CPC Class Codes: B60W 30/18 Propelling the vehicle
• CPC Class Codes: B60W 30/1819 Propulsion control with control means using analogue circuits, relays or mechanical links
• CPC Class Codes: F16D 2500/30401 On-off signal indicating the engage or disengaged position of the clutch
• CPC Class Codes: F16D 2500/3109 Vehicle acceleration
• CPC Class Codes: F16D 2500/50296 Limit clutch wear
• CPC Class Codes: F16D 2500/50623 Preventing transmission load change
• CPC Class Codes: F16D 2500/7041 Position
• CPC Class Codes: F16D 48/06 Control by electric or electronic means, e.g. of fluid pressure
• CPC Class Codes: F16D 48/068 using signals from a manually actuated gearshift linkage

Abstract

A system for protecting one or more drivetrain components from excessive inertial torque includes an automated clutch disposed between an internal combustion engine and a transmission coupled thereto, wherein the automated clutch is responsive to computer control. Under conditions wherein driveline acceleration exceeds an acceleration threshold, wherein the acceleration threshold preferably corresponds to the weakest of the drivetrain components, a control computer is operable to actuate the automated clutch to thereby electronically disengage the engine from the transmission, and accordingly protect the various drivetrain components from damage due to excessive engine inertial torque. In an alternate embodiment, a control computer is operable to compute or otherwise estimate engine inertial torque and actuate the automated clutch as just described if/when the engine inertial torque exceeds a torque threshold corresponding to an input torque capacity of one or more of the drivetrain components.

Claims

1. A system for protecting one or more drive train components from excessive engine inertial forces, comprising:

a drive train including an internal combustion engine coupled by a clutch to a number of additional drive train components, said clutch responsive to a disengagement signal to automatically disengage said engine from said number of additional drive train components;

means for determining an acceleration rate of said drive train and producing a acceleration value corresponding thereto; and

a control computer comparing said acceleration value with at least one acceleration threshold corresponding to a maximum acceleration capacity of one of said number of additional drive train components, said control computer producing said disengagement signal if said acceleration value exceeds said at least one acceleration threshold.

2. The system of claim 1 further including a memory unit having said at least one acceleration threshold stored therein.

3. The system of claim 2 further including a service/recalibration tool configured for communication with said control computer, said at least one acceleration threshold programmable within said memory unit via said tool.

4. The system of claim 2 wherein said memory unit includes a number of acceleration thresholds stored therein, each of said number of acceleration thresholds corresponding to a separate one of said number of additional drive train components;

and wherein said control computer is operable to compare said acceleration value with each of said number of acceleration thresholds and produce said disengagement signal if said acceleration value exceeds any one of said number of acceleration thresholds.

5. The system of claim 4 wherein said number of additional drive train components includes a transmission having a number of selectable gear ratios;

and wherein said memory unit further includes acceleration thresholds corresponding to maximum acceleration capacities of at least two of the selectable gear ratios of said transmission.

6. The system of claim 1 further including:

means for sensing vehicle speed and producing a vehicle speed signal corresponding thereto;

and wherein said clutch includes means responsive to manual clutch engagement for producing a clutch manually engaged signal and to manual clutch disengagement for producing a clutch manually disengaged signal;

and wherein said clutch is further responsive to a clutch engagement signal to automatically engage said engine with said number of additional drive train components as long as said manual clutch engagement signal is present;

and wherein said control computer is operable to produce said clutch engagement signal after producing said clutch disengagement signal upon detection of said clutch manually disengaged signal and if said vehicle speed signal indicates a vehicle speed above a vehicle speed threshold.

7. The system of claim 1 further including:

means for sensing vehicle speed and producing a vehicle speed signal corresponding thereto;

and wherein said control computer is responsive to said vehicle speed signal to monitor said acceleration rate of said drive train and produce a clutch engagement signal after producing said clutch disengagement signal if said acceleration rate of said drive train falls below said at least one acceleration threshold, if said vehicle speed signal indicates a vehicle speed value below a vehicle speed threshold, said clutch responsive to said clutch engagement signal to engage said engine with said number of additional drive train components.

8. The system of claim 1 further including:

means for sensing vehicle speed and producing a vehicle speed signal corresponding thereto;

and wherein said control computer is responsive to said vehicle speed signal produce a clutch engagement signal within a predefined time period after producing said clutch disengagement signal if said vehicle speed signal indicates a vehicle speed below a vehicle speed threshold, said manual/automatic clutch responsive to said clutch engagement signal to engage said engine with said number of additional drive train components.

9. The system of claim 1 wherein said control computer is further operable to control and manage operation of said internal combustion engine.

10. The system of claim 1 further including:

an engine control computer operable to control and manage operation of said internal combustion engine; and

a communication link connected between said engine control computer and said control computer;

and wherein said control computer is associated with one of said additional drive train components, said engine control computer receiving said disengagement signal from said control computer via said communication link and providing said disengagement signal to said clutch.

11. The system of claim 10 wherein said communication link is an SAE J1939 data link.

12. In a drive train including an internal combustion engine coupled to a number of additional drive train components, a method of protecting one or more of the number of additional drive train components from excessive engine inertial forces, the method comprising the steps of:

determining an acceleration rate of the drive train;

comparing said acceleration rate with at least one acceleration threshold corresponding to a maximum acceleration capacity of one of said number of additional drive train components; and

automatically disengaging the engine from the number of additional drive train components if said acceleration rate exceeds said at least one acceleration threshold.

13. The method of claim 12 wherein the comparing step further includes comparing said acceleration rate with a number of acceleration thresholds each corresponding to maximum acceleration capacities of separate ones of the number of additional drive train components;

and wherein said disengaging step further includes disengaging the engine from the number of additional drive train components if said acceleration rate exceeds any one of said number of acceleration thresholds.

14. The method of claim 12 further including the steps of:

determining vehicle speed;

re-engaging the engine with the number of additional drive train components if said vehicle speed is below a vehicle speed threshold and if said acceleration rate of said drive train falls below said at least one acceleration threshold.

15. The method of claim 12 further including the steps of:

determining vehicle speed;

re-engaging the engine with the number of additional drive train components if said vehicle speed is below a vehicle speed threshold and after expiration of a predefined time period following automatic disengagement of the engine from the number of additional drive train components.

16. A system for protecting one or more drive train components from excessive engine inertial forces, comprising:

a drive train including an internal combustion engine coupled by a clutch to a number of additional drive train components, said clutch responsive to a disengagement signal to disengage said engine from said number of additional drive train components;

means for determining an acceleration rate of said drive train and producing a acceleration value corresponding thereto; and

a control computer determining a drive train torque based on at least said acceleration value and comparing said drive train torque with at least one torque threshold corresponding to a maximum torque capacity of one of said number of additional drive train components, said control computer producing said disengagement signal if said drive train torque exceeds said at least one torque threshold.

17. The system of claim 16 further including a memory unit having said at least one torque threshold stored therein.

18. The system of claim 17 wherein said memory unit includes a number of torque thresholds stored therein, each of said number of torque thresholds corresponding to a torque capacity of a separate one of said number of additional drive train components;

and wherein said control computer is operable to compare said drive train torque with each of said number of torque thresholds and produce said disengagement signal if said drive train torque exceeds any one of said number of torque thresholds.

19. The system of claim 17 further including a service/recalibration tool configured for communication with said control computer, said at least one torque threshold programmable within said memory unit via said tool.

20. The system of claim 17 wherein said memory unit includes a vehicle mass value stored therein;

and wherein said control computer is operable to determine said drive train torque based further on said vehicle mass value.

21. The system of claim 16 wherein said control computer is further operable to control and manage operation of said internal combustion engine.

22. The system of claim 16 further including:

an engine control computer operable to control and manage operation of said internal combustion engine; and

a communication link connected between said engine control computer and said control computer;

and wherein said control computer is associated with one of said additional drive train components, said engine control computer receiving said disengagement signal from said control computer via said communication link and providing said disengagement signal to said clutch.

23. The system of claim 22 wherein said communication link is an SAE J1939 data link.

24. The system of claim 16 further including means for estimating vehicle mass and producing an estimated vehicle mass value;

and wherein said control computer is operable to determine said drive train torque based further on said estimated vehicle mass value.

25. In a drive train including an internal combustion engine coupled to a number of additional drive train components, a method of protecting one or more of the number of additional drive train components from excessive engine inertial forces, the method comprising the steps of:

determining an acceleration rate of the drive train;

determining a drive train torque based on at least said acceleration rate;

comparing said drive train torque with at least one torque threshold corresponding to a maximum torque capacity of one of said number of additional drive train components; and

automatically disengaging the engine from the number of additional drive train components if said drive train torque exceeds said at least one torque threshold.

26. The method of claim 25 wherein the comparing step further includes comparing said drive train torque with a number of torque thresholds each corresponding to maximum torque capacities of separate ones of the number of additional drive train components;

and wherein said disengaging step further includes disengaging the engine from the number of additional drive train components if said drive train torque exceeds any one of said number of torque thresholds.

27. The method of claim 25 wherein the step of determining an drive train torque further includes determining said drive train torque based on a vehicle mass value.

28. The method of claim 27 further including the step of estimating said vehicle mass value.