System and method for preventing centrifugal clutch lock-ups within a transmission of a work vehicle

Patent metadata

Field	Value
Publication number	US-9618064-B2
Application number	US-201414565912-A
Country	US
Kind code	B2
Filing date	Dec 10, 2014
Priority date	Dec 10, 2014
Publication date	Apr 11, 2017
Grant date	Apr 11, 2017

Abstract

In one aspect, a computer-implemented method for preventing centrifugal clutch lock-ups within a work vehicle transmission may generally include transmitting a signal associated with disengaging a clutch of the transmission, wherein the clutch includes a hydraulic actuator having a pressure relief valve. The method may also include monitoring a pressure of the hydraulic fluid supplied to the actuator relative to a predetermined pressure threshold and monitoring a rotational speed of a clutch can associated with the clutch relative to a predetermined speed threshold, wherein the speed threshold is defined relative to a lock-up speed associated with the clutch can. In addition, the method may include transmitting a lock-up signal associated with limiting the rotational speed of the clutch can and/or providing an indication that a clutch lock-up is likely to occur when the pressure exceeds the pressure threshold and the rotational speed exceeds the speed threshold.

First claim

What is claimed is:

1. A computer-implemented method for preventing centrifugal clutch lock-ups within a transmission of a work vehicle, the method comprising:
controlling, with a computing device, an operation of a clutch control valve so as to initiate disengagement of a clutch of the transmission, the clutch control valve being configured to control a supply of hydraulic fluid to a hydraulic actuator of the clutch, the hydraulic actuator having a pressure relief valve, the pressure relief valve being configured to allow the hydraulic fluid to be evacuated from a piston chamber of the hydraulic actuator when the pressure relief valve is in an opened state;
monitoring, with the computing device, a pressure of the hydraulic fluid supplied to the hydraulic actuator relative to a predetermined pressure threshold;
monitoring, with the computing device, a rotational speed of a clutch can associated with the clutch relative to a predetermined speed threshold, the predetermined speed threshold being defined relative to a lock-up speed associated with the clutch can; and
when the pressure exceeds the predetermined pressure threshold and the rotational speed exceeds the predetermined speed threshold, controlling, with the computing device, an operation of at least one component of the work vehicle so as to limit the rotational speed of the clutch can.

2. The method of claim 1 , wherein the predetermined pressure threshold corresponds to a fluid pressure at which the hydraulic fluid contained within the piston chamber applies a force against a piston of the hydraulic actuator that is substantially equal to a biasing force applied by a clutch spring of the hydraulic actuator.

3. The method of claim 1 , wherein monitoring the pressure of the hydraulic fluid comprises monitoring the pressure using a pressure sensor positioned along a flow path of the hydraulic fluid defined between the hydraulic actuator and the clutch control valve.

4. The method of claim 1 , wherein monitoring the rotational speed of the clutch can comprises determining the rotational speed of the clutch can based on at least one of an output speed of the transmission, an output speed of an engine of the work vehicle, a motor speed of a fluid motor of a hydrostatic power unit of the transmission or an angle of a swashplate of the hydrostatic unit.

5. The method of claim 1 , wherein the predetermined speed threshold corresponds to a speed that is less than the lock-up speed associated with the clutch can.

6. The method of claim 5 , wherein the predetermined speed threshold corresponds to a speed ranging from 99% to 80% of the lock-up speed.

7. The method of claim 1 , wherein controlling the operation of the clutch control valve comprises transmitting a valve command signal to the clutch control valve, the valve command signal being associated with cutting off the supply of hydraulic fluid to the hydraulic actuator.

8. The method of claim 1 . wherein controlling an operation of at least one component of the work vehicle comprises controlling the operation of a component associated with at least one of an engine of the work vehicle or the transmission in a manner that limits or reduces an engine output speed or a transmission output speed of the work vehicle.

9. The method of claim 1 , further comprising controlling an operation of an output device located in a cab of the work vehicle so as to provide at least one of an audible or visual notification to an operator of the work vehicle that a clutch lock-up is likely to occur.

10. The method of claim 1 , wherein the pressure relief valve corresponds to an orifice defined in the clutch can or a piston of the hydraulic actuator.

11. A system for preventing centrifugal clutch lock-ups within a transmission of a work vehicle, the system comprising:
a clutch of the transmission, the clutch including a clutch can and a hydraulic actuator having a piston and defining a piston chamber, the hydraulic actuator further including a pressure relief valve configured to allow hydraulic fluid to be evacuated from the piston chamber when the pressure relief valve is in an opened state;
a clutch control valve configured to control the supply of hydraulic fluid to the hydraulic actuator;
a pressure sensor configured to provide pressure measurements associated with a fluid pressure of the hydraulic fluid supplied to the hydraulic actuator; and
a controller communicatively coupled to the clutch control valve and the pressure sensor, the controller being configured to:
control an operation of the clutch control valve so as to initiate disengagement of the clutch;
monitor the fluid pressure of the hydraulic fluid supplied to the hydraulic actuator relative to a predetermined pressure threshold;
monitor a rotational speed of the clutch can relative to a predetermined speed threshold, the predetermined speed threshold being defined relative to a lock-up speed associated with the clutch can; and
when the pressure exceeds the predetermined pressure threshold and the rotational speed exceeds the predetermined speed threshold, control an operation of at least one component of the work vehicle so as to limit the rotational speed of the clutch can.

12. The system of claim 11 , wherein the predetermined pressure threshold corresponds to a fluid pressure at which the hydraulic fluid contained within the piston chamber applies a force against the piston that is substantially equal to a biasing force applied by a clutch spring of the hydraulic actuator.

13. The system of claim 11 , wherein the controller is configured to indirectly monitor the rotational speed of the clutch can based on at least one of an output speed of the transmission, an output speed of an engine of the work vehicle, a motor speed of a fluid motor of a hydrostatic power unit of the transmission or an angle of a swashplate of the hydrostatic unit.

14. The system of claim 11 , wherein the predetermined speed threshold corresponds to a speed that is less than the lock-up speed associated with the clutch can.

15. The system of claim 14 , wherein the predetermined speed threshold corresponds to a speed ranging from 99% to 80% of the lock-up speed.

16. The system of claim 11 , wherein the controller is configured to control the operation of the clutch control valve by transmitting a valve command signal associated with cutting off the supply of hydraulic fluid to the hydraulic actuator.

17. The system of claim 11 , wherein the controller is configured to limit the rotational speed of the clutch can by controlling a component of at least one of an engine of the work vehicle or the transmission in a manner that limits or reduces an engine output speed or a transmission output speed of the work vehicle.

18. The system of claim 11 , wherein the controller is further configured to control an operation of an output device of the work vehicle so as to provide at least one of an audible or visual notification to an operator of the work vehicle that a clutch lock-up is likely to occur.

19. The system of claim 11 , wherein the pressure relief valve corresponds to an orifice defined in the piston or the clutch can.

20. A computer-implemented method for preventing centrifugal clutch lock-ups within a transmission of a work vehicle, the method comprising:
controlling, with a computing device, an operation of a clutch control valve so as to initiate disengagement of a clutch of the transmission, the clutch control valve being configured to control a supply of hydraulic fluid to a hydraulic actuatio

Assignees

• Cnh Ind America Llc
• Cnh Ind America Llc

Inventors

• Kuros Pawel
• Dix Peter J

Classifications

• F16H61/22

  Locking {of the control input devices} (constructional features of locking or disabling mechanisms F16H63/34) · CPC title

• F16D2500/1027

  Details about the hydraulic valves · CPC title

• F16D2500/3067

  Speed of the engine · CPC title

• F16D2500/30415

  Speed of the input shaft · CPC title

• F16D2500/7101

  Driver alarm · CPC title