Adjustable control of power take-off subsystem damping and system thereof

Patent metadata

Field	Value
Publication number	US-9869355-B2
Application number	US-201514712572-A
Country	US
Kind code	B2
Filing date	May 14, 2015
Priority date	Nov 19, 2012
Publication date	Jan 16, 2018
Grant date	Jan 16, 2018

Abstract

The present disclosure provides a method for controlling a power take-off assembly. The method includes providing a drive unit, a transmission having an output, a speed sensor, a controller including a memory unit and a processor, and the power take-off assembly including a clutch and a solenoid. The method also includes storing a first threshold in the memory unit, determining a current input speed of the drive unit with the speed sensor, and comparing the current input speed to the first threshold. The method further includes controlling an amount of hydraulic pressure supplied to the clutch and engaging the clutch.

First claim

The invention claimed is:

1. A method for controlling a power take-off assembly, comprising:
providing a drive unit, a transmission including an output, a speed sensor, a controller including a memory unit and a processor, and the power take-off assembly including a clutch, a first solenoid and a second solenoid;
storing a first threshold in the memory unit;
determining a current input speed of the drive unit with the speed sensor;
comparing the current input speed to the first threshold;
controlling an amount of hydraulic pressure supplied to the clutch; and
engaging the clutch by energizing one of the first solenoid or the second solenoid.

2. The method of claim 1 , wherein the controlling step is performed if the current input speed is less than the first threshold.

3. The method of claim 1 , further comprising:
storing a second threshold in the memory unit of the controller;
determining a load induced on the drive unit; and
comparing the load to the second threshold.

4. The method of claim 3 , wherein the controlling step is performed if the current input speed is less than the first threshold and the load is less than the second threshold.

5. The method of claim 1 , wherein the controlling step comprises energizing one of the first solenoid or the second solenoid based on the comparing step.

6. The method of claim 1 , wherein the controlling step comprises energizing the first solenoid to supply full hydraulic pressure to the clutch.

7. The method of claim 1 , wherein the controlling step comprises energizing the second solenoid to supply partial hydraulic pressure to the clutch.

8. The method of claim 1 , further comprising:
detecting if a signal is received from an operator control switch; and
performing the controlling and engaging steps if there is no detected signal received.

9. The method of claim 1 , further comprising:
energizing one of the first solenoid and the second solenoid; and
de-energizing the other of the first solenoid and the second solenoid.

10. The method of claim 1 , further comprising:
storing a set of instructions in the memory unit of the controller for slipping the clutch;
repeatedly performing the determining and comparing steps; and
executing the set of instructions with the processor so long as the current input speed remains below the first threshold.

11. A vehicle, comprising:
a drive unit for producing torque, the drive unit including an output;
a transmission including an input, a first output, and a second output, wherein the input is coupled to the output of the drive unit;
a controller including a memory unit and a processor, the controller electrically coupled to the transmission; and
a power take-off assembly coupled to the second output, the power take-off assembly including a clutch and a solenoid electrically coupled to the controller;
wherein, a set of instructions is stored in the memory unit of the controller, the set of instructions being executable by the processor to receive a current input speed of the drive unit, compare the current input speed to a first threshold, determine if the current input speed is less than the first threshold, fully energize or de-energize the solenoid, and operably control an amount of hydraulic pressure applied to the clutch.

12. The vehicle of claim 11 , wherein the set of instructions stored in the memory unit are further executable by the processor to receive a load on the drive unit, compare the load to a second threshold, and determine if the load is less than the second threshold.

13. The vehicle of claim 11 , further comprising an operator control switch electrically coupled to the controller, the operator control switch configured to be triggered for enabling and disabling the power take-off assembly;
wherein, the set of instructions stored in the memory unit are further executable by the processor to detect if a signal is received from the operator control switch and operably control the amount of hydraulic pressure applied to the clutch if no signal is detected.

14. The vehicle of claim 11 , wherein the set of instructions stored in the memory unit are further executable by the processor to fully energize the solenoid to apply a maximum amount of hydraulic pressure to the clutch.

15. The vehicle of claim 11 , wherein the set of instructions stored in the memory unit are further executable by the processor to energize a second solenoid to apply a reduced amount of hydraulic pressure to the clutch.

16. The vehicle of claim 11 , wherein the power take-off assembly comprises:
an input shaft;
an output shaft;
a first drive gear rotatably driven by the second output;
a first driven gear rotatably coupled to the input shaft, wherein the first driven gear is rotatably driven by the first drive gear;
a second drive gear rotatably coupled to the input shaft; and
a second driven gear rotatably coupled to the output shaft, wherein the second driven gear is rotatably driven by the second drive gear.

17. Power take-off assembly, comprising:
an input shaft configured to transfer torque to the power take-off assembly from a drive unit;
an output shaft having a coupler on one end;
a hydraulic clutch disposed between the input shaft and the output shaft, the hydraulic clutch having a fully engaged position, a partially engaged position, and a disengaged position;
a first solenoid having an open state where the first solenoid is fluidly coupled to the hydraulic clutch and having a closed state where the first solenoid is not fluidly coupled to the hydraulic clutch; and
a second solenoid having an open state where the second solenoid is fluidly coupled to the hydraulic clutch and having a closed state where the second solenoid is not fluidly coupled to the hydraulic clutch;
wherein, when the hydraulic clutch is in the fully engaged position, the first solenoid is in the open state and the second solenoid is in the closed state.

18. The power take-off assembly of claim 17 , wherein when the hydraulic clutch is in the partially engaged position, the second solenoid is in the open state and the first solenoid is in the closed state.

19. The power take-off assembly of claim 17 , wherein when the hydraulic clutch is in the disengaged position, the first solenoid and the second solenoid are in the closed state.

20. The power take-off assembly of claim 17 , further comprising:
a controller having a memory unit and a processor that is electronically coupled to the first solenoid and the second solenoid, the memory unit storing a threshold value; and
a sensor electronically coupled to the controller and configured to measure the rotational speed of the input shaft;
wherein, the sensor communicates the rotational speed of the input shaft to the controller and the controller compares the rotational speed to the threshold and transitions the hydraulic clutch to either the fully engaged position, the partially engaged position, or the disengaged position based on the comparison.

Assignees

• Allison Transm Inc
• Allison Transm Inc

Inventors

• Pociask Michael B
• Briceno Jorge F

Classifications

• F16D2500/70406

  Pressure · CPC title

• F16D2500/10437

  Power Take Off clutch · CPC title

• F16D2500/70605

  Adaptive correction; Modifying control system parameters, e.g. gains, constants, look-up tables · CPC title

• F16D48/066 Primary

  Control of fluid pressure, e.g. using an accumulator (F16D48/062, F16D48/068 take precedence) · CPC title

• B60W30/1888

  Control of power take off [PTO] · CPC title