Transmission internal PTO clutch and method of control

• US 10,071,720 B2
• Filed: 02/26/2016
• Issued: 09/11/2018
• Est. Priority Date: 02/24/2016
• Status: Active Grant

• Current Assignee: Allison Transmission Incorporated (Allison Transmission Holdings Incorporated)
• Original Assignee: Allison Transmission Incorporated (Allison Transmission Holdings Incorporated)
• Inventors: Foster, Michael, Burchett, Douglas
• Primary Examiner(s): Holmes, Justin
• Application Number:
  US15/054,548
• Publication Number:
  US 20170240159A1
• Time in Patent Office: 928 Days
• Field of Search: None
• CPC Class Codes: B60K 17/02 characterised by arrangement, location, or kind of clutch
• CPC Class Codes: B60K 17/28 characterised by arrangement, location, or type of power take-off
• CPC Class Codes: B60K 25/06 from the transmission power take-off transmissions having power-take-off B60K17/28
• CPC Class Codes: B60W 10/06 including control of combustion engines
• CPC Class Codes: B60W 10/30 including control of auxiliary equipment, e.g. air-conditioning compressors or oil pumps
• CPC Class Codes: B60W 2510/0216 Clutch engagement rate
• CPC Class Codes: B60W 2510/081 Speed
• CPC Class Codes: B60W 2510/107 Temperature
• CPC Class Codes: B60W 2510/30 Auxiliary equipments
• CPC Class Codes: B60W 2540/215 Selection or confirmation of options
• CPC Class Codes: B60W 2710/022 Clutch actuator position
• CPC Class Codes: B60W 2710/0644 Engine speed
• CPC Class Codes: B60Y 2300/1888 Control of power take off [PTO]
• CPC Class Codes: B60Y 2400/795 Power take off
• CPC Class Codes: F16D 13/52 Clutches with multiple lamellae ; Clutches in which three or more axially moveable members are fixed alternately to the shafts to be coupled and are pressed from one side towards an axially-located member F16D13/385 takes precedence
• CPC Class Codes: F16D 25/0638 with more than two discs, e.g. multiple lamellae
• CPC Class Codes: F16D 25/12 Details not specific to one of the before-mentioned types
• CPC Class Codes: F16D 2500/1026 Hydraulic
• CPC Class Codes: F16D 2500/10437 Power Take Off clutch
• CPC Class Codes: F16D 2500/106 Engine
• CPC Class Codes: F16D 2500/3024 : Pressure
• CPC Class Codes: F16D 2500/3067 : Speed of the engine
• CPC Class Codes: F16D 2500/308 : from the transmission
• CPC Class Codes: F16D 2500/30825 : Speed of the output shaft
• CPC Class Codes: F16D 2500/314 : from the user
• CPC Class Codes: F16D 48/066 : Control of fluid pressure, e.g. using an accumulator F16D48/062, F16D48/068 take precedence
• CPC Class Codes: F16H 2200/0004 : comprising a power take off shaft
• CPC Class Codes: F16H 63/46 : Signals to a clutch outside the gearbox

Abstract

A method of selectively controlling a power take-off (PTO) assembly includes positioning a clutch assembly radially between a shaft and a PTO gear, operably controlling the clutch assembly with a controller, and selectively engaging the clutch assembly with the controller. The controller monitors signals received from a plurality of sensors and compares the monitored signals with respective signal thresholds. The clutch assembly is engaged when the compared monitored signals are within the signal thresholds.

Claims

1. A method of selectively controlling a power take-off (PTO) assembly, comprising:

positioning a clutch assembly radially between a shaft and a PTO gear;

operably controlling the clutch assembly with a controller;

selectively engaging the clutch assembly with the controller;

wherein the selectively engaging the clutch assembly step comprises;

monitoring, by the controller, signals received from a plurality of sensors;

comparing, by the controller, the monitored signals with respective signal thresholds; and

engaging the clutch assembly when the compared monitored signals are within the signal thresholds;

further wherein, the monitoring signals received from the plurality of sensors step comprises monitoring, by the controller, an engine speed sensor, a user input sensor, and a PTO output speed sensor.

2. The method of claim 1, further wherein the monitoring signals received from the plurality of sensors step comprises monitoring, by the controller, a transmission range sensor, a vehicle speed sensor, a code sensor, a transmission temperature sensor, a vehicle grade sensor, and a line pressure sensor.

3. The method of claim 1, further comprising:

comparing, by the controller, a user input signal generated by the user input to a user input threshold;

wherein, when the user input signal is within the user input threshold, the PTO clutch assembly is engaged;

wherein, when the user input signal is not within the user input threshold, the PTO clutch assembly is not engaged.

4. The method of claim 1, further comprising comparing, by the controller, an engine speed indicated by the engine speed sensor to a PTO speed indicated by the PTO output speed sensor when the clutch assembly is in the engaged position, wherein the controller selectively disengages the clutch when the PTO speed is not within a threshold range relative to the engine speed.

5. The method of claim 1, further wherein the controller does not engage the clutch assembly when a vehicle speed sensor indicates the vehicle speed within a vehicle speed range.

6. A method of controlling a power take-off (PTO) assembly of a transmission, comprising:

providing a user input, an engine, the transmission including a shaft, a hydraulic system, and fluid within the hydraulic system having a line pressure, a controller including a memory unit and a processor, and the PTO assembly including a PTO gear, a PTO output sensor, and a clutch assembly positioned between the PTO gear and the shaft;

determining, by the controller, when a user input has been received;

comparing, by the controller, the line pressure of the fluid to a pressure threshold stored in the memory after the user input has been received;

engaging the clutch assembly, by the controller, when the line pressure is above the pressure threshold;

detecting PTO speed with the PTO output sensor; and

comparing, by the controller, an engine speed of the engine to the PTO speed when the clutch assembly is engaged;

wherein, if a difference between engine speed and PTO speed is not within a predefined speed threshold value, the controller increases the line pressure.

7. The method of claim 6, further comprising increasing engine speed if the line pressure is below the pressure threshold.

8. The method of claim 6, wherein the engaging the clutch assembly step comprises opening a valve of the transmission.

9. The method of claim 6, further wherein the controller compares the line pressure to a second pressure threshold stored in the memory, wherein when the line pressure is greater than the second pressure threshold, the controller modulates the valve in the transmission until the line pressure is less than the second pressure threshold.

10. The method of claim 6, further comprising increasing the engine speed, by the controller, when clutch assembly is in the engaged position and the PTO speed is less than a PTO threshold.

11. The method of claim 6, further wherein:

the controller compares the engine speed to an engine speed threshold stored in the memory of the controller; and

the controller disengages the clutch assembly if the monitored engine speed is greater than the engine speed threshold.

12. A method for controlling a power take-off (PTO) assembly of a transmission, comprising:

providing a controller, a user input, a pressure sensor, a valve, a shaft speed sensor, and the PTO assembly including a PTO gear, a PTO speed sensor and a clutch assembly disposed radially between the PTO gear and a shaft of the transmission;

receiving, with the controller, a command from the user input indicating a desired engagement of the clutch assembly;

comparing a line pressure detected by the pressure sensor to a pressure threshold stored in the controller;

controlling the valve, with the controller, to restrict the clutch assembly from engaging the PTO gear when the line pressure is less than the pressure threshold;

comparing a PTO speed measured by the PTO speed sensor to a shaft speed measured by the shaft speed sensor with the controller when the clutch assembly is in an engaged position; and

disengaging the clutch, with the controller, when the comparing a PTO speed step indicates the PTO speed is not substantially the same as the shaft speed.

13. The method for controlling a clutch assembly of claim 12, further comprising controlling, with the controller, an input speed and increasing the input speed when the line pressure is less than the pressure threshold and the input speed is less than an input speed threshold.

14. The method of controlling a clutch assembly of claim 12, further comprising increasing the line pressure when the shaft speed is greater than the PTO speed.

15. The method of controlling a clutch assembly of claim 12, further comprising reducing the line pressure when the line pressure is above a second pressure threshold.

16. The method of controlling a clutch assembly of claim 12, further comprising restricting the clutch assembly from engaging unless a transmission range selector is within a transmission range threshold.

17. The method of controlling a clutch assembly of claim 12, further comprising:

providing a vehicle grade sensor that communicates the grade of the vehicle to the controller; and

restricting the clutch assembly from engaging when a vehicle grade sensor value is not within a vehicle grade threshold.

18. The method of controlling a clutch assembly of claim 12, further comprising:

monitoring a transmission temperature;

providing an instantaneous full line pressure to engage the clutch assembly when the transmission temperature satisfies a temperature threshold; and

providing a gradual increase to line pressure to engage the clutch assembly when the transmission temperatures does not satisfy the temperature threshold.

19. The method of controlling a clutch assembly of claim 12, further comprising:

monitoring an outrigger; and

engaging the clutch assembly only when the outrigger is in an extended position.

20. A method of selectively controlling a power take-off (PTO) assembly, comprising:

positioning a clutch assembly radially between a shaft and a PTO gear;

operably controlling the clutch assembly with a controller;

selectively engaging the clutch assembly with the controller;

wherein the selectively engaging the clutch assembly step comprises;

monitoring, by the controller, signals received from a plurality of sensors;

comparing, by the controller, the monitored signals with respective signal thresholds; and

engaging the clutch assembly when the compared monitored signals are within the signal thresholds;

further wherein, the controller does not engage the clutch assembly when a vehicle speed sensor indicates the vehicle speed is within a vehicle speed range.