Supervisory control system to select PTO clutch engagement method based on real-time inertial load estimation

Patent metadata

Field	Value
Publication number	US-10443523-B2
Application number	US-201715403734-A
Country	US
Kind code	B2
Filing date	Jan 11, 2017
Priority date	Jan 11, 2016
Publication date	Oct 15, 2019
Grant date	Oct 15, 2019

Abstract

A method for controlling power takeoff (PTO) clutch engagement includes determining an output clutch speed, adjusting a clutch current at a predetermined rate, estimating an inertial load of a PTO implement and adjusting the clutch current for one or more times at a time interval, and selecting a clutch control algorithm configured for the inertial load of the PTO implement.

First claim

The invention claimed is:

1. A system of a work vehicle, comprising:
a power takeoff (PTO) system comprising:
a PTO clutch comprising a clutch control solenoid valve configured to regulate supply of hydraulic fluid to the PTO clutch and control engagement and disengagement of the PTO clutch based on a clutch current; and
a PTO output shaft coupled to the PTO clutch, wherein the PTO output shaft, in operation, is coupled to and drives a PTO implement; and

a controller comprising a supervisory control system communicatively coupled to the PTO clutch, wherein the supervisory control system comprises a first clutch control logic configured for a first range of inertial loads of the PTO implement and a second clutch control logic configured for a second range of inertial loads of the PTO implement, wherein the supervisory control system, in operation:
determines an output clutch speed of the PTO clutch;
adjusts the clutch current of the PTO clutch at a predetermined rate by at least increasing the clutch current of the PTO clutch at the predetermined rate when the output clutch speed is less than a threshold output clutch speed;
estimates an inertial load of the PTO implement and adjusts the clutch current for one or more times at a time interval;
selects the first clutch control logic when the estimate is within the first range of inertial loads; and
selects the second clutch control logic when the estimate is within the second range of inertial loads.

2. The system of claim 1 , wherein estimating the inertial load of the PTO implement and adjusting the clutch current for the one or more times comprises:
determining a plurality of estimates of the inertial load of the PTO implement; and
adjusting the clutch current after determining each estimate of the plurality of estimates of the inertial load of the PTO implement.

3. The system of claim 2 , wherein estimating the inertial load of the PTO implement and adjusting the clutch current for the one or more times comprises determining a mean of the plurality of estimates of the inertial load of the PTO implement.

4. The system of claim 1 , wherein the output clutch speed is determined based at least on signal received from a sensor communicatively coupled to the PTO output shaft.

5. The system of claim 1 , wherein estimating the inertial load of the PTO implement and adjusting the clutch current for the one or more times comprises:
determining a difference between a measured clutch output shaft speed at a certain time during engagement and a measured clutch output shaft speed at a time of an immediately previous time interval;
dividing the time interval by the difference; and
multiplying a result of dividing the time interval by a clutch torque at the certain time during engagement.

6. The system of claim 1 , wherein the supervisory control system comprises software stored in a memory device of the controller.

7. A tangible, non-transitory, machine-readable-medium, comprising machine-readable instructions to:
determine an output clutch speed of a power takeoff (PTO) clutch of a work vehicle;
adjust a clutch current of the PTO clutch at a predetermined rate;
estimate an inertial load of a PTO implement and adjust the clutch current for one or more times at a time interval by at least:
determining a difference between a measured clutch output shaft speed at a time during engagement and a measured clutch output shaft speed at a time of an immediately previous time interval;
dividing the time interval by the difference; and
multiplying a result of dividing the time interval by a clutch torque at the time during engagement;

select a first clutch control algorithm configured for a first range of inertial loads when the estimate is within the first range of inertial loads; and
select a second clutch control algorithm configured for a second range of inertial loads when the estimate is within the second range of inertial loads.

8. The machine-readable-medium of claim 7 , wherein estimating the inertial load of the PTO implement and adjusting the clutch current for the one or more times comprises:
determining a plurality of estimates of the inertial load of the PTO implement; and
adjusting the clutch current after each estimate of the plurality of estimates of the inertial load of the PTO implement is determined.

9. The machine-readable-medium of claim 8 , wherein estimating the inertial load of the PTO implement and adjusting the clutch current for the one or more times comprises determining a mean of the plurality of estimates of the inertial load of the PTO implement.

10. The machine-readable-medium of claim 8 , wherein estimating the inertial load of the PTO implement and adjusting the clutch current for the one or more times comprises determining a median of the plurality of estimates of the inertial load of the PTO implement.

11. The machine-readable-medium of claim 8 , wherein estimating the inertial load of the PTO implement and adjusting the clutch current for the one or more times comprises determining a maximum of the plurality of estimates of the inertial load of the PTO implement.

12. The machine-readable-medium of claim 8 , comprising machine-readable instructions to select a third clutch control algorithm configured for a third range of inertial loads when the estimate is within the third range of inertial loads.

13. A method for controlling power takeoff (PTO) clutch engagement, comprising:
determining an output clutch speed;
adjusting a clutch current at a predetermined rate;
estimating an inertial load of a PTO implement and adjusting the clutch current for one or more times at a time interval by at least:
increasing the clutch current for the one or more time intervals; and
determining a mean of the plurality of estimates of the inertial load of the PTO implement; and

selecting a clutch control logic of a plurality of clutch control logics based on the estimate of the inertial load of the PTO implement.

14. The method of claim 13 , wherein estimating the inertial load of the PTO implement and adjusting the clutch current for the one or more times comprises:
determining a difference between a measured clutch output shaft speed at a certain time during engagement and a measured clutch output shaft speed at a time of an immediately previous time interval;
dividing the time interval by the difference; and
multiplying a result of dividing the time interval by a clutch torque at the time during engagement.

15. The method of claim 13 , wherein the clutch control logic has an input comprising the inertial load of the PTO implement.

16. The method of claim 13 , wherein selecting the clutch control logic configured for the inertial load of the PTO implement comprises:
selecting a first set of parameters for a clutch control algorithm, such that the clutch control algorithm using the first set of parameters is configured for a first range of inertial loads when the estimate is within the first range of inertial loads; and
selecting a second set of parameters for the clutch control algorithm, such that the clutch control algorithm using the second set of parameters is configured for a second range of inertial loads when the estimate is within the second range of inertial loads.

Assignees

• Cnh Ind America Llc

Inventors

• Vora Kushan
• Guo Haibo
• Hartman Brian Allen

Classifications

• F02D2200/101

  Engine speed · CPC title

• F02D29/02

  peculiar to engines driving vehicles; peculiar to engines driving variable pitch propellers · CPC title

• F02D2041/1409

  using at least a proportional, integral or derivative controller · CPC title

• B60Y2200/221

  Tractors · CPC title

• F16H2059/147

  Transmission input torque, e.g. measured or estimated engine torque · CPC title