Pump Overspeed Protection Method And Machine Using Same

• US 20120310489A1
• Filed: 05/31/2011
• Published: 12/06/2012
• Est. Priority Date: 05/31/2011
• Status: Active Grant

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Hague, Michael Evan, Marathe, Sameer, Wei, Zhiyong, Marquette, Matthew Stephen
• Granted Patent: US 8,738,241 B2
• Time in Patent Office: Days
• US Class Current: 701/50
• CPC Class Codes: B60W 10/026 of lock-up clutches
• CPC Class Codes: B60W 10/30 including control of auxiliary equipment, e.g. air-conditioning compressors or oil pumps
• CPC Class Codes: B60W 2510/1015 Input shaft speed, e.g. turbine speed
• CPC Class Codes: B60W 2510/107 Temperature
• CPC Class Codes: B60W 30/1846 Preventing of breakage of drive line components, e.g. parts of the gearing
• CPC Class Codes: E02F 9/2079 Control of mechanical transmission for hydrostatic transmission or hydraulic torque converter E02F9/2253
• CPC Class Codes: E02F 9/2246 Control of prime movers, e.g. depending on the hydraulic load of work tools
• CPC Class Codes: E02F 9/226 Safety arrangements, e.g. hydraulic driven fans, preventing cavitation, leakage, overheating
• CPC Class Codes: E02F 9/2292 Systems with two or more pumps
• CPC Class Codes: E02F 9/2296 Systems with a variable displacement pump
• CPC Class Codes: F04B 49/02 Stopping, starting, unloading or idling control
• CPC Class Codes: F04B 49/103 Responsive to speed
• CPC Class Codes: F15B 20/00 Safety arrangements for fluid actuator systems; Applications of safety devices in fluid actuator systems; Emergency measures for fluid actuator systems
• CPC Class Codes: F15B 21/087 Control strategy, e.g. with block diagram

Abstract

A machine having a pump overspeed protection system operating thereon includes an internal combustion engine, a plurality of ground engaging elements, and a drivetrain coupling the internal combustion engine and the ground engaging elements. The drivetrain includes a torque converter having a locked configuration and an unlocked configuration. The machine also includes a plurality of pumps driven by the internal combustion engine. An electronic control is in communication with the internal combustion engine, the torque converter, and the plurality of pumps. The electronic controller is configured to determine a pump speed of a first pump of the plurality of pumps, initiate a first action of a hierarchy of pump overspeed protection actions if the pump speed exceeds a first speed threshold, initiate a second action of the hierarchy of pump overspeed protection actions if the pump speed exceeds a second speed threshold, initiate a third action of the hierarchy of pump overspeed protection actions if the pump speed exceeds a third speed threshold, and monitor a condition of a component altered by at least one of the hierarchy of pump overspeed protection actions. At least one of the hierarchy of pump overspeed protection actions includes increasing a displacement of at least one of the plurality of pumps and at least another of the hierarchy of pump overspeed protection actions includes moving the torque converter from the locked configuration to the unlocked configuration.

Claims

1. A machine having a pump overspeed protection system operating thereon, comprising:

an internal combustion engine;

a plurality of ground engaging elements;

a drivetrain coupling the internal combustion engine and the ground engaging elements, wherein the drivetrain includes a torque converter having a locked configuration and an unlocked configuration;

a plurality of pumps driven by the internal combustion engine; and

an electronic controller in communication with the internal combustion engine, the torque converter, and the plurality of pumps, wherein the electronic controller is configured to determine a pump speed of a first pump of the plurality of pumps, initiate a first action of a hierarchy of pump overspeed protection actions if the pump speed exceeds a first speed threshold, initiate a second action of the hierarchy of pump overspeed protection actions if the pump speed exceeds a second speed threshold, initiate a third action of the hierarchy of pump overspeed protection actions if the pump speed exceeds a third speed threshold, and monitor a condition of a component altered by at least one of the hierarchy of pump overspeed protection actions;

wherein at least one of the hierarchy of pump overspeed protection actions includes increasing a displacement of at least one of the plurality of pumps and at least another of the hierarchy of pump overspeed protection actions includes moving the torque converter from the locked configuration to the unlocked configuration.

2. The machine of claim 1, wherein the first action includes a first pump control action, the second action includes a second pump control action, and the third action includes a torque converter control action.

3. The machine of claim 1, wherein the plurality of pumps includes a fan pump, and the first action includes increasing a displacement of the fan pump.

4. The machine of claim 3, further including a temperature sensor positioned to detect a hydraulic fluid temperature, wherein the electronic controller is configured to monitor the hydraulic fluid temperature and operate the fan pump at an unaltered displacement if the hydraulic fluid temperature is below an overcooled threshold.

5. The machine of claim 3, wherein the plurality of pumps includes an implement pump, and the second action includes increasing a displacement of the implement pump.

6. The machine of claim 5, further including a temperature sensor positioned to detect a hydraulic fluid temperature, wherein the electronic controller is configured to monitor the hydraulic fluid temperature and operate the implement pump at an unaltered displacement if the hydraulic fluid temperature is above an overheated threshold.

7. The machine of claim 6, wherein the electronic controller is further configured to:

determine if an operator command condition associated with the implement pump is true or false; and

operate the implement pump at the unaltered displacement if the operator command condition is true.

8. The machine of claim 5, wherein the third action includes moving the torque converter from the locked configuration to the unlocked configuration.

9. The machine of claim 5, further including a temperature sensor positioned to detect a hydraulic fluid temperature, wherein the electronic controller is further configured to move the torque converter from a locked configuration to the unlocked configuration if the pump speed exceeds the second speed threshold and the hydraulic fluid temperature exceeds a fluid temperature threshold for a predetermined period of time.

10. The machine of claim 1, further including an operator display, wherein the electronic controller is further configured to display an operator message on the operator display corresponding to a performance of at least one of the hierarchy of pump overspeed protection actions.

11. A pump overspeed protection method configured for operation on a machine, the machine including an internal combustion engine, a plurality of ground engaging elements, a drivetrain coupling the internal combustion engine and the ground engaging elements, wherein the drivetrain includes a torque converter having a locked configuration and an unlocked configuration, a plurality of pumps driven by the internal combustion engine, and an electronic controller, the method comprising the steps of:

electronically determining a pump speed of a first pump of the plurality of pumps using the electronic controller;

electronically initiating a first action of a hierarchy of pump overspeed protection actions if the pump speed exceeds a first speed threshold using the electronic controller;

electronically initiating a second action of the hierarchy of pump overspeed protection actions if the pump speed exceeds a second speed threshold using the electronic controller;

electronically initiating a third action of the hierarchy of pump overspeed protection actions if the pump speed exceeds a third speed threshold using the electronic controller; and

electronically monitoring a condition of a component altered by at least one of the hierarchy of pump overspeed protection actions using the electronic controller;

wherein at least one of the hierarchy of pump overspeed protection actions includes increasing a displacement of at least one of the plurality of pumps and at least another of the hierarchy of pump overspeed protection actions includes moving the torque converter from the locked configuration to the unlocked configuration.

12. The pump overspeed protection method of claim 11, wherein the first electronically initiating step includes electronically initiating a first pump control action, the second electronically initiating step includes electronically initiating a second pump control action, and the third electronically initiating step includes electronically initiating a torque converter control action.

13. The pump overspeed protection method of claim 11, further including increasing a displacement of a fan pump in response to the step of electronically initiating the first action.

14. The pump overspeed protection method of claim 13, wherein the electronically monitoring step includes:

electronically monitoring a hydraulic fluid temperature; and

operating the fan pump at an unaltered displacement if the hydraulic fluid temperature is below an overcooled threshold.

15. The pump overspeed protection method of claim 13, further including increasing a displacement of an implement pump in response to the step of electronically initiating the second action.

16. The pump overspeed protection method of claim 15, wherein the electronically monitoring step includes:

electronically monitoring a hydraulic fluid temperature; and

operating the implement pump at an unaltered displacement if the hydraulic fluid temperature is above an overheated threshold.

17. The pump overspeed protection method of claim 16, further including:

determining if an operator command condition associated with the implement pump is true or false; and

operating the implement pump at the unaltered displacement if the operator command condition is true.

18. The pump overspeed protection method of claim 15, further including moving the torque converter from the locked configuration to the unlocked configuration in response to the step of electronically initiating the third action.

19. The pump overspeed protection method of claim 15, further including:

electronically monitoring a hydraulic fluid temperature; and

moving the torque converter from the locked configuration to the unlocked configuration if the pump speed exceeds the second speed threshold and the hydraulic fluid temperature exceeds a fluid temperature threshold for a predetermined period of time.

20. A machine having a pump overspeed protection system operating thereon, comprising:

an internal combustion engine;

a plurality of ground engaging elements;

a drivetrain coupling the internal combustion engine and the ground engaging elements, wherein the drivetrain includes a torque converter having a locked configuration and an unlocked configuration;

a plurality of pumps driven by the internal combustion engine; and

an electronic controller in communication with the internal combustion engine, the torque converter, and the plurality of pumps, wherein the electronic controller is configured to determine a pump speed of a first pump of the plurality of pumps, increase a displacement of a fan pump if the pump speed exceeds a first speed threshold, increase a displacement of an implement pump if the pump speed exceeds a second speed threshold, and move the torque converter from the locked configuration to the unlocked configuration if the pump speed exceeds a third speed threshold.