Control system for use on construction equipment

• US 6,535,807 B2
• Filed: 07/16/2001
• Issued: 03/18/2003
• Est. Priority Date: 07/16/2001
• Status: Expired due to Fees

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Janson, Brett J., Wulfert, Wayne J., Christensen, Steven V., Stone, Rob E.
• Primary Examiner(s): Nguyen, Tan Q.
• Assistant Examiner(s): Tran, Dalena
• Application Number:
  US09/906,380
• Publication Number:
  US 20030014170A1
• Time in Patent Office: 610 Days
• Field of Search: 701/50, 701/124, 172/2, 172/6, 340/686.1, 340/611, 340/626, 340/685, 372/34, 379/02, 177/141, 177/136, 747/311, 747/321
• US Class Current: 701/50
• CPC Class Codes: E02F 9/2029 Controlling the position of implements in function of its load, e.g. modifying the attitude of implements in accordance to vehicle speed control for hydraulic or pneumatic drives E02F9/2203, E02F9/2221 and E02F9/2253 take precedence
• CPC Class Codes: E02F 9/2066 of the type combustion engines
• CPC Class Codes: E02F 9/267 Diagnosing or detecting failure of vehicles

Abstract

A control system for use in connection with control systems on construction equipment includes an electronic control module that records pressure sensor signals of a hydraulic pressure sensor and responsively determines whether the pressure sensor has failed.

Claims

1. A method for determining the operation of a pressure sensor on construction equipment having implements and a powertrain powered by an engine, said method including:

determining when said implements are in a low load condition and responsively measuring a first output of said pressure sensor;

determining when said implements are in a high load condition and responsively measuring a second output of said pressure sensor; and

evaluating the operation of the pressure sensor in response to said first output and said second output.

2. The method according to claim 1, including:

determining a difference between said first output and said second output and incrementing a fault counter in response to said difference being less than a predetermined value.

3. The method according to claim 2, including:

registering a fault code in response to said fault counter exceeding a predetermined value.

4. The method according to claim 1, wherein said step of determining that the implement is in a low load condition includes inputting an operator implement control input.

5. The method according to claim 4, wherein said implement control input includes an implement lift lever control.

6. The method according to claim 5, wherein said implement control input includes an implement tilt lever control.

7. The method according to claim 4, wherein said implement control input includes an ECM directed command.

8. The method according to claim 4, wherein said step of determining that the implement is in a low load condition includes determining an engine speed.

9. The method according to claim 8, wherein said implement control input includes an implement lift lever control.

10. The method according to claim 1, wherein said step of determining that the implement is in a low load condition includes inputting an engine speed signal.

11. A method for determining the operation of a pressure sensor associated with a hydraulic system powering an implement on construction equipment, said construction equipment having a powertrain, said powertrain and said hydraulic system being powered by an engine, said method including:

determining when said implement is in a low load condition and responsively measuring a first output of said pressure sensor;

determining when said implement is in a high load condition and responsively measuring a second output of said pressure sensor;

determining that the pressure sensor is inoperative in response to said first output and said second output; and

limiting power output of said engine in response to said step of determining that the pressure sensor is inoperative.

12. A control system for use with construction equipment, said construction equipment having a hydraulically powered implement and a powertrain, and an engine providing power to said hydraulically powered implement and said powertrain, said control system including:

a pump associated with the engine, said pump providing hydraulic pressure for use by said implement;

a pressure sensor associated with an output of said pump, said pressure sensor producing a signal indicative of the pressure of the hydraulic fluid;

an implement control, said control producing a signal indicative of a desired motion of said implement;

an engine speed sensor, said engine speed sensor producing a signal indicative of the rotational velocity of the engine;

an electronic control module connected with said pressure sensor, said implement control and said engine speed sensor, wherein said electronic control module reads a low load pressure signal from said pressure sensor, and a high load pressure signal from said pressure sensor and produces and fault code as a function of said low load pressure signal and said high load pressure signal.

13. The control system of claim 12, wherein said electronic control module produces said fault code as a function of a difference between said high load pressure signal and said low load pressure signal exceeding a predetermined value.

14. The control system of claim 13, wherein said electronic control module produces said fault code in response to said difference between said high load pressure signal and said low load pressure signal exceeding said predetermined value a predetermined number of times.

15. The control system according to claim 14, wherein said electronic control module limits the engine power in response to said fault code.