Apparatus and method for protecting engine electronic circuitry from thermal damage

• US 6,363,315 B1
• Filed: 07/13/2000
• Issued: 03/26/2002
• Est. Priority Date: 07/13/2000
• Status: Expired due to Fees

• Current Assignee: Caterpillar Incorporated
• Original Assignee: Caterpillar Incorporated
• Inventors: Love, William J., McGee, Brian G.
• Primary Examiner(s): WOLFE JR, WILLIS RAY
• Application Number:
  US09/616,091
• Time in Patent Office: 621 Days
• Field of Search: 701/101, 701/102, 701/103, 701/104, 701/105, 123/41.31, 123/647, 123/478, 123/480, 123/486, 257/467, 257/713, 361/688, 361/704, 361/717, 361/718, 361/719, 361/722
• US Class Current: 701/104
• CPC Class Codes: F01P 2050/30 Circuit boards
• CPC Class Codes: F02D 41/22 Safety or indicating devices for abnormal conditions in air/fuel ratio feedback systems F02D41/1495, in electric control linkage F02D11/107, in purge control systems F02M25/0809
• CPC Class Codes: F02D 41/3005 Details not otherwise provided for
• CPC Class Codes: F02D 41/402 Multiple injections
• CPC Class Codes: H01L 2924/00 Indexing scheme for arrangements or methods for connecting or disconnecting semiconductor or solid-state bodies as covered by H01L24/00
• CPC Class Codes: H01L 2924/0002 Not covered by any one of groups H01L24/00, H01L24/00 and H01L2224/00
• CPC Class Codes: Y02T 10/40 Engine management systems

Abstract

A control system and method for protecting engine electronic circuitry from thermal damage including an electronic controller coupled to the engine, and one or more sensors coupled to the controller for inputting at least one signal indicative of a condition which can be correlated to the temperature of the electronic circuitry. The controller is operable to establish the temperature of the electronic circuitry based upon the at least one sensor input and to output a signal to effectively lower the temperature of the electronic circuitry when the temperature of such circuitry exceeds a predetermined threshold temperature. The sensor inputs to determine or establish a correlation between the input signal and the temperature of the electronic circuitry may include sensing engine speed, sensing the voltage level of the power source providing electrical power to the circuitry, or sensing the temperature of the circuitry directly. The signal outputted by the controller to effectively lower the temperature of the circuitry may include a signal to control the number of fuel shots delivered to the engine during a particular fuel injection event, and/or the firing frequency of the fuel injectors, and/or a signal to restrict engine performance for at least a specified period of time.

Claims

1. A control system for preventing thermal damage to electronic circuitry associated with the operation of an engine, said control system comprising:

an electronic controller coupled to the engine;

at least one signal providing mechanism coupled to said controller for inputting a signal thereto indicative of a condition which can be correlated to the temperature of the electronic circuitry;

said controller being operable to output a signal to effectively lower the temperature of the electronic circuitry when said input signal is indicative of a condition which corresponds to the temperature of the electronic circuitry exceeding a predetermined threshold temperature.

2. The control system as set forth in claim 1 wherein said controller is further operable to discontinue said signal to effectively lower the temperature of the electronic circuitry when said input signal is no longer indicative of a condition which corresponds to the temperature of the electronic circuitry exceeding a predetermined threshold temperature.

3. The control system as set forth in claim 1 wherein said signal outputted by said controller to effectively lower the temperature of the electronic circuitry is a signal to control the number of fuel injection shots delivered to the engine during a particular fuel injection event.

4. The control system as set forth in claim 1 wherein the engine includes a plurality of electronically controlled fuel injectors, said signal outputted by said controller to effectively lower the temperature of the electronic circuitry being a signal to control the firing frequency of said fuel injectors for a predetermined period of time.

5. The control system as set forth in claim 1 wherein said input signal is indicative of engine speed, said controller outputting said signal to effectively lower the temperature of the electronic circuitry when said engine speed exceeds a threshold speed.

6. The control system as set forth in claim 5 wherein said signal providing mechanism includes an engine speed sensor.

7. The control system as set forth in claim 1 wherein said input signal is indicative of the voltage level of the electrical power being supplied to the electronic circuitry, said controller outputting said signal to effectively lower the temperature of the electronic circuitry when said voltage level is below a threshold value.

8. The control system as set forth in claim 7 wherein said signal providing mechanism includes a voltage sensor coupled to a power source providing electrical power to the electronic circuitry.

9. The control system as set forth in claim 1 wherein said input signal is indicative of the temperature of the electronic circuitry, said controller outputting said signal to effectively lower the temperature of the electronic circuitry when said temperature exceeds a predetermined threshold temperature.

10. The control system as set forth in claim 9 wherein said signal providing mechanism is a temperature sensor coupled to the electronic circuitry.

11. The control system as set forth in claim 1 further comprising data storage means coupled to said controller to receive an output signal from said controller, said data storage means being operable to store data indicative of a condition which corresponds to the temperature of the electronic circuitry exceeding a predetermined threshold temperature.

12. The control system as set forth in claim 11 wherein said stored data is retrievable by means of a service tool for use at a later time.

13. The control system as set forth in claim 1 wherein the signal outputted by said controller to effectively lower the temperature of the electronic circuitry includes a signal to a system operable to restrict the operation of the engine.

14. The control system as set forth in claim 13 wherein said signal restricting the operation of the engine is discontinued when the temperature of the electronic circuitry reaches a second predetermined temperature for a specified period of time.

15. A control system for preventing thermal damage to electronic circuitry associated with the operation of an engine, said control system comprising:

an electronic controller coupled to the engine;

one or more sensors coupled to said controller for inputting certain signals thereto representative of certain conditions affecting the operation of the engine;

said controller being operable to establish the temperature of the electronic circuitry based upon at least one of said input signals;

said controller being further operable to output a signal to effectively lower the temperature of the electronic circuitry when said temperature exceeds a predetermine threshold temperature.

16. The control system as set forth in claim 15 wherein at least one of said sensors is an engine speed sensor operable to input a signal to said controller indicative of the speed of the engine, said controller being operable to establish the temperature of the electronic circuitry based upon the signal inputted by said engine speed sensor.

17. The control system as set forth in claim 15 wherein at least one of said sensors is a voltage sensor operable to sense the voltage level of the power source supplying electrical power to the electronic circuitry, said controller being operable to establish the temperature of the electronic circuitry based upon the signal inputted by said voltage sensor.

18. The control system as set forth in claim 15 wherein at least one of said sensors is a temperature sensor operable to sense the temperature of the electronic circuitry, said controller being operable to establish the temperature of the electronic circuitry based upon the signal inputted by said temperature sensor.

19. The control system as set forth in claim 15 wherein said controller is operable to establish the temperature of the electronic circuitry based upon more than one input signal from a plurality of sensors, said controller outputting a signal to effectively lower the temperature of the electronic circuitry based upon a predetermined combination of said input signals.

20. The control system as set forth in claim 19 wherein the engine receives a signal indicative of a plurality of fuel shots during a particular fuel injection event, said signal outputted by said controller to effectively lower the temperature of the circuitry being indicative of restricting the number of fuel shots in said fuel injection event.

21. The control system as set forth in claim 19 wherein said signal outputted by said controller to effectively lower the temperature of the circuitry is indicative of restricting the performance of said engine.

22. A method for preventing thermal damage to electronic circuitry associated with the operation of an engine, the method comprising the steps of:

(a) sensing a condition associated with the control of the operation of the engine;

(b) establishing the temperature associated with the electronic circuitry based upon said sensed condition;

(c) comparing the established temperature of the electronic circuitry with a threshold temperature; and

(d) outputting a signal to effectively lower the temperature of the electronic circuitry when the established temperature exceeds the threshold temperature.

23. The method as set forth in claim 22 further comprising the step of establishing said threshold temperature such that continued operation of said circuitry above said threshold temperature may result in thermal damage to said circuitry.

24. The method as set forth in claim 22 wherein said sensed condition is the speed of the engine.

25. The method as set forth in claim 22 wherein said sensed condition is the voltage level of the power source which delivers electrical power to the electronic circuitry.

26. The method as set forth in claim 22 wherein said sensed condition is the temperature of the electronic circuitry.

27. The method as set forth in claim 22 including the steps of:

outputting a signal to a data storage means to store data indicative of said sensed condition when the established temperature of the electronic circuitry exceeds the threshold temperature.

28. The method as set forth in claim 22 including the step of:

outputting a signal restricting the operation of the engine when the established temperature of the electronic circuitry exceeds the threshold temperature.

29. The method as set forth in claim 28 including the step of:

discontinuing said signal to restrict the operation of the engine when the temperature of the electronic circuitry drops below a second predetermined threshold temperature for a predetermined period of time.

30. The method as set forth in claim 22 wherein said signal to effectively lower the temperature of the electronic controller is a signal to control the number of fuel injection firings to the engine during a particular fuel injection event.

31. A method for preventing thermal damage to electronic circuitry associated with a fuel system, the electronic circuitry being adapted to control one or more fuel injection devices, the method comprising the steps of:

establishing a temperature of the electronic circuitry; and

generating a fuel injection signal based upon said established temperature.

32. The method as set forth in claim 31 further comprising sensing an engine speed and an engine load, and wherein the step of establishing a temperature of the electronic circuitry is based upon at least one of said sensed engine speed and engine load.

33. The method as set forth in claim 31 wherein the step of generating said fuel injection signal further includes sensing an engine speed and an engine load and generating said fuel injection signal in response to said sensed engine speed and engine load.

34. The method as set forth in claim 31 further comprising the step of dynamically modifying said fuel injection signal in response to said established temperature.

35. A control system for preventing thermal damage to electronic circuitry associated with a fuel system of an engine, the electronic circuitry being adapted to control one or more fuel injection devices and generating fuel injection signals to control the operation of the engine, said control system comprising:

an electronic controller coupled to the fuel injection devices;

at least one sensor coupled to said controller for inputting certain signals thereto representative of certain conditions affecting the operation of the engine;

said controller being operable to establish a temperature for the electronic circuitry based upon at least one of said input signals;

said controller being further operable to output a fuel injection signal in response to said established temperature.

36. The control system as set forth in claim 35 wherein said certain input signals are indicative of the speed and load of the engine, said controller being further operable to output said fuel injection signal in response to said engine speed and engine load.

37. The control system as set forth in claim 35 wherein said certain input signals are indicative of the speed and load of the engine, said controller being further operable to establish the temperature for the electronic circuitry based upon at least one of said engine speed and engine load.