Method of monitoring a truck engine and for controlling the temperature of a truck sleeper unit

• US 5,317,998 A
• Filed: 09/01/1993
• Issued: 06/07/1994
• Est. Priority Date: 09/01/1993
• Status: Expired

• Current Assignee: Trans TRON Limited Incorporated
• Original Assignee: Thermo King Corporation (Trane Technologies plc)
• Inventors: Hanson, Jay L., Sutton, Loran W., Knauff, Donald G.
• Primary Examiner(s): Yuen, Henry C.
• Application Number:
  US08/114,401
• Time in Patent Office: 279 Days
• Field of Search: 123/179.4, 123/179.3, 307/10.6, 307/10.7
• US Class Current: 123/179.4
• CPC Class Codes: F02N 11/0803 characterised by means for initiating engine start or stop F02N11/0814 takes precedence

Abstract

A method of automatically starting and stopping an engine of a truck to conserve fuel while maintaining the engine in a ready-to-start condition, and while controlling the temperature of a truck sleeper unit. The method includes the steps of selecting predetermined system parameters via a password accessible interactive program, providing a first switch for selecting an automatic engine start-stop operating mode, providing a second switch for selecting an automatic temperature control mode for the truck sleeper unit, and providing safety apparatus which indicates when the truck engine may be safely operated in the automatic engine start-stop operating mode. The method further includes the step of overriding the ignition switch control of the engine in response to a predetermined condition when the first switch selects the automatic operating mode and the safety apparatus indicates the truck engine may be safely operated in the automatic operating mode. The engine is started and stopped automatically while the ignition switch control of the engine is being overridden by the overriding step, to maintain the engine in a ready-to-start condition, regardless of the selection of the second switch, and additionally controlling the temperature of the sleeper unit, when the second switching means selects automatic temperature control. The overriding step is terminated in response to a predetermined condition, restoring ignition switch control of the engine, and preventing automatic re-starting of the engine while the ignition switch is in control of the engine.

Claims

1. A method of automatically starting and stopping an engine of a truck having an ignition switch which includes on and off positions for controlling starting a stopping of the engine, a battery having ignition switch controlled electrical loads, and a sleeper unit, to conserve fuel while providing temperature control of the sleeper unit, and maintaining the truck engine in a ready-to-start condition, comprising the steps of:

selecting predetermined system parameters via a password accessible interactive program,

providing first switch means for selecting an automatic engine start-stop operating mode,

providing second switch means for selecting an automatic temperature control mode for the truck sleeper unit,

providing safety means which indicates when the truck engine may be safely operated in the automatic engine start-stop operating mode,

overriding the ignition switch control of the engine in response to a predetermined condition when the first switch means selects the automatic operating mode and the safety means indicates the truck engine may be safely operated in the automatic operating mode,

starting and stopping the engine automatically while the ignition switch control of the engine is being overridden by the overriding step, to maintain the engine in a ready-to-start condition, regardless of the selection of the second switch means,

starting and stopping the engine automatically while the ignition switch control of the engine is being overridden by the overriding step, to maintain the engine in a ready-to-start condition, and to control the temperature of the sleeper unit, when the second switching means selects automatic temperature control,

terminating the overriding step in response to a predetermined condition, restoring ignition switch control of the engine,

and preventing automatic re-starting of the engine while the ignition switch is in control of the engine.

2. The method of claim 1 wherein the step of overriding the ignition switch includes the step of disconnecting the ignition switch controlled electrical loads from the battery.

3. The method of claim 1 wherein the step of overriding the ignition switch overrides the ignition switch regardless of the position of the ignition switch.

4. The method of claim 3 including the steps of:

enabling temperature control of the sleeper unit when the ignition switch is in the on position,

and disabling temperature control of the sleeper unit when the ignition switch is in the off position.

5. The method of claim 1 wherein the step of overriding the ignition switch is additionally responsive to the position of the ignition switch, overriding the ignition switch only when the ignition switch is in the on position.

6. The method of claim 1 including the step of enabling stopping of the engine by the ignition switch immediately after the step of terminating the overriding step.

7. The method of claim 1 including the step of delaying stopping of the engine by the ignition switch for a predetermined period of time after the step of terminating the overriding step.

8. The method of claim 1 wherein the step of overriding ignition switch control of the engine in response to a predetermined condition includes the step of enabling the overriding step, and initiating a timing period when the step of overriding ignition switch control is enabled, with the predetermined condition which initiates the overriding step being the expiration of the timing period.

9. The method of claim 1 wherein the step of overriding ignition switch control of the engine in response to a predetermined condition includes the step of determining if the engine is running, with the predetermined condition being a finding that the engine is running.

10. The method of claim 1 wherein the predetermined condition which initiates the termination of the overriding step is a change in the first switching means to non-selection of the automatic operating mode.

11. The method of claim 1 wherein the step of selecting predetermined system parameters includes the steps of:

determining if the engine is an electronic fuel injected engine,

determining the number of control relays used for engine control when the engine is an electronic fuel injected engine,

storing a predetermined parameter of the engine for a predetermined relay of an electronic fuel injected engine,

starting the engine when it is stopped in response to predetermined conditions,

and using the stored parameter of the engine in the step of starting the engine.

12. The method of claim 1 wherein the step of selecting predetermined system parameters includes the steps of:

calibrating the measurement of engine speed (RPM) of the engine,

said calibrating step including the steps of running the engine at a predetermined RPM, and storing an indication that the truck is running at the predetermined RPM,

starting the engine when it is stopped, in response to predetermined conditions,

and using calibrated RPM measurements of engine speed during the step of starting the engine.

13. The method of claim 1 wherein the step of selecting predetermined system parameters includes the steps of:

initializing battery voltage measurement,

said initializing step including the step of providing an offset value by which a measured battery voltage is to be modified,

starting, running and stopping the engine in response to predetermined conditions,

measuring the battery voltage in response to predetermined conditions during the steps of starting, running and stopping the engine,

modifying the battery measurements with the offset value,

and using the modified battery measurements in the steps of starting, running, and stopping the engine.

14. The method of claim 1 wherein the step of selecting predetermined system parameters includes the step of selecting a dead band value about a selected set point temperature which will initiate starting and stopping of the engine, for controlling the temperature of the truck sleeper unit.

15. The method of claim 14 wherein the step of selecting predetermined system parameters includes the step of selecting upper and lower ambient temperature limits, and including the steps of:

measuring ambient temperature,

comparing the measurement of ambient temperature with the selected upper and lower ambient temperature limits,

and operating the engine continuously while the comparison step indicates that the measured ambient temperature is outside the selected upper and lower limits.

16. The method of claim 1 wherein the step of electing predetermined system parameters includes the step of selecting a dead band value about a selected set point temperature which will initiate starting and stopping of the engine for controlling the temperature of the truck sleeper unit, and including the steps of:

measuring the running time of the engine when running to drive the temperature of the sleeper unit to a dead band value,

and modifying the selected dead band value to predetermined smaller value when the measured running time exceeds a predetermined value.

17. The method of claim 16 including the step of resetting the dead band value to the selected value after a predetermined period of time.

18. The method of claim 1 wherein the step of controlling the temperature of the sleeper unit includes the steps of starting and stopping the engine to maintain the temperature of the sleeper unit within a predetermined dead band range of a selected set point temperature, measuring engine off time, and running the engine continuously for a predetermined period of time when a measured engine off time is less than a predetermined value.

19. The method of claim 1 wherein the step of selecting predetermined system parameters includes the step of selecting a dead band value about a selected set point temperature which will initiate starting and stopping of the engine according to predetermined cooling and heating control algorithms, and including the steps of:

manually selecting one of heat and cool conditioning modes,

manually selecting a set point temperature,

measuring ambient temperature,

comparing the measurement of ambient temperature with the set point temperature,

using the control algorithm associated with the manually selected conditioning mode, when the manually selected conditioning mode is consistent with the comparison of ambient temperature with the set point temperature,

and using the control algorithm which is not associated with the manually selected conditioning mode, when the manually selected conditioning mode is not consistent with the comparison of ambient temperature with the set point temperature.

20. The method of claim 1 wherein the step of controlling the temperature of the sleeper unit includes the steps of providing a sleeper unit temperature sensor for determining the temperature of the sleeper unit, and detecting when the sleeper unit temperature sensor has been placed outside the sleeper unit in an attempt to operate the engine continuously, with said detecting step including the steps of:

detecting when the temperature difference between the ambient temperature and the temperature reported by the sleeper unit temperature sensor is less than a predetermined value,

determining the length of time the detecting step finds that the detected temperature difference is less than the predetermined value,

and operating the engine in a predetermined on-off time pattern when the determining step finds the detected temperature difference is less than the predetermined value for a predetermined period of time.

21. The method of claim 20 including the step of selecting a set point temperature, and wherein the step of detecting when the sleeper unit temperature sensor has been placed outside the sleeper unit in an attempt to operate the engine continuously further includes the steps of:

determining if the selected set point temperature is within a predetermined normal comfort temperature range,

and deciding that the temperature sensor is properly located within the sleeper unit when the determining step finds that the selected set point temperature is within the predetermined normal comfort temperature range.

22. The method of claim 1 the step of controlling the temperature of the sleeper unit includes the steps of:

operating a sleeper unit fan off the battery while the engine is off,

measuring the battery voltage while the sleeper unit fan is operated with the engine off,

restarting the engine when the battery voltage drops to a predetermined value within a predetermined period of time,

and, when the engine is restarted due to low battery voltage, the step of de-energizing the sleeper unit fan during predetermined subsequent engine off cycles.

23. The method of claim 22 wherein the predetermined subsequent engine off cycles during which the sleeper unit fan is de-energized are those which occur within a predetermined period of time after an engine start due to low battery voltage.

24. The method of claim 1 wherein the step of controlling the temperature of the sleeper unit includes the steps of:

operating a sleeper unit fan while the engine is operative,

determining when an engine start is for the purpose of providing heat to the sleeper unit,

and delaying the step of operating the sleeper unit fan for a predetermined period of time following an engine start to provide heat to the sleeper unit.

25. A method of automatically starting and stopping an engine of a truck having an ignition switch which includes on and off positions for controlling starting a stopping of the engine, a battery having ignition switch controlled electrical loads, and a sleeper unit, to conserve fuel while providing temperature control of the sleeper unit, and maintaining the truck engine in a ready-to-start condition, comprising the steps of:

determining if the engine is an electronic fuel injected engine,

determining the number of control relays used for engine control when the engine is an electronic fuel injected engine,

storing a predetermined parameter of the engine for a predetermined relay of an electronic fuel injected engine,

starting the engine when it is stopped in response to predetermined conditions,

and using the stored parameter of the engine in the step of starting the engine.

26. A method of automatically starting and stopping an engine of a truck having an ignition switch which includes on and off positions for controlling starting a stopping of the engine, a battery having ignition switch controlled electrical loads, and a sleeper unit, to conserve fuel while providing temperature control of the sleeper unit, and maintaining the truck engine in a ready-to-start condition, comprising the steps of:

calibrating the measurement of engine speed (RPM) of the engine,

said calibrating step including the steps of running the engine at a predetermined RPM, and storing an indication that the truck is running at the predetermined RPM,

starting the engine when it is stopped, in response to predetermined conditions,

and using calibrated RPM measurements of engine speed during the step of starting the engine.

27. A method of automatically starting and stopping an engine of a truck having an ignition switch which includes on and off positions for controlling starting a stopping of the engine, a battery having ignition switch controlled electrical loads, and a sleeper unit, to conserve fuel while providing temperature control of the sleeper unit, and maintaining the truck engine in a ready-to-start condition, comprising the steps of:

initializing battery voltage measurement,

said initializing step including the step of providing an offset value by which a measured battery voltage is to be modified,

starting, running and stopping the engine in response to predetermined conditions,

measuring the battery voltage in response to predetermined conditions during the steps of starting, running and stopping the engine,

modifying the battery measurements with the offset value,

and using the modified battery measurements in the steps of starting, running, and stopping the engine.

28. A method of automatically starting and stopping an engine of a truck having an ignition switch which includes on and off positions for controlling starting a stopping of the engine, a battery having ignition switch controlled electrical loads, and a sleeper unit, to conserve fuel while providing temperature control of the sleeper unit, and maintaining the truck engine in a ready-to-start condition, comprising the steps of:

selecting a dead band value about a selected set point temperature which will initiate starting and stopping of the engine, for controlling the temperature of the truck sleeper unit,

selecting upper and lower ambient temperature limits,

measuring ambient temperature,

comparing the measurement of ambient temperature with the selected upper and lower ambient temperature limits,

and operating the engine continuously, without regard to the selected dead band value, while the comparison step indicates that the measured ambient temperature is outside the selected upper and lower limits.

29. A method of automatically starting and stopping an engine of a truck having an ignition switch which includes on and off positions for controlling starting a stopping of the engine, a battery having ignition switch controlled electrical loads, and a sleeper unit, to conserve fuel while providing temperature control of the sleeper unit, and maintaining the truck engine in a ready-to-start condition, comprising the steps of:

selecting a dead band value about a selected set point temperature which will initiate starting and stopping of the engine for controlling the temperature of the truck sleeper unit,

measuring the running time of the engine when running to drive the temperature of the sleeper unit to a dead band value,

and modifying the selected dead band value to predetermined smaller value when the measured running time exceeds a predetermined value.

30. The method of claim 29 including the step of resetting the dead band value to the selected value after a predetermined period of time.

31. A method of automatically starting and stopping an engine of a truck having an ignition switch which includes on and off positions for controlling starting a stopping of the engine, a battery having ignition switch controlled electrical loads, and a sleeper unit, to conserve fuel while providing temperature control of the sleeper unit, and maintaining the truck engine in a ready-to-start condition, comprising the steps of:

starting and stopping the engine to maintain the temperature of the sleeper unit within a predetermined dead band range of a selected set point temperature,

measuring engine off time,

and running the engine continuously for a predetermined period of time, without regard to the dead band range, when a measured engine off time is less than a predetermined value.

32. A method of automatically starting and stopping an engine of a truck having an ignition switch which includes on and off positions for controlling starting a stopping of the engine, a battery having ignition switch controlled electrical loads, and a sleeper unit, to conserve fuel while providing temperature control of the sleeper unit, and maintaining the truck engine in a ready-to-start condition, comprising the steps of:

selecting a dead band value about a selected set point temperature which will initiate starting and stopping of the engine according to predetermined cooling and heating control algorithms,

selecting one of heat and cool conditioning modes,

selecting a set point temperature,

measuring ambient temperature,

comparing the measurement of ambient temperature with the set point temperature,

using the control algorithm associated with the manually selected conditioning mode, when the manually selected conditioning mode is consistent with the comparison of ambient temperature with the set point temperature,

and using the control algorithm which is not associated with the manually selected conditioning mode, when the manually selected conditioning mode is not consistent with the comparison of ambient temperature with the set point temperature.

33. A method of automatically starting and stopping an engine of a truck having an ignition switch which includes on and off positions for controlling starting a stopping of the engine, a battery having ignition switch controlled electrical loads, and a sleeper unit having a sleeper unit temperature sensor for determining the temperature of the sleeper unit, to conserve fuel while providing temperature control of the sleeper unit, and maintaining the truck engine in a ready-to-start condition, with the step of controlling the temperature of the sleeper unit comprising the steps of:

detecting when the sleeper unit temperature sensor has been placed outside the sleeper unit in an attempt to operate the engine continuously,

said detecting step including the steps of;

detecting when the temperature difference between the ambient temperature and the temperature reported by the sleeper unit temperature sensor is less than a predetermined value,

determining the length of time the detecting step finds that the detected temperature difference is less than the predetermined value,

and operating the engine in a predetermined on-off time pattern when the determining step finds the detected temperature difference is less than the predetermined value for a predetermined period of time.

34. The method of claim 33 including the step of selecting a set point temperature, and wherein the step of detecting when the sleeper unit temperature sensor has been placed outside the sleeper unit in an attempt to operate the engine continuously further includes the steps of:

determining if the selected set point temperature is within a predetermined normal comfort temperature range,

and deciding that the temperature sensor is properly located within the sleeper unit when the determining step finds that the selected set point temperature is within the predetermined normal comfort temperature range.

35. A method of automatically starting and stopping an engine of a truck having an ignition switch which includes on and off positions for controlling starting a stopping of the engine, a battery having ignition switch controlled electrical loads, and a sleeper unit, to conserve fuel while providing temperature control of the sleeper unit, and maintaining the truck engine in a ready-to-start condition, comprising the steps of:

operating a sleeper unit fan off the battery while the engine is off,

measuring the battery voltage while the sleeper unit fan is operated with the engine off,

restarting the engine when the battery voltage drops to a predetermined value within a predetermined period of time,

and, when the engine is restarted due to low battery voltage, the step of de-energizing the sleeper unit fan during predetermined subsequent engine off cycles.

36. The method of claim 35 wherein the predetermined subsequent engine off cycles during which the sleeper unit fan is de-energized are those which occur within a predetermined period of time after an engine start due to low battery voltage.