Idle return system and method for an off highway vehicle

Patent metadata

Field	Value
Publication number	US-9759147-B2
Application number	US-201414473442-A
Country	US
Kind code	B2
Filing date	Aug 29, 2014
Priority date	Aug 29, 2014
Publication date	Sep 12, 2017
Grant date	Sep 12, 2017

Abstract

An engine idle control method of an off highway vehicle. The method including the steps of: detecting a static load on the engine; detecting a dynamic load on the engine; determining if the static load is below a predetermined static level; determining if the dynamic load is less than a predetermined range; and engaging an auto-idle feature dependent upon both of the determining steps being true.

First claim

What is claimed is:

1. An off highway vehicle, comprising:
a chassis;
an engine carried by said chassis; and
a controller in communication with said engine, said controller being configured to execute an engine idle control method that includes the steps of:
detecting a static load on the engine;
detecting a dynamic load on the engine;
determining if said static load is below a predetermined static level;
determining if said dynamic load is less than a predetermined range;
engaging an auto-idle feature dependent upon both of said determining steps;
disengaging said auto-idle feature if either of said determining steps are not true; and
returning an engine speed of the engine to correspond to a throttle setting when said disengaging step determines that at least one of the determining steps are not true.

2. The off highway vehicle of claim 1 , wherein said engaging step of said method is not carried out unless service brakes are activated on the vehicle.

3. The off highway vehicle of claim 2 , wherein said service brakes are considered set when a brake enabled idle variable is set.

4. The off highway vehicle of claim 1 , wherein said method further includes the step of delaying said engaging step until a predetermined time has expired from a time in which said static load is below said predetermined static level and said dynamic load is less than said predetermined range.

5. The off highway vehicle of claim 1 , wherein said determining if said dynamic load is less than a predetermined range step includes a substep of ensuring that said dynamic load is less than said predetermined range for a predetermined time period.

6. The off highway vehicle of claim 5 , wherein said predetermined time period is less than one second.

7. The off highway vehicle of claim 6 , wherein said predetermined time period is approximately 250 msec.

8. The off highway vehicle of claim 1 , wherein said method further includes the step of disengaging said auto-idle feature when an interrupting event is detected.

9. The off highway vehicle of claim 8 , wherein said interrupting event is a seat position change by an operator.

10. The off highway vehicle of claim 8 , wherein said interrupting event is one of a change of a throttle setting, a gear selector not being in a neutral selection, and a one touch idle being activated.

11. An engine idle control method of an off highway vehicle, the method comprising the steps of:
detecting a static load on the engine;
detecting a dynamic load on the engine;
determining if said static load is below a predetermined static level;
determining if said dynamic load is less than a predetermined range; and
engaging an auto-idle feature dependent upon both of said determining steps.

12. The method of claim 11 , further comprising the step of disengaging said auto-idle feature if either of said determining steps are not true.

13. The method of claim 12 , wherein said disengaging step includes the step of returning the engine speed to correspond to a throttle setting.

14. The method of claim 12 , further comprising the step of delaying said engaging step until a predetermined time has expired from a time in which said static load is below said predetermined static level and said dynamic load is less than said predetermined range.

15. The method of claim 12 , wherein said determining if said dynamic load is less than a predetermined range step includes a substep of ensuring that said dynamic load is less than said predetermined range for a predetermined time period.

16. The method of claim 15 , wherein said predetermined time period is less than one second.

17. The method of claim 16 , wherein said predetermined time period is approximately 250 msec.

18. The method of claim 11 , further comprising the step of disengaging said auto-idle feature when an interrupting event is detected.

19. The method of claim 18 , wherein said interrupting event is a seat position change by an operator.

20. The method of claim 18 , wherein said interrupting event is one of a change of a throttle setting, a gear selector not being in a neutral selection, and a one touch idle being activated.

Assignees

• Cnh Ind America Llc

Inventors

• Walz Robert
• Chibucos Nicholas S

Classifications

• F02D2041/1411

  using a finite or infinite state machine, automaton or state graph for controlling or modelling · CPC title

• F02D41/083 Primary

  taking into account engine load variation, e.g. air-conditionning · CPC title

• F02D29/04

  peculiar to engines driving pumps · CPC title

• E02F9/2246

  Control of prime movers, e.g. depending on the hydraulic load of work tools · CPC title

• E02F9/2066

  of the type combustion engines · CPC title