Engine idle speed control

Patent metadata

Field	Value
Publication number	US-11846240-B2
Application number	US-202117446105-A
Country	US
Kind code	B2
Filing date	Aug 26, 2021
Priority date	Aug 26, 2021
Publication date	Dec 19, 2023
Grant date	Dec 19, 2023

Abstract

A method and a system for adjusting a base idle speed of an engine are described. In one example, the method reduces engine speed according to output of a sensor that senses mechanical vibrations. Once a vibration level exceeds a threshold, engine speed reduction ceases and the base engine idle speed is adjusted according to a present engine speed.

First claim

The invention claimed is:

1. A method for operating an engine, comprising:
adjusting a base idle speed of the engine in response to an operating state of an active noise cancellation system, where adjusting the base idle speed includes:
progressively reducing a speed of the engine and receiving an output of a vibration sensor or a sound sensor via a controller until the output of the vibration sensor or the sound sensor increases to a first threshold level; and
adjusting the base idle speed of the engine to the speed of the engine where the output of the vibration sensor or the sound sensor is substantially equal to the first threshold level.

2. The method of claim 1 , where the vibration sensor or the sound sensor is in a passenger cabin.

3. The method of claim 1 , where the vibration sensor or the sound sensor is coupled to a vehicle chassis.

4. The method of claim 1 , where the vibration sensor or the sound sensor is contained within a smart phone that communicates with the controller.

5. The method of claim 1 , where the speed is reduced via reducing an amount of air entering the engine.

6. The method of claim 1 , where the speed of the engine is reduced via reducing an amount of fuel delivered to the engine.

7. The method of claim 1 , where the vibration sensor is an accelerometer and where the sound sensor is a microphone, and further comprising:
not adapting an engine idle speed to a present engine idle speed and adapting the engine idle speed to a prior engine idle speed where a sound pressure level measured by the microphone is less than the first threshold level in response to the sound pressure level measured by the microphone being greater than the first threshold level while the active noise cancellation system is reducing audible sounds in a passenger cabin of a vehicle.

8. The method of claim 1 , where progressively reducing the speed of the engine includes only reducing the speed of the engine until the output of the vibration sensor or the sound sensor increases to the first threshold level.

9. A system, comprising:
an engine;
an active noise cancellation system including a microphone; and
a controller including executable instructions stored in non-transitory memory that when executed cause the controller to:
in response to an operating state of the active noise cancellation system, progressively reduce an idle speed of the engine and receive an output of the microphone until the output of the microphone increases to a first threshold level.

10. The system of claim 9 , further comprising additional instructions to adjust the idle speed based on the first threshold level in response to the operating state of the active noise cancellation system being activated, and adjust the idle speed based on a second threshold level in response to the operating state of the active noise cancellation system being inactive.

11. The system of claim 10 , further comprising additional instructions to adjust a base idle speed of the engine to a present speed of the engine in response to a sound pressure level measured by the microphone being substantially equal to the first threshold level while the active noise cancellation system is reducing audible sounds in a passenger cabin of a vehicle.

12. The system of claim 11 , further comprising additional instructions to adjust the base idle speed of the engine to the present speed of the engine in response to the sound pressure level measured by the microphone being substantially equal to a second threshold while the active noise cancellation system is not reducing audible sounds in the passenger cabin of the vehicle.

13. The system of claim 9 , where the active noise cancellation system includes a speaker in a passenger cabin, and further comprising:
not adapting an engine idle speed to a present idle speed and adapting the engine idle speed to a prior idle speed where a sound pressure level measured by the microphone is less than the first threshold level in response to the sound pressure level measured by the microphone being greater than the first threshold level while the active noise cancellation system is reducing audible sounds in the passenger cabin of a vehicle.

14. The system of claim 9 , where the microphone is in a passenger cabin.

15. The system of claim 9 , further comprising a vibration sensor and additional instructions to reduce a speed of the engine while the engine is idling and while a vibration level measured by the vibration sensor is less than third threshold.

16. The system of claim 15 , where the vibration sensor is in a passenger cabin of a vehicle.

17. A method for operating an engine, comprising:
in response to an active noise cancellation request, measuring audible sounds via a first microphone via a controller;
in response to an absence of the active noise cancellation request, measuring audible sounds via the first microphone via the controller;
in response to a sound pressure level determined by the first microphone exceeding a second threshold level in the absence of the active noise cancellation request, not adjusting an engine idle speed;
in response to the sound pressure level determined by the first microphone not exceeding the second threshold level in the absence of the active noise cancellation request, adjusting the engine idle speed; and
in response to the sound pressure level determined by a second microphone being less than a first threshold level in a presence of the active noise cancellation request, adjusting the engine idle speed, where adjusting the engine idle speed includes:
progressively reducing a speed of the engine via the controller while receiving a bandpass filtered output of a first sensor and a bandpass filtered output of a second sensor until the bandpass filtered output of the first sensor is greater than a first threshold or the bandpass filtered output of the second sensor is greater than a third threshold.

18. The method of claim 17 , further comprising adjusting a base idle speed of the engine to the speed of the engine where the bandpass filtered output of the first sensor is substantially equal to the first threshold.

19. The method of claim 17 , further comprising adjusting a base idle speed of the engine to the speed of the engine where the bandpass filtered output of the second sensor is substantially equal to the third threshold.

20. The method of claim 17 , further comprising:
adjusting engine air flow to reduce the speed of the engine; and
progressively reducing the speed of the engine via the controller such that the bandpass filtered output of the first sensor is greater than a second threshold when an active noise cancellation system is inactive.

Assignees

• Ford Global Tech Llc

Inventors

• Shelby Michael
• Leone Thomas
• Cundy Christopher

Classifications

• F02D31/003 Primary

  for idle speed control · CPC title

• F02D31/008 Primary

  for idle speed control · CPC title

• F02D2200/025

  Engine noise, e.g. determined by using an acoustic sensor · CPC title

• F02D41/08

  for idling (F02D41/06, F02D41/16 take precedence) · CPC title

• Y02T10/12

  Improving ICE efficiencies · CPC title