Methods and system for engine braking

Patent metadata

Field	Value
Publication number	US-11192537-B2
Application number	US-201816218387-A
Country	US
Kind code	B2
Filing date	Dec 12, 2018
Priority date	Dec 12, 2018
Publication date	Dec 7, 2021
Grant date	Dec 7, 2021

Abstract

Systems and methods for operating a hybrid powertrain or driveline that includes an engine and an integrated starter/generator are described. In one example, rotation of an automatically stopped engine may be inhibited when engine braking is requested so that the engine may not be rotated without providing a desired outcome.

First claim

The invention claimed is:

1. A powertrain operating method, comprising:
via a controller, inhibiting rotation of an engine that has stopped rotating during conditions when engine braking is desired, except when input is received to the controller via a human/machine interface; and
rotating the engine that has stopped rotating and initiating engine braking in response to the indication to permit engine braking.

2. The method of claim 1 , where the input is moving of a shifter lever.

3. The method of claim 2 , where the shifter lever is moved from a position of a higher gear to a position of a lower gear.

4. The method of claim 1 , where inhibiting rotation of the engine includes not allowing a starter to rotate the engine.

5. The method of claim 1 , where inhibiting rotation of the engine includes not allowing a driveline disconnect clutch to fully or partially close.

6. The method of claim 1 , where inhibiting rotation of the engine includes not allowing a belt driven integrated starter/generator to rotate the engine.

7. The method of claim 1 , where the engine that has stopped rotating has been automatically stopped rotating.

8. A powertrain operating method, comprising:
requesting engine braking via a controller while an integrated starter/generator (ISG) lacks capacity to provide a desired level of driveline braking;
receiving input via a human/machine interface that indicates a request for engine braking; and
starting rotation of an engine that is not rotating via a controller in response to the requested engine braking and receiving input via the human/machine interface.

9. The method of claim 8 , where the input is adjustment of a position of a gear selector.

10. The method of claim 8 , where the input is an adjustment of a powertrain operating mode.

11. The method of claim 10 , where the adjustment of the powertrain operating mode includes entering a hill descent mode.

12. The method of claim 8 , where the engine is rotated via a starter.

13. The method of claim 8 , further comprising inhibiting starting rotation of the engine in response to a lack of a human performing the particular act and the requested engine braking.

14. A system, comprising:
an engine;
an integrated starter/generator (ISG) selectively coupled to the engine via a driveline disconnect clutch; and
a controller including executable instructions stored in non-transitory memory to rotate the engine from a non-rotating state in response to an engine braking request and an input received from a human, and not rotating the engine from the non-rotating state in response to the engine braking request and an absence of the input received from the human.

15. The system of claim 14 , where the input is an adjustment of a state of a gear shift selector.

16. The system of claim 14 , where the input is an adjustment of a state of a driveline mode selector.

17. The system of claim 14 , further comprising additional instructions to automatically stop the engine in the non-rotating state.

18. The system of claim 14 , further comprising additional instructions to rotate the engine at a rotational speed of the ISG in response to the engine braking request and the input received from the human.

19. The system of claim 14 , further comprising additional instructions to provide driveline braking via the ISG in response to a driveline braking request.

20. The system of claim 19 , further comprising additional instructions to generate the engine braking request via the driveline braking request.

Assignees

• Ford Global Tech Llc

Inventors

• Burt Andrew E
• Lee Minku
• Dewalt Joshua

Classifications

• F16D61/00

  Brakes with means for making the energy absorbed available for use (F16D57/00 takes precedence) · CPC title

• B60T1/10 Primary

  by utilising wheel movement for accumulating energy, e.g. driving air compressors · CPC title

• B60T8/171

  Detecting parameters used in the regulation; Measuring values used in the regulation · CPC title

• F02D29/02 Primary

  peculiar to engines driving vehicles; peculiar to engines driving variable pitch propellers · CPC title

• B60W2555/20

  Ambient conditions, e.g. wind or rain · CPC title