Diagnostic and control method for clutches in a vehicle system

Patent metadata

Field	Value
Publication number	US-11719293-B2
Application number	US-202117457234-A
Country	US
Kind code	B2
Filing date	Dec 1, 2021
Priority date	Dec 1, 2021
Publication date	Aug 8, 2023
Grant date	Aug 8, 2023

Abstract

Methods and systems are provided for controlling and diagnosing one or more clutches in a transmission. In one example, a method for operation of a vehicle system is provided that includes at a diagnostic controller or processing unit independent from a driveline controller or processing unit, respectively, determining an engagement state of a clutch in a transmission of the vehicle system, wherein the engagement state is selected from a group of three or more clutch engagement states. The method further includes identifying an unauthorized clutch state based on the engagement state of the clutch and a speed of the vehicle and responsive to the identification of the unauthorized clutch state, operating the vehicle system in a fault state.

First claim

The invention claimed is:

1. A method for operation of a vehicle system, comprising:
at a diagnostic controller or processing unit independent from a driveline controller or processing unit, respectively, determining an engagement state of a first clutch in a transmission of the vehicle system, wherein the engagement state is selected from a group of three or more clutch engagement states;
identifying an unauthorized clutch state based on the engagement state of the first clutch and a speed of the vehicle; and
responsive to the identification of the unauthorized clutch state, operating the vehicle system in a fault state.

2. The method of claim 1 , wherein the three or more clutch engagement states include an engaged state, an intermediate state occurring during a shifting transient, and a disengaged state.

3. The method of claim 2 , wherein:
the engaged state, the intermediate state, and the disengaged state each are delineated by a lower pressure threshold and a higher pressure threshold;
the disengaged state is identified when a clutch pressure is below the lower pressure threshold;
the engaged state is identified when the clutch pressure is above the higher pressure threshold; and
the intermediate state is identified when the clutch pressure is above the lower pressure threshold and below the higher pressure threshold.

4. The method of claim 1 , wherein the engagement state of the first clutch is determined based on a pressure applied to the first clutch and/or a drive current provided to an actuator of the first clutch.

5. The method of claim 1 , wherein identifying the unauthorized clutch state includes:
comparing the engagement state of the first clutch against an engagement state of a second clutch; and
determining that the first clutch and the second clutch are opposite clutches in unauthorized engagement states.

6. The method of claim 5 , wherein the vehicle system is operated in the fault state in response to a duration of the unauthorized clutch state exceeding a fault tolerant time.

7. The method of claim 6 , wherein the fault tolerant time is variable.

8. The method of claim 6 , wherein the vehicle system is operated in the fault state in response to the vehicle speed exceeding a threshold speed.

9. The method of claim 1 , wherein the first clutch is a directional clutch, a gear clutch, or a range clutch.

10. A vehicle system, comprising:
a transmission including a plurality of clutches configured to selectively engage and disengage to shift between a plurality of discrete gear ratios;
a diagnostic controller or processing unit including:
instructions that, when executed, cause the diagnostic controller or processing unit to:
determine an engagement state of each of a plurality of clutches, wherein each of the engagement states are selected from a group of engagement states that include an engaged state, an intermediate state, and a disengaged state; and
operate the vehicle system in a fault state based on a comparison of the engagement states of the plurality of clutches.

11. The vehicle system of claim 10 , wherein the intermediate state is associated with a shifting transient.

12. The vehicle system of claim 10 , wherein the plurality of clutches include one or more range clutches, one or more gear clutches, and one or more directional clutches.

13. The vehicle system of claim 10 , wherein operating the vehicle system in the fault state includes disengaging the plurality of clutches.

14. The vehicle system of claim 10 , wherein the vehicle system is operated in the fault state when a vehicle speed exceeds a threshold speed.

15. The vehicle system of claim 14 , wherein the vehicle system is operated in the fault state when a duration of an unauthorized clutch state exceeds a fault tolerant time.

16. A method for operation of a driveline system, comprising:
at a diagnostic controller independent from a driveline controller, determining a vehicle speed;
determining an engagement state of each of a first clutch and a second clutch in a transmission based on a pressure or current associated with each of the first clutch and the second clutch, wherein the engagement state of each clutch is selected from a group of three or more clutch engagement states that includes an engaged state, an intermediate state, and a disengaged state;
identifying an unauthorized clutch state based on a comparison between the engagement states of the first and second clutches and a set of unauthorized clutch states; and
responsive to the identification of the unauthorized clutch state and the vehicle speed exceeding a threshold speed, operating the first clutch and the second clutch in a fault state.

17. The method of claim 16 , wherein the intermediate state occurs during a shifting transient.

18. The method of claim 16 , wherein the unauthorized clutch state includes an engaged or intermediate state of both of the first and second clutches.

19. The method of claim 18 , wherein the first and second clutches are gear clutches.

20. The method of claim 18 , wherein the first and second clutches are directional clutches or range clutches.

Assignees

• Dana Automotive Systems Group

Inventors

• Deckmyn Peter
• De Buyser Christophe
• Vanstechelman Kris

Classifications

• F16H2061/1208

  with diagnostic check cycles; Monitoring of failures · CPC title

• F16H2061/1224

  Adapting to failures or work around with other constraints, e.g. circumvention by avoiding use of failed parts · CPC title

• F16H59/44

  dependent on machine speed {, e.g. the vehicle speed} (F16H59/46 takes precedence) · CPC title

• F16H61/12

  Detecting malfunction or potential malfunction, e.g. fail safe (in control of hydrostatic gearing F16H61/4192) {; Circumventing or fixing failures} · CPC title

• F16H2061/1276

  the failing part is a friction device, e.g. clutches or brakes · CPC title