Method for operating an automatic gearbox on a motor vehicle

• US 20040266583A1
• Filed: 11/21/2003
• Published: 12/30/2004
• Est. Priority Date: 05/25/2001
• Status: Active Grant

• Current Assignee: ZF Friedrichshafen AG (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Original Assignee: ZF Friedrichshafen AG (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Inventors: Kiefer, Michael, Jauch, Friedemann, Schuler, Franz-Josef, Henneken, Markus, Mauz, Thomas
• Granted Patent: US 7,029,421 B2
• Time in Patent Office: Days
• US Class Current: 477/34
• CPC Class Codes: F16H 2059/003 Detecting or using driving style of a driver, e.g. for adapting shift schedules
• CPC Class Codes: F16H 2059/0239 Up- and down-shift or range or mode selection by repeated movement mechanical step by step selection devices F16H63/14
• CPC Class Codes: F16H 59/0204 for automatic transmissions with means for range selection and manual shifting, e.g. range selector with tiptronic
• CPC Class Codes: F16H 59/48 Inputs being a function of acceleration
• CPC Class Codes: F16H 59/72 dependent on oil characteristics, e.g. temperature, viscosity
• CPC Class Codes: F16H 61/0213 characterised by the method for generating shift signals
• CPC Class Codes: F16H 61/16 Inhibiting or initiating shift during unfavourable conditions, e.g. preventing forward reverse shift at high vehicle speed, preventing engine over speed unintentional control input F16H61/18

Abstract

A method is described for operating an automatic transmission in which a command for changing a current ratio of the automatic transmission is generated when achieving preset operating states of the vehicle automatically or by manual input in a manual shifting mode, the activated manual shifting mode being preferred to an automatic shifting mode. The manual shifting mode is quit when a current vehicle speed is less than a threshold value, or when a longitudinal acceleration of the vehicle is within a defined range, a lateral acceleration is less than a threshold value and a driver type evaluation counter is less than a limiting value.

Claims

1. Method for operating an automatic transmission (3) in which a command to change a current ratio of said automatic transmission (3) when achieving a preset operating state of the vehicle is generated automatically or by manual input in a manual shifting mode, the activated shifting mode being preferred to an automatic shifting mode and the manual shifting mode being quit when a current vehicle speed is less than a threshold value or alternatively the three following criteria are met:

a longitudinal acceleration of the vehicle is within a defined range and

a lateral acceleration of the vehicle is less than a threshold value and

a driver type evaluation counter is less than a limiting value.

2. Method according to claim 1, characterized in that the manual shifting mode is deactivated when no other manual input is detected.

3. Method according to claim 1 or 2, characterized in that during activation of the manual shifting mode by manual input an offset value is added to the driver type evaluation counter.

4. Method according to any one of claims 1 to 3, characterized in that during a manual input in manual shifting mode an offset value is added to the driver type evaluation counter.

5. Method according to any one of claims 1 to 4, characterized in that the driver type evaluation counter is decreased during the activated manual shifting mode without manual input.

6. Method according to any one of claims 1 to 5, characterized in that a manual input occurs when a selector lever (5) is moved in a selector device toa manual gate (7) or an inching push button (22) of said selector device is actuated.

7. Method according to any one of claims 1 to 6, characterized in that during a change to the manual shifting mode an actual ratio of a former shift program of said automatic transmission (3) is taken over and maintained.

8. Method according to any one of claims 1 to 7, characterized in that during a change to the automatic shifting mode, a shift program coordinated with the actual driver type evaluation counter is activated.

9. Method according to any one of claims 1 to 7, characterized in that during a change to the automatic shifting mode a shift program coordinated with the actual driver type evaluation counter is activated.

10. Method according to any one of claims 1 to 9, characterized in that a special shift program active prior to a change to the manual shifting mode is again selected after quitting the manual shifting mode.

11. Method according to any one of claims 1 to 10, characterized in that a change from manual to automatic shifting mode by actuating said selector device (5, 22) can be carried out, there being preferably started, when the manual shifting mode is quit, a time lag after the lapse of which a first ratio change to automatic shifting mode can be implemented.

12. Method according to any one of claims 1 to 12, characterized in that in manual shifting mode an inching shift program is activated in which coordinated gear and converter characteristic lines are stored.

13. Method according to claim 12, characterized in that the inching shift program has a function for detecting a kick-down, a kick-down state being kept maximum for an applicable time.

14. Method according to claim 12 or 13, characterized in that an acoustic, haptic or optical signal is issued when said inching shift program detects an inadmissible a shifting command of the driver.

15. Method according to any one of claims 1 to 14, characterized in that the manual shifting mode is quit when an inadmissibly high temperature of the automatic transmission and/or of the engine is found, there being selected shifting characteristic lines of the automatic shifting mode which lead to lowering of the temperature in question.