Method for controlling an automatic transmission for a motor vehicle

• US 20030139868A1
• Filed: 10/31/2002
• Published: 07/24/2003
• Est. Priority Date: 05/04/2000
• Status: Active Grant

• Current Assignee: ZF Friedrichshafen AG (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Original Assignee: ZF Friedrichshafen AG (Zeppelin - Stiftung der Stadt Friedrichshafen)
• Inventors: Schuler, Franz-Josef, Mauz, Thomas, Herbster, Kai-Uwe, Henneken, Markus, Jauch, Friedmann
• Granted Patent: US 6,801,845 B2
• Time in Patent Office: Days
• US Class Current: 701/51
• CPC Class Codes: B60K 31/042 where at least one electrical quantity is set by the vehicle operator
• CPC Class Codes: B60W 2530/16 Driving resistance
• CPC Class Codes: B60W 2552/15 Road slope, i.e. the inclination of a road segment in the longitudinal direction
• CPC Class Codes: B60W 2556/50 of positioning data, e.g. GPS [Global Positioning System] data
• CPC Class Codes: F16H 2059/663 Road slope
• CPC Class Codes: F16H 2059/666 Determining road conditions by using vehicle location or position, e.g. from global navigation systems [GPS]
• CPC Class Codes: F16H 2061/0227 Shift map selection, i.e. methods for controlling selection between different shift maps, e.g. to initiate switch to a map for up-hill driving
• CPC Class Codes: F16H 59/66 Road conditions, e.g. slope, slippery
• CPC Class Codes: F16H 61/0213 characterised by the method for generating shift signals
• CPC Class Codes: F16H 61/10 Controlling shift hysteresis

Abstract

The invention relates to a method for controlling an automatic transmission for a motor vehicle which is equipped with cruise control. Said method is characterized in that the control of the transmission during cruise control passes into a separate driving programme, which depends on external influences, in particular the inclination of the carriageway. Said driving programme is updated according to the external influences. In the “set” position, the change to the separate driving programme is initiated and in the “restore” position, the transmission control can be adjusted in such a way that the separate driving programme is activated immediately, or only once the control position “set” has been reached.

Claims

1. Method for control of an automatic transmission for a motor vehicle which is equipped with a cruise control wherein upon manual activation by the driver of the cruise control in the state “

set”

a change is made to a driving program for constantly keeping the velocity of the motor vehicle existing at the activation and which is given up, the same as the motor vehicle being automatically decelerated by the driver or accelerated by the driver and thereby passing over to the state “

restore”

characterized in that, when activating the cruise control in the “

set”

state, the driving program is selected from a group of driving programs as function of external influences on the motor vehicle, specially of the road inclination, and as function of a preset driving mode, that upon change of the external inferences, specially of the road inclination, one other driving program is automatically selected from the group of driving programs and that upon deactivation of the cruise control and subsequent activation of the state “

restore”

the transmission control can be adjusted so that the cruise control and therewith the selection of an adequate driving program are to be activated immediately or after reaching the state “

set”

.

2. Method according to claim 1, characterized in that the road inclination is determined via a tractional resistance.

3. Method according to claim 1, characterized in that the road inclination is determined via a gradient sensor.

4. Method according to claim 1, characterized in that the road inclination is determined via a GPS.

5. Method according to one or more of the preceding claims, characterized in that when the cruise control is activated the driving activity calculation runs on line in the background without direct influence upon the selection of the driving program.

6. Method according to one or more of the preceding claims, characterized in that when the cruise control is deactivated, a pre-defined fixed driving program with only one shifting characteristic line is selected.

7. Method according to claim 6, characterized in that as pre-defined fixed driving program is selected the normal driving program closest to the last program selected before deactivation of the cruise control.

8. Method according to claim 6, characterized in that as pre-defined fixed driving program is selected the driving program with superimposed road inclination specification corresponding to the driving activity running on line in the background.

9. Method according to one or more o the preceding claims, characterized in that when activating the cruise control the driver can manually trigger an additional function for automatic setting of a directional velocity, or of an admissible velocity, or of a reduced velocity as function of data fed by the cruise control, specially by a GPS and/or an RDS.