Method for running a drive line

Patent metadata

Field	Value
Publication number	US-9239106-B2
Application number	US-201113039946-A
Country	US
Kind code	B2
Filing date	Mar 3, 2011
Priority date	Mar 10, 2010
Publication date	Jan 19, 2016
Grant date	Jan 19, 2016

Abstract

A method for operating a powertrain of a motor vehicle may comprise: providing a powertrain comprising an automatic transmission arranged between a drive unit and an axle drive, wherein an input shaft of the automatic transmission is connected with the drive unit by means of a controllable clutch and an output shaft is connected with the axle drive, and wherein the powertrain comprises also a gearbox-sided, transient auxiliary drive that is selectively connected for activating or engaging a gearbox-sided connecting point or disconnected for deactivating or disengaging from the connecting point; determining, when the gearbox-sided transient auxiliary output is activated or engaged, a load to be borne at the performance of a gearshift; and specifying, depending on the determined load, whether the gearshift is going to be performed and what synchronous elements of the powertrain are being used to perform the gearshift.

First claim

The invention claimed is:

1. A method for operating a powertrain of a motor vehicle, the method comprising:
operating a powertrain, the powertrain comprises:
an automatic transmission arranged between a drive unit and an axle drive, wherein an input shaft of the automatic transmission is connected with the drive unit by a controllable clutch and an output shaft of the automatic transmission is connected with the axle drive, and
a gearbox-sided auxiliary output that is selectively connected for activating or engaging a gearbox-sided connecting point or disconnected for deactivating or disengaging from the connecting point;

determining, based on a load of the powertrain when the gearbox-sided auxiliary output is activated or engaged, a load to be borne by the powertrain when performing a target gearshift to a target gear;
determining, based on the determined load, a first set of synchronous elements of the powertrain for a first gearshift procedure and a second set of synchronous elements of the powertrain for a second gearshift procedure different from the first gearshift procedure; and
conducting the target gearshift to the target gear based on whether a transmission brake is capable of bearing the determined load when the gearbox-side auxiliary output is engaged;
wherein the target gearshift is conducted through the first gearshift procedure with the first set of synchronous elements when a transmission brake is capable of bearing the determined load and the gearbox-sided auxiliary output is engaged; and
wherein the target gearshift is conducted through the second gearshift procedure with the second set of synchronous elements when the transmission brake is not capable of bearing the determined load.

2. A method according to claim 1 , wherein the determination of the load to be borne depends on at least one of:
a load generated when the gearbox-sided auxiliary output is activated or engaged,
driving conditions, and
a driver's request.

3. A method according to claim 1 , wherein the transmission brake is a synchronous element for performing the first gearshift procedure.

4. A method according to claim 1 , wherein at least one of the drive unit and the clutch is a synchronous element for performing the second gearshift procedure.

5. A method according to claim 4 , wherein the drive unit is a combustion motor connected to the input shaft of the automatic transmission by the clutch, and
conducting the second gearshift procedure comprises:
transferring the automatic transmission to a neutral position; and
opening the clutch,
tuning the combustion motor to a target speed of a target gear to be engaged; and
closing the clutch simultaneously to the tuning of the combustion motor.

6. A method according to claim 4 , wherein the drive unit is a combustion motor connected to the input shaft of the automatic transmission by the clutch, and
conducting the second gearshift procedure comprises:
transferring the automatic transmission to a neutral position,
opening the clutch,
tuning the combustion motor to a current speed of the input shaft,
closing the clutch simultaneously to the tuning of the combustion, and
tuning the combustion motor to a target speed of a target gear of the target gearshift after closing the clutch.

7. A method according to claim 4 , wherein the drive unit is designed as a hybrid drive that comprises a combustion motor connected to the input shaft of the automatic transmission by the clutch, and an electric motor that is downstream drive-connected to the clutch, and
conducting the second gearshift procedure comprises:
transferring the automatic transmission to a neutral position;
opening the clutch, and
tuning the electric motor to a target speed of a target gear of the target gearshift after opening the clutch.

8. A method according to claim 1 , further comprising:
determining to conduct no gearshift when neither the transmission brake of the automatic transmission nor the drive unit nor the clutch is capable of bearing the determined load.

9. A method according to claim 1 , wherein, when the gearbox-sided auxiliary output is activated or engaged, the target gearshift is conducted only if an inclination of the roadway on which the motor vehicle is operated is smaller than an applicable limit value.

Assignees

• Schneider Florian
• Mair Roland
• Zahnradfabrik Friedrichshafen

Inventors

• Schneider Florian
• Mair Roland

Classifications

• B60K17/28

  characterised by arrangement, location, or type of power take-off · CPC title

• B60W10/30

  including control of auxiliary equipment, e.g. air-conditioning compressors or oil pumps · CPC title

• F16H61/0403 Primary

  Synchronisation before shifting · CPC title

• B60W30/1888

  Control of power take off [PTO] · CPC title

• F16H3/093

  with two or more countershafts · CPC title