Patent Number: 8,814,750

Title: Method and device for controlling a creep mode of a vehicle comprising a hybrid drive

Abstract: The invention relates to a method for controlling a creep mode of a vehicle comprising a hybrid drive (1), a drive train (2) which essentially comprises an internal combustion engine (3), an electric machine (5), a gear-shift element (4) arranged between the internal combustion engine (3) and the electric machine (5), a transmission (7) and a power take-off (26). The aim of the invention is to allow an efficient creep mode which is substantially temporally unlimited and reliable and wherein an electrical energy storage device (14) is used as little as possible. The method according to the invention is characterized in that primarily the gear-shift element (4) is used when the internal combustion engine (3) is running and secondarily, depending on a monitoring of defined operation parameters of the gear-shift element (4) and/or of variables relevant for the creep mode, the electric machine (5) is used to implement the creep mode. A device for carrying out the method comprises control and monitoring means (21, 22, 25, 27) which are used for producing a creep torque, taking into consideration an admissible load of the gear-shift element (4), primarily by operating the gear-shift element (4) in a slip mode and secondarily by operating the electric machine (5) in a creep mode.

Inventors: Kaltenbach; Johannes (Friedrichshafen, DE), Wallner; Stefan (Mattsee, AT)

Assignee: ZF Friedrichshafen AG

International Classification: B60W 10/02 (20060101)

Expiration Date: 8/26/12018