Patent · US Active

Method for determination of at least a drag torque effective on the input side of an automatic motor vehicle transmission

US9644733B2 · kind B2 · utility

1Cited by

1References

6Claims

0Family size

Assignee

ZF FRIEDRICHSHAFEN AG · DE

Inventors

Marcus Gansohr · Salem, DE
Benjamin M. Berger · Rye Brook, US
Florian Schneider · Obernzenn, DE

Key dates

Filing date	Jun 12, 2014
Grant date	May 9, 2017
Priority date	—
Expiry date	Jun 12, 2034

Classification

Technology area (CPC B)Performing Operations; Transporting
CPC primaryB60W2510/102
WIPO fieldTransport
WIPO sectorMechanical engineering

Abstract

A method of determining at least one drag torque acting on the input side of an automatic transmission, such that prior to the determination a separator clutch located between the transmission and an engine is disengaged. To be able to carry out the determination regardless of the type of transmission concerned, also prior to the determination, the transmission is shifted to neutral and subsequently the drag torque is calculated when the engine is deactivated. For this, a first gradient of a transmission input rotational speed is determined, before an engine rotational speed of the engine falls below the transmission input rotational speed, and a second gradient of the transmission input rotational speed is determined, after the engine rotational speed falls below the transmission input rotational speed. The method is stored as a computer program stored on data carrier of a drive-train control unit of a motor vehicle.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.