Patent · US Active

Hydraulic control device for an automatic transmission

US10060525B2 · kind B2 · utility

0Cited by

6References

20Claims

0Family size

Assignee

ZF FRIEDRICHSHAFEN AG · DE

Inventors

Markus Herrmann · Scheidegg, DE
Thilo Schmidt · Meckenbeuren, DE
Bernd Allgaier · Kreßbronn, DE

Key dates

Filing date	Sep 17, 2014
Grant date	Aug 28, 2018
Priority date	—
Expiry date	Feb 7, 2035

Classification

Technology area (CPC F)Mechanical Engineering; Lighting; Heating
CPC primaryF16H2061/026
WIPO fieldMechanical elements
WIPO sectorMechanical engineering

Abstract

When the stop valve is in a first shifting position, a torque-transferring shift element is sealed tight against the rest of a hydraulic system by a stop valve, such that the actuating pressure enclosed in the shift element remains essentially constant or does not decrease. The stop valve is formed and arranged in the hydraulic system such that the stop valve is held in the first shifting position by the force of a barrier pressure generated by the pump, and, upon a standstill of the pump or falling below a certain value of the pressure generated by the pump, the stop valve is automatically displaceable at least through the action of the trapped shift element pressure into a second shifting position, in which the respective shift element is connected to the rest of the hydraulic system and the shift element is open.

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