The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 27, 2007
Filed:
Oct. 26, 2005
Gunther Petrzik, St. Georgen, DE;
Gunther Petrzik, St. Georgen, DE;
GETRAG Getriebe-und Zahnradfabrik Hermann Hagenmeyer GmbH & Cie KG, Untergruppernback, DE;
Abstract
A hydraulic circuit for the control of a double clutch transmission which has two transmission groups, each with an isolating clutch and with a plurality of shift clutches for the engagement and disengagement of gear steps, the hydraulic circuit having for each transmission group a specific hydraulic branch connected to a pump in each case via a safety valve, and each hydraulic branch having in each case a clutch control valve for controlling the assigned isolating clutch and at least one shift control valve for controlling the assigned shift clutches. Here, the safety valves are designed in each case as proportional pressure regulating valves.