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1. (WO2017157606) HYDRAULIC SYSTEM FOR A TRANSMISSION OF A MOTOR VEHICLE

Pub. No.:    WO/2017/157606    International Application No.:    PCT/EP2017/053575
Publication Date: Fri Sep 22 01:59:59 CEST 2017 International Filing Date: Sat Feb 18 00:59:59 CET 2017
IPC: F01M 1/02
F16H 61/00
F15B 11/17
Applicants: ZF FRIEDRICHSHAFEN AG
Inventors: HERRMANN, Markus
SCHMIDT, Thilo
HAUGG, Armin
HABERSTOCK, Alexander
POPP, Christian
Title: HYDRAULIC SYSTEM FOR A TRANSMISSION OF A MOTOR VEHICLE
Abstract:
The invention relates to a hydraulic system (4) for a transmission of a motor vehicle. The hydraulic system comprises a first pump (5) which can be driven by an engine of the motor vehicle, and a second pump (20) which can be driven electrically, wherein the first pump (5) and the second pump (20) are set up in each case solely to deliver hydraulic fluid into a primary system pressure circuit (16) and a secondary system pressure circuit (18) of the hydraulic system (4). The hydraulic system (4) has retaining means (15, 26) which, in the case of a first pump (5) which is not conveying and a second pump (20) which is conveying, are set up to prevent a volumetric flow of hydraulic fluid which is conveyed by the second pump (20) being guided through the first pump (5), or, in the case of a second pump (20) which is not conveying and a first pump (5) which is conveying, are set up to prevent a volumetric flow of hydraulic fluid which is conveyed by the first pump (5) being guided through the second pump (20). Furthermore, the hydraulic system (4) has a regulating lubricating valve (22) which is set up to control a volumetric flow of hydraulic fluid which is conveyed by the second pump (20) into the primary system pressure circuit (16) and into the secondary system pressure circuit (18), in such a way that a provided pressure is set in the primary system pressure circuit (16) and in the secondary system pressure circuit (18).