Patent Number: 7,134,380

Title: Valve arrangement and hydraulic drive

Abstract: The invention concerns a valve arrangement for controlling a hydraulic drive, the supply and the outflow of the hydraulic drive being separately controllable. It is endeavoured to improve the valve arrangement in such a manner that it is intrinsically tight, at the same time having a relatively simple design. For this purpose, a pump pipe and a tank pipe are connected with a first control valve, the first control valve being connected by separate pipes with a second control valve and a third control valve connected in parallel with the second control valve, the second control valve being connected with a first working connection of the hydraulic drive and the third control valve being connected with a second working connection of the hydraulic drive, backflow preventers for preventing the flow from the hydraulic drive in the direction of the tank being connected in parallel with the second control valve and/or the third control valve.

Inventors: Nielsen; Brian (Soenderborg, DK), Hansen; Poul Erik (Gjern, DK), Andersen; Torben Ole (Aalborg, DK)

Assignee: Sauer-Danfoss ApS

International Classification: F15B 13/04 (20060101)

Expiration Date: 2019-11-14 0:00:00