EP 0129652 B1 19870603 - HYDRAULIC CONTROL SYSTEM FOR THE STEERING AND POWER HYDRAULICS OF VEHICLES
Title (en)
HYDRAULIC CONTROL SYSTEM FOR THE STEERING AND POWER HYDRAULICS OF VEHICLES
Publication
Application
Priority
DE 3319533 A 19830528
Abstract (en)
[origin: EP0129652A1] 1. A hydraulic control system for the steering and other hydraulically energized equipment - including a controllable power lift (18, 19, 32) - of a motor vehicle, particularly of a tractor, the system comprising two hydraulic circuits serving to feed pressure fluid to the hydraulically operable devices, each circuit including its respective hydraulic pump (1, 2) and both being interconnectable by actuating a sequence valve (37), in which the hydraulic pump (1) of the first circuit is arranged to feed pressure fluid to a hydraulic power steering device (8) via an element (10) adapted to accord priority to supplying this device, in which any pressure fluid not required for steering is arranged to flow via one or more distributing valves (16) for the other consuming devices to the - subsequent - power lift (19), and in which the second hydraulic circuit's hydraulic pump (2) communicates, if pressure fluid is not required, via the sequence valve (37) with a pressure fluid reservoir (7), characterized in that a duct (50) of the second hydraulic circuit includes at least one distributing valve (52) which serves to feed pressure fluid to the other consuming devices, which is located between the hydraulic pump (2) and the sequence valve (37) and which is provided, like the other distributing valve (16), with a neutral passage, that the outlet of the first mentioned distributing valve's (52) neutral passage is connected via a nonreturn valve (53) to the inlet of the distributing valve (16) of the first hydraulic circuit, that the sequence valve (37) while normally connecting the outlet of the first-mentioned distributing valve's (52) neutral passage with the reservoir (7) closes this by-pass if either the distributing valve (16) of the first hydraulic circuit or a power-lift control valve (20) is actuated, that the power-lift control valve (20) is arranged to be actuated by a pilot valve (32), that the pilot pressure for the control valve (20) is also simultaneously transmitted to the sequence valve (37) so as to urge the latter towards its closing position, and in that the transmission of the pilot pressure to the sequence valve (37) is effected via a flow-inhibiting throttling member (throttling relief valves 44, 45).
IPC 1-7
IPC 8 full level
F15B 11/16 (2006.01); F15B 11/17 (2006.01)
CPC (source: EP)
F15B 11/17 (2013.01); F15B 2211/20576 (2013.01); F15B 2211/30505 (2013.01); F15B 2211/3116 (2013.01); F15B 2211/4053 (2013.01); F15B 2211/41554 (2013.01); F15B 2211/428 (2013.01); F15B 2211/46 (2013.01); F15B 2211/7142 (2013.01); F15B 2211/781 (2013.01)
Designated contracting state (EPC)
AT DE FR GB IT
DOCDB simple family (publication)
EP 0129652 A1 19850102; EP 0129652 B1 19870603; AT E27640 T1 19870615; DE 3319533 A1 19841129; DE 3464083 D1 19870709
DOCDB simple family (application)
EP 84103939 A 19840409; AT 84103939 T 19840409; DE 3319533 A 19830528; DE 3464083 T 19840409