| 摘要 |
A hydraulic control arrangement with at least two directional control valves (11, 12) and a flow regulator (17) for controlling, as independently of one another as possible, at least two pressure-medium flows to the servomotors of a stacker truck is proposed, the first directional control valve (11) allocated to the total or residual flow being of short construction. The first directional control valve (11), connected to a residual flow passage (35) from the flow regulator (17) and to an inflow passage (25), lies in a neutral circulation passage (32) downstream of a second directional control valve (12) which is allocated to the constant flow of the flow regulator (17). The outflow side of a second pressure relief valve (52) is connected to the neutral circulation passage (32) between both directional control valves (11, 12) so that the secondary pressure protection, set for a low pressure, only acts during sole actuation of the second directional control valve (12). Although a residual flow passage, passing through the constant-flow directional control valve (12), and troublesome surges in the control sequence during parallel actuation of both directional control valves (11, 12) with interruption of the constant flow take-off are dispensed with, the first directional control valve (11) with seven controlled connections permits a short type of construction. <IMAGE>
|
