Abstract:
An arrangement for controlling remotely hydraulic valves located between a variable displacement pump and a load supplied from the pump. The valve has a control slider the position of which is indicated through a signal generator on the slider. Control levers are also coupled to the slider and the position of these levers is indicated through another signal generator coupled to the levers. A control unit connected to the signal generators, compares their signal outputs and actuates electrohydraulic positioning means for controlling the pump flow as a function of the deflection of the control levers.
Abstract:
The apparatus comprises an operation control unit, and a plurality of consumer control units with consumer conduits for a plurality of hydraulic motors. The consumer conduits are individually controlled by spring-biased consumer valves which are, respectively, actuated under control of single-stroke electromagnets. The operation control units include a springbiased control valve actuated by another single-stroke electromagnet to connect inlet means and outlet means, respectively, through a connecting conduit with all consumer control units.
Abstract:
A spring-biased regulating valve directs fluid from a pump at a constant pressure to a first outlet up to a certain amount required by a consumer apparatus, and directs at the same time excess fluid to a second outlet. When the pressure in the first outlet rises above the desired constant value, a biased control valve responds to the pressure increase and causes the regulating valve to direct all the fluid from the pump to the second outlet until the pressure in the first outlet has again its desired constant value.
Abstract:
An arrangement for controlling directional valves electrohydraulically. The valve is connected between a constant pump and a load which is actuated through fluid under pressure from the pump. The directional valve has a control slide to which a signal transducer is secured to give a signal indicative of the position of the control slide. Control levers are also arranged with the control slide and have signal transducers for indicating the deflection of the control lever from a neutral position. A control circuit is connected to the signal transducers for comparing their signal outputs, and to actuate electrohydraulic positioning member on the control slide for controlling the position of the control slide dependent upon the position of the control lever. A switching valve controls the neutral fluid flow from the pump to the load as a function of the position of the control lever.