摘要:
Modular directional valve with two or more crossing elements (E1.. En) fed by a variable displacement (PA), negative control or load sensing pump. A pressure regulator (5) is placed in the entry side and only on the bypass line and upstream of the first element (E1..En). In the single drive, it makes the flow rate to the utility independent of the load and allows setting a maximum flow rate at the end of the stroke; in multiple drives, it ensures that the sum of the required flow rates is independent of the loads.
摘要:
In one aspect, a system for controlling the supply of hydraulic fluid to an implement of a work vehicle may generally include a pump, a control valve coupled to the pump and first and second fluid lines provided in flow communication with output ports of the control valve. The system may also include a pressure control valve provided in flow communication with the second fluid line that is configured to regulate a fluid pressure of the hydraulic fluid being supplied to a hydraulic cylinder of the implement. Additionally, the system may include a bypass fluid line configured to provide a flow path for hydraulic fluid between the pump and the second fluid line that is independent of the control valve and a load sensing line configured to provide an indication of the fluid pressure of the hydraulic fluid being supplied to the hydraulic cylinder.
摘要:
Die Erfindung betrifft eine Ventileinheit zur ausschließlichen hydraulischen Betätigung des Verriegelungsmittels eines mechanischen Schnellwechslers für Anbaugeräte einer Baumaschine, wobei die Ventileinheit einen Speisedruckanschluss zum Anlegen des Speisedrucks, einen ersten Ventileinheitausgang zum Anschluss einer Entriegelungsdruckleitung, einen zweiten Ventileinheitausgang zum Anschluss einer Verriegelungsdruckleitung, wenigstens eine Entlastung zum Tank und wenigstens zwei schaltbare Wegeventile umfasst, wobei der Speidesdruckanschluss mit dem zweiten Ventileinheitausgang über eine Reihenschaltung der wenigstens zwei schaltbaren Wegeventile verbunden bzw. verschaltbar ist.
摘要:
A method and system providing a pressurized fluid includes a pump (114) having a pump inlet (113) and a pump outlet (115), the pump (114) to provide a fluid flow, a bypass path (119) to direct the fluid flow from the pump outlet (115) to the pump inlet (113), a load path (121) having a load path pressure, the load path (121) including: a fluid accumulator (160) to accumulate a fluid volume, and at least one load device (124), a bypass regulator valve (118) in fluid communication with the pump outlet (115), the bypass path (119), and the load path (121), and a controller (130) to direct the fluid flow to the load path (121) in response to the load path pressure being less than a low load path threshold pressure via the bypass regulator valve (118) and to direct the fluid flow to the bypass path (119) in response to the load path pressure being greater than a high load path threshold pressure via the bypass regulator valve (118).
摘要:
The invention relates to a method for displaying the position of a hydraulically actuated fitting, with a piston (121) in an actuating cylinder (1.2) for actuating the fitting (1.1), the piston being connected via two hydraulic lines (2, 3) to a changeover valve (7), by means of which the hydraulic lines can be switched between pressure-carrying feeding and de-pressurized return. The flow of the hydraulic fluid flowing through one of the hydraulic lines is converted into a plurality of electrical pulses, each of which corresponds to a predetermined volume unit of the hydraulic fluid. The changeover valve (7) is connected to supply lines (P, T) on which additional changeover valves for actuating additional fittings (In) are connected, and the changeover valves (7) are connected via a branch line (T1) to the common return line (T) provided for all fittings. A preload pressure higher than the pressure in the common return line (T) is maintained at each changeover valve (7) in the branch line (T1) to the return line (T). In addition, a program which processes the pulses from the flow sensor performs a learning cycle.
摘要:
A latching solenoid assembly is provided which includes a solenoid actuator (10). A housing (50) is also provided which has an axial passage (52). An intermediate piston (66) is moved by the solenoid actuator (10). A reaction member (70) is also placed within the housing axial passage (52) spring biased by a transfer spring (72) from the intermediate piston (66). The housing has a latching port (54) allowing pressure to latch the intermediate piston in position to set the force which is transmitted to the reaction member.
摘要:
A hydraulic system for an access arrangement having a platform configured for movement between a deployed position and a stowed position, the hydraulic system including: at least one hydraulic power unit configured to urge hydraulic fluid through a hydraulic circuit; at least one hydraulic cylinder directly or indirectly connected to a portion of the platform and configured to urge the platform towards at least one of the stowed position and the deployed position, wherein the at least one hydraulic cylinder is in fluid communication with the hydraulic power unit; and a pressure regulating valve in a path between the at least one hydraulic power unit and the at least one hydraulic cylinder, wherein the pressure regulating valve is operable to prevent the at least one hydraulic cylinder from urging the platform to the stowed position if a load on the platform exceeds a specified threshold.
摘要:
Die Erfindung betrifft ein hydrostatisches Antriebssystem einer mobilen Arbeitsmaschine, insbesondere eines Flurförderzeugs, mit einer Pumpe (1) und mindestens einem von der Pumpe (1) versorgbaren Verbraucher einer Arbeitshydraulik (2), der mittels eines elektro-hydraulisch betätigbaren Steuerventils (11), insbesondere eines Wegeventils, betätigbar ist, wobei zur Betätigung des Steuerventils (11) mindestens ein elektrisch betätigbares Vorsteuerventil vorgesehen ist, das mit einer Steuerdruckversorgungsleitung (25) in Verbindung steht. Zur Lösung der Aufgabe, ein derartiges Antriebssystem zur Verfügung zu stellen, dass hinsichtlich des Energieverbrauchs und der Wärmebelastung des Druckmittels verbessert ist und einen geringen Bauaufwand aufweist, wird erfindungsgemäß vorgeschlagen, dass zur Erzeugung des in der Steuerdruckversorgungsleitung (25) anstehenden Steuerdrucks ein mit der Förderleitung (4) der Pumpe (1) in Verbindung stehendes Druckminderventil (26) vorgesehen ist.