An aircraft store ejector systems and subsystems thereof. Embodiments can include a two-reservoir re-pressurization system wherein a remote reservoir is used to maintain desired pressure in a local ejector reservoir. The system can include a release valve having a vent valve and valve piston. The release valve can control release of pressurized gas to a pitch control valve. The pitch control valve can be configured to distribute the pressurized gas between two or more ejector piston assemblies. One or more of the ejector piston assemblies can include multiple concentric piston stages and piston chambers, the piston chambers configured to contain a volume of gas. The ejector piston assemblies can be configured to compress the volume of gas within the piston chambers as the piston stages are extended out from the aircraft. Such compression can provide a return force to the piston stages.

A hydraulic pressure amplifier arrangement (1) comprising a supply port (IN), a return port (R), a high pressure port (H1), and a pressure amplifier unit (2) having a low pressure inlet (3) connected to the supply port (IN) and a high pressure outlet (4) connected to the high pressure port (H1) is described, wherein the pressure amplifier unit (2) comprises an amplification factor. In such a hydraulic pressure amplifier arrangement it should be possible to allow simply releasing off pressure at the high pressure port while keeping small unnecessary energy consumption. To this end a control valve (8) is arranged in a connection between the high pressure port (H1) and the return port (R).

The invention relates to a valve, which is characterized in that between a neutral position (38) of a control spool (STS) and one of its end positions (34, 42) a regeneration position (36) is provided, in which two utility ports (A, B) are interconnected in a fluid-conveying manner, or a floating position (40) is provided, in which these utility ports (A, B) are interconnected in a fluid-conveying manner. The invention relates to a further valve, which is characterized in that by a further motion of the control spool (STS) in the same direction, as that, in which a fluid connection is established between the utility ports (A, B) starting from the neutral position (38), this fluid connection is interrupted.

An accelerator-equipped pneumatic cylinder includes a cylinder block, a switch valve, and pneumatic cylinder. The cylinder block defines therein a piston chamber and a pressure chamber. The switch valve has a valve seat installed in the cylinder block and between the piston chamber and the pressure chamber. A controller is installed in the valve seat for controlling the piston chamber and the pressure chamber to be communicated with each other or not. The pneumatic cylinder has a piston portion received in the piston chamber, and has a shaft portion extending outward from the cylinder block. At a moment when a channel is made opened by the controller and the piston chamber and the pressure chamber come into communication with each other, the piston portion is pushed by a pressure medium at an accelerated speed, so that the shaft portion is pushed outside the piston chamber at the accelerated speed.

A hydraulic system for recovering potential energy of a load implement of a mobile construction vehicle. The hydraulic system includes first and second actuators and control valving. The first and second actuators are configured to be coupled to the load implement for controlling raising and lowering of the load element. The control valving is operable between a first position at which, during a lowering of the load implement, the control valving directs hydraulic fluid from one of the first and second actuators to an accumulator to charge the accumulator, and a second position at which the control valving directs hydraulic fluid from the accumulator to one or more of the first and second actuators to power the one or more of the first and second actuators to raise the load element.

A valve for controlling a flow of a fluid between a source, reservoir, a vent, and pressure-based device. The valve has multiple positions each having a source port fluidly coupleable to the source, reservoir port fluidly coupleable to the reservoir, device port fluidly coupleable to the pressure-based device, and venting port configured to vent the fluid. The multiple positions are separately selectable and include a fill position having a fill conduit fluidly coupling the source port and device port, a recycle position having a recycle conduit fluidly coupling the reservoir port and device port, and a vent position having a vent conduit fluidly coupling the vent port and device port. The fill conduit, recycle conduit, and vent conduit each communicate the fluid only when a corresponding one of the multiple positions is selected, and the multiple positions are configured to prevent selection of more than one at a time.

Provided is a swing-back preventing apparatus capable of preventing a hydraulic actuator in a stop state from operating by undesired load. The swing-back preventing apparatus includes a housing, a piston, and a pair of biasing members. First and second spaces are formed between the piston and the housing, and the piston includes a pair of communication passages that are communicable with first and second spaces. When the piston is located at a first offset position, the first space is blocked from a first port. When the piston separates from the first offset position, the first space is connected to the first port. When the piston is located at a second offset position, the second space is blocked from a second port. When the piston separates from the second offset position, the second space is connected to the second port. When the piston is located at a position on the first offset position side of a neutral position, a first communication passage is connected to the first space. When the piston is located in a range from the neutral position to the second offset position, the first communication passage is blocked from the first space. When the piston is located at a position on the second offset position side of the neutral position, a second communication passage is connected to the second space. When the piston is located in a range from the neutral position to the first offset position, the second communication passage is blocked from the second space.

An automatically actuated shunt valve system opens and closes a passage between two chambers of a powered element operated by a power source. The shunt valve system includes a coupler connecting the powered element with the power source through two mating coupling elements. One of the coupling elements includes a valve contact and the other includes a shunt valve assembly. The shunt valve assembly includes a valve chamber connected with both chambers of the powered element, a valve element opening or closing a flow path between the conduits, and a shaft for moving the valve element. The shaft engages the valve contact to move the valve element to close the flow path when the coupling elements are mated together, and moves the valve element to open the flow path when the shaft disengages from the valve contact as the coupling elements are disconnected from one another.

A fluid valve has a valve plug configured as follows. In order to control a flow rate of a fluid between a first pressure chamber and a second pressure chamber, the valve plug is provided so as to be openable and closable in accordance with a difference between forces generated by pressures in the pressure chambers and resilience of an elastic member. The fluid valve includes an opening motion promoting portion. The opening motion promoting portion promotes an increase in degree of opening of the valve plug after the valve plug has been opened.

Flow control over a hydraulic pump and flow dividing control of a plurality of directional control valves associated with actuators can stably be exercised even in a case in which differential pressures across the directional control valves are quite low, an abrupt change in a flow rate of the hydraulic fluid supplied to each actuator is prevented and excellent combined operability is realized even in an abrupt change in a demanded flow rate at a time of transition from a combined operation to a sole operation, and realizing excellent combined operability, and a meter-in loss in each directional control valve is reduced to realize high energy efficiency. Demanded flow rates of the directional control valves are calculated from input amounts of operation levers, openings of flow control valves are controlled using the demanded flow rates, a meter-in pressure loss of a predetermined directional control valve is calculated from the demanded flow rates and meter-in opening areas of the directional control valves, and a set pressure of an unloading valve is controlled using a value of the meter-in pressure loss.