Proposed are directional control hydraulic valves and a system including the same, the system including: a first valve controlling a flow of a fluid flowing thereinto from a first input port by being interlocked with a solenoid valve that is switched to an excited (on) state or non-excited (off) state; and a second valve connected to the first valve and controlling a flow of the fluid flowing thereinto from the first valve by a fluid flowing thereinto from a second input port or a third input port, wherein at least a part of the fluid having been passed through the first valve is discharged through a first output port and then flows into the second input port or the third input port. In addition, the system including at least two directional control valves may be provide, whereby multiplexing of the system may be implemented.

A valve includes a set screw that is screwable into and out of a complementary female threaded opening in a valve part for changing a setting of the valve, for changing an adjustable flow restriction of the valve, in which the set screw includes a free outer end that projects outside the valve part, and a gripping part on its free outer end for a tool to be engageable thereupon. The free outer end of the set screw includes a male thread onto which a locking nut is screwed. A protective cap is provided for covering the free outer end, that includes a first cap portion with a rotation space for fitting freely rotatable over the locking nut, and a second cap portion with a complementary female thread that is screwed onto the male thread towards a locked position.

A servo valve for precisely controlling a position of a pneumatic cylinder does not require a servo amplifier and a small sized and/or high durability servo valve unit. The servo valve comprises a unit body having first and second portions, first and second valve portions, first and second seal members that open and close the first and second valve portions, respectively, first and second drive mechanisms that drive first and second seal members by first and second electric pulses, respectively, a supply flow path between the first end and first valve, an exhaust flow path between the second end and second valve, a common flow path connected to the supply and exhaust flow paths via first and second valve portions, and a drive flow path connected to the pneumatic actuator. First and second drive mechanisms are arranged in a drive mechanism arrangement portion located between first and second end portions.

A fluid control device includes a housing partitioned into an input chamber and an output chamber by a housing land portion extending on the radially inner side, a spool arranged inside the housing and provided with a spool land portion that is configured to reciprocatively slide with respect to the housing land portion and that extends on a radially outer side of the spool, and a biasing member configured to bias the spool toward a valve closing position, wherein upon receiving drive force from an exterior, the spool is moved against bias force of the biasing member, and the input chamber and the output chamber communicate with each other, the spool includes a large diameter portion arranged in the input chamber and having a larger diameter than the spool land portion, and the large diameter portion and the housing land portion form a poppet valve structure.

A load sense pressure regulating system is provided. The load sense pressure regulating system can be operable between a flow regulation mode and a pressure limiting mode. When the load sense pressure control system is in the flow regulation mode, flow between a load sense inlet and a pilot vent are metered by a main poppet. The load sense pressure regulating system can also include a control valve downstream from the pilot vent that is configured to control a relief setting of a relief valve to regulate the load sense pressure within a desired operating range.

An actuator includes a housing defining an inlet port, a piston and a return spring disposed within the housing, and an elastically deformable element. The return spring is configured to apply a biasing force to the piston to move the piston to a spring return position. A first fluid pressure applied to the inlet port moves the piston against the biasing force of the return spring to a first actuated position in which the piston indirectly engages a stop portion of the actuator housing. A second fluid pressure, greater than the first fluid pressure, applied to the inlet port moves the piston against the elastically deformable element to compress the elastically deformable element to move the piston to a second actuated position beyond the first actuated position.

An example valve includes: a plurality of ports comprising: a first port, a second port, and a third port; a spool configured to block fluid flow from the first port to the third port while allowing fluid flow from the third port to the second port when the valve is in an unactuated state; a spring applying a biasing force on the spool in a proximal direction, wherein when the valve is actuated, the spool moves in a distal direction against the spring, thereby allowing fluid flow from the first port to the third port while blocking fluid flow from the third port to the second port; and a turbine configured to rotate as fluid flows from the first port to the third port when the valve is in an actuated state.

An apparatus includes a hydraulic circuit that is configured to selectively open fluid communication between one portion of the hydraulic circuit and another portion of the hydraulic circuit, such as a reservoir, based on the flow of the hydraulic fluid in the one portion. When the flow of hydraulic fluid exceeds a selected threshold in the one portion of the hydraulic circuit, the flow of fluid urges the opening of a hydraulic component of the hydraulic circuit to allow fluid communication between the one portion and the reservoir to discharge fluid from the one portion.

A positioner drive for controlling a valve positioner with pneumatic output is configured to be mechanically coupled to a valve of the valve positioner with pneumatic output for controlling the valve positioner with pneumatic output.

A magnetic force compensator for at least partially compensating a closing force required to shift a valve of a pneumatic positioner into a closed position using a magnetic device, the magnetic device including a permanent magnet; and a magnetic counterpart; wherein the magnetic device and the magnetic counterpart are configured to interact to create an attracting force for the at least partially compensation of the closing force; and wherein the magnetic force compensator is configured to be mechanically coupled to the valve of the pneumatic positioner.