A dynamic load damping apparatus is employed in a hydraulic steering system control circuit of an aircraft. The dynamic load damping apparatus is positioned in the hydraulic steering system control circuit in parallel with a control valve of the control circuit that functions as the hydraulic fluid source of the control circuit and an actuator that controls movements of a nose gear of the aircraft. The dynamic load damping apparatus dampens loads transmitted to the hydraulic actuator that controls the steering movements of the nose gear on the aircraft.

Disclosed is a hydraulic pilot valve which is provided with an orifice so as to reduce vibration of a valve and minimize impact applied to a valve even when a valve is suddenly operated. At least some of hydraulic oil supplied to a supply chamber flows to a valve chamber or a central pipeline through a damping unit according to elevation of a spool.

A fluid pressure control device includes a switching valve configured to operate in conjunction with the control valve by the pilot pressure led through the pilot valve to switch work of the operation check valve. The switching valve includes a pilot chamber to which the pilot pressure is led, a spool that moves in accordance with the pilot pressure of the pilot chamber, a bias member that biases the spool in the valve closing direction, a collar detachably installed in the pilot chamber, and a piston slidably inserted into the collar, the piston being configured to receive the pilot pressure on a back surface thereof and give thrust force to the spool against bias force of the bias member.

Hydraulic valves for dampening pressure spikes and associated methods are disclosed herein. In one embodiment, a hydraulic valve for dampening pressure spikes includes: a spool configured to move axially inside the hydraulic valve; and a sleeve configured to at least partially house the spool. A location of the spool with respect to the sleeve may determine a flow of a working fluid through the hydraulic valve. A viscous damper is at least partially housed inside an opening in the spool, and a viscous friction between the viscous damper and the opening in the spool slows a motion of the spool.

A control device, for a hydraulic consumer (22) and susceptible to vibrations, includes a valve (24) having a control spool (40) controllable by an actuating device (46). The valve (24) has a pressure supply port (P), to which a pressure compensator valve can be connected, which can be supplied with pressure fluid from a pressure supply device. The actuating device (46) has a motor (74). A load-pressure-dependent force on the control spool (40) can be generated by a control device (66). That force at the control spool (40) acts on an electronic motor controller (208) of the DC motor (74), which detects a change of the force and acts as a damping of the vibrations of the consumer (22) against this change of force.

A dynamic load damping apparatus is employed in a hydraulic steering system control circuit of an aircraft. The dynamic load damping apparatus is positioned in the hydraulic steering system control circuit in parallel with a control valve of the control circuit that functions as the hydraulic fluid source of the control circuit and an actuator that controls movements of a nose gear of the aircraft. The dynamic load damping apparatus dampens loads transmitted to the hydraulic actuator that controls the steering movements of the nose gear on the aircraft.

A throttle check valve includes: a poppet valve body that has an orifice formed at one end and has a hole portion formed at a side portion; a plug that has a tubular shape to surround the poppet valve body, and functions as a valve seat to come into contact with the poppet valve body; and a spring that biases the poppet valve body and the plug functioning as the valve seat in directions to come into contact with each other. When the spool is at the second position, the plug forming the distal end portion of the spool and the plug arranged in the housing come into contact with each other. The plug is provided with a protruding portion that comes into contact with the poppet valve body.

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 the regeneration position, 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. A further valve 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.

Electro-hydraulic servo-valves and related methods are disclosed herein. An example electro-hydraulic servo-valve includes an inlet to receive a fluid from a reservoir, a torque motor, a chamber, the fluid to return to the reservoir via the chamber, and a flexure tube coupled to the torque motor. At least a portion of the flexure tube is disposed in the chamber. The flexure tube includes a nozzle to deliver the fluid to an actuator. The example electro-hydraulic servo-valve includes a damper operatively coupled to the flexure tube. The damper is disposed in the chamber.

A throttle check valve includes: a poppet valve body that has an orifice formed at one end and has a hole portion formed at a side portion; a plug that has a tubular shape to surround the poppet valve body, and functions as a valve seat to come into contact with the poppet valve body; and a spring that biases the poppet valve body and the plug functioning as the valve seat in directions to come into contact with each other. When the spool is at the second position, the plug forming the distal end portion of the spool and the plug arranged in the housing come into contact with each other. The plug is provided with a protruding portion that comes into contact with the poppet valve body.