摘要:
A manual override for a hydraulic control valve spool includes a rotatable shaft having a threaded hole; a lever pin having a first end connected for movement with a hydraulic control valve spool and a second end having an external thread that is threadably received in the threaded hole; and the threaded hole and external thread include a mechanical antirotation element.
摘要:
A hydraulic actuator includes a hollow tube that has a first opening at a first end of the hollow tube and that has a second opening at a second end of the hollow tube. The hollow tube contains hydraulic fluid. A moveable magnet moves within hollow tube as a result of a magnetic field within the hollow tube. A magnetic field source located outside the hollow tube creates the magnetic field within the hollow tube. When the moveable magnet moves to the first end of the hollow tube, a first piston pushes hydraulic fluid out of the first opening. When the moveable magnet moves to the second end of the hollow tube a second piston pushes hydraulic fluid out of the second opening.
摘要:
A hydraulic control circuit, comprising a control line connected to a device to be controlled by fluid pressure in the control line; a time-out valve on the control line, the time-out valve having a time-out period during which time-out period operation of the time-out valve is delayed after actuation of the time-out valve; a pump connected to the control line for pressurizing the control line with fluid; and an arming valve operated by pressure on an arming line connected to the control line and the arming valve being connected to the time-out valve to reduce the time-out period in response to pressure on the control line.
摘要:
An exciting coil is wound on a cylindrical yoke provided with a pair of pole teeth, a cylindrical permanent magnet where N pole and S pole are magnetized in a radial direction is disposed so as to be movable in a hollow portion of the yoke and the permanent magnet is coupled toa spool byamagnet holder, and a displacement sensor is disposed in a hollow portion of the permanent magnet so as to be positioned on a center axial line of the permanent magnet, so that the displacement of the permanent magnet is detected by the displacement sensor and the degree of opening of the spool is controlled by performing feedback of the displacement to a control portion.
摘要:
A hydraulic control apparatus for a hospital bed includes a manifold having a manifold block with an inlet, an outlet, and a conduit in fluid communication with the inlet and the outlet, and a valve assembly having a valve with a portion moveable within the conduit between a first position blocking fluid communication between the inlet and the outlet and a second position in which the inlet is in fluid communication with the outlet. The control apparatus further includes a solenoid operable to move the valve from the first position to the second position in response to an electrical input applied to the solenoid, and a lever operable to move the valve from the first position to the second position in response to a manual input applied to the lever.
摘要:
A hydraulic control circuit for a hydraulic actuator, including a high-low pilot valve having a sensing port for connection to a flow line. A single pressure line connects the high-low pilot to a hydraulic actuator. A second line connects the high-low pilot to a reservoir. A normally closed relief valve is connected to the single pressure line for relief of excessive pressure. A normally closed override valve is connected to the single pressure line for manual override of circuit controls. A pump is connected to the single pressure line for pressuring the single pressure line. The hydraulic control circuit has a normally open time out valve on the single pressure line, the time out valve being set to close a pre-set time interval after being manually activated, to isolate the high-low pilot, from the single pressure line to the hydraulic actuator, until the time out period has elapsed. The override valve is connected to the single pressure line between the time out valve and the hydraulic actuator. The relief valve is connected to the single pressure line between the time out valve and the hydraulic actuator. The override valve, relief valve, high-low pilot, and the pump are connected between the first line and the reservoir.
摘要:
An arrangement for hydraulically operating a rear cover, covering top or the like (1) on a vehicle, with at least one double-acting hydraulic working cylinder (3), which, on the one hand, is connected to the vehicle and, on the other hand, to the covering top wherein its working chambers (8, 9) are in connection with each one side of a switched pressure source (12) via one check valve (10, 11) each, wherein both of the check valves have an mutually releasing device and each of the working chambers parallel with respect to the check valves is kept via a pre-stress valve (15, 16), which steers into the tank, at a specified pressure level. To make possible, in a simple and safe way, an emergency operation of the covering top (1) also in the common working cylinders having different volumes of the working chambers (8, 9) on the side of the piston and valve stem, between at least one working chamber (8, 9) and the corresponding releasable check valve (10, 11), a separate after-suction line (23) enters which leads to the tank (17) and in which a check valve (24) is inserted which is open in the direction of the working chamber (8).
摘要:
A valve assembly for a pneumatic machine including a valve body having a first end, a second end, a central bore extending through the ends and a plurality of flow ports formed in the body; a valve spool movable through the bore along an axis in response to the flow of gas through the valve, to selectively open and seal the ports; an main inlet valve for moving the valve spool a distance along the axis; and a manually actuated means for overriding the main inlet valve.
摘要:
In accordance with the invention, the hydraulic dual solenoid directional control valve embodying the invention includes means at each end of the hydraulic dual solenoid directional control valve which includes a hinge fixed to the coil at each end, a lever pivoted to the hinge and an elbow connected to the hinge and connected to a common rod. The rod has a non-circular sleeve, preferably square, which projects normally through a complementary opening in a projection on one of the hinges. When the rod is moved in one direction, the sleeve and rod are moved such that an interference fit is provided with rotation between the sleeve and the projection on one hinge causing the lever to yieldingly apply force to the pin of the corresponding solenoid, actuating the valve in one direction. When the rod is actuated in the opposite direction and then rotated after clearing the sleeve from the opening in the hinge, the sleeve provides an interference fit with the other side of the other hinge such that the lever on the other end of the valve is actuated and held in position having shifted the spool of the valve in the opposite direction.