Abstract: An electro-magnetically operated bidirectional two-way air valve capable of changing state at high pressure differentials or high flow rates in either direction has a body which defines a main bore in which an armature is slidably received. The body has a first port and a second port with a seat between them formed at the end of the main bore and a plastic valve element is secured to a neck portion of the armature to seat against the seat when the valve is closed. Frusto-conical surfaces are formed on the valve element and on the neck portion and a transversely extending pin across the main bore retains the armature in the main bore. In a second embodiment, an end of the armature tapers so as to reduce drag, a powder metal flow restrictor is provided in an axial bore in the armature to reduce shift speed and an elastomer bumper is provided to reduce operating noise.

Abstract: A double latching hydraulic valve of the type that either stays open or stays closed at high pressures and only changes state (between open or closed) at low pressures has three ports, with a main valve between the first and second ports which is opened or closed by a poppet. The first port is always in communication with a pressure chamber which biases the poppet against the main valve seat, and the pressure chamber is placed in communication with the third port, which can be connected to tank pressure, only in the open position of the poppet. Thus, a high pressure is provided in the pressure chamber to keep the poppet closed at high pressures, and a low pressure is provided in the pressure chamber to keep the poppet open at high pressures, without excessive leakage through the valve when it is closed.

Abstract: A proportional pressure control valve has a poppet including a control pin for seating against the seat and which is pressed into a generally tubular armature. One end of the armature proximal to the seat has an enlarged diameter and fits into a cup shaped recess of the housing in an extreme position of the poppet. A smaller diameter of the armature is journaled in a magnetic sleeve bearing at a distal end of the poppet and the control pin is journaled in a sleeve bearing at the proximal end of the popper. A plastic plug covers the distal end of the armature and an annular gap is created at the distal end of the armature bearing between the armature and the housing.

Abstract: The magnetic interface between the housing and armature of a poppet type electromagnetically actuated fluid control valve creates a magnetic flux path through opposing axially and radially facing surfaces of the housing and armature to reduce the pull-in voltage of the valve at large axial gaps between the armature and housing.

Abstract: A radial piston pump of the type, in which an excentric rotor (7) is adapted to cause the pistons (4) to perform a reciprocating movement within radial cylinders (3) in the pump body (1), the radial inner ends of the pistons (4) being each provided with a broadened foot (6), said broadened feet (65) being kept in contact with the rotor (7) also during the suction strokes of the respective pistons (4) by means of a coupling ring (26) of a substantially L-shaped cross section, the axial ring portion (26a) of which engages the radial outer end faces of the broadened feet (6) and the radial portion (26b) of which keeps said ring (26) axially in place.

Abstract: A pump having a reciprocating piston/plunger unit adapted to be actuated by a railway wheel rolling over it has a unitary plunger and piston, with the piston double-acting so that when the outlet pressure exceeds a certain value, the plunger remains retracted. An accumulator is provided in fluid communication with the outlet so as to store accumulated hydraulic pressure.

Abstract: A liquid tank cap incorporates a two-way relief valve in which an annular valve disc has one side sealed against a seal adjacent to its inner diameter and the other side sealed against a seal adjacent to its outside diameter. When subjected to a pressure differential in either direction, the disc deflects so as to increase its concavity and allow air passage by one or the other seal, depending upon whether the pressure in the tank is subatmospheric or superatmospheric.

Abstract: A caster has a stationary hub with a bearing between the hub and a floor engaging wheel ring which allows the wheel ring to rotate relative to the hub. Torsional elastomeric elements mount the hub between spaced support arms radially inward of the bearing and are positioned eccentrically relative to the axis of rotation of the wheel ring so as to suspend the hub resiliently between the arms. In an alternate embodiment, the hub is cantilevered from a single support arm.

Abstract: A self-contained rotary actuator assembly has a pump assembly, a precharged hydraulic circuit, and a rotary vane actuator in a single unit. The pump assembly is a bi-directional electric motor driven gerotor pump which is manifolded to a module assembly in which the control elements of the hydraulic circuit are housed. Upon the application of the pressure for driving the rotary actuator in either direction, a pilot operated hydraulic valve is shifted so as to communicate the rotary actuator with the pump. After the pump is turned off, an orifice for the pilot chamber of the valve bleeds the pilot chamber slowly so as to provide a delay in which the rotary actuator holds the convertible top extended or retracted to give the vehicle operator time to latch the top in its closed or open position. In addition, a gas charged precharge chamber in the hydraulic circuit maintains a precharge through a broad range of temperatures.

Abstract: A hydraulic fluid reservoir contains an extensible bladder which has its exterior exposed to the fluid and its interior vented to the exterior of the reservoir. The interior of the bladder is sealed from the hydraulic fluid in the reservoir. Depletion of the fluid from the reservoir results in distension of the bladder and replenishing the fluid to the reservoir collapses the bladder. The bladder is pleated and a tie-rod which holds the reservoir together extends through the bladder.

Abstract: A two stage pump has coaxial first and second stage reciprocating pumps with the second stage piston reciprocably driven by the first stage piston. Multiple sets of first and second stage pumps are provided, and the second stage pistons can be returned by supercharge pressure, a loose connection between the first and second stage pistons, or a spring. An accumulator which is charged on a compression stroke and discharged on an intake stroke may also be provided in communication with a pumping chamber to improve the efficiency of a pump.

Abstract: A hydraulic circuit comprising at least two double acting hydraulic piston-cylinder devices, for opening and closing a folding roof of a vehicle, with both ends of each piston-cylinder device each connected to a conduit supplied with pressurized fluid by a common hydraulic pump and to a return conduit leading to a source of hydraulic fluid, via 3/2 electrically activated valves. The 3/2 valves include a main ball (22) and seat (22a), with a check valve (32) of the ball seat type upstream of the main ball seat in a connection to the conduit supplied with pressurized fluid.

Abstract: Hydraulic cylinders made of fiber-resin composite materials have a central piston chamber section and bell-shaped internally threaded end sections. Cylinders are made by winding resin coated fibers over a mandril over which externally threaded sleeves are slipped and spaced apart so as to define the end sections. After curing the resin, the winding is cut in the areas of the sleeves to separate the cylinders. An expendable strip is wound onto the sleeves and in the cutting operation is cut into. A bearing, a seal cavity and an enlarged inside diameter at a piston rod end of the cylinder may also be provided using a method of the invention, with the cylinders being cut apart between the ends of sleeves and between the other ends of the cylinders.

Abstract: A hydraulic pressure reducing and relieving valve has a body with input, control and relief ports, a tubular spool slidably received within the body for selectively providing communication between the ports, and a tubular quill within the spool which the spool can slide over. The quill has a lumen which provides communication from one end of the spool to the other, so as to pressure balance the spool with relief pressure, and together with the spool defines a feedback chamber in communication with the control port which generates a force on the spool which opposes the operating force exerted on the spool by a solenoid. The spool may also be biased by a spring in the feedback chamber.

Abstract: A two stage pressure control valve has a poppet movable toward and away from a valve seat to vary the cross-sectional area of a passageway from an inlet to an outlet. The position of the poppet is dependent in part on the difference in pressure between a fluid pressure at the inlet which exerts an force on the poppet in one axial direction and a control pressure which is produced by a fluid flow from the inlet in a chamber downstream from the inlet and which exerts a force on the poppet in the opposite axial direction. The control pressure is controlled by an electromagnetic coil which can be variably energized to move an armature so as to vary a variable restriction downstream from the control pressure so as to vary the control pressure. A tube extends through and forms an axial sliding seal with the poppet and communicates a flow of fluid from the inlet to the variable restriction and the chamber is positioned adjacent to an exterior surface of the tube.

Abstract: A retainer for the drive shaft of a hydraulic torque wrench has an eccentric pivotably connected to the free end of the shaft which can be pivoted between an unlocked position and one or more locked positions and locked in any of the positions with a plunger. In the unlocked position, the eccentric does not overlap a bearing of the wrench so that the shaft and eccentric can be withdrawn axially from the wrench drive head. In the locked position(s), the eccentric overlaps and abuts an axial face of the bearing so that the eccentric cannot be drawn into the bearing, thereby securing the shaft against axial movement out of the wrench drive head in the direction from the eccentric toward the bearing.

Abstract: A hydraulic circuit for controlling the speed of multiple hydraulic fluid power devices when the flow demand of the devices exceeds the flow capacity of a pressure source supplying hydraulic fluid under pressure to the devices has multiple pressure controlled proportional flow supply valves for controlling the supply of hydraulic fluid to the power devices. Load sense pressures which indicate the pressure delivered by the valves to the corresponding devices are compared to determine the highest load sense pressure, which is compared to the supply pressure by a proportional speed sensing valve to regulate the pilot pressure. In the preferred embodiment, the pilot pressure is regulated by the proportional speed sensing valve to be equal to the differential between the supply pressure and the highest load sense pressure, and a limit control is provided in one form of the proportional speed sensing valve.

Abstract: A vibration isolator has four fluid filled variable volume load bearing chambers, with two arranged on one side of a core and the other two on the other side. The core and chambers are contained within a frame, with the chambers extending between the core and the frame, so that vibrating the core axially compresses or extends the chambers. Diagonally opposite pairs of chambers are each connected with a separate fluid track, and the two fluid tracks may be tuned to have different resonant frequencies or the same resonant frequency. The chambers are defined by elastomeric bodies which may be reinforced using a tubular shaped reinforcing element adjacent to the chamber, to help contain the pressures within the chamber without materially increasing the compression strength of the elastomeric bodies.

Abstract: A caster has two spaced apart wheels with an elastomeric torsional shock and vibration isolating suspension between them. The wheel axis is spaced longitudinally from a bearing axis to subject elastomeric disks positioned between the wheels to torsional shear stresses to help absorb shocks and vibrations. A snubber is provided for limiting the angular motion of the wheels about a bearing axis.

Abstract: A waste container crusher particularly adapted for crushing automotive type oil filters or other structurally rigid disposables containing hazardous waste has a housing with an open bottom which is closed off by an anvil plate. The anvil plate slideably receives three equiangularly spaced posts which are secured to a roof plate at the top of the housing, above the anvil plate. Nuts on the posts support the anvil plate below the roof plate, so that the anvil plate is suspended from the roof plate by the posts. The roof plate is secured to a hydraulic cylinder which produces a 10 ton driving force for a platen guided by the posts to crush a container placed on the anvil plate below the platen. In the anvil plate, four blind bores in a rectangular pattern in the top surface intersect a central blind bore extending from the bottom surface, and a smaller central through-bore provides communication between the lower central blind bore and the top of the anvil plate.