Abstract: A pneumatic actuator for deploying flexible bodies and the like is disclosed. The actuator is a plurality of telescoping tubes made of high temperature resistant graphite material which are extended by the pressure of gases produced internally by a gas generator contained within the innermost tube. The extended tubes are locked in position automatically and venting of the gases from the tube interior is provided for simultaneously with full and locked extension of the tubes.

Abstract: A hydraulic system for trimming and tilting an outboard propulsion unit (10) includes both trim piston-cylinder units (22, 23) and a trim-tilt piston-cylinder unit (17). The flow of hydraulic fluid from the reversible pump (49) is controlled by a spool valve (26). A pressure relief valve (71) is mounted in the spool (50) to maintain pressure on one side of the spool (50) when the pump (49) is turned off to rapidly close the return valve (56) and prevent further movement of the piston-cylinder units.

Abstract: The present invention relates to a hoisting gear for patient-lifting device whereby a plunger device (6) is displaceably mounted in a hydraulic cylinder (4), is supporting patient-carrier means (3) such as a seat or a patient-carrying plate and is raisable my means of a pump device (8) provided to move hydraulic oil between two hydraulic-cylinder chambers (9a, 9b) separated by the plunger device, and whereby a lowering device (39) is provided to permit lowering of the plunger device by producing a counter flow of hydraulic oil between the hydraulic-cylinder chambers.

Abstract: Fluid introduced into an actuator moves the piston, against the force of a return spring, to extend the actuator. After the actuator has extended a sufficient amount to perform its intended function, the piston contacts and moves a sleeve type closure for an outlet port. The additional extension of the actuator moves the sleeve to open the outlet port. This allows fluid from the source to flow through the actuator and out through the outlet port to an expansible chamber in a second actuator. In a preferred system, the second actuator is also a single acting linear motor and it includes a return spring. At the conclusion of the function of both actuators, a bypass valve in a return line is opened to allow fluid to flow out from the expansible chambers of both actuators back to a reservoir. The fluid from the second actuator flows back to the outlet port of the first actuator and from such port through a passageway which connects such port with the inlet-outlet port of the first actuator.

Abstract: A starting arrangement for a reciprocating piston pneumatic hammer provides a passageway in the piston which couples a pneumatic piston subchamber to an exit port to exhaust pressurized pneumatic fluid from the subchamber to prevent the piston from centering.

Abstract: The present invention discloses a hydraulic clutch comprising friction plates; a hydraulic piston for pressing the friction plates; a pair of annular protrusions respectively formed at radially outer portion and relatively inner portion of the piston with an annular space therebetween, said protrusions being designed to press the adjacent friction plate; an oil passage formed in the piston through which the annular space is connected to a pressure chamber at the back of the piston; a check valve arranged in the oil passage, said valve including a ball forced to close toward the friction plates and partially projecting beyond the protrusions toward the friction plates; an accumulation chamber formed in the piston and connected to the annular space; and a drain means connected to a space in which the friction plates are arranged.

Abstract: Fluid introduced into an actuator moves the piston, against the force of a return spring, to extend the actuator. After the actuator has extended a sufficient amount to perform its intended function, the piston contacts and moves a sleeve type closure for an outlet port. The additional extension of the actuator moves the sleeve to open the outlet port. This allows fluid from the source to flow through the actuator and out through the outlet port to an expansible chamber in a second actuator. In a preferred system, the second actuator is also a single acting linear motor and it includes a return spring. At the conclusion of the function of both actuators, a bypass valve in a return line is opened to allow fluid to flow out from the expansible chambers of both actuators back to a reservoir. The fluid from the second actuator flows back to the outlet port of the first actuator and from such port through a passageway which connects such port with the inlet-outlet port of the first actuator.

Abstract: A hydraulically operated actuator employs multiple metal-to-metal static seals to isolate the hydraulic fluid and to isolate the actuator from surrounding contaminating (ambient) fluids. A housing contains at least two linearly spaced apart chambers. A piston reciprocates from a retracted position to an extended position (power stroke) and from the extended position to the retracted position (return stroke) in one of the chambers (hydraulic chamber). The hydraulic chamber is separated by the piston into two sections, one of which contains high pressure hydraulic fluid and the other of which contains low pressure hydraulic fluid. A first static metal seal ring unit is designed to seal first at the completion of the power stroke of the piston to isolate the low pressure hydraulic fluid section from external contaminating fluids which may be at a higher pressure.

Abstract: A fluid actuator where an outside cylinder envelopes an inside cylinder producing four chambers, two for the power stroke and two for synchronization, for application where two or more cylinders are to drive a single load such that all cylinders advance at the same rate by cross plumbing synchronizing chambers. The combination is provided with valve means which opens at the end of each stroke to realign the actuators.

Abstract: A hydraulic trim-tilt system 15 for an outboard motor 10 includes a hydraulic trim-tilt piston-cylinder unit 16 pivotally connected to both the transom bracket 11 and the swivel bracket 12. Hydraulic trim piston-cylinder units 22 are mounted in the transom bracket 11. A pilot operated check valve 43 mounted in the piston 38 of one of the trim piston-cylinder units 22 serves to limit the maximum pressure in the system when the trim piston-cylinder units 22 have reached the end of their stroke.

Abstract: Dual function valve assemblies mounted within the operating piston of a power steering servomotor, control the flow of pressurized fluid between opposing piston chambers to both limit travel of the piston and limit the maximum pressure developed within the pressurized chamber by cutting off the pressure as the piston approaches a limit position and relieving excess pressure during piston travel.

Abstract: An improvement in a reciprocating engine used in an energy recovery system wherein the inlet valves to the cylinders of the engine are operated by independently time adjustable actuating means.The system for recovering energy from a pressured reactor comprising a reactor, a reciprocating engine connected to the reactor to receive reaction effluent from said reactor thereby driving the pistons of the reciprocating engine by expansion of the effluent and recovery apparatus downstream of the engine for recovering products from the effluent.The expanding reactor effluent is used to drive the pistons which are especially valved in conjunction with the effluent inlet port in the cylinder to facilitate handling the effluents to adjust the flow into an expansion chamber to obtain maximum recovery, the pistons in turn operate a crankshaft through a crosshead which may power compressors or operate a generator to produce electricity.

Abstract: The poppet trip device of the present invention is adapted for hydraulic cylinder units having a poppet axially movable within a poppet sleeve extended through the piston of the hydraulic cylinder unit. A head end of the poppet extends outwardly from the piston for engaging the head end of the cylinder in response to movement of the piston to the cylinder head end whereby the poppet is unseated and fluid communication is established through the poppet sleeve. Since the piston is spaced from the free end of the piston rod, however, engagement of the piston rod with the base end of the cylinder leaves the base end of the poppet spaced from the cylinder base end. The trip device or contact member of the present invention therefore is supported between the cylinder base end and piston for engaging the base end of the poppet in response to movement of the piston rod to the cylinder base end whereby the poppet is unseated and fluid communication is established through the poppet sleeve.

Abstract: A double-acting hydraulic jack has a cylinder, a piston dividing the cylinder into first and second chambers of variable volume on opposite sides of the piston, and a piston rod with first and second passages opening into the first and second chambers respectively. The piston is moved by supply of pressurized fluid to one passage or the other. An end-of-stroke device is provided to relieve the high pressure applied to the first chamber when the piston comes to the end of its stroke under the action of the pressure fluid supplied to that chamber through the first passage. The device comprises a bore in the piston. The axis of the bore is parallel to the piston axis. The bore contains a small moveable rod urged to project from the bore into the second chamber by high fluid pressure taken from the first passage to move a sliding sleeve in the bore. This sleeve movement is transmitted to urge the small rod and also blocks a third passage leading to the bore from the first passage.

Abstract: A trim-tilt device for marine propulsion devices wherein a cylinder and a piston rod slidably fitted in the cylinder are provided to be connected respectively with a propulsion device which in turn is connected to a hull so as to be rotatable in a vertical plane, and with the hull. A tilt piston is fitted to the tip of the piston rod and a free piston is arranged on the bottom side of the cylinder as opposed to the tilt piston and a trim piston is fitted to the tip of a pipe slidably fitted to the above mentioned piston rod. The trim piston is arranged on the opposite side of the tilt piston as opposed to the free piston and is slidably fitted in the above mentioned cylinder. Oil inlet and outlet ports are provided at both ends of the cylinder Stoppers and check valves are provided for controlling the oil pressure within the piston and cylinder arrangement. The trim-tilt device permits a trimming and tilting operation with a single cylinder.

Abstract: Centering and cooling equipment for a hydraulic vibration generator, with a pulsation generator pressurizing a cylinder containing a movable piston, composed of a feed system and a flushing system. The feed system includes spring-loaded non-return valves connecting a fluid reservoir to feed pipes connecting the pulsation generator to the cylinder chambers, and operates to supply cool pressure fluid from the reservoir when pressure in the cylinder chambers falls below a predetermined level. The flushing system includes a control bush/control plunger unit, bush and plunger of which are respectively connected to the piston and cylinder or vice versa, the plunger cooperating with channels in the bush to connect either feed pipe to a return passage according to the off-center position of the plunger in the bush. This system operates to withdraw a quantity of pressure fluid, dependent on pressure and stroke, from the cylinder chambers with each piston stroke.

Abstract: A hydraulically operated lifting device, such as a portable swinging-arm floor jack a low-rise forklift, or a high-rise forklift is provided with a piston-and-cylinder actuator having a closure member at one end of the cylinder through which a bore extends which supports a piston of the desired length and which is of uniform diameter throughout. The closure member has a radial bypass opening to a central point of the bore which communicates with a reservoir surrounding the cylinder and the inner end of the piston is provided with a passage which communicates with the bypass opening at the outer travel limit of the piston to recirculate fluid to the reservoir to prevent further pressure build-up. The bore includes fluid seals on each side of the bypass opening to prevent fluid leakage.

Abstract: The maximum operating pressure for the fluid servomotor of a fluid power operated steering system is varied as a function of steering displacement by varying the spring prestress bias on a relief valve controlling fluid discharge from the operating chamber of the fluid servomotor. The valve spring prestress is controlled by a spring engaged plunger that is displaced relative to the servomotor piston during steering displacement.

Abstract: A hydraulic circuit for supplying fluid to a ram to move an elongated member about a fixed axis on a frame includes a reservoir, pump, valve and conduits connected to opposite ends of the fluid ram. The fluid ram includes a cylinder pivoted on a ram pivot on the frame adjacent to and outside the fixed axis and the elongated axis of the member is moved across the ram pivot as the member is moved between working and transport positions. The hydraulic circuit incorporates a valve element carried by the piston and moved from a seated position at the critical time when the elongated axis is generally coincident with the ram axis to interconnect the two cylinder chambers and assist in moving the axis across the ram axis.

Abstract: A device for varying the angular setting of the blade of an earthmoving vehicle by means of a pair of double acting hydraulic cylinders in which only one of the cylinders receives pressure direct from a pump. The piston of that cylinder acts on one end of the blade and at the same time transmits pressure fluid through a hydraulic circuit to the piston of the other cylinder acting on the other end of the blade whereby the two pistons move in opposite directions. The hydraulic circuit includes a control valve for reversing the direction of movement of the pistons, the same cylinder being pressurized by the pump in both directions of movement of the pistons. Pressure fluid leakage loss compensating means are provided in each piston.

Abstract: A gripping arrangement includes a gripping member operatively connected with a differential both-side acted piston movable in a pneumatic or hydraulic cylinder. The piston stroke includes a first step and a second step. The pressure acted upon the piston to move the same into the respective gripping position is partially counteracted at the first step so as to eliminate an undesirably fast movement of the gripping member during at least initial portion of the stroke. The remaining portion of the stroke the piston moves under full pressure exerted by the pressure medium supplied in the cylinder without any counteracting effect.

Abstract: A hydraulically operated vibration exciter for a vibrating compactor of the kind comprising a piston in a cylinder, the piston and cylinder being arranged to move to and fro relative to each other, a source of liquid under pressure, a pressure line connecting the source to the cylinder and means for causing the liquid to move to and fro between the source and the cylinder to bring about the relative movement between the piston and cylinder is cooled by a method in which, during the relative movement, a quantity of the liquid is withdrawn from the cylinder and this quantity is not returned to the cylinder in the subsequent stroke, but is replaced by a fresh quantity of liquid at a lower temperature.

Abstract: A controllable hydraulic valve mechanism for reciprocating engines or pumps including a drive piston, operable by a cam is provided with control edges and projects into a drive cylinder; a working piston which operates the valve directly and is guided in a working cylinder. The valve mechanism provides a continuous communication between the drive cylinder interior and a second reservoir which absorbs a substantial part of the energy produced by the lift of a cam. Control sleeves surround the drive piston and are operable by actuating means operable from outside the drive cylinder. Each of the control sleeves has a control ring groove which cooperates with control edges provided in the drive piston. A further sleeve in the working cylinder surrounds the working piston, is rotatable by actuating means operable from outside the working cylinder, and is provided with a control ring groove for varying the valve lift.

Abstract: The use of the air-spring in automatically retracting (or extending) an air cylinder after it was extended (or retracted) by the air pressure supplied from the compressed air line is disclosed.

Abstract: An improved pneumatic operating mechanism construction is provided including the usual stationary operating cylinder with a movable reciprocally-operable driving piston member movable therewithin, and having an extremely-fast pneumatic valve-device cooperable with a movable valve-sealing member attached to, and carried by, the driving side of the movable driving piston. Additionally, a valve-piston bore is provided internally within the stationary valve-housing member, within which reciprocally pneumatically operates the movable valve piston.An exhaust-port opening is provided being pneumatically communicating to the region interposed between the movable valve piston and the movable valve-sealing member, which is carried by the movable driving piston. The result is an extremely-fast valve action providing for high-pressure operating fluid, such as compressed air, for example, to be provided to the driving face of the movable driving piston.

Abstract: This invention relates to a non-rotatable fluid powered nozzle and valve combination which includes a cylinder having a piston reciprocally received therein for movement between two reciprocated positions and which defines two separated fluid chambers therewith. A piston rod secured to the piston is slidably received through one end of the cylinder, the cylinder being provided with two ports communicating with said two chambers, respectively. The piston and piston rod conjointly having a longitudinally extending passage therethrough. A hexagonal pin is disposed in one of said chambers and is slidably received in sealing relation by a hexagonal portion of the aforesaid passage. The pin is secured in the other end of the cylinder for limited radial but against longitudinal movement with respect to the cylinder.

Abstract: A heating chamber seal is provided for a heating chamber combustion engine. A piston is provided with an extension on the flat bottom of the piston which towers upwardly and during the upstroke reaches into a pocket of the cylinder head. The extension has a slit at the bottom of the piston, an opening in the cylinder wall, opening a path to the heating chamber which is located near the cylinder head so that in the highest position of the piston the slit in the piston and the opening in the cylinder wall line up with each other, keeping the opening in the cylinder wall closed in all but the highest position of the piston.

Abstract: A hydraulic jack comprising a cylinder, a piston slidable relative to the cylinder, pump means to supply pressurized fluid to the base of the piston, a seal between the piston and the cylinder, means for limiting the stroke of the piston in the cylinder, said means comprising a ring carried by the piston and arranged to expand into a groove in the cylinder wall when the piston reaches the end of its permitted travel, and means for selectively de-activating said stroke limiting means, in order to allow removal of the piston from the cylinder to renew the seal.

Abstract: A bypass vavle arrangement extends fixedly from the end wall of a double acting cylinder through the radial wall of a booster piston with a sliding sealed fit to block bypass flow between the pressure chambers at opposed faces of the piston between desired limits of piston travel. Bypassing of such flow from one chamber to another effects a pressure drop from the pressurized chamber to the chamber being exhausted to limit the pressure driving force on the piston and thus effect a desired limit or extent of piston travel and of the connected steering mechanism. The invention provides for such bypass flow by means of flow passages spaced on opposite sides of a central valve body portion which passages are of a length to span the radial wall through which the valve body has passed when the piston has reached a certain point of its travel in either direction.

Abstract: Dual double acting servomotors hydraulically pressurized are provided wherein the pistons have shunt valve means actuatable at limit of movement of the pistons to shunt high pressure fluid at one side of the piston to the low pressure side of the piston then being exhausted. This results in relieving the stress otherwise effected against steering mechanism limit stops by continued application of high pressure feed to the pressurized chamber. The system encompasses steering control and shunt circuit valve means automatically actuated by differential pressures so as to direct pressure and exhaust flow selectively to and from the chambers of the respective cylinders from an engine driven pump and a manual metering pump for operating the steered wheels of heavy duty vehicles and which valve means effects bypassing of the engine driven pump pressure feed directly to one servomotor while feeding the combined pressures of that pump and the metering pump to the other.

Abstract: The piston of a fluid ram is provided with an end of stroke braking means comprisng a pusher adapted to contact the end wall of the ram cylinder as the piston approaches the end wall to restrict the flow of fluid from the outlet chamber of the ram to an outlet part. As the ram moves nearer the end the pusher opens a valve in the piston to connect the inlet chamber of the ram to the outlet part.

Abstract: Mounted between a frame and a dozer blade at opposite sides of vertically spaced stabilizing and ball joint connections joining the frame and blade are a pair of hydraulic angling actuators which are operative to angle the blade about a vertical axis defined by the connections. A hydraulic tilt actuator is connected between the frame and blade in the vicinity of the stabilizing connection and is operative to tilt the blade about a fore-and-aft axis passing through the ball joint connection. Pressure relief circuitry including a normally closed relief valve is connected to the angling actuator and the relief valve is opened in response to a predetermined pressure build-up in the angling actuators, as occasioned by changes in the location of the points of connection of the angling actuators with the blade during tilting of the latter, to exhaust fluid from the angling actuators to permit extension or retraction thereof.

Abstract: A combination slave cylinder and relief valve for controlling release of a valve lever from a detented position. The valve is operated by pressurized fluid and is arranged to relieve the fluid pressure at a preselected value above that required for release of the lever.

Abstract: Disclosed herein is a marine propulsion device comprising a tilt hydraulic cylinder-piston assembly connected between a first member adapted to be attached to a boat and a second member connected to the first member for vertical swinging movement relative to the boat, and a trim hydraulic cylinder-piston assembly connected to the first and second members. Also provided is a hydraulic system connected to the tilt and trim hydraulic cylinder-piston assemblies for pressurization thereof.In one embodiment, the trim assembly includes a cylinder, a piston assembly located in the cylinder and having a first piston with a port therein and a second piston spaced axially from and fixedly connected to the first piston, together with a piston rod, means connecting the piston assembly to the piston rod for limited relative movement therebetween, valve means normally closing the port, and means for operating the valve means to open the port upon movement of the piston assembly to a predetermined position.

Abstract: The actuator comprises a cylinder of non-circular cross section, two types of pistons and a piston rod which is provided with at least one spiral male thread having a pre-determined helical angle at a pre-determined pitch. One of the piston is mounted on the piston rod for rotation relative thereto while being fixed against axial displacement therealong, and is provided with two relief pressure control valves opening in respective opposite directions, and the other piston is provided with at least one female spiral thread engaged with the male thread on the piston rod. The rod can thus reciprocate in the cylinder in opposite axial directions and can rotate, relative to the cylinder, in opposite angular directions.

Abstract: A multi-disc hydraulically operated friction clutch is provided with valve means in the form of longitudinally split plugs received in the drain openings of the plunger and varying the flow passage area of these openings, depending on the position of the plunger. Said plugs of the valve means are displaced, on the one hand, by the contact thereof with the pressure disc of the clutch, and, on the other hand, by their abutting against the housing of the clutch. By selecting the ratings of the valve means, i.e., the dimensions of the drain slit in the plugs, it is possible to ensure any required degree of smoothness of engagement of the clutch, the pressure disc acting upon the package of the friction discs with a gradually varying effort, proportional to the rate of draining of the working fluid through the plunger.