Abstract: Small-sized engine operated by an expanding gaseous fluid, which comprises a cylinder (18), a piston (20) and an inlet valve (38), the upper parts of the cylinder (18) and the piston (20) cooperating momentarily with a perforated (29) resilient membrane (28) circumferentially secured to the cylinder (18) and performing the functions of a pneumatic seal temporarily.

Abstract: This invention relates to a fail-safe or auto-return actuator cylinder employing the air spring effect provided by compressed air trapped in an air-spring compartment; which air spring effect replaces the conventional mechanical coil spring employed in conventional fail safe or auto-return air cylinders. The air spring chamber integrally built into the cylinder body is connected to the compressed air supply tube through a check valve that provides the self-charging and self-recharging feature for the air-spring chamber and, consequently, the air-spring chamber remains fully charged with compressed air even when there is a compressed air leak from the air-spring chamber. The air-spring compartment stays charged or becomes automatically recharged even when there is a leak from the air-spring compartment as long as there is compressed air to actuate the cylinder.

Abstract: The thread winding machine includes a piston and cylinder unit, comprising a cylinder housing with first and second chambers and a dividing structure between said first and second chambers. A piston is movable longitudinally in the first chamber and a piston extension projects from said piston towards the second chamber. A port in the dividing structure receives the piston extension when the piston is near the dividing structure, thereby separating said first and second chambers. A thread guide is connected to the piston of the piston and cylinder unit for movement in combination therewith.

Abstract: A thermally powered engine which obtains energy from a closed heat transfer loop. The engine has two power cylinders. A piston is reciprocally mounted within each cylinder and divides the interior space of each cylinder into two portions. A piston rod is affixed to each piston and extends through the upper closed end of each cylinder. A flexible diaphragm is mounted in the lower portion of each cylinder and with the lower closed end of the cylinder forms a power chamber. A fluid fills the upper portion of both cylinders. A passageway between the cylinders permits the fluid to act as a free piston causing the piston of the cylinder in its exhaust stroke to force refrigerant from its power chamber to the condenser of the heat transfer loop. Refrigerant from the evaporator of the transfer loop flowing into a power chamber forces the piston upward during the pistons power stroke. Valves regulate the flow of refrigerant into and out of the power chambers of each of the power cylinders.

Abstract: A device of this nature incorporates at least one control piston displaceable within a casing, the casing having at least one venting nozzle authorizing the insertion of the piston into one of its possible operating positions, which nozzle may be shut off by means of an electromagnetically operated closing device for preparation of the outward displacement of the piston out of this operating position. To accomplish that such devices may manage with a substantially reduced electrical battery power for their electromagnetic closing device, a permanent magnet is provided which co-operates with a ferromagnetic member of the closing device, in such manner that the closing device continues to be held in its closing position while the control piston is being reversed, although the supply of electrical power to the closing device had already been turned off.

Abstract: A combined brake cylinder/air reservoir device in which a relatively small, tubular-shaped piston in a positioning chamber is connected to a larger power piston having an application chamber on one side and a release chamber on the other side in which air is stored in place of separate reservoirs. A replaceable cylinder liner is provided to receive different-sized power pistons. During a brake application, the power piston enters the cylinder liner and is displaced from the liner during brake release to provide free air flow between the application and release chambers and thereby facilitate piston return movement by means of a return spring. A dynamic pressure seal between the application chamber and positioning chamber engages the outer periphery of the tubular-shaped small piston, while a smaller diameter dynamic pressure seal between the release chamber and atmosphere engages the inner periphery of the tubular-shaped small piston.

Abstract: A self-contained, pilot-operated valve is provided with a plug for controlling the flow of a fluid through an orifice between inlet and outlet openings. A spring located about a stem projecting from the plug urges the plug into sealing engagement with the orifice. By means of a bellows surrounding the spring and having one end connected to the stem, an interior space is created, which space is in communication with the inlet opening through a restricted conduit. The interior space is also in communication with the outlet opening via a pilot valve. Operation of the pilot valve controls the pressure in the interior bellows space and hence the degree to which the bellows is compressed. This compression affects the plug stem and hence the position of the plug with respect to the valve seat.

Abstract: The invention provides a conduit blow out preventer utilizing movement of an annular piston to selectively effect the reduction of flow through the blowout preventer to a pre-determinable value or alternately, terminate flow therethrough altogether in response to the occurence of a pressure fluctuation in the fluid conduit to which the conduit is attached. An annular fluid conduit is defined between the interior bore of the annular piston and a support post. A discontinuous annular sealing element is provided in such fluid passage to provide an orifice, creating a pressure differential across the piston in the event of a biased flow surge. Axial movement of the annular piston results in closing of the outward fluid flow in the annular fluid passage and flow is then restricted to that permitted by a radially disposed orifice communicating with the annular fluid passage. A check valve in a fluid inlet is normally held off its seat by a connecting rod extending to the support post.

Abstract: An air cylinder has a main piston which is movable backwardly and forwardly under the control of air pressure and it is closed on at least one end with an axially extending damping bore which terminates in a closed end having a stop member adjacent this end. A vent hole connects to the interior of the cylinder to the damping bore and another vent hole connects into the cylinder main space. Each vent hole is advantageously connected to a throttle and check valve which permits inflow of air to the associated spaces and a throttled exit of the air depending on the position of the piston in the cylinder. The piston carries a damping piston in the form of a cylindrical extension thereof which is movable with the piston toward the closed end and has an open end with an axially extending damping bore therein having a check valve which closes the opening.

Abstract: An improved control line blow out preventer valve is provided, having a fluid pressure chamber interposed in a control line extending from a surface control panel to a downhole safety valve in a subterranean well. Axially spaced inlet and outlet openings are provided in the pressure chamber and a piston is reciprocally mounted intermediate the inlet and outlet openings. A sealing plug carried by the piston cooperates with a seal surrounding the inlet opening. A bypass passage through the piston mounts a check valve which permits free fluid flow in the direction from the control panel to the subsurface safety valve but only a restricted fluid flow in the opposite direction. A check valve is mounted in the outlet passage to prevent fluid flow from the subsurface safety valve to the control panel. A fusible link normally maintains this check valve off its seat so that it does not close until the occurrence of an elevated temperature caused by fire.

Abstract: A carburetor equipped with an auto-choke device is disclosed wherein according to one embodiment a leak valve is disposed in a negative pressure chamber of a diaphragm device adapted to operate by a negative pressure in a suction passage downstream of a throttle valve so as to open a choke valve in said suction passage to a predetermined degree of opening (complete explosion opening) after an engine has rotated by itself, and when the diaphragm has executed a predetermined shift, the leak valve is opened, and simultaneously, the downstream of the leak valve is brought into the atmospheric pressure for engine temperatures below a set value and into the same negative pressure as that of the negative pressure chamber for engine temperatures at and above the set value, whereby the operating stroke of the diaphragm is changed-over in two stages in dependence upon the water temperature or oil temperature, and the complete explosion opening of the choke valve is changed-over in two stages so that it may become narro

Abstract: A hydraulic cylinder arrangement of the type wherein the opposite ends of a cylinder are connected selectively to either a pump or sump by a control valve. Each end of the cylinder is provided with a pair of oppositely acting, uni-directional check valves, each connected to a port on the control valve by an individual conduit. The four check valves are so arranged that all the fluid discharged from either end of the cylinder in response to the reciprocation of the piston therein is constrained to flow to sump before it is pressurized and returned to the cylinder.

Abstract: A device for the raising and lowering of a tilting cab of a road vehicle, with respect to the chassis of the vehicle on which the cab is pivoted, permits both lifting and lowering to take place under the control of a manual pump. The cab can also be left in a "floating" condition, when lowered, for the absorption of vibration which would otherwise be transmitted to it by the chassis during running, and in the "floating" condition, exceeding of a certain amplitude of relative movement between the cab and the chassis causes hydraulic clamping of the cab with respect to the chassis. A mechanical locking device may additionally be provided for locking the cab to the chassis in fully lowered condition, and the hydraulic system may permit acceleration of the downward movement of the cab, during lowering, for better engagement of such mechanical locking device.

Abstract: A damping device in pressurized fluid cylinders, especially in hydraulic cylinders, for end position damping of the piston stroke. The device comprises a closure member connected to the piston and adapted to enter during a damping process into an outlet opening in front of the piston. A ring, serving as a non-return valve, is arranged with an axial play in an annular groove so as to choke the flow of pressurized fluid through the annular passage between the wall defining the outlet opening and the closure member, while permitting a fluid flow in the opposite direction during the return stroke of the piston. According to the invention, the ring has a cross-section permitting at least a radial deformation, and circumferentially distributed by-pass openings located in the region of the inside of the annular groove so as to permit said fluid flow during the return stroke of the piston.

Abstract: A fluid pressure cylinder which utilizes a standardized housing, piston and piston rod for forming a cylinder assembly either with or without bumpers. The bumpers can optionally be positioned on the piston when desired, with the overall assembled length and maximum stroke of the cylinder being identical whether provided with or without bumpers. The piston is selectively mounted on the piston rod in one axial orientation if bumpers are not used, and the piston is reversed and mounted on the piston rod in the opposite axial orientation when bumpers are used.

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: Method and device for braking the speed of movement of the piston of a plunger-cylinder device by choking the outlet of medium on the side of the piston approaching the end wall of the cylinder and by coupling the piston rod of the cylinder with the piston of a second plunger-cylinder device.

Abstract: A hydraulic percussive machine in which a piston is caused to reciprocate in a cylinder including a cushioning flange on the piston, a first space in which the flange normally moves, a second space into which the flange can move on overtravel of the piston during the power stroke to trap fluid into the second space so that a dashpot action takes place, and co-operating timing grooves and ports on the piston and the cylinder to connect the first space to a low pressure zone in the system.

Abstract: A machine for clipping strip material including a blade operated in a cyclic manner having a cutting stroke and a return stroke. A toggle linkage including a toggle bar effecting one blade cycle by moving in a lengthwise direction with the blade being reciprocated by toggle linkages moving through an upright position to a position oppositely inclined to their starting position. The toggle bar is coupled to an actuating piston rod of a pneumatic cylinder. End caps of the cylinder are recessed to receive piston extensions during final stages of piston travel for cushioning purposes. Seal means engage each piston extension during the later stage of piston travel to trap air between the advancing piston and the end cap. Accordingly, blade and toggle assembly inertia is dissipated in the compression of trapped cylinder air. Exhaust means within each of said end caps is valve controlled to release cylinder pressure at a desired pressure braking the latter stages of piston travel.

Abstract: An anvil roll has a steel core and an outer portion of polyurethane. The roll is slightly rotated after a number of veneer clipping operations by a clutch which drives the roll after the roll is pushed by a knife down away from arcuate braking surfaces. An airbag normally urges the roll into engagement with the braking surfaces and is collapsed during adjustment of the roll. Operation of the clutch is prevented during the clipping operation. A double-acting cylinder drives the knife through a toggle joint linkage, and cushioning cylinder means aid in overcoming inertia of the knife at the start of a clipping cycle and also cushion the return of the knife. The cylinder has poppet check valves to rapidly admit air thereto.

Abstract: A cushioning device, for cushioning the impact between a closed end portion of a cylindrical member of a hydraulic jack and an end portion of an inner member reciprocable within the cylindrical member, including a blind bore provided in one of the end portions, an elongated plunger attached to the other end portion for telescopic entrance into the blind bore as the end portions approach each other and an orifice for metering fluid forced from the blind bore by the progressive ingress of the plunger into the bore.

Abstract: A pressure balanced hydrostatic slip bearing as shown for use in guiding and restraining a test table which is shaken in longitudinal direction to vibrate or shake test objects, and also which may be shaken in vertical direction. The slip bearing controls lateral position of the table during operation. A second slip bearing applies a constant compressive preload force to one side of the table and the other pressure balanced bearing is a constant displacement bearing positioned on an opposite side of the table to react lateral forces which may be imposed on the table during operation.

Abstract: A pneumatic impact device comprising a housing, a drive piston and a piston rod. At the forward end of the piston rod there is attached a tool intended for metal working like punching, cropping or forging. The housing contains a drive chamber, an air charge chamber, a reverse chamber and a retard chamber. The piston rod is provided with two forward-facing, annular shoulders one of which constitutes a reverse piston for working in the reverse chamber and the other a retard piston for working in the retard chamber. For being protected from impact strains, the drive piston is longitudinally displaceable relative to the piston rod. During the working strokes, the drive piston cooperates with a backwardly facing shoulder on the piston rod, but just before the latter reaches the point where the tool hits the billet to be worked, the drive piston is stopped in the drive chamber and is thereby separated from the piston rod shoulder.

Abstract: A piston and cylinder actuator is disclosed embodying means to control the acceleration and deceleration of the piston as it approaches the ends of its stroke. Such actuator is also disclosed as an intermittent drive for a machine system in which at least part of the drive connection is provided by a friction drive. The acceleration and deceleration control is arranged to prevent slippage in the drive. The acceleration and deceleration control includes a land positioned on each side of the piston, each formed with a plurality of axially spaced orifices. As the piston approaches one end of its stroke, one land projects through an associated seal which operates to progressively isolate the orifices from the main chamber to control deceleration. Such orifices are progressively uncovered as the piston moves away from its end position, and in one embodiment provides controlled acceleration.

Abstract: A hydraulically controlled pneumatic swinging door operator comprising a pneumatic cylinder with a piston therein, a continuous loop connected to opposite sides of the piston and entrained at its ends over sprockets, one of which makes driving or driven connection with a door, a passive hydraulic system including a cylinder and a piston, the piston of which is carried by the side of the loop opposite the side carrying the pneumatic piston, and passage work in the hydraulic system for controlling the flow of hydraulic fluid in said cylinder from one side of the hydraulic piston to the other side.

Abstract: A piston-in-cylinder type pneumatic actuator is provided with an automatic cushioning facility to prevent the piston from returning to its fully retracted position at velocities exceeding a predetermined maximum velocity. Integrally-housed in the actuator is a velocity transducer arranged to sense the pressure in a cylinder working volume, which pressure is related to the piston velocity and is used to control the operation of an exhaust valve operable to vary the rate of flow of gas from the cylinder thereby to vary the rate of return of the piston.