Abstract: 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.

Abstract: The invention herein described is an endoprosthesis intended to replace a resected portion of bone and joint. The invention can be non-invasively, manually operated to lengthen a patient's limb both intraoperatively and postoperatively. It includes bone anchoring components for anchoring to a first and second long bone, a joint to replace the function of an orthopedic joint, and a purely mechanical lengthening mechanism which can be located and operated manually by an operator by pressing on skin of a patient without requiring a surgical incision. An alternative embodiment of the invention describes a similar extendable endoprosthesis which is unlocked by an operator by pressing on skin of a patient and the limb is subsequently pulled or pushed by the operator to change its length. The invention does not need or include any magnets, electric motors, electric current, application of heat or a fluid displacement (hydraulic) system.

Abstract: A plunger assembly for a power steering system comprises a plunger and a tappet. The plunger is disposed within and longitudinally movable along a plunger passageway in a housing of the power steering system. The tappet is disposed within and longitudinally movable along a port defined by the housing. The port is disposed at an angle with respect to the plunger passageway within the housing. The port communicates with the plunger passageway and an area exterior of the power steering system. A power steering system and method of setting the same are also disclosed.

Abstract: A system for providing pressure/load control at an end stroke stop is provided. The system includes an actuator housing having an end stroke stop and a first actuator housing side, an actuator piston provided in the actuator housing, wherein the actuator piston is movable along a longitudinal axis (A), the actuator piston having a first piston portion perpendicular to the longitudinal axis (A), and means for regulating the pressure/load control at the end stroke stop provided in the first piston portion, wherein the means for regulating the pressure/load control at the end stroke stop is configured to move from a closed position to an open position when in contact with the first actuator housing side.

Abstract: An improvement to the component based hydraulic systems is an integrated electro-hydraulic actuator (EHA) that contains all components necessary to achieve power up, gravity return actuation of a lift mechanism such as the forks of a pallet truck. Further, improvements to known power-up, gravity-down component-based hydraulic circuits are described herein. The improvements provide for power up, gravity return functionality with fewer components as compared known systems. Finally, a method for controlling the EHA and/or hydraulic circuits described above is detailed herein and provides a user with maximum control of a lift mechanism during lower or “down mode,” but also provides for the least amount of energy consumption by the actuator.

Abstract: A fluid-operated circuit for setting the top dead center and the bottom dead center of the punch actuation cylinder in punching machines comprises a first copying distributor which distributes pressurized fluid, which has a spool at one end and can be connected in output to the upper section of the chamber in which the actuation cylinder slides and in input to a first pump for feeding low-pressure fluid and to at least one first fast-acting electric valve element; the spool can be pushed into position by contact by a corresponding setting element with continuous micrometric movement.

Abstract: A pneumatic cylinder for actuating fume extraction valves in fume and heat extraction plants has a piston (2) that may be actuated from both sides with at least one working surface and that can be made to slide by pressurised air in a cylinder (1) with at least one working chamber (4), as well as an energy accumulator with regulating means. The regulating means can be controlled by control means to open or keep open the fume extraction valves. In order to obtain a compact pneumatic cylinder for a fume and heat extraction plant which is easy to install, a storage chamber in which air or pressurised air is stored as compressible pressure medium is provided as energy accumulator. The storage chamber is in communication with a compression surface (7) of the piston (2), at its side opposite to the working surface (7), so that pressure medium may flow between the storage chamber and the compression surface (7).

Abstract: A firewood splitting machine is composed of a support frame, a cutter mounted on one end of the support frame, an oil pressure cylinder mounted on another end of the support frame, and an oil injecting device mounted in the support frame. The oil pressure cylinder consists of a cylindrical body, a piston, a rod member, a subsidiary piston, and a subsidiary rod member. The piston is located in the cylindrical body such that an oil pressure space is formed between the piston and a rear end cover of the cylindrical body. The rod member is fastened at one end thereof with the piston such that another end of the rod member is jutted out of a front end cover of the cylindrical body. A pivoting hole is extended along the direction of the longitudinal axis of the rod member such that the pivoting hole is in communication with the oil pressure space.

Abstract: A pneumatic or hydraulic cylinder assembly (10) includes a cylinder (10), a piston (12) axially slidable within the cylinder (10), and structural elements are disposed within the cylinder (10) to issue a piston (12) position signal in response to the piston reaching a predetermined position.

Abstract: A device capable of comparing the travel position of an output shaft of a diaphragm actuator or cylinder with the current level of an electronic input signal and further being capable of manipulating the pressure of a separate air signal piped to a diaphragm actuator or cylinder in order to correct any imbalance between such a shaft position and a given electronic signal level, including the ability of varying its dynamic response through built in adjustments.

Abstract: A hydraulic power drive unit (36) including a linear hydraulic piston cylinder unit (64) with a set of longitudinally spaced gear teeth (84) in the form of a rack. A pinion gear (86) is operatively engaged and driven by the rack (84). A differential which may include a carrier (102), planet gears (108, 110) and sun gears (120, 122) may be driven by the pinion gear (86) to selectively transfer drive power to two separate rotary drive outputs (38, 40). A switching valve (160) may be provided which is responsive to a reversal of hydraulic supply pressure. Operation of the switching valve (160) may be limited by mechanical interference between an inhibit dog (181) and a cam surface (196) on the carrier (102). The carrier (102) may also include a separate cam surface (140) positioned for actuation of separate electrical switches (146, 148) in order to monitor position of the drive outputs (38, 40).

Abstract: A pressurized fluid actuation system as provided for a surgical instrument. The system includes a double-acting fluid pressure actuator with an extension chamber and a retraction chamber separated by a piston for engaging a component of the instrument. An operating lever is pivotally mounted to the piston. The operating lever is also pivotally connected to a servo valve that has a valve spool. The valve is connected to a source of pressurized fluid and has first and second return ports for venting the fluid. The actuator extension and retraction chambers are connected with the valve for each communicating with the pressurized fluid source and with one of the return ports in response to the position of the valve spool. The system includes a feedback line communicating between the extension chamber and the valve to apply a force to the valve spool in one direction when the extension chamber is pressurized.

Abstract: A wood splitter comprises a fixedly mounted splitting wedge 2 and a pressure plate 4 driven by a hydraulic ram 5,6 so as to feed pieces of wood 3 onto the wedge. Hydraulic fluid is delivered to the ram through the intermediary of a hydraulic-pressure control valve 14. Feed movement of the pressure plate is initiated only when the hydraulic pressure applied to the valve rises above a predetermined value. The pressure plate is returned to its starting position by a spring 23 when the hydraulic pressure falls below the predetermined value.

Abstract: A position-controlled actuator including a double acting pneumatic actuator, a selector valve which causes function of the actuator, a comparator which controls the action of the selector valve in response to a comparison between an input signal and a signal indicative of the position of the actuator, and a feedback link which provides the comparator with a signal indicative of the position of the actuator. The actuator would have oscillation damping seals such as seals of VITON brand fluorocarbon rubber.

Abstract: The mechanism has an actuator provided with a piston, a servo control valve which is actuated by electric input and output signals for supplying working fluid to the actuator and exhausting working fluid from the actuator, a slider which closes an oil passage from the servo control valve to the actuator and which temporarily engages with the piston of the actuator via a link mechanism, when a system for transmitting the input and output signals or the servo control valve breaks down, and a centering valve which is constructed in one body with the slider and which stops supply and exhaust of working fluid after the actuator has been returned to its neutral position by supply of working fluid to the actuator when a system for transmitting the input and output signals or the servo control valve breaks down.

Abstract: An in-line hydraulic dashpot is disclosed that effectively decelerates the iston of a power cylinder by controllably choking off the oil which is providing pressure to the piston. The in-line hydraulic dashpot of the invention includes a valve spool member movable between an open and closed position along a fluid flow path that supplies oil to the power cylinder. An actuator rod is cooperative with the valve spool member and the piston shaft of the power cylinder to move the valve spool member between its open and closed positions. The in-line hydraulic dashpot eliminates the clashing of mechanical parts and therewith eliminates the noise that would otherwise be generated thereby. The in-line hydraulic dashpot of the present invention makes possible the adaptation of a fixed stroke power cylinder to applications that call for a variable stroke length.

Abstract: A single acting, spring return hydraulic cylinder suitable for use as an actuator of a portable cutter or the like. A piston slidably received in the cylinder has formed therein a hollow and a hole communicating the follow with a fluid chamber on one side of the piston. For discharging the fluid from the fluid chamber through a discharge port in one end of the cylinder upon full extension of the cylinder, a release valve mechanism is provided which comprises a valve stem slidably extending through the hole in the piston into the hollow in the piston, and a valve head formed on one end of the valve stem and received in the hollow in the piston. One or more expansions are formed in the piston for the admission of the pressurized fluid from the fluid chamber into the hollow in the piston during piston travel away the one end of the cylinder.

Abstract: A hydraulic drive mechanism in a machine tool, in which both the ends of a feed rod connected to frontward/reverse rotation drive means are journaled in bearings by a base frame and a cylinder frame, a feed plate is threadably mounted on the feed rod between the cylinder frame and the base frame, reciprocatively movable members are connected to the rods of double-acting cylinders, the primary chambers and secondary chambers of these cylinders are respectively connected to the primary chambers and secondary chambers of double-acting drive cylinders being oil pressure sources for the first-mentioned cylinders, the drive cylinders are fixed to one surface of the cylinder frame and have their rods inserted through holes provided in the cylinder frame, the distal ends of the rods of the drive cylinders turnably connected to the feed plate, and the other surface of the cylinder frame is confronted to the base frame with a proper spacing therebetween.

Abstract: A press which is particularly adapted for pressing casings, cable shoes or such items onto a body, having a steering element supported against a drive which on one hand is connected at the press plunger, and on the other hand, is connected with the cylinder, and which upon movement of the press plunger in the working direction, moves the steering element at a fraction of the speed of the press plunger, whereby a locking device, actuated by the workpiece to be pressed, connects the steering element with the press plunger in such a way that the steering element moves with a speed equal to that of the press plunger and that there is an arresting device at the steering element which, in a predetermined position of the press plunger, blocks pressure medium feed to the work room of the cylinder.

Abstract: A pneumatic reciprocator includes a cylindrical air cylinder concentrically mounted within a cylindrical manifold. A cylindrical sleeve valve is concentrically mounted for movement along the manifold by a pair of spaced O rings. Two sets of circumferentially arranged air holes in the manifold are alternately covered and uncovered by the O rings as the sleeve valve is moved to selectively pressurize and vent opposite sides of the piston in the air cylinder. Movement of the sleeve valve is controlled by stops on the movable bed of a surface grinder that is controlled by the air cylinder.

Abstract: Miniature engine operated by an expanding gaseous fluid, which comprises a cylinder (18), piston (20) and inlet valve (29), the upper part of the piston (20) cooperating with a radially expansible resilient diaphragm (28), which is secured to the piston (20) and performs momentarily a pneumatic seal-engagement function along the periphery of said cylinder (18) during the gaseous expansion phase.

Abstract: A cylindrical casing accommodates an operator pistion and a power piston separated by a fixed barrier which serves to define with the former a reservoir and with the latter a power chamber. A piston rod affixed to the operator piston extends through the barrier into manual brake actuating relation with the power piston. Hydraulic fluid under pressure is introduced to the reservoir from which it flows through barrier passages, past a check valve, into the power chamber and out through venting ports formed in the piston rod. To apply vehicle brakes linked to the power piston, the operator piston is manually propelled toward the barrier, and the power piston is thus forced away from the barrier by the piston rod, resulting in rapid transfer of hydraulic fluid from the reservoir to the power chamber. The venting ports then close, such that the power chamber is pressurized to exert a brake power assisting hydrostatic force on the power piston.

Abstract: A hydraulic control valve for a single-acting cylinder includes a valve housing having a cylindrical valve bore. A supply port present in the valve housing is in communication with the valve bore, as is a discharge port and a delivery port. A valve pin is slidable within the valve bore between first and second pin positions, the valve pin including a pin groove positionable to establish communication at the first pin position between the supply port and the delivery port to the exclusion of the discharge port. The pin is slidable from the first position to the second position to establish simultaneous communication with the pin groove between the supply port, the discharge port and the delivery port.

Abstract: A locking apparatus for fluid operated valves having a piston connected to the valve actuator which moves in response to applied pressure within a cylinder housing having a cylinder head, a catch block is secured to the piston, and the cylinder head incorporates a catch pin. Pressure applied to the cylinder to open the valve moves the piston adjacent to the cylinder head where the catch pin automatically engages the catch block preventing futher movement of the piston or premature closure of the valve. Application of pressure to the cylinder to close the valve, retracts the catch pin, allowing the valve to close. Included are one or more selector valves, for selecting pressure application to other apparatus depending on the gate valve position, open or closed, protecting such apparatus from damage due to premature closing caused by pressure loss or operational error.

Abstract: A fluid pressure operated device comprises a body adapted for moving an article and carrying magnets coupled to other magnets on a piston movable by fluid pressure in a cylinder. The body also carries spaced magnets and another piston carries spaced magnets. In a start position, one of said body magnets and one of said piston magnets are coupled. During normal operation the body and pistons move to another position in which the one body magnet operates a return sensor to return the device to start position. If an obstacle is encountered, the piston moves to release another sensor to reverse the device for a short stroke where a timer again reverses the fluid pressure to complete the stroke. Engagement with a second obstacle or a repeat engagement with the first obstacle returns the device to the start position and a warning alerts an operator to remove the obstruction.

Abstract: The invention relates to piston and cylinder unit with a regulating valve for controlling the speed of the piston. The regulating valve has an open position in which it allows free passage of a fluid to the piston and a choking position in which it reduces the rate of such flow for influencing the speed of the piston. Furthermore there is at least one sensor responding to a given position of the piston and designed to change over the setting of the regulating valve. The sensor is an inductive, electrical or magnetic contactless sensor. The regulating valve has a setting unit electrically operated by the regulating valve so that the regulating valve is switched between its open and choked positions.

Abstract: A driving apparatus for producing a to-and-fro movement and having four plunger cylinders and four external non-return valves. Such driving apparatus is distinguished by a particularly simple construction.

Abstract: A fluid operated positioning apparatus includes a multi-position valve operated in response to differential pressure in a fluid control circuit. The control circuit includes two adjustable throttles in series, the junction between the throttles being connected to a control device at one end of the valve. Particular relationships for the throttles are disclosed. Other embodiments include additional throttles for improved control with low pressures.

Abstract: A valving mechanism for a cylinder-piston unit wherein the extreme positions of the piston are not positively controlled by a crankshaft or similar device. Inlet and exhaust valves are respectively mounted in a cylinder head and are operated by actuating rods projecting into the path of the piston.

Abstract: A hydraulic controlling and actuating system has a hydraulic source having a high-pressure side and a low-pressure side and a hydraulic actuator connected to a controlled element and having one compartment pressurizable for moving the element into one of its end positions and another compartment pressurizable for moving the element into the other of its end positions.

Abstract: A fail-safe system is used in a control unit for opening and closing guide vanes of a pump-turbine apparatus operable in both of pump operation mode and turbine operation mode. The fail-safe system has a wire carried by a rotatable sheave adapted for transmitting an information concerning an opening degree of the guide vanes, a weight suspended from one end of the wire, an operation rod disposed below and in alignment with the weight in the direction of action of the force of gravity, and a change-over valve adapted to be switched by the operation rod. When the wire is cut off accidentally, the weight drops onto the operation rod to depress the latter to switch the change-over valve so that a servo-motor is switched to make the guide vanes close at predetermined rates of change of the opening degree in respective operation modes.

Abstract: A wheel supported mobile log splitter has an elongated frame supporting a stationary wedge-shaped log splitting element and an opposing movable ram which is connected to the piston rod of a hydraulic cylinder mounted on the frame. The cylinder is supplied with high pressure hydraulic fluid by an engine driven pump which receives fluid from a hydraulic reservoir associated with the frame and is also connected to the reservoir by a line having a high pressure relief valve. Hydraulic fluid is exhausted from the cylinder and returned to the reservoir through a pair of control valves which are coupled together and actuated simultaneously to provide for rapid return of the ram and for minimizing the cycle time to split a log.

Abstract: The invention relates to a compressed fluid saving device positioned between the outlet of a distributor and the admission of a pneumatic jack. The device comprises a valve which is kept open, to allow the flow of driving fluid into one chamber of the jack from the start and right through the stroke, by the exhaust back-pressure escaping from the other chamber of the jack, and acting on the piston of said valve. When the back-pressure disappears, the valve closes under the action of a screw-adjustable spring.

Abstract: Apparatus for producing a reciprocating oscillation of a power output shaft comprises a plurality of peripherally spaced cylinders disposed in generally tangential relationship to the periphery of a cylindrical fluid pressure chamber and connected at their inner ends to such fluid pressure chamber. The gas pressure in such chamber is regulated to maintain a selected value above ambient. Cooperating pistons in each of the cylinders are interconnected by connecting rods to a spoke-like rocker element which is freely oscillatable about the output shaft to which the housing defining the cylindrical fluid pressure chamber is secured for co-rotation. A flywheel mass is connected to the spokes of the rocker element. Inlet and exhaust valves are provided in a cylinder head mounted in the outer end of each cylinder and are operable by contact with the outer face of the respective piston.

Abstract: An apparatus for positioning an adjustable member as a function of a command signal and a control condition, especially for the positioning of a hoisting mechanism on a tractor or the like, comprises an operating circuit and a control circuit. The operating circuit has a bidirectional positionable valve with a valve side and first and second control devices for regulating flow of pressure medium from a supply tank to the adjustable member. The control circuit connects a control pressure medium source to the control devices at first and second junctions and includes adjustable throttles and a flow-regulating valve. A first adjustable throttle is connected between the supply tank and the first junction. The second adjustable throttle is connected between the control pressure medium source and the first junction and in series with the first adjustable throttle.

Abstract: Method and apparatus for producing rotation of a power output shaft comprises a plurality of peripherally spaced cylinders disposed in generally tangential relationship to the periphery of a housing defining a cylindrical fluid pressure chamber and connected at their inner ends to such fluid pressure chamber. The housing is mounted on, and co-rotatable with the output shaft. The gas pressure in such chamber is regulated to maintain a selected value above ambient. Cooperating pistons in each of the cylinders are interconnected by connecting rods to a unidirectional clutch mounted in the fluid pressure chamber on a fixed shaft, thus forcing the cylinders to rotate when pressured gas is introduced in the outer ends of the cylinders. Inlet and exhaust valves are provided in a cylinder head mounted in the outer end of each cylinder and are operable by contact with the outer face of the respective piston.

Abstract: A bathtub elevator consists of a floor frame, two tonglike guiding linkages, a lifting plate and two flexible lifting tubes, which are adapted to be filled with water under pressure. By means of a manually controllable valve, the flexible lifting tubes can be selectively connected to a supply line or to a drain line and can be shut off from both lines. An adjustable automatic elevation-limiting apparatus comprises a shutoff valve, which is incorporated in the supply line and actuated by means of a U-shaped member, which is displaced by the displaceable ends of the guiding linkage when the desired maximum elevation, which corresponds to the height of the bathtub, has been reached.

Abstract: In a pneumatic nailer using compressed air for driving nails, a work chamber contains a drive piston and is in communication with a storage chamber for effecting the return of the drive piston after it has driven a nail. A valve unit controls the supply of additional compressed air into the storage chamber. A switching element is arranged to react when a predetermined compressed air pressure is exceeded for controlling the flow of compressed air through the valve unit to the storage chamber. The switching element can be a pressure limiting valve. The combination of the switching element and valve unit avoids unnecessary compressed air losses in the higher pressure operating ranges.

Abstract: A remote handling manipulator having a slave arm and a manually operated controller with a grip mechanism, is provided with a force feedback system to impose a force resisting operation of the grip mechanism related to a load experienced by the slave arm. A jaw mechanism of the slave arm is operated by a pressurized fluid, and in the system the pressure of the fluid and the effort exerted by the grip mechanism are compared to produce an error signal used for regulating the force applied to the grip mechanism.

Abstract: A device for the positioning of an adjustment element dependent upon a desired level and the actual level, particularly for the adjustment of a hoist gear train of a tractor, a combine or the like, has an operating circuit 10, which has a multi-way valve 3 pressure-operated in two directions, and a control circuit 29 for the operation of the multi-way valve, connected to a pressure source 19, which is connected to two control devices 11, 12 of the multi-way valve. Circuit 29 has two adjustable series-connected throttles 22, 24, connected to one of the two control devices. The first throttle 24 is also connected to a tank 7 and the second throttle 22 is also connected to pressure source 19. Both throttles have the same maximum flow-through cross section, and are adjustable in the same manner. Third and fourth throttles 27, 28 are provided, one being between the pressure source and control device 11, and the other between the control device and tank 7.

Abstract: In an apparatus for forming leak-proof joints between tubes and a tube sheet by the internal application of hydraulic swaging pressure, the flow of relatively low pressure fluid from a pressure source to an intensifier is permitted or interrupted by a control valve. During a prefill period, a prefill valve causes the low pressure fluid to bypass the low pressure input side of the intensifier and flow directly to the high pressure side and then to a mandrel. Thereafter, the low pressure fluid is caused to enter the low pressure side of the intensifier to increase the pressure in the mandrel during a swaging period. A pressurization sensor, which is connected to the input and output sides of the prefill valve, contains a piston which is movable in response to the difference in the pressures at these two points to produce a termination signal which, after a delay, actuates the control signal at the end of the swaging period.

Abstract: A cyclic or periodic event timing system for use in conjunction with a pressure fluid control circuit includes a cylinder and piston type actuator comprising a differential area piston which is exposed to fluid pressure from a flow conduit on opposite sides of a flow restricting orifice in the conduit or a branch portion thereof. The actuator piston includes a rod portion which is extended in one direction in response to an unbalanced pressure force on the piston. On the extension stroke, the actuator opens a valve to effect flow in the conduit resulting in a reduction in pressure which is sensed in the cylinder chamber exposed to the larger piston fluid area. The actuator piston then returns to an initial retracted position in response to an unbalanced pressure force.

Abstract: In a device for achieving speed control of a cylinder piston in relation to the cylinder, or vice versa, flow control means (12, 32) are utilized, and also cam profiles (15, 16 and 26, 27). The flow control means are composed of two constant flow valves (30a, 30b and 31a, 31b) which determine the flow for one each of the directions of the piston or the cylinder. The cam profile means have a first cam profile (15 and 26, respectively) which is connected when the piston (6) or the cylinder (5) moves in its first direction, and a second cam profile (16 and 27, respectively) which is connected when the piston or cylinder moves in its second direction. The flow control valves are controlled mechanically by the respective cam profiles via its respective control input (12c', 12c") and determine a flow for the piston or cylinder which is dependent on the controlling but independent of the load on the piston or the cylinder.

Abstract: In an apparatus for forming leak-proof joints between tubes and a tube sheet by the internal application of hydraulic swaging pressure, the flow of pressurized fluid from an adjustable pressure reduction valve is permitted or interrupted by a control valve. An actuator moves the control valve between its flow permitting and interrupting positions in response to a control signal. In the sensor, which is connected to the input and output sides of the control valve, a piston is movable in response to the difference in the input and output pressures to produce the control signal when a predetermined comparative pressure relationship exists.

Abstract: A pneumatic reciprocating mechanism comprising a working member (11) reciprocably powered in a housing (10) and forming together with a vibration absorbing reaction support member (12) and an elastic seal element (47) a working chamber (49) which is supplied with pressure via an air feed valve (54,55). The latter is positively coupled to the working member (11) and controls the air flow through openings (54) in the reaction support member (12) in response to the relative positions of the working member (11) and the reaction support member (12).The elastic seal element (47) is associated with the working member (11) and has an annular valve collar (48) which is arranged to establish sealing contact with a diverging peripheral wall (52) of the reaction support member (12) by radial expansion due to the air pressure in the working member (49).

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: A multi-segment farm implement flexible tool bar or frame is provided with a hydraulic system including a rotary flow divider for raising and lowering each segment of the sectional frame in synchronous movement with the other sections. A mechanical linkage associated with a ground wheel positioning cylinder also activates the hydraulic fluid control system limiting the downward movement of the implement mounted to the sectional frame on its supporting gear.

Abstract: A forward motion arresting means is added to a fluid powered lance to reduce the harmful effect of the stopping of the lance forward motion. A plug member mounted on the lance mates with a body member within the housing to prevent fluid flow and reduce the lance forward motion. Rearward motion arresting is achieved by the addition of a reservoir portion which acts as a hydraulic stop in conjunction with the lance piston.

Abstract: An apparatus for controlling the movement of a fluid-actuated hydraulic cylinder. A pumping mechanism is provided to pump fluid into the hydraulic cylinder; and a tank receives the fluid expelled from the hydraulic cylinder. A reversing valve between said pumping means and said hydraulic cylinder means controls the flow direction of the fluid into and out of the hydraulic cylinder and a valve mechanism between the pump means and the hydraulic cylinder, and operatively connected to the hydraulic cylinder, controls the fluid flow rate into and out of the cylinder corresponding to the motion of the hydraulic cylinder. One embodiment of the invention is specifically designed to power the main drive gear of an apparatus for stacking battery plates and separators.

Abstract: In a hydrazine powered engine, an intake valve arrangement for positively controlling the opening and closing of the poppet valve in a hot gas cylinder, the poppet valve being operated by the piston and gas pressure only. The poppet valve uses a pneumatic "spring" which holds the poppet valve against the piston while the valve is opened and closed. To accomplish this, a poppet valve is slidably mounted in a "pneumatic spring" chamber which reaches a pressure approaching the gas supply pressure and, during the opening of the valve, the "spring" chamber retains enough pressure to hold the poppet valve onto the piston. In addition, the bottom of the poppet valve can have a suction cup type configuration to hold the poppet valve on the piston during the down stroke.