Abstract: A pneumatic brake booster having a right casing (10) divided in a leaktight fashion by a first moving partition (12) into a front chamber (14) and a rear chamber (16). The front chamber (14) being permanently connected to a source of low pressure (V) with the rear chamber (16) being selectively connected to the front chamber (12) and as source of high pressure by a three-way valve (40) operated by an operating rod (34). A three-way and two position solenoid valve (68) has a first inlet connected to the source of low pressure (V), a second inlet connected to a source of high pressure (A) and outlet connected to the rear chamber (14). A second moving partition (54,54') divides the rear chamber (14) into a working chamber (16) and a control chamber (50,50') with the outlet of the solenoid valve (68) being connected to the control chamber (50,50').

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 control and safety system for coordinating movement of multiple hydraulic cylinders to reciprocally rotate a truck-mounted refuse compacting arm. The system includes a logic board controller in communication with a cam and switch arrangement mechanically linked to the rotating arm. Signals from the switches indicate the position of the arm to the logic board which responds by operating directional control valves to regulate movement of the cylinders. A pressure switch is activated to rotate the arm in the opposite direction if the arm is prevented from reaching a limit switch.

Abstract: A cylinder positioning control apparatus designed to effect positioning of a cylinder by learning control that uses not only an overrun distance but also a cylinder speed as input data for control. The apparatus has a device for taking in a displacement x and speed V of a cylinder, a device for calculating a predicted overrun distance y.sub.i for the present drive from a predicted overrun distance y.sub.i-1 in the preceding drive, a cylinder speed V.sub.i-1 at the time of outputting a braking signal during the preceding drive, and a speed V.sub.i of the cylinder being driven, a device for judging whether or not a condition to be satisfied to output a braking signal is satisfied, and for outputting a braking signal when the condition is satisfied, a device for taking in a displacement x.sub.bp and speed V.sub.bp of the cylinder when the braking signal is output, a device for taking in a displacement x.sub.stop of the cylinder when it has stopped, and a device for calculating a predicted overrun distance y.sub.

Abstract: Pressure medium pliers for clamping rings, comprising a pressure medium connection and a pressure medium valve connected thereto, at least one piston controlled by the pressure medium valve, a traverse member drivable by the piston and pivoted pliers members at the inner lever ends of which the traverse member engages for pivoting them, the pressure medium valve having a valve pin which is shiftable in traverse direction of the movement of the piston and operatable by a release trigger, the valve pin blocking the connection of the piston with the pressure medium connection and connecting it with a lower pressure level in a rest position and blocking the connection of the piston with the lower pressure level and connecting it with the pressure medium connection in a working position being reachable by operation of the release trigger, a switching bar which is held in a slideway movable in the direction of the piston and which is mechanically biased by a spring towards the valve pin, the switching bar having a

Abstract: A multi-stage hydraulic ram assembly for the accumulator drive system of an elevator assembly includes a plurality of piston-cylinder arrangements connected hydraulically in parallel and mechanically in series. The piston-cylinder arrangements are disposed in substantial side-by-side relationship, constituting adjacent or successive stages of the ram assembly. A bracket is fixed to one of the cylinders and is slidably connected to the adjacent cylinder, for interconnecting adjacent cylinders of the piston-cylinder arrangements, and a drive system is provided for operating the ram assembly. Steps are taken to control the direction and speed of movement of adjacent stages of the assembly, and to ensure that all of the stages of the assembly move at substantially the same speed.

Abstract: A twin post, telescoping jack hydraulic elevator system has a pair of dynamic sensors to determine when the jacks are out of synchronization, by determining any relative differences in height between the two intermediate cylinders. The elevator also includes static sensors to determine if one or both intermediate cylinders are more than a predetermined distance away from their normal positions when the car is stopped at each floor. The controller actuates a resynchronization if the distance between the intermediate jacks exceeds a first threshold, and shuts down the elevator if the distance exceeds a second threshold or if resynchronization demands are issued too often. Preferably, the static sensors are positioned to detect the seal housing at the top of the intermediate cylinder, which projects outwardly from the cylinder.

Abstract: A stepping actuator having a housing containing two linearly reciprocating members independently and axially slidable, and a common rotating member passed through them. One of the housing and linearly reciprocating members has endless circulating grooves formed by tilted grooves interconnected by circumferentially extending grooves while another one of them holds projections adapted to fit in the circulating grooves. The circumferentially extending grooves have a circumferential length equal to a circumferential length of an opposite tilted groove corresponding to another of said slidable reciprocating members. The linearly reciprocating members and rotating member are linked together by a coupling that transmits the rotary motion while allowing free axial motion.

Abstract: A reciprocating floor conveyor has at least three groups of one or more individually reciprocatable slat members. A drive engages each slat group and moves more than half of the slat members simultaneously in a conveying direction and moves the remainder of the slat members in the opposite direction at least at about twice the rate of speed. The drive includes a fluid pressure source, a flow divider connected to the fluid pressure source which provides a separate, equal rate of flow for each slat group, a separate extensible fluid driven cylinder for reciprocation of each slat group that is connected to a separate flow from the flow divider, a direction valve for each fluid driven cylinder which controls fluid flow into and out of the cylinder, and an unloading valve communicating with the interconnected rod sides of the fluid driven cylinders.

Abstract: A device for controlling a pneumatic cylinder device, being of a double cylinder construction comprising an outer cylinder and an inner cylinder sealably fitted in the outer cylinder to slide along the outer cylinder. In the inner cylinder, a piston with a valve at one side thereof or valves at both sides thereof is slidably disposed. To control the valve or valves, an adjusting rod is provided which is slidably and rotatably disposed in the piston and its piston rod and adjusted by an operating lever. Alternatively, the double cylinder construction comprises a pair of cylinders disposed axially in parallel to each other. In the cylinders, pistons are disposed, one of which has a valve at one side thereof or valves at both sides thereof. The cylinders are communicated with each other by a communication construction having a communication adjusting groove and an adjusting lever for adjusting the communication area of communication adjusting groove.

Abstract: A hydraulic system includes a hydraulic pump which provides pressurized fluid at an output port as a function of pressure in a load sensing port, a hydraulic reservoir, and a load pressure sensing line connected to the load sensing port. A solenoid operated implement control valve controls fluid communication to and from a hydraulic function such as a cylinder. A supply control valve has a first position wherein the reservoir is communicated with the load sensing port and a second position wherein the pump output port is communicated with the load sensing port. A spring urges the valve member to its first position, and a solenoid is energizable to move the valve member to its second position. The solenoid is energized when the implement control valve is activated so that the supply control valve communicates pump pressure to the load sensing port and the pump will operate at full capacity whenever the second hydraulic function is operated.

Abstract: Single or multiple flexible robotic manipulator trunks can be made from individually activated, three degree-of-freedom, flexible robotic links. Three dimensional positioning and orientation of the distal end of each link is achieved exclusively by elastic deformation of the flexible link assembly without revolute or prismatic joints. The activating bending and torsional moments required for such a positioning are generated by the antagonistic action of a plurality of prestressed, inflatable, laterally bendable and axially extensible tubular actuators with the anisotropic, circumferentially reinforced walls. The positioning motion, working forces and manipulator arm stiffness are all controlled by asynchronously modulated pulse streams which regulate the distribution of energy from a common source of fluid under constant pressure.

Abstract: Hydraulic hammers are normally controlled by an actuating valve which controls the flow of fluid from a source of pressurized fluid to the hydraulic hammer. During certain periods of operation, the actuating valve totally blocks communication of fluid to the hydraulic hammer, thereby causing the fluid from the source of pressurized fluid to be expelled through a relief valve. The subject hydraulic hammer and control arrangement therefor includes an accumulator for storing the pressurized fluid from the source of pressurized fluid during periods of fluid blockage by the actuating valve and for supplementing the flow of fluid from the source of pressurized fluid when the actuating valve is communicating pressurized fluid to the hydraulic hammer. This increases the overall efficiency thereof.

Abstract: A seawater hydraulic rock drill having a trigger which when engaged by a diver allows pressurized seawater to be directed through an open supply poppet valve assembly into a drive chamber having a plunger. The pressurized seawater drives the plunger into a piston, an anvil, and a drill bit creating a percussive impact into a rock surface breaking up the rock surface. At the same time pressurized seawater exits the drive chamber through an orifice into a reversible seawater hydraulic motor which rotates the drill bit thereby pulverizing the broken rock. As the plunger approaches the end of a drive cycle, the supply poppet is pressurized closing the supply poppet valve assembly and cutting off the flow of seawater to the drive chamber. Pressurized seawater then drives the piston and plunger to their initial positions, the supply poppet valve assembly opens, and the cycle is repeated.

Abstract: A hydraulic cylinder-piston unit comprises primary cylinder-piston unit with an integrated position regulation and with a primary cylinder and a primary piston movable in the primary cylinder, two displacement chambers in the primary cylinder and including two displacement pistons, a displacement piston rod connecting the displacement pistons with one another, and a separating wall, and differential cylinder-piston unit formed by the primary piston and having a differential cylinder provided with working chambers.

Abstract: A boom and bucket system for a loader includes a bucket leveling valve which maintains a desired orientation of the bucket as the boom is raised or lowered. A hydraulic circuit automatically and selectively supplies fluid for bucket leveling from boom cylinder return flow, from a pump, or from both in varying proportions.

Abstract: A hydraulic cylinder comprising a hollow sleeve, having inserted in it, a hollow piston rod. The hollow sleeve further contains an opening allowing hydraulic fluid to pass therethrough and into the hollow piston rod. At the end remote to the opening, a mounting mechanism is contained. On the end proximate the mounting mechanism, a fluid outlet is contained. In use, hydraulic fluid passes through the opening of the hollow sleeve, into the piston rod, and out of the piston rod proximate the mounting mechanism.

Abstract: A parallel translation mechanism, when connected between a first element and a second element, maintains the relative direction between the two elements constant when one of those elements is moved relative to the other. The mechanism is in part formed by first and second rigid elongated members which are pivotally connected together and are pivotally connected by the end of the first elongated member to one of the elements. A first portion of an extendable member is connected between the one of the elements and the second elongated member, and a second portion is connected between the other element and the second elongated member. The other element is also pivotally connected to a position on the second elongated member. The three members of the mechanism are connected together in such a fashion that the described relative movement between the two elements is obtained. The mechanism has particular application to forklift vehicles.

Abstract: The working piston (15) in the cylinder (1) is acted upon by pressure fluid only on one side, while the return movement of the piston is produced by reaction forces (R). The pressure fluid feed and the pressure fluid discharge are effected by way of separate conduits (9, 10) so that there is a continuous interchange of pressure fluid in the cylinder (1). When the maximum piston stroke position is reached, pressure fluid can flow out of the cylinder (1), irrespective of the control position of the control device (2). In both limit positions of the piston (15), the movement of the piston is braked by a mechanical damping means (18).

Abstract: A piston type expander/prime mover utilizes a plurality of pairs of cylinders mounted on a rotatable cylinder support. Each cylinder has an open end and a closed end and each pair of cylinders has their open ends disposed in spaced, opposed relationship. A pair of pistons respectively cooperate with the pair of cylinders, and each piston has a connecting rod pivotally secured thereto and projecting through the open end of the respective cylinder. The two ends of the connecting rods are in turn pivotally connected to a lever arm which is secured to the movable element of a first unidirectional (over-running) clutch which has its stationary element secured to a stationary shaft. A first load transmitting element is secured to the rotatable element of the unidirectional (over-running) clutch. Valving is provided in the closed end of each cylinder to permit a charge of pressured gas to be introduced into such closed end as the respective piston approaches such closed end.

Abstract: A hydraulic shock-absorbing jack particularly for use underwater comprises a cylinder 1 in which a piston 20 associated with an actuated rod 23 is slidable. The piston defines within the cylinder a first actuating chamber 6 provided with a first inlet 2 for actuating liquid and connected to an accumulator 7 of elastically variable volume, and a second actuating chamber 8 provided with a second inlet 3 for actuating liquid. The rod is mounted to be slidable relative to the piston such that, in the event of a shock applied to the rod which would otherwise cause an increase in the volume of the second chamber, the rod alone moves relative to the piston without affecting the volume of the second chamber. The rod is provided with an enlarged head 24 located in the first chamber and preventing its disengagement from the piston.

Abstract: A pneumatic valve is disclosed, for controlling the position of a ram in a partly-extended condition. The valve has a combination of rubbing seals and diaphragms, for smooth operation and reliability. A spring-loaded plunger presses the diaphragm against the mouth of a port, to seal off the port. A piston with rubbing seals lifts the plunger from the diaphragm, to open the port. The piston seals rub against plastic, for freedom from water contamination problems, while the diaphragm provides the high integrity seal needed to control the ram position. A particular application of the valve is to the air control of dentist's chair, medical table or medical chair.

Abstract: A tandem brake booster (10) having first (24) and second (28) walls that move in opposite directions within a cavity to produce an output force. A lever arrangement (48) attached to the second (28) wall engages a fulcrum (70) to transfer a force produced by movement of the second wall (28) into the first (24) wall. A control mechanism (72) has a cylindrical body (74) with an annular surface (78) that engages the lever arrangement (48). The movement of the cylindrical body (74) as compared to the output member (41) is a function of the ratio of the distance from the fulcrum (70) to end (46) and from the fulcrum (70) to the annular surface (78), and as such, maximum output travel can be achieved without requiring a corresponding input travel.

Abstract: For reducing the amount of water consumed, supply of water to the cutting head of a cutting machine shall be given free only if different operating conditions are simultaneously occurring. The proposed process contemplates to provide the possibility to supply water to the cutting head only with the rotational movement of the cutting head being switched-on and to give free the water supply only if simultaneously at least one further operating condition such as, for example, a movement of the cutting arm or a movement of the machine is occurring.The apparatus for performing this process contemplates a device for switching-in a water pump, said device being coupled with a device for switching-in the rotational drive of the cutting head.

Abstract: A valve, comprising: a cylindrical casing, closed at its ends by covers, and having axially aligned inlet and outlet chambers midway of its length disposed at right angles to the axis of the casing. Communication between said chambers is controlled by a ported, fluid pressure operated, movable valve plate assembly, including parallel cylinders, each containing a stationary piston connected to the inner end of a pair of axially aligned rods, or guides, fixed at their outer end to the covers. Each rod has a passageway communicating at its inner end with one end of its associated cylinder for supplying operating fluid thereto to bodily reciprocate the valve plate assembly on said rods within the casing. An adjustable collar positions a fixed wear plate in sealing engagement with one side of the valve plate assembly, and a fluid pressure actuated loading ring urges a floating wear plate into contact with the other side of said valve plate assembly.

Abstract: A blanking machine for blanking holes in a sheet of metal in a zigzag fashion comprising a bolster, a pair of rails, fixedly secured to the bolster extending in a direction right angles to the feeding direction of the sheet of metal to be blanked, a lower die set slidably mounted on the rails, a die fixedly secured to the lower die set, an upper die set having a punch mounted thereon opposite the die, the upper and the lower die sets being coupled together, a hydraulic cylinder having a plurality of pressure chambers formed therein, a transmission mechanism connected to a piston rod of the hydraulic cylinder, and a connecting rod for connecting the transmission mechanism to the upper or lower die set.

Abstract: An actuator device for actuating ejector of a scraper comprising a first actuator having a long stroke, a second actuator having a short stroke, said first and second actuators being connected and fixedly secured in series so that the piston rod of said second actuator can be brought into contact with the piston of said first actuator, and valve means which normally permits the communication between the delivery side of a hydraulic pump and a pressure chamber of said first actuator and which also permits the communication between the delivery side of said pump and the pressure chamber of said second actuator when the pressure within the pressure chamber of said first actuator has increased beyond a predetermined value.

Abstract: In an apparatus for driving fastening elements, such as bolts and nails, into receiving material, a first or driving piston is mounted in a first chamber through which it is axially displaceable. A pressure converter arrangement is connected to an inlet to the first chamber for supplying the compressed air required for displacing the first piston for driving in a fastening element. The pressure converter includes a storage chamber, a second chamber in communication with the storage chamber and a third chamber. A double headed piston has one head in the second chamber and the other head in the third chamber. The third chamber has a much greater transverse cross-sectional area than the second chamber. Compressed air supplied to the third chamber compresses air in the second chamber which is directed into the storage chamber. From the storage chamber, the compressed air is charged into the first chamber for driving the first piston forwardly for inserting the fastening element.

Abstract: A high torque hydraulic power plant is operated by electrical power through the use of a hydraulic pump, opposing double-ended cylinders containing double-ended pistons and appropriate cycling valve means. Pressure is maintained in the system by a constant pneumatic force applied to the full piston side of each opposing double-ended piston.

Abstract: A vehicle brake booster and master cylinder assembly has a vacuum suspended booster section which is controlled by movement of the vehicle brake pedal. A hydraulic booster section is in series with the vacuum suspended booster section, and a master cylinder unit is in series with the hydraulic booster section. The assembly is so interconnected that the master cylinder can be operated manually when there is no or insufficient power pressure to operate either booster section. It may also be operated by actuating the vacuum suspended booster section, and, when no hydraulic pressure is available to the hydraulic booster section, this operation may be followed by manual actuation. It may be operated by initially actuating the hydraulic booster section when there is no vacuum available for initially operating the vacuum suspended booster section, followed by manual actuation as needed.

Abstract: A regulator for regulating the output of an output shaft is discosed, the regulator comprising a number of chambers to and from which working medium can be fed and discharged in dependence upon control means to effect axial movement of the output shaft via pressure transmitting elements.In accordance with the invention, the regulator comprises a number of series-connected units, the units providing fixedly spaced walls to define separated chambers through which the output shaft effectively extends, each chamber having at least one pressure transmitting element therein which is connected directly or indirectly to said output shaft. With such an arrangement the or each pressure transmitting element, when activated, exerts either individually or in unison an axial force on the output shaft substantially corresponding to the sum of the forces exerted on the active pressure transmitting elements.

Abstract: A fluid control unit comprising a drive piston having first and second faces and a drive rod. The drive piston has first and second fluid responsive faces exposable to fluid under pressure. The fluid under pressure acting on the first face urges the drive piston in a first direction and the fluid under pressure acting on the second face urges the drive piston in a second direction. First and second overridable detents drivingly couple the drive piston and the drive rod for movement in first and second directions, respectively. The coupling force provided by the first detent varies with the pressure of the fluid to which the first face of the drive piston is exposed, and the coupling force provided by the second detent varies with the pressure of the fluid to which the second face of the drive piston is exposed.

Abstract: A servomotor for power actuation of a mechanical or hydraulic control, for example brake master cylinders for motor vehicles, is disclosed. The servomotor includes a housing in which a power piston separates a low pressure chamber from a high pressure chamber. The power piston being movable from an idle position in response to a pressure difference between the chambers. The pressure difference being controlled by a valve associated with an inlet control member. An auxiliary power member is located in the high pressure chamber. The auxiliary power member has a pressure compartment connectible to an external pressure source. The auxiliary power member is adapted to move the power piston from its idle position irrespective of the establishment of the pressure difference, to permit the servomotor to be used in an automatic or emergency service brake system.

Abstract: Apparatus is provided for controlling the advance of a tunnel drive shield. The drive shield is of the type having a plurality of elongate implements (or planks) which are supported and guided on a frame. Hydraulic rams are provided for moving the planks relative to the frame. The control apparatus comprises hydraulic ram means, which act between the frame and the permanent tunnel lining, and means for varying the pressure of hydraulic fluid applied to said hydraulic ram means. The frame can be advanced by applying hydraulic fluid to said hydraulic ram means and by simultaneously applying hydraulic fluid to at least one of said hydraulic rams. The direction of frame advance is controlled by varying the ratio of the pressures of the hydraulic fluid applied to said hydraulic ram means and to said at least one hydraulic ram.

Abstract: A hydraulic engine having a frame on which a crankshaft is rotatably mounted between a plurality of cylinders. The individual cylinders are rockingly mounted on the frame arranged as opposed pairs of cylinders and their piston rods are operatively connected to cranks positioned 90.degree. apart upon the crankshaft. A power take-off shaft is also journalled on the frame and a drive train operatively connects the crankshaft to the power take-off shaft. The cylinders are connected by a fluid circuit to a motor-driven pump and included in the circuit are individual distribution valves for the cylinders. Operating plungers of the valves are connected by rods to eccentrics carried by the crankshaft and circumferentially positioned to extend and retract the several piston rods in a sequence which will rotate the crankshaft and deliver usable power to the takeoff shaft.

Abstract: A material handling assembly has a frame for attachment to the three point hitch of a tractor. A laterally swingable boom extends rearwardly from the frame and has an upright shaft at its rear end rotatable about an upright axis for suspending a reversible scraper blade whose angularity may be varied as the shaft is rotated. The blade is releasably attached to and tiltable relative to the shaft. All four functions of raising and lowering the frame, swinging the boom, varying the angularity of the blade and tilting the blade are hydraulically controlled. A special four bar linkage coupled with the shaft provides for wide blade angularity adjustment. A fluid bypass arrangement interconnects the swing and angularity functions to accommodate for excessive loads which may be encountered when the attitude of the blade is to be varied in accordance with desired grading operations.

Abstract: In a drill boom pivotally supporting a rock drilling apparatus, hydraulic parallel motion means is provided which includes a hydraulic pilot cylinder for sensing the setting of the elevation angle of the drill boom. During elevating of the drill boom the hydraulic pilot cylinder is furthermore used as an additional elevating cylinder.

Abstract: A folding tool bar for agricultural implements and including a central section and outboard wing sections hingedly connected thereto for movement between extended operative lowered positions where they may follow rolling ground conditions and folded over-center raised positions to reduce transport width. Each wing section is actuated by a two-stage hydraulic cylinder on the central section which cooperates with a crank arm on such wing section during its first stage to apply torque to the crank arm through the medium of a draw link by a pulling action in tension, assisted by a powerful camming action, the two forces serving to raise the wing so that it barely clears the ground at a small angle on the order of 5.degree., thereby enabling the implement to perform a turnabout motion with the tools withdrawn from the ground but with the wing remaining unfolded. An abutment within the cylinder positively terminates the first stage of operation and determines the 5.degree.

Abstract: A rock drilling apparatus comprises a hydraulically rotated drill, a percussion motor having a piston which transfers impact energy to the drill, the piston defining together with the machine housing first and second pressure chambers for receiving pressure liquid to move the piston, the percussion motor having a hydraulic circuit including a high pressure side and a low pressure side, a pressure liquid distributing valve having a control input for receiving a control pressure, the distributing valve being located in the hydraulic circuit of the percussion motor for alternately connecting at least one of the pressure chambers to the high pressure side and low pressure side, respectively, of the hydraulic circuit in response to the control pressure, the hydraulic circuit for rotating the drill being separate from the hydraulic circuit of the percussion motor and including a high pressure side and a low pressure side separate from the high and low pressure sides of the percussion motor, a control valve for cont

Abstract: The throttle of an engine is controlled to maintain its speed substantially constant in spite of variations of load upon it. The illustrated load comprises hydraulically operated equipment in a hydraulic system powered by a pump driven by the engine. Throttle control mechanism comprises a pair of cylinders supplied from fluid pressure in the hydraulic system. Pistons in the respective cylinders are connected by pivots with a control arm linked to the throttle control. When equipment is hydraulically operated from the hydraulic system, the fluid back pressure against the pump increases, this back pressure being greater the greater the hydraulic load. The increased load on the engine from the pump would slow the engine down if its throttle opening were to remain at its original setting.

Abstract: A control system for hydraulic presses comprising a plurality of press rams, an intensifier having a primary chamber which is connected by a supply conduit to a pump, and a valve which is associated with the primary chamber and when open permits the liquid under pressure to return through a return conduit into a reservoir, the primary chamber being constantly supplied by the pump with high-pressure liquid at a constant rate, and the valve associated with the primary chamber being controlled to move in synchronism with the reciprocating motion of the press rams so that it is closed during the forward stroke and open during the return stroke of the press rams.