Abstract: A pneumatic motor for providing bi-directional linear motion including a motor housing having a cylinder bore and a piston mounted on a piston rod positioned in the cylinder bore. The ends of the piston rod extend beyond the ends of the cylinder bore. The cylinder bore has a liner which acts to provide lubrication for movement of the piston in the cylinder bore and to provide a seal between the piston and the cylinder bore. The motor can be used to provide the drive means for a linear motion conveyor.

Abstract: A percussive hydraulic apparatus includes a body inside which is mounted a cylinder in which an impact piston is guided. Fluid distribution providing the motion of the piston is produced by a distributor housed in a distribution box mounted in the body. The cylinder and the distribution box are entirely contained in the enclosure defined by the body, with the cylinder being mechanically supported by one of its ends of the body. The distribution box is mounted coaxial to the cylinder and is mechanically supported thereon. Surfaces perpendicular to the axis of the apparatus, subjected to pressure, are arranged and dimensioned such that the resultant hydraulic forces applied on the cylinder and distribution box during all the phases of the operating cycle thereof are directed in the same direction towards a support located in the body of the apparatus.

Abstract: A hydraulic pressure intensifier includes a supply connection, a return connection, and a high-pressure connection. An intensifier piston assembly includes a high-pressure cylinder with a high-pressure piston displaceable therein and a low-pressure cylinder having a greater cross-section than the high-pressure cylinder, with a low-pressure piston which is displaceable therein. The low-pressure piston is connected to the high-pressure piston and divides the low-pressure cylinder into a first low-pressure chamber on the side of the high-pressure piston and a second low-pressure chamber. A switching valve acts on the second low-pressure chamber with pressure from a pressure source or relieves it of pressure.

Abstract: Adjustable-height column, especially for chairs, includes a guide tube and a pneumatic, selectively blockable piston-cylinder unit for height adjustment located in the guide tube. The piston sealingly subdivides the cylinder into two operational chambers. Beginning at a defined retracted setting of the piston-cylinder unit, the blocking function is compulsorily canceled, in that a fluid flow connection between the two operational spaces is established which overrides the blocking function. An additional spring element is placed in series with the piston-cylinder unit to prevent a sudden collapse of the column.

Abstract: An air driven diaphragm pump having two diaphragms joined by a common control shaft to reciprocate in opposed chambers for pumping material through check valve ported cavities. An actuator valve is associated with the central housing of the pump and includes a valve cylinder within which a valve piston reciprocates. The valve piston is caused to reciprocate by alternate venting of the ends of the cylinder. Air chamber passages are controlled by the control shaft to vent the ends of the valve cylinder. A cylindrical portion of the control shaft includes axial slots for venting alternate ends of the valve piston. Annular channels manifold air to and from the axial slots. Seals of elastomeric annular rings and PTFE cylindrical inner liners bonded to the annular rings are arranged in certain of the annular channels, the sidewall of one of which is relieved outwardly for increased venting air flow.

Abstract: A device for distributing oil under pressure including a head (2) within which, inside a chamber (24), a shuttle (5) slides provided with a shank (5a) sealingly sliding within an end cap (6) and on whose head surface (19) oil at the feed pressure acts coming from a switch duct (18). The head (2) is provided with a feed hole (8) connected to the chamber (24) and is closed at the other end by a shutter (7) connected to a drain hole (9), while the shuttle (5) is provided with an inner cavity (26) and end ducts (25) and it is shaped so as to have in the chamber (24) opposite transverse surfaces (22, 23) whose difference of area in favour of the surface (23) at the end where the shank (5a) is located is smaller than the area of the head (19) of the latter. A hydraulic hammer including the device is provided with a pair of outflow orifices (17, 20) located so that the first orifice (17) is uncovered by the ram (4) at the end of the return travel and the second orifice (20) at the end of the descending travel.

Abstract: A continually operating fluid pressure amplifier having a reciprocating piston system comprising a broad low pressure piston and a narrow high pressure piston, of which the latter, together with its piston cylinder, is arranged as a three-way pilot valve for operating a bistable control valve that controls the reciprocation of the piston system. The control valve has a primary valve slide controlling the said reciprocation and an auxiliary slide operable to open and close relevant conduit connections for initial amplification of the shift control signals governing the operation of the control valve, whereby a very safe operation of the entire system is ensured. Also ensured is a rapid return stroking of the piston system, such that the produced high pressure can be maintained substantially constant.

Abstract: An over-ride valve assembly is mounted between the actuator valve and center section of an air operated double diaphragm pump to provide normal communication between the actuator valve and the center section of the pump during normal operation of the pump. The over-ride valve assembly has internal passageways extending through normally closed valves to both ends of a valve spool within the actuator valve. The valves may be manually opened to restart a stalled pump by momentarily diverting pressurized air from the diaphragm and directing the pressurized air to the ends of the valve spool to reactivate the valve spool and start the pump.

Abstract: The invention relates to a hydraulic striking mechanism including a cylinder, a percussion piston guided therein and a piston return device which is supported on the percussion piston and is displaceable independently thereof and can be connected on its side facing the percussion piston tip alternatingly to a pressure source or a pressure-free return conduit. The piston return device is configured as an annular piston which is freely displaceable along the percussion piston and the cylinder and forms therewith a piston chamber. The percussion piston has an abutment face at its end remote from the percussion piston tip which cooperates with the annular piston for moving percussion piston in the return stoke direction. The percussion piston, together with the cylinder, defines an oil chamber which axially follows the piston chamber in a spaced relationship. The percussion piston is provided with a cylindrical shoulder within the oil chamber which determines its end position during the return stroke.

Abstract: A variable frequency control for a hydraulic percussion actuator includes a piston bore and a valve bore. A piston is axially disposed within the piston bore, while a valve is axially disposed within the valve bore. A first piston biasing member biases the piston in a first direction while a second piston biasing member, which overcomes the bias of the first piston biasing member to move the piston in a second direction. A first valve biasing pin biases the valve in a third direction while a second valve biasing pin overcomes the bias of the first valve biasing pin to move the valve in a fourth direction. A hydraulic valve actuator displaces the second valve biasing pin when the piston is extended in the second direction, and a piston actuator activates the second piston biasing pin when the valve is extended in the fourth direction. A valve response member controls the time required for the valve to be displaced in said fourth direction upon actuation of said valve actuating member.

Abstract: A double acting and at the limit positions automatically reversing pressure intensifier. A case has a first bore hole and a second bore hole. A pressure intensifier piston slides in the first bore hole of the case and subdivides the first bore hole into two low pressure work spaces and is furnished with two flat control grooves at the outer circumference and with two cylindrical bore holes. Two high pressure pistons are solidly mounted to the case for sliding relative to and inside of the two cylindrical bore holes of the pressure intensifier piston. A check valve is disposed in the pressure intensifier piston and connects the two bore holes. A control slider is disposed in the case and furnished with two flat control grooves about at its middle region which connect to respective front faces of the slider via cross bore holes and axial bore holes in the control slider. A wide bypass groove is disposed on the outside of the control slider.

Abstract: A double acting piston and cylinder air motor with pneumatically actuated pilot valves for shifting a directional control valve, where the pilot valves are controlled by pilot ports in the cylinder as they are uncovered by the piston.

Abstract: A double admitting pressure intensifier which automatically reverses at its end positions is provided. The pressure intensifier comprises a pressure intensifier piston and a control slider running parallel to the pressure intensifier piston, each disposed in a bore of a casing. The control slider receives a control impulse only at the end of a stroke in order to maintain the pressure intensifier trouble-free under all conditions. This is assured by disposing two pressure pins of different diameter projection into axial bores of the control slider. The pressure pin with the larger diameter is connected to the feed line or, respectively, to the discharge port depending on the position of the pressure intensifier piston. The pressure pin with the smaller diameter is, on the other hand, continuously connected with the feed line.

Abstract: A reciprocating piston fluid powered motor having fluid inlet and outlet, wherein reciprocation is controlled by a reciprocable valve spool communicating with said fluid inlet and outlet and cooperating with a valve slide shiftable on said valve spool to control reciprocation of said valve spool. A needle valve assembly controls the exhaust rate proportionally to the operative speed of the motor.

Abstract: A hydraulically actuated pumping apparatus including a piston-driven, plunger-type injection pump in combination with a three-way normally closed pilot-operated relay valve, and a variable restrictor adjustable during operation of the pumping apparatus for controlling the flow of a pilot fluid to the relay valve. Pilot fluid is vented from the relay valve through passageways in the plunger of the injection pump at the completion of each pumping stroke.

Abstract: A hydraulically operated impacting device includes a differential piston slidably disposed in a bore, and having an impacting surface and a piston rod facing at the other end a valve sleeve circumscribing the piston rod, there being an annular space between the rod and the valve, the valve having a first and a second position; a first duct leads from a pressure source to the bore and is governed by the valve for acting or not acting on the larger one of the two piston surfaces respectively in the first and second positions of the valve; a second duct leads from the source to the bore for acting on the smaller one of the piston surfaces; a third duct leads from the bore at a location below the valve to a ring chamber adjacent the valve, the valve having a collar which is movable in the ring chamber, the piston has a portion which depending on the position of the piston permits or prevents communication between the annular space and the third duct to obtain or not obtain pressurization of the ring chamber for s

Abstract: A reciprocating piston fluid powered motor having fluid inlet and outlet, wherein reciprocation is controlled by a reciprocable valve spool carrying a manifold communicating with said fluid inlet and outlet and cooperating with a valve slide shiftable on said valve spool to control reciprocation of said valve spool.

Abstract: An improved solenoid valve assembly for opening and closing a pressurized gas inlet for dispensing liquid from a dispensing apparatus comprises an enlarged relatively low pressure recess to which the solenoid plunger is exposed to automatically maintain the gas pressure inlet open until a full measure of liquid has been dispensed.

Abstract: A liquid pressure striking device defines a double-acting cylinder in a main body thereof having a tool at its lowest portion, and the double-acting cylinder houses therewithin a piston having an upper rod and a lower rod. The lower rod suspends a hammer for striking the tool, and the upper rod is provided on its outer circumference with a change-over valve mechanism which comprises a valve body of special structure for automatically switching the liquid flow under pressure by vertical movement of the piston, and a valve chamber having a plurality of concaves for controlling said valve body. Above the upper part of the valve chamber, there is provided an accumulator serving as a cap or cover of the main body. The main body is formed with an inlet passage of the liquid and an outlet passage, communicating with the accumulator and the valve chamber.

Abstract: Control apparatus includes means defining a housing having a hollow and a piston device mounted for reciprocating movement in said hollow under the influence of pressure fluid applied alternately to each of opposite portions of its surface, characterized by means for transmitting a signal of a predetermined travel of said piston in one direction, said signal transmitting means being constructed and arranged to utilize applied pressure fluid in its signalling function.

Abstract: A hammer or impactor apparatus including improved motive fluid means cooperable with spring bias means to reciprocably drive a hammer element and an improved process of hammer cycling achieved thereby.

Abstract: An actuator valve for an air driven reciprocating device wherein the valve includes a control rod responsive to movement of the reciprocating device and a valve piston pneumatically actuated by movement of the control rod. The valve piston selectively directs air to reciprocate the driven mechanism. The control rod includes dual axial passageways to selectively vent each end of the cylinder within which the valve piston operates. The passageways are sealed such that unused pressurized air will not escape from the air valve.

Abstract: Apparatus for converting energy contained within a stream of gaseous refrigerant to mechanical work. A refrigerant motor utilizing a diaphragm dividing a chamber into an equalizing chamber and a driving chamber is utilized with appropriate valve means causing the refrigerant to flow into and out of the driving chamber. A rod connected to the diaphragm reciprocates to deliver work to the appropriate work piece. Both rocker arm and spool valve embodiments are shown for providing the appropriate valve arrangements.

Abstract: A hand-operated pneumatic impact machine comprising a hollow body with an axially-reciprocating impact ram inside which forms, together with the body, variable-volume working chambers. It also comprises a distributing space communicating with the working chambers and with a source of compressed air. There also is a valve in the form of a cylindrical bushing whose inner surface covers at least one hole which admits compressed air into the distributing space, the compressed air forcing the valve to cover alternately the inlet channels of the working chambers for reciprocating the impact ram. The valve has at least one longitudinal channel which is in constant communication with the source of compressed air through a hole which connects the distributing space with the source of compressed air, the channel being intended to deliver compressed air to the inlet channels of the working chambers.

Abstract: A reversing control valve for a fluid operated downhole oil well pump having reciprocating pistons that is constructed to control the velocity and reversing of the pistons. The control valve functions to control the piston velocity and prevent damage to the pump components due to shock stresses induced by pressure impulses typically associated with pumped well fluids. The reversing control valve is constructed to regulate the piston velocity in response to the sensing of several pressure conditions in the well and in the pump.

Abstract: A cylinder control device of a hydraulic cylinder apparatus including a main directional control valve having a pilot chamber for controlling the reciprocatory movement of the piston, and a first valve including a plurality valve members for selectively communicating the pilot chamber, via an auxiliary directional control valve, to the fluid discharging tank side of the working fluid circuit when the piston reaches a predetermined position in its rearward stroke. The pilot chamber is brought into communication, via a passage, to the pump side of the working fluid circuit by a second valve when the piston reaches the end of its forward stroke. A control valve using the pump side pressure as a pilot pressure is mounted in the passage connecting the second valve to the pilot chamber or in the passage connecting the pilot chamber to the auxiliary directional control valve.

Abstract: An actuator valve for an air driven reciprocating device wherein the valve includes a control rod responsive to movement of the reciprocating device and a valve piston pneumatically actuated by movement of the control rod. The valve piston selectively directs air to reciprocate the driven mechanism. The control rod includes a single axial passageway to selectively vent each end of the cylinder within which the valve piston operates.

Abstract: A fluid arrangement for the alternating operation of an apparatus includes a working cylinder with a working piston endowed with an alternating movement and a control cylinder with an alternatingly moving control piston. Each of the cylinders has for the respective piston a driving chamber which is alternately connected to a supply source of fluid under pressure and to a discharge opening for the fluid through a distributor, and a return chamber permanently connected to the supply source of fluid under pressure. The distributor connected to the driving chamber in the working cylinder is the control cylinder, and the distributor connected to the driving chamber in the control cylinder is the working chamber.

Abstract: In thrust chambers of a recompressor piston are arranged ports which are joined to conduits leading to opposite fronts of the distributor piston of a five way valve. Flow passages lead to thrust chambers provided with conduits which, through a unidirectional valve, penetrate along the interior of a coaxial stem to the recompressor piston, and constitute fixed variators of the volume in the recompression chambers when the recompressor piston is cyclically displaced.

Abstract: A hydraulic percussion or an impact apparatus for driving rock-breaking tools, drill bits and ramming or tamping tools comprises a body in which an end of the tool is received and a reciprocating mass formed as a piston which is axially displaceable in a cylinder. The cylinder is provided with a distributor member slidable above the piston and of the same diameter as the latter, the distributor being formed as a sleeve having a central portion engaging a collar of a plunger which extends into a piston and forms therewith a suction chamber. The plunger has an extension which is slidable in a bore of the body and is acted upon by the high-pressure fluid.

Abstract: An impact tool is described which is capable of developing percussive forces for rock drilling, pile driving, seismic exploration and other repetitive high force applications. The tool contains a hammer and a valve which may be hydraulically actuated so as to oscillate; repetitively executing forward and return strokes during each cycle of oscillation. The valve is actuated in the forward stroke direction by being engaged by the hammer, and in the return stroke direction by fluid pressure means so as to switch the pressure in a cavity in which both the valve and the hammer are disposed for developing forces on the hammer so as to sustain its oscillation. A fluid filled pocket is provided into which the valve enters as it moves in the forward stroke direction, after having switched the pressure in the cavity. A passage is provided on the hammer which is dimensioned so that fluid in the cavity is either connected to a channel, the cavity, or entrapped in the pocket, depending on the position of the hammer.

Abstract: In a hydraulic striking device having a reciprocating piston there are first and second cylindrical spaces surrounding the piston, the first space continuously communicating with a high pressure circuit and the second space alternately communicating with the high pressure circuit and a low pressure circuit. A special sleeve-shaped control valve in the second space reciprocates axially of the piston to achieve the desired operation.

Abstract: An hydraulically operated striking apparatus for driving a rock drill or the like comprises a body having an axial, generally cylindrical, interior space with an inwardly protruding annular member. A cylindrical piston is positioned in the space in sliding contact with the protruding annular member, and the piston has canal means in its outer surface. The body, the annular member and the piston define two annular spaces and an annular distributing valve is slidably disposed within one of the spaces. The two spaces communicate with each other by means of the piston canal when the piston is in a first slidable position, and the protruding annular member prevents communication between the two spaces when the piston is in a second slidable position. The piston is provided with an axially disposed extension which, in combination with an outlet means, serves to permit a third, annular axial space to communicate with either an inlet means or an outlet means at all times.

Abstract: A hydraulically operated percussion apparatus comprising a housing in which a reciprocating impact piston is arranged to transfer impact energy to an impact tool, pressure chambers defined between said housing and said piston, and a channel system including a high pressure and a low pressure branch for conducting hydraulic pressure fluid to and from the pressure chambers, a first one of said chambers containing a movable distribution valve member responsive to the movements of the piston for alternately connecting said first chamber to said high pressure branch and said low pressure branch, respectively, characterized in that said valve member is arranged to be transported by the piston when moving in one direction, and responsive to the movement of the piston in the other direction to be acted upon by the pressure fluid to move in said other direction by means of hydrostatic pressure, said valve member having a longer path of movement than the impact piston and being arranged, at its movement in said one dir

Abstract: A hydraulically-operated reciprocatory device such as a road-breaking hammer includes piston means having an enlarged area portion which enters an overtravel-damping dashpot cavity. The dashpot cavity is in a chamber connected in series with valve means controlling the flow of hydraulic fluid such that said fluid flow through the chamber removes heat generated during a damping action.

Abstract: An impact motor has a reciprocating piston that has its piston rod guided in bushings in the housing. The bushings are lubricated by oil-loaded compressed air but the piston is forced to reciprocate by oil-free compressed air.