Abstract: An active chamber engine, includes at least one piston (2) slidingly mounted in a cylinder (1) and operating according to a three-phase thermodynamic cycle including an isobaric and isothermal transfer, a polytropic expansion with work and an exhaust at ambient pressure, which is preferably supplied with compressed air contained in a high-pressure storage tank (12), in which the volume of the cylinder (1) swept by the piston is divided into an active chamber (CA) and an expansion chamber (CD), and in which the compressed air is used to move the intake valve (9) in order to open and then close the intake duct, making it possible to supply the active chamber of the engine, the compressed air having been used for the actions then being reused in the engine to produce additional work.

Abstract: An expansible chamber pneumatic system, for example a fluid pump system, includes two or more double-acting diaphragm pumps, each with symmetrical left and right pump housings, each housing including an air chamber and a fluid chamber separated by a movable diaphragm. The diaphragms are connected for reciprocating movement in unison to pump fluid through their respective fluid chambers. Each pump includes an air valve actuated by Control air to direct Process air into one of the air chambers, simultaneously releasing used Process air from the other air chamber to thereby move the diaphragms, thereby to pump fluid. A pilot valve directs Control air to the air valve to position the air valve. The pilot valve is responsive to diaphragms reaching their travel limit in one direction to direct Control air to reverse the directions of Process air flow through the air valve to thereby reverse the movement of the pump diaphragms. Control air exhausts through the pilot valve to atmosphere.

Abstract: A pneumatic fixing machine has a piston (30) sliding within a cylinder (33), a first valve (5) movable between opening (L) and closing (D) positions, in correspondence of which the first valve connects an inlet portion (33a) of the cylinder (33) with either a feed of pressurized fluid or with an external outlet, respectively. A second valve (2) is operated by a trigger (7), the second valve being movable between an occlusion position (M) and a passage position (L) to either connect a first duct (9) and a base portion (5a) of the first valve (5) with the feed of pressurized fluid or with an external outlet.

Abstract: Fluid pump assembly driven by a reciprocating piston, having an improved coupling between a driving shaft and a driven shaft and a fast-shifting switching mechanism for changing the direction of movement to the piston.

Abstract: New tungsten carbides alloyed with fluorine in amounts up to 0.5 wt % and possibly with fluorocarbon compositions are described. It is possible to produce them by means of a new process of chemical vapor deposition, in which tungsten hexafluoride, hydrogen and a carbon-containing gas are used. A specific feature of the new process is the preliminary thermal activation of the carbon-containing gas. The tungsten carbide coatings are deposited on construction materials and items made from them. They possess enhanced resistance to wear, corrosion and chemicals.

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: 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. Enlarged 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. The actuator housing is molded about the center bushing for the control shaft and includes inwardly extending portions. Annular passages are then machined in the bushing for sealing channels to receive O-rings. The O-rings extend to seal against the housing directly at the floor of the sealing channels.

Abstract: In the preferred and illustrated embodiment of a reciprocating pump, a plunger for pumping a liquid, a piston for reciprocating the plunger and a selector valve for changing a pilot flow passage between a supply passage communicating a pressure chamber with a supply port and a discharge passage communicating the pressure chamber with a discharge port are disclosed. The selector valve is switched by a pilot valve means. A pilot valve body of the pilot valve means is so designed to engage with the piston for predetermined distances to and from the ends of the respective forward and backward strokes of the piston and to be moved to the switching position where the pilot valve body opens one of the pilot supply passage working against the selector valve and the pilot discharge passage and close the other of the pilot passages and the pilot valve body is released from engagement with the piston and held at the switching position for a predetermined distance after the stroke of the piston is reversed.

Abstract: A compressor (2) uses lower pressure compressed air from a compressed air supply (4, 6) to automatically create higher pressure compressed air. This compressor includes a pressure intensifier (8) having a piston assembly (16) sized for reciprocal movement between forward and retracted positions. The first cylinder (20) has an inlet (10) coupled to the air supply. The second cylinder (22) has an outlet (14) and a supplemental inlet (38). A first check valve (40) couples the supplemental inlet to the ambient atmosphere to permit fluid to flow through the first check valve and into the second cylinder through the supplemental inlet, but not the reverse. A second check valve (42) is coupled to the outlet and permits fluid to flow from the second cylinder, through the outlet and through the second check valve. The compressor also includes means for venting (48) the first cylinder to atmosphere when the piston assembly is in the forward position to permit the piston assembly to return to the retracted position.

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: An apparatus for driving a piston by fluid pressure in which a piston (8) is reciprocated upward and downward by supplying and discharging pressure fluid to and from an actuation chamber (9) disposed in a cylinder (7) through a pilot valve (18) and a fluid pressure supply-discharge valve (13). Above a supply-discharge valve member (30) of the supply-discharge valve (13) there is provided a cylinder chamber (70a), into which a pilot valve casing (71) is inserted so as to hermetically slide up and down. The fluid pressure in the discharge actuation chamber (35) disposed above the supply-discharge valve member (30) allows the pilot valve casing (71) to ascend against a return spring (73).

Abstract: A fluid operable engine has a cylinder in which a piston slides up and down. The cylinder has a cylindrical wall and two end walls. The piston divides the cylinder into two chambers. The piston is hollow, has a cylindrical wall and two end walls, with a rigid tube extending from and through one end wall of the piston through an adjacent end wall of the cylinder so that the interior of the piston communicates with the exterior through the tube. The cylinder has an aperture in each end wall or in its cylindrical wall close to the end walls and the piston has an opening in each of its end walls. A closure member is provided for alternately closing the openings or the apertures as the piston reaches each end wall. The engine is operated either in a positive or negative manner, with fluid being charged into or sucked from the piston or the cylinder. The openings may be closed from within or without and the apertures may be closed from inside or outside. The closure member may be mechanically or fluid operable.

Abstract: Control valve means for a driving tool operated with compressed air for the driving of fasteners into workpieces. Through a specific design of the main and the auxiliary valve and through a connection to the piston return chamber the control of the valves are brought into synchronization with the movement of the working piston. By this, high repetition frequencies can be achieved. Further, in the mode "automatic operation" also single shot operation is possible.

Abstract: A hydraulic percussion device comprises a housing defining a longitudinal cylinder, a piston longitudinally reciprocal in the cylinder and subdividing same into a front compartment and a rear compartment, and a tool engageable longitudinally with the piston at the front compartment. The compartments are alternately and oppositely hydraulically pressurized to move the piston forward to strike the tool while traveling at an end speed and to move the piston backward away from the tool, the rate of alternation being a frequency parameter and the speed being a force parameter. A controller varies at least one of the parameters by detecting how much the piston rebounds from the tool after striking same and operating the control means in accordance with how much rebound is detected. How much the piston rebounds can be detected by sensing the pressure in one of the compartments immediately after the piston strikes the tool.

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: An air driven diaphragm pump having an actuator valve for converting a source of compressed air into a reciprocating drive. The actuator valve includes a valve piston for alternately directing air to one side or the other of the pumps, a control rod fixed to the reciprocating elements of the pump and means for shifting the valve piston responsive to the position of the control rod. An axially spaced bifurcated inlet is employed to provide additional energy to the shifting of the valve piston. The valve piston also is arranged to cover vent ports as a mechanism for closing off all compressed air under stalled conditions of the pump.

Abstract: The invention concerns an extrusion device for impregnating rock formations preferably for bonding with a liquid synthetic product, with the use of a piston pump having at least one working cylinder. During the induction or suction stroke a working piston is filled with the extrusion liquid or with one of its components, and is emptied during the delivery stroke cycle. The working piston is controlled by a pump drive equipped with at least one driving cylinder and a driving piston which can be pressurized on both sides of the piston sequentially. A control valve pressurizes the piston surface with a working fluid as the other working surface of the piston is relieved. The extrusion device, can operate with more efficient utilization of the energy source applied and in particular with extremely high operating pressure of the available hydraulic medium, which is already available but used for other purposes, i.e., the operation of the rams or the hydraulic face- and/or roadway supports.

Abstract: The hydraulic operated surface pumping unit of this invention is a counterbalanced cross beam type pumping unit driven by a hydraulic cylinder. The pumping unit can be operated in a first mode of equal upstroke and down stroke speeds or in a second mode of slower upstroke and faster down stroke speeds. The stroke lengths are controlled by cams and are adjustable over a large range. Stroke cycle speeds can be varied by adjusting the output rate of a hydraulic pump used to drive the system. The main hydraulic valve includes intermediate lock positions to hold the pumping unit steady during phase shifts between upstrokes and down strokes and during shut down of the pumping unit. Pressure indicators are provided for optimum counterbalancing of the pumping unit, and a needle valve control for return fluid flow to tank is provided for slow let down of the pump rod for initial tag out settings.

Abstract: A reciprocable drive mechanism has a fluid pressure operable ram controlled by a spool valve, a two-position valve and a braking valve. During a powered stroke of the ram, the spool valve closes an exhaust path of the two-position valve so that the latter remains in a first position in which pressure fluid is obliged to flow through the braking valve, in a fully opened condition, to the cylinder of the ram. At the end of the powered stroke the spool valve is shifted to a second position in which it permits exhausting of fluid through the two-position valve, and as a result of change of differential pressure in the latter, the pressure fluid previously obliged to flow through the braking valve is permitted to flow to exhaust. The braking valve is then less open, so the ram carries out its return stroke at a slower rate.

Abstract: A pneumatic pump includes a pneumatic cycling mechanism that permits the commencement of each successive pumping interval only upon the appearance of a pilot signal. The pilot signal is generated by a pneumatically operated pump timer that determines the pumping interval. The pilot signal is terminated during the pumping interval after a signal timer has timed out. The pump, timers and other pneumatic circuit elements are driven by the same source that powers the pump, and no reference to an externally generated timing signal is required.

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: 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: An air motor comprising a cylinder, a piston, and a valve mechanism for controlling the supply and exhaust of air to and from opposite ends of the cylinder, the valve mechanism comprising a D-valve and an actuator for the D-valve operable by the pressure air for driving the piston, movement of the actuator being controlled by valves at opposite ends of the cylinder for exhausting air from opposite ends of the actuator, these exhaust valves being operated by the piston, and the motor having means operable by the piston at each end of its stroke for restricting the exit of air from the cylinder to cushion the piston and prevent it from striking the ends of the cylinder.

Abstract: A hydraulic hammer wherein the reciprocal motion of a drill-striking piston is operated by means of a spool valve for switching hydraulic pressure to a double-acting cylinder depending upon the position of the piston. The hydraulic hammer further includes a self starter means which assures activation of the hammer whenever hydraulic pressure is applied to the hydraulic hammer and a means for compensating for variations in boring conditions such that energy is efficiently delivered by the drill striking piston.

Abstract: A reciprocating, fluid operated pump, which is reversed at opposite ends of its travel by shifting of a directional valve, is characterized by a control valve for rapidly and completely shifting the directional valve.In the disclosed embodiment, the pump includes a pair of pumping portions each operated by a respective reciprocating air motor. The air motors are coupled for conjoint reciprocation, and the directional valve alternately applies compressed air to one and then to the other of the air motors. The arrangement is such that when air is applied to one of the motors fluid is forced from its associated pumping portion to an outlet from the pump while fluid is drawn into the other pumping portion from an inlet to the pump, and when air is applied to the other of the motors fluid is forced from its associated pumping portion to the outlet from the pump while fluid is drawn from the pump inlet into the one pumping portion.

Abstract: A fluid-actuated, such as a pneumatically actuated, hydraulic pump of either the single acting or the double acting type is controlled in its operation by a main valve member which has two connecting compartments the fluid in one of which is always at the atmospheric, and in the other always at a superatmospheric, pressure. The main valve member has two end faces, one larger than the other, the smaller being always acted upon by the superatmospheric pressure of the fluid and the larger one intermittently. An auxiliary valve member controls the admission of the pressurized fluid to the larger end face and is open only during the reversal of the hydraulic pump from suction to pumping stroke, while the pressure acting on the larger end face is relieved during reversal from the pumping to the suction stroke. A duct communicates one or the other of the connecting compartments of the main valve member which an actuating compartment of an actuating unit, depending on the position of the main valve member.

Abstract: A control valve for alternately applying fluid pressure to two drive members of a reciprocating work device such as a pump. A valve piston is slideable in a closed cylinder to which pressurized fluid is transmitted. The valve piston, controls the fluid depending on the position of the piston in its cylinder, to pressurize one chamber and vent the other so as to move the work device in one direction or the other. In turn, the work device controls the fluid to position the valve piston.

Abstract: The device is an air driven piston in a cylinder driving a pump. A shuttle valve is provided to control the admission of air under pressure to, and exhaust from the cylinder. The shuttle valve is a double ended piston operating in coaxial bores with a stem part of smaller diameter between the ends. The air passes to the cylinder through the bore around the intermediate part of the double ended shuttle valve. The piston at one end of the shuttle valve has greater area exposed to pressure than the area of the piston on the other end of the valve. The shuttle valve is operated by one or more pilot valves that are actuated by the main piston. The shuttle valve is shifted by controlling the pressures acting on the parts of the pistons having exposed areas of different sizes.

Abstract: A fluid operable engine has a cylinder in which a piston slides up and down. The cylinder has a cylinder wall and two end walls. The piston divides the cylinder into two chambers. The piston is hollow, has a cylindrical wall and two end walls, with a rigid tube extending from and through one end wall of the piston through an adjacent end wall of the cylinder so that the interior of the piston communicates with the exterior through the tube. The cylinder has an aperture in each end wall or in its cylindrical wall close to the end walls and the piston has an opening in each of its end walls. A closure member is provided for alternately closing the openings or the apertures as the piston reaches each end wall. The engine is operated either in a positive or negative manner, with fluid being charged into or sucked from the piston or the cylinder. The openings may be closed from within or without and the apertures may be closed from inside or outside. The closure member may be mechanically or fluid operable.