Abstract: Methods, apparatus, systems and articles of manufacture are disclosed that produce a pneumatic actuator end cap having an integral volume booster. An example pneumatic actuator end cap includes a first cavity to provide a first fluid passageway to receive a pressurized fluid from a source external to the pneumatic actuator end cap, a second cavity to provide a second fluid passageway to route the pressurized fluid to an internal chamber of a pneumatic actuator in which a piston is disposed, and a third cavity containing a fluid valve to control a flow of the pressurized fluid between the first fluid passageway and the second fluid passageway.

Abstract: A hydraulic hammer is provided. The hydraulic hammer includes a fluid inlet configured to receive a pressurized fluid for running the hydraulic hammer and a fluid outlet for discharging hydraulic fluid from the hydraulic hammer. A bypass passage fluidly connects the fluid inlet and the fluid outlet, the bypass passage has a bypass inlet fluidly connected to the fluid inlet and a bypass outlet fluidly connected to the fluid outlet. An automatic shut-off valve is disposed in the bypass passage between the bypass inlet and the bypass outlet and is configured to open or close the bypass passage. The automatic shut-off valve is configured to open the bypass passage under pressure of the pressurized fluid on continuous running of the hydraulic hammer for a set time to stop the hammer.

Abstract: A rotary actuator includes a first housing defining a first arcuate chamber having a first cavity, a first fluid port in fluid communication with the first cavity, and an open end. A rotor assembly is rotatably journaled in the first housing and having a rotary output shaft and a first rotor arm extending radially outward from the rotary output shaft. An arcuate-shaped first piston is disposed in the first housing for reciprocal movement in the first arcuate chamber through the open end, wherein a first seal, the first cavity, and the first piston define a first pressure chamber, and a first portion of the first piston contacts the first rotor arm.

Abstract: A pneumatic control device includes a base comprising a reservoir, a first check valve for only allowing hydraulic fluid to flow into the reservoir, and a second check valve for only allowing the fluid to flow out of the reservoir; a hollow cylinder comprising a spring biased piston; a body mounted to the cylinder thereunder and releasably secured to the base, the body comprising a stepped-diameter passageway with a poppet mounted therein; and a cover releasably secured onto the poppet. In response to feeding pressurized air into the cylinder, the fluid in the reservoir flows out during a first stroke of the piston, and the fluid is sucked back into the reservoir during an opposite second stroke of the piston. In one embodiment, the fluid is for actuating a machine vise.

Abstract: The invention concerns an apparatus comprising a body (1) containing a cylinder wherein is mounted sliding an impact piston (1) of a tool, the motion of the piston being controlled by a distributor (15) which, arranged coaxial to the impact piston, is mounted inside a distribution box (3). The distribution box (3) comprises a part axially overlapping the piston (1) and arranged concentric thereto, and the distribution box (3) defines with the piston a control chamber (13) which, successively put under the high (9) and the low (12) pressure of the fluid, communicates through a passage (16) arranged in the distribution box (3) with a chamber controlling (14) the movement of the distributor (15), to generate alternately low pressure and high pressure.

Abstract: A hydraulic pump is equipped with an air motor, which is disposed in a housing and oil reservoir of the hydraulic pump, connected to an air source, and has a piston movable in a tube so that pressured air from the air source can cause reciprocation the a piston to pump hydraulic oil to other equipments such as a jack. The air actuated hydraulic pump is equipped with a pilot operated guided poppet valve comprised of several parts in separable connection, and a muffler so that the user doesn't have to replace the whole piston with a new one if only one of the parts is damaged, and that noise can be reduced when the pump is working.

Abstract: A vibration generating apparatus comprises a cylinder assembly (6) having a cylinder and a piston (3) slidably inserted in a cylindrical bore (2) of the cylinder for defining a first pressure receiving chamber (4) with a small pressure receiving area and a second pressure receiving chamber (5) with a large pressure receiving area. The piston (5) is selectively movable in one direction and in the other direction responsive to pressures in the pressure receiving chambers. A switching valve (9) has a first pressure chamber (13) with a large diameter, a second pressure chamber (14) with a small diameter, a pump port (10), an auxiliary port (23), a principal port (11) and a tank port (12). The switching valve (9) takes a first position under a pressure within the first pressure chamber and takes a second position under a pressure within the second pressure chamber.

Abstract: The impact hammer comprises a working piston (22) exerting impacts onto an impact surface (23). The hydraulically driven working piston (22) is reciprocatingly controlled by a control means (40,41). At the rearward end of the working cylinder (21), there is a rear chamber (50) into which the projection of the piston (51) immerses. Connected to the rear chamber (50) is a pressure gas reservoir (52) which is charged with each return stroke of the working piston and discharges with the subsequent working stroke.

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: Apparatus comprising a striking piston driven hydraulically in a reciprocating fashion by an incompressible fluid inside a cylinder and striking against a tool, of the type in which the piston slides in a cylinder having two concentric piston bearing surfaces of different sections, of which that situated on the tool side has a section smaller than that remote from the tool, the piston and the cylinder delimiting two antagonistic chambers, an annular bottom chamber and a top chamber of larger section.According to the invention the interior of the top chamber is permanently at a regulated pressure of a value intermediate between the inlet or high pressure and the outlet or low pressure, and the annular bottom chamber is connected alternately by a distributor to the high pressure supply circuit during the upward phase of the piston and to the top chamber during the accelerated downward phase of the piston.

Abstract: A reciprocating pneumatic motor for hydraulics has a pair of guide grooves on the inner wall of a cylinder provided, together with a pneumatic piston and a shuttle valve to function pneumatically. The piston has a seal ring which passes the guide grooves to allow air to flow into the shuttle compression chamber, pushing the shuttle valve and opening up a channel for the venting of air. This continuous air flow and venting causes the piston to reciprocate. In addition, the piston is integrated with a ring plate using plastic ultrasound technology which simplifies the structure of the pneumatic motor.

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: 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: In the hydraulic breaker according to the present invention, oil pressure at a fixed value always flows in the circuit at a low pressure side whenever the piston is raised or lowered, to prevent the need for an accumulator in the circuit at the low pressure side. At the same time, a high pressure oil is required during the raising and lowering of the piston, bringing about less of a change in the surge pressure, attributing to the fact that there is no need for an accumulator in the circuit at the high pressure side. Moreover, the hydraulic breaker of the present invention is advantageous by providing an increased striking force because the high pressure oil is used, in addition to the reaction force of the compressed nitrogen gas, when the piston is lowered to strike the chisel.

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: In the hydraulic breaker according to the present invention, oil pressure at a fixed value always flows in the circuit at a low pressure side whenever the piston is raised or lowered, to prevent the need for an accumulator in the circuit at the low pressure side. At the same time, a high pressure oil is required during the raising and lowering of the piston, bringing about less of a change in the surge pressure, attributing to the fact that there is no need for an accumulator in the circuit at the high pressure side. Moreover, the hydraulic breaker of the present invention is advantageous by providing an increased striking force because the high pressure oil is used, in addition to the reaction force of the compressed nitrogen gas, when the piston is lowered to strike the chisel.

Abstract: An impact device that consists of a housing having a bore, a piston, and a change-over valve for control of the reciprocal movement of the piston is presented in the present invention. In the present invention, it is not necessary to employ a long-size piston and a high piston speed is obtained and, further, a compact device in which the fluctruation of the pressure in the low pressure path is small can be obtained.

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: The hydraulic circuit of the present invention allows flotation of the header without extensive use of accumulators and is readily adaptable to present open center hydraulic systems. The present invention is also adaptable to closed center hydraulic systems with or without flow compensation. The hydraulic system has a pump selectively connected with the header cylinder. Pressure within the header cylinders is automatically maintained at a constant level by fluid addition to the cylinder or by extracting fluid from the cylinders.

Abstract: An all-hydraulic impactor for percussion tools and the like embodying an oil accumulator and an annular sleeve valve. Hydraulic fluid is initially supplied to the accumulator at full supply pressure and is then charged, for example, to three times the supply pressure by a differential piston arrangement. The impactor of the invention minimizes the required volume of the accumulator.

Abstract: An oscillator actuated hydraulic impulse of the type including a spool valve actuated by an alternating signal from an oscillator to switch the hydraulic pressure in a double acting cylinder in order to cause reciprocating motion of a piston which strikes a boring tool. The hydraulic impulse device further includes a means for controlling the transition from the impulse stroke to the return stroke of the piston. In some embodiments, the hydraulic impulse device may further include a means for varying the duration of the impulse stroke and the return stroke of the piston.

Abstract: A two-stage pump is illustrated of the type employing a piston having two diameters, one capable of providing a large volume of fluid flow at low pressure so as to move a fluid operated press rapidly until a load is encountered, at which time fluid is delivered at a low volume at high pressure for operation of the press wherein the flow control means are positioned in a piston housing independent of the piston.

Abstract: Reciprocating drive means powered by a fluid such as compressed air comprising an elongate inner member with a plurality of passageways therein, an outer member slidable on the inner member and a shuttle member slidable with respect to the inner member and within the outer member, the passageways in the inner member being variously and intermittently so connected in use to each other by way of ports in the inner member and compartments provided within the outer member and the shuttle that, upon connection of a determined one of said passageways to a fluid pressure source the outer member moves with reciprocating action with respect to the inner member.

Abstract: A reciprocating piston fluid powered motor providing great flexibility in its mounting and the location of the motor shaft and fluid inlet lines. Relatively few component parts are employed and a number of the components are used as-cast or with minimal machining operations required.

Abstract: A hydraulic apparatus for generating impacts comprising primary members having striking and control apparatus which is made up of a plunger which moves reciprocatingly, for striking a tool, inside a housing having an intermediate working zone which has a single inner diameter. An intermediate part making up a piston of the plunger fits therein and has a corresponding single diameter. There is no flow of fluid between these two members and the movement of the plunger is controlled by secondary members and tertiary members which are located in respective housings which make up several chambers, and in which the corresponding plungers are reciprocatingly movable. The apparatus further includes means for discharging the fluid under pressure from within the apparatus for stopping its operation when the tool is not at rest on a workpiece so that the main plunger descends inside the housing to a point below its normal lower operating position.

Abstract: A compressed-air operated dispenser for continuously dispensing a substance enclosed in a container, and in particular a viscous or paste-like substance, comprising an outlet passage extending from container to an outlet; a valve which normally closes the passage; a compressed-air operated piston arranged to exert pressure on a substance in the passage and to open the valve; and a trigger means for initiating the supply of compressed air for the purpose of operating said piston.In accordance with the invention there is provided a second valve arranged to move the piston to a starting position in which a pressure-actuating chamber is closed on one side of the piston with the exception of a passage through which compressed air can be forced into the chamber to cause the piston to move to a first terminal position. In this position the substance is subjected to pressure and the valve is opened and the piston ceases to act on the second valve.

Abstract: A reciprocating piston motor has the piston biased in return stroke direction and driven in power stroke by air pressure introduced between the head of the piston and a closure across the end of the working chamber cylinder. A valve which closes an exhaust port leading from the working chamber, is opened at the end of the power stroke by working chamber air pressure and the air pressure is evacuated from the working chamber. The valve is returned to closing relation to the port by the returning piston, thereby resetting the motor for another cycle of operation.

Abstract: A fluid pressure control circuit for periodic operation of fluid pressure operable drives or motors of the type such as used for windshield-wipers as well as for fluid pressure operable pulsating drives having a double-acting operating cylinder and wiper motor, and an associated control piston.

Abstract: A hydraulically driven hammer is disclosed, along with valve actuation arrangements which operate to switch hydraulic forces on the hammer ram after preselected intervals following application of pressurized pilot fluid flows. These flows pass into a fluid accumulation chamber unitl a predetermined volume is accumulated after which continued pilot fluid flow produces valve actuation.

Abstract: A fluid operated hydraulic pump of the type using air pressure to produce high pressure hydraulic fluid wherein an air pressure driven motor and a hydraulic pump are positioned in adjacent axially aligned relationship and the air motor drives the hydraulic pump, the air motor including a reciprocable check valve for preventing air flow into the pump during the exhaust stroke of the pump thereby increasing the efficiency of the pump and reducing air flow through the pump. The check valve is disposed in the air inlet passage and is positioned in axially aligned relationship and adjacent to a reciprocable shuttle valve controlling exhaust air flow from the motor. Movement of the shuttle valve to a position permitting air to be exhausted from the air motor chamber also facilitates movement of the reciprocable check valve to a position wherein it prevents air flow into the motor.

Abstract: A hydraulically driven hammer is disclosed, along with valve actuation arrangements which operate to switch hydraulic forces on the hammer ram after preselected intervals following application of pressurized pilot fluid flows. These flows pass into a fluid accumulation chamber until a predetermined volume is accumulated after which continued pilot fluid flow produces valve actuation.

Abstract: A percussion tool is hydraulically operated by a piston whose stroke is controlled by a spring biased valve. A pressure accumulator is connected to the working pressure chamber of a hydraulic cylinder and receives pressure therefrom during the return stroke of the piston while discharging pressure during the working stroke. A piston is displaceably mounted in the pressure accumulator for movement into an end position when the pressure is discharged and a second valve is actuated by the piston in the end position to control the spring biased valve.The invention refers to an improvement in hydraulic percussion tools.Hydraulic percussion tools, for rock drilling, breaking or the like of known construction have a reciprocating working piston in a cylinder, driven by a pressure liquid, usually hydraulic oil, during the reciprocating movement.