Abstract: In a hydraulic drive of a tool piston in a cylinder first and second flat contact areas each are contiguous, when moving into and in the open position of the valve member between the detent element and the valve member, wherein a pressure-limiting valve that can be loaded with the pressure in the cylinder from a closed position to an open position and a detent element loaded by a spring in the locking direction to positively hold a neck of a valve member of the pressure-limiting valve are arranged in the open position, wherein the detent element at least via the tool piston at its return to a released position can be moved and, when moving the valve member to the open position of the pressure-limiting valve, non-positively acts on the valve member.

Abstract: An Example can include an elongate pump barrel extending along a length and defining an elongate hollow piston chamber. The Example can include a piston slidably movable within the piston chamber to compress air within the piston chamber. The Example can include a piston rod connected to the piston. The Example can include a handle connected to the piston rod to reciprocally slide the piston in the piston chamber. The Example can include a piston rod seal disposed around the piston rod and coupled with the elongate pump barrel. The Example can include a downward opening air intake passage, located away from the rod seal, in fluid communication with a top of the piston.

Abstract: In a liquid supply apparatus, plungers which respectively expand and contract pump chambers are reciprocated linearly in an axial direction with their phases shifted to each other, thereby continuously discharging liquid. In a pump block, drive rods are mounted so as to be reciprocatable in an axial direction. At a center in an axial direction of shafts attached to the drive rods, drive rollers are mounted, and rollers are mounted at both ends of the shafts. Guide grooves which support the guide rollers are formed in guide blocks.

Abstract: A compression apparatus for compressing a fluid, the apparatus having a frame and a motor mounted to the frame, the improvement comprising a drive mechanism installed on the frame so as to be driven by the motor and at least one piston-cylinder unit operably connected to the drive mechanism, the piston-cylinder unit having a cylinder, a piston slidably installed within the cylinder, and a piston rod interconnecting the piston and the drive mechanism so as to shift the piston up and down within the cylinder.

Abstract: The present invention provides a piston pump for liquid in which a sump is defined in a chamber into which sump liquid in the chamber flows due to gravity. A passageway leads from an outlet of the sump out of the chamber to a dispensing outlet. The dispensing outlet is at a height below the height of the sump outlet and fluid to exit the sump flows from the sump outlet upwardly in a first portion of the passageway to a height above the sump outlet then downwardly to the dispensing outlet. The chamber and its sump is defined between a piston chamber-forming member defining the chamber to be downwardly opening and a piston forming element axially slidable in the chamber.

Abstract: A supercharged internal combustion engine including a pressurized fluid outlet, the engine comprising a two-ended piston, with one end received in a combustion chamber, and another end received in a hydraulic chamber. The piston further including a portion intermediate the two ends and received within an air chamber, and the air chamber has an air outlet communicating with a combustion air inlet to the combustion chamber.

Abstract: A linear compressor for multi-compression includes a stationary cylinder, a moving piston, and a stationary piston. The stationary cylinder has a first compression chamber formed therein. The stationary cylinder is provided at one side thereof with an outlet part. The moving piston is movable forward and backward by a linear motor, that compresses a fluid in the first compression chamber. The moving piston has a second compression chamber formed and is provided, at the position where the second compression chamber communicates with the first compression chamber, with a first valve. The stationary piston is fixedly disposed in the compressor. The stationary piston is fitted in the moving piston so that the fluid in the second compression chamber is compressed as the moving piston is reciprocated.

Abstract: The purpose of the present invention is to provide a multi-cylinder compressor permitting to increase a gas inflow into the housing without enlarging the intake ports of the bearing plate. The bearing plate 12 bearing the crankshaft 9 is provided with plural intake ports 12a at regular intervals in the circumferential direction. The substantially inversely-dished cover member 14 is mounted on the top of the bearing plate 12, and it not only covers the plural intake ports 12a, but also forms a sealed space S between the cover member and the bearing plate 12, and is further provided with an introducing opening 14a larger than the intake port 12a at the center top of the cover member 14. The introducing opening 14a is fitted with the gas supply pipe 15 to be connected to the gas supply source (not illustrated).

Abstract: The invention relates to a piston pump (1) for delivering a fluid at low pressure and at a higher pressure, a higher delivery volume being provided in one pumping cycle at low pressure than at a higher pressure, having a low-pressure delivery piston (4), which is moved inside a pump cylinder (2) and acts upon a pressure chamber (7) under prestress into its delivery end position, a high-pressure delivery piston (11), an inlet valve (9) and an outlet valve (9, 10), a fluid delivery path (5) furthermore being provided between the inlet valve (9) and the outlet valve (10), and the low-pressure delivery piston (4) being able to be moved back counter to its prestress into a delivery starting position, and proposes, to achieve effective delivery at low pressure and at a higher pressure with the simplest possible construction, that the fluid delivery path (5) passes through the low-pressure delivery piston (4), that a valve (6) is provided in the low-pressure delivery piston (4), which valve shuts in the case of move

Abstract: A hand air pump includes a cylinder having a relatively small chamber and a relatively large chamber defined therein. A relatively small piston is slidably received in the relatively small chamber, and a relatively large piston is slidably received in the relatively large chamber. The two pistons are connected to an operative handle outside the cylinder. Air inside the relatively large chamber is accumulated in the relatively small chamber and is then outputted by the relatively small piston.

Abstract: A compressor which provides for minimum clearance in the compression chamber while substantially reducing the heat normally experienced by the piston during the compression stroke of a compressor of this type. The suction valve(s) of the compressor is concentrically mounted in the piston while the discharge valve(s) is concentrically mounted in a stationary position within the cylinder. Since the high heat of compression occurs at the discharge valve, the piston will be much cooler than in prior art compressors of this type which improves the efficiency of the compressor and which substantially extends the operational life of the piston rings.

Abstract: A reciprocable liquid pump having a priming cylinder affixed beneath the lower valve housing, and a priming piston rod affixed to the lower end of the pump piston valve assembly. A priming piston and priming valve are affixed to the lower end of the priming piston rod, the priming piston being slidable over a limited range of movement along the priming piston rod and having a central opening with a beveled valve seat. The priming valve forms a conical valve surface which is engageable against the priming piston valve seat to provide a controllable flow path through the center opening of the priming piston.

Abstract: There is presented a gas compressor including a housing defining adjacent first and second chambers in axial alignment, a rod extending through the first chamber and into the second chamber, a tubular projection extending from a first end of the housing into the second chamber, a cylindrically-shaped end portion fixed to the rod and disposed slidably upon the projection and within the second chamber, a piston fixed to the rod and slidably disposed within the first chamber, and conduits for admitting gas to the first chamber, transferring gas from one compression stage to another, and discharging compressed gas from the housing.

Abstract: A booster pump for a reverse osmosis water purification system. The booster pump has a spring return piston that is stroked by the pressure of feedwater. The pump also has a pair of solenoid control valves that control the flow of feedwater into and out of the pump to move the piston between stroke and return positions. The control valves are switched by a detector switch which detects when the piston reaches the fully stroked and return positions.

Abstract: A manually operated pump includes a pulley sheave oppositely wound with cord and rotatably mounted on a support element, a two-stage pump, and a reciprocal action shaft. The shaft is mounted eccentrically through the assembled pump, including through a clearance hole and slot in a main piston of the pump. The pump is a cylinder with a double-ended piston slidably mounted within and forming a main chamber at each end of the cylinder. An offset high pressure piston extends into the main chamber from each cylinder end for operation with offset high pressure chambers defined in each end of the double-ended piston. Passageways with differential air pressure valves lead from the slot to the main chambers, from the main chambers to the high pressure chambers, and from the high pressure piston to outlets.

Abstract: A two-stage piston pump has serially arranged pump chambers each having an input passage and a delivery passage. The first stage has a larger displacement than the second stage such that complete filling of the second stage is attained. The piston of the first stage is reciprocated through the cooperation of a spring and a selectively energizable solenoid coil. The piston of the second stage is secured to and reciprocable with the first stage piston. The cylinder for the second stage has an overflow passage disposed to ensure that all the fluid discharged from the first stage prior to the second stage piston closing the overflow passage passes through the second stage cylinder.

Abstract: A multi-stage pumping assembly comprising a plurality of pumping units arranged end to end in an elongate cylindrical housing. Each pumping unit comprises a solenoid which when energized causes a pumping piston to retract downwardly on its intake stroke, and when de-energized permits a tension loaded rubber sleeve element to pull the piston upwardly on its discharge stroke. Each of the solenoids is energized in sequence so that the pumping pistons move through their pumping cycles in a sequential pattern. In pumping against lower pressures, each piston is able to move through a longer path of travel on its discharge stroke to effect a higher volumetric flow of liquid. When working against higher head pressures, the pressure exerted by the several pumping pistons, working cumulatively effects a lower volumetric flow of fluid at a higher pressure.

Abstract: A cylinder houses a slidable piston that is separated into two axially spaced portions. A rod interconnects the portions and permits lost motion between the portions when the piston is slid in either direction in the cylinder. By valving and conduits, the piston and cylinder draw quanta of air and liquid mix, for ice milk or the like, together in selected proportion, mix these together and forward them from the pump, e.g. to a freezing chamber. Means are provided, for instance the rod may be exchanged for one of another size, for varying said selected proportion. Preferably a sensor is provided to cause the pump to operate intermittently, e.g. to replenish mix which has been withdrawn from the freezing chamber. Also by preference the freezing chamber is maintained at 10-40 p.s.i.g. in order to tend to prevent reduction of overrun between the time when the air is mixed with the liquid mix and the time when the frozen confection is dispensed.