Abstract: Power take off devices 10, 110, 210, 310 and 410 are disclosed. Each of the power take off devices include an integral planetary gear set coaxially arranged with the respective input shafts and output shafts of the devices to provide space efficient rotational torque at a large variety of large and small input to output ratios to a variety of accessory devices. The power take off devices 10 and 110 are two speed devices, and the power take off devices 210, 310 and 410 are single speed devices. In one embodiment, a power take off device 10 is mounted on and driven by a transmission of an over the highway truck to power a high speed blower mounted on the truck. The device 10 includes an input shaft 36 that meshes with and is driven by a gear in the transmission and an output shaft 37 that drives the blower. The shafts 36 and 37 are mechanically connected through a planetary gear set 52.

Abstract: A hydraulic actuator apparatus includes a hydraulic cylinder having a top and bottom face wherein a rotatable piston is movably disposed. Top and bottom pistons rods that are rotatably removable and couple to the top and bottom faces of the piston. The piston rods are interchangeable so that the top piston rod can be exchanged with the bottom piston rod. The hydraulic actuator apparatus further includes top and bottom end caps, which sealably couple to the top and bottom faces of the hydraulic cylinder, and the end caps support connection to external components and have thru holes, which allow their respective piston rods to emerge from the hydraulic cylinder. The end caps are also interchangeable so that the top end cap and the bottom end cap can be switched. The hydraulic actuator apparatus is symmetric and can be rotated with respect to its connection to external components.

Abstract: A bellows insert (25) is shown, mountable inside a bellows for a vacuum powered tool and, in the mounted position, effective to locally limit the capacity of the bellows of compression in its longitudinal direction caused by a negative pressure introduced into the bellows. The bellows insert includes an engagement part (26) that has a shape complementary to the inside of the bellows and that, in the mounted position of the bellows insert, fills up some or all of the pleats of the bellows, within a limited area of the circumference of the bellows.

Abstract: A piston has a piston head, a piston pin support projecting from the piston head, and a mantle wall connected to the piston head. The mantle wall is formed with two tubular pieces that are disposed concentrically relative to one another and which are connected at a periphery of the piston head. A hollow space is formed between the tubular pieces.

Abstract: A piston pump is provided comprising a cylinder with an inner cylinder wall. The piston pump comprises at least one working space including fluid intake and fluid outlet, a piston including a piston rod and a piston head. The piston head includes a lateral surface facing the cylinder wall, a front surface facing the working space, a rear surface and at least one piston head channel. Furthermore, the piston head's lateral surface is provided with a first projection and a second projection extending round the entire circumference of the lateral surface and in contact with the cylinder wall, thereby forming an annulus which is defined by the first projection, the second projection, the cylinder wall and possibly the cylinder head's lateral surface between the first and the second projections if the piston head is designed so that the projections are provided with an axial spacing between them.

Abstract: A piston and cylinder assembly suitable for use in positive displacement machines (10) and capable of minimizing power losses resulting from friction and fluid leakage over a range of operating parameters. The piston (14) is reciprocably disposed within a cylinder (16) having a uniform diameter. The piston (14) has a bearing surface (30) that defines a diametrical clearance with the cylindrical bearing surface of the cylinder (16) of up to about two percent of the cylinder diameter. The diametrical clearance defines a lubrication gap (26) and a hydrodynamic seal between the piston (14) and the cylinder (16). The piston (14) further has alternating crests (34) and valleys (36) defined in a nominally cylindrical shape (28) of its bearing surface (30). The crests (34) and valleys (36) are oriented and spaced on the bearing surface (30) to define a wavy surface form (32) along the entire axial length of the bearing surface (30).

Abstract: A piston pump is provided comprising a cylinder with an inner cylinder wall. The piston pump comprises at least one working space including fluid intake and fluid outlet, a piston including a piston rod and a piston head. The piston head includes a lateral surface facing the cylinder wall, a front surface facing the working space, a rear surface and at least one piston head channel. Furthermore, the piston head's lateral surface is provided with a first projection and a second projection extending round the entire circumference of the lateral surface and in contact with the cylinder wall, thereby forming an annulus which is defined by the first projection, the second projection, the cylinder wall and possibly the cylinder head's lateral surface between the first and the second projections if the piston head is designed so that the projections are provided with an axial spacing between them.

Abstract: A compact hydraulic cylinder may include a pressure chamber and a reservoir in coaxial, in-line arrangement relative to one another. The pressure chamber and reservoir are separated from one another in use by a piston and hydraulic seal. The piston may be withdrawn to a position in which the pressure chamber and reservoir are in fluid communication through a channel formed in the wall of the cylinder, which may be used for bleeding the pressure chamber. The piston may include a actuator shaft that extends through the reservoir. A follower adjacent the distal end of the shaft seals the reservoir from the exterior of the cylinder.

Abstract: A piston for a compressor for use in hermetically encapsulated small-type refrigerating machines, with a cylinder-jacket-like sealing and guide surface section (1a, 2) as well as at least two substantially bridge- and cylinder-jacket-sector-like sealing and guide surface sections (6) of the piston skirt allowing the guidance of the piston in the cylinder as well as sealing the crankcase relative to the sealing or compression chamber and other sections of the piston skirt comprising a recess (3, 7).

Abstract: A compressor comprising a cylinder (1) with an axially reciprocating piston (5) which compresses gas in the cylinder. At least two circumferential rows of flat fan spray nozzles (10) spray water into the cylinder during compression. Each nozzle is arranged such that the spray is in a plane substantially parallel to the axis (4) of the cylinder and is directed towards a central region of the cylinder.

Abstract: A refrigerator with a regenerator having a good and stable cooling function comprises: a cylinder having a circular inner surface and being made of a material having a low heat conductivity and a high hermetic sealing performance; a displacer having a circular outer surface having a slightly smaller diameter than the inner surface of the cylinder, forming a main gas passage there through, and containing regeneration material therein, the displacer being disposed in the cylinder to be reciprocally movable in the axial direction the cylinder and forming an expansion space at one end of the cylinder; a groove pattern formed on one of the outer surface of the displacer and the inner surface of the cylinder, for forming an auxiliary gas passage for supplying gas into and recovering the gas from the expansion space, the groove pattern including a groove at least partially formed along the direction intersecting the axial direction of the displacer, such as a helical groove, the groove allowing a gas flowing through

Abstract: A piston with a skirt shaped to accommodate distortion by changing thermal and load conditions is further modified to increase stability and broaden load distribution to reduce contact forces and wear by providing maximum radii lines on either side of a longitudinal thrust plant with reduced radius regions forming apparent concavities therebetween.

Abstract: A universal plunger for oil well pumps, which universal plunger includes a symmetrical plunger body having a longitudinal bore, a pair of threaded flange nipples projecting from end flanges located on each end of the plunger body, a pair of spaced O-ring seats provided inwardly of the end flanges, respectively, the O-rings seated in the O-ring seats, a plunger body segment of reduced diameter extending between the inner sets of O-rings and a "Teflon"-hydrocarbon composition disposed between the spaced inside O-rings, the plunger body segment and that portion of the inside surface of the oil well pump barrel which faces the plunger body segment, for sealing and lubricating the universal plunger in the pump barrel.

Abstract: A brake system of the type having a disc-type wheel brake hydraulically operated by a master cylinder through connecting lines is disclosed. The system includes a member which divides the wheel brake into two chambers, one adjacent to the brake piston filled with a hydraulic fluid specifically formulated for meeting certain expected operating conditions in the wheel brakes. The second chamber is connected to the hydraulic lines and is filled with a second fluid specially formulated for meeting certain other different expected operating conditions in the lines and master cylinder.

Abstract: Apparatus and method for maintaining viscous liquid sealing substances such a grease adjacent and in contact with seals utilized in pneumatic cylinder-and-piston actuators for oil and gas well swabs, the structure including a piston member which is slideable on the piston rod and which includes an external O-ring for sealing engagement between the cylinders and the piston member and an internal O-ring which is in sealing engagement between the piston member and the piston rod. The piston member is resiliently urged by a compression spring towards the actuating piston and the viscous liquid is trapped between the actuating piston and the slideable piston member. A further like slideable piston member may also disposed on an extension of the piston rod on the opposite side of the actuating piston which is also urged towards the actuating piston. Viscous liquid is trapped between the latter slideable piston member and the actuating piston.

Abstract: Apparatus for sealing the gap between a piston and engine cyinder wall of either a reciprocating engine or a reciprocating compressor. The apparatus includes a plurality of functionally-identical, gas-bearing-supported seal blocks that locate in a slot running circumferentially around the engine piston. Gases fed from the engine chamber to the gas bearing carrying the load on the seal block in the direction of piston travel. The seal block includes a gas accumulator cavity for gas storage. An orifice feeds gas from the gas accumulator cavity to the gas bearing interfacing between the seal block and the engine cylinder wall. The apparatus also includes a reaction piston having gas communicated thereto from the engine chamber.

Abstract: The multidose syringe is provided with two pistons which are attached by a string to move simultaneously. A groove in the barrel for delivering fluid into and from the innermost fluid chamber is provided with baffles to create turbulence in the fluid flow to preclude entry of air into the fluid chamber between the pistons during filling of the syringe.

Abstract: A fuel injection pump for internal combustion engines has at least one pump working chamber which is defined on one side by the end face of the pump piston and the wall of the cylinder, and on the other side by a screw closure, the screw closure comprising a stopper containing a plug. The stopper can be tightened onto the cylinder by a sealing sleeve, and the stopper preferably comprises an outer threaded ring and an internal threaded sleeve soldered into the latter.

Abstract: A gas-liquid piston accumulator having improved piston lubrication by providing a plurality of blind hole lubricating passages around the periphery of the piston.

Abstract: The pressure accumulator (10) comprises a cylindrical housing (12) having a bore (14) with a piston received slidably therein. The piston (30) has an H-shaped cross section and includes a reduced diameter portion (34) extending longitudinally along the piston (30), and a sealing device (36, 38) disposed at each end of the reduced diameter portion (34). A cylindrical sleeve (44) is received in the reduced diameter portion (34) such that each end of the sleeve (44) abuts a respective sealing device (36, 38). The housing (12) has an exterior circumferential groove (20) with an O-ring (26) therein, and a radial opening (22) extending between the circumferential groove (20) and bore (14).

Abstract: A reversing and adjustment mechanism, especially for a reversible plough adapted for hydraulically adjustable furrow width and hydraulic reversing of the plough, wherein the reversing and adjustment mechanism comprises a hydraulic cylinder (8) with a "hydraulic memory" for adjustment of the furrow width. The oil chambers on both sides of the ordinary piston (15) in the adjustment cylinder (8) communicate with a reservoir (24) via two pilot-controlled check valves (26, 25) with open passage toward the adjustment cylinder (8) and a second direction-control valve (10). The chamber (31) in the adjustment cylinder (8) between the rear head and a freely movable piston (17) communicates on the one hand with a hydraulic cylinder (7) for reversing the plough, preferably with the rod end thereof, via a first check valve (14) with open passage toward the reversing cylinder (7), and on the other hand communicates with the reservoir (24) via a flow-control valve (28) and a first direction-control valve (9).

Abstract: The invention relates to an intensifier using liquid, comprising at least one cylinder which has plural pistons and a lubricating chamber between them.

Abstract: A means and apparatus for transfer of pressure energy from a first fluid at high pressure to a second fluid at lower pressure via a piston mounted for free floating movement within a cylinder communicating on one side with the first fluid and at the other side with the second fluid and in which contamination of the second fluid by the first fluid is prevented during energy transfer by exposing the one side of the piston to clean fluid for substantial equalization of pressures on opposite sides of the piston before exposure of the piston to the first fluid at high pressure.

Abstract: An improved valve actuator is provided for employment in environments such as subterranean wells where highly corrosive gases and fluids are contained in the well fluid which is normally pressurized and employed to operate the actuator. The bias element opposing the pressure induced movements of the piston unit of the actuator is disposed in an isolation chamber defined between two axially spaced, radial shoulders provided on the piston and having sealing engagement with the bore of the cylindrical wall, thus defining constant volume annular chamber that is isolated from the highly corrosive fluids and gases. The isolated chamber moves with the piston and thus does not provide fluid pressure opposition to the fluid pressure induced movement of the piston.

Abstract: The piston of a hydraulic cylinder is provided with a corrugated running surface composed of angularly disposed ribs and valleys therebetween, the ribs bearing against the relatively smooth bore of the tubular casing in which the piston reciprocates. Whereas the ribs on the piston provide a corrugated running surface bearing against the bore, the cylinder head, in which the piston rod is journaled, is formed with a similarly corrugated running surface.