Abstract: A piston for an internal combustion engine is provided. The piston includes a piston body including an upper combustion surface, an annular side wall with a ring belt region, and a cooling gallery located within the piston body having a fluid inlet. A piston ring is located in a ring groove around the ring belt region and an alignment pin is secured in a hole in the piston side wall to restrict circumferential displacement of the piston ring. The piston body further includes a boss within the cooling gallery into which the hole and the alignment pin extend. The boss projects into the cooling gallery opposite the fluid inlet and is shaped to provide a flow splitter surface configured to divide cooling fluid flowing through the fluid inlet during use into first and second fluid flows and to direct the first and second fluid flows in opposite directions around the cooling gallery.

Abstract: A brake cylinder includes a pressure medium actuated brake piston delimiting a brake chamber and connected to a brake piston rod. The brake piston, together with the piston rod, swivels into positions tilted from a center axis of the brake cylinder during an actuation stroke. The brake piston is rigid and has a guide surface in the shape of a spherical surface of an imaginary sphere on its radially outer peripheral surface. The guide surface is guided along a radially inner cylinder wall of the brake cylinder with the center of the sphere lying on the center axis of the brake cylinder. The brake piston further has at least one elastic sealing element radially displaceable in a radially outer annular groove of the brake piston and delimiting an annular space together with a groove base of the annular groove on its side facing away from the radially inner cylinder wall.

Abstract: A first piston for high load is inserted into a housing so as to be movable vertically, and a second piston for low load is inserted into a cylindrical hole of the first piston so as to be movable vertically. An output portion projects from the second piston to above the housing. A first spring for high load and a second spring for low load are mounted in a spring chamber defined by both pistons and. Both springs and are mounted so as to urge the first piston and the second piston upward. A switching mechanism disposed in the pressure fluid chamber at a side opposite to the spring chamber, connects the first piston selectively to the housing or the second piston.

Abstract: A piston assembly includes an annular body defining a groove, with a ring disposed within the groove. The piston assembly includes a centering device disposed within the groove between an inner face of the ring and a root of the groove. The centering device centers the ring concentrically within the groove when the ring is in an uncompressed condition, prior to installation into a bore of an engine block, to prevent the inner face of the ring from moving radially outward beyond an outer edge of the groove when the ring is in the uncompressed condition.

Abstract: A combination of a piston and a chamber, wherein the chamber defines an elongate chamber having a longitudinal axis, the chamber having, at a first longitudinal position thereof, a first cross-sectional area thereof and, at a second longitudinal position thereof, a second cross-sectional area, the second cross-sectional area being 95% or less of the first cross-sectional area, the change in cross-section of the chamber being at least substantially continuous between the first and second longitudinal positions, the piston being adapted to adapt itself to the cross-section of the chamber when moving from the first to the second longitudinal position of the chamber. The piston may comprise an umbrella-like support structure or a fibre enforced deformable container comprising a foam or a fluid. The combination may be used in a pump, a linear actuator, a motor, or a shock absorber.

Abstract: A piston 1 contains multiple ring grooves 2, 3 on the outer circumference of the piston 1, and piston rings 4, 10 are mounted in the ring grooves 2, 3. The piston 1 contains oil path grooves 7, 9 extending respectively to the outer circumference of the piston 1 on the upper and lower surfaces of the lowermost ring groove 2, and an oil path groove 12 extending to the outer circumference of the piston 1 on the lower surface of the ring groove 3 just above the lowermost ring groove 2. The weight of the lowermost piston ring 4 is equal to or smaller than the weight of the piston ring 10 just above the lowermost piston ring 4; and expanders 5, 11 are installed on the rear side of the piston rings 4, 10 respectively.

Abstract: A piston designed for use in metering machines employed in the food, chemical and pharmaceutical industries. The piston preferably has a cylindrical body with an annular bead in an intermediate position, a cap made of material designed to form a seal against the cylinder wall, which cap is fitted onto the body, and an annular support with an expansion spring, housed in a groove in the inner wall of the cap, the cap having an annular bead on the free edge; a clamping ring with a groove designed to fit onto the annular bead of the cap and onto the annular bead on the piston body is provided to keep the elements joined together, and the ring also acts as a guide for the piston against the cylinder wall.

Abstract: A pad plunger assembly includes an elongated mandrel having a pair of opposite ends, at least one pad subassembly disposed about the mandrel and extending between the opposite ends thereof, a plurality of annular key ways and annular keys respectively defined on the mandrel and the pad subassembly, the key ways and keys interfitting with one another so as to impede the ability of a fluid to flow along the mandrel beneath the pad subassembly and adjacent to the mandrel and from one to the other of the opposite ends of the mandrel, and elements for securing the pad subassembly on and around the mandrel.

Abstract: The present invention pertains to mechanical engineering, and more particularly to cylinder and piston assemblies mainly intended for use in two-stroke internal combustion engines. The cylindrical surface of the piston (5) is provided with recesses (9) located between sealing rings (6) and containing spring-biased elongate members (8). These members provide elongate sealing and define together with seal rings (6) an enclosed sealed area on the surface of the cylinder (1) in the region of the gas distributor ports (2,3). The system described in the present invention may be used to prevent leakage of the last charge and the combustion products from a first port of the gas distributor to the second port through the gap around the piston (5).

Abstract: A shock absorber with an affixed or clamped-on piston ring for a piston-cylinder unit, whereby the piston ring covers a lateral surface of the piston and creates a seal with respect to the cylinder, characterized by the fact that the piston ring has a width which is greater than the lateral surface, so that there is a projecting end of the piston ring with respect to the piston, which projecting end is shaped into a spring end which is supported on the cover side on the piston.

Abstract: A piston ring assembly comprises a piston ring, a spring for providing an outward force on the ring, and a rail for engaging a cylinder wall. The piston ring is retained in a piston groove in a piston. During upward movement of the piston in a cylinder, oil above the ring face is forced between the first front surface and the top surface into the piston groove to an inner portion of the piston groove. During downward movement of the piston, the downward force urges cocking of the piston ring about the ring face to tilt the ring face away from the cylinder wall, leaving the lower front of the ring face in scraping abutment with the cylinder wall.

Abstract: An oil control ring assembly having a sealing ring and a scraping is disposed within a groove in a piston. The scraping ring assembly has a scraping end portion and spaced apart ends defining a gap. The sealing ring has a sealing end portion and mated spaced apart radially stepped ends defining a stepped gap. The sealing end portion is connected to the scraping end portion and the stepped gap on the sealing ring is offset from the gap on the scraping ring. A spring applies a radial force to the scraping ring which urges the end portion of the scraping ring into engagement with the cylinder wall and a reaction force moment about the end portion forces the end portion of the of the seal ring into contact with an upper surface of the groove. The oil control ring assembly simultaneously provides for side and gap sealing.

Abstract: A tong head assembly for a glass blowing machine includes multiple tong mechanisms. Each tong mechanism has a tong extending from the bottom of a cylinder. The tongs are adapted to grasp a blown container. The cylinders are mounted for independent rectilinear and angular movement in the tong head assembly in order to compensate for misalignment of the tongs with the glass container to be grasped.

Abstract: A piston with at least one compression ring, a top end and a longitudinally extending axis for an internal combustion engine. The piston includes at least one compression ring groove defined by first and second spaced lateral surfaces for receiving the at least one compression ring. The first lateral surface is located nearest the top end of the piston. At least one of the first and second surfaces includes a plurality of profiles extending circularly around the axis and having a depth in the range of 0.003 mm to 0.015 mm and a width in the range of 0.02 mm to 0.2 mm.

Abstract: The fluid seals on the currently available piston assemblies are ineffective for blocking the leakage of electrical signals between the piston and the cylinder. The present invention utilizes an electrically conductive split ring seated in an annular groove in a piston and an electrically conductive annular spring disposed between the split ring and the piston to resiliently urge the split ring into conductive engagement with the hydraulic cylinder while providing continuous electrical contact between the split ring and the piston to block the leakage of electrical signals.

Abstract: This invention relates to a fluid sealing mechanism for the inside diameter and/or the outside diameter of a piston-cylinder arrangement. This device results in substantially zero seal leakage path with low differential seal pressure required using only one piston ring, one ring groove, and very loose dimensional tolerances required on both the ring and related groove. This yields an inexpensive more positive seal for fluid piston-cylinder configuration used in industrial, commercial, and personal use. This device may utilize an insulator on the side walls and bottom of the groove openings.

Abstract: An impact motor comprises a housing (10) with a cylinder (11) therein, in which a reciprocating drive piston (40) via a gas cushion in a working chamber (44) of said cylinder (11) repeatedly drives a hammer piston (15) to impact on and to return from the neck (17) of a tool (20) carried by the machine housing (10). A piston groove (68) is provided adjacent to the front face (70) of the drive piston (40) and the peripheral part of said face (70) is rounded (71) towards said groove (68). A piston ring (41) is of steel having a temperature expansion coefficient substantially equal to the cylinder's (11) and is ground circumferentially to have a close sliding and sealing fit in the cylinder (11). The rounded (71) drive piston face (70) is adapted to the inner diameter of said ring (41) so as to permit the ring (41) to be forced into said groove (68) undeformed to ride on a elastically centering O-ring (69) of heat resistant rubber.

Abstract: Located in a stationary frame is a cylinder-piston unit, the piston of which is adapted to displace the bearing housing of a roll in a paper-making machine at right angles to the longitudinal axis thereof. The bearing housing is guided in the frame with the aid of linear guide-elements. The radial play between the piston and the cylinder-bore is greater than the transverse play between the said linear guide-elements. Furthermore, the axial length of the piston is less than the depth of the cylinder-bore. Whenever the cylinder-piston unit is relieved of its load, and the cylinder thus returns to its position of rest, it is centered in the cylinder-bore by means of a centering device.

Abstract: Pistons and associated piston rings are described for use in internal combustion engines. The piston and piston ring comprise an annular piston ring groove having two radially extending walls and an axially extending wall; a compression ring received in the piston ring groove for sealing engagement with an associated cylinder wall or liner; a recess in the compression ring extending in an outwardly direction; an auxiliary sealing ring in permanent but deflectable contact with the axially extending wall of the annular piston ring groove and penetrating the recess in the compression ring; the arrangement being such that the auxiliary sealing ring does not physically limit the extent of movement of the compression ring in the annular piston ring groove. Pistons are described where two conventional compression rings are replaced by one. Test results are also presented.

Abstract: A servomotor is actuated by a pressure medium and has a piston reciprocated in the cylinder, the piston being mounted by a piston rod that extends through a cylinder end wall. The piston has a piston member bearing against the cylinder and is mounted for radial movement relative to the piston rod by a pair of piston guide plates that extend on opposite sides of the piston member. The guide plates are mounted by the piston rod for axial movement therewith.

Abstract: A piston-ring arrangement for use in an internal combustion engine including a cylinder with a piston axially displaceable within the cylinder and at least one piston ring guided in the cylinder. The cylinder, piston and piston-ring are made of a ceramic material. The piston ring is formed of two circumferentially extending parts and is mounted in a groove in the circumferentially surface of the piston. The groove has a depth greater than the corresponding radial depth of the piston ring so that a spring element can be positioned between the base of the groove and the piston ring for biasing the piston ring radially outwardly. The spring element can be annular member with a corrugated shape or a multi-part ceramic member shaped to provide a biasing action.

Abstract: It is a question of a piston and cylinder unit comprising a cylinder barrel defining a piston space, a piston able to run axially in said barrel with a support action due to a peripheral bearing surface of the barrel. The piston includes at least one annular running belt which is coaxially arranged thereon along part of the length of the piston. The belt has a surface facing radially outwards which makes contact with the inner bearing surface of the barrel with sliding fit to support the piston, while an inwardly directed surface of the belt bears on an outer peripheral surface of the piston, which is spaced from the bearing surface of the barrel. The belt further has an inwardly directed retainer spur fitting into a groove-like peripheral recess in the piston. The belt is made of a material with resiliently elastic properties and is interrupted at one position on its periphery so that in the fitted condition of the belt there is a closed interruption able to be opened out for fitting purposes.

Abstract: An internal combustion engine includes a piston mounted for reciprocating motion within a cylinder and sealed with respect thereto. The piston is connected to a crankshaft by means of a connecting rod, pivotal connections being provided between the connecting rod and crankshaft and between the connecting rod and piston. An oil ring is provided in a circumferential groove in the wall of the piston, said oil ring being split so that there is a gap in the ring when it engages the wall of the cylinder. An interconnection is provided between the connecting rod and oil ring by which tilting of the connecting rod upon upward movement of the piston will reduce the gap so that the load applied by the oil ring on the cylinder wall is reduced, the oil ring being permitted to expand against the cylinder wall upon downward movement of the piston.

Abstract: The seal, for use especially in non-lubricated, high-pressure, as compressors, in a one-piece, continuous sleeve which envelopes a reciprocable piston for sealing against the piston, or against the cylinder in which the piston translates. One end of the sleeve effects the sealing engagement, and the other end is spring-loaded to maintain the engagement. During operation of the compressor, or the like, it is the high-pressure gas which urges the seal into sealing engagement.

Abstract: A sealing ring device is provided for a fluid valve having a piston (2) reciprocating within a cylinder (1), wherein the piston (2) includes a valve cone (2c) adapted to contact a valve seat (11). In order to seal the inner space of the cylinder (1) located behind the piston (2) from an inlet/outlet passageway (A), a resilient sealing ring (5) is disposed in an annular groove (4) opening into the cylinder (1) around the rear end (2a) of the piston (2). A press ring (7), which extends above the rear end (2a) of the piston (2), contains the sealing ring (5) in the annular groove (4). A spring element (8) rests on the press ring (7). A piston rod (3) is guided in slidable manner through the piston (2). A stop (9) is attached to the rod (3) above the rear end (2a) and opposite the top side of the spring element (8).

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 two ring piston and piston ring assembly has an upper thin steel compression ring and a lower ring which is thicker than the compression ring and which acts both as a compression ring and an oil control ring. The lower piston ring is made of a material which is more conformable than steel, for example a plastics material, which may be reinforced. In this way, effective sealing is provided using only two piston rings, while the frictional forces between the piston and an associated cylinder are reduced.

Abstract: A rack-and-pinion steering gear structure for a vehicle including a rack housed within a cylinder driven by means of a pinion shaft, comprising: a bolt having a threaded portion screwed in a threaded hole formed in one end face of the rack and a shoulder linked integrally with the threaded portion and smaller in diameter than the rack but greater in diameter than the threaded portion; and a piston housed within a groove formed by the shoulder of the bolt, the seating surface of the bolt head, and the end face of the rack, with clearances with respect to the groove in the axial and radial directions.

Abstract: A piston-cylinder arrangement, particularly useful for the press shoe of an extended nip press. The cylinder is a fluid pressure cylinder with a piston, which is fluid pressure reciprocated, disposed in the cylinder chamber. The cylinder and piston are polygonal around their peripheries. A circumferential groove in the cylinder wall carries a plurality of sealing pieces which are urged outwardly of the groove and against the periphery of the piston. The sealing pieces comprise corner pieces disposed at the corners of the polygonal cylinder and second sealing pieces joining the corner pieces. Where the corner and second sealing pieces meet around the periphery of the cylinder, they have overlying, overlapping surfaces that are oriented perpendicular to the reciprocation of the piston. A spring in the groove may urge some of the pieces outwardly toward the piston.

Abstract: The mandrel of a fluid lift plunger carries pads retracted from a tube string by the continuous bias of collapsing springs. A control rod is displaceable relative to the mandrel causing a change in the force of detent springs which exert a continuous radially outward bias on the pads. In the detent held position assumed by the control rod during upward plunger travel, a higher detent spring force is exerted on the pads to overcome the collapsing springs and hold the pads in wiping contact with the tube string.

Abstract: An improvement for a variable volume device in the form of a rectilinear case having disposed therein a rectilinear outer piston structure and a rectilinear inner piston structure within the outer piston structure, the inner piston being carried for rotation on a crank shaft and in turn inducing a reciprocal movement of the outer piston structure in the case, the improvement comprising rollers positioned between the outer piston structure and the case, and the inner piston structure and outer piston structure to facilatate thrust and force accomodation therebetween, and sealing strip means positioned in sealing relationship between the outer piston structure and rectilinear case, and inner piston structure and outer piston structure, and particularly an embodiment in which the sealing strips means of the inner piston structure bear against the side portion of the outer piston structure sealing ring means and a bearing plate positioned to support the rollers, whereby the rectilinear innerrunning pistons may be

Abstract: The piston and cylinder of a hydraulic power booster are provided with opposed longitudinal grooves effecting a pocket for a series of rollers axially aligned and on an axis parallel to that of the piston-cylinder axis. A leaf spring in the piston groove maintains a radial bias on the rollers towards the cylinder groove. The rollers effect a sliding guide or key between the piston and cylinder to prevent rotation or twisting of the piston in the cylinder.

Abstract: A hydraulic actuating and locking device includes a locking piston within a cylinder, an actuating piston within a cylinder in the rear surface of the locking piston and a pressure multiplier connected to the space behind the piston. A passage, constituting a high pressure cylinder, connects the space behind the piston to an oil reservoir and is adapted to receive and be sealed by the high pressure piston of the pressure multiplier.

Abstract: A piston assembly is mounted at an inner axial end of the toothed portion of a rack within a tubular extension of a hydrosteering gear housing. The piston assembly includes a piston ring floatingly supported with axial clearance on the base portion of a mounting ring axially fixed to the rack at said inner axial end.

Abstract: A servo cylinder having a piston of the kind having spaced sections which move into an enlarged diameter low pressure bore portion of the cylinder is provided with a gasket assembly for each piston section in the form of an elastic sealing gasket having a resiliently flexible radial flange extending from an integral collar and supported by a rigid ring having a certain circumferential clearance from the collar to permit radial movement for misalignment compensation. The gasket may be formed in the cross-sectional shape of an L or of a T. Where an L-shape is used, a single support ring is provided and where a T-shape is used a support ring on each side of the radially extending flange which forms the leg of the T oriented 90.degree. would be used. The ring or rings are protective of the radial flange in either direction of movement of the respective piston.

Abstract: A piston for a pneumatic cylinder having a guide and sealing annular member extending around the circumference of the piston, and a resilient bearing member biassing the guide and sealing member in a direction for sealing engagement with the internal surface of the cylinder. The guide and sealing member has a plurality of axially consecutive, radially projecting sections for surface contact with the internal surface of the cylinder, each pair of adjacent sections defining a cavity therebetween. The material of the guide and sealing member between adjacent radially projecting sections of the guide and sealing member define a hinge-like connection therebetween.

Abstract: A plunger comprises a carrier and a hollow sleeve portion extending around a portion of the carrier. The sleeve portion rests between longitudinally spaced radial shoulders of the carrier. A portion of the carrier disposed within the sleeve is radially spaced from the sleeve to form a gap, which gap is pressurized to counteract pressures acting exteriorly on the sleeve portion. The gap can communicate with the environment surrounding the plunger so that external pressures pressurize the gap before or during plunger operation. The carrier may comprise a body portion and a cover portion which are connected by means of extensions which project through the sleeve portion. The sleeve portion can be formed of a material having a smaller coefficient of expansion than the body portion or cover portion.

Abstract: An actuator, and a system employing the same, which will continue to operate after deformation of a portion thereof which deformation would normally restrict movement between the piston and cylinder of the actuator. The piston or gland of the actuator is constructed so as to include segmented flanges which will fracture responsive to forces applied to them upon engagement of the deformation. Slots defining the segments are filled with a rubber-like material which is bonded to the piston or gland thus providing a solid structure to enable appropriate sealing while not interfering with the fracturability of the segments.

Abstract: Vacuum pump of reciprocating piston and cylinder type. Cylinder is stepped to have front large diameter portion and rear small diameter portion. Piston has enlarged head portion sliding in front portion of cylinder and rear portion sliding in rear portion of cylinder. Front end of cylinder is closed to form high vacuum pumping chamber swept by front face of piston head. Gas enters the high vacuum pumping chamber through side wall of cylinder and can be exhausted through exhaust valve in closed front end of cylinder. Rear annular face of piston head sweeps lower vacuum chamber in cylinder behind the piston head. A gas transfer passage extends through cylinder wall from front end of high vacuum pumping chamber to port in cylinder wall so as to transfer gas from high vacuum chamber to lower vacuum chamber when piston approaches end of forward stroke. Gas is transferred through transfer duct at pressures lower than required to open the exhaust valve.

Abstract: The seal, for use especially in non-lubricated, high-pressure, as compressors, in a one-piece, continuous sleeve which envelopes a reciprocable piston for sealing against the piston, or against the cylinder in which the piston translates. One end of the sleeve effects the sealing engagement, and the other end is spring-loaded to maintain the engagement. During operation of the compressor, or the like, it is the high-pressure gas which urges the seal into sealing engagement.