Abstract: A coat layer formed on the outer perimeter side surface of a piston comprises a fluorocarbon resin and a binder as main components, and further contains 0.05-12% by volume of a wear resistance additive with a Mohs hardness of 2.0-5.0. This provides a piston compressor piston having a coat layer with excellent wear resistance.

Abstract: An adjustable packing gland assembly is mounted for adjustable engagement with a seal and a packing in a fluid pumping apparatus for sealing against fluid leakage about reciprocating plungers and like pumping elements, the adjustable packing gland also stabilizes the pumping element. A stuffing box is formed in the pump housing and spaced packing gland shoulder bolts bottom out on that housing. A packing gland is disposed in the stuffing box and is slidably mounted on the spaced adjustment studs, each of the shoulder bolts having adjusting nuts and pipe sleeves disposed for precision adjustment of the packing gland. Bearing against the plunger on either side of the packing and seal are guiding elements made of a low wear material which possesses lubricity as against the plunger. The upper guide may be integrally formed with the gland. An eccentric liner is made of a similar material as the guides, rendering it a low wear item in need of little or no lubrication.

Abstract: A compressor includes a piston and a shoe, which contact and slide on one another. The piston includes a sliding surface, on which a solid lubricant film is formed. The shoe includes a sliding surface that slides on the first sliding surface. A soft film that mainly contains soft metal is formed on the second sliding surface. The solid lubricant that forms the solid lubricant film is a solid lubricant other than a soft metal.

Abstract: A compressor piston that smoothly slides in a cylinder bore and a coating method for manufacturing such pistons. Coating material is applied to a piston to form a coating layer. The principal components of the material include fluororesin and a binder. The coating layer is not ground. Therefore, fluororesin, which migrates to the surface of the coating layer, is not removed by grinding, which permits the piston to resist friction.

Abstract: A film forming method for a compressor and a part of the compressor to be formed with a film are disclosed. A paint container (36) is arranged above a rotary holding mechanism (34) with a swash plate (15) of the compressor mounted thereon. A lubrication paint (37) in the paint container (36) is dripped on the end surface (152) of the swash plate (15) through a dripping unit (38). The swash plate (15) is rotated at high speed by the operation of a motor (M) so that the surplus portion of the lubrication paint (37) on the end surface (152) is removed by centrifugal force. The lubrication paint (37) remaining on the end surface (152) with the surplus portion thereof removed by centrifugal force has a uniform film thickness.

Abstract: A swash plate (3, 18) and pistons (6, 17) included in a swash plate type compressor are made of an aluminum alloy as a base material. Rotation-preventive interfering surfaces (6d, 17d) of the pistons (6, 17) which interfere with another member to restrain the pistons from rotation about their axes are coated with a film of a solid lubricant. Sliding contact surfaces (6a, 17a) of the pistons (6, 17) in sliding contact with surfaces defining cylinder bores (5, 16) are coated with a film of a solid lubricant. When the rotation-preventive interfering surfaces (6d) of the pistons (6) come into impulsive contact with the outer circumference (3b) of the swash plate (3), the outer circumference (3b) of the swash plate (3) is coated with a lubricating film.

Abstract: Chromium nitride coating of machine components such as reciprocating pump plungers for continuous sliding contact with non-metallic packing and gasket materials greatly increases the performance life of fluid seals. In an air driven reciprocating constant pressure pump, exterior surfaces of the pump plunger are coated with chromium nitride to a thickness of seven to ten microns. The coating resists failure from repeated sliding contact against non-metallic packing and gasket materials for at least four million pump cycles, with no evidence of cracking or release of metallic particles which would embed in the packing or gasket material and score the plunger. In lower pressure pumps, interior walls of a housing against which a sliding gasket bears, when coated with chromium nitride, greatly increase the seal life of the sliding gasket.

Abstract: The invention is related to a swash plate compressor in which the wear resistance and the lubricating ability of the surfaces of the swash plate which are in contact with the shoes can be enhanced and maintained for a long period of time. In the swash plate compressor, a soft surface coating 21 is formed on sliding surfaces of any of a swash plate or shoes and the coarseness at ten point mean roughness of the surface of the substrate is made to be 8 &mgr;mRz or less, and preferably 5 &mgr;mRz or less, and more preferably 3 &mgr;mRz or less. Even if the soft surface coating 21 is partially worn or exfoliated by a sliding load, since the temperature of the soft surface coating 21 is increased by frictional heat and the soft surface coating 21 is fluidized, the worn or exfoliated portions are repaired. The soft surface coating 21 is preferably composed of a coating layer containing molybdenum disulfide.

Abstract: A single-headed piston type swash-plate-operated refrigerant compressor is provided with a swash plate mounted on a rotatable drive shaft and having front and rear opposite surfaces, single headed pistons arranged on the rear side of the swash plate to reciprocate in respective cylinder bores, and front and rear shoes to be held in slide-contact with the peripheral parts of the front and rear surfaces of the swash plate to engage a tail end part of each of the single headed pistons with the swash plate in which the front and rear surfaces of the swash plate are provided with respective uppermost layers having physical surface properties different from one another. A front uppermost and a rear uppermost layer of the swash plate are formed of a sprayed coating of, for example, a copper-base material and the rear uppermost layer is coated by a solid lubricant layer containing a solid lubricant, such as molybdenum disulfide, at least in a part of the solid lubricant.

Abstract: A reciprocating compressor in which the piston is axially movable within a cylindrical cavity formed on an aluminium cylinder; the piston being provided with a sealing element made from composite plastics material, an oil-scraper element made from cast iron, and a guide element made from composite plastics material; the sealing element being disposed in a first seat formed in the side wall of the piston close to an upper surface of the piston, the guide element being disposed in a second seat formed in the side wall of the piston close to a lower edge of the piston, and the oil-scraper element being disposed in a third seat formed in the side wall of the piston between the first and second seats.

Abstract: A piston-type compressor has seven cylinder bores formed in a cylinder block which is formed in a compressor housing. A piston is slidably disposed within each of the cylinder bores. Each of the pistons includes a cylindrical main body and an engaging portion axially extending from the cylindrical body. A drive shaft is rotatably supported in the cylinder block. A bearing couples the plate to each of the pistons, so that the pistons reciprocate within the cylinder bores upon rotation of the plate which is tiltably connected to the drive shaft. A recessed portion is formed in an interior of the cylindrical body of each piston so that the cylindrical body forms a C-shaped cross-section perpendicular to longitudinal axis of the piston. Therefore, the configuration obtains lightweight pistons while simultaneously maintaining the efficiency of the compressor.

Abstract: A piston for a compressor. The piston has a lubricating coating that slidably contacts with an inner surface of the cylinder bore. The layer is formed on the surface of the piston. The layer is formed by transferring a liquid material to the surface of the piston using printing techniques such as screen printing and roller coating.

Abstract: A compressor having a cylinder bores and pistons are disclosed. Each piston moves in the associated cylinder to compress gas therein. Each piston slides on an inner peripheral wall of an associated cylinder to seal a compression chamber. Each piston includes an outer peripheral surface and cavities. The outer peripheral surface has a seal to seal the cylinder and a pressure receiving surface to receive reaction forces from the wall of the cylinder. A low friction layer is formed on the pressure receiving surface. The layer facilitates the sliding movement of the piston with respect to the cylinder.

Abstract: A piston-type fluid displacement apparatus includes several pistons, each of which is slidably disposed within one of several cylinder bores. A plating layer, which includes a self-lubricating material, is coated on a peripheral surface of each piston. At least one annular groove is formed on a periphery surface of each piston, and, at least one piston ring is disposed within the annular groove of each piston for sealing a gap between the piston and the cylinder bore. Thereby, the piston-type fluid displacement apparatus may be simply manufactured at a reduced assembly cost while simultaneously prolonging the life of the piston rings and while reducing or eliminating a decrease in compression efficiency during the operating life of the piston-type fluid displacement apparatus.

Abstract: A vacuum pump is provided with at least one cylinder having a cylinder liner and a piston mounted for reciprocating movement within the cylinder liner. The piston is connected to a crankshaft for reciprocating the piston and the piston is provided with a piston head having a flat face and an upper end thereof. A valve plate having a flat surface facing the flat surface of the piston head is biased into engagement with the end of the cylinder liner whereby upward movement of the piston the flat face of the piston head makes full contact with the flat face of the valve plate to move the valve plate away from the cylinder liner. The piston is provided with two annular lip seals having an L-shaped configuration disposed in opposite directions at opposite ends of the piston in engagement with the cylinder liner.

Abstract: The device comprises a cylinder (3) and a piston (7) which is guided free of contact relative to the cylinder (3). A gap seal (12) is provided between the lateral surfaces (15, 14) of the cylinder (3) and of the piston (7). The gap seal (12) has a very thin and uniform annular cross section. The lateral surfaces (14, 15) of the cylinder liner (4) and of the piston (7) are essentially smooth and comprise a material with a linear thermal coefficient of expansion which is lower relative to steel. The precise maintenance of the sealing gap and the central guidance of the piston (7) in the cylinder liner (4) is ensured through two guides (8, 9) connected rigidly with the housing (5). These guides (8, 9) are elastic in the direction of the central axis (2) of the piston-cylinder unit and highly rigid transversely to the central axis (2).

Abstract: A piston for a fluid-actuated, percussive, down-the-hole drill is provided with self-lubricating bearings and self-lubricating seals. The piston includes an elongated body member terminating in a front end and a back end and having a longitudinal bore therethrough. A bearing and seal combination is positioned adjacent each end of the piston and an undercut portion of the piston body extends therebetween. The bore and undercut portions of the body form a portion of fluid passageways in the drill, when the piston is reciprocated in the drill. The seals float in their grooves, being movable axially, radially and circumferentially. The bearings are substantially nonmovable axially and radially.

Abstract: A piston for a fluid-actuated, percussive, down-the-hole drill is provided with self-lubricating bearings and self-lubricating seals within the drill to provide a drill requiring no oil lubrication.

Abstract: A piston for a shock absorber as may be used in an automobile comprises a piston body, and a piston ring which covers the outer periphery thereof. One end of the piston ring is formed as a bend, which is received in a first receiving groove formed in the piston body. The first receiving groove comprises opposing end faces which extend in a direction orthogonal to the axis of the piston body, and a bottom surface which connects together the both end faces. The tip of the bend is disposed in abutment against the corner defined by one of the end faces and the bottom surface. As compared with the prior arrangement in which the end face comprising the corner is formed as a tapered surface, the tip of the bend is less likely to be displaced radially outward, thus reducing the possibility that he bend may be disengaged from he first receiving groove.

Abstract: A swash plate type refrigerant compressor comprises a compressor housing enclosing therein a crank chamber, a suction chamber and a discharge chamber. A swash plate is tiltably connected to the drive shaft and has two sliding surfaces sides thereof. The swash plate includes a sliding surface which engages a plurality of pairs of shoes. The shoes couple the swash plate to the pistons so that the pistons may be driven in a reciprocating motion within the cylinder bores upon rotation of the swash plate. At least one groove is formed in the sliding contact surfaces between the swash plate and the shoes. The groove captures and retains lubricating oil in the refrigerant in response to the rotation of the swash plate.

Abstract: A fluid end including a cylinder has a bore extending therethrough. A plunger is reciprocally disposed in the bore. A packing element is disposed in the bore to seal the annular space between the plunger and bore and includes a lubrication ring formed of metallic fibers and impregnated with a solid lubricant, a seal ring formed of a high-lubricity polymeric material, and means for positioning the lubrication and seal rings in the bore.

Abstract: A piston and ring assembly operative within a cylindrical bore wall to retain pressurized fluid to one side of the assembly, the piston having a crown and an annular side wall for movement along the bore wall.

Abstract: The invention relates to a high accuracy flowmeter for testing and calibrating flowmeters and the like, and more particularly to a positive displacement flowmeter which may include a cylinder (12), a piston (10) within the cylinder (12) which makes a clearance seal with the inside of the cylinder, an encoder (40) associated with the piston, and a control valve (V) for controlling the supply of a fluid flow (A1) to be measured. More generally, the flowmeter includes a channel for receiving a fluid flow so as to move the piston (10) within its enclosure (12); and a device (36, 38, 40) for detecting movement of the piston and generating electrical signals representative of the fluid flow to be measured. The movement of the piston is detected as a function of a known volume of the enclosure traversed by the piston, and a measured variable elapsed time over which the piston traverses the volume. Preferably, the flowmeter system includes a damping device (FIGS. 6A-6D) which may be mechanical, pneumatic, or fluidic.

Abstract: A piston and method of manufacture is disclosed wherein a low friction plastic material D is sprayed upon a molded cylindrical metallic member, having a single intermediate annular groove C, forming a coating having wear surfaces A and B on each side of the groove, and a sealing ring E carried in the annular groove.

Abstract: A fluid cylinder has improved wear rings in a combination that includes a tube having a tubular wall and first and second end caps. The tubular wall defines a cylinder bore that has a central axis. Each end cap also has a bore extending along the central axis. A piston assembly is mounted in the cylinder bore with a piston rod mounted in the bore of one of the end caps, so that the piston assembly is slidable along the central axis. The piston assembly includes a piston head that has a reservoir defined by an annular recess opening toward the tubular wall. The reservoir houses a prepacked lubricant. One wear ring closes off the annular recess from the tubular wall. The wear ring seal has a plurality of radial apertures extending therethrough, through which lubricant is capable of flowing to lubricate the piston assembly. Another wear ring closes off a reservoir in the bore of an end cap and functions as the first mentioned wear ring also to lubricate the piston assembly.

Abstract: Piston has upper and lower portions. The upper portion includes a cylinder engaging surface, such as a piston ring, comprised of solid lubricant. The lower portion includes a cylinder engaging surface comprised of liquid lubricant control means. The distance between the upper and lower cylinder engaging surfaces is sufficient to provide a temperature differential of at least 316.degree. C. (600.degree. F.) between the upper and lower portions during normal engine operations. This differential is adequate to maintain the temperature of the cylinder at the bottom ring reversal point at a temperature below the breakdown temperature of a liquid lubricant when the temperature of the cylinder liner at the top ring reversal point is at a temperature above the breakdown temperature of the liquid lubricant.

Abstract: A lubricated cylinder wall in which an oil permeable cylinder ring is located on the inside surface of a cylinder. Oil from an oil supply channel located behind the oil permeable ring supplies the ring with oil. When the oil pressure in the oil supply channel is greater than the pressure inside the cylinder, oil is forced through the oil permeable ring and onto the inside surface of the oil permeable ring. Because the ring is located in the cylinder wall at a location above the bottom dead center location of the piston, upward motion of the piston inside the cylinder sweeps oil from the inside surface at the oil ring over the inside surface of the cylinder. The oil ring is installed in the cylinder by coiling it to a smaller diameter then the cylinder, placing the coiled ring in a groove on the inside surface of the cylinder, pressure fitting the coiled ring into the groove, and then honing the inside surface of the ring to be flush with the inside surface of the cylinder.

Abstract: The very high pressure piston pump can compress a conveying agent (20) to a pressure of approximately 22 kbar. The high pressure sealing comprises a pressure-compensated ice sealing, which operates free of leakage and with reduced friction. To reduce the generally very high frictional forces in the ice sealings, a rotation is superimposed on the translation of the piston (10). The entire machine may be regulated by means of a microprocessor, depending upon the operational parameters and the feed efficiency. Its very high pressure seal has a long service life, even under continued operation in very high pressure ranges.

Abstract: Cooperating slidable aluminum alloy members comprising first and second slidable aluminum alloy members that have a slide portion and slide surface, respectively, which slide relative to each other. The slide portion of the first slidable aluminum alloy member is being comprised of a fiber-reinforced aluminum alloy. The reinforcement fiber used for the first slidable aluminum alloy member being a mixture of an alumina fiber and a carbon fiber. The slide surface of the second slidable member is provided with a layer of heat resistant synthetic resin in which are dispersed a solid lubricant and an abrasion resistance improving agent.

Abstract: A pneumatic operating device, e.g. for controlling valves, includes a cylinder (2) in which a piston (12) is movable. The piston has an axially extending rack part (11) having teeth which engage with teeth on an operating element (10) arranged in the cylinder wall (2b) for rotation transversely of the longitudinal axis of the piston and passing sealingly through said cylinder wall. The piston (12) is provided on the side opposite its rack part with a recess (24) for receiving a part of a spring (26) for the return movement of the piston. The recess (24) extends substantially into the rack part (11) of the piston, preferably through a distance of such length that it extends axially approximately up to or beyond a radial line perpendicular to the piston axis through the center of rotation of the operating element even when the piston is in a position in which the spring is compressed to its maximum.

Abstract: A spherical piston for high-pressure applications. By shifting the o-ring oove to the pressure side of the major diameter of a spherical piston such that one edge of the groove is the major diameter, a very close fitting spherical piston that will not have metal to metal interference is created. Contrary to traditional spherical pistons, the spherical diameter of the present invention is less than the diameter of a cylinder wall. Elimination of metal to metal interference between the piston and the cylinder wall permits the piston to be made of harder metal than the cylinder wall without concern for damage if the piston cants on its axis within the cylinder.

Abstract: A compressor motor has a flywheel connected directly to a motor shaft which drives two opposed pistons that are simultaneously compressed so that the bearing loads are balanced. A double inlet blower is connected to said shaft and has one inlet for drawing cooling air through a crankcase for cooling the connecting rod bearings. A second inlet draws air through a vent formed in a shroud member. The blower discharges the air from both inlets into the shroud member which then directs the air to the cylinder sleeves and heads for cooling purposes. The cylinder, piston skirts and piston rings are self-lubricated by containing a fluorocarbon thereby substantially reducing the heat generating friction between said members.

Abstract: A flexible boot surrounds a piston rod and is sealed at one end to the free end portion of the piston rod and at its other end to the rod end of the associated cylinder. The head end of the cylinder is connected to a source of gas under pressure and the interior of the boot communicates freely with the interior of the cylinder at the rod end thereof. A check valve is provided for relieving the pressure in the boot when it reaches a predetermined value.

Abstract: A small high speed direct connected motor compressor has a unitary piston and piston rod whereby the piston wobbles in the cylinder as the crank shaft rotates. The wobbling piston is sealed to the cylinder by a flanged disk of Teflon which forms both a seal and mechanical guide for the piston and which runs without lubrication in contact with a low-friction, surface-coated cylinder of high heat conductivity. The circular rim of the Teflon cup is warped from circular outline to elliptical outline twice per revolution while maintaining its seal with the walls of the cylinder. The structure involves small clearance spaces with consequent good efficiency.

Abstract: A pump having a piston tip member which fits a cylinder bore sufficiently loosely that abrasive particles in fluid being pumped do not excessively wear away the cylinder walls and piston tip member, the fit being sufficiently close, however, as to provide substantial and effective pump pressure, the liquid that by-passes the tip member being retained by a sealing assembly surrounding the piston rod for assuring that substantially all of it returns to the forward side of the piston during a return stroke.A paint spraying assembly using the pump described.