Abstract: Disclosed herein are seal assemblies that may each include: a metal ring that may have a metal convex outer surface and two metal outer edges; a ring that may have a non-metal concave inner surface and two protrusions, each of the non-metal protrusions may have a surface facing one of the two metal outer edges, wherein: the metal convex outer surface may be disposed against the non-metal concave inner surface; and at least one of the two metal outer edges may be abutted against the inner surface of one of the two protrusions.

Abstract: A fluid end (15) for a multiple reciprocating pump assembly (12) comprises at least three plunger bores (61) or (91) each for receiving a reciprocating plunger (35), each plunger bore having a plunger bore axis (65) or (95). Plunger bores being arranged across the fluid head to define a central plunger bore and lateral plunger bores located on either side of the central plunger bore. Fluid end (15) has suction valve bores (59) or (89), each suction valve bore receiving a suction valve (41) and having a suction valve bore axis (63) or (93). Discharge valve bores (57) or (87), each discharge valve bore receiving a discharge valve (43) and having a discharge valve bore axis (63) or (93). The axes of at least one of suction and discharge valve bores is inwardly offset in the fluid end from its respective plunger bore axis.

Abstract: In a rocking piston type compressor, a piston rod 11 is rockingly slidable within a cylinder 10. The compressor is provided with a lip ring 20 and an expansion member 30. The lip ring 20 is configured to seal between the cylinder 10 and piston rod 11. The lip ring 20 is provided on a leading end portion 13 of the piston rod 11 and includes a bottom portion 21 in a circular plate shape and a lip portion 22 extending from an entire peripheral edge of the bottom portion 21 to an upper side in a height direction. The expansion member 30 is provided on an inside of the lip portion 22 and configured to outwardly expand the lip portion 22 at a side of an upper portion in the height direction of the lip portion.

Abstract: A piston and scraper assembly (26) for a high-pressure liquid chromatography column (1) is provided with a snap lock between the piston (5) and the scraper (25). The snap lock comprises a groove (23) in the piston wall (17), a complementary groove (39) in the inner face of the scraper (25) and a locking, sealing and biasing means such as a resilient O-ring (43) which fits into said grooves.

Abstract: Seal apparatus includes a cover seal having a body and an extending cylindrical sleeve with the sleeve including a radial internal groove. A piston is provided having a circumferential groove and a biasing element is disposed between the internal and circumferential groove. Surfaces, disposed in the internal and circumferential grooves, orient the biasing element in order to effect sealing between the housing and the sleeve and an axial force to provide latching or locking between the seal and the piston.

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: The present invention aims at reducing the amount of oil consumption in a piston using a piston ring continuously formed of resin without being provided with an abutment. A stepped portion is formed on a third land, which is located below a second ring having a construction wherein an outer ring continuously formed of polyimide without being provided with an abutment is pressed against a cylinder wall by a coil expander via an inner ring continuously formed of PTFE without being provided with an abutment. Oil spill ports are provided so as to allow communication between the stepped portion and an inner wall of the piston.

Abstract: A piston assembly for a double-acting engine such as a double-acting Stirling engine. A pair of sealing rings located on opposite sides of a sealing washer are positioned between a base section and a dome section of a piston head. These sealing rings are alternatively urged into sealing engagement with the cylinder bore as the piston reciprocates. A single sealing ring design is also disclosed in which the sealing ring is urged into constant sealing engagement by positive pressure accumulated with an interior cavity in the piston head.

Abstract: A peripheral sliding seal for sealing the liquid propellant in a cylindrical tank 10 containing a piston 14 for positive expulsion of the liquid propellant. The seal comprises a peripheral inward flange member 16 around the piston periphery adjacent the inner wall of the tank, an annular pressure ring 18 bonded to the flange member 16 and forming several recesses therewith, one recess containing a compliant sealing ring 20 and the other containing a shear seal 32 bonded both to the flange member 16 and to the entrance head 12 of the tank. The bonds prevent internal and external leakage of the liquid fuel during storage. Pressurization of the piston 14 permits the piston 14 to move and breaks the shear seal 32. The compliant-ring seal slides with the piston 14, the compliant ring 20 being pressed against the inner wall of the tank by resilient fingers 34 of the pressure ring 18 to form a sliding seal.

Abstract: There is disclosed herein a small and compact vacuum pump which serves as a portable vacuum source. The pump basically includes a cylinder coupled with a handle, and a piston in the cylinder coupled with another handle, along with a suitable valving assembly for allowing a vacuum to be drawn at an inlet of the pump. More particularly, there is also disclosed a vacuum release which can be attached to or form an integral part of the pump. The vacuum release comprises a closure member which can be moved upwardly and downwardly in a housing to close and open with respect to a valve seat and, respectively, allow a vacuum to be pulled or release the vacuum. The closure member is arranged to rotate and is biased by a suitable helical torsion spring to normally maintain the closure member in the closed position to therefore normally allow a vacuum to be drawn by the pump.

Abstract: Compression piston ring for internal combustion or compressor cylinder and piston comprising double layer of segmented ring sectors having free form circumferential curvature matching the cylinder bore. The double layers are adapted to effectively seal or minimize bypass with resilient means provided for maintaining ring cylinder engagement under light radial pressure.

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 device particularly suitable for sealing pistons of working cylinders and for sealing two machine components which can slide against one another is disclosed. A conventional sealing element consisting of low-friction, but not very elastic material, such as PTFE plastic material, and resting on an elastic support, is used. The cross-section of the sealing element in a direction of the sliding motion is U-shaped and encircles the support. The dimensions of the support and the sealing element are determined such that the support exerts prestress forces on the sealing element which try to bend the rim areas of the sealing element outward against the sliding surface for the sealing element. Consequently, an additional force component, directed toward the sliding surface, results for the pressure force which is exerted on the sealing element by the support and functions as a sealing force.

Abstract: A small and compact vacuum pump which serves as a postable vacuum source is disclosed. The pump includes a cylinder coupled with one handle and a piston therein coupled with another handle, along with a wafer valve assembly for allowing a vacuum to be drawn at an inlet of the pump. A previous version of the pump is improved upon by the use of different valve assemblies, to produce a more reliable, more easily assembled and less expensive vacuum pump. A vacuum release mechanism is provided operable with a finger of the hand about the handle.

Abstract: A latching and sealing device suitable for use as a cover seal for a plunger or piston in a syringe or plunger pump includes a cylindrical seal member having a body portion and lip-and-latch means for both sealably engaging a surrounding surface and latching to the piston. A spring disposed in between the lip-and-latch means and the piston provide a constant sealing pressure while allowing the piston and seal member to be moved within a bore. Sealing between the lip-and-latch means and the bore is enhanced by use of a berm and notches radially aligned with the biasing spring.

Abstract: Apparatus and method of improving the performance of a pump for pumping fireproofing material and the like viscous materials is disclosed wherein the pump is the type which includes a compression chamber (44) having an inlet (48) and an outlet (50). A piston cylinder (19) is disposed in fluid communication with the compression chamber and, a piston assembly (A, D, G) is carried in the piston cylinder driven in reciprocating suction and compression strokes. The piston assembly includes an extended piston (B,E) carried on a push rod (18) having a piston face (42, 61) terminating adjacent an inlet ball limit pin (52), having a reduced pin length of 5/16 inch, at the end of the compression stroke.

Abstract: A slide type vacuum pump has a cylinder bore with a cylindrical piston reciprocatingly slidably fitted therein and defining a vacuum pumping chamber. A seal element is housed in an annular groove around the piston defined by a radially extending annular surface and an axially extending cylindrical surface. The seal element includes an inwardly radially extending annular portion axially abutted against the annular groove defining surface and an axially extending cylindrical portion slidingly sealing against the cylinder bore. A first spring member has an inwardly radially extending annular portion axially abuttingly holding the annular seal element portion against the annular groove defining surface, and several axially extending resilient finger portions each angled outwards somewhat and springingly pressing the cylindrical seal element portion radially outwards against the cylinder bore to effect sealing therebetween.

Abstract: A reversible valve for reversible refrigeration cycle. The valve means used therein is a hollow cylindrical body longitudinally extending within the valve body. It has a pair of inclined annular walls projecting from around the hollow cylindrical body to define an annular chamber therearound in cooperation with the valve body such that the annular chamber communicates the suction tube selectively with either one of said pair of tubes.

Abstract: A reversing valve construction having a housing provided with a movable valve member therein that is interconnected to a piston unit having opposed piston heads that define a main chamber of the housing therebetween. The housing has end portions respectively cooperating with the piston heads to define a pair of opposed control chambers therewith, the end portions respectively having valve seats leading to the control chambers in directions substantially transverse to the direction of movement of the piston unit in the housing. Each piston head has a flexible seal member secured between a front disc member and a backing plate of the respective piston head so that an integral peripheral skirt of that seal member is urged into sliding and sealing engagement with an internal peripheral surface of the housing by an annular resilient O-ring member carried by the respective piston head and radially engaging and urging its respective skirt radially outwardly into the sliding and sealing engagement.

Abstract: A reversing valve construction having a housing provided with a movable valve member therein that is interconnected to a piston unit having opposed piston heads that define a main chamber of the housing therebetween. The housing has opposed ends respectively cooperating with the piston heads to define a pair of opposed control chambers therebetween, the ends respectively having valve seats leading to the control chambers. Each piston head has a flexible seal member secured between a front disc member and a backing plate of the respective piston head so that an integral peripheral skirt of that seal member is urged into sliding and sealing engagement with an internal peripheral surface of the housing by an annular resilient O-ring member carried by the respective piston head and radially engaging and urging its respective skirt radially outwardly into the sliding and sealing engagement. Such seal member for each piston head can be adapted to close a valve seat carried by a respective end of the housing.

Abstract: In a pump having a cylinder liner, there is a piston therein, a seal around the piston and rear wearband around the piston body to align the piston within the liner. An elastomeric seal ring is in sealing and sliding contact with the liner. A gap filler, with minimal axial creep and controlled radial creep, abuts the rear surface of the seal and maintains continuous contact with the liner thereby continuously closing the extrusion gap between the gap filler and the liner as the liner wears. The wearband has a plurality of angled grooves longitudinally traversing it. Abrasive particles are directed within and through the grooves in the wearband while a source of liquid is communicated into the piston body, through water channels in the gap filler and through the flowpaths in the wearband to create a vortex action which washes the liner wall. The wearband insures no metal to metal contact between the piston and liner and provides a constant piston gap between the metal piston and liner.

Abstract: A cylinder device has a main body having therein a cylinder having an inner closed end and an outer open end, a piston slidably fitted in the cylinder and having a small diameter portion on the inner end thereof, a liquid pressure chamber defined between the piston and the inner end of the cylinder, a cup seal fitted around the small diameter portion of the piston with a lip portion thereof directed toward the liquid pressure chamber and sealingly engaged with the cylinder, an annular retainer disposed in the liquid pressure chamber, a spring acting between the piston and the annular retainer to urge the retainer against the inner end of the cylinder, the configuration of the annular retainer being such that when the piston is at the innermost position in the cylinder the annular retainer engages the lip portion of the cup seal to prevent the lip portion from radially inward deflection.

Abstract: A reversing valve construction having a housing provided with a movable valve member therein that is interconnected to a piston unit having opposed piston heads that define a main chamber of the housing therebetween. The housing has opposed ends respectively cooperating with the piston heads to define a pair of opposed control chambers therebetween, the ends respectively having valve seats leading to the control chambers. Each piston head has a flexible seal member secured between a front disc member and a backing plate of the respective piston head so that an integral peripheral skirt of that seal member is urged into sliding and sealing engagement with an internal peripheral surface of the housing by an annular resilient O-ring member carried by the respective piston head and radially engaging and urging its respective skirt radially outwardly into the sliding and sealing engagement. Such seal member for each piston head can be adapted to close a valve seat carried by a respective end of the housing.

Abstract: A piston ring having a general shape of a cylinder with the first section in the shape of an annulus for engaging a portion of the surface of a piston to provide a fluid-tight seal with the piston and a second section in the shape of a thin-walled bowl with sealing means on the outer surface of the bowl for providing a fluid-tight seal between the ring and the cylinder wall. The ring is especially constructed for use at cryogenic temperatures of -320.degree. F and below.

Abstract: To permit dry operation of a piston within the cylinder, the cylinder is made of metal, and the piston is made of polytetrafluorethylene; the piston, preferably, is formed with an annular ring groove extending downwardly from an end face thereof to leave a circumferential lip, the groove having a spring located therein biasing the lip outwardly against the cylinder wall, to provide for sealing contact of the lip against the cylinder wall, which is additionally reinforced by pressure of the gas being compressed by movement of the piston within the cylinder, tending to expand the lip against the piston surface, at the time when the compression is highest, and sealing is the most desired.

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.