Abstract: A compression piston ring is provided, in particular a piston ring suitable as a second piston ring in a three-ring piston ring set, which piston ring has convex sections and concave sections alternating in the circumferential direction in a middle running face region in relation to the axial height, wherein the concave sections form profile recesses in the convexly crowned running face.

Abstract: A piston assembly is provided with a piston head retaining structure. The piston assembly includes a piston shaft and a piston head disposed around the piston shaft and providing a piston head face that faces a cylinder wall. The piston assembly further includes a piston head mount element arranged adjacent to the piston head and mounted around the piston shaft and a tensioning device that generates an axial tension between the piston shaft and the piston head.

Abstract: A probe seal for a female hydraulic coupling member has both internal and external pressure-energized seals. The outer wall or opposing ends of the seal have one or more pressure-energized seals for sealing between the body of the probe seal and the body of a coupling member in which the probe seal is installed. Annular, L-shaped, T-shaped or angled grooves in the inner wall of the seal form cavities and sealing projections that can be urged in an inward, radial direction by fluid pressure within an associated cavity to increase the sealing effectiveness between the body of the seal and the probe of a male hydraulic coupling member inserted in the receiving chamber of the female coupling member.

Abstract: In a fluid pressure apparatus, a packing includes an annular seal member made of an elastic material, and support rings made of a low-friction material, which are mounted on an outer circumference of the seal member. The seal member includes, on an outer circumference thereof, a sealing projection that contacts an inner surface of the slide hole. The support rings are disposed on both sides of the sealing projection, and protrude beyond the seal member in the axial direction. Outer circumferential surfaces of the support rings always contact the inner circumferential surface of the slide hole. When a transverse load does not act on a piston as a partitioning member, the inner circumferential surfaces of the support rings do not contact the outer circumference of the piston. When a transverse load acts on the piston, the inner circumferential surfaces of the support rings contact the outer circumference of the piston.

Abstract: A piston pump includes a pump mechanism configured to compress fluid sucked from an inlet port by increasing or decreasing a volume of a pump chamber which faces a front end of a piston by reciprocating the piston housed in a housing, a feed mechanism including a feed ring mounted to an annular groove provided at an outer periphery of the piston and following a motion of the piston, a feed chamber formed between the feed ring and the housing, and a valve portion. The piston pump includes a pressure wall provided at the piston and configured to contact the feed ring to axially move the feed ring, and a restriction portion provided at the feed ring and configured to engage with an outer periphery of the piston at a position approximate to the pressure wall for restricting a radial displacement of the feed ring on the piston.

Abstract: An annular mating portion extends from a fastening surface of a fastening nut. The mating portion has an inner diameter set to be substantially equal to an outer diameter of the portion of a piston in which an accommodating groove is formed. In a state in which the mating portion is inserted into the accommodating groove, and an inner circumferential surface of the mating portion slides in contact with a circumferential wall of the accommodating groove, the fastening nut is mated with a threaded portion, and a lip seal is held between the mating portion and the accommodating groove. This fixes the lip seal to the piston.

Abstract: A hydraulic linear drive, particularly a hydraulic transmission actuator, having a piston/cylinder unit, in which an actuating piston longitudinally displaceably arranged in the cylinder housing divided into at least two pressure chambers which can be acted upon by hydraulic oil by way of control conduits. A piston rod is connected with the actuating piston, and a sealing element is arranged on the actuating piston to seal off the two pressure chambers from one another. The actuating piston has a two-piece construction and consists of a first and a second piston part between whose facing faces, a sealing element is arranged.

Abstract: A piston-chamber combination comprising an elongate chamber which is bounded by an inner chamber wall and comprising an elastically deformable piston comprising a container in said chamber to be sealingly movable relative to said chamber at least between first and second longitudinal positions of said chamber, said chamber having cross-sections of different cross-sectional areas at the first and second longitudinal positions of said chamber and at least substantially continuously different cross-sectional areas at intermediate longitudinal positions between the first and second longitudinal positions thereof, the cross-sectional area at the first longitudinal position being larger than the cross-sections area at the second longitudinal position, said piston including a piston body and sealing means supported by the piston body being designed to adapt itself and said sealing means to said different cross-sectional areas of said chamber during the relative movements of said pistion from the second longitudinal

Abstract: A piston includes a circumferential groove having a dynamic split seal ring having a flat axially facing surface, a static seal ring having a flat axially facing surface abutting the flat surface of the dynamic seal ring, and a spring mounted within the groove. The spring exerts an axial force on the static seal ring that serves to distribute the axial load with a static seal over the dynamic split seal, thereby preventing shuttling of the split seal within the groove and restricting the leak path of the seal. Preferably, the static seal ring is a polymer and can be an L-ring, a load ring with a flange that abuts the piston body, or flanged designs. In addition, a load ring can be fitted between the L-ring and the spring. The split seal ring has at least one radial spring mounted within the seal ring to create a radial force on the split seal ring. The piston can also include a sleeve that mounts to the piston body, the sleeve forming a wall of the groove.

Abstract: A banded cylindrical piston for use in fluid cylinders is produced by hot-forming a relatively thin, flat washer made of polytetrafluoroethylene (PTFE) onto a grooved piston. A hot-forming sizing tube has a beveled entrance end on which the washer is initially preheated, a first section of a greater diameter than the end diameter of a finished unit for preliminarily elongating the preheated washer as it assumes sleeve shape and a final hot-forming second section in which the PTFE material is forced to flow under pressure into the piston grooves. The cross-sectional configuration of the groove or grooves is such as to enhance flowability of the material during hot-forming toward and into contact with a side of the groove nearest the head end of the piston to improve the mechanical gripping effect of band to piston. The side of the groove nearest the head end of the piston is preferably at an acute angle relative to an adjacent land on the periphery of the piston.

Abstract: A piston for use in a hydraulic cylinder which is subject to sudden and extremely high shock load pressures and high temperature operating conditions is provided with a plurality of interlocking axially-spaced circumferential grooves. A relatively thin, flat washer of heat-formable fluoropolymer is snapped over a retaining ring integral with the piston and the piston is then moved axially through a heated hot-forming cylinder, causing the washer to conform to the cylindrical shape of the piston. At least one circumferential groove has a side wall which is undercut relative to its cylindrical surface to provide a locking angle. Preheating the washer prior to hot-forming the band and forming a sloping ramp in opposition to the undercut side wall result in improved flow of the fluoropolymer toward the undercut side wall. An additional advantage of the preheating is the formation of an improved band skirt with an improved, sharply-defined sealing edge.

Abstract: In a priming piston loading double acting pump for high viscosity materials, the shovel plate assembly is formed of a flexible, abrasion resistant disk or cup. The disk may be made from silicon rubber and the cup may be made from a glass filled Teflon polytetrafluoroethylene material. The clearance between the plate assembly and the intake cylinder is essentially zero to allow for a build-up of a vacuum as the plate assembly moves downwardly and out of the intake cylinder to greatly enhance the loading ability of the pump.

Abstract: A piston for use in a hydraulic cylinder which is subject to sudden and extremely high shock load pressures and high temperature operating conditions is provided with a plurality of interlocking axially-spaced circumferential grooves. A band of a heat-formable fluoropolymer is snapped over a retaining ring integral with the piston and the piston is then moved axially through a heated hot-forming cylinder, causing the washer to conform to the cylindrical shape of the piston. At least one circumferential has a side wall which is undercut relative to its cylindrical surface to provide a locking angle. A method of washer preheating prior to hot-forming the band results in better flow of the fluoropolymer toward the undercut side wall. The method of preheating also produces a band skirt with a relatively sharply-defined sealing edge.

Abstract: The high temperature and high pressure seal retainer ring (40) is a continuous ring (40) of polyetheretherketone having an inner diameter that is substantially equal to outer diameters of a rear portion of a movable piston (14). The ring (40) is generally wedge shaped and is received within a wedge shaped opening defined by a surface of a bore (12) receiving the movable piston (14) and a sloped axially extending surface (22) at the rear portion of the piston (14). The piston (14) includes a groove (18) adjacent the sloped axially extending surface (22) and receives therein a rubber seal (30).

Abstract: The present invention relates to a high pressure piston sealing system. More particularly, the present invention relates to a sealing system adopted for rigorous marine applications which prevent or inhibit the use of a seal lubricant.

Abstract: A dispensing apparatus comprises a pressurised dispensing container (3), a housing (2) for the container defining a bore, the container having a body (50) which is axially slidable in the bore, the container having a collapsible metering valve (8) located at a first end (6) of the body for dispensing metered quantities of fluid and actuated by axial depression of a valve stem (9) defining a dispensing flowpath, a valve actuator (11) fixedly connected to the housing at a corresponding first end (7) thereof and defining a further dispensing flowpath for product fluid dispensed through the stem, and trigger means (30) operable to urge the container body axially towards the first end of the housing such that the valve stem is depressed by relative movement together of the valve and actuator and thereby dispensing a metered quantity of fluid, wherein the container body defines a chamber (4) and the container includes means (5) dividing the chamber into a product fluid reservoir (25) communicating with the valve an

Abstract: It is a question of a multi-part piston more especially for use in double acting cylinder actuators. The piston has two piston halves that are mounted on a piston rod so as to be symmetrical about a contact surface between them. Each piston half has a metallic inner member with a radial anchoring projection, as for example in the form of a flange. On the inner member there is a molded casing of synthetic resin. Each piston half has a piston seal arranged in a circumferential groove in the outer surface of the casing.

Abstract: A lightweight and portable volumetric spirometer for measuring the volume of and rate of flow of air inhaled by human lungs. The device includes a movable piston within a first transparent cylindrical chamber provided with calibrated markings along its surface for measuring the volume of air withdrawn from the chamber. The first chamber communicates with a breathing tube assembly through which the user inhales. The breathing tube assembly is uniquely adapted so that the inhaled air flow is divided into two fixed portions, one portion of which comes from the chamber, the other portion of which comes from a second chamber communicating with the outside atmosphere. As air is inhaled, the piston rises to a height that can be related to the total volume inhaled. Preferably, there is a counterweight in the second chamber which also rises during inhalation to counterbalance the resistance to movement of the piston and which gives an indication of the rate of inhalation.

Abstract: A hydraulic piston cylinder device comprising a cylinder, a piston dividing the cylinder into two cylinder spaces (A and B), and valve members between the cylinder spaces and respective pressure medium pipes. The problem is to achieve a hydraulic piston cylinder device in which the pressure or tractive force of the cylinder is maintained even if the external pressure led into the cylinder would stop. To solve this problem, an elastic material is interposed between two piston parts, and is elastically compressible by the external pressure applied to the cylinder; and the valve members are coupled to each other so that when one of the valve members is closed the other cannot be closed.

Abstract: A useful sealing device which serves to fluidtightly seal a clearance between a cylindrical member and a cylindrical bore into which said cylindrical member is to be fitted. The sealing device comprises an annular endless resilient seal ring made of a resilient sheet-like material and having an inner diameter smaller than an outer diameter of a seal fitting portion on the cylindrical member. One of the opposite surfaces of the resilient seal ring is tightly fitted around the fitting portion of the cylindrical member in a facing relation to each other, whereas the other surface of the same is faced to the sealing surface of the cylindrical bore and at least a part thereof is placed in resilient contact with the sealing surface.

Abstract: Ram bodies mounted in transverse bores of a blowout preventer body with a longitudinal bore therethrough are operable by operating means extending through closures on one end of the transverse bores to move the rams to close off fluid communication through the longitudinal bore in the body and to retract the rams from the longitudinal bore. Removable seal means are provided on each ram body to seal with the transverse bore in which each ram body is mounted. Removable seal means extend diametrically across the front of each ram for sealingly engaging an elongate member in the longitudinal bore when the rams are closed. The removable seal means is retained in position by non-torquing means during use but may be readily replaced when necessary. Self energizing seal means on the ram body sealingly engage the transverse bores.

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 hydraulic mast digger has a kelly head with improved retaining and sealing features. The digger is of the type having a kelly with a bearing assembly mounted between the kelly and a bearing sleeve. The bearing sleeve is reciprocally carried in the hydraulic cylinder and moves in response to hydraulic fluid pressure. The bearing assembly allows rotation of the kelly with respect to the bearing sleeve. A cap is secured by threads to the bearing sleeve above the top of the kelly to define a piston. The cap has an upwardly facing shoulder located below the upper edge of the bearing sleeve. A retainer is rigidly secured to the cap and extends down into the space between the cap and bearing sleeve. A locking device locks the retainer to the bearing sleeve. Preferably the locking device includes a key that fits within slots formed on the retainer and bearing sleeve. A primary seal encircles the retainer.

Abstract: A piston-cylinder arrangement comprising a cylinder member and piston means mounted slideably therein, the piston means comprising a piston member and a packing member mounted on the piston member for movement therewith, wherein said packing member has first and second axially spaced radially outer surfaces dimensioned such that each contacts slidingly against said cylinder wall and wherein the piston means comprises a lubricant reservoir in communication with the space between said surfaces, which space is substantially closed by said cylinder wall.

Abstract: A multilayer seal comprising a stack of rings, some being made of elastomeric material and some being made of more rigid material, such as a metal. The elastomeric and rigid rings alternate in the axial direction of the stack, and the elastomeric rings are progressively thinner in the axial direction of the stack. Each ring is preferably bonded to the next successive ring in the stack. When the seal is in place between two opposed surfaces to be sealed against fluid pressure, the thickest of the elastomeric rings is arranged nearest the higher pressure end of the opposed surfaces.

Abstract: A piston, especially for a pneumatic cylinder, includes a disc-shaped piston head and a sealing element on the head, such element has at least one annular sealing lip extending outwardly of the peripheral sliding surface of the head, the sealing lip being of elastic and resilient material and being of conical form relative to a central axis of the piston head, an outer free edge of the lip thereby being capable of sealingly engaging the wall of the cylinder.

Abstract: A mud pump piston comprising an annular elastomeric ring having an annular circumferential surface defining an acute angle circumferential tip of relatively small area which engages the pump cylinder wall and an annular anti-extrusion ring connected to and displaceable with the elastomeric ring, the elastomeric ring being configurated to correspond with and rest against a dish shaped surface of the anti-extrusion ring presenting a bevelled or diagonal slope extending from the outside diameter (acute to the axis of the mud pump piston) spanning substantially more than half of the radial distance occupied by the annular elastomeric ring and the annular anti-extrusion ring, which diagonal surface merges with a flat surface normal to the axis of the mud pump piston whereby hydro-planing is reduced because of the increased unit pressure load on the small tip area, along a line contact, the tip is automatically wear compensating, friction is substantially reduced by reason of the smaller high pressure wipe area, lo

Abstract: An o-ring seal assembly in combination with a downhole pump and an o-ring collar. The seal assembly includes a special o-ring device and two coacting seal holding members which cooperate together to provide an o-ring groove, and which separate to enable an o-ring of this invention to be received therewithin. The special o-ring includes a resilient o-ring and a retainer. The o-ring has an annular face thereof bonded to a concave face formed on the retainer member. In one form of the invention the retainer member is in the form of a cylinder having an outer concave wall bonded to the inner annular face of the o-ring. In another embodiment of the invention, the retainer member is in the form of an apertured disc having an upper concave wall bonded to a lower annular face of the o-ring. The o-ring preferably is made of rubber or rubber-like material while the retainer member is made of metal and is vulcanized to the rubber o-ring.

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: A piston pump mechanism includes a plunger head slideably mounted within a cylindrical sleeve member. The plunger head has an upper portion forming a shoulder and a reduced lower portion around which an inner ring of resilient material is mounted. An outer ring of resilient material, such as tetrafluroethylene, for example, is mounted around the inner ring. A piston rod has an end coupled to the transverse face of the reduced portion of the plunger head in such manner to provide axial adjustment therebetween, and a pressure cap is mounted upon this end. The pressure cap has a cylindrical like peripheral rim for applying a progressively greater axial force against the inner ring, causing the inner ring of material to apply a progressively greater radial force against the outer ring, as the piston rod and cap assembly are axially adjusted toward the plunger head, until the outer ring of material seals against the interior wall of the sleeve.

Abstract: A caulking gun including a barrel having a dispensing tip on the outer end and a mechanism for releasably connecting the tip in sealing engagement with the outer end of the barrel. The barrel has a handle mounted on the inner end thereof with a trigger pivotally mounted on the handle. A rod extends within and from the inner end of the barrel with a piston on the rod and within the barrel. A dog having a hole therethrough and through which the rod extends to allow canting movement of the dog on the rod. The trigger has a lug thereon for engagement with one end of the dog to cant the dog in one direction on the rod to grip and advance the rod and the piston thereon in the barrel as the trigger is pivotally actuated. The handle carries a mechanism for canting the dog in the other direction free of gripping engagement with the rod when the rod is moved into the barrel whereby the rod and the piston thereon may be withdrawn from the barrel free of the dog for filling of the barrel.

Abstract: A simply constructed and inexpensive syphon for rapidly lifting liquid out of a container, the syphon consisting of a flexible plastic tube in which there is a spongy plastic piston attached to a flexible cord which extends out of one end of the tube so it can be manually pulled whereby liquid is pulled into the tube behind it.