Abstract: The hydraulic piston with a depressurized groove is capable of translating in a cylinder and includes a fixed skirt, an axial compression face which forms with the cylinder a fluid chamber, and an axial working face which cooperates with a transmission; the piston also includes a seal, a depressurized radial groove emerging onto the surface of the fixed skirt, an axial decompression duct fitted inside the skirt which emerges in the vicinity of the axial working face, and a radial decompression duct which depressurizes the radial groove in communication with the axial decompression conduit.

Abstract: An articulated coupling is provided for a piston sealing device for a piston which includes a fixed skirt and a sliding skirt interconnected by a mechanical inter-skirt connection for axially compressing a continuous extensible segment under the action of a sliding skirt spring, the coupling replacing, on the one hand, the fixed skirt by a ball-joint skirt and providing, on the other hand, a troncospherical piston end which cooperates with a skirt troncospherical bearing surface provided on the ball joint skirt while an articulation unit interposed between the inter-skirt mechanical connection and the piston and/or between the connection and the sliding skirt.

Abstract: A leak-proof damper with a self-diagnostic feature. An auxiliary oil reservoir body is disposed externally with respect to the damper cylinder and generally adjacent the rod seal, wherein the auxiliary oil reservoir body is concealed by an end cap. The maximum volume of oil retainable by the auxiliary oil reservoir body is predetermined to coincide with a volume of oil which may be lost from the interior of the damper cylinder and yet the damper will still function properly. The auxiliary oil reservoir body may be a seal body having an internal cavity providing an oil retention volume or an absorbent body having an absorbency capacity that provides an oil retention volume.

Abstract: A piston for an internal combustion engine has a piston head, a piston skirt, and a circumferential recess configured between the piston head and the piston skirt. The piston has a piston base body and a piston ring element. The piston base body has a crown region of a combustion bowl and the piston skirt. The piston ring element has a piston crown, a wall region of the combustion bowl, a circumferential top land, and a circumferential ring belt with ring grooves. The piston ring element has a circumferential cooling channel between the wall region of the combustion bowl and the ring belt, closed with a closure element. The piston base body and the piston ring element have a circumferential joining seam in the region of the combustion bowl, by way of which seam they are non-releasably connected with one another.

Abstract: A piston including a crown and a skirt extending generally axially away from the crown. The skirt includes a pair of opposed skirt panel portions and a band spaced away from the crown and extending generally around a perimeter of the piston. The piston further includes a pair of strut assemblies, each strut assembly including a pair of struts which converge in a radially outward direction. Each strut terminates at or adjacent to one of the panel portions.

Abstract: A gyroscopic rotary engine includes a rotary disc used as a cylinder block; a cylinder head on which medium inlets and medium outlets are arranged in a spaced relation; wherein at least two arched cylinders are disposed on the rotary disc in an equally spaced-apart relation; a gyroscopic unit disposed obliquely on the rotary disc relative to an axis of the rotary disc, the gyroscopic unit comprising a rotation shaft and pistons positioned symmetrically about the rotation shaft and having the number corresponding to the number of the arched cylinders, the pistons being disposed in the respective arched cylinders and firmly secured to the rotation shaft by respective connecting rods; and the rotary disc rotatably engaged with the cylinder head.

Abstract: The present invention relates to a multi-part piston (10) for an internal combustion engine, having an upper piston part (11) having a piston crown (13), and a lower piston part (12), whereby the lower piston part (12) has pin boss supports (32) and pin bosses (18) connected with them, whereby the upper piston part (11) and the lower piston part (12) each have an inner (21, 25) and an outer (22, 26) support element, which elements delimit an outer circumferential cooling channel (29). According to the invention, it is provided that the inner support elements (21, 25) delimit a cavity (31) that is open toward the pin bosses (18), and that the cavity (31) is provided with a separate cooling oil collector (35) that has at least one cooling oil opening (37, 38).

Abstract: An anti-rotation wire lock for use in a piston to reduce rotation of the anti-rotation wire lock while seated inside a wrist pin lock groove of the piston. The anti-rotation wire lock includes a wire lock body which curls from a first end of the wire lock body and a second end which extends in a direction out of a plane defined by the curled wire lock body. In addition, wire lock tools are disclosed for inserting and removing the anti-rotation wire lock.

Abstract: A piston for an internal combustion engine wherein the piston includes a piston body fabricated from a metal and a piston head fabricated from a ceramic or ceramic composite material, the ceramic or ceramic composite piston head is press fit to the piston body and secured by an internal circumferential locking ring.

Abstract: While ceramic materials possess properties that make them suitable for use in fuel system components, they tend to be susceptible to failure when exposed to tensile stresses. The retention system described herein helps to reduce the tensile stresses experienced by a retained member by providing a retained member with an engagement structure, a multi-piece retention ring that engages the engagement structure, a resilient member coupled to the retention ring, and a retainer coupled around at least a portion of the retention ring and resilient member and spaced apart from the retention ring and/or resilient member by a gap. The retained member, retention ring, resilient member, and retainer are configured so that the retention ring is moveable in an axial direction relative to the retained member and so that the movement of the retention ring acts to expand the resilient member against the bias provided by the resilient member.

Abstract: A bolt securing assembly is provided for securing a piston bolt in a piston. The bolt securing assembly includes, but is not limited to a bolt received by an opening. The opening may be provided by a piston for an automobile combustion engine. The bolt is secured by a securing member in axial direction. The securing member comprises a spring force in axial direction. Since an unnecessary movement is prevented, but a necessary movement is allowed, the wear of the bolt securing assembly is reduced.

Abstract: A hydraulic piston and cylinder unit comprising the combination of a cylinder assembly defining a cylindrical chamber, a piston member mounted in the cylindrical chamber for reciprocating movement therein in response to movement of hydraulic fluid under pressure into and out of the chamber, and a piston rod member connected to the piston member for movement therewith and extending from one end of cylinder assembly. The members have meshing threads thereon configured to be meshingly interengaged when the members are rotationally moved into an assembled position relative to one another in one direction.

Abstract: Proposed is a two-part piston 1 for an internal combustion engine, having an upper part 2 that has a pin 31 having an outside thread 32 on the underside of its piston crown 4, and having a lower part 3, which is connected with the upper part 2 by means of a nut 29 screwed onto the pin 31. The lower part 3 has an elastically resilient upper base part 25, onto which an expansion sleeve 26, elastic in the axial direction, is formed, which has an opening 27 having a collar 28, which is directed radially inward, into which the pin 31 is introduced. An elastic compression sleeve 30 is formed onto the nut 29, which sleeve rests against the collar 28. In this connection, the elastic resilience of the base part 25, the expansion sleeve 26, the compression sleeve 30, the pin 31, and the piston crown 4 has the result that the screw connection has a flat characteristic line despite a low compression height of the piston 1, thereby imparting great strength to the screw connection.

Abstract: A piston for an internal combustion engine which comprises a piston body, and a ring element, which together form a basic piston body. When the ring element is screwed onto the piston body, it forms a ring shaped cooling channel which is closed off in a direction of the pin bosses by a projection of the basic body. The projection is structured in the form of an elastically resilient cup spring which is deformed when the ring element is screwed onto the body. This deformation and counter stress, contributes to the strength of the screw connection.

Abstract: A device having a rigid rod mobile in a translational and/or rotational movement, whereof one end penetrates inside a recess of a piston and is fixed by a swivel to the recess of the piston directly or via an insert. The insert is mounted inside the recess of the piston, with a mechanism for axially locking the rod or the insert relative to the piston. The locking mechanism includes a stop borne by the piston to provide axial locking along a direction corresponding to the mounting direction of the rod in the piston, and a washer borne by the insert or the rod. The washer has peripheral fins elastically deformable in the radial direction and is pressed against the inner wall of the recess of the piston by being deformed to lock the insert or the rod in the opposite direction.

Abstract: The invention relates to a piston for a hydraulic control device for a clutch, especially the clutch of an automobile, having a tubular metal sleeve with an internal transversal wall which is integral with the tubular body of the sleeve. A hydraulic chamber is defined towards the front of the sleeve where the piston is mounted so as to slide axially.

Abstract: A hydraulic master cylinder for a clutch or brake of a motor vehicle is simultaneously optimized for cost-effective mass production and for functional properties.

Abstract: Pump (10) especially for a rubber dinghy and the like has a cylinder (11) with a double-acting alternating piston (13) and a small oblong cylinder (15) alongside the first, closed by heads (24) with packings (26), the valves (31) of the cylinder (11) communicating with the environment and the valves (19) of the small cylinder communicating with chambers (60, 61) that form at the ends of the cylinder (11) so that, on operating the piston (13) by an overgear with crank, an electric motor or the propulsor of a rubber dinghy, compressed air is generated and this passing through a centrally situated branch (33) in the cylinder (19), can be supplied to the rubber dinghy.

Abstract: The invention relates to a piston pump (10) with a piston (20) axially displaceable in a bush (12). In order to keep the piston (20) captive in the bush (12), the invention proposes that an annular loss-prevention means (90), with conically protruding spring tongues (96), be inserted in the manner of a snap connection into a V-shaped groove (80) in the bush (12), whose spring tongues (96) resiliently press a groove side (98) of a groove (34) made in the piston (40) into the groove (34), engaging it from behind, when the piston (20) is introduced into the bush (12). (FIG.

Abstract: For locking against rotation a piston on a piston rod, the piston having a peripheral groove and at least one radial through-hole to be positioned over a notch, a locking clip with a first straight end part and a curved part has a first end part extending through the radial hole in the piston and a part of the curved part of the locking clip rests in the peripheral groove when in a piston-locking position.

Abstract: A piston/cylinder assembly for a reciprocating compressor has a piston comprising telescopingly connected first and second piston members. The first piston member is connected to a connecting rod. The second piston member is provided with a piston head and is connected to the first piston member in such a way as to be movable axially relative to the first piston member by a predetermined distance. A spring is interposed between the first piston member and the second piston member to yieldably urge the first and second piston members axially apart.

Abstract: A flexible plunger apparatus includes an elongated flexible member having a pair of opposite end portions and a longitudinal length extending between the opposite end portions, with the flexible member being adapted to flex in transverse relationship to its length and to undergo free movement through a hollow tubing of a well. The apparatus also includes a physical barrier producing mechanism attached to and extending between the opposite end portions of the flexible member for substantially separating gas under pressure in the tubing below the lower end portion of the flexible member from a slug of liquid in the tubing above the upper end portion of the flexible member. The physically barrier producing mechanism is carried along the interior surface of the tubing in a substantially sealing relationship therewith as the flexible member undergoes free movement through the tubing of the well in response to the pressure of the gas and opening of the tubing of the well at the earth surface.

Abstract: In order to reduce the weight and manufacturing cost of a piston for a hydraulic actuating cylinder, the piston, the piston rod and the external reinforcement cap are combined to form a unitary integral part. The unitary part is advantageously a single extrusion product. The piston is shaped so as to be able both to slide along the length of the inner cylinder wall, and to tilt upon deflection or lateral displacement of the piston rod in the bore of the cylinder, while still maintaining its hydraulic seal.

Abstract: A hydraulically-powered tightening and loosening spanner includes a ratchet wheel assembly, a retaining mechanism, a drive lever connected to a piston rod and fixedly supporting a guide, and a member rotating the ratchet wheel assembly and including a slide which supports one or more drive elements and is slidable along the guide during reciprocal motion of the piston.

Abstract: A piston for a fluid power cylinder, which possesses two separate piston parts, which are detachably set together in a joint region axially with a sealing action. Each piston part has a rigid carrying element, which is molded on a holding portion, which in its radially outer region has a lip seal comprising sealing material with rubber-elastic properties and serving for sealing on a piston running face. The respective lip seal and the holding portion associated with same are constituted by components of an integral elastic body comprising a sealing material with rubber-elastic properties. Such elastic body is molded on the respectively associated carrying element. The two elastic bodies are in sealing contact with one another in the joint zone.

Abstract: A piston for an internal combustion engine has a trunk portion and a crown portion slidably mounted above the trunk portion. The entirety of the trunk portion extends above the piston's wrist pin bore. A resilient element positioned the crown portion with respect to the trunk portion with sufficient force in a direction tending to separate the crown portion and trunk portion such that the crown portion will be placed in a position of maximum extension during at least some part of the combustion cycle.

Abstract: In an elongate tank for transport or for storage in bulk of semisolid and fluid material such as grease and oil. The tank has an outlet at one end thereof for discharging material contained therein and is of generally cylindric internal cross section. It has a generally cylindric piston sized to slide in the tank and adapted to be moved in a direction toward the outlet thereby to force the material in the tank through the outlet. The piston comprises a piston member which carries an annular elastic seal. The seal has an annular crown projecting radially outwardly from the piston member and engageable with the interior surface of the tank.

Abstract: An air pump for use with a chain-driven bicycle having a free wheel. The pump assembly comprises a pair of opposed cylinders and a double-ended piston rod mounted in a housing. The piston rod has a bearing slot, which engages a crank pin on a crankshaft driven by a sprocket. Rotation of the sprocket reciprocates the double-ended piston rod in the cylinders. The cylinders are each integrally formed with a manifold that uses an elastomeric band covering a passage from the cylinder interior to inside the manifold as a one-way valve. An enlarged diameter skirt on each cylinder allows air to enter the cylinder on each intake stroke. A cap defining the piston head is locked onto each piston and holds a seal in place on the piston. An integral clamp assembly allows the pump to be removably mounted on a bicycle chain stay. The lower run of the bicycle drive chain engages the drive sprocket of the pump assembly, and a chain retainer is used to maintain the engagement of the drive chain with the drive sprocket.

Abstract: A ceramic-metal composite structure which minimizes tensile ceramic loads and accommodates differences in thermal expansion characteristics between a metal member and a ceramic member without reliance on precise feature control for either member. The composite includes a mechanical retainer which allows a loose fitting relationship between the metal and ceramic members. The ceramic member is secured within a receiving bore in the metal member by the retainer in a manner which eliminates the need for precise machining of the ceramic and metal members. The metal member may be configured to accept either an internal or an external mechanical retainer element. The composite ceramic-metal structure of the present invention finds particular utility in forming a durable wear-resistant interface in internal combustion engine actuator or actuating components, such as compression brake master pistons.

Abstract: The improved aircraft brake piston cap assembly (40, 40') comprises an aircraft piston (10) having a pair of openings (46) extending through the piston (10) and a piston cap (42) with a flange (44) fitted around the circumference of the piston (10 ) and having a pair of openings (48) aligned with the openings (46) in the piston (10 ) . A safety wire (50 ) may extend through the openings (46, 48 ) and be wrapped about a portion of the circumference of the piston cap so that the ends (52) are intertwined (53) to retain the safety wire (50) in place and the cap (42) attached to the piston (10), or a solid or spring pin (60, 60') may be press fitted into the openings (46, 48) of one of the piston cap (42) and piston (10) to attach the piston cap (42) to the piston (10) . The improved piston cap assembly (40, 40') permits components within the piston (10) to be extended to axially longer dimensions, and provides an improved, efficient and reliable attachment of the piston cap (42) to the piston (10).

Abstract: A piston for a combustion engine includes an external cylindrical body having an inner cavity. In the inner cavity is a partly spherical little-end of a connecting rod and a fluidtight shell or hemispherical dome. An edge portion of the dome is annularly connected a lower part of the cylindrical body so that the shell or dome bears on the little-end along a closed circular contact line or band during rest or minimum pressure parts of the cycle of operation. Oil is supplied under pressure and through a check valve to into an interstice between the little-end and the shell above the contact line. An upper incompressible space is provided between an outer surface of the shell and the cavity. The shell is maintained taut in operation between the little-end and an annular zone by which the edge portion is connected to the lower part of the cylindrical body.

Abstract: A ceramic-metal composite structure which minimizes tensile ceramic loads and accommodates differences in thermal expansion characteristics between a metal member and a ceramic member without reliance on precise feature control for either member. The composite includes a mechanical retainer which allows a loose fitting relationship between the metal and ceramic members. The ceramic member is secured within a receiving bore in the metal member by the retainer in a manner which eliminates the need for precise machining of the ceramic and metal members. The metal member may be configured to accept either an internal or an external mechanical retainer element. The composite ceramic-metal structure of the present invention finds particular utility in forming a durable wear-resistant interface in internal combustion engine actuator or actuating components, such as compression brake master pistons.

Abstract: A shock-absorbing piston, a blank for the piston and a method for producing the piston include two parts being constructed radially symmetrically, but formed with outer and inner parts differing from each other. This offers great variability in the shaping of the functionally essential elements of the shock-absorbing piston.

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: In a disk brake actuated preferably hydraulically, a piston (5) is guided within a housing located in a caliper. When pressure is applied, the piston acts in such a manner against a brake shoe (15) bearing a brake lining (17) that the brake shoe (15) is pressed with its brake lining against the brake disk to be braked. The side of the piston facing the brake shoe has a pressure plate (13) which transmits the pressure forces and which moves transversely within its recess in the piston (5). The pressure plate (13) is mounted on the end of a tappet (25) extending axially inside the piston (5) and bracing itself at the end opposite the pressure plate by a disk (27) at the bottom (29) of the bore (31) accommodating the tappet, and is surrounded by a prestressed compression spring (37). Lateral movements of the pressure plate (13) cause tipping of the tappet (25) and, as a consequence thereof, a reset force exerted by the compression spring (37 ) on the tappet (25) and, thus, on the pressure plate (13).

Abstract: A vibration cancellation device is provided for an air motor with a reciprocating drive piston. The device consists of an anti-phase piston which is axially aligned with the drive piston and reciprocates in the opposite direction of the drive piston. In one embodiment, the stroke of the anti-phase piston is adjustable to permit optimizing its vibration cancellation characteristics.

Abstract: A piston for an hydraulic brake is of the kind comprising an insulating core member and a cup member, joined together by fastening means arranged between the core and cup members.This fastening means is constituted as follows. The base portion of the cup member has a central projection, while the core member has a central cavity which is open at the level of the outer projecting surface of the cup member and which is closed by an end wall forming the base of the cavity, with the projection from the cup member base portion extending through a hole in this base wall. An axially acting resilient means is engaged on the free end of the projection within the cavity and engages against that face of the wall which is directed away from the base portion of the cup member. The invention is particularly applicable to the control of hydraulic brakes, in particular for automotive vehicles.

Abstract: In a compressor which has a connecting rod comprising: a second eye (31) connected to the crank pin (12) and a crankshaft (7) and including a radial projection (32) with a longitudinal slot (33), said longitudinal slot (33) having at least two end faces (35) and two opposite lateral faces (34);a first eye (21) connected to the piston and including a rod (22) with an end portion, said end portion having at least two end faces (25) and two opposite lateral faces (24), said end portion being fitted in said longitudinal slot (33) so as to bring the end faces of the slot (33) and the rod (22) into contact therefore defining the axial distance between the centers of the eyes.According to the invention a clamp (40) preferably of spring steel, is fitted in the housing (28, 29, 38, 39) of the radial projection (32) of the second eye (31) and the end portion of the rod (22).

Abstract: A pull rod assembly comprising a pull rod having three peripheral grooves, a piston device including an adaptor ring and a seal ring, said piston device being mounted on the pull rod by a split ring retainer situated in one groove and extending into an interior groove in the adaptor and a resilient split ring retained in another groove and positioned to engage the piston device and to retain the seal on its adaptor.

Abstract: A hydraulic cylinder, piston and rod assembly wherein the piston is secured to the rod in an efficient and inexpensive manner. The piston includes a threaded interior which is secured to a corresponding threaded portion on the end of the piston rod. An opening through a portion of the piston is aligned with a recess within the end portion of the piston rod to permit the insertion of a locking pin into the aligned openings. Thereafter, a compression ring, which is pivotally attached to the locking pin, is slipped into a complementary groove that is provided on the exterior periphery of the piston end portion. This provides a positive connection between the rod and piston which tolerates dimensional variations and eliminates play.

Abstract: A vacuum type booster which includes a booster piston reciprocatively movable in a shell, a valve sleeve for a control valve fitted to the booster piston and having a disengagement preventive flange superposed on the piston, and a clamp plate engaged with pawls formed by cutting and bending portions of the booster piston for clamping the flange to the booster piston. The booster piston includes pairs of reinforcement ribs which cross the turning direction of the clamp plate and sandwich cutout holes resulting from formation of the pawls. A pair of the ribs on the rear side of the turning direction of the clamp plate permit the clamp plate to turn in a direction for engagement with the pawls and inhibits the clamp plate from turning in the disengaging direction. A space is provided between the outer peripheral part of the disengagement preventive flange and an engagement piece jointing part of the clamp plate body.

Abstract: A rod-piston connection uses a split ring, having two or more segments, provided with a plurality of shallow internal grooves which are adapted to mate with a corresponding plurality of shallow grooves on the piston rod, the outer periphery of the split ring having a tapered surface extending over the entire width of th split ring and adapted to mate with a corresponding wide tapered surface defined in a bore of a compression bushing which has a peripheral surface provided with threads which engage with an internal threaded surface in a cavity in the pistion. By applying a threading torque to the compression sleeve, a force is generated by the two tapered surfaces to force the compression sleeve into better contact with the pistion and to force the split ring into a better contact with the piston rod.

Abstract: The double acting hydraulic piston and cylinder assembly of the present invention utilizes a unique fastening mechanism for fastening the piston to the cylinder rod. The piston has a rod receiving opening through which the piston rod is fitted. The piston includes a piston groove which is aligned with an annular rod groove in the outer surface of the rod. Extending from the outer circumference of the piston inwardly to the piston groove is an access opening, through which a retaining wire is inserted. The retaining wire is wrapped around the piston rod and fits within both the piston groove and the rod groove so as to hold the piston against longitudinal movement with respect to the rod.The method of the present invention comprises inserting the retainer wire through the access opening in the piston and rotating the piston until the wire wraps around the piston rod.

Abstract: In split cycle cryogenic coolers the compression and the expansion stage are distinct from one another and are connected by gas conduits. The change of volume of the expansion chamber is obtained by a linear, periodical movement of a displacer. According to the present invention, one end of a linkage connecting the displacer with its driving piston is directly connected to the latter while the other end of the linkage extends into the displacer. That end has a circumferential groove in which is seated an elastomeric ring.

Abstract: A piston assembly and a method for manufacturing piston assemblies. The piston assembly comprises a piston body, a connecting rod, a wrist pin, and a retaining spring holding the wrist pin within the piston body and maintaining the connecting rod spaced from a sidewall of the piston body. The retaining spring includes a central member, first and second side members, and resilient tab means. The central member is located between the wrist pin and a head of the piston body. The first and second side members extend rearward from opposed sides of the central member, between the connecting rod and the sidewall of the piston body, maintaining the connecting rod spaced therefrom, and define aligned spring openings receiving the wrist pin. The resilient tab means extends forward from the central member, engages the head of the piston body, and urges the first and second side members into pressure contact with the wrist pin to maintain the wrist pin within the piston bore.

Abstract: A mud pump piston assembly is provided which facilitates replacement and secure holding of piston parts which wear rapidly. A double acting piston includes a piston rod, a pair of hollow piston members on the rod, and a pair of wear rings located between the piston members. The wear rings fit over a flange on the rod and are slightly separated.

Abstract: A piston having a crown and a body connected together by bolts. The bolts pass through an annular gap defined by a pair of concentric ring members located between the crown and the body. One of the ring members is relatively resilient and the other ring member is relatively rigid. Such a construction reduces fretting between the crown and the body when the piston is in operation in an engine.

Abstract: A piston and cylinder device wherein the piston comprises an annular metal core with a peripheral groove for receiving an annular seal. The metal core has a peripheral overlay of nylon which provides a bearing surface at each side of the peripheral groove and the overlay follows the contour of the periphery of the metal core including the walls of the peripheral seal receiving groove.

Abstract: A piston, such as that used in an axial and/or radial piston hydraulic translating unit, comprising a hollow-skirt portion having inner surfaces defining a substantially conical cavity filled with a core of lightweight material, the material being retained in place by snap rings resiliently mounted into annular grooves formed on the inner surfaces of the skirt portion, which mechanically interlock the core material with the piston.

Abstract: A power cylinder of the multiple stage telescoping type that is characterized by a plurality of telescoping piston and cylinder assemblies, each of which comprises a composite cylinder and piston sleeve construction and an end closure construction that provides an extension stop for the piston sleeve of the next adjacent stage. The apparatus is further characterized by a quickly detachable base plate construction which permits ready access to the interior components of the cylinder via the base end thereof.