Abstract: A piston for an internal combustion engine includes a piston crown and a piston skirt, and an oil gallery formed between the piston crown and the piston skirt. A gallery inlet to the oil gallery, and a plurality of gallery drain outlets are formed in the piston skirt. The gallery drain outlets have, circumferentially around the piston center axis, a non-axisymmetric arrangement in a distribution biased to an anti-thrust side of the piston.

Abstract: A pot-shaped, cold-formed steel brake piston as a pot which is open on one side includes a base and a wall including inner and outer walls, a radially inwardly configured groove is open in a radially outward direction and forms, radially at the inside, a groove bead projection. The open side of the pot ends as a bearing for a friction pad backplate. Interfaces integrated at the inside on the end side serve a) for the fixing between friction pad and steel brake piston and b) as support bearing for spring mounting the friction pad. An aspect is a further improved steel brake piston of the new generation. The minimum inner diameter dimin is axially set back in the direction of the base by a multiple of the length of a wall thickness s, and the minimum piston inner diameter dimin is formed by the groove bead projection.

Abstract: An improved piston forging for use in an internal combustion engine is disclosed. The piston forging comprises a crown, a pair of pin towers extending generally axially away from the crown, and a skirt extending generally axially away from the crown. The improved piston forging further comprises a plurality of grains flowing across the piston forging. The plurality of grains are reoriented during the forging operation into a configuration that follows the surfaces and features of the piston forging. More specifically, the plurality of grains are reoriented in a manner that is most beneficial to resist combustion and inertial forces that are enacted upon a machined piston during operation.

Abstract: A piston for an internal combustion engine has a plurality of recesses formed in a skirt including an upper, a lower, and a central portion. The recesses in the upper portion close to an upper boundary of the central portion have lower ends located upwardly at a given distance away from the upper boundary. The recesses in the central portion close to the upper boundary have upper ends located downwardly at the given distance away from the upper boundary. The recesses in the lower portion close to the lower boundary have upper ends located downwardly at the given distance away from the lower boundary. The recesses in the central portion closer to the lower boundary have lower ends located upwardly at the given distance away from the lower boundary. This enhances lubrication between the piston and an inner wall of a cylinder bore and reduces a friction loss of the piston.

Abstract: A galleryless piston having a reduced temperature during operation in an engine is provided. The piston includes an upper wall with an exposed undercrown surface. A ring belt and pin bosses depend from the upper wall, and a pair of skirt panels depend from the ring belt and are coupled to the pin bosses by struts. The piston includes an inner undercrown region and outer pockets extending along the undercrown surface. The inner undercrown region is surrounded by the skirt panels, the struts, and the pin bosses. Each outer pocket is surrounded by one of the pin bosses, a portion of the ring belt, and the struts adjacent the one pin boss. A plurality of holes extend through the pin bosses and/or the struts from the inner undercrown region to one of the outer pockets to convey cooling oil from the inner undercrown region to the outer pockets.

Abstract: A method for producing a piston for internal combustion engines, where the piston includes a circumferential trapezoid annular groove for receiving trapezoid rings with small axial dimensions the groove having a groove base with adjoining surfaces and groove flanks. The groove base with adjoining surfaces is created in a first method step by machining using a cutting steel tool and the groove flanks are created in a further method step. Also disclosed are a piston produced according to the method and a cutting steel tool.

Abstract: Exemplary pistons and methods are disclosed. A method may include depositing a scuff and seizure resistant material via a thermal spray method on the surface of a piston pin bore used in internal combustion engines. Exemplary pistons may have a crown and a skirt. The piston crown may define a combustion bowl and a ring land extending circumferentially around the combustion bowl, the skirt supporting the crown, the skirt including a pair of pin bosses, the pin bosses each defining a pin bore configured to receive a piston pin, each pin bore defining a pin bore surface extending circumferentially about the piston pin bore, the bore surface formed of a first material. The method may further include applying a coating comprising at least a second material different from the first material to the pin bore surfaces using a thermal spray process.

Abstract: A piston for an internal combustion engine is disclosed. The piston includes an upper surface configured to at least partly face a cylinder head of the internal combustion engine. The upper surface includes a combustion bowl surface, and a squish face having an internal edge disposed a first distance from the longitudinal axis along a radial direction. The combustion bowl surface includes a planar surface extending radially outward from the longitudinal axis of the piston, a first concave surface disposed outside the planar surface in the radial direction, the first concave surface having a first radius of curvature, and a second concave surface disposed outside the first concave surface in the radial direction, the second concave surface having a second radius of curvature, the second radius of curvature being smaller than the first radius of curvature.

Abstract: The invention relates to a die casting ring (1) internally fitted with radial teeth (11) to be engaged into matching seats (22) provided on a piston (2). This piston-ring assembly prevents mutual rotation or axial translation, in addition to ensuring an optimal seal against infiltration of liquid metal during the die casting process. When the ring has a cutout (10), it can be mounted accurately onto the piston because the teeth (11) allow the cutout to be positioned anywhere relative to the piston.

Abstract: The present invention provides a piston for a spark-ignition engine, comprising: a land part 18, an upper surface part of which has a crown part 26 forming a combustion chamber; a pair of skirt parts 20 extending downward from a peripheral part of the land part 18 and facing each other in a radial direction thereof; a pair of sidewall parts 19 coupling side end parts of the pair of skirt parts 20 to each other; and a pin boss part 21 that is formed in each of the sidewall parts 19. The present invention can inhibit the generation of HC produced at the time of combustion, while thermally protecting a top ring 30 fitted into a top ring groove 24a on an outer circumferential surface of the land part 18. The crown part 26 is configured by a flat base surface 27 and a bulging part 15 bulging upward above the base surface 27, and a thinned part 40 provided in the land part 18 is formed deep such that the deepest part thereof is positioned inside the bulging part 15.

Abstract: It is important to maintain the temperature in the ring pack area of the piston of an internal combustion engine below about 270° C. to maintain proper ring function and lubrication. Disclosed is a piston with a heat barrier groove between the piston top and the ring pack and a method to construct such a piston. The heat barrier groove extends inwardly toward the center of the piston a greater distance than the compression ring grooves. In one embodiment, a low thermal conductivity material is placed in the inner portion of the heat barrier groove and a split ring is place in the outer portion. In another embodiment, a gas is provided in the inner portion and the split ring is welded to the piston so that the inner portion of the heat barrier groove is sealed, i.e., welding at the upper and lower edges and at the gap.

Abstract: A piston assembly according to an aspect of the present disclosure includes a piston and a bushing. The piston includes a piston skirt, side panels, and a piston crown. The side panels define a pin bore for receiving a wrist pin. The pin bore has an inner surface including a cylindrical section and a flat section. The bushing is fixed within the pin bore and has a hollow cylindrical body with an outer surface including a cylindrical section and a flat section. The cylindrical section of the bushing engages the cylindrical section of the pin bore. The flat section of the bushing engages the flat section of the pin bore.

Abstract: A piston has a piston crown, a piston pin support that extends from the piston crown, and a skirt wall that is connected to the piston crown. The skirt wall has two tubular pieces which are concentrically arranged relative to each other and each of which is connected to the piston crown in the circumferential region of the piston crown. A hollow space cavity is formed between the tubular pieces and a coolant is disposed in the cavity.

Abstract: Steel pistons used in many internal combustion engines are generally composed of a skirt and a crown. The skirt's function is to reduce the lateral and rotational movement of the piston in the cylinder while the engine is in operation. Lateral and rotational frictional forces imparted to a piston during engine operation cause the piston to scrape off the lubricating oil film present on the cylinder wall. The reduced oil film thickness increases piston and cylinder wall wear due to metal to metal contact. The subsequent metal to metal contact produces a phenomenon called scuffing. This disclosure incorporates several design modifications to the piston and results in a significant reduction of the lateral and rotational motion of the piston during engine operation. The reduction of piston motion reduces the amount of oil film removed from the cylinder wall and increases lubrication efficiency. The Increased lubrication efficiency realized reduces frictional wear power loss and scuffing.

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: An internal combustion engine piston includes a piston crown, a thrust-side skirt, an anti-thrust-side skirt, a first apron, and a second apron. The first and second aprons are connected to the thrust-side and anti-thrust-side skirts through connecting sections. Each connecting section has a thickness that gradually increases as followed from a proximal longitudinal end to a distal longitudinal end, wherein the proximal longitudinal end is closer to the piston crown, and the distal longitudinal end is closer to a distal longitudinal end of a corresponding one of the thrust-side and anti-thrust-side skirts.

Abstract: A piston may include a piston crown including radially inner and outer crown mating surfaces, the crown defining at least in part a cooling gallery extending about a periphery of the crown. The piston may include a piston skirt including a pair of oppositely disposed pin bosses, the pin bosses each defining a piston pin bore. The piston skirt may have a radially inner skirt mating surface cooperating along a radially inner interface region with the radially inner crown mating surface, and a radially outer skirt mating surface cooperating along a radially outer interface region with the radially outer crown mating surface such that the cooling gallery is substantially enclosed. The piston may include at least one cooling fin extending from an interior surface of the cooling gallery.

Abstract: A piston includes a piston head, a ring zone and a piston skirt having load-bearing skirt wall sections and rear connecting walls which interconnect the skirt wall sections and piston-pin bosses which run on a boss axis that is set back from a piston axis and penetrate the connecting walls. The peripheral lower edge of the connecting walls is convex in relation to an axis and the upper edge of said connecting walls, preferably below the ring zone, is concave in relation to an axis perpendicular to a piston-pin axis. The piston is equipped with a reinforced section in the vicinity of the piston head running radially behind the ring zone.

Abstract: Pistons and methods of making the same are disclosed. An exemplary piston assembly may include a piston crown and skirt. The crown may include a crown collar wall extending downward toward a free end of the crown collar wall. The skirt may include a pair of oppositely disposed pin bosses that each define piston pin bores configured to receive a piston pin for securing a connecting rod between the pin bosses. The skirt may further include a radially inner skirt mating surface abutted along a radially inner interface region with the radially inner crown mating surface, and a radially outer skirt mating surface abutted along a radially outer interface region with the radially outer crown mating surface such that a cooling gallery is substantially enclosed. The skirt may further include an inner collar wall extending upwards to the free end of the crown collar wall.

Abstract: Exemplary power cell assemblies and methods of making the same are disclosed. An exemplary power cell assembly may include a piston crown and connecting rod. In an exemplary illustration, a power cell assembly includes a piston crown having a ringland extending circumferentially about a combustion bowl. The boss portions may each include inwardly extending shoulders defining arcuate crown running surfaces. The power cell assembly may further include a connecting rod having a shank and an upper end received in a cavity of the crown. The upper end of the connecting rod may define arcuate connecting rod running surfaces extending away from the shank. The crown running surfaces and connecting rod running surfaces generally allow the connecting rod to pivot with respect to the piston crown about an axis of rotation that extends from one of the boss portions to the other of the boss portions.

Abstract: A method and a manufacturing line allow for the manufacture of piston blanks of dimensions close to the final dimensions, which in the course of subsequent finish-machining need only be machined with removal of material to a small degree. A piston shaft of the piston blank is produced by backward extrusion. At least one hollow throat element is already produced at the piston blank by an upset-forging operation. For this purpose, a special forging tool is provided, which, after the manufacture of the piston shaft, takes effect on the piston blank in such a way that at least one hollow throat element is formed at the latest at subsequent forming of the piston base. In this way, a perceptible reduction is achieved in the weight of a piston in relation to conventionally manufactured forging pistons.

Abstract: A piston ring for sealing a cylinder wall to a piston body is provided. The piston ring includes a ring body of an elastically deformable material which extends substantially circumferentially around an axis and has an inner face that faces the axis. The inner face includes a plurality of axially spaced and radially inwardly extending contact features. The ring body configured to bias the contact features into engagement with the piston body to establish a seal therebetween. At least one of the contact features extends substantially continuously around a circumference for establishing a substantially continuous seal around the piston body, and at least one of the contact features is non-continuous and has at least one recessed area for allowing the passage of oil and gas therethrough.

Abstract: A piston assembly including a piston body and a piston ring is provided. The piston body has a skirt, a portion of which extends circumferentially continuously and has a skirt diameter. The piston ring has a ring body which extends through at least one revolution in a generally helical shape when in a relaxed condition. The ring body also has an inner face, and when in the relaxed condition, the inner face presents a ring diameter which is less than the skirt diameter. The ring body circumferentially surrounds the skirt of the piston body, thereby causing the inner face to be biased into engagement with the outer surface of the circumferentially continuous portion of the skirt of the piston body to establish a dynamic seal between the ring body and the piston body.

Abstract: A piston ring for sealing a cylinder wall to a piston body is provided. The piston ring includes a ring body that extends about an axis and has inner and outer faces. The inner face presents a pair of ridges that extend in a radially inward direction, and the outer face presents a groove. A spring of an elastomeric material substantially circumferentially surrounds the ring body and is seated in the groove on the inner face. The spring biases the ring body in the radially inward direction to seal the ridges against the piston body. The ring body also has at least one oil drainage port which extends at an angle relative to the radially inward direction from the inner face to a location on the outer face on one axial side of the spring for conveying oil out of a space between the ridges.

Abstract: A power cylinder assembly for an internal combustion engine is provided. The power cylinder assembly includes a cylinder wall having a channel formed therein and a piston body with a skirt. A piston ring is seated within the channel of the cylinder wall and is sealed against the skirt of the piston body. Specifically, the piston ring has a ring body with an inner face that presents two radially inwardly extending ridges spaced axially from one another by a valley region, and the outer face presents a groove which receives a spring to bias the ridges into sliding engagement with the outer surface of the skirt of the piston body. The ring body also has at least one oil drainage port which extends radially between the valley region of the inner surface and the groove of the outer face for conveying oil from between the ridges into the groove.

Abstract: A sanitary piston head with a body, said piston head having a fluid-contact end and a drive end and comprising a resilient sealing skirt arranged to provide sealing abutment against the inner wall of a cylinder when said piston head is inserted in said cylinder, wherein the resilient sealing skirt is biased in the sealing direction by a radially biasing element.

Abstract: A piston of an internal combustion engine has a piston crown with annular grooves and a shaft part disposed on the piston crown. The shaft part has bearing shaft wall sections which are connected to one another via inclined connecting walls which are retracted with respect to the outer diameter of the piston. Piston-pin bosses for accommodating a piston pin are disposed in connecting walls. The connecting walls are retracted at such an angle that, in progressing from the lower edge over an intermediate region which lies further back than the lower edge, into an end region which lies further back than the intermediate region the connecting walls to over flush into a hub supporting region below the piston crown.

Abstract: A piston device for internal combustion engines includes a first compression ring and a second compression ring in an outer circumference of a piston, wherein the second compression ring includes a notch extending from the inner circumference to the outer circumference on a lower surface of at least one of a pair of ends of the ring, and a gap between the ring ends at the notch on the second compression ring is larger than a gap between the ring ends of the first compression ring, and a gap between the ring ends at the section other than the notch on the second compression ring is the same or smaller than the gap between the ring ends of the first compression ring, and the second compression ring contains an outer circumferential surface comprised of a tapered surface decreasing the ring radial thickness towards the upper side, and an axial parallel surface formed below the tapered surface.

Abstract: A piston (20) includes a piston skirt (30) extending along a longitudinal axis (L) and having a pair of convex outer surfaces (42) facing opposite one another. Each of the outer surfaces (42) include an oil reservoir (44) above the pin bore axis (P) and an oil recess (46) below the pin bore axis (P) and spaced from the oil reservoir (44) by an intervening oil spreading area (48). The oil reservoir (44) and oil recess (46) each include a bottom (50) extending over an area of the outer surface (42) and surrounded by ramped side walls (52). The oil recess (46) and oil reservoir (44) include radiused corners (54) at a transition between the outer surface (42) and at the bottoms (50), so that the oil reservoir (44), oil recess (46), and outer surface (42) are free of sharp edges.

Abstract: A two stroke engine of a particular configuration can have its power output increased by running bigger pistons and using ports in the piston skirt through which to conduct compressed air within the skirt through short passages in the cylinder housing that conduct the air from within the skirt to above the piston. As a result a larger piston can be used for the same spacing and opening size in the block to save the need to redesign the block and the crankshaft. A position adjuster for the piston moves it axially without rotation of the piston ports out of alignment with inlet ports in the housing. The piston rod is held in the crosshead using a flat to prevent rotation while an adjuster nut that is turned creates axial movement in the piston rod with a lock nut securing the final piston position.

Abstract: The invention relates to a die casting ring (1) internally fitted with radial teeth (11) to be engaged into matching seats (22) provided on a piston (2). This piston-ring assembly prevents mutual rotation or axial translation, in addition to ensuring an optimal seal against infiltration of liquid metal during the die casting process. When the ring has a cutout (10), it can be mounted accurately onto the piston because the teeth (11) allow the cutout to be positioned anywhere relative to the piston.

Abstract: A piston has an upper crown portion with an upper combustion wall against which combustion forces act and a lower crown portion with a pair of pin bosses spaced for receipt of a small end of a connecting rod therebetween. The upper crown portion and the lower crown portion form an outer oil gallery and a central oil gallery in fluid communication with one another. The central oil gallery is formed in part by an annular flange extending radially inwardly from the outer oil gallery and upwardly toward the upper combustion wall to a free edge spaced from the upper combustion wall. The free edge forms an opening about a central axis of the piston and has a non-planar uppermost surface with depressions aligned diametrically opposite one another across the opening to improve the oil flow throughout the central oil gallery.

Abstract: The invention relates to a method for producing a piston for a combustion engine comprising a combustion recess, during which an annular fiber preform for reinforcing the edge of the combustion recess is firstly fastened inside the casting mold. Afterwards, a low-silicon aluminum/copper melt is introduced into the casting mold by which the fiber preform is infiltrated and molded into the recess edge within the scope of the casting process. The piston blank produced in this manner is then subsequently compacted by a high-temperature isostatic pressing before the piston is completed by means of a machining completion process. The flanks and the base areas of the second and third annular groove are coated by means of anodic oxidation, and the hub boreholes are smoothed and hardened by roller-burnishing. This results in a very high-quality and heavy-duty piston.

Abstract: A piston assembly is disclosed herein. The piston assembly is integrally formed and unitary and is centered on a central longitudinal axis. The piston assembly includes a head with ring belt having a plurality of ring grooves. The piston assembly also includes first and second skirts, each having a top edge and a bottom edge being radially narrower than the top edge. The skirts also include first and second side edges. The piston assembly also includes first and second pin bosses spaced radially inward from the ring belt to define a short-pin support arrangement. The pin bosses include respective first and second pin bores axially aligned on a pin bore axis perpendicular to the central longitudinal axis. The piston assembly also includes a plurality of panels, each extending between one of the pin bosses and one of the skirts.

Abstract: A piston for an internal combustion engine is provided. The piston crown includes an interior surface that defines at least in part a cooling gallery and a cooling gallery surface within the piston. An annular surface may defines at least in part an annular passageway that allows fluid communication between an outer surface of the piston and the cooling gallery. Opposing annular surfaces may be abutted with a predetermined force, thereby limiting fluid flow from the cooling gallery to an outer surface of the piston. Further, an annular surface may extend into the cooling gallery to form a deflector along the cooling gallery surface, thereby limiting fluid flow from the cooling gallery to an outer surface of the piston.

Abstract: A piston of an internal combustion engine has a piston crown with annular grooves and a shaft part disposed on the piston crown. The shaft part has bearing shaft wall sections which are connected to one another via inclined connecting walls which are retracted with respect to the outer diameter of the piston. Piston-pin bosses for accommodating a piston pin are disposed in connecting walls. The connecting walls are retracted at such an angle that, in progressing from the lower edge over an intermediate region which lies further back than the lower edge, into an end region which lies further back than the intermediate region the connecting walls to over flush into a hub supporting region below the piston crown.

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 piston allowing a lubrication layer of a resin coating with a low friction coefficient to be tightly adhered to a skirt portion of a piston for an internal combustion engine, with low friction, superior wear resistance, and superior anti-seizing properties and that can reduce wear of a cylinder inner wall even if the lubrication layer is peeled off or abraded, is provided. Metal or ceramic fine particles having an average particle diameter of 20 ?m to 400 ?m are injected with compressed air or compressed nitrogen as a mixture fluid onto the skirt portion of the piston, made of an aluminum alloy and produced by a method such as casting or forging, at an injection speed of 80 m/s or more or an injection pressure of 0.2 MPa or more to be collided with the skirt portion, thereby uniformly making a microstructure of a piston base material fine-grained in a depth range of 1 ?m to 15 ?m from a surface of the skirt portion and forming a modified layer with an activated surface.

Abstract: A piston (20) includes a piston skirt (30) extending along a longitudinal axis (L) and having a pair of convex outer surfaces (42) facing opposite one another. Each of the outer surfaces (42) include an oil reservoir (44) above the pin bore axis (P) and an oil recess (46) below the pin bore axis (P) and spaced from the oil reservoir (44) by an intervening oil spreading area (48). The oil reservoir (44) and oil recess (46) each include a bottom (50) extending over an area of the outer surface (42) and surrounded by ramped side walls (52). The oil recess (46) and oil reservoir (44) include radiused corners (54) at a transition between the outer surface (42) and at the bottoms (50), so that the oil reservoir (44), oil recess (46), and outer surface (42) are free of sharp edges.

Abstract: A piston cooling apparatus of an engine may include a combustion chamber formed between a piston disposed in a cylinder block and a cylinder head disposed on the cylinder block, wherein a surface area-enlarging portion is formed inside the piston on bottom surface of a crown of the piston.

Abstract: A piston holder for a vehicle sensor including a diaphragm deflectable under fluid pressure to move a piston includes a unitary body that in turn defines a cylindrical outer body portion configured for surrounding the piston. The body has an open upper end circumscribed by an outwardly-flared flange and a rounded annular elbow opposite the flange for contacting the diaphragm. An annular skirt extends from the elbow. The skirt includes a first portion oriented radially inwardly and upwardly at an oblique angle to the vertical dimension defined by the outer body portion. An inner bump is formed in the first portion for establishing a contact point with the diaphragm when the holder is deformed, and a second portion extends from the first portion and is oriented parallel to the axial dimension for engaging a channel of the piston.

Abstract: The present invention utilizes rolling elements, such as balls or rollers acting as bearings carried in openings in the skirt or equivalent portion of a piston, to engage the cylinder walls and replace the sliding bearings of the skirt with the roller elements in the skirt. The rolling elements then absorb all or some of the thrust loads conventionally absorbed by the skirt walls sliding along surfaces of an associated cylinder and thereby reduce the friction forces developed by the reciprocating action of the piston skirt.

Abstract: By forging a metal material, there is formed a dustproof boot 20 in which a side of an opening end portion 20b formed with a groove 34 for a dustproof boot is provided with a diameter smaller than that of a side of a piston main body 20a, and a total thereof is provided with a substantially uniform wall thickness, thereafter, by carrying out ironing from a front end of the opening end portion 20b to the piston main body side, the recess groove 34 for the dustproof boot can be formed by providing a build-up portion 20c at the opening end portion.

Abstract: A two-part piston for an internal combustion engine has an upper part that has a pin having an outside thread on the underside of its piston crown, and has a lower part that has a crown part, onto which an expansion sleeve that can stretch elastically in the axial direction is formed, radially on the inside. A pin is introduced into the sleeve in order to screw the upper part to the lower part. The expansion sleeve is stretched in the axial direction. In order to improve its strength, the material of the expansion sleeve has a higher stretching limit as compared with the rest of the piston material. The increase in the stretching limit is achieved by permanent stretching of the expansion sleeve in the axial direction, by approximately 1% of its length.

Abstract: A piston extends along a central axis with an upper crown and a boss depending from the crown. The boss has opposite sides extending along opposite sides of the central axis to a free end and an annular pocket extending laterally into at least one of the sides. The boss further includes an opening extending through the free end into the pocket. The opening has a width extending from the side in which the pocket extends toward the other side of the boss. An assembly including the piston further includes a connecting rod terminating at a small end configured for receipt in the pocket with a shank extending from the small end. The small end can be provided with an external bearing material on a convex outer surface, and the small end is unobstructed from lateral movement along the opening over a full stroke of the piston.

Abstract: A number of embodiments of a piston may have a shape that provides enhanced piston guidance. In such embodiments, the piston shape may include an axial profile that is configured to provide certain thrust load characteristics.

Abstract: A number of embodiments of a piston may have a shape that provides enhanced piston guidance. In such embodiments, the piston shape may include an axial profile that is configured to provide certain thrust load characteristics.

Abstract: An axial piston motor, particularly an air-conditioning compressor for motor vehicles, including at least one piston with an essentially cylindrical piston skirt and with a wrap-around element, which wraps around a swivel ring or a swash plate and a piston slipper that slides on this swivel ring or this swash plate.

Abstract: A compressor which includes a piston (150) reciprocating in a cylinder bore (111) provided in a cylinder block. Length of the circumferential surface at the compression load side (160) is made to be longer than that at the anti-compression load side (170), so that area of sliding-contact surface at the compression load side is greater than that at the anti-compression load side. The above configuration is effective to prevent occurrence of wearing due to unsymmetrical contact of piston with cylinder bore. Thus, deterioration in the refrigeration capability and instability of the performance is prevented.

Abstract: A piston includes a crown portion generally defining an axis and having a skirt connecting portion. The skirt connecting portion is defined, at least in part, by a first crown mating portion, a second crown mating portion positioned radially from the first crown mating portion, and a crown chamber surface extending between the first crown mating portion and the second crown mating portion. The piston also includes a skirt having a crown connecting portion. The crown connecting portion is defined, at least in part, by a first skirt mating portion, a second skirt mating portion, and a skirt chamber surface extending between the first skirt mating portion and the second skirt mating portion. The first crown mating portion is selectively coupled to the first skirt mating portion. The second crown mating portion is selectively coupled to the second skirt mating portion to define a piston chamber that is defined, at least in part, by the crown chamber surface and the skirt chamber surface.