Abstract: Methods and systems are provided for a surface structure for a piston. In one example, the surface structure is located on at least a portion of the piston.

Abstract: Disclosed is an internal combustion engine's piston with a piston head having first and second thinnest portions that are thinnest in thickness of the piston head. With respect to the center axis of the first and second pin holes for supporting the piston pin, the first and second thinnest portions of the piston head are respectively provided on both sides of a transverse axis that is perpendicular to the center axis of the first and second pin holes. Each of first and second rib portions that are respectively formed on inner surfaces of first and second pin boss portions extends at the piston head in a direction along the transverse axis to overlap each of the first and second thinnest portions of the piston head. This piston is capable of relaxing stress concentration at a position above the piston pin.

Abstract: A piston for an internal combustion engine has a crown, a skirt extending from the crown, a pair of pin bosses, and a plurality of struts connecting the pin bosses to inner sides of the crown and skirt. An internal combustion engine having the piston is also disclosed.

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 for an internal combustion engine has a piston crown, a circumferential fire land, a circumferential ring part having annular grooves, and a piston skirt, which comprises two skirt walls and two box walls set back from the ring part and connecting the skirt walls in such a way that an exposed underside of the ring part is formed in the area of each of the box walls. The box walls are provided with pin bosses having pin bores. At least one support element is arranged between each exposed underside of the ring part and the box wall associated with the underside of the ring part.

Abstract: A piston with transverse-rib through holes formed easily therein for reducing the cost of manufacturing. A piston includes a pair of mutually opposed longitudinal ribs individually formed with piston pin bosses interconnecting a pair of piston skirt portions on a back side of a piston head. A pair of transverse ribs interconnect the mutually opposed longitudinal ribs with the transverse ribs. The pair of transverse ribs are formed with transverse-rib through holes at places proximal to the back side of the piston head. A skirt opening is formed by cutting away a part of the piston skirt portion that is opposed to the transverse rib and faces the transverse-rib through hole.

Abstract: A drive mechanism for a hammer drill comprises a hollow piston 558 having a cylindrical bearing that is adapted to receive a crank pin in order to cause the hollow piston 558 to reciprocate inside a spindle 548. A plurality of longitudinal ridges 559 are formed on the outer surface of the hollow piston 558 to reduce the surface area of contact between the hollow piston 558 and the spindle 548, and a plurality of grooves 561 are formed in the gaps between the ridges. The grooves 561 are adapted to retain lubricant 563 in order to reduce frictional contact between the hollow piston 558 and the spindle 548.

Abstract: According to one embodiment, there is provide a piston pump, including: a cylinder having a bottomed cylindrical shape; a piston slidable within the cylinder, the cylinder and the piston defining a pressure chamber therebetween; a suction valve unit disposed in a suction passage of the pressure chamber; and a discharge valve unit disposed in a discharge passage of the pressure chamber, wherein the piston includes a cylindrical piston portion and a large diameter piston portion provided to cover one end of the cylindrical piston portion, and wherein the large diameter piston portion includes a working fluid guide groove extending thereinside along the axial direction of the piston.

Abstract: A piston with transverse-rib through holes formed easily therein for reducing the cost of manufacturing. A piston includes a pair of mutually opposed longitudinal ribs individually formed with piston pin bosses interconnecting a pair of piston skirt portions on a back side of a piston head. A pair of transverse ribs interconnect the mutually opposed longitudinal ribs with the transverse ribs. The pair of transverse ribs are formed with transverse-rib through holes at places proximal to the back side of the piston head. A skirt opening is formed by cutting away a part of the piston skirt portion that is opposed to the transverse rib and faces the transverse-rib through hole.

Abstract: The invention relates to a piston (10, 110, 210, 310) for an internal combustion engine, comprising a piston head (11, 111, 211, 311) and a piston shaft (16, 116, 216, 316). The invention is characterized in that on the internal wall (22, 122, 222, 322) of the piston shaft (16, 116, 216, 316) at least one reinforcing rib (25, 125, 225, 325) is provided that extends in parallel to the piston center axis (A).

Abstract: A reciprocating compressor is provided that includes a compression chamber inside of a cylinder and a piston inserted therein. The piston includes a head, a skirt extended from a lower end of the head so as to be spaced away from an inside wall of the cylinder, and guide surfaces extended from an outside surface of the skirt. Since the skirt is not in contact with the cylinder, a friction loss between the piston and the cylinder is reduced, and the guide surfaces assist the piston to make stable reciprocation. The head has a projection so as to be inserted into a discharge hole when the piston is at a top dead center. According to this, a dead volume formed when the piston is at the top dead center is reduced, thereby improving an efficiency of the compressor.

Abstract: A piston for a two-cycle engine having a piston head and a piston wall in which are disposed wrist pin eyes. At least one undercut is formed between the underside of the piston head and the wrist pin eyes at a distance from the piston head. The undercut extends from the interior of the piston toward the piston wall. A respective thickened portion is provided in at least one region of the piston that is rotationally shifted about the longitudinal axis of the piston by 90° relative to one of the wrist pin eyes. The thickened portion is disposed at a distance below the piston head and extends into the interior 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 monobloc piston assembly has at least two parts fixedly joined together forming a piston body having an oil cooling gallery. The oil cooling gallery is defined by an upper wall, a lower wall, and a pair of radially spaced inner and outer annular walls. A skirt is formed as one piece and of the same material with at least one of the two parts and depends generally along a longitudinal axis from the lower wall. A pair of pin bosses are spaced laterally from the longitudinal axis and depend generally from the lower wall. At least one elongated opening extends generally between the pin bosses with the opening preferably spanning a substantial portion of the distance between the pin bosses. Oil flows into and out of an oil cooling gallery through the opening.

Abstract: A monobloc piston assembly has at least two parts fixedly joined together forming a piston body having an oil cooling gallery. The oil cooling gallery is defined by an upper wall, a lower wall, and a pair of radially spaced inner and outer annular walls. A skirt is formed as one piece and of the same material with at least one of the two parts and depends generally along a longitudinal axis from the lower wall. A pair of pin bosses are spaced laterally from the longitudinal axis and depend generally from the lower wall. At least one elongated opening extends generally between the pin bosses with the opening preferably spanning a substantial portion of the distance between the pin bosses. Oil flows into and out of an oil cooling gallery through the opening.

Abstract: Pistons for internal combustion engines often need additional cooling to attain better performance. One method of cooling involves adding oil to an oil gallery opposite a combustion zone. Adding a standpipe prevents a preestablished quantity of oil from exiting the oil gallery. Installing the standpipe intermediate a first baffle plate and a second baffle plate improves reliability of the piston and ease of manufacturing.

Abstract: The present invention, being a continuation-in-part of the Reinforced Wrist-pin, makes use of a traversing reinforcing matrix for the non-mechanical surfaces of the piston and connecting-rod components' assembly. Interposing holes, or spacial impressions, within the non-contacting surface planes of such components with reinforcing members formed within such holes, for providing supplemental structural strength, as the multitude of these holes reduce overall component weight for improved efficiency of mechanical operation. For a certain configuration of the surfaces the spacial impressions are through-pass openings within the component. For another configured condition, they only recede a certain distance. Also, a specific surface condition has vertical and horizontal reinforcement members, as another condition only has horizontal members. Cumulatively, these reinforced holes provide effective weight reduction for the force transmitting assembly without compromising structural strength.

Abstract: In a reciprocating piston of an internal combustion engine comprising a piston skirt having a major-thrust-side skirt portion and a minor-thrust-side skirt portion, a projected circumferential width of the minor-thrust-side skirt portion is greater than a projected circumferential width of the major-thrust-side skirt portion. Additionally, the piston skirt is dimensioned so that the minimum thickness of the minor-thrust-side skirt portion is less than the minimum thickness of the major-thrust-side skirt portion.

Abstract: A piston for an internal-combustion engine has two webs respectively between the piston shaft and the pin eyes displaced toward the inside thereof. In order to achieve sufficient stability and rigidity, as well as a low-wear moldability one of the webs between the pin eye and the shaft wall is displaced toward the outside. Misarrangement also provides good accessibility for splash oil cooling.

Abstract: A piston skirt has narrowed relief sections adjacent piston bosses and between first and second relief sections. The first relief sections extend between a piston head and respective piston bosses whist the second relief sections extend downward from the respective piston bosses. The narrowed relief sections are spaced from each other in parallel to piston pin holes at a distance which is smaller than that at which the first and second relief sections are space from each other, respectively. The narrowed relief sections are formed thicker and therefore more rigid than the first and second relief sections so that the piston skirt is more rigid adjacent the piston bosses and less rigid above and below the piston bosses, whereby to effectively lessen side thrust of the piston to the cylinder wall without deteriorating the durability.

Abstract: The design and construction of past piston assemblies having a wrist pin bolted to a connecting rod have excessive weight and structural components, and requires more complex machining techniques and tooling. The present invention overcomes these problem by providing a piston assembly (30) with a wrist pin (36) attached to a piston member (32). Thus, the length of the leg members (80) are short and do not require a portion surrounding the wrist pin (36). The results being reduced piston member (32) and piston assembly (30) weight and lower inertia, a simplified forging or casting process, a more easily machinable cavity (86) within the piston member (32) and a higher quality piston assembly (30).

Abstract: A piston for an internal combustion engine is provided. This piston includes a piston body which has an upper ring land portion and a skirt portion, pin boss portions formed in the skirt portion into which a piston pin is inserted for attaching the piston body to a connecting rod, and a rib portion projecting from an inner wall of the skirt portion. The rib portion extends from the first areas which include cross points where the centerline, perpendicularly passing the longitudinal axis of the pin boss, intersects the inner wall of the piston skirt to the second areas which include the bottoms of the pin boss portions.

Abstract: A piston is longitudinally slidable within a pressurized container to dispense materials from the container. The piston has a generally annular sidewall and a traverse barrier wall at one end of the sidewall and integral therewith to define a cup-shaped closure open at one end. An annular step is provided on the sidewall which divides the sidewall into two segments, an upper segment and a lower segment. The annular step is below and spaced from the barrier wall. The upper segment has a diameter smaller than the diameter of the lower segment and the clearance between the upper segment and the interior of the container is substantially greater than the clearance between the lower segment and the interior of the container.

Abstract: In order to achieve less deformation under gas pressure load and also under thermal load, the bottom piece of a piston with ring-carrying barrel is configured as a supporting cone tapering towards the piston pin and connected with the piston pin bosses by means of supporting elements. Cone, bosses and supporting elements are made in one piece. The supporting elements comprise walls extending essentially parallel to the axis of the piston pin. First distance (A) to the outer perimeter of the piston in the direction of the piston pin axis (Y--Y) are greater than the corresponding second distances (B) normal to this axis. The end parts of the walls are curved inwardly and leave open an area around an axis (X--X) normal to the piston pin axis.

Abstract: Present day diesel engines having aluminum piston assemblies are limited to combustion chamber pressures of approximately 12,410 kPa (1,800 psi) whereas the desire is to increase such pressures up to the 15,170 kPa (2,200 psi) range. To reach such levels the instant piston assembly includes a steel piston member having an upper cylindrical portion defining a top surface, a depending tubular wall and an annular cooling recess having one or more machined surfaces of revolution about a central axis. The cooling recess is located beneath the top surface and juxtaposed to the top ring groove for removing heat away therefrom in use. The piston member is preferably forged and subsequently machined to precisely controllable dimensions. Moreover, the piston assembly is preferably of the articulated type and includes a forged aluminum piston skirt connected to the piston member through a common wrist pin.

Abstract: A two-part, low compression height, open-ended hollow skirt-type piston for internal combustion engines has a piston pin creating an articulated connection of the separate skirt and head parts. Guide portions (5) protruding axially in the direction of the piston axis provide lateral guidance and support of the piston head (1) in the piston-pin-axis direction. Each of the guide portions forms a gap with the nearby gudgeon pin boss (3). The gaps receive opposite parallel flat surfaces (4) of the skirt (2). The overhanging guide portions (5) have partly circular recesses permitting assembly of head and skirt with the gudgeon pin.

Abstract: A spherically-shaped piston is rigidly attached to a connecting rod for reciprocating and tilting motion within a borehole in response to rotation of a crankshaft having an associated crank which is rotatably attached to the connecting rod. Web and ribs and ridges integrally formed on the hollow, underside of the piston control thermal transfer and deformation to assure continuous perimeter seal with the walls of the borehole over all operating temperatures as the piston sides and tilts within the borehole.

Abstract: Pistons are described having improved stiffness of the lower skirt regions to improve piston guidance and oil film distribution. The pistons comprise a crown portion including piston ring grooves and a skirt portion, the skirt portion being divided into an upper skirt region and a lower skirt region and wherein on each side of the plane including the piston axis and the gudgeon in axis the support skirt region includes at least one bearing surface and the lower skirt region comprises a bearing surface supported by two substantially planar skirt wall sections lying in planes forming an acute angle of less than 75.degree. with the plane which includes the piston and gudgeon pin axes, the maximum bearing contact arc of the lower skirt bearing surface lying between 10.degree. and 22.5.degree. either side of the lane which is normal to the gudgeon pin axis and which includes the piston axis.

Abstract: A piston for an internal combustion engine including a crown, a skirt and bosses. The skirt has a circumferentially extending faucet rib in a lower portion of the skirt and reinforcing ribs which extend in a thrust and thrust-opposing direction of the piston from the bosses straight to the faucet rib. Reinforcing ribs increase the rigidity of piston in the thrust and thrust-opposing direction and suppress parmanent deformation of the skirt in the thrust and thrust-opposing direction, resulting in decreasing slapping sounds in a piston and cylinder structure without sticking of a piston with a cylinder bore.

Abstract: A composite piston for use in the cylinder of a diesel engine has coaxial first and second sections and a piston pin which articulately connects the sections to each other and to the piston pin bushing of the connecting rod. The first section has a round head and two piston pin bosses which are connected to the head by a hollow frustoconical portion of the first section. The bosses are reinforced by two walls each of which is integral with each boss. The walls are mirror symmetrical to each other with reference to a plane which includes the axes of the piston pin and of the composite piston. The inner sides of the walls are cooled by sprays or streams of a liquid coolant which flows through apertures provided in the walls close to the frustoconical connecting portion and serving to permit the coolant to thereupon flow along the outer sides of the respective walls.

Abstract: A spherically-shaped piston is rigidly attached to a connecting rod for reciprocating and tilting motion within a borehole in response to rotation of a crankshaft having an associated crank which is rotatably attached to the connecting rod. Web and ribs and ridges integrally formed on the hollow, undeside of the piston control thermal transfer and deformation to assure continuous perimeter seal with the walls of the borehole over all operating temperatures as the piston sides and tilts within the borehole.

Abstract: A method is disclosed of manufacturing a piston having a skirt on which are formed a plurality of bearing surfaces, each bearing surface being at a predetermined axial position on the skirt, being spaced outwardly of the skirt to a required radial dimension and extending around the skirt with a required circumferential dimension. The method comprises forming the bearing surfaces in at least two stages. First a plurality of projections are formed on a skirt of the piston with each projection being at an axial position in which a bearing surface or surfaces are to be located. The radial and/or axial dimension of the projection exceeds the required corresponding dimension or dimensions of the bearing surfaces. A second step then forms bearing surfaces of the required dimensions. A second form of piston is formed with cylindrical portions which are alternately offset to one side or other of the piston axis to form, one each side of the piston, alternate projecting bearing surfaces and recessed skirt portions.

Abstract: A piston made of cast aluminum base alloy is provided with gudgeon pin bosses which are connected to the piston skirt by means of a frusto-conical strut which has recesses in the skirt and are specially dimensioned to leave large unsupported skirt areas to minimize risk of seizure in an engine cylinder; in particular the distance between the outer surfaces of the bosses is from 0.6 to 0.8 of the outer diameter of the piston and the distance between the inner surfaces of the bosses is 25 to 35 percent of the outer diameter of the piston, and the cone angle of the struts is from 60.degree. to 110.degree..

Abstract: A piston for an internal combustion engine is provided with two separate skirt portions on either side of the gudgeon pin bore. Each skirt portion is the shape of a sector of a cylinder and is cantilevered on a pair of struts connected to the skirt members at points intermediate their top and bottom edges. The skirt members have top and bottom bearing surfaces which provide the running surfaces against the associated cylinder or liner and which are connected to the centers of the skirt members by flexible flanges. This allows these running portions to flex and absorb substantial lateral loads without creating noise so that the piston is quiet as well as being lightweight.

Abstract: An injection-molded piston for an aerosol container has a face portion for contacting and exerting pressure on material to be dispensed, and a thin, flexible skirt depending axially from and circumscribing the face portion for forming an effective seal against the inside wall of the container. The outer wall of the skirt is continuous, while the circumference of the inner wall has alternating areas of constant thickness along said areas and areas of minimum thickness, the curved portions forming with the outer wall a plurality of sections, the thickness and circumferential extent of each of which decrease axially along the skirt toward its distal end. The piston includes a depending extension on the skirt which aids sealing.

Abstract: A piston comprises a crown (10) and a ring band (11) carried on two gudgeon pin bosses (12a, 12b) by two supports (20). There are upper and lower pairs of struts (21a, 21b, 21c, 21d) on each side of the gudgeon pin bosses, one strut of each pair projecting from one gudgeon pin boss and the other strut of each pair projecting from the other gudgeon pin boss. Each pair carries a respective arcuate skirt portion (22) which extends only part the way round the and is symmetrical about a plane including the piston axis (28) and normal to the gudgeon pin bore axis. There are thus axially and circumferentially extending gaps (25) of constant axial width both between the upper arcuate skirt portions and the ring band between the upper arcuate skirt portions and the lower arcuate skirt portions. This provides a lightweight piston which is very conformable and can be fitted tightly in an associated cylinder or liner to reduce noise.

Abstract: A light alloy piston for internal combustion engines has a skirt which is closed at its lower end and at locations disposed adjacent to the bosses on both sides of the horizontal plane through the piston pin is set back so as to form respective recesses. In order to avoid a retention of oil in the recesses those end portions of the skirt which adjoin the recesses are inwardly offset from the outside peripheral surface of the piston.

Abstract: A piston for an internal combustion engine has the conventional skirt replaced by top and bottom bearing surfaces spaced apart by a substantial gap of constant width. The top bearing surfaces are connected to the piston crown through the ring band whereas the bottom surfaces are attached to piston bosses by struts. The gap allows the passage of lubricant to the cylinder to ensure adequate lubrication of the bearing surfaces.

Abstract: A piston (2) is of refractory materials, particularly for a compression-ignition engine of the type having a head (4), a skirt (6) and their mutual fastening means. According to the invention, this skirt (6) is formed entirely of a refractory material and has two semicylindrical parts (18, 20) each of which has ribs (22) and a semispherical cavity (36, 38). After assembly, the cavities form a ball joint seat for the small end of a piston rod along a plane containing the longitudinal axis (14) of the piston (2). Application is to compression-ignition engines with high efficiency.

Abstract: An actuator (10) tolerant of ballistic damage thereto includes a piston (25) longitudinally reciprocable within a cylinder (15) and connected to a rod (30), the piston comprising a plurality of longitudinally stiff, circumferentially spaced ribs (35) joined by a bulkhead (40) which transfers hydraulic loading to the ribs and readily ruptures in response to impact with an obstruction (45) in the cylinder wall due to for example, ballistic damage to the actuator. The bulkhead carries a sealing ring (60) for sealing leakage around the piston and may be formed integrally with the ribs or separately therefrom and attached thereto as an end cap to the piston. Analogous structure may be employed in a gland (20) for the actuator to accommodate ballistic damage to the rod.

Abstract: An actuator (10) tolerant of ballistic damage thereto includes a piston (25) longitudinally reciprocable within a cylinder (15) and connected to a rod (30), the piston comprising a plurality of longitudinally stiff, circumferentially spaced ribs (35) joined by a bulkhead (40) which transfers hydraulic loading to the ribs and readily ruptures in response to impact with an obstruction (45) in the cylinder wall due to for example, ballistic damage to the actuator. The bulkhead carries a sealing ring (60) for sealing leakage around the piston and may be formed integrally with the ribs or separately therefrom and attached thereto as an end cap to the piston. Analogous structure may be employed in a gland (20) for the actuator to accommodate ballistic damage to the rod.

Abstract: A piston for an engine or motor has a skirt which includes two portions which are urged towards an associated cylinder during the various strokes of the working cycle. Each portion is provided with a bearing surface or surfaces for sliding engagement with the associated cylinder during reciprocation. The piston is provided with formations which pass lubricant to and over the bearing surfaces.

Abstract: A piston for internal combustion engines, preferably made of aluminum or its alloys, having freely suspended piston pin bosses connected by first ribs to the piston head at points of zero moment and by second ribs to the piston skirt. The piston skirt has apertures in register with the bores in the piston pin bosses. The piston head is separated from the piston skirt by a transverse slot through at least a part of the circumference of the piston head and the ribs which connect the piston pin bosses to the piston skirt extend at an angle of 0.degree.-45.degree. to the boss plane.

Abstract: In a cast light-alloy piston having a skirt which is recessed adjacent to the piston pin bosses, the two sides of the skirt are unsymmetrical with respect to the piston pin bosses.For an improved adaptation to the different conditions of operation of the engine, the skirt is connected to the piston pin bosses on one side by supporting ribs which extend at an angle of 30 to 60 degrees to the piston pin axis, and on the other side by supporting ribs extending at an angle of 90.degree. to the piston pin axis.

Abstract: An improved piston structure for Diesel and like reciprocating piston engines is provided having a top and foot, a sealing section on said piston connecting said top and foot, a guide section articulatedly connected to said sealing section through trunnion means on a connecting rod, said guide section having a sliding shell in the form of a collar at its periphery surrounding a wrist pin in the region of its bearing points, and at least one rib for each bearing side in the form of a chord connected to said shell in the region of the bearing point.

Abstract: A plastic disc brake piston is disclosed with a novel fluted inner core design, giving a piston with superior structural strength, crack resistance, and improved heat dissipation when used in disc brake assemblies.

Abstract: Present day diesel engines having aluminum piston assemblies are limited to combustion chamber pressures of approximately 12,410 kPa (1,800 psi) whereas the desire is to increase such pressures up to the 15,170 kPa (2,200 psi) range. To reach such levels the instant piston assembly includes a steel piston member having an upper cylindrical portion defining a top surface, a depending tubular wall and an annular cooling recess having one or more machined surfaces of revolution about a central axis. The cooling recess is located beneath the top surface and juxtaposed to the top ring groove for removing heat away therefrom in use. The piston member is preferably forged and subsequently machined to precisely controllable dimensions. Moreover, the piston assembly is preferably of the articulated type and includes a forged aluminum piston skirt connected to the piston member through a common wrist pin.