Abstract: A piston for an internal combustion engine may include at least one oil ring groove configured to receive an oil scraper ring. The at least one oil ring groove may have an upper groove flank, a lower groove flank, and a groove base. The at least one oil ring groove may be structured to be asymmetrical and deeper in a radial direction in a region of the lower groove flank. The piston may also include an oil outflow channel structured and arranged to fluidically communicate with an oil collecting chamber disposed in a spine of the oil scraper ring. A connecting point between at least one of (i) the at least one oil ring groove and the oil outflow channel, and (ii) the oil collecting chamber and the oil outflow channel may be disposed exclusively in the lower groove flank.

Abstract: A cylinder coupling structure of a compact air compressor includes a block, a tubular-shaped cylinder assembled to the block, a valve cover which covers the valve assembly, and at least one pressurized bolt which assembles the valve cover and the block. A piston is reciprocated inside the cylinder. A stator is assembled to the block, a rotator is located to relatively rotate as to the stator, and a crank axis is assembled to the rotator to integrally rotate with the rotator to be axially supported in the block and to be rotatable. A connecting rod, each of both ends thereof is connected to the crank axis and the piston, respectively.

Abstract: A seal ring and a sealing structure that reduce the deviation of the central axis of the seal ring from the central axis of a shaft thereby preventing the seal ring from abutting against the tip end of a housing in the operation of inserting the shaft in the housing. The seal ring includes a thin part 100A provided in a range less than 180° with respect to a circumferential direction and a thick part 100B, which is configured to protrude inward in the radial direction from an inner peripheral surface of the thin part 100A, the thin part 100A has an abutment joint part 110, and the thick part 100B has, at respective ends of both side surfaces on an inner peripheral surface side thereof, a concave part 120 over an entire range thereof to form a gap between the ends of the both side surfaces and corner parts at both ends of a groove bottom of the annular groove.

Abstract: In a piston-ported engine, a sealing ring may be placed in a groove in the cylinder. As the groove is of greater diameter than the cylinder, the sealing ring overlaps into a helix allowing it to be enter the cylinder. However, such a helix does not fit into a groove without when in the helix. Alternatively, a shorter sealing ring is placed into the groove. However, the gap is too large. According to one embodiment, a groove of double the width of the ring is provided and the helical ring is installed and caused to unwind in the groove so that the ring sits in a plane. A spacer ring is placed in the groove to fill the extra space in the groove. An elastomeric material or a tension spring in an outer groove in the sealing ring can be used to cause the ring to press against the piston.

Abstract: The invention provides a low tension piston ring having a finished outer diameter and negligible tangential tension. The method includes the steps of machining a stock bar to an initial outer diameter slightly greater than the finished outer diameter of the piston ring, finishing the initial outer diameter of the stock bar to a rounded profile having a nominal diameter equal to the finished outer diameter, and machining the stock bar to the preferred cross-section. Dykes-type piston rings can have keystone or semi-keystone shaped cross-sections. The method continues by detaching the piston ring from the stock bar using a parting tool in response to completing all tension inducing operations including the steps recited above. The method continues with the steps of lapping the piston ring to a final longitudinal thickness and cutting the piston ring longitudinally to form a final gap.

Abstract: A sealing structure permits easy fitting of the insertion member into the reception member and that prevents damage to the insertion member and the reception member. The insertion member includes a first larger-diameter columnar portion, a first smaller-diameter columnar portion, and a first step portion. The reception member includes a second larger-diameter cylindrical portion, a second smaller-diameter cylindrical portion, and a second step portion. An accommodation region for accommodating an O-ring is defined by an outer circumferential surface of the first smaller-diameter columnar portion, an outer surface of the first step portion, an inner circumferential surface of the second larger-diameter cylindrical portion, and an inner surface of the second step portion.

Abstract: A caliper comprising: a piston bore and a seal groove located in the piston bore proximate to an open end of the piston bore, the seal groove comprising: a front wall; a rear wall; a bottom wall spanning between and connecting the front wall to the rear wall; a projection in a central region of the bottom wall suitable for allowing twisting of a seal during a brake retract and/or brake release; wherein the rear wall diverges away from the front wall as the rear wall extends away from the bottom wall and towards the bore surface.

Abstract: The invention relates to an oil scraper ring groove ring arrangement for pistons of internal combustion engines. The inventive arrangement comprises a disk that is provided with parallel flanks and a bearing surface having an asymmetrical crowned form with a vertex line extended over the periphery of the disc, with the disk being arranged in a ring groove of the piston with a ring groove side opposing the piston head and a ring groove side facing the piston head. The aim of the invention is to achieve an improved oil scraping action compared to that of prior art, while reducing the friction and the abrasion in such a way that it is radially outwardly inclined to the outer diameter of the piston, the bearing surface of the disk being embodied in such a way that it corresponds to an almost worn end contour in the started engine state, and, when the oil scraper ring is mounted in the piston, the vertex line of the bearing surface is oriented in the direction of the ring groove side opposing the piston head.

Abstract: The present invention pertains to a wiping and/or sealing element for sealing a piston (11) guided movably in a housing (10) with a seal held in a groove (21, 30). The present invention pertains, furthermore, to a process for sealing a movable piston (11) by means of a seal inserted into a groove (21, 30) and a clamping and/or support element with a piston (21), which is guided in a housing (10) such that it can be withdrawn and extended, wherein the piston (11) is sealed by means of a seal arranged in a groove (21). To achieve sealing of the piston (11) with a high sealing force for high liquid pressures at low friction, the wiping and/or sealing element according to the present invention as well as the clamping and/or support element according to the present invention are wherein the seal is a quad ring (22) with a square cross section.

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

Abstract: A piston assembly having a piston and a piston ring. The ring mates to the piston in a groove on the outer surface of the piston. The ring includes two side walls that connect between inner and outer peripheral walls. The side walls converge outwardly at different angles from the inner peripheral wall to the outer peripheral wall. The angles are different to produce a twist feature of the ring within the piston groove to generate a better seal by the ring. The groove of the piston is generally tapered and has top and bottom walls converging at angles approximately equal to the angles of the side walls of the ring. A method of manufacturing the piston assembly includes forming first and second side walls having first and second angles by outwardly converging from the inner peripheral wall to the outer peripheral wall.

Abstract: A piston and ring assembly for a compressor that may be used in a vehicle air conditioning system. The assembly comprises a piston and a ring located within a cylinder bore. The ring has a frustoconical shape and the piston has a complementary frustoconical groove. The ring is a parallelogram in cross-section.

Abstract: A ring groove for a two-piece oil ring of a piston is provided that has ring body equipped with a coil expander, wherein the ring body has an upper outer surface and a lower outer surface, both orthogonal to the axial direction of the piston. The ring groove also has an upper inner surface and a lower inner surface, both orthogonal to the axial direction of the piston; a radially inward-most, bottom surface connecting the upper and lower inner surfaces; and oil drain holes, each having an opening thereof located on the bottom surface. The ring groove has an axial width slightly greater than the width of the two-piece oil ring.

Abstract: A ring groove for a two-piece oil ring of a piston is provided that has ring body equipped with a coil expander, wherein the ring body has an upper outer surface and a lower outer surface, both orthogonal to the axial direction of the piston. The ring groove also has an upper inner surface and a lower inner surface, both orthogonal to the axial direction of the piston; a radially inward-most, bottom surface connecting the upper and lower inner surfaces; and oil drain holes, each having an opening thereof located on the bottom surface. The ring groove has an axial width slightly greater than the width of the two-piece oil ring.

Abstract: A piston is disclosed having both downwardly and upwardly inclined piston ring grooves, the grooves being angled less than approximately ten degrees with respect to a horizontally extending axis. In a preferred embodiment, the grooves are less than approximately three degrees in inclination and in a most preferred embodiment, the inclination is less than approximately one degree. The grooves for the combustion seal are angled upwardly from an outer diameter of the piston to adjust for thermal drooping of the piston rings received within the grooves. The grooves for the oil-control seal are angled downwardly so that oil is scraped downwardly, but the oil control ring hydroplanes over the oil when the piston moves upwardly.

Abstract: Pump apparatus according to the present invention may comprise a pump body having a bore therein and a piston mounted within the bore so that the piston may be reciprocated within the bore between first and second positions. A sleeve seal assembly mounted to the pump body contacts the piston as the piston moves between the first and second positions. A piston seal assembly mounted to the piston contacts the bore in the pump body and is located on the piston so that the piston seal assembly does not contact the sleeve seal assembly as the piston is reciprocated between the first and second positions within the bore of the pump body.

Abstract: A piston ring device for use in a combustion engine of a vehicle includes a compressing ring, a zigzag-shape oil ring and an auxiliary ring which is piled up from the auxiliary ring and combined with each other, so that the piston ring device can be easily assembled and disassembled and reducing a rubbing loss so as to minimize any power loss.