A piston and a high-pressure pumping system. The piston includes a piston body and a skirt. The skirt is elastic and peripherally provided at an end of the piston body. The skirt elastically abuts against an inner wall of a cylinder chamber when the piston is placed in the cylinder chamber. The high-pressure pumping system includes a cylinder and the piston. The piston is received in the cylinder and reciprocates with respect to the inner wall of the cylinder chamber.

A piston for an internal combustion engine comprises a skirt defining an inner space of the piston and having a skirt bottom; and a target arranged under the skirt bottom to engage with a passage detector arranged in the engine. The target is supported by a holding body held at least partially inside the inner space of the piston. The present disclosure likewise relates to an engine comprising such a piston.

A piston for an internal combustion engine comprises a skirt defining an inner space of the piston and having a skirt bottom; and a target arranged under the skirt bottom to engage with a passage detector arranged in the engine. The target is supported by a holding body held at least partially inside the inner space of the piston. The present disclosure likewise relates to an engine comprising such a piston.

An internal combustion engine includes an engine main body defining a cylinder bore, a piston received in the cylinder bore, and a crankshaft rotatably supported by the engine main body and connected with the piston via a connecting rod, the piston including a skirt. The cylinder bore includes a first region defined as a range along the cylinder axial line on a side of a top dead center from a first piston position, and a second region defined as a range along the cylinder axial line on a side of the bottom dead center from a second piston position closer to the bottom dead center than the first piston position, and a connection region positioned between the first and second regions. A diameter of the cylinder bore is smaller in the first region than in the second region, and the connection region connects the first and second regions smoothly.

An internal combustion engine includes an engine main body defining a cylinder bore, a piston received in the cylinder bore, and a crankshaft rotatably supported by the engine main body and connected with the piston via a connecting rod, the piston including a skirt. The cylinder bore includes a first region defined as a range along the cylinder axial line on a side of a top dead center from a first piston position, and a second region defined as a range along the cylinder axial line on a side of the bottom dead center from a second piston position closer to the bottom dead center than the first piston position, and a connection region positioned between the first and second regions. A diameter of the cylinder bore is smaller in the first region than in the second region, and the connection region connects the first and second regions smoothly.

A piston for an internal combustion engine includes a piston head portion, a pair of piston skirt portions, and a pair of side-wall portions. Each of the side-wall portions includes a pin boss portion having a piston pin hole, and is located between the pair of piston skirt portions. There are set a first axis corresponding to a center longitudinal axis of the piston, a second axis corresponding to an axis of the piston pin holes, and a reference plane corresponding to a plane that passes through the first axis and is orthogonal to the second axis. In a cross section of the side-wall portion being parallel to both of the first axis and the second axis, a distance between the reference plane and an outer peripheral surface of the side-wall portion in the second axis direction gradually increases from a side of the piston head portion toward an intermediate portion of the side-wall portion in the direction of the first axis and gradually decreases from the intermediate portion toward a side opposite to the piston head portion.

A piston for a reciprocating-piston internal combustion engine, having a ring carrier with an outer piston crown and an inner piston crown, and comprising a piston skirt extending from the inner piston crown in the axial direction, the piston skirt having at least one at least partially arcuately formed guide surfaces, the at least one guide surface being disposed in the arcuately formed area at a distance from the ring carrier, which is adjacent in the axial direction, in such a way that a gap results between the ring carrier and the guide surface, the piston skirt and the ring carrier being connected to each other via at least one reinforcing rib, which extends transversely over the inner piston crown.

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.

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.

A piston member for a high-pressure pump for pumping fluid in a sample separation apparatus, wherein the piston member comprises a piston configured for being mountable to reciprocate in a piston chamber for displacing fluid, and a sealing for sealing between the piston member and the piston chamber when the piston member is mounted in the piston chamber to reciprocate, wherein the sealing is mounted on the piston so as to reciprocate together with the piston.