Reciprocating piston expansion machine and piston for same

摘要

The piston has a piston head (1) with a groove (4) running in a circumferential direction, where the groove receives a piston ring (5). The piston shaft (3) includes a pin boss (17) and a guiding surface (6) at an outer circumference, where the pin boss receives a piston pin and the guiding surface guides the piston along a cylinder inner wall. An outer diameter of a piston neck (2) is smaller than an outer diameter of the piston head and/or the piston shaft. The piston neck exhibit a length, which closely corresponds to a stroke of the piston in an installed state. An independent claim is also included for a reciprocating piston expansion machine comprising cylinders.