| 摘要 |
PURPOSE:To make a piston ring unnecessary to eliminate friction force, and as well to obtain a high-efficient heat gas engine having a small output power, for teaching aids, with the use of air, by forming a plurality of annular grooves in the fitting surfaces of a displacer piston and a power piston. CONSTITUTION:The fitting surface of a displacer piston 15 with respect to a high temperature expansion cylinder 3 and the fitting surface of a power piston 16 with respect to a low temperature compression cylinder 7 are respectively formed with a pluratility of annular grooves 41, 42, and further, the fitting surface of a displacer guide 17 with respect to a piston body 32 is formed with a plurality of annular grooves 43. With this arrangement, labyrinth effect is obtained through these grooves in several stages when air in a working space leaks between each fitting surfaces, thereby the amount of leak air may be small. |
