| 摘要 |
<p>A piston for a reciprocating internal combustion engine includes at least one pressure ring (14) installed in an outer surface of the piston main body adjacent to the piston head. The pressure (14) ring has a double-angle butt end construction comprising an outer circumferential surface (2) slidably contacting the inner circumferential wall of the cylinder, a radially extending first butt flat end face (3), and a side wall (8) facing the combustion chamber side, namely the high-pressure side, of the engine piston chamber. Only a corner portion formed on the combustion chamber side of the pressure ring by the outer circumferential surface (2), flat end face (3) and side wall (8) is partially cut away to form a notch (44) which is contiguous to the outer circumferential surface (2), and face (3) and side wall (8). The pressure ring (14) further includes a radially extending second butt flat end face (7) opposing the first flat end face (3), and a rib (55) projecting circumferentially from the second flat end surface (7) only at a position corresponding to the notch (44), the rib (55) having a shape which is complementary to that of the notch (44) for being gastightly received by the notch (44) when the pressure ring (14) is installed in an outer circumferential groove of the piston main body.</p> |
