| 摘要 |
PURPOSE:To improve starting performance by installing in slidable ways an inner piston which varies the capacity of a combustion chamber, in a piston body, and increasing the compression ratio on starting by means of the taper part on the bottom part of the inner piston and wedge-shaped guides connected with a shape-memorizing alloy. CONSTITUTION:An inner piston 4 in which a cavity 3 which constitutes a combustion chamber 2 in the upper part is installed at the top part of a piston 1, in vertically slidable ways so that the capacity of the combustion chamber 2 is varied. A taper part 4a is formed on the bottom part of the inner piston 4, and two wedge-shaped guides 6 whose inner edge sides are connected by a shape- memorizing alloy 8 and the outer edge is springly pressed to the inside by a spring 7 are installed under the tapered part 4. On cold start of an engine, the shape-memorizing alloy does not operate, and the wedge-shaped guide is pressed in the direction of center by the spring 7, and the inner piston 3 rises against a spring 5, and thus compression ratio can be increased. |
