Four-cycle internal-combustion engines provided with means whereby the clearance-space is varied in unison with the movement of the working piston, being as far as practicable eliminated at the end of the exhaust-stroke and greatest at the end of the compression-stroke, whereby to secure a more complete removal of the residual burned gases from the
cylinder and combustion-chamber of the engine. The clearance-space is ordinarily varied by causing the strokes of the working piston to vary in length, and the four strokes required for a complete cycle are frequently performed during a single revolution of the main shaft of the engine.
SEE OR SEARCH CLASS
92, Expansible Chamber Devices,
84, for an expansible chamber device having a resilient means interposed between the working member and a relatively movable power transmission element.
