VALVE TIMING GEAR FOR TWO-STROKE INTERNAL COMBUSTION ENGINE Russian patent published in 1998 - IPC

FIELD: mechanical engineering; forced timing in piston machines, two-stroke internal combustion engines. SUBSTANCE: device has cylinder with intake and exhaust ports and piston consisting of upper and lower parts, connecting rod and crank. Piston is articulated with connecting rod by means of insert and movable pin. Other pin is rigidly secured in shank of connecting rod and is articulated with piston by means of slide block; piston is provided with slots; number of these slots, their sizes and geometric parameters correspond to selected phases of valve timing. Device makes it possible to increase passage area and shift intake and exhaust phases relative to each other and relative to bottom dead center due to motion of piston over trajectory in form of ellipse and availability of slots on piston, thus providing for delivery of scavenge air in volume sufficient for cleaning the cylinders from combustion products and filling them with working mixture (air for diesel engine). Exhaust port closes during compression stroke before intake port, thus excluding losses of working mixture and ensuring full use of displacement volume of cylinder and possibility of supercharging. EFFECT: enhanced efficiency. 7 dwg