Transmission device of an engine, particularly for an engine with variable compression rate and/or variable displacement

A transmission device for an engine with a variable compression rate and/or a variable displacement, the transmission device comprising, in a cylinder housing:

• a combustion piston capable of moving in a combustion cylinder of the engine and secured to a transmission member;
• a gear linked with a first rack of the transmission member and providing transmission of the movement between the combustion piston and a crankshaft of the engine;
• a connecting rod linked, at a first end, with the gear and linked, at a second end, with the crankshaft, a major axis of the crankshaft defining a longitudinal direction;
• and
• a control member linked with the gear and secured to a control piston;
• and
• wherein the combustion piston and the transmission member are slidably linked with the cylinder housing in a main direction, the main direction defined by an axis of the combustion cylinder, the sliding link providing five degrees of blocking and allowing a single translation movement in the main direction;
• wherein the sliding link is provided by a roller bearing on a plate of the cylinder housing and on the transmission member and is provided by a rib and a guide groove adapted to receive the rib, with one being arranged on the roller and the other one being arranged on the transmission member;
• wherein a link between the gear and the connecting rod is an annular linear link in the longitudinal direction;
• wherein a link between the gear and the transmission member is formed of a rack and pinion link and an annular linear link in the main direction;
• wherein a link between the gear and the control member is formed of a rack and pinion link and an annular linear link in the main direction.