Bearing guide device of a combustion piston for a variable compression ratio engine

A bearing guide device of a combustion piston for a variable compression ratio engine, the device comprising:

• a synchronized roller comprising a cylindrical body and a pinion, the cylindrical body having an effective diameter that can vary as a result of a radial load when the engine is running, the synchronized roller cooperating with:
• a synchronization plate forming one piece with the engine block and comprising a first raceway for receiving the cylindrical body and a first rack for receiving the pinion;
• and
• a transmission unit forming one piece with the combustion piston and comprising a second raceway for receiving the cylindrical body and a second rack for receiving the pinion;
• wherein moving the combustion piston from a top dead center to a bottom dead center causes the pinion to move from a first position to a second position in relation to the first and second racks, wherein the first rack and/or the second rack has a different circular pitch from the circular pitch of the pinion so that the flanks of the teeth of the pinion engage on the flanks of the teeth of the first rack and/or second rack only when the pinion is in the first or second position.