Patent ID: 8720397

Claim:
A compensating arrangement for a variable compression ratio engine, the compensating arrangement comprising a piston ( 1 ) reciprocally movable in a guiding sleeve ( 2 ) having an open end ( 24 ) in communication with a combustion cylinder of the engine and a closed end ( 11 ), wherein the piston ( 1 ) has a shape of a hollow cylindrical tube having a first portion ( 25 ) with a closed end ( 31 ) movable in a first portion ( 28 ) of the guiding sleeve ( 2 ) and a second portion ( 26 ) having a diameter larger than the diameter of the first portion ( 25 ) and an open end ( 32 ) and movable in a second portion ( 29 ) of the guiding sleeve ( 2 ), and wherein the arrangement further comprises a first sealing ( 4 ) between the first portion ( 25 ) of the piston ( 1 ) and the first portion ( 28 ) of the guiding sleeve ( 2 ), a second sealing ( 8 ) between the second portion ( 26 ) of the piston ( 1 ) and the second portion ( 29 ) of the guiding sleeve, a first pneumatic cushion ( 20 ) formed between the closed end ( 11 ) of the guiding sleeve ( 2 ) and the internal surface of the piston ( 1 ) such as to limit the movement of the piston ( 1 ) towards the closed end ( 11 ) of the guiding sleeve ( 2 ), a second pneumatic cushion ( 19 ) formed between the guiding sleeve ( 2 ) and the external surface of the piston ( 1 ) limited by the first sealing ( 4 ) and the second sealing ( 8 ) such as to limit the movement of the piston ( 1 ) towards the open end ( 24 ) of the guiding sleeve ( 2 ), and a check valve ( 18 ) configured to provide pneumatic medium to the second pneumatic cushion ( 19 ) in amount dependent on the displacement of the piston ( 1 ) during its movement towards the closed end ( 11 ) of the guiding sleeve ( 2 ), characterized in that the closed end ( 11 ) of the guiding sleeve ( 2 ) is formed by a movable partition ( 11 ), wherein the position of the movable partition defines the maximum volume of the first pneumatic cushion ( 20 ) and wherein the movable partition ( 11 ) comprises an inlet conduit ( 15 ) with a check valve ( 16 ) for providing pneumatic medium to the first pneumatic cushion ( 20 ).