Abstract: A device for adjusting the compression ratio of a variable compression ratio engine including a hydraulic double-acting control actuator (8) including an upper chamber (121) and a lower chamber (122) and at least one actuator piston (13) connected to a control rack (7) includes: at least two balls (401, 402) or valve elements each resting on a seat (403, 404) and closing off respectively one and the other end of a transfer channel (405) connecting the upper chamber and the lower chamber of the control actuator, the balls acting as a nonreturn valve element when they are held on their seat by a spring (408, 409) in order to allow the hydraulic fluid to pass in only one direction; and lifting elements (410) making it possible to raise the balls from their seat so that the balls allow the hydraulic fluid to pass in both directions.

Abstract: A pressure device maintains the raceways (48, 160 to 165) of the main moving components (3, 5, 7 and 40) of a variable compression ratio engine permanently in contact with one another and with the faces on which they rest in a cylinder case. The inventive device includes pressure elements which are solidly connected to the cylinder case (100) and which exert a pressure force on a control rack (7) having a toothed segment (75) formed by teeth (74). The pressure force is applied against a support surface (78) provided on the lower part of the rack (7).

Abstract: The invention relates to a crankshaft (9) for a variable compression ratio engine, which can be used to convert the reciprocating motion of the main moving components (2, 3, 5, 6, 40) of the variable compression ratio engine into rotational motion. The inventive device, which includes hydrodynamic bearings, has no balance weights.

Abstract: The invention relates to an oil spray lubrication and cooling device for a variable compression ratio engine, including at least one injector (701, 712, 713) which is placed in the engine block (100) of the variable compression ratio engine such as to spray oil onto at least one of the moving components of the engine. The aforementioned moving components include at least one piston (2), the lower part of which is solidly connected to a transmission element (3) that co-operates with a rolling guide device (4) and a toothed wheel (5) which co-operates with (i) a connecting rod (6) which is connected to a crankshaft (9) and (ii) a control rack (7) opposite the transmission element (3). The vertical position of the control rack in relation to the engine block (100) is controlled by a control device (12).

Abstract: The ball-lift electrohydraulic valve for a hydraulic power unit of a variable compression ratio engine includes: at least two balls or valve elements each resting on a seat to close off a duct, the first duct connecting a high-pressure circuit of the hydraulic power unit to one of the stages of a multi-stage pressure amplifier that the power unit includes, while the second duct connects a low-pressure circuit of the power unit to the stage, the balls operating like a nonreturn valve element when they are held on their seat by a spring in order to allow the oil contained in the stage to go to the high-pressure circuit but not to return therefrom, and in order to allow the oil originating from the low-pressure circuit to enter the stage but not to leave it again, and lifting element making it possible to lift the balls or valve elements from their seat and allow the oil both to enter and leave the stage of the multi-stage pressure amplifier.

Abstract: A ball-lift device with screw for a variable compression ratio engine having a hydraulic double-acting control actuator (8) including an upper chamber (121) and a lower chamber (122) and at least one actuator piston (13) connected to a control rack (7) includes: at least two balls (401, 402) or valve elements each resting on a seat (403, 404) and closing off respectively one and the other end of a transfer channel (405) connecting the upper chamber and the lower chamber of the control actuator, the balls acting as a nonreturn valve element when they are held on their seat by a spring (408, 409) in order to allow the hydraulic fluid to pass in only one direction; and lifting element (410) including at least one electric motor (480) designed to rotate at least one screw (481, 482) making it possible to lift from or place on its seat at least one ball.

Abstract: The hydraulic supply for a variable compression ratio engine includes a compressed-air oil pressure accumulator (251), connected to a multi-stage pressure amplifier (241) having at least one stage the outlet pressure of which acts upon the pressure jack(s) (170) of the engine, the outlet pressure being controlled by at least one stage selector solenoid (285), and connected to the control jack(s) (8).

Abstract: An electrohydraulic device for controlling the compression ratio of a variable compression-ratio engine, includes at least one dual-flow electrovalve (81) with no check valve and capable of opening and closing at least one hydraulic fluid duct (83) between the upper chamber (121) and the lower chamber (122) of a control jack (8), at least one position sensor (82) of a control rack (7), an angular position sensor (88) of the crankshaft (9) of the engine for adjusting the compression ratio, and at least one calculator (84).

Abstract: An engine block and cylinder head assembly for a variable compression ratio engine, includes a common cylinder head (300) which co-operates with a cylinder case (100) in order to close (i) the end of at least one cylinder (110) of the engine at the combustion chamber (302) thereof and (ii) the end of at least one cylinder (112) of a control jack (8) of the engine at the upper chamber (121) of the jack, the cylinder case containing all of the components of the mobile coupling system (2, 3, 4, 5, 6, 7, 9, 10, 13) of the variable compression ratio engine.

Abstract: A device for measuring the effective volumetric ratio of at least one cylinder in a variable compression-ratio engine, includes at least one target passage sensor (91) attached on the cylinder casing (100) and detecting the passage of at least one target (92) connected to the piston (2) of the engine, the target passage sensor interacting with at least one angular position sensor of the crankshaft (93) of the engine, and one calculator (94).

Abstract: An electromechanical device (800) which can be used to control the compression ratio of a variable compression ratio engine, includes mechanical elements for transmitting movement (801) between at least one electric engine (802) and at least one control rod (20) of a control jack (8) of a control device (12) for adjusting the vertical position of a control rack (7) of the variable compression ratio engine.

Abstract: An adjustment device for a variable compression ratio engine. An engine block (100) is equipped internally with a transmission device (1) including, for at least one piston (2), a transmission member (3) which co-operates with (i) a rolling guide device (4) and (ii) a sprocket wheel (5), the sprocket wheel (5) co-operating with a control rack (7), on the opposite side from the transmission member (3). Moreover, the vertical position of the control rack in relation to the engine block (100) is adjusted by a control device (12). In addition, the adjustment device includes: elements for adjusting the position of the transmission device (1), which are disposed at the rolling guide device (4); and elements for adjusting the working clearance of the transmission device (1), which are disposed at the control rack (7).

Abstract: An adjustment device for a variable compression ratio engine. An engine block (100) is equipped internally with a transmission device (1) including, for at least one piston (2), a transmission member (3) which co-operates with (i) a rolling guide device (4) and (ii) a sprocket wheel (5), the sprocket wheel (5) co-operating with a control rack (7), on the opposite side from the transmission member (3). Moreover, the vertical position of the control rack in relation to the engine block (100) is adjusted by a control device (12). In addition, the adjustment device includes: elements for adjusting the position of the transmission device (1), which are disposed at the rolling guide device (4); and elements for adjusting the working clearance of the transmission device (1), which are disposed at the control rack (7).

Abstract: A hydraulic valve actuator for reciprocating engine includes at least a hydraulic cylinder (3) for opening at least one valve (2) via at least one valve opening selector (11) with at least one hydraulic positive displacement pump (4) whereof the hydraulic fluid supplied at the output can be forced into a high pressure circuit (10) by at least one pump outlet closure (8), the valve (2) capable of being maintained opened by an opening non-return valve (24), then of being reseated by a valve closing selector (25) which directs the hydraulic fluid contained in the hydraulic cylinder (3) in the hydraulic positive displacement pump (4) input by co-operating with a pump input non-return valve (26).

Abstract: A hydraulic valve actuator for reciprocating engine includes at least a hydraulic cylinder (3) for opening at least one valve (2) via at least one valve opening selector (11) with at least one hydraulic positive displacement pump (4) whereof the hydraulic fluid supplied at the output can be forced into a high pressure circuit (10) by at least one pump outlet closure (8), the valve (2) capable of being maintained opened by an opening non-return valve (24), then of being reseated by a valve closing selector (25) which directs the hydraulic fluid contained in the hydraulic cylinder (3) in the hydraulic positive displacement pump (4) input by co-operating with a pump input non-return valve (26).

Abstract: A mechanical transmission device for a variable cylinder capacity engine includes at least a cylinder (10) wherein moves a piston (2), which is integral in its lower portion with a transmission member (3) co-operating through a small-sized rack (37) with a roller bearing guide device (4) and through another large-sized rack (35) with a sprocket wheel (5) linked to a connecting rod (6), a control member (7) having a large-sized rack (73) co-operating with the sprocket wheel (5), elements for fixing (24, 31) the piston (2) on the transmission member (3) which provide a preload for clamping it and ensure its centring, linking elements (11, 12; 71, 72) for rigidifying the transmission (3) and control (7) members and for increasing the flexural strength of the teeth of the large-sized racks (35, 73) and elements for lightening (56) the sprocket wheel (5) which maintain its rigidity and load capacity.

Abstract: The invention concerns a mechanical transmission device for a variable cylinder capacity engine comprising at least a cylinder (10) wherein moves a piston (2), which is integral in its lower portion with a transmission member (3) co-operating through a small-sized rack (37) with a roller bearing guide device (4) and through another large-sized rack (35) with a sprocket wheel (5) linked to a connecting rod (6), a control member (7) comprising a large-sized rack (73) co-operating with the sprocket wheel (5), means for fixing (24, 31) the piston (2) on the transmission member (3) which provide a preload for clamping it and ensure its centring, linking means (11, 12; 71, 72) for rigidifying the transmission (3) and control (7) members and for increasing the flexural strength of the teeth of the large-sized racks (35, 73), and means for lightening (56) the sprocket wheel (5) which maintain its rigidity and load capacity.

Abstract: A mechanical transmission device for an engine with variable volume displacement comprising a piston (2) interlocked in its lower part with a control rack (3), co-operating with a ball-bearing guiding device (4) and with a gear assembly (5) integral with a connecting rod (6) for transmitting movement between the piston and the connecting rod.