Abstract: A transmission device, particularly for an engine with variable compression rate and/or variable displacement, includes, 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 engaging 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 engaging, at a first end, with the gear and, at a second end, with the crankshaft; and a control member engaging with the gear and secured to a control piston. The combustion piston and the transmission member are slidably linked with the cylinder housing in a main direction.

Abstract: A piston for an internal combustion engine comprises a skirt defining an inner space of the piston and having a skirt bottom; and a target arranged under the skirt bottom to engage with a passage detector arranged in the engine. The target is supported by a holding body held at least partially inside the inner space of the piston. The present disclosure likewise relates to an engine comprising such a piston.

Abstract: An internal combustion engine comprises a connecting rod and a target arranged on one of the lateral reinforcing walls of a piston or on a foot end of the connecting rod, and a crankcase defining at least one cylinder and having at least one bore opening out under the cylinder. The engine comprises a measuring device arranged in the bore of the crankcase and having a target passage detector, and a connector and at least one cable connecting the passage detector to the connector. The target is arranged opposite the passage detector, when the piston is near a bottom dead center position.

Abstract: A crankshaft for a controlled variable compression ratio engine has an axis of rotation defining a longitudinal axis and comprises at least one crank pin, at least one journal connected by a connecting web, and at least one control element able to move translationally along the longitudinal axis in order to cooperate with an actuator of a system for adjusting the length of a connecting rod. The crankshaft is notable in that the control element, positioned at the connecting arm, comprises an annular part coaxial with the crank pin and capable of establishing continuous contact with the actuator of the system for adjusting the length of the connecting rod, regardless of the angular position of the crankshaft. The crankshaft comprises a fluidic control circuit for moving the control element along the longitudinal axis.

Abstract: An external modelling method, including applying to a nose of initial external shape F0, at least two modelling instruments I, to guide the growth of the nose cartilage and thus obtain a target final external nose shape Ff when the individual has stopped growing, which differs from a natural external shape Fn, which would be obtained naturally in the absence of intervention. A set of modelling instruments is provided, the successive shapes of which are determined to represent an evolving succession of one or more target intermediate shapes F, from the initial external nose shape F0 through to the target final external shape Ff. A method of producing the modelling instruments is provided, during which method, starting from the initial external nose shape F0, a target final shape Ff and at least one target intermediate shape F are determined. The instruments corresponding to each target shape are manufactured.

Abstract: A bearing guide device of a combustion piston for a variable compression ratio engine. The movement of the combustion piston from a top dead center to a bottom dead center drives the movement of a synchronized roller made up of a cylindrical body and a pinion from a first position to a second position relative to first and second racks. According to the disclosure, the first and/or second racks have a different circular pitch than the pinion so that the flanks of the teeth of the pinion engage with the flanks of the teeth of the first and second racks only when the pinion is in the first or second position.

Abstract: A device for controlling the compression rate of a variable compression ratio engine comprises: an actuating cylinder comprising a piston defining two chambers for receiving a pressure fluid, a pressure accumulator supplying the pressure fluid, a first fluid circuit connecting the upper chamber to the accumulator and comprising a first valve assembly for controlling the flow of the fluid in the first fluid circuit, and a second fluid circuit connecting the lower chamber to the accumulator and comprising a second valve assembly for controlling the flow of a fluid in the second fluid circuit. At least one of the fluid circuits comprises a bypass conduit arranged so as to connect one of the chambers to the accumulator. The bypass conduit comprises a non-return valve.

Abstract: A bearing guide device of a combustion piston for a variable compression ratio engine. The movement of the combustion piston from a top dead center to a bottom dead center drives the movement of a synchronized roller made up of a cylindrical body and a pinion from a first position to a second position relative to first and second racks. According to the disclosure, the first and/or second racks have a different circular pitch than the pinion so that the flanks of the teeth of the pinion engage with the flanks of the teeth of the first and second racks only when the pinion is in the first or second position.

Abstract: A transmission device, particularly for an engine with variable compression rate and/or variable displacement, includes, 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 engaging 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 engaging, at a first end, with the gear and, at a second end, with the crankshaft; and a control member engaging with the gear and secured to a control piston. The combustion piston and the transmission member are slidably linked with the cylinder housing in a main direction.

Abstract: A variable compression ratio engine comprises a stationary engine block in which movable members interact to enable a piston to translate in a combustion cylinder of the engine block, defining a stroke of the combustion piston. The engine further comprises a self-contained device for adjusting a position of a top dead center of the combustion piston, the self-contained device being connected to or built into at least one of the movable members and having a high-pressure hydraulic chamber to counteract the combustion and inertial forces at a bottom dead center, a low-pressure hydraulic chamber to counteract the inertial forces at the top dead center, at least one calibrated conduit to enable hydraulic fluid to flow between the high- and low-pressure hydraulic chambers, and return means to bring the device back to a nominal position.

Abstract: A device for compensating for the operating clearances of an engine comprising a transmission device likely to move transversely in an engine block) during an engine cycle includes a pressing device exerting a holding force on the transmission device. The holding force is adjusted to the instantaneous speed of transverse movement of the transmission device in the engine block.

Abstract: A clip-fastened raceway for a variable compression ratio engine includes: at least one curved segment whose outer surface cooperates with a raceway housed in the transmission member or in the control member of the variable compression ratio engine and whose inner surface is maintained in contact with a curved outer surface housed in the toothed wheel of the engine; at least one clip, housed in at least one of the ends of the curved segment and fastened to one or the other of the ends of the curved outer surface housed in the toothed wheel and hooking onto a hook or protrusion which the wheel includes in the vicinity of the end of its curved outer surface, the hook or protrusion being complementary to that of the clip so as to be able to cooperate with the latter.

Abstract: A clip-fastened raceway for a variable compression ratio engine includes: at least one curved segment whose outer surface cooperates with a raceway housed in the transmission member or in the control member of the variable compression ratio engine and whose inner surface is maintained in contact with a curved outer surface housed in the toothed wheel of the engine; at least one clip, housed in at least one of the ends of the curved segment and fastened to one or the other of the ends of the curved outer surface housed in the toothed wheel and hooking onto a hook or protrusion which the wheel includes in the vicinity of the end of its curved outer surface, the hook or protrusion being complementary to that of the clip so as to be able to cooperate with the latter.

Abstract: The elastic fixing for a piston (2) of a variable compression ratio engine (10) includes at least one metal rod (15) kept under tension between the piston (2) and the transmission member (3) and which applies a strong contact pressure between the base of the piston (2) and the top face of the transmission member (3), the piston (2) being tightened according to a previously calculated angle enabling the metal rod (15) consisting of a stud (16) to be subjected to a desired tension force and the tightening prestress to be reached between the piston (2) and the transmission member (3), and indexed in rotation relative to the transmission member (3), by an additional tightening which does not significantly increase the tightening pre-stress, the stud (16) continuing to elongate with the same tension force by plastic deformation.

Abstract: A clip-fastened raceway for a variable compression ratio engine includes: at least one curved segment whose outer surface cooperates with a raceway housed in the transmission member or in the control member of the variable compression ratio engine and whose inner surface is maintained in contact with a curved outer surface housed in the toothed wheel of the engine; at least one clip, housed in at least one of the ends of the curved segment and fastened to one or the other of the ends of the curved outer surface housed in the toothed wheel and hooking onto a hook or protrusion which the wheel includes in the vicinity of the end of its curved outer surface, the hook or protrusion being complementary to that of the clip so as to be able to cooperate with the latter.

Abstract: The elastic fixing for a piston (2) of a variable compression ratio engine (10) includes at least one metal rod (15) kept under tension between the piston (2) and the transmission member (3) and which applies a strong contact pressure between the base of the piston (2) and the top face of the transmission member (3), the piston (2) being tightened according to a previously calculated angle enabling the metal rod (15) consisting of a stud (16) to be subjected to a desired tension force and the tightening prestress to be reached between the piston (2) and the transmission member (3), and indexed in rotation relative to the transmission member (3), by an additional tightening which does not significantly increase the tightening pre-stress, the stud (16) continuing to elongate with the same tension force by plastic deformation.