A connecting rod for changing a compression ratio of an internal combustion engine includes a connecting rod head, a connecting rod pin, and an interlock. The connecting rod pin is supported by an eccentric of the connecting rod at a variable distance within the connecting rod head. The connecting rod head or the connecting rod pin includes a fluid chamber and the eccentric has a projection extending into the fluid chamber. In the alternative, the eccentric delimits a fluid chamber and the connecting rod head or the eccentric has a projection extending into in the fluid chamber. A fluid pressure in the fluid chamber exerts a force on the projection to change the position of the eccentric. In a locking position, the interlock inhibits rotation of the eccentric relative to the connecting rod head and the interlock is configured to be releasable.

There is presented various embodiments disclosed in this application, including an improved crankshaft system using a load connecting member which provides a greater maximum torque angle than a conventional system, thereby improving efficiency and power.

The variable compression ratio piston system for an engine adjusts the compression ratio of the engine piston by way of hydraulic fluid distributed between a pair of chambers formed in a pair of bores receiving control pistons mechanically coupled to the engine piston. A control valve selectively permits flow of hydraulic fluid between the high compression ratio line and the low compression ratio line. A variable force solenoid controlled by an engine control unit preferably controls the position of the control valve. The position of the spool controls whether hydraulic fluid can flow toward the first chamber, toward the second chamber, or not at all. Flow of hydraulic fluid is actuated by alternating forces from inertial and combustion forces on a crankshaft from operation of the engine.

A variable length connecting rod includes a connecting rod body, an eccentric member, a first piston mechanism, a second piston mechanism and a flow-direction switching mechanism. The eccentric member, the first piston member, the second piston member and the flow-direction switching mechanism are provided in the connecting rod body. The first piston mechanism and the second piston mechanism are configured to pivot the eccentric member. The connecting rod body has a control oil passage that communicates with a first opening of the connecting rod and the flow-direction switching mechanism. The flow-direction switching mechanism is switched between the first state and the second state by switching pins. The switching pins are disposed in the connecting rod body such that directions in which the switching pins are operated are angled with respect to a plane perpendicular to an axis of the first opening.

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.

A control device for an internal combustion engine has a controller configured to control a fuel injection valve arranged to directly inject a fuel into a combustion chamber, and a variable compression ratio mechanism arranged to vary an upper dead center position of a piston, and thereby to vary a compression ratio of the internal combustion engine. The controller is configured to control a fuel cut by which the fuel injection from the fuel injection valve is stopped, when a predetermined fuel cut condition is satisfied during a traveling of a vehicle. The fuel injection from the fuel injection valve is restarted when a predetermined fuel cut recovery condition is satisfied during the fuel cut.

A variable length connecting rod includes: a connecting rod body; an eccentric member which can swivel with respect to the connecting rod body and in which the effective length of the variable length connecting rod is changed when swiveled; a first piston mechanism making the eccentric member swivel in one direction when hydraulic fluid is fed; a second piston mechanism making the eccentric member swivel in the opposite direction when hydraulic fluid is fed; and a flow direction changing mechanism switching flow directions of hydraulic fluid between the first and second piston mechanisms. The first piston mechanism and second piston mechanism are formed so that a first cylinder volume defined by a stroke length of the first piston and a cross-sectional area of the first cylinder is equal to a second cylinder volume defined by a stroke length of the second piston and a cross-sectional area of the second cylinder.

A variable length connecting rod includes a connecting rod body, an eccentric member, a switching mechanism and a stopping mechanism. The eccentric member is provided at a small diameter end of the connecting rod body. The eccentric member rotates such that an effective length of the variable length connecting rod is varied. The switching mechanism includes a hydraulic piston connected to the eccentric member. The eccentric member reaches a first position when the switching mechanism is in a first state. The eccentric member reaches a second position when the switching mechanism is in a second state. The stopping mechanism includes a stopping member that abuts against or engages with the eccentric member or the hydraulic piston such that the eccentric member is maintained at an intermediate position between the first position and the second position.

A connecting rod (10) has a crankpin bearing eye (11) attached to a crankshaft (38) and a connecting-rod bearing eye (12) attached to a piston. An eccentric adjustment device (13) adjusts an effective connecting rod length and has eccentric rods (15, 16) that engage a lever (14) of the eccentric adjustment device (13). Each eccentric rod (15, 16) has a piston (20, 21) guided in a hydraulic chamber (22, 23). The hydraulic chambers (22, 23) can be charged with hydraulic oil from first hydraulic lines (41) that lead to the crankpin bearing eye (11) and second hydraulic oil lines (24, 25) that lead from the crankpin bearing eye (11). Check valves (26, 27) prevent a backflow of hydraulic oil back into the second hydraulic lines (24, 25). At least one filter prevents an ingress of contaminants from the crankshaft into the hydraulic chambers (22, 23) via the hydraulic oil.

A variable compression ratio internal combustion engine comprises a crankshaft and a connecting rod. The connecting rod comprises a connecting rod body, a first hydraulic cylinder, a first hydraulic piston, a second hydraulic cylinder, a second hydraulic piston, a linking member, a hydraulic oil path, and a spool between a first operating position permitting supply of hydraulic oil from the second hydraulic cylinder to the first hydraulic cylinder, and a second operating position permitting supply of hydraulic oil from the first hydraulic cylinder to the second hydraulic. The variable compression ratio internal combustion engine further comprises a biasing member arranged inside the crank pin and biasing the spool so as to selectively switch a position of the spool between the first operating position and the second operating position.