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.

A crankshaft is rotatably supported by an engine block and rotatable about a crank axis. An eccentric shaft is rotatably supported within the engine and rotatable about an eccentric shaft axis, wherein the eccentric shaft axis is parallel to and distal from the crank axis. A speed change mechanism interlinks movement of the eccentric shaft and the crankshaft. The speed change mechanism selectively varies a ratio of a rotational speed of the eccentric shaft relative to a rotational speed of the crankshaft from 1:1 to one of: −8:1, −6:1, −4:1, −2:1, −1:1, −0.5:1, 0:1, 0.5:1, 1:1, 2:1, 4:1, 6:1, and 8:1, thereby causing the eccentric shaft to rotate at a speed different from the crankshaft and varying a rotational position of the eccentric shaft relative to the crankshaft.

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.

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.

Provided is a compression ratio varying mechanism, including: a discharge oil passage connected to a first hydraulic chamber; a supply oil passage connected to a hydraulic pump; a pump cylinder including a first oil storage chamber connected to the discharge oil passage and the supply oil passage and a second oil storage chamber partitioned from the first oil storage chamber by a plunger; a branch oil passage connected to the second oil storage chamber; and an orifice provided in the branch oil passage.

An engine assembly includes a crankshaft, a control shaft, a drive gear fixed to the crankshaft, a carrier, a first planetary gear set, an actuator, and a second planetary gear set. The first planetary gear set includes a first sun gear fixed to ground, a first ring gear engaged with the drive gear, and a first planet gear rotatably mounted on the carrier and engaged with the first ring gear and the first sun gear. The second planetary gear set includes a second sun gear fixed to the actuator, a second ring gear coupled with the control shaft, and a second planet gear rotatably mounted on the carrier and engaged with the second ring gear and the second sun gear. The actuator is operable to rotate the second sun gear and thereby adjust a ratio of a rotational speed of the crankshaft to a rotational speed of the control shaft.

An engine assembly includes a crankshaft, a control shaft, a drive gear fixed to the crankshaft, a carrier, a first planetary gear set, an actuator, and a second planetary gear set. The first planetary gear set includes a first sun gear fixed to ground, a first ring gear engaged with the drive gear, and a first planet gear rotatably mounted on the carrier and engaged with the first ring gear and the first sun gear. The second planetary gear set includes a second sun gear fixed to the actuator, a second ring gear coupled with the control shaft, and a second planet gear rotatably mounted on the carrier and engaged with the second ring gear and the second sun gear. The actuator is operable to rotate the second sun gear and thereby adjust a ratio of a rotational speed of the crankshaft to a rotational speed of the control shaft.

A method can include: providing a connecting rod device disposed inside of a cylinder of an engine, the connecting rod device coupled to a piston head and extending therefrom, the connecting rod device including a variable-length connecting rod and a connecting rod magnet movably coupled to the variable-length connecting rod; and adjusting a length of the connecting rod by supplying a current to pass through a solenoid wrapped around the cylinder, the current passing through the solenoid generating a magnetic field which activates the connecting rod magnet. The activation of the connecting rod magnet can cause an increase or a decrease of the length of the connecting rod.

Methods and systems for damping an impact velocity in an engine system are provided. In one example, the engine system comprises a variable compression ratio (VCR) mechanism including a rod length adjustment assembly configured to adjust a distance between a crankshaft interface and a piston interface. The rod length adjustment assembly also includes a fluid control circuit including a damping cavity positioned between a first rod section and second rod section and configured to dampen a relative motion between the first and second rod sections during a compression ratio adjustment to reduce noise, vibration, and/or harshness (NVH).

A variable compression ratio engine is provided, which includes a connecting rod including a small end connected to a piston through a piston pin, and a big end connected to a crankshaft through a crank pin, a gear eccentric sleeve installed on at least one of the piston pin and the crank pin, and at least one rack engaged with a gear formed on an outer circumferential surface of the gear eccentric sleeve at one side thereof