Abstract: A crankshaft, for use with a variable compression ratio engine having a connecting rod and a rod bearing, includes a crankpin adapted to be coupled to the connecting rod with the rod bearing disposed between the crankpin and the connecting rod. The crankpin includes a circumferential surface having first and second side surface portions and a main surface portion disposed between the side surface portions. The main surface portion is configured to receive the rod bearing. The first side surface portion has a first aperture disposed at least partially outwardly of the rod bearing when the rod bearing is received on the main surface portion of the crankpin and the crankpin is coupled to the connecting rod. The crankpin further defines, at least partially, a first fluid passage for supplying pressurized fluid to the first aperture, such that the fluid is useable to vary compression ratio of the engine.

Abstract: A connecting rod assembly is provided for varying a compression ratio of an internal combustion engine having a crankshaft and a piston. The assembly includes a first portion adapted to be connected to the crankshaft and having a cylindrical aperture. The assembly further includes a second portion adapted to be connected to the piston and movable with respect to the first portion. In addition, the assembly includes a locking element having a cylindrical portion that is disposed at least partially in the cylindrical aperture. The locking element is movable between an unlocked position and a locked position for locking the second portion at a first position relative to the first portion, wherein the first position corresponds to a first compression ratio of the engine.

Abstract: A crankshaft, for use with a variable compression ratio engine having a connecting rod and a rod bearing, includes a crankpin adapted to be coupled to the connecting rod with the rod bearing disposed between the crankpin and the connecting rod. The crankpin includes a circumferential surface having first and second side surface portions and a main surface portion disposed between the side surface portions. The main surface portion is configured to receive the rod bearing. The first side surface portion has a first aperture disposed at least partially outwardly of the rod bearing when the rod bearing is received on the main surface portion of the crankpin and the crankpin is coupled to the connecting rod. The crankpin further defines, at least partially, a first fluid passage for supplying pressurized fluid to the first aperture, such that the fluid is useable to vary compression ratio of the engine.

Abstract: A system and method for controlling a pressure responsive device in an engine is provided. The device can vary a compression ratio in an engine cylinder. The method includes supplying fluid pressure to the pressure responsive device to change a compression ratio in the cylinder. The method further includes indicating when the device has deteriorated response. Finally, the method includes increasing the fluid pressure to the device to change the compression ratio in the cylinder in response to the indication.

Abstract: A system and method for controlling an engine is provided. The engine includes first and second pressure responsive devices varying compression ratios in first and second engine cylinders, respectively. The method includes commanding the first and second devices to decrease compression ratios in the first and second cylinders, respectively. The method further includes indicating when the first device has not decreased a compression ratio in the first cylinder. Finally, the method includes commanding the second device to increase a compression ratio in the second cylinder to reduce engine torque fluctuations.

Abstract: A connecting rod assembly is provided for varying a compression ratio of an internal combustion engine having a crankshaft and a piston. The connecting rod assembly includes a first portion adapted to be connected to the crankshaft, and a second portion adapted to be connected to the piston and movable with respect to the first portion. The connecting rod assembly further includes a locking mechanism disposed between the first and second portions. The locking mechanism includes a rotatable locking element that is configured to lock the second portion at a first position relative to the first portion. Furthermore, the first position corresponds to a first compression ratio of the engine.

Abstract: A system and method for controlling an engine is provided. The engine includes first and second pressure responsive devices varying compression ratios in first and second engine cylinders, respectively. The method includes commanding the first and second devices to decrease compression ratios in the first and second cylinders, respectively. The method further includes indicating when the first device has not decreased a compression ratio in the first cylinder. Finally, the method includes commanding the second device to increase a compression ratio in the second cylinder to reduce engine torque fluctuations.

Abstract: A system and method for controlling a pressure responsive device in an engine is provided. The device can vary a compression ratio in an engine cylinder. The method includes supplying fluid pressure to the pressure responsive device to change a compression ratio in the cylinder. The method further includes indicating when the device has deteriorated response. Finally, the method includes increasing the fluid pressure to the device to change the compression ratio in the cylinder in response to the indication.

Abstract: A variable length connecting rod (12) has a first locking mechanism (36) for releasably locking connecting rod parts in a first effective length setting (FIG. 7) for the rod, and a second locking mechanism (38) for releasably locking the connecting rod parts in a second effective length setting to change the compression ratio for an engine cylinder. When a length change is to be made, hydraulic fluid unlocks a locked one of the locking mechanisms, allowing inertial force to effect the length change during an engine cycle. At completion of a length change, the other locking mechanism automatically unlocks.

Abstract: A connecting rod assembly is provided for varying a compression ratio of an internal combustion engine having a crankshaft and a piston. The assembly includes a first portion adapted to be connected to the crankshaft and having a cylindrical aperture. The assembly further includes a second portion adapted to be connected to the piston and movable with respect to the first portion. In addition, the assembly includes a locking element having a cylindrical portion that is disposed at least partially in the cylindrical aperture. The locking element is movable between an unlocked position and a locked position for locking the second portion at a first position relative to the first portion, wherein the first position corresponds to a first compression ratio of the engine.

Abstract: A connecting rod assembly is provided for varying a compression ratio of an internal combustion engine having a crankshaft and a piston. The connecting rod assembly includes a first portion adapted to be connected to the crankshaft, and a second portion adapted to be connected to the piston and movable with respect to the first portion. The connecting rod assembly further includes a locking mechanism disposed between the first and second portions. The locking mechanism includes a rotatable locking element that is configured to lock the second portion at a first position relative to the first portion. Furthermore, the first position corresponds to a first compression ratio of the engine.

Abstract: A desmodromic drive (30) for imparting reciprocal translation to a valve (32) has a cam ring (52) that rotates about an axis (42), a follower (50) that reciprocates with axial motion as the ring rotates, an endless cam track (69) on the ring, and rollers (76, 78) on the follower that ride along the cam track as the ring rotates. A follower guide (48) guides the follower for axial. Rollers (60, 62) constrain the follower against rotation on the follower guide.

Abstract: A variable length connecting rod (12) has a first locking mechanism (36) for releasably locking connecting rod parts in a first effective length setting (FIG. 3) for the rod, and a second locking mechanism (38) for releasably locking the connecting rod parts in a second effective length setting (FIG. 2) to change the compression ratio for an engine cylinder. When a length change is to be made, hydraulic fluid unlocks a locked one of the locking mechanisms, allowing inertial force to effect the length change during an engine cycle. At completion of a length change, the other locking mechanism automatically unlocks.

Abstract: A variable length connecting rod (12) has a first locking mechanism (36) for releasably locking connecting rod parts in a first effective length setting (FIG. 7) for the rod, and a second locking mechanism (38) for releasably locking the connecting rod parts in a second effective length setting to change the compression ratio for an engine cylinder. When a length change is to be made, hydraulic fluid unlocks a locked one of the locking mechanisms, allowing inertial force to effect the length change during an engine cycle. At completion of a length change, the other locking mechanism automatically unlocks.

Abstract: A system for varying a compression ratio of an internal combustion engine includes: at least one sensor for measuring an operating condition of the internal combustion engine; a variable compression ratio apparatus for varying the effective length of a connecting rod, the compression ratio apparatus itself comprising a bearing retainer disposed between the connecting rod and a crank pin, the bearing retainer having an inner surface in communication with the crank pin and an outer surface in communication with the connecting rod, the connecting rod being axially movable relative to the bearing retainer along a longitudinal axis of the connecting rod to effect a selective displacement of the connecting rod relative to the bearing retainer, the displacement thereby causing a change in the effective length of the connecting rod and a desired compression ratio of the internal combustion engine; and an engine controller coupled to the internal combustion engine, the sensor and the variable compression ratio apparat

Abstract: An apparatus for selectively varying a compression ratio of an internal combustion engine includes a bearing retainer disposed between a connecting rod and a crankpin of an internal combustion engine, the bearing retainer having an inner surface in communication with the crankpin and an outer surface in communication with the connecting rod, the connecting rod being axially movable relative to the bearing retainer along a longitudinal axis of the connecting rod to effect a selective displacement of the connecting rod relative to the bearing retainer, the displacement thereby causing a change in the effective length of the connecting rod and the compression ratio of the internal combustion engine.

Abstract: An engine 20 has an oiling system including a pump (46) that delivers oil under nominal engine lubrication pressure to lubricate moving surfaces of the engine mechanism (42). The system also has first and second control passages (30, 32) to effect engine compression ratio change by operating connecting rod length change mechanisms (26A, 26B, 26C). Selectively operated hydraulic control devices cause pressure in the first passage to be greater than pressure in the second passage to effect an increase in engine compression ratio and pressure in the second passage to be greater than pressure in the first passage to effect a decrease in engine compression ratio. Multiple embodiments of the invention are disclosed.

Abstract: A variable length connecting rod 13 for changing a compression ratio of an engine is provided. The connecting rod 13 includes a first locking assembly 36 for locking the connecting rod 13 in a first effective length setting corresponding to a high compression ratio. The connecting rod 13 further includes a second locking assembly 38 for releasably locking the connecting rod 13 in a second effective length setting corresponding to a low compression ratio. When a length change is initiated, hydraulic fluid unlocks one of the locking assemblies 36, 38, allowing inertial force to effect the length change during an engine cycle. At completion of a length change, the other locking assembly 36, 38 automatically locks. The locking assemblies 36, 38 are self-contained units that are assembled to a bearing retainer 24.

Abstract: A variable length connecting rod (12) has a first locking mechanism (36) for releasably locking connecting rod parts in a first effective length setting (FIG. 7) for the rod, and a second locking mechanism (38) for releasably locking the connecting rod parts in a second effective length setting to change the compression ratio for an engine cylinder. When a length change is to be made, hydraulic fluid unlocks a locked one of the locking mechanisms, allowing inertial force to effect the length change during an engine cycle. At completion of a length change, the other locking mechanism automatically unlocks.