Provided is an engine, including: a cylinder; a piston accommodated in the cylinder; a combustion chamber facing the piston; a sliding portion (large-diameter portion) configured to perform a stroke motion together with the piston; a hydraulic surface of the sliding portion facing a side opposite to the combustion chamber; a hydraulic chamber, which the hydraulic surface faces; and an auxiliary hydraulic chamber, which communicates with the hydraulic chamber, and has a volume changeable in accordance with a hydraulic pressure in the hydraulic chamber.

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.

Engine for producing mechanical energy by internal combustion of a fuel includes a shaft and a crank arm attached to the shaft. The engine further includes a casing, where the interior of the casing forms a hollow cavity dimensioned to allow the crank arm to rotate within the hollow cavity and the crank arm is capable of making a seal with the interior surface of the casing to block fluid passage. The interior of the casing also includes a bypass area that allows fluid passage around the crank arm. A first valve is positioned adjacent to the bypass area and a second valve is positioned adjacent to the bypass area opposite from the first valve. The first valve and the second valve are configured to block fluid passage when closed.

A rotational combustion engine that generates force from the reciprocal motion and centripetal motion of one or more pistons that is then converted into rotational motion of a first cam and second cam wherein the cams are separated by a 2-3 degree horizontal offset and an angle of 60 degrees as well as camshaft assembly and driving shaft to provide power to an entity such as an automobile.

An expanded torque system of an internal combustion engine includes a cylinder having an upper piston bore, a lower piston bore and a lower action chamber. An upper piston is connected to the upper link rod and reciprocally moves in the upper piston bore. A linkage unit has a link block coupled to the upper link rod. A lower piston moves in the lower piston bore and is connected to the link block. A lower link rod is disposed at the lower action chamber and is pivotally coupled between the linkage unit and a lower link rod pivoting handle. A crank shaft is disposed at the lower action chamber and has a main shaft and the lower link rod pivoting handle eccentrically connected to the main shaft. An oil ring with oil outlets is disposed at the top of the lower action chamber and communicates with a main oil duct.

This invention relates to the field of opposed-piston engines having two pistons in one cylinder configured to have facing heads. Specifically, this is an engine with two crankshafts, two piston heads facing each other in a single cylinder, with the following features: compact size relative to a comparable design, improved or equivalent performance to a comparable design as a result of any of the following: locating crankshafts in a different plane from the cylinder axes; the use of shared duct structures; and the use of an embedded compressor chamber for efficient operation to cover all volumetric requirements, fulfilling the entire thermodynamic cycle, and performing in addition the sweeping and overloading of air or an air/fuel mixture in the cylinder combustion chamber in each revolution of two or more crankshafts, either with or without advancement between the crankshafts.

A cylinder assembly includes a cylinder with an inlet channel of compressed air and an outlet channel of exhaust gas located in the middle which is closed by a head and a partition. One end of a push rod goes through a linear slide bearing located in the partition. A working piston is rigidly embedded on the push rod. Bottom and top compensating pistons are separated from the working piston by spiral compensating springs. A counter-rotating combustion engine including a crank mechanism is connected to two oppositely directed identical cylinder assemblies via an engine case. The crank mechanism constitutes a crankshaft having two crank half shafts lying opposite each other and connected rotationally. The crank mechanism includes two pairs of connecting rods whose ends are rotationally connected to one of crank half shafts via a rotary shaft. The other ends of the connecting rods are connected to one of two shafts, each connected to a push rod of a cylinder assembly.

A combustion engine having a pair of two-chamber cylinders, in which double ended pistons are located and directed toward themselves oppositely by the angle 180 and compressed together via crankshafts consisting of two crank elements, which are linked rotationally backward by a spacer bearing. The compression is realized with the use of two connecting rod pairs, from which each connecting rod is linked on the one side to with one crank element, whereas the second connecting rod ends are linked to one of shafts, out of which each shaft is connected with one of pistons via a valve rod. In the middle of each cylinder's wall the outlet channel of compressed air is located as well as the outlet channel of products of combustion together with air. In the head of each cylinder and in the compartment the fuel injector, the water vapor injector and the ignition element are located.

An internal combustion engine including at least two cylinders with parallel longitudinal axes, each cylinder including an opening and a piston capable of moving in translation inside the cylinder, the respective openings of the cylinders facing each other, the pistons being in kinematic relation with a connecting rod-crank mechanism including: a spacer connecting the pistons, suitable for maintaining a fixed spacing between the pistons, the pistons being respectively attached to the arms of the spacer, a crankshaft rotating about an axis, arranged between the openings of the cylinders and between the longitudinal axes of the cylinders, the crankshaft comprising a crank pin, a rocker rotating about the crank pin, at least one connecting rod including a first so-called bottom end, rigidly attached to the spacer and a second so-called head end, rigidly attached to one of the ends of the rocker.

A pair of cylinders (2, 5) are arranged in parallel at the two sides of a crankshaft (8). The cylinders (2, 5) are respectively provided with pairs of pistons (3, 4, 6, 7). The crankshaft (8) has a pair of crankpins (12, 13). The axes of these crankpins (12, 13) are slanted with respect to the axis of the crankshaft (8) in opposite directions. The crankpins (12, 13) have the rocker members (14, 15) attached to them to be able to turn. The tip ends of the arms (16) of the rocker member (14, 15) are connected to the connecting rods (11) of the corresponding pistons (3, 4, 6, 7). If the pistons (3, 4, 6, 7) reciprocate the rocker members (14, 15) engage in swinging motion and the crankshaft (8) rotates.