An engine balance shaft (20) for an internal combustion engine (24) is provided having reduced total mass and rotational inertia while having sufficient bending stiffness and sufficient unbalance mass. The balance shaft (20) is formed by fixedly coupling a counterweight (56), a front bearing journal (68), a rear bearing journal (60), a tail piece (40), and a nose piece (44) to a hollow tube (52). The hollow tube (52) is hydroformed to expand the diameter of the tube and fasten the desired components to the tube (52).

A two-cylinder reciprocating engine includes a cylinder block; a first cylinder with a combustion chamber; a second cylinder with a combustion chamber; a crankshaft coupled to the first cylinder and the second cylinder with a crank angle of 270 degrees; a first exhaust port connected with the combustion chamber of the first cylinder; a second exhaust port connected with the combustion chamber of the second cylinder; a first header connected with the first exhaust port; a second header connected with the second exhaust port; and an exhaust converging section connected with the first header and the second header, wherein the first header, the second header, and the exhaust converging section are in the cylinder block.

The invention relates to a power unit, in particular for a hybrid vehicle, including a reciprocating-piston engine and at least one generator drivingly connected to the engine, wherein the engine has at least two pistons guided in at least two cylinders in a tandem arrangement, and two crankshafts, which are connected to the pistons by connection rods that run in opposite directions, and are mechanically coupled in the same phase. The engine includes a hub-hub connection with a first connection joining a first hub to a second hub such that an angular position between the first hub and the second hub is continuously adjustable on installation. The hub-hub connection also has a second connection in the form of a connection disk configured, dimensioned and arranged with support surfaces, on each of which the first hub and the second hub rest. The connection disk has a matrix with hard material elements embedded therein, in particular diamond chips, which are arranged in the support surfaces for frictional engagement of the hubs.

An internal combustion engine includes a crankcase in which a crankshaft is rotatably mounted in bearings including bearing covers, to which at least one connecting rod carrying a piston is linked. The piston is movable in a cylinder covered by a cylinder head forming a combustion chamber and gas exchange valves are arranged in the cylinder head, which are actuated by at least one camshaft, which is connected to a gear train gear wheel situated on the crankshaft via a differential gear. A mass differential gear including two balance shafts is present. The mass differential gear is situated in a gear frame and attached to the crankcase below the crankshaft and driven by a mass shaft drive gear situated on the crankshaft, which is arranged axially essentially next to the gear train gear wheel/idler gear. The gear train gear wheel/idler gear is arranged on the main bearing cover.

An engine balancing system includes an engine body. At least two slider-crank mechanisms are provided inside the engine body. One of the slider-crank mechanisms is arranged opposite to the other slider-crank mechanism. A slider in one of the slider-crank mechanisms is moved at a speed and acceleration similar to a speed and acceleration of a slider in the other slider-crank mechanism. The slider-crank mechanism includes a connecting rod and a crankshaft with a crank. One end of one of the slider-crank mechanisms and one end of the other slider-crank mechanism are connected to the same crankshaft through the crank. The balancing system can effectively eliminate first-order, second-order and higher-order vibrations generated during engine operation, thus reducing the probability of equipment damage.

A low impedance power disc is provided. The power disc is connected to a crankshaft of an engine, and includes a rotor, a connecting shaft, and a permanent magnet. The rotor is disposed separately from the permanent magnet. The connecting shaft is locked inside the rotor. A unidirectional bearing is provided and fitted on the connecting shaft. The permanent magnet is fitted on the unidirectional bearing. When the engine is running, the rotor and the permanent magnet are rotated at the same speed to generate electricity and supply the electricity to the vehicle and to charge the battery. When the engine decelerates, the rotor and the connecting shaft are decelerated synchronously with the engine, while the permanent magnet and the unidirectional bearing are continuously rotated at the speed before deceleration in order to facilitate the engine to accelerate again, so that the rotor can be quickly rotated.

A low impedance power disc is provided. The power disc is connected to a crankshaft of an engine, and includes a rotor, a connecting shaft, and a permanent magnet. The rotor is disposed separately from the permanent magnet. The connecting shaft is locked inside the rotor. A unidirectional bearing is provided and fitted on the connecting shaft. The permanent magnet is fitted on the unidirectional bearing. When the engine is running, the rotor and the permanent magnet are rotated at the same speed to generate electricity and supply the electricity to the vehicle and to charge the battery. When the engine decelerates, the rotor and the connecting shaft are decelerated synchronously with the engine, while the permanent magnet and the unidirectional bearing are continuously rotated at the speed before deceleration in order to facilitate the engine to accelerate again, so that the rotor can be quickly rotated.

An actuator arrangement for applying a torque to a shaft of a machine, in particular a reciprocating piston engine, includes: a) at least one actuator device for applying the torque; and b) at least one rotatable seismic mass coupled to the shaft. The at least one actuator device is designed to apply the torque to the shaft between the seismic mass and the shaft. A corresponding method is provided for active damping of torsional vibrations of the shaft having the actuator arrangement.

An actuator arrangement for applying a torque to a shaft of a machine, in particular a reciprocating piston engine, includes: a) at least one actuator device for applying the torque; and b) at least one rotatable seismic mass coupled to the shaft. The at least one actuator device is designed to apply the torque to the shaft between the seismic mass and the shaft. A corresponding method is provided for active damping of torsional vibrations of the shaft having the actuator arrangement.

An engine unit of a motorcycle includes a crankshaft, a piston, and a swing member. The crankshaft is housed in a crankcase in a direction such that a rotational center line is parallel to a vehicle-width direction. The piston is disposed above the crankshaft and reciprocates in an approximately up-down direction. The swing member is disposed forward of the crankshaft and the piston, coupled to the crankshaft by a coupling member, and swings in an approximately front-rear direction synchronized with a rotation of the crankshaft.