A compression ignition internal combustion engine (1), which includes a cylinder (2), a piston (3) reciprocably received within the cylinder (2), a pair of contra-rotating crankshafts (4, 5) rotatably mounted relative to the cylinder (2), a pair of connecting rods (6, 7) each having a first end (61, 71) connected to a crank journal (41, 51) of a respective one of the crankshafts (4, 5) and a second end (62, 72) connected to the piston (3). The engine (1) is configured such that the stroke of the piston (3) in a first direction toward the crankshafts (4, 5) causes each crankshaft (4, 5) to rotate by a first angle and the piston stroke in a second direction opposite the first direction causes each crankshaft (4,5) to rotate by a second angle different () from the first angle.

A compact and efficient Z-twin internal combustion engine is described herein. The Z-twin internal combustion engine comprises horizontally opposed cylinder arrangement that allows for vibration cancellation. The Z-twin engine comprises a central shared cam that drives angled side valves of both the opposing cylinders, thereby greatly reducing moving parts and thus provides a significantly more efficient angled valve approach.

A drive unit is situated between a first wheel axle and a second wheel axle and has an internal-combustion engine with a crankshaft system including a horizontally oriented crankshaft, which crankshaft acts upon a continuously variable transmission system which drives wheels of the first wheel axle and of the second wheel axle. The crankshaft is caused to rotate by at least one piston of the engine. The crankshaft interacts with a first set of V-pulleys of the transmission system, which first set of V-pulleys, by way of a first drive shaft, is connected with a first differential of the first wheel axle. The first set of V-pulleys, by way of an endless member, is in an operative connection with a set of V-pulleys which, with the interposition of a second drive shaft, influences a second differential of the second wheel axle.

A balanced rotary engine for applying torque to a drive shaft. The engine has an outer casing with a main drive case. A cylinder is rotably mounted in the casing and a piston is mounted to move longitudinally within the cylinder. Two connecting arms, each with a connecting end, one of the ends is connected to the piston, and two crankshafts, each one being rotably connected to the other connecting end of the connecting arms. Two drive wheels are contra-rotably connected to the respective first and second crankshafts. A fixed drive ring has a circumferentially disposed drive member surface. The fixed drive ring is mounted in the case so that the drive member surface faces the piston. The two drive wheels mesh with the drive ring.

An engine cylinder block includes a cylinder block housing and a double-crankshaft mechanism installation case located at a downside of the cylinder block housing. The cylinder block housing is integrally connected with the double-crankshaft mechanism installation case. The cylinder block housing is provided with a cylinder block cavity. The double-crankshaft mechanism installation case is enclosed and formed by an end cover and a side cover. A piston rod guiding groove is installed in the double-crankshaft mechanism installation case. A connecting rod sliding groove is configured through the piston rod guiding groove. A crank operation cavity is configured on both sides of the piston rod guiding groove. A main spindle installation hole is configured on the shell at both ends of each crank operation cavity. A main spindle supporting portion is configured below the main spindle installation hole.

A motor vehicle includes a motor and a transmission including a drive shaft driven by the motor and connecting the motor to the transmission, a first output shaft extending along the vehicle longitudinal axis in the one direction, which first output shaft is connected to a wheel axle by a first differential, and a second output shaft extending along the vehicle longitudinal axis in the opposite direction, which second output shaft is connected to a second wheel axle by a second differential, characterized in that the drive shaft is disposed in the longitudinal axis of the motor vehicle and the first and the second output shaft are disposed on opposing sides relative to the longitudinal axis of the motor vehicle with identical spacing with respect to the longitudinal axis of the motor vehicle.

The invention relates to a constant-volume combustion engine (10; 110; 210), in particular a reciprocating engine for generating mechanical energy by the expansion of a gas or a hot gas from the combustion of a gas mixture or gas-fuel mixture, having at least one piston/cylinder unit, the piston (14; 114; 214) of which is connected to a piston rod (20; 120; 220), wherein said piston rod (20; 120; 220) is drivingly connected to at least two crankshafts (30, 40; 130, 140; 230a, 230b, 240), the first crankshaft (40; 140; 240) being mounted, such that it can rotate eccentrically, on the second crankshaft (30; 130; 230a, 230b), which is parallel thereto and is rotationally coupled thereto.

A pivoting bearing is provided for two connecting rods in a reciprocating piston of an internal combustion engine having two crankshafts which are driven via the reciprocating piston and the connecting rods. The pivoting bearing is received by piston bores of the piston and has gudgeon pin bores for mounting gudgeon pins for gudgeon pin eyes of the connecting rods. The pivoting bearing has radial bearing regions which are provided with the pin bores, are arranged on both sides of a center longitudinal axis of the reciprocating pistons, and delimit the gudgeon pin eyes in a manner which forms an intermediate space. To optimize the pivoting bearing, the bearing regions of the pivoting bearing are configured as cylinder bodies with a cup-like cross section, of which each cylinder body has a base wall and a bearing ring shell. The base walls of the two cylinder bodies extend at a spacing from one another, and the bearing ring shells which surround the base walls are guided away from the base walls in opposite directions. A plurality of connecting stubs run between the base walls in such a way that two connecting stubs are arranged on a side of the pivoting bearing, which side faces a piston crown, and extend at a relatively small spacing from ring sections of the gudgeon pin eyes, and in such a way that the connecting stubs and the ring sections have lubricating structures for lubricating connecting rod bearings of the connecting rods.

An engine cylinder block includes a cylinder block housing and a double-crankshaft mechanism installation case located at a downside of the cylinder block housing. The cylinder block housing is integrally connected with the double-crankshaft mechanism installation case. The cylinder block housing is provided with a cylinder block cavity. The double-crankshaft mechanism installation case is enclosed and formed by an end cover and a side cover. A piston rod guiding groove is installed in the double-crankshaft mechanism installation case. A connecting rod sliding groove is configured through the piston rod guiding groove. A crank operation cavity is configured on both sides of the piston rod guiding groove. A main spindle installation hole is configured on the shell at both ends of each crank operation cavity. A main spindle supporting portion is configured below the main spindle installation hole.

A fan is suitable for an air-guiding system of an outboard motor including an internal combustion engine and a covering hood bounding an engine interior space. The engine drives the fan, which is connected to an upright shaft journal projecting beyond an upper side of a housing of the engine. The covering hood has air flow openings, and the fan influences the air flows in the covering hood interior space. A flywheel, fixedly attached to the upright shaft journal, carries a fan wheel of the fan. The fan wheel is set in place from above, and the flywheel carries the fan wheel for conjoint rotation. Airflows enter the interior space via an inlet opening and a first conducting device, and the airflows, under the action of the fan, act upon at least parts of surfaces of the internal combustion engine and the auxiliary units to cool the internal combustion engine.