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 (β−α) from the first angle.

A modular internal combustion engine (10) comprising a cam crank assembly (75) having a cam crank (74), an intake cam (90) and an exhaust cam (92), the cam crank (74) having a piston stroke guide pattern (76) to control the stroke motion profile of the piston (70), which can be expanded by replacing the crank shaft (22) with a longer crank shaft (22), and installing a supplemental engine block (18) with a supplemental cam crank assembly (75).

A piston internal combustion engine with generator has two cylinders and cylinder heads and pistons with connecting rods and two crankshafts which are connected by gears with a ratio of 1:−1 (with opposite direction of rotation). The first crankshaft with the gear is mounted parallel to the second crankshaft with the second gear in one engine case such, that the gears engage. The first crankshaft is coupled to the first generator rotor and the second crankshaft is coupled to the second generator rotor or the flywheel. The moment of inertia of the first crankshaft assembly with the first gear and the first generator rotor is equal to the moment of inertia of the second crankshaft assembly with the second gear and the second generator rotor or flywheel. The cylinders with the pistons and are positioned perpendicularly to the plane of symmetry between the crankshafts, with the axes of the pair of cylinders lying in a plane with the both pistons being at the top dead center simultaneously.

A power unit for a hybrid vehicle is provided with a twin-cylinder reciprocating piston engine, which has two pistons which are guided in two cylinders in tandem arrangement. Two counter-directional crankshafts are connected with the pistons by connecting rods. At least one generator is rotatable co-directionally to the first crankshaft and counter-directionally to the second crankshaft. A camshaft with valve cams are operatively connected with control valves. A flywheel mass element is arranged on the second crankshaft or on a flywheel mass compensating shaft, and a compensating camshaft are provided. The compensating camshaft includes at least one compensating cam element which is operatively connected with a linearly guided compensating mass.

An in-cylinder pressure sensor system and a pressure sensor adaptor that allows for the inclusion of a pressure sensor to monitor the pressure of an engine cylinder is provided. The pressure sensor adaptor includes a first end, a second end, a threaded section, a cylindrical midsection, and an annular section; and a pressure sensor channel that comprises an opening in the first end and an opening in a second end and spans from the first end to the second end through the threaded section, the cylindrical midsection, and the annular section. The pressure sensor may be housed in the pressure sensor channel of the pressure sensor adaptor.

A modular internal combustion engine (10) comprising a cam crank (74) having a piston stroke guide pattern (76) to control the stroke motion profile of the piston (70), which can be expanded by replacing the crank shaft (22) with a longer crank shaft (22), and installing a supplemental engine block (18) with a supplemental cam crank assembly (75).

An in-cylinder pressure sensor system and a pressure sensor adaptor that allows for the inclusion of a pressure sensor to monitor the pressure of an engine cylinder is provided. The pressure sensor adaptor includes a first end, a second end, a threaded section, a cylindrical midsection, and an annular section; and a pressure sensor channel that comprises an opening in the first end and an opening in a second end and spans from the first end to the second end through the threaded section, the cylindrical midsection, and the annular section. The pressure sensor may be housed in the pressure sensor channel of the pressure sensor adaptor.

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.

The invention relates to a generator set, in particular a generator set of a hybrid vehicle, with a two-cylinder piston engine (1), which has a crankshaft housing (10), in which two counter-rotating crankshafts (11, 12) are arranged, which are connected by means of piston rods (13) to pistons (18, 19), which are guided inside two cylinders (21, 22) in a tandem arrangement, wherein at least one crankshaft (11, 12) is drivingly connected to a generator (41, 42), and wherein the piston engine (1) comprises a cylinder head (20), which is connected to the crankshaft housing (10), wherein the piston engine (1) has a lower-mounted camshaft (30), and the cylinder head (20) can be connected to the crankshaft housing (10) in at least two positions, in particular positions rotated through 180 relative to each other. Furthermore, the invention relates to a vehicle with such a generator set.

A piston internal combustion engine with generator has two cylinders and cylinder heads and pistons with connecting rods and two crankshafts which are connected by gears with a ratio of 1:1 (with opposite direction of rotation). The first crankshaft with the gear is mounted parallel to the second crankshaft with the second gear in one engine case such, that the gears engage. The first crankshaft is coupled to the first generator rotor and the second crankshaft is coupled to the second generator rotor or the flywheel. The moment of inertia of the first crankshaft assembly with the first gear and the first generator rotor is equal to the moment of inertia of the second crankshaft assembly with the second gear and the second generator rotor or flywheel. The cylinders with the pistons and are positioned perpendicularly to the plane of symmetry between the crankshafts, with the axes of the pair of cylinders lying in a plane with the both pistons being at the top dead center simultaneously.