Abstract: A machine has two cylinders with respective pistons slidably supported therein, and has two crankshafts carrying counterweights operatively coupled to the respective pistons. A balance shaft carrying a balance weight is associated with and extends parallel to each crankshaft. The cylinders, crankshafts and balance shafts are parallel to and arranged in mirror-image fashion on opposite sides of a plane of symmetry. The crankshafts rotate synchronously in opposite directions, and each balance shaft rotates in an opposite direction from and at twice the speed of the associated crankshaft. In one embodiment the machine is an internal combustion engine and fuel is supplied to the cylinders through an eddy chamber which communicates with both cylinders through respective ducts. Two machines of the above type, an internal combustion engine and a compressor, can be operationally coupled, each crankshaft and balance shaft of the engine directly driving a respective crankshaft or balance shaft of the compressor.

Abstract: A single cylinder internal combustion engine has a piston which drives a crankshaft and flywheel through a connecting rod and has a counterweight arrangement which balances forces produced by the moving engine elements. The counterweight arrangement includes a weight on the crankshaft and two weights on the flywheel which fully balance the forces produced by rotating motion of the engine parts and partially balance the forces produced by reciprocal motion of the engine parts. Two balance shafts are provided which are parallel to and driven synchronously with the crankshaft. The balance shafts have respective first weights thereon which complete the balance of forces produced by the reciprocating motion of engine parts and have respective second weights thereon which balance the moment of the first weights with respect to the axis of the cylinder.

Abstract: An internal combustion engine comprising a flywheel mounted on a crankshaft and an aggregate housing which surrounds the flywheel and is mounted on the crank housing by vibration-damping buffer elements extending tangentially of the flywheel, which aggregate housing rotatably supports a drive shaft for an aggregate driven by the engine.