Abstract: A belt tensioner has a shaft having an oil reservoir in a lower portion thereof and having an external thread and rotatably mounted in a body, a torsion spring provided between the body and the shaft so as to urge the shaft in a rotational direction, and a cylindrical rod having an internal thread engaged with the external thread of the shaft. A lower end of the rod being projected from the body so as to be operatively connected to a tension pulley for a belt. The torsion spring and both the threads are arranged to project rod by the rotation of the shaft urged by the torsion spring. An oil passage is provided in the shaft so as to communicate the oil reservoir with the bore above the internal thread of the rod.

Abstract: An internal combustion engine combustion process in which fuel injected from an injection nozzle takes the form of liquid droplets distributed in a combustion chamber so that a slow burning of the combustion at relatively low maximum combustion temperature is achieved. An exhaust system of the engine has a section which acts as a heat insulator. This construction provides a proper environment for oxidation of exhaust gases.