Patent ID: 6532927
Filing Date: 2003-03-18
Classification: F01L,F02B

Abstract:
An internal combustion engine comprising a cylinder block defining at least one cylinder bore, a piston reciprocating in the cylinder bore, a cylinder head member closing one end of the cylinder bore and defining a combustion chamber with the cylinder bore and the piston, an intake passage having an intake port through which air is introduced into the combustion chamber, an intake valve arranged to open and close the intake port, an exhaust passage having an exhaust port through which exhaust products are discharged from the combustion chamber, an exhaust valve arranged to open and close the exhaust port, at least one camshaft arranged for rotation and having cam lobes to activate at least one of the intake valve and the exhaust valve, the camshaft defining an aperture extending therethrough and being positioned next to at least one of the cam lobes, the aperture extending generally normal to an axis of the camshaft, and a decompression mechanism configured to decompress the combustion chamber for starting of the engine, the decompression mechanism including a shaft extending through the aperture, an actuator affixed to the shaft for pivotal movement about an axis of the shaft, the actuator having a first section arranged to hold at least one of the intake valve and the exhaust valve in an open position when the actuator exists in an initial position, and a second section arranged to initially retain the actuator in the initial position and to release the actuator from the initial position when the camshaft rotates, the shaft being rigidly supported by an inner surface of the aperture, and a space extending radially between at least a portion of an outer surface of the shaft and at least a portion of the inner surface of the aperture.