In-cylinder fuel injection device and internal combustion engine mounting the same

摘要

A fuel injection device directly injecting fuel into a cylinder is exposed to combustion flame and is heated to nearly 300 DEG C. Under such a temperature condition, deposits of carbonization-growing materials of the injected gasoline and a mixture of engine lubricant and the gasoline and soot produced from the deposits become attached onto the end portion of the fuel injection device. By preventing a change in the fuel injection characteristic with time by preventing of deposits and soot from attaching to the fuel injection device, an engine can be maintained in a normal combustion state for a long time. In order to attain this object, a cylindrical cover member with a bottom made of a high thermal conductive material is mechanically fixed to the end portion of the electromagnetic fuel injection valve through an insulator. The cover member is heated by combustion heat of the engine up to a temperature higher than a deposit producing temperature, and accordingly deposits which tend to attach onto the cover member are eliminated.