PURPOSE: To promote combustion and prevent generation of soot at the same time in such a way that the convex part inside which faces a piston 12 in a cylinder head is formed by oxidizing catalyzer which generates heat by oxidizing reaction through contact with fuel.
CONSTITUTION: Four recess parts 6 are formed by oxidizing catalyzer 7 which contains rhodium as its main ingredient on the lower side of a cylinder head 4 at the position which faces the circumferential part of a piston recess 2, and an electric heat wire 8 is embedded in the catalyzer 7. By such a constitution, fuel flow which has been jetted through a fuel nozzle 5 is brought into ignition and combustion in the piston recess 2, and though part of the combustion gas flow is flowed into the cylinder head recess 6, unburned fuel in the inflow gas flow is ignited and burned by the recess part inside which is grown into high temperature, namely the ignition part of a self-exothermic plug.
AOYAMA TAROU
MIZUTA JIYUNICHI
