Spontaneous-combustion engine

摘要

A diesel engine wherein the crown of the piston has a flat end face provided with a centrally located circular combustion chamber and with an annular recess which surrounds and communicates with the combustion chamber and receives the tip of the fuel injection nozzle when the piston completes its compression stroke. At such time, the nozzle is close to but is still of contact with the piston. The tappets of first and second valves, which are installed in the head of the cylinder and respectively serve to admit air into and to permit evacuation of combustion products from the combustion chamber, overlap the end face of the piston to such an extent that they cannot bend the shafts of the respective valves if and when engaged and shifted axially by the piston during movement of the latter toward the top center of its compression stroke.