The cylinder head is a valve mechanism in an internal combustion engine. It is mainly used to close the upper part of the cylinder to form the combustion chamber. It also serves as a support for the camshaft, rocker arm shaft and intake and exhaust pipes. It is mainly used to suck air into the inside of the cylinder, and the spark plug The combustible mixed gas is ignited, driving the piston to do work, and the exhaust gas is discharged from the exhaust pipe.