Diesel engine valve mechanism

The invention discloses a diesel engine valve timing mechanism which comprises an air inlet system and an exhaust system, the air inlet system is arranged between a cam shaft and an air inlet valve, the air inlet system comprises an air inlet tappet assembly, an air inlet rocker arm, an air inlet rocker arm shaft, a rocker arm shaft seat and a screw, the cam shaft drives the air inlet tappet assembly, the air inlet tappet assembly drives the air inlet rocker arm to work, and the exhaust system drives the air inlet rocker arm to work. The air inlet rocker arm transmits torque to an air inlet valve with an air inlet rocker arm shaft as a fulcrum, and the air inlet rocker arm shaft is fixed through a first rocker arm shaft seat and a screw. The invention aims to solve the problem of tense layout of the cylinder cover in the background technology, designs the gas distribution mechanism into a horizontal double-rotating-shaft rocker arm type, reduces the height of the rocker arm mechanism, improves the space utili