Crankcase air valve structure and air compressor

A crankcase air valve structure, comprising an air intake valve and a valve seat plate which are sequentially mounted on an end surface of a crankcase, wherein

• the valve seat plate is provided with at least one group of air intake holes;
• the air intake valve is provided with at least one valve plate, each of the at least one valve plate having root portions located at two ends thereof and lug portions located between the two ends, and each of the at least one valve plate being connected to a valve body of the air intake valve via the root portions;
• wherein the crankcase air valve structure further comprises sidestep grooves and accommodating recesses which are in communication with a gas channel of the crankcase are provided in the end surface of the crankcase;
• wherein, in a non-air intake state, each of the at least one valve plate covers a corresponding group of air intake holes;
• and
• wherein, in an air intake state, the lug portions abut against corresponding accommodating recesses, and the root portions are bent toward corresponding sidestep grooves.