Clamp for machining of positioning pin hole of cylinder cover of engine

The utility model discloses a clamp for machining of a positioning pin hole of a cylinder cover of an engine. The clamp for machining of the positioning pin hole of the cylinder cover of the engine comprises a base, wherein a positioning mechanism and a clamping mechanism are arranged on the base, the positioning mechanism comprises a positioning claw which can be installed in an air inlet valve seat mouth of the cylinder cover in a clamped mode and an expansion mechanism which can be installed in an air channel mouth of the cylinder cover in a clamped mode, and the clamping mechanism comprises a pressing claw which can be installed on the top surface of the cylinder cover in a pressed mode so as to tightly press the cylinder cover onto the base. According to the clamp for machining of the positioning pin hole of the cylinder cover of the engine, the air inlet channel valve seat mouth, with the highest workblank precision, of the cylinder cover and an exhaust channel mouth, with the highest workblank precision, of the cylinder cover are used for positioning for machining of the positioning pin hole, the positioning precision is high, machining deviation, caused by nonuniformity of workblanks is avoided, allowance distribution for machining in the subsequent stages is guaranteed, and hidden dangers such as water leakage or gas leakage caused by thin wall of the inner cavity of the cylinder cover are avoided. The clamp for machining of the positioning pin hole of the cylinder cover of the engine is simple in structure and fast and convenient to operate, the clamping way is effective, and thus the machining precision of the positioning pin hole of the cylinder cover is effectively guaranteed.