VALVE TIGHTENING STRUCTURE OF PISTON TYPE HIGH-PRESSURE PUMP

PROBLEM TO BE SOLVED: To provide a valve tightening structure of a piston type high-pressure pump capable of stably maintaining the tightened state of a high-pressure part even when a single cylinder pump vibrates by preventing a ring 35 uniformly assuring a high-pressure oil tightness from loosening by the tightening of a reed valve 8 in the circumferential direction. SOLUTION: To provide a ring-looseness preventing mechanism 36 increasing a frictional resistance installed between a ring 35 as a tightening member allowing the tightening operation of the reed valve 8 in the circumferential direction and a bracket 32, the ring 35 threadable into a pump housing 31 is provided so that the read valve 8 can be pressed against the pump housing 31 through a piston barrel 33, and the ring-looseness preventing mechanism 36 capable of preventing the ring 35 from loosening is installed between the ring 35 and the bracket 32.