To provide a piston type high pressure pump capable of being low in a cost, high in reliability, and improving seal performance by coping with increase in a discharge pressure.
The piston type high pressure pump is emphasized that sealing is effected at three stages of the high pressure part of a pump chamber 29, the suction pressure part situated upper stream from a suction valve 22, and a low pressure part where leak through the periphery of a piston 3 occurs; and the suction pressure part is introduced to the periphery of a piston 3. The piston type high pressure pump comprises a first seal mechanism 45 to seal a gap between the high pressure part of the pump chamber 29, communicating with the suction valve 22 and a discharge valve 23, and a suction pressure part situated in upper stream from the suction valve 22; and a second seal mechanism 46 to seal a space between the suction pressure part and the low pressure part leaking from the periphery of the piston 3.
HOZUMI ETSURO
YAMAZAKI AKINORI
KASAHARA KAZUMASA
