HIGH-PRESSURE FUEL SUPPLY PUMP

摘要

The purpose of the present invention is to provide: a relief valve structure which consistently exhibits high fuel release characteristics; and a high-pressure fuel supply pump in which the relief valve structure is mounted, the relief valve structure and the high-pressure fuel supply pump having a compact and inexpensive structure. This high-pressure fuel supply pump is configured such that: a suction passage, a pressurizing chamber, and a discharge passage are formed in this order from the upstream side in a body; a discharge valve for limiting the direction of flow of fuel is disposed in the discharge passage; and a relief valve is disposed in a relief passage formed between the upstream side of the discharge valve and the downstream side of the discharge valve. The high-pressure fuel supply pump is characterized in that the relief valve has: a seat section for sealing fuel by the contact of a valve body with a valve seat section; a fluid passage formed as a fluid throttle in a part of the valve body; a guide section formed integrally with the valve body; and a cylindrical wall section for slidably holding the guide section and preventing the valve body from being decentered radially.