Hitachi Astemo Ltd.

Keihin Corporation

Yasuhiko Nabeshima

Shou Kanda

Kento Yoshida

Junichi Miyashita

Takahiro Yasuda

Masateru Moriya

Nozomu Sasaki

Kousaku Yotoriyama

An electromagnetic fuel injection valve includes: a valve body having a rod connected to a valve part; a movable core fitted onto the rod slidably between valve-open side and valve-closed side stoppers; a fixed core having an attracting face opposing the movable core; a valve spring urging the valve body in a valve-closing direction; and an auxiliary spring exhibiting a spring force that urges the movable core to separate from the valve-open side stopper and abut against the valve-closed side stopper when a coil is unenergized. A first curved face part is protruded from a surface, opposing the movable core, of the fixed core, and a second curved face part is provided in an outer peripheral part of a surface, opposing the movable core, of the valve-open side stopper, the first and second curved face parts each having an arcuate cross-section and being capable of abutting against the movable core.

Electromagnetic fuel injection valve

An electromagnetic fuel injection valve includes: a valve body having a rod connected to a valve part; a movable core fitted onto the rod slidably between valve-open side and valve-closed side stoppers; a fixed core having an attracting face opposing the movable core; a valve spring urging the valve body in a valve-closing direction; and an auxiliary spring exhibiting a spring force making the movable core abut against the valve-closed side stopper when a coil is unenergized. A surface, opposing the movable core, of the valve-closed side stopper includes: an annular first curved face part curved convexly toward the movable core and capable of abutting thereagainst; and first and second taper faces continuous respectively to inner and outer peripheral sides of the first curved face part and gradually separated from the movable core in going radially inward and outward, respectively, from the first curved face part.

An electromagnetic fuel injection valve wherein a movable core disposed opposing an attracting face of a fixed core is slidably fitted onto a stem forming a valve body together with a valve part operating in cooperation with a valve seat, a valve-open side stopper is fixed to the stem so that, by making the movable core, that is attracted to the face when energizing a coil, abut against this stopper, the body is operated to open, and a valve-closed side stopper is fixed to the stem further on the seat side than the other stopper so as to restrict a stroke of the movable core between these stoppers. At least an end part of one of the valve-closed side stopper and the movable core, the end part being on a side of the other one thereof, is formed to gradually decreasing its cross-sectional area in going toward the other one.

Growing community of inventors

Tochigi, Japan

Yasuhiko Nabeshima