To provide a fuel injector of an electronic controlling type for automobiles which is more resistant to chattering, though fuels with inferior lubrication characteristic, such as alcohol, compressed natural gas and the like are used.
This fuel injector is provided with a plunger 2 slidably inserted into a cylinder 8a and having a ball valve 2a on a tip thereof, a flange portion 2c having a clearance between itself and the tip portion of a cylinder 8a formed around the periphery of the medial portion of the plunger 2, a spring 3 energized so as to urge plunger 2 within the cylinder 8, and a nozzle body 4 having a fuel injecting orifice 4b to be opened and closed by the ball valve 2a, wherein the plunger 2 is reciprocated through urging action of the spring 3 and pulling back action of the electromagnetic coil 6 with a stroke which is naturally defined because the tip surface 8c of the cylinder 8a should be bumped to the flange portion 2d. Thus, lubricating oil is filled in a chamber 13 formed to seal sliding and bumping portions between the plunger 2 and the cylinder 8a, and the interiors of the chamber 13 and cylinder 8a is employed as the fuel injector separated from the flow path 5e of pressurized fuel and directed to the nozzle body 4.
BABA NOBORU
KOSUGE TOKUO
OIKAWA HIDEJI
TERAKADO KAZUYOSHI
TERANISHI TAKAO
SOMA MASAHIRO
HITACHI CAR ENG CO LTD