Patents Examined by D. Deal
  • Patent number: 6032879
    Abstract: When an electromagnetic coil receives an electric supply, a stationary core, a yoke, and a movable core form a magnetic circuit. The movable core is attracted to a side of the stationary core against the force provided by a return spring member. A fuel passage for injection of fuel is then opened. Axial direction stepwise differences are formed on the movable core. One end face of the stationary core opposes the stepwise difference through a first gap. A projection portion of the yoke is provided toward an inner side of the yoke. This projection portion opposes a position of a side to provide an axial direction magnetic attraction through a second gap. By the provision of the first and second gaps, plural axial direction magnetic attraction gaps are formed and become a part of the magnetic circuit. By increasing a magnetic attraction efficiency of the movable core, an improvement in performance of a fuel injector and a fuel injector having a compact size and a light weight structure can be attained.
    Type: Grant
    Filed: January 16, 1998
    Date of Patent: March 7, 2000
    Assignees: Hitachi, Ltd., Hitachi Car Engineering Co., Ltd.
    Inventors: Yasunaga Hamada, Hideo Tatsumi, Kenichi Gunji, Yukihiro Yoshinari