PURPOSE: To improve the fuel injection characteristics of a fuel injection valve while lowering the machining accuracy for the component parts of the valve and simplifying the shape of the component parts, by fixing an armature and a valve body together in a unitary manner, and shaping either of the head of the valve body or a seat surface to have a spherical surface.
CONSTITUTION: A valve body 31 is disposed in a valve housing 28 which is fixed to the top of a main case 19 of a fuel injection valve 43 by the intermediary of a spacer 26 functioning also as a bearing and a sealing O-ring 27, with its shaft portion 32 being extended through a bearing hole 33 formed in the spacer 26 and projected to the side of a solenoid coil 20, in the manner that the axial movement of the valve body 31 is restrited by the end face of the spacer 26 and a conical sealing surface 30 formed around a fuel injection port 29 to correspond to the valve lift. Here, arrangement is such that the head 37 of the valve body 31 is shaped in a spherical form and a proper clearance is provided between the shaft portion 32 of the valve body 31 and the bearing hole 33 of the spacer 26. Therefore, it is enabled to obtain a good sealing performance even if the axis of the shaft portion 32 of the valve body 31 is not aligned correctly with the axis of the sealing surface 30 of the injection port 29.
MAKIMURA TOSHIROU
WATANABE YUKIHIRO
Next Patent: ELECTROMAGNETIC FUEL INJECTION VALVE