1. Field of the Invention
The invention is directed to an improved fuel injection system for an internal combustion engine.
2. Description of the Prior Art
One fuel injection system of the type with which the invention is concerned is known from German Patent DE 196 53 055 C1. This fuel injection system has a magnet valve for controlling the fuel injection. By means of the magnet valve, a communication of a work chamber of the fuel injection system with a relief chamber is controlled, and the magnet valve is open when without current, so that the work chamber communicates with the relief chamber and a high pressure for a fuel injection cannot build up in it. When current is supplied, the magnet valve closes, so that the work chamber is disconnected from the relief chamber, and high pressure builds up in it and a fuel injection takes place. The magnet valve is triggered by an electric control unit and has a magnet coil and a movable magnet armature. The magnet armature is connected to a valve member, by which the communication with the relief chamber is controlled. The magnet valve furthermore has a magnetic disk, by which the magnet armature is attracted when current flows through the magnet coil. A bolt is press-fitted into the magnet armature; it protrudes into a bore in the magnetic disk is and is guided displaceably therein. Thus the magnet armature is guided displaceably in the bore of the magnetic disk via the bolt, and the guidance of the magnet armature perpendicular to an end face, toward the magnet armature, of the magnetic disk must be accomplished with the greatest possible accuracy, in order to make it possible to dispose the magnet armature at the least possible spacing from the magnetic disk, without causing it to contact the magnetic disk. The structure of the magnet valve, with the bolt press-fitted into the magnet armature and with its guidance in the bore of the magnetic disk, is complicated and thus results in high costs.
USPTO Backgrounds
USPTO Backgrounds