Abstract: An electro-magnetic valve having a very fast response and a favorable temperature-gradient characteristic. The valve includes an iron core which carries a stationary magnetic winding within a valve housing, and a plunger coaxially oriented relative to the iron core and separated from the core by an air gap. The magnetic winding is made of a metal having a specific resistance greater than 20 milli-ohms per square millimeter of cross-sectional area per meter length at 20 degrees centigrade. The valve may also include a temperature compensating resistor connected in series with the magnetic winding.

Abstract: An electromagnetic fuel injection valve in which a valve needle coupled to the armature has twisting channels for carrying fuel and for creating turbulence therein. The channels terminate in a pressure chamber whose volume is chosen to be equal to or smaller than the volume of fuel injected in a single stroke.

Abstract: An electro-magnetically actuated solenoid valve is provided with two opposing valve seats between which the armature moves axially. The armature loosely holds valve closure members which cooperate with the opposing valve seats. The valve closure members are urged apart by a spring, and the combined force of this spring and of two further springs exhibits an abrupt change which stabilizes the armature in a position approximately mid-way between the two extreme positions.The end portion of the armature and of the cooperating pole piece is so configured that the path of the armature is limited to a region within which the magnetic force does not change rapidly.

Abstract: An electromagnetic 3-way valve arrangement having two valves, each controlled by a separate armature of a single coil solenoid, is described. The top end of each armature has a self-aligning closing element, and the two armatures are held apart by springs acting against an intermediate member, which also contains the valve seat for the lower armature. When deenergized, these springs act against the armatures to close the upper valve and open the lower valve. When the solenoid coil is partially energized, it moves the lower armature upward to close the lower valve also. When the solenoid coil is fully energized, it moves the upper armature downward to open the upper valve. If desired, the armature can be disposed within the solenoid so that the upper armature is operated at partial energization, and the lower armature at full energization of the solenoid coil.