Abstract: An ignition coil disposed and used in the neighborhood of a part made of a conductive material is provided with a first core made of a magnetic material, around which a primary coil and a secondary coil are wound; and a second core made of a magnetic material and having a cylindrical portion, in which the primary coil and the secondary coil and the first core are contained, and forms a closed magnetic path in conjunction with the first core.

Abstract: A distributor for an internal combustion engine, wherein a plurality of fixed electrodes which are respectively connected to a plurality of sparking plugs of an internal combustion engines, a rotating electrode rotatable in synchronism with a crank shaft of the internal combustion engine thereby forming sequentially a narrow gap with each of the fixed electrodes, and at least either the fixed electrodes or the rotatable electrode are made of such a ceramic that has the function of a varistor. Thereby the distributor is capable of suppressing noise current caused by spark discharge which is made between the rotating electrode and each of the fixed electrodes.

Abstract: An ignition distributor having a radio wave noise suppressing function has a rotor electrode and counter electrodes. At least the cathodic one of the rotor electrode and the counter electrodes is provided at its end with a coating layer of a material which is a mixture of a metal oxide having a high electric resistance and a metal oxide which constitutes a dielectric body stable in a high-temperature atmosphere. The metal oxide having high electric resistance consists essentially of 10 to 50 wt % of Cu.sub.2 O and 90 to 50 wt % of CuO, while the metal oxide constituting the dielectric body essentially consists of 70 to 90 wt % of alumina with respect to the weight of the metal oxide having high electric resistance.

Abstract: An ignition distributor for use in internal combustion engines has a noise preventive function capable of suppressing the generation of radiowave noises due to the spark discharge produced between a rotary electrode and stationary electrodes disposed on the side of the rotational circumference thereof opposing thereto. The ignition distributor has stationary electrodes and a rotary electrode, in which each of the plurality of stationary electrodes or rotary electrode has a main body made of a sintering product composed of powdery zinc oxide and powdery ferrite and a surface layer mainly composed of ferrite integrally formed to the surface portion of the main body.

Abstract: A distributor having electrodes made of a sintered body composed of a composite material such that the distributor can suppress radio noises to thereby prevent electric interference. The material for the electrodes, the sintered body, is composed of 45-90 mol % of zinc oxide and 55-10 mol % of ferrite, which can suppress radio noises generated between the electrodes due to spark discharging. At the same time, the energy loss within such composite material is small and consumption of electrode can be restrained. Electrode durability is further improved by including bismuth oxide, manganese oxide and cobalt oxide in the electrode material. An ignition plug and electric discharge machine can also advantageously use the electrodes composed of such materials.

Abstract: An ignition cable for supplying voltage to the spark plugs of an internal combustion engine, the cable having a low electrostatic capacity such that it does not produce noise in an FM radio frequency band. A central reinforcing string made of aramido-type fibers is covered by a ferrite core. A resistance wire having 8,000-14,000 turns/meter is wound onto the core. The assembly is then coated with a polyolefin insulation layer, a crossed-fiber reinforcement layer, and a silicon sheath, respectively.