Ignition coil with counter magnetic field

摘要

An ignition coil having a transformer surrounding a cylindrical magnetic core. The transformer has a primary coil, to which a DC potential is applied in bursts and which generates a primary magnetic field, and a secondary coil, which retrieves induced electromotive force. An outer cylinder, surrounding the transformer, is also provided. At at least one end of the ignition coil at least one toroidal magnet is located. The inside and outside perimeters of the toroidal magnets have polarities which are opposite to each other. When a plurality of magnets is provided, they are nested inside one another between the magnetic core and the outer cylinder. The direction of the reverse biasing magnetic field generated by the magnet(s) is opposite to that of primary magnetic field generated by the primary coil. The foregoing construction provides a compact ignition coil which is efficient in operation and is capable of making effective use of the induced electromotive force generated. <IMAGE>