Motor vehicle HT ignition coil - utilises two-state ferromagnetic wires for magnetic core of secondary winding, to improve performance at high engine speeds

摘要

The electromotive force produced by an ignition coil for a motor vehicle depends partly on the rate of change of flux in the primary winding. Several ferro-magnetic wires with two stable magnetic stakes are used to generate the wiegand effect and to improve the electromotive force at high engine speeds. A primary winding (1) is mounted on one arm (2) of a U-shaped magnetic circuit formed from several laminations (2a, 2b). This winding is powered via the ignition key (4) from the vehicle battery (5) and via the contact breaker (5). The other arm (6) of the magnetic circuit comprises several ferromagnetic wires. A secondary winding (7) is wound over them so that a high voltage is generated in the winding due to the change of magnetic state when the contact breaker creates a pulse in the primary winding.