Magnetic signal generator for electronic ignition system - employing ferromagnetic rotor passing between permanent magnet and hall element

摘要

The signal generator is principally intended for installation in the distributor for an i.c. engine ignition system. It replaces the contact breaker. A yoke (7) of magnetic material has a flange at each end (8,9), one carrying a permanent magnet (2) and the other a Hall element (3). The yoke is fastened to a mounting plate in the distributor housing. The rotor (1) consists of a strip to magnetic material (4) bent to form flanges at each end (5,6). Yoke flanges and rotor flanges lie on concentric circles. There is an air gap between the rotor flanges and the permanent magnet and Hall element. The rotor is attached to the distributor spindle (10) of non-magnetic material. As it rotates the flux circuit between permanent magnet and Hall element is alternately made and broken causing the latter to give a pulse output for controlling the electronic ignition system. The yoke mounting is typically rotatable through an arc by a conventional advance and retard mechanism.