Switching system for lights of model railway vehicles - uses arm with magnet operated by axle and acting on reed switch

摘要

The switching system is for changing over the lighting circuit when the direction of the train movement is reversed. A bush (2) is a light friction fit on one axle (4) of the carriage or vehicle. The bush is provided with an arm (1) which carries a permanent magnet (8). Fixed to the carriage chassis is a reed switch (5) wired into the circuit for the exterior lamps (9,10). When the axle turns the bush and arm are carried with it to one extreme stop position or the other, depending upon the direction of rotation of the axle. In one position the magnet is close to the reed switch and causes its contacts to change over and light the appropriate lamps (9). In the other position, the magnet is away from the switch and the contacts return to the normal state, closing the circuit to the lamps at the other end (10). Only a slight friction effect is required to turn the bush. This can be provided by a coil spring (3) bearing against a wheel and a shoulder on the bush, or by friction between bush and shaft.