TRAFFIC LIGHT TWO-FILAMENT LAMP SWITCHING DEVICE Russian patent published in 2000 - IPC

FIELD: railway transport; automatic and signalling facilities; train movement interval control devices. SUBSTANCE: device has ac source connected by one pole with two-filament lamp base, ballast resistor and switch elements, stabilizing diodes, integrating capacitors, current switches and current resistor. Switch elements are built around transistors of different conductivity. Current switches are built around field-effect transistors of different conductivity. One of current resistor terminals is connected tom main filament of lamp and to one of terminals of limiting resistor whose other terminal is connected to bases of switch element transistors. Other terminal of current resistor is connected with common pole of ac source, field-effect transistor sources, emitters of transistors and integrating capacitors. Other terminals of integrating capacitors are connected to field-effect transistor control gates. Drains of field-effect transistors are connected to lamp reserve filament. EFFECT: improved reliability in operation. 1 dwg