GB599873A - Improvements in vehicle-carried electric lighting systems - Google Patents

Abstract

599,873. Self-contained supply systems. MANDL, A., and METROPOLITANVICKERS ELECTRICAL CO., Ltd. Sept. 24, 1945, No. 24720. [Class 38 (iv)] Variable speed generators, with.-In a vehicle lighting system in which a variable speed alternator, e.g. an axle-driven inductor alternator, supplies a lighting circuit and also charges a battery which, at low vehicle speeds or standstill, supplies the same lighting circuit, one alternator output winding charges the battery while another winding or a tapped portion of the same winding supplies the lighting circuit at a lower voltage, substantially equal to the battery discharge voltage. In Fig. 2, the alternator output winding 1 charges, through rectifier 4, the battery 3 which can supply lamps 5 through contactor switch 8, while winding 2 (or alternatively a tapped portion of winding 1) can supply the lamps through contactor 7 and rectifier 6. The contactors may respond to vehicle speed, contactor 7 being closed only at speeds above a certain value ; contactor 8 may, however, operate on a fall of the battery charging current below a certain value. To avoid lamp flicker, the one contactor may close before the other opens. The alternator field winding 10 (which may alternatively be supplied directly by the battery) is shown connected across rectifier 6 in series with the automatic voltage regulator 9 which may be of the carbon pile type. For accelerating the decrease of charging current as the battery charge increases, there may be a saturable reactor 11 in series with the winding 1 and having a saturating winding 13 connected across the shunt 14 in the battery-charging circuit, with or without an opposing winding supplied at constant voltage through rectifier 6. In a modification, contactor 7 closes (when contactor 8 is open) to connect the lamps directly across the winding 2 for supply with A.C.