GB446228A - Improvements in and relating to electric battery charging systems - Google Patents

Abstract

446,228. Charging batteries ; automatic control systems. FORD MOTOR CO., Ltd., 88, Regent Street, London. July 11, 1935, No. 19810. Convention date, Oct. 29, 1934. [Class 38 (iv)] Relates to battery-charging systems including a battery 23, an electric generator 10 adapted to supply current at two different rates, a charging rate regulator 25 with vibrating arm 26, a cut-out 16 and thermally responsive means 34, 36 for varying the charging voltage in accordance with temperature changes. The generator 10 is provided with a shunt field winding 11 which is directly earthed by the opening arm 26 of the regulator 25 to give the high charging rate and is earthed intermittently through resistances 14, 15 to give the low charging rate as the arm 26 vibrates. As the generator 10 speeds up, the points 18, 19 of the out out are opened by the voltage winding 20 and the battery 23 is charged at the high rate through the cut out current winding 21 and the regulator winding 30 which tends to open the points 27, 39. Such opening of the points does not take place until current also flows through the winding 28 on the battery becoming fully charged and the charging voltage attaining a value corresponding to atmospheric temperature. The thermally responsive means comprise two bi-metallic arms 36, 34 insulated from one another and carrying co-operating contacts, the upper arm 36 having a heating winding 40 which renders it responsive to generator voltage, while the lower arm 34 responds only to atmospheric temperature. When the battery is fully charged and the voltage rises to the value corresponding to the temperature, the points on the arms 34, 36 close and current flows through the winding 28 of the regulator ; the points 27, 39 then open so that the generator field 11 is grounded through winding 15 and the charging rate is reduced. Winding 15 is opposed to windings 28, 30 so that arm 26 vibrates. Vibration of the bi-metallic arm 36 is checked by a heating winding 37 thereon in series with winding 28. When sufficient lights 22 are switched on, the current through winding 30 is reduced or may even be reversed and the charging takes place at the high rate whatever the condition of the battery.