Patent GB-394345-A (GB)
Title: Improvements in or relating to illumination control system
IPC: H05B37/02
Filed: 1931-12-11
Abstract: 394,345. Control systems for consuming devices. IGRANIC ELECTRIC CO., Ltd., 147, Queen Victoria Street, London.-(Assignees of Hunter, R. B.; Shorewood, Wisconsin, U.S.A.) Dec. 11, 1931, No. 34400. Convention date, Dec. 12, 1930. Addition to 386,378. [Class 38 (iv).] An illumination control system for a set of lamp circuits 10 comprises means in the form of sending rheostats 1 for individually presetting different current intensities in each lamp circuit, and common intensity control means 30, 31, 32, in response to the selective operation of which the current intensities in the respective circuits may be gradually changed from one setting to others. The position of each individual presetting element 1a on its sending rheostat determines its potential and upon operation of the common intensity control means a corresponding following element 4a is driven over a receiving rheostat 4 until its potential is equal to that of the element 1a. Each following element actuates a dimmer rheostat 14 in the lamp circuit. Additional individual preselecting elements 51 may be provided for the respective lamp circuits, together with respective individual intensity control conductors 8 whereby the current intensity in any desired circuit may be brought gradually to any preselected valve by actuation of the same mechanism. A number of common preselecting elements 52 .. 55 and joint intensity control elements 56 .. 59 may be provided whereby the current intensity in selected lamp circuits may be gradually and jointly brought to that determined by the setting of the respective element 52. The contactors 8 are arranged to associate the following elements 4a of selected lamp circuits with desired elements 52 .. 55. Continuity control elements are provided for determining the energization or complete de-energization of the individual lamp circuits. These may comprise individual control elements 22 .. 25 and one or more joint continuity control elements 26 .. 29 whereby the lamp circuits may be separately or jointly energized or deenergized. The separate positions of the individual elements 22 determine respectively individual control or joint control by one or other of the elements 26 .. 29. The elements 22 .. 29 control contactors 18 in the respective lamp circuits. Independent means 48 effect at will a gradual reduction of current in all lamp circuits and further independent means 50 also operable at will prevent increase of current in any lamp circuit. The means for operating each of the respective following elements 4a comprise a continuously rotating pinion 42 selectively engaged with racks in a member 41 by electromagnets 34, 44, the member 41 being coupled to the element 4a. The magnets 34, 44 are selectively energized according to the direction of current flow between the preselecting element in operation and the following element 4a by a polarized relay 6. The means 48, 50 control contactors which interrupt the circuits of the magnets 34, 44 respectively. The pinions 42 may be individually or jointly driven as by a motor 43 which may have rheostat 43b for speed variation.