| 摘要 |
356,165. Exchange systems. LOOG, C., 10, Berlinerstrasse, Wilmersdorf, Berlin. June 2, 1930, No. 17064. Convention date, Jan. 28. [Class 40 (iv).] Telephone exchange batteries are charged as required during use, the charging current being automatically regulated in stages by a series of relays which operate in accordance with variations in the load. In the arrangement shown, relays 1 .. 7 have main (lower) windings connected in series with the load 53 and secondary (upper) windings in parallel across the battery B. Normally all the relays are unoperated and the battery is not connected to the generator. When the load current rises to 2À5 amps., relay 1 operates due to both windings acting in conjunction and energizes relay 8 which connects the generator over resistance 39 to the battery, the value of this resistance being such that a charging current of 3À5 amps. is supplied. Relay 1 also inserts a resistance 154 in its own circuit and energizes upper (opposing) windings of relays 3 .. 7. When the load current rises to 5 amps., relay 2 operates over its lower winding alone, connecting its upper winding in partial opposition and energizing relay 9 which connects resistance 40 in parallel with resistance 39 thus increasing the charging current to 7 amps. When the load current rises to 9 amps., relay 3 operates increasing the current in the upper windings of relays 4 .. 7 to prevent them also operating at this time, and energizing relay 10 which inserts a third shunt resistance 41. Relays 4 .. 7 act similarly in response to further increases in the load current. When the load falls the relays release in succession but in reverse order to give corresponding control. Switches 46 . . 52 provide manual control of the charging current. In an alternative arrangement, the relays 1 .. 7 are all energized under no load and release successively in response to increases in load, only one however remaining de-energized at one time so that the resistances 39 .. 45 which are of different values are connected singly and not in parallel combinations. |
