| 摘要 |
1354739 Coin box telephones INTERNATIONAL STANDARD ELECTRIC CORP 20 Aug 1971 [21 Aug 1970] 39153/71 Heading H4K [Also in Division G4] In a toll-charging arrangement for a coin-box telephone the values of the coins inserted are registered via coding units 4 and adder 5 in a store 6 and the courting pulses from the exchange are registered via a coding unit 11 and adder 12 in a second store 13 having outputs 17 to 19 for controlling coin collection (highest value coin collected first) and connected to a complement stage 20 to effect reduction of the contents of stores 6, 11 by the value of the coin collected. In the embodiment shown the stores 6, 11 are connected to a subtractor 10 the outputs 21 and 23 of which control credit indication and forced interruption of the call, and the output 22 indicating before the start of a call whether the minimum fee has been inserted. In a second embodiment (Fig. 2, not shown) the subtractor is dispensed with and the counting pulses are applied via complement stage (42) and adder (28) to the first store (29) outputs (31) to (33) of which are associated with minimum fee, credit indication and forced nterruption. |
