Patent GB-1261849-A (GB)
Title: A telephone charging device
Inventor: BELLEC CHRISTIAN LE
IPC: H04M15/00
Filed: 1970-09-01
Abstract: 1,261,849. Telephone metering systems. C. LE BELLEC. 1 Sept., 1970 [29 Aug., 1969], No. 41829/70. Heading H4K. Metering is effected by a common storage arrangement in response to a data word containing call particulars including the caller's address, the charge rate and a discriminant to indicate if charging is to be a fixed initial fee or to be computed according to duration, the particulars being stored at register 10, Fig. 1, on receipt and, if the discriminant indicates a fixed charge, being transferred to a central accounts centre; the particulars being put into a free one of a plurality of stores arranged in groups 1 to 4 if the discriminant indicates charge by duration, each group of stores having its own processor 205, Fig. 2, which selects a pulse train according to the charge rate in the particulars and accumulates a metering total by circulating the particulars from store to processor and back to store and augmenting the total each time a pulse of the train appears; the charge particulars and the accumulated total being transferred from the storage group to the accounts centre when the register 10 receives an end-of-call code. The common control of the exchange is referred to as a multiregister and delivers the charging particulars and end-of-call codes to the register 10 of the metering circuit shown in Fig. 1. The circuit is sequenced by a so-called programmer 0 which steps off state # 0  to # 1  to gate the received particulars to the register, steps on to # 2  and beyond to allow the register 10 to circulate its contents over the gates 18 and 15, and steps to # 3  to examine the charge particulars in decoder 17. If the particulars indicate a fixed charge the sequence advances to # 4  which puts the particulars in 10 through a gate 20 for immediate transmission to the accounts centre. If a subscriber's meter has to be operated to register the fixed charge or if a pay station has to be signalled to call for a prepayment, the particulars contain such instruction and the phase # 5  is demanded so that the particulars are transferred to an auxiliary store 9 from which they gain selective access to the required line by way of output register 13. If duration charging is required the sequence advances to # 6  in order to find a free store in one of the groups 1 to 4. The constitution of one such group is shown in Fig. 2 as comprising four stores 201 to 204 each capable of holding five charging words. The group processor 205 cycles over the stores in turn taking one word from each store and progressing from word to word in each store at each pass as controlled by a so-called word interlacing circuit 218. At step # 6  the words in the stores are read out in sequence to a comparator 206 and the first to show zero contents opens gate 208 to signal a free storage area. The programmer 0 has a priority chain to choose one from concurrent free stores signalled from more than one storage group and responds by demanding sequence state # 7  and that mode of the sequence state # 71 , # 72 , # 73 , or # 74  which gains access to the selected storage group 1 to 4 and effects transfer of the call particulars from register 10 over gate 217 to the free storage area in that group. The stored particulars are now circulated through the group processor 205 which from the charge rate data selects a pulse train from a repertory available from clock 12 so that the call charge can be accumulated at an appropriate rate by addition whenever circulation of particulars through the processor coincides with a pulse of the selected pulse train. At release of the connection being charged an end-of-call code is received in register 10 which code contains call particulars and advances the programmer to sequence state # 8  at which the comparator 206, Fig. 2, matches the particulars against those in the stores 201 to 204. A match opens gate 209 to advance the programmer to state # 9  and that part of it # 91 , # 92 , # 93  or # 94  which corresponds to the store producing the match and effects transfer of the accumulated charge and particulars in that store to the register 10. The sequence is now reverted to state # 4  to send the data to the accounts centre over gate 20, Fig. 1. If, during a call charged by duration, it is necessary to operate a subscribers meter or send pay tone to a paystation, this being indicated in the call particulars, the processor 205 loads an associated auxiliary store such as 6 so that on each occurence of a pulse of the pulse train selected according to the rate of charge the store 6 obtains access to the exchange by way of output register 13 to gain connection to the particular line; paytones being applied 15 seconds before payment is due. The pulse trains giving rate of charge are switched according to the time of day to alter the tariff.