ES280338A1 - Coin collector for telecommunication services - Google Patents

Abstract

A coin collector of the post-payment type has a differential credit/debit mechanism and an oscillator which generates pay-tone when payment for an established connection is required. The pay-tone obliterates conversation until sufficient coins have been inserted to establish credit. When credit has been exhausted paytone is reconnected and further coins must be inserted to renew credit if conversation is to continue. The collector has coin slots for three coins, threepenny bit, sixpence and a shilling, and the slots are normally closed by a solenoidoperated plate. The coin collector substation circuit is shown in Fig. 3 where contacts SW1, SW2, operate when the handset is taken down. Having dialled for a connection and obtained reply, reversal of battery from the exchange operates coin slot plate solenoid SUR to enable the user to insert coins into the collector mechanism (see Division G4). Metering pulses of 12 kc/s. are detected at TC and connect a magnet 32 of the debit side of the differential debit/credit mechanism to a local battery B. Contacts X controlled by the differential cage of the debit/credit mechanism isolate the oscillator OSC until the first meter pulse is received from the exchange to move the cage into debit. The interval between reply and the first meter pulse gives time for identification before the contacts X close and pay-tone is generated. A drum indicator set by the debit/credit mechanism shows the user how much thas been debited initially and this amount plus more to establish credit must be inserted into the collector before contacts 61 change-over and disconnect pay-tone. As the conversation proceeds further metering pulses are returned at a rate, or in variable number at fixed intervals, according to the connection obtained and when credit has been exhausted contacts 61 reconnect pay-tone to demand further credit. When the credit mechanism moves to its maximum position contacts 60 change-over to release solenoid SUR and close the coin slots. Contacts 60 also change-over when the debit mechanism reaches a maximum position and since contacts 61 are as shown with debit the connection is released. Maximum debit is most likely to arise with failure to hang up the handset. When the handset is hung up the credit/debit mechanism is reset to normal by a mechanical linkage but where credit is in hand at the end of a call it may be employed for a further call by releasing the connection with a push-button which breaks contacts W while the handset is still offhook. Where charge is made in multiples of fourpence it can happen that the full value of inserted coins is not transferred immediately to the credit mechanism (see Division G4). On insertion of sixpence the mechanism credits fourpence and a value of twopence is held in suspense. A further threepence inserted registers as fourpence leaving only a penny in suspense which is collected with another insertion of threepence to square the account. Such suspended values may be left in the mechanism after release despite replacement of the handset or their use as credit may be restricted to consecutive calls where release is made by contacts W. An indicator drum shows the amount of suspended credit available. A rectifier RF enables the local battery B to be charged from the exchange when the line is idle.