BE548682A - - Google Patents

Description

       

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   The present invention relates to telephone systems in general and relates more particularly to improvements made to the provision of a shared line for a telephone system in which telephone sets connected to the shared or common line are provided with equipment. prepayment and ensure the secrecy of communications,
The invention disclosed herein constitutes a direct improvement of the invention disclosed in the United States patent application. Serial 506,453 filed May 6, 1955 by Clarence E. Lomax.

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     In general, the. present invention aimed at ensuring the secrecy of communications to users of prepaid stations when several hens a. preparement are connected to a common line with two conductors, as in the previous patent application. However, the particular object of the invention is to ensure that the access denial system is controlled independently of other required signals.



   One characteristic of the present invention lies in the fact that the access prohibition system and the prepayment station are controlled by a pulse of a predetermined frequency.



     Another feature of the present invention resides in the duplication of the tone detection circuit, at different frequencies, to perform the function of access prohibition and that of release. These and other features of the present invention will become apparent in the course of the description which follows.



   The system according to the present invention has been established with a view to providing a fully automatic service to a user who initiates a call originating from one of said prepaid or grouped line stations, to any local subscriber. , as well as to ensure at the same time and with the help of an operator, an interurban service and a communication service between 'two stations connected to the same shared line.

   The electronic coin of each prepayment station is controlled automatically from the central equipment, so as to perform either a collection operation or a refund operation, when it is a local call. , as well as a collection operation in the case of an established long-distance call, this appliance being however controlled manually from an operator position in the case of a call between two stations

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 of the same shared line or in that of an interurban call not established.

   It should be noted that the circuits shown here include Strowger's stepping switchgear, well known per se, which has been indicated by a schematic diagram in the drawings, although the invention is of no significance. limited to the use of such switches,
On the basis of the foregoing, the present invention aims to establish a telephone system comprising group line prepaid stations, this system comprising an access prohibition relay in each station, in order to prevent access to the line. to non-calling or non-called stations, this relay being controlled by the equipment provided both at the central office and at each prepaid station, the invention also relating to the equipment operating so as to provide the following services. above in an economical and improved manner.



   Fig. 1 shows the details of a group line prepaid station circuit and also shows a second prepaid station, designated by the reference sign P2, connected to the same line. La'fig. 6 shows the details of an alternate bundled line prepayment station circuit which uses a transistor instead of a gas discharge tube as used in FIG. 1, this circuit being able to be used instead of the prepaid station circuit of fig.1.



  It is considered that four sets in total are connected to line 100, although not all have been shown and, on the other hand, grouping is not necessarily limited to four.



   Freezes them. 2, 3 and 4, taken together, represent a repeater circuit 200, individually assigned to the

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 line 100 and, consequently, common only to the four stations connected to this line, FIG. 5 shows part of the operator's equipment, thanks to which the latter can connect to the repeater and control the operations of prepayment and sending of call signals.

   A number of such repeaters can be provided at the exchange, ie, one for each group of shared line prepaid extensions connected to a single line; however, for purposes of the present invention, it will be assumed that repeater 200 is the only one used. The repeater circuit terminates at a number of operator positions, only one of which is referred to herein as jacks J1. J2 and J3 in fig. 5.

   The operator has access to the jack Jl through a cord circuit of a well-known type, which enables her to converse with a calling subscriber from a group line or to establish and control a conversation communication to another user, from or to a group line subscriber; on the other hand, it has access to the J2 jack via the casing cord 520 and, to the J3 jack, via the call cord 510. The use of a circuit -de repeater assigned individually to each grouped line is dictated only for economic reasons since it is not necessary to provide a large number of prepaid stations in any exchange.

   The control equipment included in the repeater circuit can easily be included in seeker-selector links, when there is a large number of grouped lines; however this would require the installation of such equipment in all the links having access to the grouped lines, in fig. 7 shows the circuits of the tone generators intended to send tones

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 blocking and unblocking repeaters. We have shown the common tone generators capable of powering a number of repeaters. However, you can use tone generators assigned individually to each repeater.



   A calling user initiates a call from one of the prepayment stations P1 in the usual manner, by picking up the handset and depositing coins of the appropriate value. The present invention has been known, by way of example, for use with a prepaid mechanism;

  nent intended for two American 5 cents coins or pouf one American 10 cent coin, retort described in U.S. Patent No. 2,674,655 issued to Gallagher on April 6, 1954, mechanism in which a requesting user must deposit either a 10 cents coin , or two pennies, before the cam contacts can function effectively. An electro trigger 40, actuated in conjunction with the electro-collector 50, causes the springs 5 to be covered with five cents, in the event that these springs have not been brought to rest previously, while the electro coin 50 returns the other elements of 1 device to their initial position at the end of a call.

   The repeater circuit 200 common to the four users is attacked when the handset is picked up. Following this attack, the repeater sends a momentary AC access prohibition pulse of 7,000 periods on the two conductors of the line, to each prepayment station of the latter.



  In these prepaid stations, this current - which flows through a series resonant circuit made up of capacitors 17 and 18, a coil 70 and a resistor 10 - determines the appearance of a voltage of the order of 100 volts between the cathode and the starting electrode of tube 15. The tube at

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 cold cathode 15 fires and causes relays 130 of all stations to attract. This determines the attraction of the relays 120 of all stations except the calling station, where the control circuit is open at contacts 4 of the switch hook. Each relay 120, when it is drawn into a non-calling station, locks up on the pads 124, disconnects the station to which it is assigned from the line and, through the pads 122, modifies the resonant frequency of the tuned circuit.

   The tube 15 defuses at the end of the access prohibition pulse, which allows the relay.



  130 to fall before the relay 110 has had time to attract. The lamp 95 lights up in parallel with the access prohibition relay 120, thus indicating, to those who would like to use this station, that it is temporarily disabled. After the call barring or disarming pulse fades, a transmit tone is sent over the line, indicating that the appropriate amount must be deposited, otherwise the transmission cannot be made. carry out.



   The prepayment station in FIG. 6-operates in a manner analogous to that of the prepayment station of fig.l and can be used instead of it, together with. the repeater circuit of figs. 2, 3, 4, 5 and 7.



   A user initiates a. call by lifting the handset and entering the appropriate amount. After being attacked, the repeater sends a momentary direct current access prohibition pulse of 7, or periods, on the two conductors of the line to each of the prepaid stations connected to this line. At the prepayment station in fig. 6, this alternating current passes through a series resonance circuit for a half-period composed of capacitors 17 'and 18' and a coil 70, as well as the resistor.

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 tance 10 'and the rectifier 19 and, during the other half-period, a transistor 16'.

   The current flowing through this transistor goes from the emitter to the base, determining an amplification of the power rlu current in the local circuit of the collecting electrode. This results in a positive potential supplied to the emitter of the transistor
15 'and passing through the latter to end at the collector, from where this potential goes through the relay 130', to end at the negative pole. The potentials required for such an operation of the local circuit are supplied by the local rectifier system constituted by a bridge of rectifiers 81 'with dry discs and by a transformer 80', a system whose operation is obvious.

   The operation of the elements of this circuit, as it takes place after the attraction of the relay 130 ', is identical to that of the corresponding elements of FIG. 1.



   In accordance with current practice, a + 110 volt battery is used to control the coin operated 50, so that it collects an amount, and a -110 volt battery to bring this electro to repay an amount. In the following discussion, it will be assumed that the P1 prepayment station has been connected to the line, although the operation would be the same if the prepayment station of FIG. 6.



   In the case considered here, the repeater circuit SOC is individually assigned the sector Stroager 490.



  The first digit formed by a user of a group line extension, who wishes to call another user of the same line (intercom call) or form a long distance call is "zero". This has the effect of raising the selector carriage to the tenth level, where the idle shaft contacts (not shown) of this selector switch.

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   would do so as to return a land to. repeater, so that the latter triggers the triggering of selector 490 and sends a signal to the operator by lighting a lamp such as 471.

   The selector can be provided with means of any other well-known type intended to return a ground in the event that the formation of an intercom call has started with the transmission of a predetermined digit. , other than zero. In the case of a local call, the selector 490 raises its ciiariot to a desired level, other than the tenth, to seek then-. and driving a free switching apparatus 495 (including a connector driven either after the formation of a second digit or after the formation of the loan digit) in a manner well known per se.

   The number of digits formed obviously depends on the size and arrangement of the system to which the present invention is applied. The repeater is set up in such a way as to prevent an entry on the line by an attendant in a call that has not been routed to the attendant set. In this case, the switching apparatus is operated by the other digits, so as to establish the connection to a called subscriber, for example subscriber 57.

   When the called party answers, the connector reverses the polarity of the positive and negative conductors, fig. 4, which has the effect of attracting the relay 430, the arrangement being such that, at the end of the communication, the repeater automatically collects the -, and applies an unlocking potential of 500 periods to stations which were out of service until then.

   When any call is interrupted by the calling party before it is answered by the opera-. caller or correspondent requesting, the repeater automatically ensures that the electro-currency of the requesting station reimburses the amount and applies an unlocking current so as to release the access prohibition relays in

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 all stations and to connect the Junction + L and-L conductors of line 100 to all doors.



   A busy light, such as the 470 light, turns on at all operator stations whenever a repeater is attacked. After receiving a signal, for example using a 471 lamp, whether it is a long distance call or an intercom call, one of the operators pushes her card into unjack such as J1 and establishes a chat connection to the calling party. After having obtained the required information, it establishes communication, in the case of a; long distance call through its cord circuit (not shown).

   Before routing the call, or at any other time when it has access to the repeater 200, the operator can, by manual intervention, cause the collection or reimbursement of the coins.



   After the establishment of the long-distance call, the repeater which was brought to the collection position by the attraction of relay 430 following the operator's response collects the coins which had been introduced
In the case of an intercom call, the attendant recommends that the calling user hang up while she is sending a call signal to the start party. Intercom calls, while probably of little importance to passing people, must be provided for users who live or work in the region and who must be able to communicate with. other users, connected to the line, two users, namely the calling party and the called party, periodically receive a call signal.

   A selective call frequency, individually assigned to the requested set, is applied from a key such as K4, K5, K6 or K7, to activate the desired ringtone, so as to

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 send a call signal to the called station. The attendant cannot send a call signal to the called set because she has not reconnected it to the line, which she can do by inserting call horn 210 in the jack J3 and by activating the key 28 alfected to the call cord.

   having connected the called party to the line again, the attendant periodically activates one of the keys mentioned above, namely the one assigned individually to the frequency of the called user, which is indicated by the last digit of the call number of the called party, so as to send a call signal to the latter party. The calling party's call bell is activated by intermittently operating a key assigned to the cord 510, which is itself assigned individually to the frequency in question. The calling user knows that he must go back to the line when his call bell stops being activated periodically. When the call is answered, the attendant is informed by a signal.

   It stops sending call waiting, and the calling subscriber goes online.



  The repeater 200 automatically performs the prepayment tests when the communication is interrupted, and, the prepayment being noted, the collection battery is connected to the line. When either the calling user or the called user goes on line, the attendant is informed by a signal consisting of the illumination of a cord circuit lamp (not shown, actuated from the repeater. the first user to go on the line sends the attendant a signal through the operator's cord lamp.

   The operator performs all operations through the common repeater for the grouped line,
Note that the calling user, in the case of a long distance call, or either of the two

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 EMI11.1
 users, either; la ::: r: àïlci4 4ae or defend him, when he is aware of a call ù'intercOMr! on (in the case where the other user has picked up) can: 1: ',:

   : 0 twinkle the 1z # i.pe- of cordol or call of the operator, by shaking several times its hook COiil,: UtéLt21.tl ', of D'e:; one to open and a f-81' fr d, -;> iden.ant loop ai. âx 'repeatedly, without running the risk of being disconnected following the closing of contacts such as 4, give that the prohibition pulse sent to the various <iCess prohibition relays was not operational: ;:; '1t: a that. yC, 'Ly-: ilt 411 g C'r. ^ -. --- ci Y'.x during the initial repeater attack, .n. ce:;! at2 '.? i.f.' and B.vm "t de rendrs k ..? COl ':( SY011étÓ.nt 1: 1'3 {iaJide Llr the service required by c.9i-'C; gl' 'J,}' 8 X ':: r ;; rj, this will want to perform Li11.2,5'rp in order to Cs3I û:, '' s, tr: Cv if one, piGC- ';:' (1e Gonnsie 2. been deposited, 311th c'.GCOlïi p], 1 "1 this test by inserting U11 test lead summer. :: 1Céiiss3.; slow o20 d to <25:

  .1n ja2k e. ', And erf activating a .l3 key, which will have for Effect é,' éclai = <- =, the l ::. ULpe 540 08.ns the case where a part has been introduced. b .5 .: 'Lß.iV d'G1 V1. l4v.t can sneuite act accordingly and; w'3..L ..iu7S:.,;, û 'any douie concern the n..oXltü1.t, it can operate the reimbursement by pressing 1s. key 1iy of :::: .. ::; one to apply the potential of the e!: bou1'se, ment to the electro with appropriate griddle if elect wishes to determine 1 '± ncaisenient of a part, it activates the. key K2, from fsgon to be applied to the cash-out potential 8. the coin-operated electronic system <
 EMI11.2
 When it is a long distance call with hold,
 EMI11.3
 1- '1;

  éré-ti'icé can reimburse the amount using the o20 cord circuit, after having recowm811dé to the cor'xwst 4zdant defender of x accxocYrx '... then frees it all the stations by activating the key ïi85 the' 510 cord being inserted in the J3 jack, so that das calls can be weakened sheepishly that it tries to reach the correspondent request. It "E'ùenà that the repeater 2UV is free and

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   calls back the calling party, while putting the called party on hold.

   Before establishing the conversation connevion through her cord circuit, in any way, Empress invites the requesting correspondent to: introduce the appropriate denier into the slot. The repeater automatically collects the amount when the communication is released.

   As long as the repeater 200 is free, the operator has access to any of the two users of the line by simply inserting her call cord 510 into the J3 jack, in action. by inserting the appropriate call key and inserting the plug of its cord circuit into jack J1, so as to establish a conversation circuit to the calling party when the latter is on the line.



   Paid calls payable by the called party must be set up through an operator having direct access to the repeater 200. The operator establishes the call via his backbone circuit coming from the operator. long distance by first sending a signal to the desired extension, as described above and inviting
User thereof to deposit the appropriate coin which is automatically cashed by the repeater after release of the call.



   Incoming calls from a local subscriber, such as subscriber 58, or from a long distance operator, that is to say, calls for which the called party must not introduce a room, are established. through a switching device such as 390 and a connector such as 395.



  Connectors such as 395, which have access to the repeaters of prepaid stations, are set up so that a selective call, individually assigned to the requested station, can be sent to it through the repeater, following transmission of the last digit to the connector.

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   This arrangement is used very generally in connectors having access to grouped lines. In order to. to demonstrate the mode of operation of the present invention, the connector is described here as a three-digit connector, although other arrangements may be adopted, for example where each connector having access to the group line is established so as to provide a frequency individually assigned to this connector and, on the other hand, individually assigned to a set of the group line. Of course, the connector is attacked after a suitable number of digits have been transmitted through the selectors forming part of the switchgear 390.

   In the case of a call to a shared line, and assuming a three-digit connector is used, the first two digits control that connector to connect to the line. group desired, while the third digit controls this connector so that it selects a frequency assigned individually to the called station connected to the grouped line and that it applies the frequency thus selected to the line, in order to send a signal of call to the requested user.

     The repeater is blocked on the connector benches vis-à-vis all other incoming calls, as well as vis-à-vis the operator, and when the called party answers, this connector automatically deactivates the sets. non-callers.



   Silly local calls.



   Removing the handset of set P1 (which we assume to be the calling set of the grouped line) from its hook switch has the effect of closing contacts 1 and 2 and covering contacts 3 and 4, as shown above. , Opening the contacts 3 ensures that the

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   @@@@@ call rie 90 ceases to be branched on the line, while the opening of contacts 4 results in relay 120 remaining in its triggered position when the inhibit pulse access is sent to the rest of the line.

   The circuit is established towards the repeater 200, so that it causes the attraction of the access prohibition relay of all the other stations of the grouped line, which relay is thus brought into its blocked position; however, establishment of the appeal is not possible until an appropriate amount has been deposited.



   The closing of the contact springs 1 at the station P1 has the effect of establishing a circuit starting from the negative pole of the battery and passing through the coil of relay 360 of FIG. 3, the upper primary coil of the translator 402, the pads 351, 331, 221 and 211, the line conductor -L, the pads. 121., the coin drop microphone 12 and the resistor 13 shunted on this, the telephone microphone. nique 20, the induction coil 9, the springs 1 of the switch hook, the impulse contact 8 of the dial, shunted by means of the springs 6 and the coil 40, then towards the springs 123 and the line conductor + L, through the latter conductor, with return via the pads 213 and 223, the pads 334 and 353, to the lower primary coil of the translator 402 and then to earth.



   Relay 360 draws into this circuit, by closing pads 362, and establishes an obvious circuit for delayed pull relay 410 of FIG. 4. The relay 410 causes the closing of the pads 411, 412, 413 and 414. By the pads 413, an obvious circuit is established for the relay 370 which draws on the earth conductor C 'by the pads 378, blocking thus the repeater 200 vis-à-vis incoming calls pax through a connector, such as

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 the connector 395. By the pads 414, the relay 410 establishes a circuit, from -114 to 326, intended for the relay 330.



   Relay 350 applies an alternating current of 7,000 periods from terminal F1, through the terminals
357 and 271, at the primary of transformer 304, after having grounded the ST oscillator start conductor, after which the 7,000 period tone is applied, through pads 332 and 335, to the two line wires .



   Relay 360 does not drop during the transmission of this pulse, given a shunt circuit formed by resistor 301 and pads 375, which is established by preliminary working pads 333 of relay 330. Simultaneously, relay 330 closes an obvious circuit for relay 320, via pads 336; however, the relay
320 is delayed pull and therefore allows relay 330 enough time to fully saturate before the circuit of relay 320 opens at the pads
326 and that the access prohibition frequency pulse is removed from the line wires.

   The access inhibit frequency can be provided by any type of AC generator, an electronically coupled transistor oscillator being shown by way of example only.



   All the prepayment stations connected to this line are connected to this generator, and their relays, which correspond to the relay 120, occupy a position such that the pads 121 and 123 are closed, as well as the hook-switch contacts which correspond. to contacts 4, except to. calling set, or contacts 4 are open.



  When the access prohibition pulse of 7,000 periods is applied to the line wires, the gas-filled tubes which correspond to tube 15 are ignited, given the potential present at the terminals of impedance 70 and

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 of the resistor 10 of the series resonant circuit, which comprises the capacitors 17 and 18.



   The signal level of the 7,000 period access prohibition tone may be of the order of five volts at the exchange; however, given the losses during transmission, this level is reduced to a few volts only at the coin-operated station. Due to the high overvoltage coefficient of the tuned circuit, a voltage of the order of 100 volts baited across coil 70 and resistor 10. The sensitivity of the tone detection circuit was intentionally expected to be quite low, in particular. adjusting the taps on coil 70 so that the strongest speech signals are below the threshold required to prime tube 15.



   When tubes corresponding to fil'15 are primed, they establish a circuit for the relays corresponding to relay 130, in each prepayment station.



   As a result, it is established at the pads, which correspond to the pads 131, a circuit passing through contacts which correspond to the contacts 4 of the switch hook and to the pads! relay 111 and 125, circuit intended to attract a relay corresponding to relay 120, in all stations except the calling station, where the circuit is open to contacts 4 of the switch hook. Each attracted relay which corresponds to the relay 120 blocks itself by pads which correspond to the pads 124 and, by pads which correspond to the pads 122, modifies the resonant frequency of the tuned circuit while, by the pads which correspond to the pads 121 and 123, it disconnects the related extensions from the line.

   When the resonant frequency of the tuned circuit is changed, the cold cathode tubes become de-energized, and the relays corresponding to relay 130 drop. Access prohibition relays activated

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 said in the position of prohibition, going to the posts. prepayment temporarily put out of service, a lamp corresponding to the lamp 95 remains on in a circuit parallel to that of the access prohibition relay, so as to indicate to any users that this prepaid station is temporarily put out of service.



   During the interval when the access prohibition pulse was on the line, the repeater attacked the selector assigned to it. The relay 370, by attracting, closes the pads 373, sending an earth potential through the previously closed pads 411, as well as the rest pads 443; so as to actuate relay 450.

   This last relay closes a circuit from the negative wire of the selector
490 and passing through the work pads 452, the upper secondary coil of the translator 402, a coil of the polarized relay 430, the lower secondary coil of the translator
402, the pads 361, the working pads 454, to end at the positive wire of this selector, After being driven, the selector 490 sends back a transmission tone to the repeater;

   however, this tone is prevented, by the pads 321 which bypass the translator 402, from reaching the prepaid station during Interval where the access prohibition pulse is manifested. @
After the access prohibition pulse has been removed from the line, relay 320 clears the shunt of the trans. lator 402 by the pads 321 and establishes, through the pads 323, an obvious circuit for the relay 310, so that the latter marks, by the pads 311, the occupation of this line of prepaid station vis-à-vis. screw of the operator, by switching on the occupancy lamp 470.



   The user of the prepaid set receives a transmission tone, which constitutes for him the indication that he must insert a coin into the slot and start in-

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 following the transmission of the desired number. In accordance with current normal practice, the shunt contacts 5 close following the introduction of a dime, while the coin springs 6 open and the springs 7 close. also close. The deposit of a second penny only causes the opening of the shunt springs 5. The insertion of a dime does not affect the springs 5; however it causes the closing of the springs 7 and the opening of the springs 6.

   The deposit of a first five-cent coin has the effect of establishing a circuit starting from the earth located to the right of the relay 60, this circuit passing through the electro coin 50, the contacts 7, the electro trigger 40, contacts
5 and 8 shunted, contacts 1 of coil 9, vocal microphone '20, coin drop microphone 12 and resistor 13 shunted, pads 121 and the negative line wire to the repeater and then by the path described above, to relay 360 and to the negative pole of the battery. The deposit of a dime has the effect of establishing the same circuit, except that the contacts remain open.

   It will be noted that the earth which is present on the line wire + L shunts at this moment the triggering electro 40, the coin electro 50 and the relay 60. The contact springs 5 are only operative when only one coin is deposited, in which case they act in such a way as to prevent the transmission of numbering pulses capable of controlling the line relay (not shown) of the selector, this in a manner which will be described below. -after.



  The deposit of a second dime simply has the effect of opening the contact springs 5, so as to allow effective operation of the cardran, while the deposit of a dime, instead of 2 coins of five cents, has the effect of closing the circuit described cī

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 above, except that the shunt contacts 5 do not close at any time.



   The requesting correspondent (assuming that the coin of appropriate value has been deposited) operates his call dial, so as to open and close the cam contacts 8 a number of times corresponding to the number formed. This has the effect of opening and closing a corresponding number of times the loop towards the relay 360, so that this relay is energized and released a corresponding number of times. When falling, the relay 360 closes the pads 363, 376 and 435, of a circuit going to the relay 420, which is thus excited, and by the pads 421 closes a circuit to promote the excitation of the relay 360 after each release, so that the latter is fully and quickly energized after each closing of the cam contacts 8.

   This special excitation circuit has been provided for the reason that relay 360 is interposed in a high resistance line and, therefore, is likely to have an excessively fast drop-out period. The selector line relay receives pulses via the pads 361, so that this selector is actuated, in a well-known manner, so that its carriage comes to occupy a position corresponding to the figure formed. The 405 silicon carbide resistor, branched off to the impulse contacts 361, slightly delays the drop-out of the selector line relay when the latter contacts open after the selector line relay has provided an inductive shock. momentarily lowers the resistance value. This resistor also serves to protect the impulse springs 361.

   The use of this resistor is preferable to that of a capacitor, which is liable to discharge and accelerate the dropout of the selector line relay. This can be a problem with a slow dial, as the 360 relay provides

 <Desc / Clms Page number 20>

 
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 long ià; pL1l; .ie> <i open. '', saw ..; uu dnL-'c.'U.l'i '' ¯ .... Li,; lOn ":: L18 f! l:) U1L'l ()! 1 OUV" .1.'l. ", Vil, A,) 11 J.dl .., .. l,. (. '. <. ..1- "'d.' \ -Cl., 1: .11C'- u lüE.lG '. Ri :: 1, L; mc>.



  > n bUP) '¯) [Uat il'Iiixie of a Uj.J1J.Ù lÜC: i.l1, 1 selector carriage. 1..: ...; 1 ..... 18V '; -j. a level! ßlA: nOitU. ' except the dixi:, ..: y ± .1. la sui:,:, du) l'3 ni'3! ' ci.Lzrey '1) 1' (;;.: ..ia <; 1 it seeks and! ttirltd'Un3;!: ..; l1i ':: the 8 well coined 3 ..: "1,: ') Í wa selector or a book cOtmecbeur, y ca: .t. That of (.: 3i .-: nÉ: by the rectangle ü..l'qaê "a9 ;;,': nl of CGL.UG:fn ¯wit and establishes an excitation loop, which includes secondary coil 402, pads 361, and positive and negative wires, to the line relay (not shown) of the next switch.

   A series of digits then formed by the requesting party actuate the relay 360 a corresponding number of times so that the latter opens and closes the pads 361 in a corresponding manner and actuates the apparatus.
 EMI20.2
 following computation reillage 495, which c oaprend a connector, so as to position this apparatus in accordance with the series of numbers formed. This latter device then connects to the local subscriber such that S7 applies inrush current to the requested line and sends back a ringing tone on the excitation loop of the connector, the translator 402 and the loop to the calling party, if subscriber line 57 is free.

   The calling party now knows that the called party is receiving a call signal. bi the line of subscriber 57 is busy, a busy tone is returned to the aforementioned loop, so as to indicate that the subscriber's line
 EMI20.3
 requested is busy. The called party, by answering the call, causes the connector to reverse the polarity of the battery on the positive and negative wires, with a
 EMI20.4
 business well known in itself.

   When the polarity of the conductors is Inve "1, 1 ;, the rectifier 404 no longer shunts the upper coil of the relay 430, and operates in series with

 <Desc / Clms Page number 21>

 the excitation loop of the line relay of the connector, so as to open the pads 431 and 435 and to close the pads 432, 433, 434 and 436. The pads-433 at this time shunt the upper coil of the relay 430; however, the lower coil of the latter is energized in the circuit comprising the pads'436, the conductor 437 and the. pads 314, so as to maintain the pads of relay 430 in the actuated state.

   The pads 435 open a point in the circuit to the relay 420, while at the pads 432 a circuit is prepared intended to supply the potential of cash - - sow to the electro coin 50 present at the prepaid station -. ment applicant.



   If the called party does not answer for some reason, or if the calling party has not operated the following selector or switches, the battery current polarity is not reversed on the positive and negative wires, and the relay 430 does not attract.



  By putting down his handset, the calling party opens the springs 1 of the switch hook, thus interrupting the loop to relay 360. The latter drops out, causing the selector line relay to drop out via the pads 361, after which the latter is released. The circuit of relay 410 opens at pads 362, and this relay drops out after a certain time interval, causing in turn, through pads 413, the dropout of relay 370.



  The relay 420 draws into its excitation circuit described above, this after the drop-out of the relay 360, but before the drop-out of the relay 370; however, and as' it was explained above the excitation of the relay 420 does not have the effect of activating the relay 360. In addition, the relay 410 causes by the pads 414, the opening of one of the circuits. for the relay 320 and, by the pads 411, opens the circuit of the relay 450, which has the effect of disconnecting the secondary of the translator 402 from the

 <Desc / Clms Page number 22>

 positive and negative wires going to the selector.

   On falling, the relay 370 cuts, by the pads 377, another bonding circuit for the relay 320, and the latter drops out by closing the pads 324, thus preparing a circuit to apply a pulse to release or restore access from alternating current at 6,000 periods at the + L and -L conductors and, by means of the pads 323, opens the circuit of the relay 310, which, being with delayed release, cannot yet drop out at this time. By opening, the pads 378 eliminate the earth of the conductor C '; however, the pads 379 would, so as to keep this conductor C 'to the ground, thus blocking the repeater with respect to the pads 316.



   Furthermore, the relay 370, on falling, closes the pads 372, before the relay 320 drops out, so that a circuit is established, through the pads 355 and 322, for the attraction of the relay. 230. An earth is applied through the pads 232, in order to glue the relay 310 and thus maintain the occupation of the repeater from the earth, through the pads 315 and 379, when the relay 370 is triggered. The relay 230 establishes an obvious circuit for the relay 220, through the pads 231 and, in addition, opens the pads 233 to prevent the relay 270 from attracting until the coin handling is complete.

   The relay 220 attracts and, at 225, keeps the lamp 470 lit by the intermediary of the conductor B, and closes the pads 226. The relay 250 is now interposed in a circuit starting from the battery and passing through the coil of this relay, the closed studs 371, 241 and 261, the work studs 222 and 22i, the line conductors -L and + L going to the prepayment station, the tripping electro 40, the contact springs 7, the coin electro 50 and relay 60, to lead to the

 <Desc / Clms Page number 23>

 
 EMI23.1
 earth, that if 11 "" 1) "" 'CL "(1 <> f4 on (;, i O a t4tw'.: ':; /); 6 :. Z ... t..¯L .. .- 350 a't.ti.re àe i # .éini ±; j¯> <;> i; r; jr ;; <; r plots 1, -t'in ± '"; .ta":' .ir 350 at.t 1re a8 LÜ 11J.,): IX '(, 1. les [l 0,' J., "L J..J- - c, c. ,, ¯.¯ Him .'a .nÇ.'Y "7t: 11; 2Gg,., '1 ..

   CI LU1 other Ci1li4l.Jt d ': 3.tt.rac tJ011:) our 1: r'.L .... 2.- ... wJ,, V l "-' = -.... plots bzz, the relay 260 prepares a circuit leaving Q9 ï 'ē impulse transmitter P6 which is common to all the repeaters: such as the repeater JOO, at which iinatzonr e da fàion parmanente.



  When the plots: Fl assigned to the can-s in: CÉ; ri3lJ.re â6 1 'net ,: of pulses P6, are faxcr: s, a ground is sent by the input of plots 252 and 24b} to produce the atti, action of relay 240. This last relay attracts, and closes the pads 243, so as to establish another bonding circuit for the relay? C59 in addition, it fex'I; 18 the bzz pads so in establishing its own colla6e circuit starting from the earth present on the pads P2, which are kept closed by the upper cam of the pulse emitter 6 for a predetermined time. Furthermore, the relay 240 opens, through the pads 246, its own attraction circuit and, through the pads 41, cuts off the attraction circuit, described previously, for the relay 250, which drops out.



   By attracting, the relay 240 closes the pads 242, so that the repayment potential of -110 volts is applied, through the pads 431, to the conductor 291,
 EMI23.2
 pads 24 261, 222 and 224, respectively, 211 and 213 respectively, to the two conductors -L and + L..t ;; ta ... 'rlt gives that the contacts 1 of the switch hook are open, the potential of -110 volts is applied only to the side of the circuit of the prepayment station which is connected to the line wire -L, to the release solenoid 40, to the coin contacts 7, to the coin electro 50 and to the relay 60 , to end in the earth.

   As the relay 60 is high resistance, it attracts first, by closing its pads 61, to apply at this time the potential of 110 volts, from the two sides of the

 <Desc / Clms Page number 24>

 
 EMI24.1
 line, in order to ensure a complete functioning of llf-zlectr4 at coin 60 and of trigger Xclectro - = u.

   This last electro works in such a way as to restore the initial position of the contact springs 5 when a single piece of five
 EMI24.2
 cents was filed, while lélcctio s. coin works in such a way as to determine the rlr: boU1'se, ent of the.? Ece or coins already introduced and to restore the p02: co :. -, ir.JtiaY contact springs 6 and 7, all of a [..J .-: J ::. e bi3n known per se. It will be noted that, the conductors -L and + L of line 100 being disconnected from the other circuits of the prepaid station-
 EMI24.3
 .: SI2ty 00 coin electro receives its full potential from co #J :: and e.



  COI # ne it was indicated above, the relay - = 30 attracts when the call is established. At the end of the conversation, the calling subscriber hangs up his handset, and the. loop going
 EMI24.4
 to the relay; 36t, i opens, CO:. '.,:? 2 described above, so as to initiate the sequence of operations described above.

   The ruelais ks3Ct is kept attracted from an earth present Q; ::; pads 314 and, through the pads when the relay 220 has attracted, so as to establish a bonding circuit
 EMI24.5
 for the lower coil of relay-43C, circuit comprising the conductor 437 and the pads 436. Then, and when the, pads 222, 234 and 242 close, the cash potential
 EMI24.6
 ment of +110 volts is applied by i '* # tre # =;

  ise of the circuit described above of the electro coin, that when the
 EMI24.7
 pads 431 are open and pads 432 you eru, ès, so as to cause the attraction of the relay 60 and the engagement of
 EMI24.8
 the electro to "1> Tîe 60, for the operation of the collection, as well as the engagement of the release electro 40.



   When the pulse generator cycles
 EMI24.9
 lcti nne '"' ent, which takes place during a determined time interval, the earth is eliminated from the P2 studs, and the

 <Desc / Clms Page number 25>

   relay 240 retained so as to open, by the pads 243, the circuit going to the relay 230, which in turn drops.



   Relay 240 is pocketed to attract when the pulse generator cycles next, since the circuit of relay 250 is now open to the coin contact springs 7. Since the electros 40 and
50 operate jointly, their non-operation and the opening of the contact springs 7 have the effect of initiating a new cycle of operations, with a view to applying a coin potential to the electro coin, so that the latter performs the required manipulations for an uncashed coin.

   Relay 230 drops out, and causes relay 220 to drop out via pads 231; by the studs
232, it eliminates a bonding earth for the relay 310, and, through the pads 233, establishes a circuit for the attraction of the relay 270. The relay 220, on falling, cuts the bonding circuit {for the lower coil of the relay 430, so that the latter drops out. Before the relays 310 drops out, the relay 270 attracts in a circuit starting from the earth present on the rest pads 324 due to the triggered relay 320 and passing through the working pads 312 of the relay 310 and the pads 233, to end in the relay 270.

   This last relay, by attracting, closes by the pads 273, a circuit for the relay 330 and, by the pads 272, connects the conductor F2 to the primary of the transformer 304. The relay 330, by attracting, earths, by the pads 338, the starting wire of the tone generator and, through pads 332 and 335, connects the secondary of transformer 304 in series with capacitor 303, to the two line conductors, through the path described above .



   In prepaid substations temporarily taken out of service, the establishment of a shunt around the conden-

 <Desc / Clms Page number 26>

 sateurs of the resonant circuit described above, using a capacitor corresponding to capacitor 16 modifies the resonant frequency in such a way that it becomes that of the access prohibition pulse; to know,
6,000 periods per second.

   This coded resonant circuit will again produce the priming of the azeu-filled lines, corresponding to the tube 15, which will have the effect of a new attraction of the relays corresponding to the relay 230; however, when the access inhibition relays, which correspond to relay 120, are attracted, the circuit going to the relays which correspond to relay 110 closes at the pads corresponding to the pads 126.

   By attracting, the relay corresponding to the relay 110 opens, by pads which correspond to the pads 111, the circuit going to the prohibition relay
 EMI26.1
 access, By falling, - the a.-2ces interdicti-on relay stops the shunt established by the capacitor corresponding to the capacitor 16, so that the tuned circuit is again ready to receive a pulse of prohibition of access.
 EMI26.2
 COffi! Junicétti.Q! Lent.g.sHp.L.J2Q2te; è 1i.ê. to lillsLJ1jgrr¯e 1i-, nēprtaée a el interco:

  rFunicaton
A call of this type is initiated in the manner described for a local call to a subscriber of another line, namely, by lifting the handset and depositing the coin of the appropriate value, in order to activate the same relay, via the circuits described above, in order to attack selector 490. To reach another user
 EMI26.3
 of line fllÉ1l2, the user requesting the OJ: '! 1,6 the number zero and thus causes the selector carriage to be raised to the tenth level.

   The selector detects the return of a land (
 EMI26.4
 through driver C of a muni.r. well coi, i -., ue any, from pads whose closing is caused by the selector rest shaft contacts, with a view to pro
 EMI26.5
 Evaluate the attraction of the 4dG relay, which the island locates them;.; .1

 <Desc / Clms Page number 27>

 
 EMI27.1
 from i'agon to provide a tone I return: i '.p::,;: .. 1' through the capacitor .à1J & !, aes pins 46, -41; :; '':;: 5, 11.:=, 1 :::: ... 3 and 213, up to conductor + L, this tone being returned to the receiver of the calling user) so that the latter is infOri1.8 because an operation Lie :::. i & "1 & l1E5: t: 'C: l is in progress and it must not C have:'. l1cr le tl'f.:. :.: s ... iE Lie: l.



  Plots 44. se x .. '. Ï'Iīt'.li-t to build a c': ü'LrcJ .., .... ': i.'.? T qui pe-Sbe 'pE .l 'the COIlùUCt <= Ul', in order to maintain allu.it..5 1> lc: F. "7c occupancy 470, as well as 1 ::,:. ¯y2S C,.: C ' i: .z. .¯.¯ ..: i: cç: à1s each operator position A bonding circuit s>; established, ent.:; for relay 440 passing through, pads 373 , 411 and 444. The pads 445 establish a circuit p & s. == t per the pads 4SÔ and the conductor .2z, this circuit is .... '1t. :: e,; tinê to light the lamp 471 of the defendant station , as well as 1 ..



  Issipes which correspond to it in all the j, ixiij, is 1> + -. miss, so that these operators perceive the 8i - .. '.' 1 $ .1 ez that one of them answers the call. The circuit ..- ..lais 45C opens at pins 4. # ô, and this relay 1: 11.7e so as to open, by pins 46; and 43- ':', the loop 5 ',,:, .-' talion extending to the selector lis.ne relay, so that the latter triggers in the correct way COl1Á.ue 2l: soi. A variant col1858 circuit for relay 370 is established at pads 446..sn fell back, relay 4u0 pI't: j: l ': by flats 45.5, a circuit for relay 460, ce ùaz: .e circuit that must close when the attendant answers
 EMI27.2
 the call.
 EMI27.3
 



  The operator pushes her plug into the jack Jl, i'er, 1, jj 'thus the pads 4? 2 and earthing the conductor il, so as to close a circuit prepared previously and z> z3s ;: tlt by the pads 67 and 151, this circuit being ûCtltiné tLl M lais 460, which attracts, and closes, by the pads 46L and 403, a loop pe, ntGtrlt of the dicorde or operator cord circuit and include the conductors T and R xc ' .:,? ec'Gïvç (sltaalt, 3ea

 <Desc / Clms Page number 28>

 pads 451 and 453 respectively, to end at the secondary of the translator 402, through the pads 361 and of the rectifier 404. The operator can now converse with the requesting correspondent, through the translator
402 and a circuit comprising the loop of the prepaid station, described above.

   Through pads 462, the circuit intended to provide the ringing tone to the calling user opens and through pads 464 another bonding earth is supplied to relay 440. Relay 460 closes on its own. bonding circuit, from the earth, through the pads 374, 412 and 465, Through the pads 466, the relay 460 cuts the circuit of all the call lamps, so as to extinguish these lamps, and by pads 467 establish a circuit for the lower coil of relay 430; which attracts, and closes the pads 432, so as to prepare for the application of a collection potential to the line. At the studs
468 prepares a circuit for ensuring manual handling of the currency, which will be described below.



   The operator, if she wishes, can now change the cords without interrupting the connection, since the relays 440 and 460 are stuck by the relays 370 and 410.



   After ascertaining the number of the called subscriber, the operator invites the calling party to hang up, after which this party periodically receives a call signal, and must pick up his handset when the call signal stops ringing. When the caller hangs up his handset, the springs 1 open, so as to cause the relays 360 to drop, which in turn closes the pads 363 and establishes a circuit of an end-of-conversation lamp ( not shown), this circuit passing through the pads
376 and 434 and the conductor S, so that this lamp comes on, thus indicating to the operator that the calling party has hung up.

   Relay 410 is de-energized shortly after opening of the

 <Desc / Clms Page number 29>

 studs 362; however, the relay 420 is not energized when the pads 363 close and the pads 435 open.



   The relay 370 does not drop when the pads 413 open,, given that this relay is stuck from the pads 446.



   The relay 320 is kept energized after the opening of the pads 414, by the earth present on the pads 377, so that the relay 312 is also kept energized. It will therefore be noted that the repeater 200 cannot be attacked by another user.



     .2; given that the line has only four users and the last digit of the called user's call number indicates the call frequency assigned to him individually, the attendant now enters his call cord 510 in the J3 jack of fig.5, so as to provide the call frequency in question, in order to send a call signal to the called party.



   The operator activates the key K8, so as to apply an earth potential through wire S2, of the bots 313 and 233, with a view to the attraction of the relay 270. The latter relay prepares a circuit for sending an unblocking or releasing pulse of alternating current at 6.0CO periods to the two line conductors, through a path described above. The operation of the components of the prepaid set connected to the line will be identical to that of the sets whose operation has been described above, once an outgoing local call has been established.



   After reconnecting the sets to the line, the attendant alternately and periodically activates the key, i.e. one of the keys K4, K5, K6 and K7, individually assigned to the calling frequency of the requested user, as well. than the key individually assigned to the frequency of the calling user, so as to apply the desired call frequencies to the driver R2. Simultaneously, a land is

 <Desc / Clms Page number 30>

 applied from the first key operated on cord '10, through conductor '± 2, to relay 210, the - which attracts so as to connect conductor R2 to line wire -L, through pads 212 , and to apply a new earth to the line wire + L,

   by the pads 214, each time a call key is actuated. The calling frequencies of the requested and calling users are then sent alternately through the line -L, from the conductor R2, passing through a capacitor corresponding to the capacitor 14, and through a spring corresponding to the res-. output 3, as well as a call bell corresponding to the bell 90 and provided in each station of the shared line, with return, by the conductor -L, to end at the earth present at the studs 214, with a view to 'activate the call tones individually assigned to the frequencies provided, ring tones provided to the called and calling stations, in any well-known manner, so as to send a call signal to the called and calling parties.



   If the called party does not answer within the prescribed time, the attendant simply stops sending call signals to both users, so that the calling user goes on line again. When, at this moment, any user establishes a connection to the repeater 200, the access denial potential is not applied to the other stations, since the relay 320 is actuated in order to prevent the attraction. relay 330, so that the access prohibition circuit is kept open. The relay 360 attracts in a circuit already described, so as to cause the attraction of the relay 410. The pads 363 open, so as to cause the extinction of the control lamp, in order to inform the terminal that someone. 'one replied.

   When the person who went on line is the requesting user, the operator informs the latter that

 <Desc / Clms Page number 31>

 the called party did not answer. This user then hangs up his handset, which has the effect of releasing relays 360 and 410 and relighting the cord or control lamp, this in a circuit described above.



   The operator, if she wishes for any reason can operate at this time the test of the amount introduced. This is important in the case where the person who went on line is neither the calling party nor the called party, and asks the operator to call another line. To perform this test, the attendant inserts the plug of cord 520 into the J2 jack and closes the key K3, so as to send an earth through the conductor Tl, the pins 468 and the conductor 269, to the relay 260 The latter attracts, so as to close the pads 262 and 263. Through the pads 263, an obvious circuit is established for the relay 230, so that the latter in turn causes the attraction of the relay 220. .

   The- + L conductor, which was connected to earth by means of a circuit described above and passing through the coin-operated machine 50, is now connected, by the intermediary of pads 213 and 224, to the pads 262 and to the conductor R1. No circuit is established towards the relay 250, since the pads 261 are open. The -L conductor is likewise connected, through the pads 211, 222 and 262, to the conductor R1. If the coin contact springs 7 are closed, indicating that the coin has been inserted, an earth is sent to the conductor Rl from the conductor -L, passing through the string contacts of K1 and K2, to the battery, through the coil of relay 530.

   This last relay attracts, thus causing the closing of the pads 531, so as to determine the ignition of the induction indicator lamp. 540. Thus, the operator can perform a test for various purposes to determine whether a coin has been

 <Desc / Clms Page number 32>

 introduced, and take appropriate action. this test can be carried out at the end of an ordinary local com unication, in order to determine if the electronic control and the triggering element have worked. when the operator wishes to refund the change, she releases the key K3, thus opening the circuit to the relay 530, which has the effect of extinguishing the lamp 540; on the other hand, the operator activates the key K1.

   Earth is reapplied through conductor T1, so as to cause pulling of relay 260, and a payback potential of +110 volts is sent through conductor RI. , pads 262 and part of the electronic coin control circuit, described above, so as to actuate relays 60 and 40 and the coin operated device 50, as described above.

   If the attendant wishes, she can operate the key K1 before releasing the key K3, given that the operation of the key K1 has the effect of interrupting the circuit of relay 530. The attendant then removes her plug from the jack. J1, so as to eliminate the earth of the conductor H, by the pads 472 and causes the release of the relay 460, which in turn determines, by means of the pads 464, the dropout of the relay 440. The plug must be removed afterwards that the correspondent present on the line hangs up and after the repayment potential has been applied in the manner which has just been described, in order to prevent a collection operation from the repeater.



  The pads 467 cut a shoe shine going towards the lower coil of the relay 430; however, this relay is stuck from the pads 274. The dropout of relay 440 cuts the circuit to relay 370. The dropout of relay 370 then has the effect of attracting relay 230, as described above. Relay 220 attracts without object, since no circuit can be established towards the relay the reports

 <Desc / Clms Page number 33>

 of contacts 7 being open. Therefore, the relay 240 is not actuated. The relays 320 and 310 drop in turn, as described above. The bonding circuit for the lower coil of relay 430 is open to pads 314; however, relay 430 does not drop until relay
220 keeps the pads 226 open.

   Relay 230 drops out when pads 322 open, thereby in turn determining the release of relay 220. The access release pulse is now applied to the line when relay 270 pulls in, everything as described above.



   In the event that the called user answers the call, the relay 360 is energized in a circuit analogous to the circuit described above with regard to the station P1. The relay 410 is energized. The attendant's control lamp goes out when the studs 363 open, and the attendant stops sending the call signal. The calling subscriber, on receiving the signal which consists of the suppression of the periodic ringing, picks up his handset. When the calling party has lifted his handset, the microphone and the receivers of this party are found to be connected to the line conductors + L and-L, which establishes a circuit of conve rsion to the party standing at the phone. another prepaid set on the line.

   A reverse battery potential is sent from the left side of relay 360. The access barring pulse cannot be sent as in the case of initiating a call, since relay 320 is attracted. The operator then removes her Jlet J3 jack plugs respectively. The operator can come back online at any time to monitor the conversation, without activating any relays,
When the two users hang up, relay 360 drops out, thus causing relay 410 to drop out. Relay 410 opens the circuit via the pads 412, as described above.

 <Desc / Clms Page number 34>

 above, going to relay 430.

   The relay 460 drops out, so as to cut the circuit going to the relay 440, which in turn drops, causing the circuit to open towards the relay 370. The relay 370 drops out by opening the pads 378, so as to apply a occupant earth at the connector bench. This earth is applied at this time from the pads 315, as described above.



  The pads 372 close, so as to establish a circuit described above for the relay 230. The latter relay acts so as to cause the excitation of the relay 220 which in turn establishes a circuit described above and passing through the coin contact springs 7 of the requesting user, circuit intended for relay 250. Relays 320 and 310 are released, as described above. The relay 220 maintains the excitation of the lower coil of the relay 430, from the pads 226, through the conductor 437, after the opening of the pads 314. The relay 250 tests the payment and, if a coin has been introduced, this is cashed, as described above, at the end of an outgoing local call, after which relays 230 and 220 drop out, as described above.



   When a calling or called user remains on the line after the other user hangs up, the pulling of the relay 360 results, which prevents the repeater from performing a collection operation as long as the last user does not. did not hang up. Relay 440, which holds relay 370 in the engaged state, cannot be released until both the subscriber and the attendant hang up, since relay 440 is controlled by both. , through the contacts of the relay 460. The relay 370 maintains the junction in the energized state and, consequently, the relay 440 must be released, to release the junction.

   Thus, once the operator has answered,

 <Desc / Clms Page number 35>

 the junction is under the control of the operator and the subscriber, and the latter is not able to 'establish any communication through the' selector, being- since this cannot be attacked as long as the relay 440 remains attracted. It is understood that the attendant can move the cards without disturbing the connection, as long as the relay 360 is kept attracted by a correspondent present on the line.



   Either user, when alone on the line, can send a signal to the operator by shaking her switch hook so as to release and attract again, in a manner fast, the 360 relay, which has the result of making the operator's control lamp flicker and thus attracting the latter's attention. The operator can then go online and perform the regulatory operations requested by the correspondent on the line. It is understood that it can test the payment and carry out an operation for the collection or refund of money, in the manner already described above.

   It should be noted that a user who activates his switch hook so as to cause the operator's lamp to flicker does not risk being denied access to the line.



   Long distance calls.



   A user of one of the prepaid sets, such as the Pl set, initiates a long distance call by attacking the repeater 200 and the selector 490, as described above, and sending the digit zero to the selector, so that the latter takes its carriage step by step to its tenth position, where the rest shaft contacts of this selector return a ground to the conductor EC, in order to produce the attraction of the relay 440, as described above. The circuit going to relay 450 opens and the latter drops out;

 <Desc / Clms Page number 36>

 so as to release the selector. The relay 440 attracts, so as to send a signal to the operator, by causing the lighting of the lamp 471.

   The operator inserts her card into the Jl jack, so as to cause the attraction of the aforementioned relays 460 and 470, and talks with the requesting correspondent, In the event that there is any doubt as to the amount that the requesting correspondent has dropped off to call the operator, the latter reimburses any parts that may be found by manual intervention. in the coin hopper, before establishing the connection, this reimbursement taking place in a manner already described with regard to the reimbursement of coins in the event of an intercom call not established.

   In other words, the operator inserts the ': plug of the coin cord 520 into the jack J2 and actuates the key K3, so as to carry out the prepayment test, after which it actuates the key K1 in for the reimbursement of the amount, all in the manner described above. However, in the call of the type considered here, the 510 call cord is not inserted into the J3 jack in order to prevent access to other extensions connected to the shared line, as was the case. for an intercom call.

   The operator has the desired information provided and then establishes an interurban communication, in any well-known manner, through her dicorde, to the desired correspondent and, having entered into contact with the called party invites the calling party to introduce the appropriate amount of currency, before it establishes a conversation circuit, from the translator 402, through its dicorde, in any well-known manner.

   The operator identifies the amount deposited, thanks to the tones generated in the coin microphone 12 and transmitted by

 <Desc / Clms Page number 37>

 the Junction conductors -L and + L, the tranalator @ and the operator's receiver.



   When the attendant notices that her control lamp is on, she follows that the calling user has hung up in order to interrupt the call. By this same means, it can measure the duration of the call and go online from time to time in order to invite the applicant to introduce new documents. Noting that her control lamp is on, the attendant simply removes her plug from jack J1, so as to cause relay 460 to drop, which in turn determines the release of relay 440.

   If the operator removes his card before the calling party hangs up, relay 460, which is maintained in the attracted state by means of pins 465, 412 and 374, drops again following the release of the relay 410, so as to cause a momentary illumination of the lamp 471 in a circuit passing through the pads 445 and 446, in order to signal the release of the repeater. The relay 440 drops out immediately after the opening of the pads 464, and cuts the circuit of the lamp 471 by the pads 445. The relay 440 also causes the drop-out of the relay 370. The relay 430 is kept attracted by the relay 310. .

   This last relay begins to fall; However, relay 230 attracts, sticking relay 310 and causing the pull of relay 220, which also sticks relay 430. Subsequent operation of prepayment test relay 250 and evacuation relay currency 240 is the same as described above.



   In the case of a delayed long distance call, or the operator cannot immediately reach the called user, she invites the calling party to hang up. Qt informed him that she will call him after having touched the desired correspondent. As it has been described above about

 <Desc / Clms Page number 38>

 
 EMI38.1
 of an intercofunication call, the Ce
 EMI38.2
 nexion by the calling party has the sole effect of
 EMI38.3
 the fallout of the ôii relays; and 410, as long as the op. ratrice maintains its plug in the J1 jack.

   Therefore, the repeater 200 is glued as loL1t.r: - ,,, as the operator wishes, she can release the whole connection after having obtained the desired information, which p-rets the establishment. other coi; L unica: t3-ons by eAti <e ;;. ib # mu Leur Sue, from the nianière described above. =: 1; s5erz'ni then its plug in the il jack, when the repeater is connected, the operator causes a new attraction of the relay 460 which causes by the 4S4 pads the attraction = u relay - = 40. The rÉ? ? i # = 0 determines a new attraction of the relay ± 7î., which blocks the repeater against incoming calls.

   The relay - = S-0 is actuated from the relay - = 6.:., From Îé'µ? N to prepare 'a collection operation, r-> c # r of the extensions of the shared line cannot be seen prohibit line access i the operator had not removed his plug from the Jl jack after touching the correspondence-c. dea -.; = ndé, î & the extension of the requesting correspondent would be .Efé -The state not t; .Q'pd: 1C.U, -While the other -oostas would have remained suspended, 'erarice then introduces his file. call coraon in jack -3 and c: tDi ± n ùe one of the keys 2.4, 315, "N6 and K7, assigned individually 3.ec.ent to the call frequency of the calling party, in order to call it .

   When the latter responds, which is indicated by the fact that the relay 360 causes the extinction of the lae
 EMI38.4
 response from the operator, the latter invites the requesting correspondent to enter the required amount of change.
 EMI38.5
 



  The operator then establishes the Coin .anication using her dic orde. At the end of the communication, the coins mr) nnaie are cashed in the manner already described and the repeater 200 is released. It should be noted that the opera-

 <Desc / Clms Page number 39>

   sorted can at its own discretion establish communication to
 EMI39.1
 any of the stations connected to li, na 11 ..., 0, applying the procedure described above. incoming.calls.,
 EMI39.2
 A local subscriber such as .... 8, or an incoming long distance op <.1-a'iri> ee, can establish a connection, p [1r through a well-eo- switching device. nL1 of the type;. "t1'O \" lg81 ', such as the 3: 1i switchgear, to a connector such as the 0tJ connector.

   This last coincctc: ux 'this activates by two formed digits, so as to reachiú0.r. :: the rep0titeul' SCO and to connect to the born conductor ', to the' :: 1:) L: '¯' junction actors + The and -L'and to the conductor 3 '.



  The connector tests the absence of earth;> 61 "the braid of the conductor C ', of the pins 379 and 316 and of the lower terminal of the relay 360 ... if the connector does not meet a earth indicating that the line is occupied; the battery potential which crosses the lower coil of relay 350, actuates the direct connection relay (no
 EMI39.3
 shown) of the connector; and the c'oxzduc te ur 'is ,, is to earth} so as to cause the attraction of the relay 350 by the input of the above circuit.

   By the pads: Jj'7, relay 560 opens a point in the conductor. -I going to relay 460, and e ,, * J2'cè Empress C.Til7.TerVC ', ll.x' by an online input to activate relay 460. by the pins
 EMI39.4
 3â "5, the 3ciao relay opens a point in the circuit going to the relay:

  , 3G, and, by the pads 3d6, blocks the junction in the operator position, causing the lighting of the lamp 470 via the conductor B. The pads 352 and 354 close, so as to connect the + L 'and -L' conductors, respectively to the + L and
 EMI39.5
 -L, through the pads 2.13, 235, 334 and SU, 2S1 231, respectively.

   ! sn-tre-temps, the third digit, in-

 <Desc / Clms Page number 40>

 seen at the connector, results in the latter selecting the harmonic frequency assigned individually to the requested part to which the repeater 200 is assigned and, when the connector's direct connection relay attracts, the call frequency is sent through the driver's input -L ', of the pads 352 and of the part already described of the calling circuit, and is returned via the pads & 354 / and of the conductor + L', so as to activate the bell, corresponding to the bell 90, of the desired set and thus to transmit a signal to the requested subscriber.

   At the same time, a ringing tone is sent to the calling subscriber from the connector in a manner well known per se.



   As indicated above, the present invention is not limited to a system using a three-digit conductor, as described above, this system having been described only here in order to demonstrate the mode of operation. of the invention.

   When the called party removes his handset from the hook-switch, the ringing of the station is triggered by the contact springs 3, and an alternating current circuit is established to control the call cut-off relay ( not shown), of the connector, this circuit passing through the loop, described above of the prepayment station, from which the terminals are excluded
361, the translator 402, the relay 360 and the pads 353, but in which the pads 352 are included, as well as the conductor -L ', this circuit leading to the battery located on one side of the cut-off relay, and starting from Earth. located on the other side of this relay, through the conductor -L 'and the pads 358.

   The call cut relay attracts, and extends the loop circuit, so as to actuate the relay (not shown), intended to reverse the polarity of the condustors of the junction going to the connector; an outr, this relay establishes a conversation circuit vars

 <Desc / Clms Page number 41>

 the requesting correspondent. The two correspondents can now converse. In the meantime, earth is applied, through the conductor: ± ', by means of the direct connection relay, to the battery, through the lower coil of relay 340.

   This last relay attracts, and closes a circuit for the relay 330, circuit passing through the pads
358, 342 and 326, so that the relay 330, 320 and 310 attract in the manner described above, in order to momentarily apply a battery potential for preventing access to non-requested stations. The bonding circuit for the relay 320 is now established through the pads 358, 342 and 325, since the relays 370 and 410 are not actuated. Earth is applied by the pads 341, from the conductor EC ', so as to excite the upper coil of the relay 350. The relay 310 opens the circuit to the lower coil of the relay 350, by the pads 316. However, this last relay is kept drawn, in the debris circuit, by its upper coil.

   The relay 310 also blocks the repeater vis-à-vis incoming calls, by means of an earth sent through the intermediary of the pads 315 and 379 to the conductor C '.



   Call release is under the control of the calling subscriber, so that when the circuit to the connector line relay is cut by the calling party, the call is released. By hanging up his handset, the called party only cuts the circuit passing through the junction conductors and ending. to the reverse polarity relay forming part of the connector. The called subscriber cannot send a signal to the operator. When the calling party releases the communication, the earth is removed from the conductor EC ', so as to de-energize the upper coil of relay 350, as well as the coil of relay 340. Relay 350 drops out.

 <Desc / Clms Page number 42>

 
 EMI42.1
 ue [10 <:. 11101'13 a cvn¯1; r le.

   Cil '(,. 1. V "ns 1'., 2 '-... ¯, -., 1 ,,, é :: 1-ll, .lq; e les !! 1ot.;..:, .a. Cu relays C01.H8ctu in Of. Gr. '. d. 1-lOUV:' <..! the station circuit Si y2''ßa.7.Ifo3Flt at tT'vl :: c '' =, ll, ''. '.é: <- 2 and' u '"1J.' '' b, 30, p, r 1-s ¯.lots;, 51 and 3 Lc> shine -.-, 0 ne flat not attract; etUj1t: .011ne <l11 '?, lor ::: quc le rl..is, .J0 relets it establishes a towards the râlais & 0, which causes 2' Gttr'action of the. relay '220 which, at an turn, cut the eyelash :. unit par- the plots .- '21. The LoO relay performs a paJ.3f: .s ::. test however, con.:.e no part is present!' 81but does not pull and, Cor :: f'e relay 32u drops, relay 230 drops out thus allowing relay 270 to attract, in order to send an end of suspension pulse, as - cr above.

   Relay 310 does not drop until a payment test has been performed so that repeater occupancy is signaled both to lamp 470 in the operator position and to driver C '. leading to the connector bench.



   In the case of a call with "telephone call notification", communication must be established through the operator having access to the repeater 200 from a jack such as the Jl jack; this is for the reason that the operator must control the communication by means of his dicorde.



  Noticing that the busy light 470 is off, the attendant inserts her plug into: the Jl jack, so as to cause the attraction of relay 461, relay 440 attracts to in turn cause the attraction of the relay 370. Relay 430 also attracts, in order to prepare for the operation
 EMI42.2
 dler-caiseeiiient. The attendant then inserts the plug of her iG call cord and, as all the sets have access to the line again, the attendant only activates her own key, to send a signal to the called user.



  C .. last by answering, activates relays 360, 410, 330.
 EMI42.3
 320 and 310, as described above. It is understood that

 <Desc / Clms Page number 43>

 
 EMI43.1
 relay 320 drops out .rltCtl'd7.wüelilerlt, In this case, the call is established when a called User enters his own currency, as was the case for delayed long distance calls. In the following, the communication is released and the coins are cashed in the manner described above.



   The invention has been described in detail, but it is understood that it is nevertheless susceptible to various modifications and variants which may come within its scope.
 EMI43.2
 r, Ui V Jii N D x C A T '1 0 Ij b
1.- Telephone system characterized in that it comprises: a shared two-wire line, connected to a central and to which several stations are connected; means provided at each station and intended to connect this station to the shared line and to disconnect it from the latter;

   means provided in this exchange and which, under the effect of the initiation of a call from one of the aforementioned stations, are actuated so as to apply an alternating current of a given frequency to said line, said means First mentioned, acting in such a way that when the aforesaid alternating current is applied to the line, they disconnect all poles from the line except the calling station;

   means provided at the exchange and intended to then apply to this line an alternating current of another frequency, the arrangement being such that, under the effect of the application of said current of the other frequency, to the aforesaid line, the means named in the first place reconnect to the line the sets which had been disconnected from it.

** ATTENTION ** end of DESC field can contain start of CLMS **.


    

Claims (1)

2.- Telephone system characterized in that it comprises: a line to which several stations are connected <Desc / Clms Page number 44> telephone; a relay provided at each of these stations; means controlled by each of these releis, when the latter is actuated in one direction, so as to disconnect the station in question from said line and to connect this station to the line when this relay is actuated in another direction; means for applying alternating currents of a first or a second of the two frequencies to said line; means provided in the aforementioned telephone sets and which, under the effect of the application of the aforesaid alternating current of the first frequency -determine the actuation of the aforementioned relay in said first direction, but that, under the effect of alternating current above of the second aforementioned frequency, they determine an actuation of the above relay following the second aforementioned meaning. 3. - Telephone system characterized in that it comprises: a line to which several stations are connected; prepaid; a relay provided at each post in advance; means controlled by each relay, in the direction of disconnection of the corresponding prepayment station from the aforementioned line when this relay is actuated in a first direction, and so as to connect this prepayment station to the line, when this relay is.actuated according to the second sense; means for applying to said alternating currents of a first or a second frequency; means attached to these prepaid stations and which, under the effect of an alternating current of the first above frequency, act in such a way as to actuate the above relay according to the first above-mentioned direction, while, under the effect of the aforementioned alternating current of the aforementioned second frequency, determines an actuation of the above relay in the second south direction. 4. - Telephone system, characterized in that it comprises: a series of prepaid stations having in common <Desc / Clms Page number 45> provided with a bifilar shared line, by which wires are connected to Him central; means for ensuring the secrecy of communications to a user of any of the aforementioned prepayment pacts; when this user initiates a call from this station, these means comprising, to. each prepayment station, a relay and a positioning circuit for it; means provided in the aforesaid central office and which, under the effect of the initiation of a call from the aforesaid line, apply to the latter a first current of a first frequency; means' provided in the aforementioned .en position setting circuits and which, under the effect of the first current above, are controlled such that, in, all prepaid stations connected to the shared line, except in. the set which initiated the call, the relays assigned to these sets are positioned so as to disconnect the corresponding prepaid sets from the aforementioned line., the arrangement being such that, at the end of a call, the aforementioned means, provided at the aforementioned central, act so as to apply to the line a second current of another frequency, while the means interposed in the aforementioned control circuits are controlled, under the effect of the aforesaid second current, in such a way that the relays which are assigned to them are put in position so as to reconnect to the above line all the aforementioned prepaid stations which had been disconnected from it. 5.- Telephone system characterized in that it comprises: a series of prepayment stations connected to a two-wire line which terminates in a central; means provided in this exchange and intended to apply an alternating current of a first frequency, to this line, following the initiation of a call originating from said line or to the latter, and to apply at the above-mentioned line <Desc / Clms Page number 46> te a second alternating current, of another frequency, has EMI46.1 the end of a communication comprising the above-mentioned link> 1; 5; the means provided for each of the prepayment stations listed below. above and comprising a series resonant circuit tuned to said first frequency; a first, a sec .nd and a third relay; means for tuning the aforesaid resonant circuit to the second piecite frequency, as well as a cold cathode gas discharge tube and three electrodes, this gas discharge tube being called to actuate the aforesaid first relay to following the detection of a voltage at the terminals of the aforementioned resonant circuit, under the effect of the above first frequency, the first relay in question acting so as to cause the operation of the aforesaid second relay, which causes the momentary suspension of the considered prepayment station and acts on said means so that they tune the resonant circuit in question to the second above frequency, the arrangement being such that said gas discharge tube , the aforesaid first relay and the resonant circuit tuned above act so as to actuate the aforesaid third relay in the direction of putting the prepayment plste in question back into service, after the appearance of the aforesaid second frequency. 6.- Telephone system characterized in that it comprises: prepayment stations connected to a two-wire line which terminates in a central and provided with devices for receiving a coin inserted and for removing this coin; means for ensuring the secrecy of communications, by ensuring that several of the aforementioned prepaid stations cannot simultaneously use the aforementioned line; these means comprising a device provided at the aforesaid exchange and intended to apply to the aforesaid line one of the two frequencies of <Desc / Clms Page number 47> alternating current; the dispsiation being such that the aforesaid first frequency temporarily puts the aforementioned prepaid sets which do not transmit or receive a call out of service, as well as a second frequency acting so as to reconnect the prepaid sets which are connected to the line in question. had been temporarily put out of service, the second-mentioned means comprising, in each prepayment station, a tuned resonant circuit which is influenced by the alternating current of the. aforesaid first frequency when the prepayment station in question 'is' connected to the aforesaid line, but which is influenced by the alternating current of said second frequency when the considered coin-operated station is momentarily taken out of service, said second-mentioned means also comprising a gas discharge tube and a rail which, as a result of the voltage which appears at the terminals of a part of the aforementioned resonant circuit under the effect of the non-application of said alternating current of the aforementioned first frequency, cause the excitation of a momentary suspension relay in each prepayment station which neither transmits nor receives a call, so as to guarantee the confidentiality of communications to the user of the prepaid set in question; while, under the effect of a voltage which appears at the terminals of a part of the above resonant circuit, under the effect of the second considered frequency, the aforesaid gas discharge tube and the aforementioned relay act in such a way to put each of said temporarily suspended prepaid stations back into service at the end of the call in question. 7.- Telephony system comprising: a series of prepaid stations with a two-wire line terminating in a central; means provided in the aforesaid central and intended to apply to the line considered 'a. <Desc / Clms Page number 48> alternating current of a first frequency, when initiating a call to the offset or to the lines above, and applying an alternating current of one sec. frequency on the aforementioned line at the end of a call; means provided at each of the aforesaid prepaid stations and comprising a series resonant circuit, tuned to the aforementioned first frequency; a first, a second and a third relay; means for tuning the above resonant circuit to the said second frequency; and, a transistor, said transistor acting so as to actuate the aforesaid first relay following the detection of a current at the terminals of the aforementioned resonant circuit, the first relay above acting so as to actuate the aforesaid second relay to all the aforementioned prepaid sets, other than the calling or requested prepaid set, so as to disconnect the prepaid sets in question from: the aforesaid line and to tune the aforesaid resonant circuit to the aforementioned second frequency, thus ensuring the secrecy of communications to the user of said requesting or requested prepaid stations, the arrangement being such that the aforesaid transistor, said resonant circuit tuned and the first relays above act so as to actuate the aforementioned third relay so that the latter puts said prepayment stations back into service, after the application of the second frequency above, to the line in question. 8.- Telephone system comprising: a shared line to which several telephone sets are connected; means provided at each telephone set and intended to connect the sets in question to the shared line and to disconnect them from it; means for applying alternating currents to the aforesaid line; means comprising a transistor and resonant circuits, provided <Desc / Clms Page number 49> to each of the aforesaid telephone sets and intended to detect the presence of the aforesaid alternating cables and to amplify them, the amplified current acts acting so as to determine the operation of the means mentioned above in the first place , in the sense of connecting the set in question to the aforementioned line or disconnecting it from the latter. 9. - Telephone system comprising: a telephone set connected to a line; an auxiliary equipment provided at the aforesaid station and influenced by alternating currents of determined audible frequencies and of an intensity considerably greater than the level of the transmitted speech; means for applying to the aforesaid line alternating currents of determined frequencies, of a level slightly higher than the level of the speech transmitted by this line; and, a transistor amplifier provided in the telephone plague in question and intended to amplify the above alternating currents to an intensity sufficient to operate the above auxiliary equipment. 10. A telephone system as specified in claim 9, characterized in that it comprises means controlled following the actuation of the aforesaid auxiliary equipment, so as to selectively connect the aforesaid station to the line in question and to selectively disconnect this station from said line. 11.- Telephone system characterized in that it comprises: a central; a series of post-telephone calls; a two-wire line connecting the aforementioned telephone sets to the aforementioned exchange; an auxiliary device assigned to each of the telephone sets, each of these devices comprising a pre-determined operating cycle, so as to connect the set which is to it <Desc / Clms Page number 50> assigned to the aforementioned line and to disconnect this set from it; a tone generator device provided at the aforesaid exchange; means which, following the initiation of a call from one of the aforesaid telephone sets, momentarily apply to the aforesaid line a given frequency from the above tone-generating device and which, following the release of the call, momentarily apply, to the line above, another frequency from the said device generating this tone; and, intermediate means in the auxiliary apparatus assigned to each of the non-calling telephone sets, forming part of the line. above, the arrangement being such that when the aforesaid tone generator device is momentarily connected for the first time to the line in question, these latter means control the auxiliary equipment assigned to this line so that this equipment performs a part of the aforesaid determined cycle, in order to disconnect the non-calling telephones considered, from the above line, while, when the tone generating device in question is connected a second time to the above-mentioned line, said means control the auxiliary equipment assigned to this line, so as to activate this equipment during the remaining part of the cycle determined above, with a view to reconnecting the non-calling telephone sets considered; to the line above. 12. A telephone system as specified in claim 11, characterized in that the aforesaid calling telephone set comprises means for preventing the auxiliary equipment assigned to the latter station from fors tioning in the aforesaid determined cycle, at the following the connection and reconnection of said tone generator device to the aforesaid line. <Desc / Clms Page number 51> EMI51.1 l, â.- ùyst8we of C81'LCtéI'isG telephony in that it comprises: a central; a series of telephone sets; a two-wire line connecting the aforementioned central to the aforementioned posts; an auxiliary device assigned to each of these telephone sets, each of the aforementioned devices comprising an operating cycle, in order to connect the telephone plague which is assigned to it to the aforementioned line and to disconnect said set from this line ; a tone generator device provided at the aforesaid exchange; means which, during the routing of a call to one of the aforementioned telephone sets, act so as to connect the tone-generating device in question to the target line, and which, under the effect of the release of the call aforesaid, act so as to momentarily reconnect the aforementioned tone generator device to the line in question; and, means forming part of the auxiliary equipment provided at each of the non-calling telephone sets forming part of the line in question, means which, under the effect of the first application EMI51.2 momentary current of a first. :: frequency, by the above tone generator device, on the line considered, control the auxiliary equipment of these non-calling telephone sets, in such a way that this equipment is actuated during part of the cycle determined above, so as to disconnect the non-calling telephone sets considered from the line in question, while, under the effect of the application of a current of another frequency ,. from the aforementioned tone generator device, to the line in question, these latter means damage the auxiliary equipment assigned to the non-calling stations above, so as to activate this equipment during the remaining part of the aforementioned determined cycle, in order to connect again the non-calling telephone stations considered to the line in question . <Desc / Clms Page number 52> 14.- Telephony system as specified in claim 13, characterized in that the aforementioned request station comprises means to prevent the auxiliary equipment, which affects it, to operate during the cycle determined above, under the effect of the connection. aforementioned and the aforementioned reconnection of the tone generator device in question to the line in question. 15. - Telephone system characterized in that it comprises: a shared line, a series of telephone sets connected to this line; a tone generation device, capable of generating a first and a second tone; means for momentarily applying the first aforesaid tone to the line in question, following the initiation of a call from a telephone set connected to the above line or the establishment of a call. a call to this extension; means for momentarily connecting the aforementioned second tone to the aforementioned line, following the release of a call to or from a telepiioiiic station connected to the line in question; means provided in each telephone set and which, under the effect of the first aforementioned tone, are blocked in relation to the line, while they are connected again to the line in question following the application of the aforementioned second tonmlimé in the line above; means provided at each telephone station.; ic and acting in such a way that, when this station is calling or requested, they render inoperative the blocking means of this station, the aforementioned blocking means comprising a tone filter, an amplifier with transistor, a first electromechanical device, operated by a current amplified by the above transistor amplifier; a second electromechanical device, the above tone filter allowing the passage of the above-mentioned first tone to the amplification <Desc / Clms Page number 53> in question, when the second electromechanical device above is not actuated, while this filter allows the passage of the second tone above to the amplifier considered, when the aforesaid second electromechanical device is actuated, the arrangement being such that when the second electromechanical device in question is actuated, it prohibits line access to the telephone set to which it is assigned, while, when this second electromechanical device is released, it connects again to the line the telephone set to which it is assigned, with this that the first aforesaid electromechanical devices are actuated in each of the non-calling or non-called telephone sets, under the effect of the momentary application of the first tone above to the aforesaid line, so as to actuate the second aforementioned electromechanical devices, in such a way that they block the aforementioned non-calling or non-calling stations, with a view to ensuring the secrecy of communications to the aforementioned calling or called stations, the arrangement further being such that in each blocked telephone station, the first electromechanical device above acts, after the 'release of a call by a calling or called telephone set connected to the line in question, and under the effect of the momentary application of the aforementioned second tone to the aforesaid line, so as to bring about the release of the second electromechanical device above, to cause the blocked telephone sets in question to connect to again to the line in question, so that said stations temporarily out of service can once again have access to the aforesaid line.