US2020466A

US2020466A - Telephone system

Info

Publication number: US2020466A
Application number: US689192A
Authority: US
Inventors: Hatton William; Leslie B Haigh; Jean R A F Escande
Original assignee: Western Electric Co Inc
Current assignee: AT&T Corp
Priority date: 1932-09-29
Filing date: 1933-09-13
Publication date: 1935-11-12
Anticipated expiration: 1952-11-12

Description

7 w. HATTON :1- AL Nov. 12,1935.

' TELEPHONE SYSTEM Filed Sept. 15, 19:5

5 Sheets-Sheet 1 57W- WHATTON INVENTORS L. B. HA/GH J. RAFESCANDE AT7DRNEV Nov. 12,1935. w. HATTQNET AL 2,020,466 '7 TELEPHONE SYSTEM Filed Sept. 15. was s Sheets-Sheet 2 W. HA TTON INVENTORSI L.B.HA/GH JRAEESCAND A TORNE Nov. 12, 1935. w HATTQN ET A 2,020,466

TELEPHONE SYSTEM Filed Sept. 13, 1933 3 Sheets-Sheet 3 (HA Tm/v INVENTORS L.BHA/GH JRAE ESCANDE TTORNE I Patented Nov. 12, 1935 PATENT OFFICE TELEPHONE SYSTEM William Hatton, Leslie B; Haigh, and Jean It. A. F. Escande, Paris, France, assignors to Western Electric Company, Incorporated, New

York, N. Y., a corporation of New York Application September 13, 1933, Serial No. 689,192 In France September 29, 1932 15 Claims. (o1. 179-631) V This invention relates to telephone systems and more particularly to automatic or semi-automatic systems comprising coin-box stations.

It is the object of this invention to provide improved means for allowing coin-box subscribers to establish automatically calls requiring different charges, to provide improved means for effecting the collection or refund of deposited coins, and to provide improved means for preventing fraud and for simplifying the coin collecting or refunding operation on calls completed through a toll operators position.

According to one feature of the invention a record of the number or value of coins inserted at a coin box station is automatically set up at the central office and subsequently compared automatically with charge indicating signals in accordance with the value of a completed call, means being provided for breaking down the connection in case the deposited coins are insufficient to pay for the call. 7

According to a, further feature the calling line is short-circuited during determination of the charge to be made.

According to another feature of the invention an operator is informed, on calls completed through a manual toll switchboard, -of the value of inserted coins by signals which cannot be simulated by the operation of the receiver hook. According to this feature of the invention visual and audible indications are given to the toll operator, in accordance with the value of inserted 001115.

According to another feature of the invention an operators position is provided with means for transmitting voice frequency signals to selectively effect the automatic collection or refund of coins inserted at a calling station. 7

These and other features of the invention will be appreciated from the following description of one embodiment of the invention which is shown schematically in the drawings which form a part of this specification. The invention is, however, not limited in its application to the particular system which is disclosed in the drawings.

Referring to the drawings,

Fig. 1 represents in schematic form a coin-box subscribers station SI and line LI, 3, line-finder switch LF, a first selector switch SSI, a conn'ector switch CSI. and another subscriber's sta- 7 tion S2; Fig. 1 also shows in schematic form Figs. 2 and 3 represent schematically the line circuit and apparatus individual to the line LI including apparatus for use in determining the charge of a call as compared with the amount of money in coins deposited in the coin-box of 5 station SI and including apparatus for collecting or refunding the deposited coins as required in any given case.

The subscribers station SI and S2 are of the type generally employed in common battery tele- 10 phone systems, a dial or other impulse sender being provided for use in controlling the operation of the selector and connector switches employed in establishing a desired connection. The

station SI includes coin-box apparatus compris- 15.

ing coin collect magnet II, a coin return magnet I3, contact 15 which represents a system of contacts which are collectively actuated by 'a coin as it passes through the coin box a number of times characteristic of its value, and a con- 20 tact I9 which is closed when a depositedcoin comes to rest temporarily awaiting collection or return. The system of contacts actuated by the passage of a coin may be similar to that disclosed in the patent to Goodrum, No. 1,137,399, granted April 27, 1915. The box is arranged to take coins of 10, 20 and centimes. The coin actuated contacts, represented by contact I5, are operated by the passage of a coin to ground the line conductor 22 once for a 10 centime coin, twice for a 20 centime coin, and five times for a 50 centime coin. The line circuit, to which the line *LI connects at the central office, includes line relays I23 and NH, cut-off relay I09, coin identifying relays MI, I42 and I43, a rotary stepby-step switch SM, metering relay I25, a, toll call supervisory relay 34 and toll call control relays 4| to 48 inclusive; The circuit also includes a number of auxiliary control relays and a thermostatic relay I I5.

The line-finder, selector and connector switches, which are each represented by a set of brushes and a single set of terminals, may be similar in operation to those shown and described in the patent to Hatton et al. No. 1,831,387 45 granted November 10, 1931. The line-finder LF and first selector SSI form a link circuit which is represented by the supervisory relays 2H, 2I3

r and 2M, the control relays 2I2 and 2 I5, the zone relays ZI'I and 2I8; and a metering switch MS. 50 The link circuit may be similar to that shown in Fig. 15 of the drawings, and described in the 7 times.

ment is arranged to collect or return the coin deposited at a calling subscribers station. To

this end the cord C includes a coin collect key 5!, a coin return key 62 and auxiliary relays 63 and 64 which control the connection of three alternating current generators 65, 66, and 61 for variously operating voice frequency relays in the line circuit of a calling subscriber, the necessary control conditions for connecting a coin collect or coin refund potential to the calling line,

upon termination of a connection, being established by these voice frequency relays. The sleeve relay 52 operates when plug 5| is inserted in the jack of a trunk thereby lighting the supervisory lamp 55. The supervisory relay 54 is connected to the ring conductor of the plug so as to respond to supervisory signals when the subscriber answers or deposits coins as instructed by the operator. L

Assuming that the subscriber at station SI, desires to originate a call, coins equal in value to the charge for the desired connection are deposited, in the coin box, before removing the receiver. Each coin as it passes through the box to its preliminary resting place closes the contact I5 a number of times characteristic of its value to cause the operation of the line relay I23 of the associated line circuit a corresponding number of traced from battery through its winding, left back contact of relay I03, inner left back contact of relay I63, conductor 22 'of line LI to ground at contact I5 of the coin-box at station SI. The

operation of relay I23 closes an obvious circuit for operating relay I 22 and a circuit from battery through the winding of relay I04, left outer back contact of relay E69, right front contact of relay I23, conductor i253, inner back contact of relay I62, inner left back contact of relay I24, to ground at thermostatic relay l I 5. Relay I04, operated by the current in this circuit, closes a holding circuit through its inner front contact and the back contact of the magnet I50 of switch SM to ground at its own outer front contact. When relay I23 releases due to the opening of contact I5 at the coin-box, the magnet I50 of switch SM is energized in a circuit from battery through the left winding of this magnet, neXt-to-the-outer front contact of relay I04, back contact of relay I23, conductor I29, thence to ground at relay II5 as hereinbefore traced. The operation of magnet I50 opens the holding circuit for relay I04, and the release of relay I34 opens the circuit through the winding of magnet I50. The switch SM is thus advanced by the cooperation of relay I 04 and magnet I50 in response to each impulse received by relay I23, to a position corresponding to the value of the coin or coins deposited at the subscribers station.

Having deposited the coins, the subscriber removes the receiver, thereby closing a circuit from battery through the winding of line relay I23, thence to' conductor 22 of line LI as hereinbefore described, through the lower contact springs of the dial I 6 at station SI, transmitter I'I, lower front contact of the receiver-hook switch, right winding of induction coil I8, back over conductor 2| of line LI, inner right back contacts of relays I69 and I63, outer left back contact of relay I06,

' inner right back contact of relay I63, through the winding of relay I6I to ground. Relays I23 and I6I are both operated by the current in this circuit. Relay I6! closes an obvious circuit for op erating relay I62 and relay I23 again closes the circuit for operating relay I04. Relay I62 locks terminal 2 and brush I52, right inner front con- The circuit for operating relay' I23 is through its left front contact and the off-normal terminals and brush of bank I5I of switch SM and opens the operating circuit of relay I04. With relay I62 operated, relays I4I, I42 and I43 are variously operated according to the position to 5 which the switch SM is advanced as hereinbefore described. If the switch SM is in off-normal position 2, relay MI is operated by a circuit from battery through its upper winding, off-normal tact of relay I62, to ground at the inner left back contact of relay I63; relay I4I looks through its inner upper front contact and the inner upper back contact of relay I43, over conductor III to ground at the left front contact of relay I23, neither of relays I42 or I43 being operated in this case. If switch SM is advanced to off-normal position 3, relay MI is operated by a circuit from battery through its lower winding, off -normal terminal 3 and brush I52, thence to ground at the inner left back contact of relay I63. The operation of relay I4I with switch SM in position 3, closes a circuit for operating relay I43; this circuitis traced from battery through the winding 7 of relay I 43, inner lower front contact of relay 25 MI, off-normal terminal 3 and brush I52, thence to ground at the inner left back contact of relay I63. Relay I43 looks through its inner upper front contact, over conductor I I I to ground at the left front contact of relay I23. If switch SM is advanced to off-normal position 8, relay I42 is operated due to the energization of its left winding in a circuit through off-normal terminal 8 and brush I52 to ground at the inner left back contact of relay I63; relay I42 locks through its inner left front contact, the inner upper back contact of relay I 43, over conductor I II to ground at the left front contact of relay I23, neither of relays I M or I 43 being operated. If switch SM is advanced to off-normal position 6, relay I42 is operated due to the energization of its right winding in a circuit through off-normal terminal 6 and brush I52 to ground at the inner left back contact of relay I63. The operation of relay I42 with switch SM in position 6 closes a circuit through 45 the inner right front contact of this relay for operating relay I43; and relay I43 looks as hereinbefore described. The operation of either of relays H or I42 closes a circuit for operating relay I44, from battery through the winding of '50 relay I44, the outer right front contact of relay I62 to ground at the upper front contact of relay IM or to ground at the outer left front contact of'relay I 42. In the arrangement shown, there is no tariff corresponding to the first, fourth, fifth, 55 seventh, 'ninth or tenth off-normal positions of switch SM, and if switch SM is advanced to any one of these off-normal positions relay I44 is operated due to the energization of its winding in a circuit through the outer right front contact of relay I62, theparticular one of the off-normal terminals with which'brush I52 is in contact, and through the inner right front contact of relay I62, toground at the inner left back contact of relay I63. 'Relay I44 closes a locking circuit through the outer right back contact of relay I03, its own left inner front contact, to ground at the backbontact of relay I60.

The aforementioned operation of relays I6I and I62 closesa circuit for operating the group connects ground to the start lead I'I I whereby one or more idle line-finders such as LF are set in operation. When a finder LF finds and seizes the terminals to which line LI and the associated line circuit are connected, the cut-off relay I09 is operated due to the energization of its winding in a circuit through brush 203 of the linefinder switch. The operation of relay I09 disconnects relays I23 and I6I from the line LI,

opens the holding circuit for relay I04 and connects a holding ground to 'its outer left front contact to conductorIlI in place of the ground at the left front contact of relay I23. 5 The release of relay I6I closes an obvious circuit for energizing the right winding of relay I63. Relay I63 operates, disconnects the winding of relay I03 from the incoming test conductor '33, disconnects the hunting potential from test conductor 26 and releases group rel'ay I10. The release of relays "SI and I04 closes a circuit for operating the magnet I50 of switch SM whereby this switch is advanced to normal; this circuit is traced from battery through the left winding of magnet I50, outer right back contact of relay I04, interrupter contacts of magnet I50, outer right back contact of relay I 2| outer left back contact of relay I24, neXt-to-the-inner right front contact of relay I62, to ground at the left back contact of relay I6I. Relays I4I, I42 and. I43, if operated, are held operated by the ground connected at the outer left front contact of relay I09 to conductor III. Relay I62 releases as soon as switch SM reaches normal position.

When the line-finder LF finds the terminals to which line LI is connected, the windings of relay 2 II are connected through brushes 2M and 202 to conductors 2| and 22 thereby operating relay 2| I. cuit for operating relay 2I2. An idle registercontroller (not shown) is thereupon associated with the link circuit, the subscriber receives a dial tone, the called number is dialed, the zone relays 2II and 2 I8 of the link circuit are operated in accordance with the zone within which the called line is located with respect to the calling line as indicated by the office code registered in the register-controller, the connection is completed by the operation of switches SSI and CSI, and the called station is signalled by ringing 1 current all in the'manner described in the aforementioned patent to I-Iatton et a1. 1,831,387. When the call is answered by the removal of the receiver at the called station, the ringing circuit is opened and the supervisory relays 2I3 and 2I4 are connected to the called line. The operation of relay 2I4 closes an obvious circuit for operating relay 2I5. Relay 2 I5 locks under control of relay 2I2 and closes a circuit for operating the stepping magnet 220 of the metering switch MS; this circuit is traced from battery through the winding of magnet 220, brush 22 I and normal terminal, right outer front contact of relay 2I5,'to ground at the springs of cam 226 of timing switch TS. The operation of magnet 220 advances the brushes 22I and 222 to the first oifnormal position thereby placing the stepping magnet 220 under control of interrupter 223 so that the brushes continue to advance step-bystep until they again reach normal position. The aforementioned operation of relay 2 I5 also closes an obvious circuit for operating the start relay 225 of the timing switch TS whereby the driving magnet (not shown) of the timing switch is placed under control of, timed impulses from a clock CL. The timing switch is thus advanced The operation of relay 2II closes a cirat a constant rate as long as relays 2I5 and 225 remain operated. The springs of cam 226 of the timing switch are opened as soon as the timing switch begins to advance and are closed again at the end of three, six, nine and twelve minutes, each three minute period constituting a conversational unit for charging purposes in a zone metering system.

a During the advance of switch MS an impulse circuit is closed from battery, through brush 222 and the various off-normal terminals, and contacts of zone relays 2II and 2I0, through'brush 204 of line-finder LE to the winding of metering relay I25. Relay I25 is thus operated a number of times corresponding to the value of the established connection. The relation between the various charges and the metering impulses transmitted by the operation of switch MS is as follows:

Coin value Metering in centimes signals I32, right back contact of relay I26, inner left front contact of relay I25, winding of relay I 24, over conductor III to ground at the front contact of relay I09. I24 closes a short circuit through its right front contacts across the conductors 2| and 22 of line LI to prevent conversation until the switch SM has responded to the metering impulses and a comparison made between the coins deposited and the required charge. Relay I24 also closes an obvious circuit for reoperating relay I62, and opens at its outer left back contact the restoring circuit for switch SM. With relay I24 operated, a circuit is closed by interrupter I30 for operating relay I 2| this circuit is traced from battery through the winding of relay I2I, conductor I3I, outer left front contact of relay I24, through the inner left back contact of relay I26, and through interrupter I30 to ground. Relay I2I closes a holding circuit for relay I63, from battery through the left winding of relay I63 and the inner right front contact of relay I2I, over conductor I3I to the ground at interrupter I30. Relay I2I also closes a circuit from battery through its winding in series with the winding of relay I26, through the inner left front contact of relay I2I, left back contact of relay I02, right back contact of relay I06, conductor III, to ground at the front contact of relay I09. Relay I26 operates in series with relay I2I as soon as interrupter I30 opens the connection to ground.

Relays I2I and I26 are now locked in series independent of the continued operation of relay I09 due to the connection of ground through the outer left front contact of relay I26 through the left back contact of relay IOI to conductor III. After relay I26 operates, relay I24 remains operated due to a holding circuit which is traced from battery through resistance I32, inner left front The operation of relay 40 contacts and winding of relay I24, over conductor I I I to ground at the outer left front contact of relay I09 and, through the left back contact of relay ml, to ground at the outer left 5 front contact of relay I26. After an interval of time sufiicient for relay I25 to have received the maximum number of metering impulses, ground is again connected through interrupter I30,

thence through the inner left front contact of- 10' relay I26 and the left inner front contacts of relay I24 to short circuit the winding of relay I24 and thus cause its release. The release of relay I24 opens the short circuit across line LI If the number of metering impulses, as indi- 157 cated by the position to which the brushes of switch SM are advanced, does not correspond with the value of the coins deposited, as indicated by relays I4I, I42 and I43, a circuit is closed through brush I53 for operating relay I06;

20;; but if the position of switch SM does correspond with the value of the deposited coins there is no circuit for operating relay I06. Assume first that the deposited coins do correspond in value with the required charge for the call so that relay I06 25., does not operate. If the conversation terminates at or before the end of a three minute interval after the first metering impulses were received, the release of relay 2i I causes the release of relay 2I2. The release of relay 2I2 causes the release 30;. of relay I 09 of the line circuit and the restoration of the line-finder and selector switches to normal as described in the aforementioned patent to I-Iatton et al. No. 1,831,387. The release of relay I09 closes a circuit for operating the coin-collect 351: magnet I3 at station SI; this circuit is traced from the alternating current source I35 through the rectifier I35, the outer left front contact of relay I2I, winding of relay I60, inner right front contact of relay I63, outer left back contact of relay I06, inner right back contact of relay I03, inner right back contact of relay I09, conductor 2| of line LI, right winding of induction coil I8, upper normally closed contacts of the receiver-hook switch through the winding of 45' coin-collect magnet I3 and rectifier I4 to ground at coin contacts IS. The coin-return magnet II does not operate since its winding is connected in series with the rectifier I2 which is oppositely poled to the rectifier I4 with respect to line con- 50. ductor 2|. Relay I of the line circuit also operates thereby connecting ground through its front contact and the inner right front contact of relay I2I to hold relay I2I operated and to short circuit and thus cause the release of relay 55 I26. With both relay I09 and relay I26 released,

there is no holding ground connected to conductor III so that each of relays I4I, I42 and I43 releases, if previously operated. With relays MI and I42 normal and with relay I60 oper- 60 ated, relay I 44 releases. When contacts I9 open the coin collect circuit due to the coins being collected, the magnet I3 and relay I60 release. The release of relay I60 causes the release of relays I2I and I63. The release of relay I2I closes the 65 above described circuit for operating stepping magnet I50 to return switch SM to normal. When switch SM reaches normal, relay I62 releases and the line circuit is now normal awaiting another call.

70 To illustrate the circuit operations which result when the coins deposited do not correspond to the required charge for the call, assume that 20 centimes were deposited by the calling subscriber, relay I4! alone of relays I4I, I42 and 75 I43 having been thereby operated as hereinbefore described. If 30 centimes should have been deposited, as indicated by the receipt of two metering impulses by relay I25 and the consequent advance of switch SM to position 2, a circuit is closed from battery through the winding 5 of relay I06, the uppermost back contact of relay I43, terminal 2 and brush I53 of switch SM, right back contact of relay IOI, conductor IIO, outer right front contact of relay I2I, inner back contacts of relay I24, to ground at thermostatic relay H5. If 60 centimes should have been deposited, switch SM is in position 3 and the circuit for operating relay I06 passes through the outer lower front contact of relay MI in parallel with the lowermost back contact of relay I43, and in parallel with the outer right back contact of relay I42. If 80 centimes should have been deposited, switch SM is in position 5, and the circuit for operating relay I06 passes through the inner right back contact of relay I42 and the outer upper front contact of relay I43 in parallel. Similar circuits are provided and may be easily identified for operating relay I06 for all other possible cases where the required charge, as indicated by the position to which the switch SM is advanced in consequence of the metering impulses received by relay I 25, does not correspond to the value of the deposited coins. Relay I06 looks through its right front contact to ground at the front contact of relay I22 and causes the release of relays IZI and I26; and the release of relay I 2| causes the switch SM to be advanced to normal as hereinbefore described. The operation of relay I06 also opens the talking connection by disconnecting line conductor 22 from the terminal with which brush 202 of line-finder LF is in contact. The operation of relay I06 also connects the tone source I01 through condenser I08 and the inner left front contact of relay I06 to line conductor 22, thereby transmitting a tone to the calling subscriber to indicate that he has failed to deposit the required value of coins.

The opening of the connection over line conductor 22 initiates the release of the line-finder and selector switches and their restoration to normal. Relay I09 releases thereby closing a circuit for reoperating line relay I23; this circuit is traced from battery through the winding of relay I23, left back contact of relay I 03, inner left back contact of relay I09, conductor 22 over the line loop and back over conductor 2 I, through the inner right back contacts of relays I09 and I03 to ground at the outer left front contact of relay I06. Relay I22 is now held operated through the left front contact of relay I23 and relay I22 maintains the energization of relay I06. The aforementioned release of relay I09 also closes an energizing circuit for thermostatic relay II5; this circuit is traced from the winding of relay II5 through the outer right back contact of relay I 09 to ground at the outer right front contact of relay I63. If the subscriber unduly delays hanging up the receiver, relay II5 operates, thereby connecting ground to operate the alarm II6. When the subscriber hangs up the receiver relay I23 releases causing the release of relays I22 and I06. Relay I44 is holding to ground at the back contact of relay I60 as hereinbefore described so that the release of relay I06 closes a circuit for operating the coinreturn magnet I I at station SI; this circuit is traced from battery through the left back contact of relay I2I winding of relay I60, inner right front contact of relay I63, outer left back contact of relay I06, inner right back contact of 7 relay I03, inner right back contact of relay I09, conductor 2|, right Winding of induction coil I8, upper normally closed contacts of the receiverhook switch, through rectifier I2 and winding of the coin-return magnet II to ground at coin contacts I9. The operation of magnet II returns the coins to the subscriber and the operation of relay I60 causes the release of relay I44. Relay I63 is'held by the energization of its left winding to ground at the front contact of relay I60 until contacts I9 at station SI are opened due to the return of the coins. r

In case the called subscriber is busy or the call is abandoned forany reason by the calling subscriber prior to the answer of the called subscriber, the return of the deposited coins is effected in the manner described. In case the calling subscriber wishes to regain deposited coins without making a call, it is necessary to remove the receiver and then hang it up. In this way relays I23, I6I, I63 and I44 operate in the manner hereinbefore described to close the circuit for operating coin return magnet II. When the receiver is replaced, the line circuit is restored to normal.

Since calls from coin-box stations are limited to a single conversation period, for instance, three minutes, the arrangement is such as to cause the breaking down of the connection at the end of this interval. When the metering switch MS starts its second cycle of operation at the'end of three minutes, the reoperation of relay I25 upon receipt'of the first of the metering impulses initiates the breakin'g down of the connection. The operation of relay I25 closes a'circuit for operating relay IIII; this circuit is traced from battery through the winding of relay IOI, outer left front contact of relay I25, conductor IIO, outer right front contact of relay I2I, inner left back contacts of relay I24 to ground at thermostatic relay II5. Relay IOI looks through its inner right front contact independent of relay I25 and closes a circuit for operating relay I06; this circuit is from the winding of relay I06, through the outer right front contact of relay I0 I, right front contact of relay I25, conductor I I0, outer right front contact of relay I2 I, inner back contacts of relay I24 to ground at relay II5.

Relay I06 causes the release of the connection. as hereinbefore described. Whenrelay I 09 recompleted as hereinbefore described.

In case the coin-collect or coin-return circuit is open. so that relay I60 can not operate, relays I44 and I63 remain'operated; and, relay I09 having been released, the thermostatic relay II5 operates to close the alarm circuit. If the operation of the coin-collect magnet I3 or coin-return magnet II fails to dispose of the coins and open contacts I9, relays I60 and I63 in the line circuit are held operated, and the alarm circuit is closed by relay II5.

On calls incoming to line LI, relay I03 operates when the line is seized by a final selector; the circuit for operating relay I03 is traced from battery through its winding, outer right back contact of relay I63, normal terminal and'brush I54 of switch SM, over conductor 33 and through the brush of the final selector to ground. With relay I 03 operated the incoming connection is extended over conductor 3| through the right winding of relay 34 and condenser 35 in parallel, right tion S I.

back contact of relay I02, and inner right back contact of relay I09 to line conductor 2I and extended over conductor 32 through the left winding of relay 34 and condenser 36 in parallel, outer left front contact of relay I03, and inner 5 left back contact of relay I09 to line conductor 22.

If the subscriber at station SI wishes to make a toll call, the receiver is removed and the toll number dialed without depositing any coins in the coin box. The connection is extended to a 10 toll recording operator with whom the subscriber communicates and then hangs up. No operation of the switchSM results either from the initiation of the call or from its completion since metering impulses are not received by relay. I25 15 on such a connection. When a toll operator has obtained connection with the wanted party, the connection is extended to the calling line by the operator. Such a connection is represented in Fig. 1 as established through the cord C, over 20.

the toll switching trunk T, through an incoming selector ISS and final selector CS2, to the conductors ill, 32 and 33 of the line circuit of line LI. Relay I03 operates as hereinbefore described, connecting ground to conductor 46, thereby caus- 25 ing the energization of the right winding of relay 4! and left winding of relay 48. Relays 41 and 46 both operate; but relays 44, 45 and 46 remain normal since their windings are short circuited by the back contacts of relays 4|, 4-2 and 43, 30

respectively.

When the calling subscriber removes the receiver in response to the usual ringing signal, the toll operator instructs the subscriber to hang'up,

deposit the coins required for the call, and then 35.

again remove the receiver. When the coins are deposited the contacts'l5 momentarily close a signaling circuit a number of times corresponding to the value of the coins; this circuit is traced from ground through contacts I5, over line conductor 22, through the inner left back contact of relay I09, outer left front contact of relay I03,

left winding of the differentially wound relay 34, over conductor 32, through the middle brush and conductor of both final selector CS2 and incoming selector ISS, over the lower conductor of trunk T, ring conductor of jack 50 and plug 5|, lower normally closed contacts of coin collect key BI and coin-return key 63, and through the winding of supervisory relay 54 to battery. The 50 differential relay 34 of the line-circuit operates, since there is no currentthrough its right winding as long as the receiver is on the hook at sta- Relay 34 connects the left winding of the tone source 38 through condenser 37 and the 55 right front contact of relay 34 to line conductor 3| thereby transmitting a tone to the toll operator each time contacts I5 at station SI are closed by the coins which are deposited. Thesuper visory relay 54 of the toll operators cord operates each time contacts I5 close thereby extinguishing the supervisory lamp 55. Thus, the toll operator receives both audible and visual signals to indicate the Value of the coins deposited.

When the subscriber at station SI removes the receiver after depositing the coins, the toll operator completes the connection between the calling and called subscribers; if necessary the operator can re-ring the calling subscriber in the usual manner. The talking connection having T through the conductors of plug 5! and jack 50,

over the conductors of trunk, T, through the in-' coming selector ISS and final selector CS2, over conductors 3| and 32, and through condenser 40 across the windings of voice frequency relays 4|, 42 and 43 in the line circuit of the calling subscriber. The frequency of the two sources 65and 66v is such as to cause the operation of relays 4| and 42 without operating relay 43. The operation of relays 4| and 42 opens the short circuit across the windings of relays 44 and 45 so that these relays both operate. The operation of relay 44 causes the release of relay 41. Relays 41 and 48 are slow in releasing and each of relays 44 and 46 are arranged to close holding circuits for relays 48 and 41, respectively. The release of relay 41 closes a circuit from ground at the inner left front contact of relay I03, over conductor 49, through the inner right front contact of relay 45, back contact of relay 41, conductor H2, and through the windings of relays I26 and |2I in series to battery. Relays |2I and I26 are thus operated and they lock as hereinbefore described to ground at the outer left front contact of relay I26. Relays 4| and 42 release as soon as the coin-collect key 6| is restored to normal,

thereby causing the release of relays 44 and 45' and the reoperation of relay 41'. Relay I26 closes a circuit for operating relay I44; this circuit is traced from battery through the winding of relay I44, outer right front contact of relay I03, to ground at the right front contact of relay I26. The operation of relay I44 causes the operation of relay I63.

No further operations occur, until the conversation is completed at which time the operator is informed by the release of relay 54- and consequent lighting of the supervisory lamp 55 that the receiver has been hung up at station SI. The removal of theplug 5| from jack 50 causes the release and return to normal of the selectors ISS and CS2. The release of relay I03 causes the release of relays 41 and 48 and closes the circuit from the alternating current source I35 over conductor 2| to operate the coin-collect magnet I3 at station SI as hereinbefore described.

Should the occasion arise, the operator may return the deposited coins by operating the coinreturn key 62 instead of the coin-collect key; in

which case relay 64 operates to connect the alternating current sources 66 and 61 to the line,

the frequency of the current being such as to cause the operation of

relays

42 and 43 of the calling subscribers line circuit. The operation of

relays

42 and 43 causes the operation of relays 45' and 46. The operation of relay 46 causes the release of relay 48, and a circuit is thereupon closed for operating relay I02. The circuit for operating relay I02 is from battery through its winding, back contact of relay 48, outer front contact of relay 45, over conductor 49, to ground at the front contact of, relay I 03.. Relay I02 releases relays I2I and I26 if already operated since the holding circuit for these relays passes through the left back contact of relay I02. Relay |02, connects battery through its right front contact andinner right back contact of relay I09 over conductor 2| toeffect immediate operation of the coin-return magnet II. When the coinreturn key is released, the release of relay 64 disconnects alternating current sources 66 and 61 to release relays '42 and 43 and 45 and 46. The release of relay 45 causes the reoperation of relay" and the release of relay I02. The call may be abandoned or the operator may then instruct the subscriber again as to the value of the coins: which should be deposited.

If a permanent signal condition arises, no coins having been inserted, relays I23 and I6| operate in series. Relay I6I causes the operation of re- 5: lays I62 and I10 so that a line-finder operates to seize the terminal to which line LI is connected. In this case the call is automatically routed to an intercepting operator in well known manner. If a subscriber dials before the line 10 has been found by a line-finder and relay I09- operated, relay |6| releases when the first dial impulse is received, thereby operating relay I63. Relay I63 causes the release of relay I10, disconnects the calling potential from test conduc- 15 tor 26, and closes a circuit for energizing the winding of thermostatic relay 5 so that an alarm is given as soon as relay II5 operates. If the calling subscriber dials a number after dial tone is received but without depositing any coins, 20 the call is broken down as soon as metering impulses are received since none of relays I4I, I42 and I43 will have been operated. Should line conductor 22 become grounded, the operation of relay I23 alone causes the operation of relay I04 25v and relay I04 closes a circuit for energizing the winding of thermostatic relay I I5 so that the alarm circuit is closed after a predetermined interval.

What is claimed is: 30.

1. In a telephone system, subscribers lines, a subscribers coin-box station permanently connected to one of said lines, means for transmitting a signal'over said coin-box line in response to the deposit of a coin, said signal varying in char- 35. acter in accordance with the value of the coin, means responsive to said signal for registering the value of the coin, switching means for establishing a connection between the line of the coin-box station and another of said lines, means for automatically indicating the tariff for a completed call in accordance with the called number, and meansfor releasing the connection if the value of the inserted coin does not agree with the indicated tariff. 45;;

2. In a telephone system, subscribers lines, a central office common to said lines, a subscriber's coin-box station individual to one of said lines, means at said station operatively responsive to the depositing of each coin for transmitting one 50, or more signals over said line the number of signals thus transmitted being indicative of the value of the coin, means at said central oilice responsive to said signal for registering the value of said coin, switching means for establishing a 55.: connection between said coin-box line and a called line, means for automatically indicating the value of the established connection, and means for releasing the connection if the total value of all coins deposited differs from the indi- 60, cated value of'the connection.

3. In a telephone system, subscribers lines,'a subscribers coin-box station permanently connected to one of said lines, means effective upon the deposit of one or more coins for transmitting a signal over said coin-box line, said signal being indicative of the value of' the coins inserted in the coin box, means responsive to said signal for registering the value of the coins inserted, means for establishing a connection between said coin- 70; 3 box line and a called line, means for automatically indicating the tariff for a completed call in accordance with the called number, means for short-circuiting the coin-box line for a period of time suflicient for the operation of saidindicating means, and means for releasing the connection it the registered value of the inserted coins does not agree with the indicated tariff.

4. In a telephone system, a coin-box subscribers station, line and line circuit, other subscribers lines, signal means in the coin-box of said station for actuation by each coin deposited, means in said line circuit responsive to signals created by the deposit of a coin for registering the value of the coin, means including automatic switches for extending a connection from said coin-box line to a called line, means associated with one of said switches and operative in'response to the answer of the called subscriber for transmitting signaling impulses to said line circuit, the number of said impulses being indicative of the value of the completed connection, and means in said line circuit for releasing the connection if the registered value of the deposited coins is not equal to the indicated value of the connection.

i 5. In a telephone system, a coin-box subscribers station, line and line circuit, other subscribers lines, signal means in the coin-box of said station for actuation by each coin deposited, means in said line circuit responsive to signals created by the deposit of a coin for registering the value of the coin, means including automatic switches for extending a connection'from said coin-box line to a called line, means associated with one of said switches and operative in response to the answer of the called subscriber; for transmitting metering-signal impulses to said line circuit, the number of said impulses being indicative of the value of the completed connection, means for short-circuiting the coin-box line for an interval of time suificient for all metering-signal impulses to have been transmitted,

, and means for releasing-the connection if the registered value of the deposited coins is not equal to the indicated value of the connection.

6. In a telephone system, a coin-box subscribers station, line and line circuit, other subscribers lines, signal means in the coin-box of said station for actuation by each coin deposited, means in said line circuit responsive to signals created by the deposit of a coin for registering the value of the coin, means including automatic switches for extending a connection from said coin-box line to a called line, means associated with one of said switches and operative in response to the answer of the called subscriber for transmitting signalling. impulses to said line circuit, the number of said impulses being indicative of the value of the completed connection, and means for collecting the deposited coins, said means being rendered operatively efiective only if the indicated value of the connection agrees with the registered Value of the deposited coins.

7. In a telephone system, a coin-box subscribers station, line and line circuit, other subscribers lines, signal means in the coin-box of said station for actuation by each coin deposited, means in said line circuit responsive to signals created by the deposit of a coin for registering the value of the coin, means including automatic switches for extending a connection from said coin-box line to a called line, means associated with one of said switches and operative in response to the answer of the called subscriber for transmitting signaling impulses to said line circuit, the number of said impulses being indicative of the value of the completed connection, and means for returning the deposited coins, said means being rendered operatively eifective only if the indicated value of the connection differs from the registered value of the deposited coins.

8. In a telephone system, a coin-box subscribers station, line and line circuit, other subscribers lines, signal means in the coin-box of said station for actuation by each coin deposited, means in said line circuit responsive to signals created by the deposit of a coin for registering the value of the coin, means including automatic switches for extending a connection from said coin-box line to a called line, means associated with one of said switches and operative in response to the answer of the called subscriber for transmitting signaling impulses to said line circuit, the number of said impulses being indicative of the value of the completed connection, means for collecting the deposited coins, means for returning the deposited coins, means for rendering said coin-collecting means operatively effective if the indicated value of the connection equals the value of the deposited coins, and means for rendering said coin-return means operatively effective if the indicated value of the connection differs from the value of the deposited COlIlS.

9.In a telephone system, a coin-box subscribers station, line and line circuit, other subscribers lines, signal means in the coin-box of said station for actuation by each coin deposited, means in said line circuit responsive to signals created by the deposit of a coin for registering the value of the coin, means including automatic switches for extending a connection from said coin-box line to a called line, means associated with one of said switches and operative in response to the answer of the called subscriber for transmitting signaling impulses to said line circuit, the number of said impulses being indicative of the value of the completed connection, means for collecting the deposited coins, means for returning the deposited coins, means for rendering said coin-collecting means operatively effective if the indicated value of the connection equals the value of the deposited coins, and means for releasing the connection and for rendering said coin-return means operatively effective if the indicated value of the connection differs from the value of the deposited coins.

10. In a telephone system, a coin-box subscribers station, line and line circuit, other subscribers lines, signal means in the coin-box of said station for actuation by each coin deposited, means in said line circuit responsive to signals created by the deposit of a coin for registering the value of the coin, means including automatic switches for extending a connection from said coin-box line to a called line, means associated with one of said switches, and operative in response to the answer of the called subscriber for transmitting metering-signal impulses to said line circuit, the number of said impulses being indicative of the value of the completed connection, means for repeating said metering impulses upon expiration of a predetermined interval of time, means for collecting the deposited coins, said means being rendered operatively effective if the indicated value of the connection equals that of the coins deposited, and means responsive to the first of said metering impulses received by said line circuit at the end of said predetermined interval for automatically breaking down the connection.

11. In a telephone system, subscribers lines, a central ofiice common to said lines, a subscribers coin-box station individual to one of said lines, means at said station operatively responsive to the depositing of a coin for transmitting a signal over said line in accordance with the value of the coin, a line circuit at the central ofiice end of said coin-box line, means in said line circuit responsive to said coin signal for registering the value of said coin, means including automatic switches for establishing a connection between said coin-box line and a called line, means associated with one of said switches and operative in response to the answer of the called subscriber for transmitting a signal to said line circuit to indicate the value of the completed connection, means in said line circuit operative upon release of the connection for collecting the deposited coins, means in said line circuit efiective upon release of the connection for returning the deposited coins, and means for selectively rendering said coin collecting or coin returning means operatively effective dependent upon Whether the indicated value of the connection corresponds or does not correspond with the value of the deposited coin.

12. In a telephone system according to claim 1, a toll operators position, means for extending a connection from said position to said calling line, and means responsive to the coin signals over said line for transmitting tone signals to said operator and for operating visual signals to indicate to the operator the value of the inserted coins.

13. In a telephone system, a coin-box subs'cribers station and line, a toll line, a toll operators position, visual signaling means at said position, switching means comprising selector switches controlled by said operator for establishing a connection between said toll line and said coin-box line, means in the coin-box of said station for actuation by each coin deposited therein to transmit one or more signal impulses, the number of said impulses varying in accordance with the value of the coin, and circuit means individual to said line for transmitting to said toll operator a tone signal and for causing the operation of said visual signaling means in response to each of the impulses created by the deposit of a coin.

14. In a telephone system, a coin-box subscribers station, line and line circuit, a toll line, a toll operators position, switching means including an operators link circuit for establishing a connection between said coin-box line and said toll line, means in the coin-box of said station for actuation by each coin deposited to transmit one or more signal impulses, the number of said impulses corresponding to the value of the coin, supervisory means in said line circuit and supervisory means in said link circuit both responsive to said coin signal impulses, a tone generator in said line circuit controlled by the associated supervisory means for transmitting to the operator tone signals corresponding to the value of a coin deposited at said station, and visual signaling means in said link circuit controlled by the associated supervisory means for indicating the value of the deposited coin.

15. In a telephone system according to claim 1, a toll operators position, means for extending a connection from said position to said calling line, means responsive to the coin signals over said line for transmitting tone signals to said operator and for operating visual signals to indicate to the operator the value of the inserted coins, means for collecting coins deposited, means for returning coins deposited, voice frequency relays controlling said coin-collect means and said coinreturn means, alternating current generators corresponding in frequency to that required for the operation of said relays, and means controlled by the operator for connecting said generators to operate said relays and thereby collect or return the deposited coins as desired.

WILLIAM HATTON. LESLIE B. HAIGH. JEAN R. A. F. ESCANDE.