US1502168A

US1502168A - Automatic telephone system

Info

Publication number: US1502168A
Application number: US300924A
Authority: US
Inventors: Wicks John
Original assignee: Automatic Electric Co
Current assignee: Automatic Electric Co
Priority date: 1919-05-31
Filing date: 1919-05-31
Publication date: 1924-07-22
Anticipated expiration: 1941-07-22
Also published as: FR515771A; GB144252A; CH92015A

Description

July 22 1924. 1,502,168

J. WICKS AUTOMAT I C TELEPHONE SYSTEM Filed May 31 1919 5 Sheets-Sheet 1 Juhn Z/Z/ZEKE k I .k

' J. WICKS AUTOMATIC TELEPHONE SYSTEM Filed May 51 1,919 5 Sheets-Sheet 2 F ns InUEnZUF Jc/hn -Z/vJ1Uk5 m an;

July 22 1924.

. J. wlcKs AUTOMATIC TELEPHONE SYSTEM Filed y 31 1919 5 Sheets-Sheet 3 IL'LUEUZUF Jul-LIL LL71 CR5 July 22 1924. 7 1,502,168

- ,J. WICKS AUTOMATI C TELEPHONE SYSTEM Filed May 31 1919 5 Sheets-Sheet 4 Jul-m HICKS.

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July' 22 1924. 1,502,168

a J. WICKS AUTOMATIC TELEPHONE SYS TEM Fi led May 31 1919 5 Sheets-Sheet 5 am. July 22, 1924.

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nm'rao STATES PATENT orrics.

JOE'N WICKS, OF CHICAGO, ILLINOIS, ASSIGNOR TO AUTOMATIC ELECTRIC COMPANY,

' OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

AUTOMATIC TELEPHONE SYSTEM.

Application filed May 31 1919. Serial No. 800,8%.

2' '0 all whom it may concern:

Be it known that I, JOHN WIOKS, a citizen of the United States of America, and a resident of Chicago, in the county of Cook 5 and State of Illinois, have invented certain new and useful Improvements in Automatic Telephone Systems, of which the following is a specification.

My invention relates in general to an improved automatic telephone system and relates more specifically to an improved type of apparatus for use in a telephone system which is to serve as a community automatic exchange. By community automatic k5 exchange is meant that type of exchange or system which is ada ted to give service to a community in whic there may be various classes of lines each desiring to have access to all the other lines and perhaps through an operator or automatically to a second community or main exchange. The types of lines usually found in a community exchange are the single station standard telephone line, the farmer lines or rural lines, which are sometimes a relic of the manual systems and have long high resistance lines leading to the exchange with sometimes as many as ten or twelve stations for each line which must each be signaled by a code, also there may be lines of the old magneto type. I have shown in this application an 'exchange which is adapted to take care of these various classes of service by a group of standard switches, that is, the standard lines of the two wire type have direct access to the central exchange switches in the regular manner, while the other lines which are operated in any peculiar manner are provided with a .sort of translating or standardizing device which makes it possible for all lines to use the same type of central exchange switches, which switches will operate in a standard manner regardless of the type of lines used in the exchange. Among the objects of my invention are,

therefore, to provide improved repeaters.

for insertion in the substation lines to translate impulses received from telephone lines over a simplex circuit into impulses over two sides of a line in series. Also to provide a repeater of this type which is especially adapted for use in a ring back system so that a substation on a party line may call another substation on the same line and may ring back through the repeater which is so arranged that the repeating coil and the various relays are cut out to provide a straight metallic circuit for signaling. Another-"object of the invention is to provide improved switches for code ringing either to the calling or called line, for use with rural lines having a large number of stations on the line.

In the drawings I have shown two of the lines of a community automatic exchange with the repeaters associated therewith, together with the central exchanges switches necessary for calling between the various types of lines, and for calling back on a party line. In the drawings:

Fig. 1 shows a line which may have a number of stations thereon, only two of which are shown. This line terminates in a repeater B which is inserted in the line ahead of the line switch G of that line.

Fig. 2 shows a rural connector switch H having a code selector M, (Fig. 3), and a code ring back switch N (Fig. 3), associated therewith.

Fig. 4 shows another line in the system, having two stations of the magneto type,- the circuits of which are arranged for dialing over a simplex circuit. The line shown in this figure also has a repeater D and a line switch C individual thereto. The line switch 0' also has access to the connector H (Fig. 2) in common with the line switch C (Fig. 1).

Fig. 5 shows a special test selector R and a test connector P for use in testing the various lines in suchcommunity exchange which switches will be further explained hereinafter.

I will now explain my invention more in detail by referring to the drawing and describing the operation of the various switches when one subscriber calls another. Let'us assume for the purpose of this illustration that the subscriber number one on the line A (Fig. 1) desires to call the subscriber number 2 on the line E (Fig. 4). When the subscriber #1 (Fig. 1) removes his receiver to initiate a call a circuit is closed from battery through coil 5, winding 6 of the repeatin coil over the line A to and through the su station circuits at station #1, and back over the other side of the line through the winding 7 of the repeating coil and relay 10 toground. Relay 10 energizes over this circuit to close the springs 11 in the circuit of relay 12 which also energizes to open the sprin s 13 and 14 to open the circuit of specia relay 15 and the private normal conductor. Relay 10 also closes the springs 16 to complete the circuit of the line relay 17 of the line switch C, from ground through springs 18 and 19, windin 9 of the repeating coil, resistance 20, win ing 8 of the repeating coil, springs 21 and 22, and

. through relay 17 to battery. Relay 17 operates in the usual manner to close a circuit including high resistance relay 23 and rotary magnet 24 in series at springs 25, and also prepares a circuit at springs 26 for the rotary magnet 24 direct to the private wiper 27. Now, if the line switch is standing with its wipers restin on a busy trunk line, there will be a round present on the test contact thereof w ich Wlll now complete the last mentioned circuit to cause the operation of rotary ma net 24 to step the wipers of the I switch to t e next set of contacts in its bank.

This operation of magnet 24 will continue in 27 continues to find grounded contacts of busy lines. As soon as an idle trunk line is reached upon whichthere is no ground present, then relay 23 will be no longer shorted and will energize over the series circuit with magnet 24 but its high resistance will prevent the energization of magnet 24. Relay 23, upon energizing, disconnects the line relay and ground from the line circuit and closes the springs 21 and 28 and springs 19 and 29 to cut the line through to the trunk line associated with the seized set of contacts which trunk line we will assume in this case to be the trunk line leading to the connector switch H (Fig. 2). As soon as the connec tion is thus extended the circuitof line rela 30 of the connector switch H is closed, said circuit including the windings 8 and 9 of the repeating coil in the repeater B, the springs 16 controlled by the line relay 10 of repeater B, and the line wipers of the line switch C. Relay 30, upon energizing, closes a circuit at sprin s 31 and 32 to energize slow relay 33, whic inturn supplies groundthrough springs 34 to the release trunk to maintain the switch 0 in operated position, prepares a circuit for the vertical magnet 35 at springs 36 and 37 through the side switch wiper 38 in first position, and through the slow-acting series relay 39.

The calling subscriber will now 0 erate his calling device in accordance wit the first digit of the called subscribers number. Each time the calling device is operated, the circuit of the line relay 10 of the repeater B is opened a number of times. Relay 10 opens the circuit of the line relay 30 of the connector H a corresponding number of times at the springs 16, and of relay 12 at springs 11. Relay 12 being slow acting maintains its armature in attracted position. Relay 30, however, operates to complete, at springs 31 and 40, the circuit including relay 39 and magnet 35. Magnet 35 operates to step the wipers of the switch to the desired level of the bank in which level is located the called subscribers line. Relay 39 energizes in series with the vertical magnet and remains energized during. this series of impulses to hold the private magnet 41 energized over a circuit extending from ground through springs 42 and 43, and through the left hand winding of magnet 41 to battery.

Soon after the impulses for the first digit the vertical magnet 35 and prepares the circuit of the rotary magnet 44. The side switch wiper 45 prepares a circuit for the right hand winding of private magnet 41 'to the private wiper 47, and the wiper 46 prepares a circuit for the upper winding of the busy relay 48.

All the contacts similar to 49 and 5'0 in the bank of the connector H which lead to individual lines are connected together and grouped together in one or more levels of the said connector. Assume now that the first digit caused the wipers to be raised opposite a level in which the contacts 49 and 50 and other similar test contacts are located. Now, when the calling subscriber operates his dial for the next dlgit, the line relay 10 of the repeater B again controls the circuit of line relay 30. Relay 30 in this case completes a circuit, each time it deenergizes,.for the rotary magnet 44 in series with relay 39 and with springs 51 of relay 48. Each time the magnet 44 operatesit rotates the wipers one step toward the called line and also closes a circuit for the lower Winding of relay 48 at springs 52. Relay 48 therefore energizes momentarily with each impulse and opens the circuit of the rotary mosses magnet 41 energized during impulses and for a short time thereafter. As soon as the

wipers

54, 55, 56 and 47 reach the called line the impulses cease and in case the called line is busy and a roiind is'present on the test contacts 49 an 50 thereof, then one circuit will be completed for the right hand winding of private magnet 41 through zsrde switch wiper 45 and wiper 47, and another circuit will be completed for the upper winding of the busy relay 48 through side switch wiper 46 and private wiper 56. Magnet 41 will therefore be held energized to hold the side switch wipers in second position and relay 48 will operate to connect the busy tone to the calling line through springs 57, and to open the circuit of the rotary magnet 44 at springs 51.

The calling subscriber must in this case hang up his receiver and release the connection or wait until the line becomes idle. If the called line is idle however, and no ground is present on the test contact thereof, then when the wipers 56 and 47 meet said test contacts, relays 41 and 48 will be no longer energized and magnet 41 will fall back and allow the side switch to pass to third position. Side switch wiper 45, upon reaching third position connects ground direct to the wiper 47 to energize the bridge out 01f relay 60 of the called line, and short circuits the relay 61 to prevent its energization. The cut off relay 60, (lzjig. 4), upon energizing, disconnects the line relay 62 from the called line but does not cut the line through to the wipers.

The line E being a party or rural line and having a plurality of stations bridged across it, then the calling subscriber must send another digit to the connector H to operate 1ts associated code selector M to pick out the proper code to signal the desired subscriber. It. will be understood that in, a system of this sort, there are a number of'code interrupters S, S, etc., each being capable of supplying two or more codes, that 1s, 1f either of the codes 111- or the code ;11-2 are desired, then the code selector M will be operated to its third or fourth sets of contacts leading to the code interrupter S, while for the two codes 1-1-3 or 114 the code interrupter S will be selected, and so on, so that there are a number of code interrupters each supplying two codes or more if desired, and there will be as many sets of contacts in the bank of the code selector M as there are codes or parties on the largest party line. The code interrupters S, S, etc, are common to the connectors.

As the calling subscriber sends the impulses of the final digit, relay 10 of the repeater is again operated to control relay 30. Relay 30 in this instance controls a circuit which extends as follows: ground through springs 63, springs 31 and 40, springs 36 and 37, relay 39, side switch wiper 38 in third position, springs 64, conductor 65, and magnet 66 to battery. The magnet 66, (Fig. 3) is operated a number of times to step the wipers 67, 68, 69 and 70 to a set of contacts in their bank corresponding to the code desired. Assume that the digit called is 3, then the wipers step to the contacts 71, 72, 73 and 74 a'nd'conie to rest thereon. As soon as the wi cr .70 meets the grounded contact 74 and re ay 39 falls back a circuit is closed for the wiper out on relay 75 (Fig. 2) as follows: ground through contact 74 and wiper 70, conductor 76, springs 77 and 78, springs 79, and relay 75 to battery. Relay 75 operates to open the circuit of the stepping magnet 66 at springs 64, closes a holding circuit for itself at springs 80, and cuts the ringing circuit through to the line wipers 54 and 55 and therefore to the called line. lViper 69 (Fig. 3) upon reaching contact 73, closes a circuit from ground through interrupter' 81, (Fig. 2), off normal springs 82, springs 83 of ring out of? relay 84, conductor 85, wiper 69, contact 7 3', and rotary magnet 86, to battery. The intermittent operation of the magnet 86 causes the wipers 87, 88, 89 and 90 to move over the contacts in their banks in a rapid step by step manner. The energization of relay 75 of connector H closes a ringing circuit for the called line which extends from battery through the upper winding of the ring out OK relay 84, springs 91 and 92, springs 93 and 94, wiper 54, conductor 98 to Figure 4 over said conductor through a condenser 97 and special alternating current relay 96, back over conductor 95, wiper 55, springs 99 and 100, springs 101 and 102, through a pair of springs 103 and 104, which will be closed by relay 105 in a manner to be explained, conductor 106, wiper 67, contact 71, to ground through springs 108 and 109, while relay 114 is deenergized, and to the ringing generator G where said relay'energizes. The relay 105 will also be energized by a circuit from battery through said relay, springs 110, conductor 111, wiper 68, contact 72, wiper 89, and as soon as the magnet 86 steps the wiper 89 onto the first contact it will meet ground. Relay 105 will therefore energize and lock to ground through springs 112 and off normal springs 113, and will also close the springs 103 and 104 in the ringing circuit. Now, as the wiper 90 of the code interrupter steps over its associated contacts, the circuit of relay 114 will be closed on every other contact to connect the generator G to the circuit extending through springs 115 and 108, contact 71, wiper 67 conductor 106, and over the previously traced circuit to and through the alternating current relay 96 and back to battery through the winding of relay 84, and also to a branch circuit which extends, asvwill appear presently, over the lineconductor 130 to the called station, returning via line conductor 131 to ground at spring 120. The station on the called line whosecode is 1-1-1 will answer the call and upon lifting his receiver will close a circuit for relay 84 at springs 123 by energizing relay 121. Relay 84 energizes to open the. circuit of the stepping magnet 86 at springs 83, o ens the

springs

92 and 91 and 101 and 102 in the ringin circuit and locks itself ener ized. Wheat e springs 92-and 101 meet is eir front contacts, the circuit of the back bridge relay 115 is completed in series with the right handwinding of the repeating coil associated with the called line,

' and the said relay 115 will therefore energize to reverse the connections of the line relay to'the calling line. When the relay 105 connected generator current to normal conductor 95 of the called line, said alternating current first passed through the alternating I current relay 96 which is individual to the line E (Fig. 4). Relay 96 energizes with the first impulse of current to close the circuit of the slow relay 116 and maintain said relay energized during ringing. Relay 116 upon energizing, cuts out the windings of the repeating coil associated with the repeater D at springs 117 and 118 and springs 119 and 120, thereby providing a clear metallic circuit for ringing current to pass through to the called line. When the called subscriber answers the circuit of the line relay 121 of the repeater is closed at the s rings 122 of the ca led station during the rst silent interval, relay 116 having deenergized and relay 121 operates to close the springs 123 to complete the circuit of relay 84 and later of relay 115, as previously mentioned.

Conversation may now proceed in the usual manner and when completed, the calling subscriber restores his receiver to open the circuit of the relay 10 which in turn opens the circuit of therelay 30 of the connector at s rings 16. Relay 30 falls back and opens t' e clrcuit of slow relay 33 which in turn falls back to remove ground from the holding circuit of the line switch C and close the circuit of release magnet 124. Magnet 124 operates to release the connector H which operation restores the oil normal sprin s. T e closure of springs 77 .and 125. by re ay 33 completes a circuit for the rotary magnet 66 from ground through contact 74, wiper and including the interrupter sfirin s 126 of the magnet itself. Magnet 66 t ere ore operates in the mannerof an interrupter to rotate its wipers 05- the bank and in readiness for the next call. It will be understood that the wipers of the code selector M and the codeinterrupter are of the double end type so that as one end moves ofi the last contact the other end stands in readiness to step onto the first contact.

stepped to their fourth set of contacts then the code associated with the wiper 88 of the code. interrupter will be selected, this code being1-1-2 rings. Furthermore, if other codes are desired then the code selector will he stepped to'a contact leading to another code interrupter which has two other codes associated with it. More than two codes may be associated with each code interrupter if desired by providing more sets of contacts in its bank and more wipers and relays.

It will be understood that the connector switch H must be able to make connection with party lines as described, with single station lines, and must also have access through some one of its levels to trunk lines leading to another or main exchange in order to meet the requirements of community exchange systems.

1 will next describe the method by which any of the subscribers on the line E (Fig. 4) rzihay size and operate the connector H It will be noticed that the substations of the line E are of a different ty e than the 'stations'on the line A, Fig. 1. he substation 1, for instance, is of the magneto type of substation havin a ringer 127 bridged across the line circuit and a hand enerator 128 of well known type also in bri ge of the line. In a line of this type the wires leading to the central station are usually of such high resistance as to render two wire dialing such as is used by the stations on line A (Fig; 1) impractical, and the dialing circuit for station 1 extends from ground through the calling device springs 129, springs 122, windings of the two coils of the ringer in parallel,

line wires

130 and 131 in parallel,

windings

132 and 133 of repeating coil in parallel, and through relay 121 of the repeater D to battery. This relay 121 corresponds in action to the line relay 10 of the repeater B (Fig. 1) and operates in a similar manner to energize relay 134 to remove the windings of relay 96 from across the line and closes the circuit of the line relay 62 of the line switch C atsprings 123. Thus the line relay 121 is controlled over a simplex circuit by the operation of the calling device springs 129, and the said relay 121 controls first the line switch 0' and then the,

0 of a two wire type of station. It. will aecaaee also be understood that the repeaters B and D are for improvin the calling impulses from a line such as or E which is of too hi h resistance to properly operate the line re ay of the connector H direct and are also in some instances such as in the case of the repeater D, for translating impulses over a simplex circuit into impulses over two sides of a line in series. Should the line E be changed over to two wire substations, then it will be seen that the repeater D need only be changed by connecting the coil 135 to the terminal 136, by inserting a condenser between the

windings

132 and 133 of the repeating coil, and by connecting the upper terminal of relay 121 to ound instead of battery. Also if the line should be shortened so that it would be of a lower resistance, then the repeater B could be disconnected at the dotted jumpers shown and the line A-connected direct to the line switch 0.

I will now describe the operation of the switch H and its associated apparatus when a subscriber (for instance the subscriber #1 on line A) starts a call to the subscriber #2 on his own line. In this case the call is extended to the connector H in the same manner as before described. In this case, however, assuming that the ring back switches such as N accessible to the connector are located in the second level of the connector H, the'subscriber calling will therefore operate his calling device for the digit 2 to step the wipers 54, 56, 47 and to the second level of the bank in the same manner before dpointed out by means of line relay 30 an vertical magnet 35, thereby causing the private magnet 41 to step the side switch wipers to second position, and causing the off normal springs 137 to be closed. As soon as the side switch wipers reach second position a digit will be sent such as one if the whole level consists of ring backs or 2 if the first ring back in the level is on the second contact. In any case the relay 30 is again operated to control the rotary magnet 44 to step the wipers to the first set of contacts leading to a ring back switch N (Fig. 3). When the wipers.54, 56, 47 and 55 meet the contacts 130 to 133, inclusive, of the ring back, the wiper 56 meets battery through the resistance 134 which short circuits-the .up-

per winding of relay 48. If the first switch N is busy, then ground through springs 135 will be present on contact 132 and will energize the right hand winding of private magnet 41 to hold the side switch in second position. Now. as soon as the relay 39 falls back, another circuit will be closed for the rotary magnet 44 from ground through springs 42 and 136, springs 137, wiper 38, springs 51, and magnet 44 to battery; Each time magnet 44 operates it energizes relay 48 which in turn opens the circuit of magallow the side switch to pass to third position. As soon as the wiper 46 reaches third position the circuit of switching relay 6'1 is closed from ground through said relay, springs 137, wiper 46, wiper 56, contact 131, and resistance 134 to battery. Relay 61 energizes over this circuit to disconnect the line relay 30 and all other relays from the trunk circuit and to connect the trunk circuit through the

springs

138 and 139 and springs 140 and 141, and through back contacts of springs of relay direct to the wipers. Relay 61 also opens the s rings 63 to prevent the release of switch when the line relay falls back and locks itself energized from ground which is supplied from relay 143 of switch N. As soon as this circuit is closed a circuit is completed for the line relay 142 of the ring back N- in series with the extended line circuit and with the springs 16 of the line relay 10 of the repeater of line A. Relay 142 energizes to close a circuit for slow relay 143 which in turn energizes to supply a" holding ground to relay 61 of the connector H and prepares a circuit for the relay 144 and the rotary magnet 145 of the code selector.

The calling subscriber now operates his calling device to select the proper code to signal the called party. Relay 142 in operating closes a circuit a number of times extending from ground through springs 146 and 147, springs 148 and 149, springs 150,

' set of contacts leading to the code desired,

which may be on any of the interrupters S, S, etc. Assume the code in this case to be 1.1-3, then the wipers of the code selector move to their fifth set of contacts, thereby picking out the lower pair of wipers on the code interrupter. Now, a circuit is closed from interrupter 152, springs of relay 143, wiper 154, contact 156, and magnet 157 to battery. Magnet 157 therefore operates to step the wipers of the code interru ter S over its contacts. Also as soon as re ay 144 falls back a circuit is closed from ground through contact 158. and wiper 155 through springs 159 and relay 151 to battery. Relay 151 energizes to open the springs 148 and 149 and to close the

springs

148 and 160 to prepare a new holdin circuit for the relay 143 to be completed ater. Nothing is. done by this switch N until the calling subscriber restores his receiver to the hook as is common practice in ring calls. When this is one the circuit of the backline relay 10 is opened by the switch hook springs and relay 10 deenergizes to open the circuit of the line relay 142 of. ring back N. The switches N, H and O are not restored at this time as relay 143 stays energized and holds ground on the release trunk. The line relay 142 on falling back closes a circuit from ground through springs 146 and 147,

springs

148 and 160, springs 161, and relay 143 to battery. Relay 142, a socloses, springs 162 which complete a circuit from battery through relay 163, springs 164 and 165, springs 162, springs 166, wiper 153, contact 167, wiper 168 of the codemterrupter, and through the first contact of its bank to ground. Should the subscriber delay in hanging up his receiver, then this circuit would not be ,closed until the code .interrupter again reached the first or last contacts of its bank to prevent the starting of the ringing in the middle of the code. Relay 163 energizes over this circuit, and locks itself energized through

springs

160 and 148, and springs 146 and 147. Relay 163 also disconnects the line relay 142 from the extended trunk circuit and closes a ringing circuit which extends as follows: from battery through relay 169, springs 170 and 171, contact 133 and wiper 55 of the switch H, springs 99 and 172, sprin 141 and 140, line wiper of line switch and its contact, springs 29 and 19, condenser 173, relay 15, springs 13, springs 21 and 28, upper wiper of switch C, springs 138 and 139, springs 174 and 94, wiper 54 and contact 130, conductor 175, springs 176 and 177, wiper 152 of the code selector, contact 178, sprlng 179, alternately to ground through the back contact of said spring and to generator Gr". Relay 180 is intermittently energized in accordance with the code 113 as the wiper 181 passes over its bank contacts to signal the called party. Relay 15 of the calling line operates to close the circuit of relay 182 which gives a clear circuit to the ringing current excluding the repeating coil. Now, when the called party answers by removing his receiver a circuit is closed for the relay 169 for direct current, and this relay energizes over the previously traced circuit to open the springs 161 in the holding circuit of relay 143. Relay 143 deenergizes to open the circuit of magnet 157 and interrupter 152, and closes the springs 183 which completes a circuit for magnet 145 through springs 184 and wiper 155 of the code selector to ground. The relay 15 of the repeater of the calling line opens the circuit of relay 182 as soon as ringing current is out oii and restores the line relay 10 to its connection with the calling line after a short interval. The magnet 145 operates as an interrupter to rotate the wipers 152-155 inclusive, back to normal position when the circuit of said magnet is opened by wiper 155*. Relay 143 also opens the sprin 150 I in the circuit of relay 144 which was a eady open at springs 148 and 149. As soon as the wipers of the code selector come to normal the circuit of the relay 151 is opened by wiper 155 and'said relay falls back to remove the holding ground from relay 163 which in turn falls back to restore the line tion to the ring back switch N. If, however, the line relay 10 has energized rior to the deenergization of relay 143 an has closed the springs 16, then the switch C may not release but the switch H will release over a circuit from ground through springs 63, springs 31 and 40, springs 36 and its back contact, and off normal springs through the release magnet 124 to battery. In either case the switch C will take the trunk to the switch H again due to the closure of springs 16 which will again operate said switch. The calling and called subscribers find talking battery through the windings of relays 10 and 5 and may converse. When conversation is terminated the restoration of the re ceivers of the calling and called lines causes the release of the switch C.

It will thus be seen that a subscriber may call the ring back number in the connector, then pick out a code on one of the code interr'upters S, S, etc., and may then release the connection to the ring back by the response of the called subscriber and converse over the line direct. The connector switch H (Fig. 2) also has access through certain levels to trunk lines leading to another or main exchange. One of these trunk lines would lead from contacts such as 193, 194, 195 and 196 in the banks of the connector. The contact 194is shown connected to bat tery through a resistance and the operation of the switch H in calling such a trunk line to the other exchange would be the same as when calling a ring back switch with automatic rotation in search of an idle trunk and relay 61 would energize to switch the circuit through clear metallic through the switch H.

In Fig. 5 I have shown a test selector and a connector. The test selector R is of a standard type of selector except that it is shown accessible through a jack J. This selector may be used by an attendant in the exchange or by an operator at the main exchange to callthrough connectors such as H to a test connector such as P (Fig. 5). This test connector has a special set of banks leading to the various lines in the exchange. I have shown in Figs. 1 and 4 two sets of the contacts of such banks, one for the line to battery.

A and another for the line'E. It will be seen that when testing any of the lines for trouble, etc., the operator or attendantwill desire to have direct access to that line without having to go through the repeating coil of the individual repeater thereof. The multiples of the lines in the test connector therefore are taken from a point between the substations and said repeater, and means is provided for disconnecting the repeater. over the private normal. I will explain the operation of the test connector only in general. When connection is made with this test connector by a connector such as H, through a set of contacts similar to the contacts 193-196 inclusive, in which the contact corresponding to contact 194 leads to battery, relay 61 of the connector will therefore energize to switch through and line relay 200 of connector P will energize in series with the calling device at the op erators position. Line relay 200 is energized to energize relay 201 to prepare the circuit of relay 202 and vertical magnet. 203. When the digits are called relay 200 operates first to control the vertical magnet 203 and then when relay 202 falls backin the pause between digits, the operating circuit is shifted to the rotary magnet 204. When the last digit is called. the relay 205 and rotary magnet 204 are operated to step the wipers" to the called line, after which relay 205 deenergizes to close springs 206. Relay 201, upon energizing, placed ground on the release trunk to hold relay61 of the connector H energized. If the called line is busy then relay 211 will not energize because the private normal conductor is open at springs 14 of relay 12. The operator if desired may converse with the busy called subscriber through the

condensers

212 and 213 and the back contacts of the springs of relay 205. The operator may then release if desired by opening the line and deenergizing relay 200 which closes a circuit for release magnet 214 through springs 215 and 216, springs 217 and 218, springs 219. 011 normal springs 220, and magnet 214 to battery. If, however. the called line be idle then the relay 211 will energize from ground through springs 207 of relay 201, lower winding of relay 211. wiper'209. and bridge cut off relay 227 of the called line Relay 227 of the called line opens the line circuit to the repeating coil and to the line relay of the line A. vRelay 211 on energizing opens the circuit of mag net 204, opens the springs 219 in the circuit of the release magnet. locks itself to ground through its upper winding, through springs 221 and 222. springs 223. and springs 224 to ground. Relay 211 also short circuits the

condensers

212 and 213 in the talking circuits by the resistances 225 and 226, and removes the line relay 200 from the talking circuit. Relay 200 falls back and opens the circuit of relay 201, relay 201 falls back, opens the springs 207, but does not close the circuit of the release magnet 214, which is held open at springs 219. The ground through ofi normal springs 224 and springs 223 and 222 holds the switches H, etc., up over the release trunk. It will be seen now that the operator may perform any of the necessary tests desired over a clear metallic circuit.

"After all tests are completed the operator is provided with a special: relay 230 for releasing the extended connection as it will be seen that merely opening the line will not release the switches. When the operator desires to release she throws her ringing key to energize the tuned ,relay 230. Relay 230 energizes and closes the springs 231 which complete a circuit from ground through springs 215 and 216, springs 21'? and 218, springs 231', springs 220, and magnet 214 to battery. Magnet 214 releases the switch P and thereby restores the 011 normal springs, the springs 224 removing ground from the release trunk to release the switches ahead.

It will be seen from the foregoing that I have provided a very flexible system of a community exchange and one which is especially adaptable to a small rural community exchange in which there may be almost any number of difierent classes of lines and trunks in which the same set of main exchange switches are used in all calls.

Having fully described and ascertained the features and objects of my invention, what I consider to be new and desire to have protected by Letters Patent will be pointed out in the appended claims.

What I claim as my invention is: y

1. In a telephone system, a subscribers line, a repeater for said line, means for connecting with said line and for projecting ringing current thereover, and means responsive to said ringing current for disconnecting said repeater from the line.

2. In a telephone system, a line, a telephone on said line, an automatic switch individual to said line, a repeater between said telephone and said switch in the line, a called branch for said line, means for extending a connection to the line via said called branch, and for projecting signaling current thereover, and means responsive to said ringing current for'eliminating said repeater from the line.

3. In a telephone system, a line, a plurality of stations on said line, an automatic switch accessible to said line, a ring back switch accessible to said automatic switch, said ring back switch having a code selector individual thereto, a plurality of code interrupter switches accessible to said code selector and to said connectorin common, and means for operating the code selector of the established ring back to pick out a code interrupter switch and a particular code on that swltch line connecting the telephone with a central oifice, a connector switch associated with said line, said connector switch having a progressively movable wiper, means for controlling said connector to cause said wiper to establish connection with said line, and for transmitting current through said connector and over said wiper to the said line for signaling the telephone, said. means also for controlling said connector to cause said wiper to establish connection with another line, a source of ringing current associated with said other line, and means for transmitting current from said source over said other line and over'said wiper and through said connector to the said first mentioned telephone line for operating the signal at the telephone.

5. In a telephone system, an automatic switch having means for progressively moving a wiper, a source of rmging current and a signal associated with said switch, and means for building up a connection in one direction from said signal to said generator through said wiper for operating said signal, and also for building up a connection 1n the other direction from said generator to said signal through said wiper for operating said signal, said means comprising circuit arrangements for operating said switch to select and connect with said generator in the first case, and circuit arrangements for operating said switch to select and connect with said signal in the second case.

6. In a telephone system, an automatic switch having means for progressively mov ing a wiper, a source of ringing current and a signal associated with said switch, and means for building up a connection from said signal to said generator through said wiper for operating said signal, and also for building up, a connection from said generator to said si a1 through said wiper for operating said signal, the signalling circuit in the first case extending through the said signal, said wiper, a contact engaged by said wiper, and said generator in the order named, and in the second case extending through said generator, said wiper, another contact engaged by said wiper, and the said signal in the order named.

7. In a telephone system, an automatic switch having means for progressively moving a wiper, a source of ringing current and a signal associated with said switch, and means for building up a connection in one direction from said signal to said generator through said wiper for operating said signal, and also for building up a connection in impu se sendin device for controlling said automatic switc over said llne for selecting said generator to establish said first connec tion between the signal and the generator, another telephone, a line for, said other telephone, an impulse sending device associated with said second telephone for sending impulses over said other line for operating said automatic switch to select said signal for establishing the second connection between said generator and said signal.

8. In a telephone system, a signal, a generator, an automatic progressively movable switch'for connecting said signal and said generator at one time by building up a connection from the signal to the generator and at another time for building up a con nection from the generator to the signal forestablishing a circuit between the generator and the signal for operating the signal, a relay for controlling the first circuit, a relay for controlling the second circuit, and an automatic switch for controlling said relays to cause them to automatically control the signal in accordance with predetermined codes.

9. In a tele-phone system, subscribers lines, a connector switch having access 'to said subscribers lines, a ring back, said connector switch also having access to said ring back, means whereby the connector may signal any one of said lines when the connector establishes a connection therewith, and means whereby said ring back may signal any one of said lines when the connector establishes a connection with the ring back.

10. In a telephone system, subscribers lines, a connector switch having access to said subscribers lines, a ring back, said connector switch also having access to said ring back, means whereby said connector may signal any one of said lines when the connector establishes a connection therewith, and means whereby said ring back may signal any one of said lines when the connector establishes a connection with the ring back, and automatic means for causing said signals to assume code form, said last mentioned automatic means common to both the signaling means of the connectors and in nal any one of said lineswhen theconnector establishes a connection with the ring back, said lastmentioned automatib means comprising a lurality of'code interrupters, each code in each interrupter diflering from every other code produced by any of the inte-rrupters.

12. The combination of a ring back in a telephone system and an instantaneous ring out off connector for extending connection to said ring back, and means associated with said ring back for transmitting signalling current from the ring back back through the connector to the callingline from which the connector has been operated to extend connection to the ring back, said connector including means for automatically signalling a called subscribers line independent of said ring back.

13. In an automatic telephone system the combination of a plurality of ring backs and a rotary connector for establishing connection with any one of said ring backs, a calling subscribers line, means for operating said connector from said subscribers line automatically, means for transmitting ringing current from the ring back through the rotary connector to the calling line for operating a signal in the calling line, after t connection has been made with the ring back, subscribers line, another means for operating said connector to establish connection with the said other subscribers line as a called line, and means associated with the connector for" operating the signal on the called subscribers line.

14. In an automatic telephone system the I combination of a plurality of ring backs and a rotary connector for establishing connection with any one of said ring backs, a callin subscribers line, means for operating sald connector from said subscribers line automatically, means for transmitting ringing current from the ring back through the rotary connector to the calling line for operating a signal in the calling line, after the connection has been made with the ring back, another subscribers'line, means for operating said connector to establish connection with the said other subscribers line as a called line, means associated with the connector for operating the signal on the called subscribers line, and means associated with said connector for causing said signal to be operated in accordance with a predetermined code.

15. In a telephone system, lines, a plurality of stations for each line, automatic switches accessible to said lines, relays associated with said switches for projecting ringing current to any of said lines, a plurality of code interrupters common to said switches, and means for connecting any of said relays to any of said second code interrupters to signal a desired station on any of said lines, said switches controlled in one case from one line to signal a station on another l ne, and in another case from one l ne to signal another station on the same line. 16. In a party line telephone system, connector switches, ring back switches, ringing relays for said switches, auxiliary selecting switches for said connectors and ring backs, a plurality of progressively movable switches common to said auxiliary switches, said propressively movable switches operating automatically when seized to send a code of impulses, and means for operating any auxiliary switch to pick out a particular code on one of said progressively movable switches and for then causing a ringing relay to be operated in accordance with the code selected to signal a desired subscriber.

17. In a telephone system, a line, a plurality of stations on said line, each provided with a signal, a ring back, a source of signalling current associated with said ring back, a plurality of circuit interrupters each adapted to close a circuit in accordance with a code, and means for operating said ring back to select a code and cause the signalling current to be applied to the'calling line in accordance therewith.

18. In a telephone system, a calling line, an automatic connector switch for extending connections from said line to called lines,

a generator, a relay for applying said generator to the called line to signal a station thereon when the called line is other than 109 the calling line, other ringing relays accessible to said connector, and means for selecting an idle one of said other relays when the called line is also the calling line and for causing said selected relay to be operated to connect said generator to the called line to signal a statlon thereon, and a series of switches for operating any of said ringing reliiys in accordance with a predetermined co e.

19. In a telephone system, a line, a telephone on said line, an automatic switch individual to said line, a repeater between said telephone and said switch in the line, a called branch for said line, means for extending a 115 connection to the linevia said called branch, and for projecting signalling current thereover, and means responsive to said ringing 'current for eliminating said repeater from current for removing said repeater from the path of the rin ing current.

21. In a tele one system, a line extending from a subscri ers station to the exchange, means for establishing connection with said line and for connecting ringing current thereto,'and means associated withthe line at the exchange and responsive to said ringing current, for reducing the impedance of the said line to ringing current.

22. In a telephone system, a subscribers line, an automatic switch controllable in accordance with the first digit in 9. called number for extending said line in the direction of a called line, an automatic trunking switch for connecting said line with said first switch, a repeater inserted in the said line between the substation andsaid trunking switch, a circuit including a wiper of said trunking switch for controlling said first switch, a relay in said repeater for transmitting impulses over said circuit, and a second circuit including the two sides of said subscribers line in parallel over which said relay is controlled from the substation on said line.

23. In a telephone system, a subscribers l1ne, an automatic switch controllable in accordance with the first digit in a called number for extending said line in the direction of a called line, an automatic trunking switch for connecting said line with said first switch, a repeater inserted in the said line between the substation and said trunking switch, the said trunking switch being individual to said line, and the said repeater including a voice current repeating coil, a circuit including a wiper of said trunking switch for controlling said first switch, a

relay in said repeater for transmitting impulses over said circuit, and a second circuit including the two sides of said subscribers line in parallel over which said relay is controlled from the substation on said 24. In a telephone system, a subscribers line extending to an exchange and terminating in an automatic trunking switch, an impulse repeater inserted in said line, a connector switch for use in regular exchange calls, a test connector, normal conductors extending from a point between the said repeater and the substation on said line to the banks of said test connector, and other normal conductors extending from a point between the said repeater and said trunking switch to the banks of said regular connector. I

25. In a telephone system, a subscribers line extending to an exchange and there terminating in individual line equipment responsive to calls, a .voice current repeating coil inserted in said line, means for completing two diiferent classes of connections to said line, and circuit arrangements such that the said repeatin coil is included in the. talking circuit on y when connections of a particluar class are established.

26. In a telephone system, a subscribers line, an automatic connector switch for extending a connection to said line, a normally open connection in one of the talking conductors of said line, means individual to said line providing for the passage of signalling current past said open connection, and

means responsive when the receiver is removed for closing said connection to complete the talking circuit.

27. In a code ringing party line system, a party line, a connector switch operable to set up a connection with said line, a code ringing machine, auxiliary code selecting mechanism for selecting a code to be transmitted by said machine to signal the desired party on said line, a wipe switching relay in said connector for preparing the signal-' ling circuit, a circuit for said relay closed responsive to the operation of said code selecting mechanism, a pick up relay maintained energized throughout the signaling operation for completing the signalling circuit, and a circuit for said last relay completed at the roper time to start the sigonalling operation at the beginning of the selected code.

28. In a telephone system, a party line, an automatic connector switch for completing a connection to said line, a plurality of "code signalling machines, each adapted to signal a difierent plurality of the parties on said line, an auxiliary switch associated with said connector operable to select the particular code machine which is adapted to signal the plurality of parties including the desired party, and also to select the code corresponding to such desired party, and means for then transmitting ringing current over said party line in accordance with the selected code.

29. In a telephone system, a plurality of code signalling machines, each adapted to signal a line according to a plurality of different codes, a ring-back switch, a party line, a plurality of automatic switches controlled by a calling party on said line for extending connection to said ring-back switch, means for directively operating the ring-back switch to select one of said signalling machines and also to select one of the codes assigned to the selected signalling machine, and means for then transmitting ringing current back over the calling line in accordance with the selected code to signal another party on said line.

30. In a telephone system, a plurality of code signaling machines, each adapted to signal a line according to a pluralty of diiferent codes, aJring-back switch, a party line, a pluralty of automatic switches controlled by a calling party on said line for extending connection to said ring-back switch, means for directively operating the ring-back switch to select one of said signalling machines and also to select one of the codes assigned to the selected signalling machine, a ringing generator, and means for then transmitting ringing current from said generator back through a wiper of said ring-back switch and over the calling line to signal another party on said line.

31. In a telephone system, a party line, a plurality of code signalling machines, each adapted to signal a different lurality of the parties on said line, a ringack switch, a plurality of automatic switches controlled y a calling party on said line for extending connection to said 4 ring-back switch, means for operatin the ring-back switch to select the particu ar signalling machine which is adapted to signal the plurality of parties including the desired called party, and also to select the ringing code corresponding to such desired party, and means for then transmitting ringing current back over the calling line in accordance with the selected code.

32. In a code ringing telephone system, a code ringing switch having a plurality of wiper sets, bank contacts for said sets wired for a plurality of codes, another code ringing switch having a plurality of wiper sets and bank contacts wired for a different plurality of codes, and a code selecting switch having access to all the wiper sets of both ringing switches.

33. In a code ringing telephone system, a code ringing switch having a plurality of wiper sets, bank contacts for said sets wired for a plurality of codes, another code ringing switch having a pluralit of wiper sets and bank contacts wired" or a different plurality of codes, a code selecting switch, wipers for said selecting switch, and a set of bank contacts accessible to said selecting switch wipers individual to each wiper set of both ringing switches.

34. In a code ringing telephone system, a ,code ringing switch having a plurality of wiper sets, bank contacts for said sets wired for a plurality of codes, another code ringing switch having a plurality of wiper sets and bank contacts wired for a difierent plurality 0t codes, a connector switch for connecting with a party line, and a code selecting switch associated with said con nector having access to all the wiper sets of both ringing switches.

85. In a code ringing telephone system, a code ringing switch having a plurality of wiper sets, bank contacts for said sets wired for a plurality of codes, another code ringing switch having a plurality of wiper sets and bank contacts wired'for a difierent plurality of codes, a ring-back apparatus for handling revertive calls on party lines,

and a code selecting switch associated with said ring-back apparatus having access'to all the wiper sets of both ringing switches.

36. In a code ringing telephone system, a set of code ringing relays, a switching device for energizing said relays at intervals to cause each relay to transmit a different ringing code, a second set of code ringing relays, a second switching device for intermittently energizing the relays of the second set to transmit a difierent lurality of ringing codes, a connector switch for connecting with a party line, and a code selecting switch associated with said connector and having access to all the relays of both sets.

37. In a code ringing telephone system, a set of code ringing relays, a switching device for energizing said relays at intervals to cause each relay to transmit .a different ringing code, a second set of code ringing relays, a second switching device for intermittently energizing the relays of the second set to transmit a diflerent plurality of ringing codes, a ring-back apparatus for handling revertive'calls on party lines, and a code selecting switch associated with said ring-back apparatus and having access to all the relays of both sets.

38. In a code ringing telephone system, a set of code ringing relays, a switching device for energizing said relays at intervals to cause each relay to transmit a different ringing code, a second set of code ringing relays, a second switching device for intermittently energizing the relays of the second set to transmit a different plurality of ringing codes, a code selecting switch common to both sets of relays, and ringing circuit connections connecting the bank of said selecting switch with all the relays of both sets.

39. In atelephone system, a party line, a ring-back switch, means including a repeater and a plurality of automatic switches controlled by a calling party on said line for extending a connection to said ring-back switch, inductive connections in the line circuit at said repeater, an alternating current relay bridged across the line between the repeater and the first of said switches, and means controlled by said relay for com leting a metallic ringing circuit past sai inductive connections when ringing current is transmitted back over the line from said ring-back switch.

40. In a telephone system, a repeater, a line switch, a subscribers line extending through said repeater to said line switch, means in the repeater controlled over said line when calling for operating said switch to extend the line toward a called line, a connector for extending a connection to said subscribers line, normal conductors connected to said line between the repeater and mal conductors from said connector.

41. In a telephone system, a repeater, a line switch, a subscribers line extending through said repeater to said line switch, a line relay. in said repeater controlled over the line, a line relay in said switch controlled from said repeater by said first relay, means for connecting with the line at two points, ahead of the repeater or between the repeater and switch, a cut off relay for disconnecting the repeater line relay when the line is connected with at the first point, and a second cut ofi relay for disconnecting the switch linerelay while leaving the repeater line relay connected when the line is connected with at the second point.

I 42. In a telephone system, a repeater, an automatic switch, a subscribers line extending through said repeater to said switch, inductive connections at said repeater dividing the talking circuit into two sections, a line relay in said repeater controlled from the substation on said line over the two conductors of the first section of the talking circuit in parallel, and a line relay in said switch controlled by said first line relay over the two conductors of the second section in series.

43. In a telephone system, a repeater, an automatic switch, a subscribers line extending through said repeater to said switch, inductive connections at said repeater dividing the talking circuit into two sections, a line relay in said repeater controlled from the substation on said line over the two conductors of the first section of the talking the talking circuit into two sections, a line relay in said repeater controlled from the substation on said line over the two conductors of the first section of the talking circuit in parallel, said line relay being energized both when the line is calling or is being called, a line relay in said switch controlled by said first line relay over the two conductors of the second section in series when the peater energized from the station on said line over the two conductors of the first section in parallel to close said normall open contact, and a line relay in said switc energized over the two conductors of the second section in series when said normally open contact is closed.

46, In a telephone system, a repeater, an automatic switch, a subscribers line ex tending through said repeater to said switch, inductive connections at said repeater dividing the talking circuit into two sections, a line relay in said repeater, a ringer and a calling device at the station on said line, a circuit for said line relay including the two conductors of the first of said sections in parallel, the two coils of said ringer inparallel, and said calling device, a line relay in said switch, and a circuit for said switch line relay including contacts on the repeater line relay and the two conductors of the said second of said sections in series.

47. In a telephone system, an automatic connector switch, a subscribers line, a branch of said line terminating in the bank of said connector, said branch comprising two sections inductively connected by means of a repeating coil, means for operating said connector to connect with said line by way of said branch, means'in said connector for connecting a source of ringing current to said branch, and a relay individual to said line for joining said sections over a path excluding said repeating coil to permit ringing current from said source to reach the substation on said line.

48. In a telephone system, a subscribers line, means including a connector switch for extending a connection to said line, a repeating coil included in the connection between the said line and the wipers of said connector, means for applying signalling current to said line from the said connector, and means individual to said line for temporarily providing a direct path for the sigpalling current excluding said repeating co1 49. In a telephone system, a subscribers line, means including a connector switch for extending a connection to said line, a repeating coil included in the connection between the said line and the wipers of said connector, means for applying signalling current to said line from the said connector, and a relay individual to said line neoaiee for closing a shunt circuit around said repeating coil to provide a direci; path for the signalling current.

50. In a telephone system, a line, a re- 5 peater individual to said line, a connector for seizing said line, means associated with said connector for applying ringing current to the line when called, a pair of relays associated with said re eater, a ring out 30 0E rela included in i e rin 'n circuit means responsive to ringing on the line for making one relay of said pair operative to disconnect said repeating coil and to complete the ringing circuit, and the other relay operative on the response of the called subscriber to complete an -operating circuit for said out off relay.

Signed by me at Chicago, Cook County, Ellinois, this 22d day of May, 1919.

JOHN WICKS.