US1542383A - Automatic telephone system - Google Patents

Description

June 16, 1925. 1,542,383

A. E. HAGUE AUTOMATI C TELEPHONE SYSTEM Filed April 16 1923 u 2 Sheds-Sheet 1 x Q In l June 16, 1925.

A. E. HAGUE AUTOMATIC TELEPHONE SYSTEM Filed April 16, 1923 2 Sheets-Sheet 2 /7 wen far A/f /"ec/ 1f Hague b WM Af/j/ 'New June 16,1925.

UNITED sures 1,542,383 PATENT" ornca sum a mason, or saocxmm, mrw YORK, assmnoa 'ro was'rnnn anaemic oonm, incoarona'rnn, or new You, R. Y., a coaroas'rron or raw roan.

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Application fled April 18, 1888. Serial Io. 632,811.

To all whom it may concern:

Be it knownthat I, Anrunn E. HAGUE, a citizen of the United. States, residing at Brookl in the county of Kings, fitate of ork, have invented certain new and v useful Improvements in Automatic Telephone Systems, of which the following is a full, clear, concise and exact description.

This invention relates to automatic telephone systems, and more particularl to systems emplckying progressively mova le automatic line nder switches for extendin sub: scribers lines to idle trunks upon the initiation of calls,

Its ob'ect is to provide an improved line finder o the multiple brush type; that is, of the type wherein a plurality 0 rows of subscribers line term nals are tested simultaneous] bya corresponding number of brush sets, t e first brus set to reach a calling line being then connected to the trunk in which .the finder terminates.

The principal feature of this invention relates to the provision of a positive arrangement for stoppin the finder brushes on the calling line trmlnals.

In accordance. with this invention the lines aretested in airs by the finder, and the test multiple 0 one of the pair of noncalling lines is so connected as to complete a circuit including a steppin the test brush engages it whic operates to connect the stepping magnet to the test terminal of the other non-calling line, from which it receives an impulse to advance the finder to the next pair of lines. If either of these lines is calling, the electrical condition of its test terminal is such that no operative circuit is closed for the said relay or the said magnet, as the case may be, and consequently the finder The 0 eration or non-operation of the brush shifting relay is now determined by which set of brushes is engaging the calling line test terminal.

If it is the set to which the brush is normally connected, the circuit arrangementis such that the brush shifting relay circuit is not closed and the normal contacts of this relay extend the callin line to the trunk. If, on the other hand, t e brush set engaging the calling line is the one to which therelay when e test terminal causes an ef- Fig. 2 shows a'selector, a connector and the called line. Y o

The line finder isof the Strowger ste banks by-step type and is equipped with two and two sets of brushes, one hundred lines terminating in each bank. The lines are in ten groups, correspon'ding to the ten verti cal positions of t e switch. Each group thereforecontains twenty lines, ten in the upper and ten in the lower bank. Every rotary position of the switch therefore embraces two lines of a grou one in the upper bank and one in the ower, and the connection is established with but one of the two; i. e., that one which is calling.

The invention will be most readily understood from a detailed description of the operation.

The initiation of a call in line X or Y operates the corresponding line relay LR, L 'R. This causes the operation of group relay G. Relay G at its armature 166 grounds the start wire 100 and at its armature 133 grounds commutator terminal 101 corresponding to the calling group. Relay N now operates as follows: ground, 166, 100, 168. 102, 103, A, battery. Relay A disconnects the brushes of the line finder from the tip and ring conductors 104. 105, to prevent interference and energizes the impulse relay A of the first selector (Fig. 2) as follows:

ground, 106, 107. 120, 108, 109, 110, 111,

105, 200, 201. A. battery. A operates slowto-release relay B which interposes a break in the line finder release circuit and prepares the circuits of the first selector to receive the setting impulses. Relay A also starts the vertical hunting movement of the finder by operating relay C as follows: battery, C. 112, 113, 114, 115. 116, 117, 118,119, 120, 107, 106, ground. Relay G closes the following circuit for the vertical r'na st 121: battery, 121, 122, 193, 124, 125, 126, 127, 108, 107, 106, ground. The vertical magnet at the end of the stroke of its armature 114 opens the circuit traced for relay C, which in releasing its armature 124. opens the circuit of the vertical magnet. This well known cycle continues until the-group brush 128 reaches the calling group commutator segment 101, and the ground on this segment -1.29, 139, 130, 131, 123, 101, 132, 133, ground.

Relay E, which is slow to release, operates in this circuit and locks as follows: battery, vertical magnet, 121, 122, 125, 150, 151, 152, right winding of relay E, 127, 108, 120, 107, 106, ground. Relay E connects the commutator ground to the rotary magnet 134 to operate the same to rotate the brushes into the bank and begin testing the lines of the calling group of twenty lines. The circuit for said magnet 134 is as follows: battery, 134, 135, 136, 137, 138, 139, 130, 131, 128, 101, 132, 133, ground. Magnet 134 at the end of its stroke opens the circuit of relay C. Upon the. first rotary movement of the switch the original energizing circuit for magnet'134 is opened through the movement of brush 128 from its group terminal so that the further energization of magnet 134 will depend on the idle or calling condition of the individual terminals S and S. The test terminals S, S of all lines are normally grounded at the right hand armatures 161, 147, etc. of their line relays. The upper and lower lines are tested simultaneously. If both are non-calling, ground on the upper test terminal S short circuits relay F at point 140 and operates relay C. The circuit for relay 0 is as follows: battery, C, 112, 113, 114, 115, 155, 140, 156, 157, 153, 159, S, 130, 161, ground. Ground on the lower test terminal S short circuits relay D at point 141, and operates the rotary magnet 134 to move the brushes ofi these two non-calling lines. This circuit is a follows: battery, 134, 135, 133, 141, 142, 143, 144, s', 145, 143, 147, ground. The rotary magnet on attracting its armature 154 locks itself to ground over 135, 136, 141, 137. 154, 118, 119, 120, 107, 106, and at the end of the stroke of its armature 113 opens the circuit of relay C, which in releasing its armature opens the circuit of magnet 134. This cycle continues as long as grounded or non-calling terminals S, S are encountered by the finder sleeve brushes 159, 144. When a calling line is reached the test circuit acts as follows: Assuming S only is ungrounded, that is to say, line X is the calling line, relay C fails to operate since no ground is present on S, and therefore no circuit is closed for the rotary magnet 134 to the ground on sleeve multiple S and consequently the finder stops. The absence of ground on sleeve S causes relay F to operate as follows: battery, C, 112, 113, 114, 115, 155, 140, 162, F, 163, 164, 165, ground. Relay C is marginal and will not operate in this circuit.

When relay F operates a test circuit is closed to the calling line to determine whether it is restricted or non-restricted. This circuit is 3. follows: 103, 174, 175, rig t winding of B, 176, 177, 172, to the tip terminal T of the calling line. If the line is non-restricted a conductor 178, as shown in connection with line X, connects the normally grounded outer right armature of out 01f relay CO to the said tip terminal. If restricted, this conductor is absent, as, for example, as shown in connection with line Y. Relay B operates in the case of line X and locks to ground at 165 by its left winding over its left contact and conductor 164. Relay Bat its inner right armature removes ground ,at the back contact of release magnet 192 from battery, A,

conductor 1.80, which ground would otherwise prevent the subscriber from securing a trunk on certain levels of the first selector, as will appear, and said armature applies said ground over 184, 185, 156, 157, 158, 159, S, 186,193, CO, battery. Relay CO atits rightarmatures disconnects the line relay LR,.which releases the group relay G and at its left armature locks itself to said ground. Relay LR is slow to release to give the relay CO time to operate and lock. Relay CO in removing ground from conduc tor 178 opens the circuit of relay A, which releases. Relay A in releasing restores the continuity of the tip and ring conductors 104, 105, and since relay D is inert, said conductors connect the tip and ring terminals T and R, and consequently the calling line X to the first selector (Fig. 2). Relay Bat armature 151 opens the locking circuit traced including the right winding of relay E, which thereupon releases.

Assuming now that line Y had called instead of'line X, terminal S instead of S would have been ungrounded. Although relay C operates in this case due to ground on S, as described, and at its armature 136, connects the rotary magnet to terminal S, this magnet does not operate since no ground. is present on terminal S. Owing to the absence of ground on S, there is no shunt about the brush shifting relay D, and it operates as follows: battery, rotary magnet 134, 135, 136, 137. 138, 139, 130, 131, 1.70, D, 171, 116, 117, 118, 119, 120, 107, 106, ground. The rotary magnet 134 will not operate in this circuit. Relay D in attracting its armature 158 opens the short circuit described about relay F, which thereupon operates as described to connect relay A to the tip conductor in series with relay B to test for ground on the tip T of the calling line Y and not finding suchground relay A releases, which in turn releases relay E. Relay D at its innermost lower armature closes a locking circuit for itself including conductor 164 and the ofi-normal switch 165. At its armatures 172, 173,- rel y D onnects the tip and ring conduct r 104,105 to the brushes T and R and thus extends t e calling linesince in suc assess:

' on terminals Y to the first selector (Fig. 2). g If both vlines X and are calling, the finder sto and preference is given to line X. a In t is case both sleeve termm'als S and S are un unded. Due to S hem un ounded, C ails to operate, as descri and F 0 rates instead just asin the ease descri where line 7X alone was-calling. The other 0 rations are the same as those described w ere line Xalone was calling.

When the callin line is restricted -no round is connects to the tip terminal as m the case of line Y. Relay B there ore fails to operate and relay A immediately releases, apilying ground as follows to ogerate cut-o relay (1 0; ground, 106 1 8 143 and its front contact, relay D being operated, 188,144, S, 145, 189, 190, CO battery. Bela C'O operates to cut off the line relay L and at its left armature locks itself to said ground.

In the case-of a restricted line m the row engaged by the upper set of brushes, the circuit for operating the cut-off relay of such line does not lead over the front contact of rela but the circuit is as follows: ground, 100, 187, 169, 156, 157, 158 and its back contact, D being inert, 159, S, to battery through the cut-off relay of that line.

In the case of a non-restricted line in the row engaged by the lower set of brushes,

the circuit for operating the cut-off 'relayof such line is as follows: ground at the back contact of release magnet 192, inner right armature and front contact of'relay B, 184, 169, 143 and its front contact, relay D being operated, 188," 144, S, to battery through the cut-oif relay of such line.

Assuming the line connected to by the finder to be line X, the impulse relay A and slow relay B of the first selector were operated when relay A was operated on the initiation of the call, as described. When rela A released, the impulse relay was hel energized over him X by the continuity contacts of relay A. Relay A now follows the dial impulses from line X, and each time it releases, ground from the uppermost armature and back contact of relay D is applied to operate the vertical magnet 202 in series with slow relay 0, which remains energized during the impulses. The

vertical magnet ste s the brushes 203, 209, 207 to the roper evel. On the first vertical step, t e off-normal switch 204 is operated and relayE is energized over the alternate contact of relay C to pre are the rotary stepping circuit in the wel known manner. After the completion of dialing, relay 0 releases but relay E" remains locked up over its left armature, to ground B, as described for'line X, case relay B is not operated,

tact of relay D. Relay C in releasing closes a circuit through the right armature and alternate contact ofrelfay- E to operate the rotary ma at, which steps the brushes 203 onto the first trunk terminals 206, 210, 208, and by unlocking relay E is itself deenergized. If this trunk is u its sleeve terminal 208 is grounded, which shunts rela D and reoperates relay E m the wel known manner. The rotary magnet is again operated and the operations just described are re eated until an idle trunk is found, which, aving an ungrounded sleeve, relay D is unshunted and operates in series with: relay E in the will known manner, the latter remaini inert due to its marginal adjustment. Re ay 1) closes the talking circuit and sleeve circuit through to the r ushes 203,209, 207, and cuts off relay A. to the sleeve terminal, which is held grounded from the connector in the well known manner. are stepped to the eleventh position and a set of cam springs 211 operates and substitutes busy tone from source ET for the ound on the winding of relay A applied t rough the secondary of dial tone source DT connected to the line as soon as relay .3. in the line finder operates, to inform the subscriber the circuits are ready for dialing. When the calling line is refused connections on certain levels of the selector, the ground heretofore referred to applied to conductor 180, 212 is extended by switch 213 closed on these levels by the switch shaft to the test brush 207, and this results in the selector operating as though it found all the trunks in this level busy, and returns a busy signal to the calling party from the all trunks busy source B.

When the selector brushes 203, 209, 207 pick out an idle connector, the impulse reay 214 thereof is operated toset the same on the desired line in the 'well known manner. Battery for talking purposes is fed to the calling line through relay 214 and-to the called line L through relay 215.

The release is controlled by the calling party, and upon his replacing the receiver, relay 214 releases and removes holding ground fromthe sleeve wire, which releases the connector in the well known manner. The removal of this ground, by releasing relay D, closes the circuit of release magnet 216 in the well known manner to restore the selector. Y

The line finder is released by the ground applied to release control conductor 217 due to the release of relay D. This ground is applied over the upper most armature of relay D, armatures and back contacts of relays B, A, conductor 217, conductor 191,

ofi-normal switch 165, tov the left winding If all trunks are busy the brushes Relay D is now locked I ay A disconnects the talking brushes from the trunk during release to prevent interference, and closes the following circuit to the release ma st 192: battery, 192, 151, 150,125, 126, 12 ,108, 120,107,106, ground. The release magnet armature applies ground to conductor 164 to close a secon locking circuit for the left winding of relay B independently of ground at 165 and this ground also closes a second circuit for relay F to hold the same" operated independently of its energizingcircuit traced to ground at off-normal switch 165. When the shaft restores, off-normal switch 1 165 by opening its uppermost contact restores relay A. Relay A in releasing opens the circuit of the release magnet. The release magnet in retracting its armature opens the locking circuit of relay B. The retraction of the release armature also opens the holding circuit through the left winding of relay F.

Relay 195 is provided 'to disconnect the oup relays G from battery when all the fiiiders are busy. This relay is operated by a circuit including the armatures 196 and front contacts of relays F of the operated finders in series, as shown and descrlbed in detail in Patent No. 1,27 8,245 of September 10, 1918 to A. B. Sperry. I

The called multiple terminals of line X are shown at 199 and the line X is also multi led to a jack 197 before an operator, who may extend calls to the line by the plug 198. When a connection is made to the line at either set of multiples, the cutoff relay 00 operates to cut off the line relay LR to prevent starting a finder upon the response of the called party.

What is claimed is:

1. In a telephone system, subscribers lines, a trunk line, a finder switch in which said trunk terminates, having a pair of sets of brushes, means for moving said brush sets over two rows of subscribers line terminals simultaneously upon the initiation of a call, means for testing terminals in both rows simultaneously and for stopping the finder when a calling line is reached in either row, means always including but a single relay for connecting the proper brush set to said trunk, means for operating said relay to shift the trunk to one brush; set when a calling line is reached by said set, and means for stopping said finder without operating said relay when a calling line in the other group is reached by the other brush set.

2. In a telephone system, subscribers lines,

atrunk line, a finder switch in which said trunk terminates having a. pair of sets of brushes, means for moving said brush sets over two rows of subscribers line terminals 7 simultaneously upon the initiation of a call,

means for testing one line in each row simultaneously and for stopping the finder when a calling line is reached in either row, means for connecting the proper brush set to said trunk, said means consisting of a relay, shunt circuits for maintaining said relay inert until a calling line is reached, means to operate said rela to shift the trunk to one set when a cal ing line is reached by said set, and means for stopping said finder without operating said relay when a callin line in the other group is reached by said other set.

3. In a telephone system, subscribers lines, a trunk line, a finder switch in which said trunk terminates having a pair of sets of brushes, a normally grounded test terminal for each subscribers line in said finder, means for removing said ground from the terminal of a line when said line is calling, means for movin said brush sets over two rows of termina s simultaneously upon the initiation of a call, means for testing two lines in said rows simultaneously and for stopping the finder when a calling line is reached in either row, means for connecting the proper brush set to said trunk, said means consisting of a relay, shunt circuits including non-calling test terminals for maintaining said relay inert until the calling line is reached, an operative circuit for said relay thereupon closed to cause the same to shift the trunk to one set if said set engages a calling line, and means for stopping said finder Without operating said relay if a non-grounded test terminal in the other group is reached by the test brush of the other set.

4. A testing circuit arrangement for an automatic line finder having two sets of brushes each including a test brush, comprising a relay, a magnet operable to move said brush sets in unison, a circuit for said magnet including one test brush, a circuit for said relay including the other test brush, a group of lines, test terminals in said finder for said lines, means actuated upon the initiation of a call by any line in the group for changing the normal electricalc'ondition of its associated test terminal, means for operating said magnet to cause said test brushes to simultaneously pass over the test terminals of the lines in said group in pairs, means responsive to the normal electrical condition on the test terminal of one noncalling line for operating said relay, means including a front contact of said rela responsive to the normal electrical con ition on the test terminal of the other non-calling line for reoperating said magnet to continue relay, a ma net, a circuit the brush movement, and means controlled b said magnet in operating for opening tli e relay circuit to release said relay whereby said magnet is in turn released and the interaction of said relay and magnet is continued until the test terminal of the calling line is reached,

5. In a line finder, telelphone lines arranged in two groups, each me having talking terminals and a test terminal, two sets of brushes in said line finder each set including a test brush and a pair of talking brushes, means res onsive to the initiation of a call on an ine in either group for advancing said rush sets to the terminals of the first line in each group, a marginal or operating said margina relay controlled by said magnet and completed via the test brush of one brush set and the test terminal of the first line in one group provided said line is noncalling, a circuit for operating said magnet said circuit being extended by said marginal relay in operating and com leted via the test brush of the other brus set and the test terminal of the first line in the other group provided said line is non-calling, said ma net in operating advancing the two sets of rushes to the terminals of the second line in each group and so on, a sensitive relay operable in series with said marginal relay but shunted over a circuit including said test brush and the test terminal of an non-calling line over which said test brush advances to prevent said sensitive relay from operating, a trunk switching relay operable in series with said magnet but shunted over a circuit including said other test brush and the test terminals of any noncalling line over which said other test brush advances to prevent said switchin relay from operating, and means for altering the electrical condition on the test terminal of any line which is calling so that either the shunt around the sensitive or around the switching relay, as the case ma be, will be removed when the test termina of the calling. line is encountered permitting the relay thus afiected to operate and likewise preventing the further operation of the magnet.

6. In a line finder, tele hone lines arranged in two groups, each me having talking terminals and a test terminal, two sets of brushes in said line finder each set including a test brush and a pair of talking brushes, means res onsive to the initiation of a call on an me in either group for advancing said rush sets to the terminals of the first line in each group, a marginal relay, a magnet, a circuit for operating said marginal rela controlled by said magnet and complete via the test brush of one brush set and the test terminal of the first line in one group provided said line is noncalling, a circuit for operating said magnet,

said circuit being extended by said marginal relay in operating and comleted via the test brush of the other brus .set and the test terminal of the first line in the other group provided said line is non-calling, said magnet in operating advancing the two sets of )rushes to the terminals of the second line in each group and so on, a sensitive relay operable in series'with said marginal relay but shunted over a circuit including said test brush and the test terminal of an non-calling line over which said test brus advances to prevent said sensitive relay from operating, a trunk switching relay 0 erable in series with said magnet but s iunted over a circuit including said other test brush and the test terminals of any non-calling line over which said other test brush advances to prevent said switching relay from operating, and means for altering the electrical condition on the test termina of any line which is callin so that the operating circuit for the marginal rela or for the magnet, as the case may be, wi 1 be opened when the test terminal of the calling line is encountered preventing the further operation of the magnet.

7. In a telephone system, a line finder; telephone lines arranged in two groups, each line having talkin terminals and a test terminal, two sets of brushes in said line finder each set including a test brush and a pair of talking brushes, means res onsive to the initiation of a call on any ine in either group for advancin said brush sets to the terminals of the rst line in each group, a marginal relay, a magnet, a circuit for operating said marginal relay controlled by said magnet and com leted via the test brush of one brush set an the test terminal of the first line in one group provided said line is non-calling, a clrcuit for operating said magnet, said circuit being extended by said marginal rela in operating and completed via the test rush of the other brush set and the test terminal of the first line in the other group provided said line is noncalling, said ma net in operating advancing the two sets ofgirushes to the terminals of the second line in each roup and so on, a sensitive relay 0 erable in series with said marginal relay ut shunted over a circuit including said test brush and. the test terminal of any non-calling line over which said test brush advances to prevent said sensitive relay from operating, a trunk switching relay operable in series with said ma at but shunted over a circuit including said other test brush and the test terminals of any noncalling line over which said other test brush advances to prevent said switchin relay fromoperating, a trunk circuit, an means for altering the electrical condition on the test terminal of any line which is calling so that the. operating circuit for the marginal relay or for the m?net, as the case trunk via the contacts of the trunk switchmay be, w1ll be opened an either the shunt mg relay 1n either its operated or its normal around the sensitive relaieor that around condition to the calling line.- 1 the switching relay will removed when In witness whereof, I hereunto subscribe I the test terminal of the calljizttgll hne is am my name this 13th day of April, A. D. 1928.

countered preventing the in er advance of the switch brushes and connecting said ALFRED E. HAGUE.

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