US1799485A - Telephone system - Google Patents

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Publication number
US1799485A
US1799485A US324816A US32481628A US1799485A US 1799485 A US1799485 A US 1799485A US 324816 A US324816 A US 324816A US 32481628 A US32481628 A US 32481628A US 1799485 A US1799485 A US 1799485A
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United States
Prior art keywords
line
wiper
wipers
switch
contacts
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Expired - Lifetime
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US324816A
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English (en)
Inventor
Rudolph F Stehlik
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Reserve Holding Co
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Reserve Holding Co
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Publication date
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Priority to US324816A priority Critical patent/US1799485A/en
Priority to GB37058/29A priority patent/GB344362A/en
Priority to FR37802D priority patent/FR37802E/fr
Application granted granted Critical
Publication of US1799485A publication Critical patent/US1799485A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

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    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q3/00—Selecting arrangements

Definitions

  • vThis invention A relates general lto auto@ niatsic ⁇ telephone systems, more particularly to .such systems in whichrfnder switch .IneCh- Y have employed one oratwo-relays :tor eachline inthe system, :these :relays .being individual to the line and permanently Yassociated with it.
  • the line initiates fa call @ne .of the relays operates to -,start the finder switch mechanism to V.establish a connection with the line.
  • the connection is established the other relay is operated to cut off the first yrelay and clear the line to permit switch operation and conversation.
  • a relay is not an expensive .devi-ce but when -a relayis employed for each line, :a .large ymlmber of such relays are required :in a system of 'any size,
  • PrOVlde a .constantly moving line equipment of 100 line ⁇ capacity together with 100 ypoint lfinder switches yand circuit arrangements enabling 'the' line equipment to control the Inders briefly stated, is theV through two motions to establish a ,connec-r tion with a calling line.,-
  • Fig. 2 I show iincler F'which isa well known ⁇ rowger two motion 'finder .switch whose wipers move flirst in a vertical direction to'select a level containing a calling line and then in ahorizontal direction to select a particular line inthe level.
  • iincler F' which is a well known ⁇ rowger two motion 'finder .switch whose wipers move flirst in a vertical direction to'select a level containing a calling line and then in ahorizontal direction to select a particular line inthe level.
  • thernovements of the wipers are con? e .trolled solely by the control equipment, ⁇ ,that
  • Fig. 2 also shows the relays 1 to 11, inclusive, which are divided into five groups, one for each set of wipers of the line equipment.
  • Relays 1 ⁇ and2 are associated with the wipers 30 to 34 inclusive of the first line eqlpipment, the relay 2 being a line relay w ich is thrown across the subscribers loop and energized if that group is shorted, that is if the receiver is off the hook.
  • Relay 1 is a cut-olf relay which is energized each time the private wiper P1 encounters the contacts of a busy line, in a manner which will be pointed out in detail hereinafter.
  • relays 3 and 4 are associated with the wipers to 38, rela-ys 5 and 7 with the wipers 39 to 42, relays 8 and 9 with the Wipers 43 to 46, and'relays 10 and 11 with wipers 47 to 50.
  • Relay 5 is common to the entire group of line equipments, and is energized when one of the equipments is taken into use to disconnect the private wipers P1, P2, P3, P4, and P5 from their respective cutoff relays to prevent energization of those cut-off relays until the finder then being operated is completely set.
  • the wipers 30 to 34, inclusive have access to lines O1, 91, 81, 71, 61, 51, 41, 31, 21 and 11, and also the lines 02, 92, 82, 72, 62, 52, 42, 32, 22 and 12.
  • these Wipers have access to lines 1 and 2 in each of the ten levelsin the banks of sis , to 42 have access to lines 5 and 6 ineach of the levels.
  • Wipers 43-46 have access to lines 7 and 8 in each of the ten levels and Wipers 47 to 50, inclusive, have access to lines 9 and 10 in each of the ten levels.
  • Wiper group 1 comprising wipers 30 to 34, inclusive, contains five wipers, designated as the positive line, negative line, private, the vertical wiper, and the B wiper.
  • the two line wipers positive and negative land the private wiper need no detailed explanation since their function is the same as similarly named wipers in any well known Strowger automatic telephone system.
  • the vertical or V wiper is the wiper through which the vertical movement of the finder switch is controlled and the B wiper is the wiper through which thev rotar movement of the finder is controlled. ince the vertical tiates a call and that the wipers 30 to 50 ro-' tating from left to right encounter the contacts to which the line A is connected.
  • the line relay associated with the wipers 39 and 4 0 will have its circuit closed through the Yhook switch and instrumentalities of the substation A, and finder F, which has'been preselected by distributor D-will be started in search of the callingV line. At the Sametime that wipers 39 and 40 are engaging contact wiper 33 is engaging contact a.
  • a circuit is completed through the vertical wiper'33 and contact a to the vertical magnet of the finder F, to energize that magnet to elevate the shaft of the finder one vertical step.
  • I/Vipers 30 to 50 inclusiv-e, move on to the right at a uniform rate of speed.
  • the circuit of the' vertical magnet of the finder F is opened to permit that magnet to fall back preparatory to taking another step. ⁇ When the wiper 33 engages contact the circuit of the vertical magnet of the iinder is again closed'and the shaft elevated another step vertically.
  • circuit' for the switchthrough relay of the iinderoperating it to establish a line.. ⁇ The 'operation of the .switchfthrough relay of the finder controls the .distributor D to step off of the contacts leading to the finder F and to start Vit in Search of another finder in that group, preselecting that iinder and preparing circuits through which it Will to the initiation ot the neXt'call in the line group. Y.
  • Wiper 38 Jfour contacts the controlling ofthe vertical movement of thender is by the Wiper iregardless .of thel control equipment handling the call, and that the B Wipers control the rotary movement of the finder through the opposite half of the bank from that containing the con- .tacts Vof the calling line. The reason for this will be apparent when it is remembered that the line vequipment comprising Wipers 30 to 50, inclusive, is constantly moving .and does not change its pace or stop during .the setting of a call.
  • switch ground is placed on to the priva-te Wiper V52 by the spring 93 of the switch through relay 14 of the finder to extend a circuit through that my co-pending applicay l have provided cut-off relays 10, each associated with one of Y* Wiper and the private contact and release trunk engaged thereby, to the P contact in thel bank of the line equipment associated with that line.
  • cut-off relays 10 each associated with one of Y* Wiper and the private contact and release trunk engaged thereby, to the P contact in thel bank of the line equipment associated with that line.
  • the line contacts relay 6 will be energized before the line wiper engages their contacts and there will be no click in the line when these Wipers engage since they are connected to nothing and do not bridge from one contactset to another. If the line 7 5 happens to be taken for use by the connector the private contacts CP in the bank of the connector will be grounded by that switch and circuit of the cut-off relay 6 will be closed as before. Thus it will be seen that lines already in use will not be interfered with in any way by the passing of the line equipment wipers over their contacts.
  • Line A initiates a call Assume now that the line A initiates a. call by removing the receiver from the switch hook to complete a circuit through the telephone to the line conductors leading to the line equipment. It will be noted that these line conductors terminate only in benl: contacts, those contacts being in the banks of the finder switches, the banks of the connector and the banks of the line equipment.
  • the wipers of the control equipment happen to be standing on the con ⁇ tacts of that line at the instant. Since each wiper has access to twenty contacts it will happen more often that the wipers will be elsewhere when the line initiates a call.
  • Relay energizes over this circuit and at spring 73 breaks a point in the locking chain of the succeeding line relays and locks itself from battery through its lower winding, spring 73 and its malte contact, spring 68 and its break contact, spring 63v and its break Contact, through the winding of relay 18 through the breal: Contact of spring 100 to ground. Relay 18 energizes in this circuit and relay 7 is locked in its energized position.
  • relay 18 closes the obvious circuit through the win ding of 'relay 21 oi the distributor equipment D, to energize that relay for a purpose which will be hereinafter pointed out.
  • relay 18 closes a circuit from ground through multiple paths, the one leading through the lower winding of relay 10 the lower winding of relay 8, and the winding of relay 5 in series t0 battery, to energize relays 5, 8 and 10.
  • the other multipled path leads through the lower winding of relay 6, the lower winding of relay 3. and the lower winding of relay 1 to battery to energize relays 1, 3 and 6. It will be seen that responsive to the energization of relay 7, relays 18, 21, 1, 3, 5, 6, 8 and 10 have all been energized.
  • Relay 5 at the springs controlled by it opens the private wipers oit' the line equipment so that no further tests are madeby the distributor and line equipment during the setting of the present call.
  • Relays 1, 3, 6, 8 and 10 are energized to remove the ground and battery connections from the positive and negative line wipers of the line equipment so that lines which may be in use will not be interfered with while the private wiper circuits are olisabled.
  • Relay 7 being locked independently ot the springs 70 and 71 will not fallback at the moment.
  • relay 21 prepares a locking circuit for the relays 19, 20 and 22 by closing springs 106; and prepares a point in the circuit of the distributor motor magnet 24 by closing springs 105.
  • relay 21 closes a circuit from ground through wiper 55, through the winding ot' relay 13 to battery.
  • Relay 13 energizes over this circuit to open a point in the finder release circuit at springs 87 and to prepare points in the finder switch through circuits at springs 88 and 92.
  • lVhen relay 18 energizes a circuit is closed from ground through springs 97 and the vertical impulse conductor V, wiper 33, contact a, which is in line with the line contacts from which the instant call is initiated, and therefore simultaneously engaged by the wipers, vertical interrupter conductor 142, and thence over parallel paths, the one through springs 110, through the winding of relay 23 to battery, and the other through spring 111, wiper 57, through the winding of the vertical magnet 16 to battery.
  • Relay 23 energizes over this circuit, locking itself over a circuit traceable from ground through springs 96, springs 95, wiper 56, springs 112, through the winding of relay 23 to battery.
  • the vertical magnet 16 energizes over the above circuit, and is locked energized independently over the wiper 33, over the circuit just traced from the wiper 56 to springs 112, thence through springs 110 and 111, vthrough the previously traced path to the vertical magnet 16.
  • the vertical magnet 16 is fully energized the locking path of that magnet5andithefrel ⁇ ay ⁇ 23 isbrokenand if thek wiper 33 has passed olfl to the-contact a thatrel'ay and magn'etwill fall back.
  • relay 22 closes a circuit from ground through spring 74 and the conductor-B3 to kthe -wiper 42 which is nowinengagement with contact 7i of the bank.
  • This circuit 'extends through the'contact and the rotary interrupter conductor land thence over'parallelpaths, the one through conductor 140, through spring 103 and the winding of relay 20- to battery, thesecondthrough spring 110 'and the winding. of relay 23 to battery,y and the third throughl conductor 1'44,-wiper 58 and the ro'- tary magnet 17 to battery.
  • Relay 20 upon energizing locks itself throughv springs 103 and 106 to ground, and' aty springs 102 prepares a point in the switch-through circuit, f' of the' finder.
  • ' Relay 23 energizesas before and at spring 112 locks itself yto'ground through the interruptersprings 95 and' 96 of the finder'F,jthisground ⁇ circuit also e-X- tending through springs 1121and1110 to the junction' of the conductors 140 and 144 to lock the' rotary'magnet circuit independently of the wiper 4.2 so that the rotary magnet is insured of fulloperation.
  • relay 14 applies ground through the wiper 52 and the release-trunk Cnnductor associated with the line A to protect the line from intrusion eitherby al connectoror byv theV linee uip- .ment
  • the release' ⁇ trunk ack from the selector is extended throughv the relay 14so that when the release trunk is grounded by theselector the well known manner relay 1 4 isl'locked ⁇ energized to that groundedconductor ⁇ to rmaintain the finder in its switch through positionfaslon'g as the connection is wanted.
  • relay 1 4 isl'locked ⁇ energized to that groundedconductor ⁇ to rmaintain the finder in its switch through positionfaslon'g as the connection is wanted.
  • springy 89 relay 14 opens a point inthe release circuit of the finder. i L
  • the distributor prese'lect's an alle ytder
  • the deenergization of relay 18- at springs v99 opens the point in thecircuit of slow-torelease relay 221, which falls backY after an interval and at springs y106 opens the locking circuit of relays 22,. 20 and 19.
  • relay 21 opens thecircuit over which magnet 241of the distributor was energized to'permit that magnet to deenergize and advance the wipers of the distributor one step.y If the next finder of the group happens to lbe Vidle no further sten -inGfis-ne'cessar but if it is busy a circuitwill be completed from ground on springs 88, off-normal springs 86,
  • a plurality of subscribers lines terminating in bank contacts, the contacts of said banks being arranged in groups, a finder switch having access to said lines, a constantly moving line equipment also having access to said lines, means for associating said finder with said line equipment and means in said line equipment responsive to the initiation of a call by one of said lines for directively operating said iinder first to select the group containing the calling line and then to select the calling line from that group.
  • a plurality of subscribers lines terminating only in bank contacts, a two coordinate finder switch having access to said lines, and means common to said lines responsive to the initiation of a call onY one of them for directing said finder through said two coordinate motions to establish a connection with said line.
  • subscribers lines subscribers lines, a line equipment having a plurality of sets of wipers, a finder switch having a primary and a secondary motion, a primary test wiper in said line equipment, a secondary test wiper in each of said wiper sets, means responsive to the association of a set of said equipment wipers with a calling one of said lines for directing 'the primary movement of said finder switch under the control of said primary test wiper, and means controlled thru the secondary test wiper of the set associated with the calling line for directing the secondary motion of said inder to establish a connection with said line.
  • a telephone system subscribers lines, a line equipment having a plurality of sets of wipers, a finder switch having a primary and a secondary motion, a primary test Wiper in said line equipment, a secondary test wiper in each of said wiper sets, means responsive to the association of one set of said equipment wipers with a calling one of said lines for directing the primary movement of said finder switch under the control of said primary test wiper to operate the finder a number of steps in its primary movement dependent upon the position of the primary test wiper when said line was found calling by said set of equipment wipers, means con-y trolled through the secondary test wiper of the set associated with the calling line for directing the motion of the finder a number of steps in its secondary movement depending on the position of that test wiper when said line was found calling by the said set of equipment wipers, and means associated with said iinder for establishing a connection with said line.
  • a plurality of subscribers lines designated by tens and units digits a line equipment having a bank of contacts and wipers sweeping over said contacts, said lines being so arranged in said bank that said wipers simultaneously test the lines of odd units designationin retrogressive order of their tens designation then test the lines of even units designation in retrogressive order of their tens designation,
  • a plurality 'of subscribers lines designated by tens and units digits a line equipment having a bank of contacts and wipers sweeping over said contacts, said lines being so arranged in said bank that said wipers simultaneously test the ⁇ lines of odd units designation in retrogressive order'of their'tens designation then test the' lines of even units designation in retrogressive and'lof their tens designation, a finder switch liavingi accessi to said lines, means in saidline equipmentfor testing said lines for'calling condition, and means responsive ⁇ to the'finding of two simultaneously' calling lines by said line equipment for directingzsaid finder to tlie'one of t'liosegline's having they lower' units designation'.
  • said line equipment means responsive to the picking up of an' initiated callby' saidk line'wipers for extending a circuit throughv said primary control-wiper and said primary magnet tooperatefthe magnet a' number of times dependent upon the posif ti'on of said line wipers when said calling line was encountered, means operatedl when said' wipers reach' a predetermined position for breaking said primary circuit and for establishing a circuit through sai-d secondary magnet-and wiper to operatethat wiper and magnet' a predetermined number of' steps dependent uponthe positiony of said line'wipers when said calling line was encountered, means' responsive' to thel operationof said magnet-ster positioning'said finder upon said calling: line, and means for establishing a connection therewith;v
  • said linesV for seizing said line equipment for'tlie exclusive use of that call" when said wipersz encounter' the line, aiidnieans con ⁇ trolled thrusaidfline equipment wipers and dependent" upon thef set of wipers used and the position of that set when the-calling line is encountered for directing said finder to establish ai connection withthat line.
  • aA telephone system a plurality of subscribers lines divided into groups,l aecommoii line relay anda common' cut-olf relay for eachy group of lines, an autoniaticswitch common to said' lines and' having av set of wipers for each group, means for operating saidiswitch, means responsive to a set of said wipersv encounteringk a callingv line Jfor energizing the line: relay associated with the group-'iii which the calling'li-iie is located, and :C
  • a'plurality ot subscribers lines having access to said lines, an auxiliary switch for finding a line when calling, said auxiliary switch continuing to operate after connecting with the calling line, and means controlled by the continued operation of said auxiliary switch for directively operating one ot said inders in its two.movements to iind said calling line.
  • a group of telephone lines connected only to the contacts of switch banks, two-motion directively controlled finder switches having access to certain of said contacts, control equipment for said finders, a constantly moving switch for associating said control equipment with certain other ot' said contacts, means responsive to the association of said equipment with the contacts of a calling one of said lines for f thereafter causing said constantly moving switch to generate impulses, and circuit connections over which the impulses generated by said constantly moving switch are delivered to one of said finders to directively operate it in its two movements to the contacts of said calling line.
  • 1S. In a telephone system, a plurality ot lines, a directively controlled two-motion automatic switch having access to said lines, a single motion auxiliary switch having access to said lines, said auxiliary switch operating to yconnect with one of said lines when calling, and means for causing both said switches to move together after the auxiliary switch connects with the calling line and until the automatic switch is directively operated in its two movements into connection with the calling line.
  • the combination ot a plurality of subscribers lines terminating in a switch bank and having tens and units designations in accordance with the position of the bank contacts in which such lines terminate, of a second switch bank in which said lines terminate in bank Contact groups each oit which comprises only the bank contacts of the lines having the same units designation, and means :for simultaneously testing all the lines in said groups having even units designations and the same tens designation.
  • the combination or a plurality of subscribers lines terminating in a switch bank and having tens and units designations in accordance with the po sition of the bank contacts in which such lines terminate, of a sec-ond switch bank in with a calling one of said lines, said linesV terminating in the bank of the finder switch in groups, each iinder line group consisting v bank of contacts and wipers sweepingpover said contacts, said lines also terminating in the bank of the line equipment in groups, each line equipment group consisting ofthe lines having the same unit-s designation but different tens designations arranged in a definite order, and means responsiveto the wipers of the line equipment encountering the bank contacts of a calling line for operating said finder switch in its two movements to the finder bank contacts of the calling line in accordance with the position of the bank contacts of the calling line in the line equipment bank.
  • an impulse sender for directively operating a two-motion switch in a primary and then a secondary movementl to complete a connection ⁇ a primary wiper, a plurality of secondary wipers, means for operating said wipers, means controlled by said primary wiper 'for determining the number of primary impulses to be transmitted to said switch, means for selecting one of said secondary wipers, and means dependent upon selected secondary wiper for determining the number of secondary impulses to be transmitted toV said switch.
  • a normally inactive primary wiper for directively operating a two-motion switch in a primary and then a secondary movement to complete a connection
  • means for operating said wipers means for rendering said primary wiper active, means dependent upon the position of said primary wiper at the time such wiper becomes active for ⁇ determining the number of primary impulses to be transmitted to said switch, means for thereafter rendering only one of said secondary wipers active, and means dependent upon the selected active secondary wiper and dependent upon the' position of the primary wiper at the time such wiper became active for determining the number of secondary impulses to be transmitted to said switch.
  • a normally inactive primary wiper passing over a deinite number of primary bank contacts' in succession, a plurality of normally inactive secondary wipers each passing over a number of secondary bank contacts, means for rendering Said primary wiper active, means dependent upon the position of thev primary wiper at the time such wiper becomes active for determining the number of primary impulses to be transmitted to said switch, means responsive to the primary wiper engaging the last of said primary contacts for rendering only one of said secondary wipers active, and means dependent upon the selected active secondary wiper for determining the number of secondary impulses to be transmitted to said switch.
  • a normally inactive primary wiper passing over a definite number of primary bank contacts in succession, the last of said contacts being a changeover contact for controlling the changeover of said Switch from its primaryv to its secondary motion, a plurality of normally inactive secondary wipers each passing over a number of normally inactive secondary control contacts and a normally inactive switch through contact, means for rendering said primary wiper active, means dependent upon the position of the primary wiper at the-'time such wiper becomes active 'for determining the number of primary impulses'to be transmitted to said switch, means responsive to the primary wiper encountering said changeover contact for rendering said secondary contacts, said switchnthrough contacts, and only one of said secondary wipers active, and means dependent upon the selected active secondary wiper for determining the number of secondary impulses to be transmitted to said switch.
  • a switch bank having a definite number of primary contacts, a plurality of groups of active secondary contacts, a switch-through contact associated with each group of secondary contacts, multiple connections between said primary contacts, multiple connections between said active secondary contacts, and multiple connections between said switch-through contacts, each secondary group' comprising a different definite number of active secondary contacts, and wipers cooperating with said lcontacts to control the transmission of impulses by said sender.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Structure Of Telephone Exchanges (AREA)
  • Monitoring And Testing Of Exchanges (AREA)
US324816A 1928-12-10 1928-12-10 Telephone system Expired - Lifetime US1799485A (en)

Priority Applications (3)

Application Number Priority Date Filing Date Title
US324816A US1799485A (en) 1928-12-10 1928-12-10 Telephone system
GB37058/29A GB344362A (en) 1928-12-10 1929-12-03 Improvements in or relating to telephone systems
FR37802D FR37802E (fr) 1928-12-10 1929-12-10 Perfectionnements aux systèmes téléphoniques

Applications Claiming Priority (1)

Application Number Priority Date Filing Date Title
US324816A US1799485A (en) 1928-12-10 1928-12-10 Telephone system

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US1799485A true US1799485A (en) 1931-04-07

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US324816A Expired - Lifetime US1799485A (en) 1928-12-10 1928-12-10 Telephone system

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US (1) US1799485A (fr)
FR (1) FR37802E (fr)
GB (1) GB344362A (fr)

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2540644A (en) * 1944-01-12 1951-02-06 Automatic Elect Lab Allotter switch for preassigning idle finder switches
US2557638A (en) * 1947-01-07 1951-06-19 Int Standard Electric Corp Telecommunication system
US2898407A (en) * 1957-06-05 1959-08-04 Gen Dynamics Corp Electronic telephone system
US3228003A (en) * 1962-03-20 1966-01-04 Ibm Matrix search device

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2540644A (en) * 1944-01-12 1951-02-06 Automatic Elect Lab Allotter switch for preassigning idle finder switches
US2557638A (en) * 1947-01-07 1951-06-19 Int Standard Electric Corp Telecommunication system
US2898407A (en) * 1957-06-05 1959-08-04 Gen Dynamics Corp Electronic telephone system
US3228003A (en) * 1962-03-20 1966-01-04 Ibm Matrix search device

Also Published As

Publication number Publication date
FR37802E (fr) 1931-01-24
GB344362A (en) 1931-03-03

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