US2261370A - Telephone system - Google Patents

Telephone system Download PDF

Info

Publication number
US2261370A
US2261370A US335241A US33524140A US2261370A US 2261370 A US2261370 A US 2261370A US 335241 A US335241 A US 335241A US 33524140 A US33524140 A US 33524140A US 2261370 A US2261370 A US 2261370A
Authority
US
United States
Prior art keywords
relay
sender
line
terminating
marker
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Expired - Lifetime
Application number
US335241A
Other languages
English (en)
Inventor
Ralph E Hersey
Ottman H Kopp
James B Newsom
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
AT&T Corp
Original Assignee
Bell Telephone Laboratories Inc
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Priority to BE483523D priority Critical patent/BE483523A/xx
Priority to FR961957D priority patent/FR961957A/fr
Application filed by Bell Telephone Laboratories Inc filed Critical Bell Telephone Laboratories Inc
Priority to US335240A priority patent/US2259101A/en
Priority to US335241A priority patent/US2261370A/en
Priority claimed from US335245A external-priority patent/US2259100A/en
Application granted granted Critical
Publication of US2261370A publication Critical patent/US2261370A/en
Anticipated expiration legal-status Critical
Expired - Lifetime legal-status Critical Current

Links

Images

Classifications

    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q3/00—Selecting arrangements
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04M—TELEPHONIC COMMUNICATION
    • H04M3/00—Automatic or semi-automatic exchanges
    • H04M3/60—Semi-automatic systems, i.e. in which the numerical selection of the outgoing line is under the control of an operator
    • H—ELECTRICITY
    • H04—ELECTRIC COMMUNICATION TECHNIQUE
    • H04Q—SELECTING
    • H04Q3/00—Selecting arrangements
    • H04Q3/0004—Selecting arrangements using crossbar selectors in the switching stages

Definitions

  • This invention relates to telephone exchange systems and more particularly to systems of the so-called cross-bar type for enabling the terminating equipment to be used in common for terminating calls in two oiiices serving a maximum of twenty thousand directory numbers.
  • each of the oiiices is provided with switching equipment for establishing connections from subscribers lines terminating therein to other lines which may terminate in the sameor another office and is provided with originating sender and marker equipment for controlling a portion of the switching equipment on calls originating in the office and with terminating sender and marker equipment for controlling a further portion of the switching equipment to terminate calls incoming to the oce.
  • switching equipment for establishing connections from subscribers lines terminating therein to other lines which may terminate in the sameor another office and is provided with originating sender and marker equipment for controlling a portion of the switching equipment on calls originating in the office and with terminating sender and marker equipment for controlling a further portion of the switching equipment to terminate calls incoming to the oce.
  • two oices may be located in the same oiiice building and a considerable saving in equipment could be realized if the terminating equipment could be used in common for both offices.
  • the trunks incoming to such common terminating equipment serving two oiiice units may be rarranged in a common group selectable at an originating oice in response to the dialing of the oflice code digits of either of the terminating office units or may, as an alternative, be in separate groups selected in response to the dialing of the respective oiiice codes of the units,
  • the seizure of an incoming trunk is effective to cause the seizure of an idle terminating sender at the combined terminating office through a sender link and, after the numerical digits have been registered in the terminating sender, to
  • the originating sender is modified so that when the common group of trunks has been selected in accordance with the operation of the route relay of the originating marker in response to the dialing of the office code of one of the two office units, for example ofce A, the counting relays of the originating sender will satisfy the incoming group register of the sender after one to four revertive impulses have been received and that when the common group of trunks has been selected in accordance with the operation of the route relay of the originating marker in response to the dialing of the ofce code of the other of the two office units, for example of ofice B, the counting relays will satisfy the incoming group register only after from six to nine revertive impulses have been received.
  • the previously indicated modication of the originating sender is not necessary since the group of incoming trunks seized identifies the destination 55 of the call in either the A or B oice units and this identification is passed over the terminating sender link circuit to the terminating sender and thence to the marker to operate the transfer relay above mentioned.
  • Fig. 1 shows schematically the arrangement of equipment embodying the present invention
  • Fig. 2 shows schematically subscribers lines terminating in an originating oilce, line-link, district and ofiice frames of cross-bar switches for extending connections from such lines, a sender link and control circuit for extending a connection from any district junctor to an idle sender and district and oice frame connectors for associating the district and office frames with a marker;
  • Fig. 3 shows such portions of an originating sender, marker connector and marker as are necessary to an understanding of the invention
  • Figs. 4 to 9, inclusive disclose such portions of the equipment of the terminating office as are necessary to an understanding of the invention
  • Fig. 4 showing schematically a plurality of incoming junctors, an incoming link and connector for associating any incoming junctor with an idle terminating sender, and relay equipment for transmitting an identification of the group of incoming trunks seized for the completion oi a connection to the terminating sender
  • Fig. 5 showing such portions of the terminating sender as are of particular interest in connection with the present invention and a marker connector by which an idle terminating marker is associated with the sender
  • Fig. 6 showing a portion of the terminating marker embodying the invention
  • FIG. 7 disclosing an incoming frame and one number group of each of the two office units served in common by the terminating sender and terminating marker;
  • Fig. 8 showing additional relays and circuits of the terminating marker of Fig. 6 and
  • Fig. 9 showing a plurality of line-link frames in each of two line choices and subscribers lines terminating, respectively, in two office units;
  • Fig. 10 is a chart indicating how the several figures of the drawing should be arranged to completely disclose the invention.
  • the operation of the system is briefly as follows: Upon the initiation of a call, for example on the subscribers line 200, the line is extended by the primary and secondary line switches such as 20l and 202 of the line-link frame to an idle district junctor 203 and through the primary and secondary sender link switches 204 and 205 on the sender link and control frame to an idle originating sender 300.
  • the subscriber dials the wanted line designation the digits of that designation are registered in the sender, an idle marker 302 is attached to the sender by the marker connector 30
  • the marker selects and connects with an ofiice link having access to an idletrunk extending to the wanted omce.
  • the marker then controls the establishment of the connection from the district junctor 203 to the idle outgoing trunk over primary and secondary switches such as 209 and 2l0 on the the line number registered in the marker.
  • the incoming junctor 400 Upon the seizure ot an idle trunk, such as 25. terminating in an incoming junctor 400 at the terminating oiilce, assumed to serve two office units A and B, the incoming junctor becomes associated through the primary and secondary switches 404 and 405 of the terminating sender link frame with an idle terminating sender such as 500.
  • the sender Upon its seizure, the sender proceeds to transmit series of revertive impulses back over the established connection to the originating sender 300 to satisfy the originating sender with respect to the setting of its register which was set in response to dialing to register the numerical digits of the wanted line number.
  • the originating sender 300 will be arranged in such a manner that with a route relay of the originating marker 302 operated in accordance with the office code of the terminating office unit A, it will be satisfied during the transmission of the incoming group series of impulses after from one to four revertive impulses have been received, but that with a route relay of the originating marker operated in accordance with the oiice code of the terminating oflce unit B, it will be satisfied during the transmission of the incoming group series of impulses after from six to nine revertive impulses have been received.
  • the cross-bar register of the terminating sender 500 will, due to its setting, determine in which office unit the call should be terminated and will transmit this information to the associated terminating marker to operate a transfer relay therein. If it be assumed that each terminating ofiice unit may be reached over a separate group of incoming trunks.
  • the originating sender 300 will not be arranged as just described but information with respect to the desired oflice unit will be transmitted to the terminating sender 500 in accordance with the incoming frame on which the selected group of incoming trunks terminate and this infomation will then be transmitted to the terminating marker to operate the transfer relay thereof.
  • the marker rst selects the number group frame
  • the marker then proceeds to associate itself over an incoming frame connector 103 and a line-link frame connector 923 with the incoming frame in which the calling junctor terminates and with the proper line-link frame in which the wanted line terminates and to control the completion of the connection from the calling incoming junctor over the primary and secondary switches 100 and 10
  • rI'he circuits of the originating and terminating ofdces are in general similar to those fully disclosed and described in Patent 2,089,921, granted August 10, 1937 to W. W. Carpenter, the circuits of the terminating oiiice being, however, modified in accordance with the circuits disclosed in the Patent No. 2,232,371 granted Feb. 18, 1941, to J. W. Dehn and O. Myers, but the circuits of both the originating and terminating oices have been further modified to embody the present invention.
  • a call is initiated on calling line 208 and that the calling subscriber desires a connection to line 930 terminating in office unit A of the combined terminating oce.
  • the calling line is connected to an idle district junctor such as 203 over an idle link such as 2
  • the calling subscriber receives the usual dial tone and proceeds to dial the digits of the oice frames are operated to complete the cirrectory number of the wanted line 930 whereupon these digits are registered on the cross-bar register equipment of the sender.
  • the cross-bar register equipment of the sender In order to simplify the disclosure, only such portions of the thousands vertical 303 and of the hundreds vertical 304 of the cross-bar register of the sender are disclosed as are necessary to illustrate the present4 invention.
  • an idle originating marker 302 is associated with the sender through the operation of the usual marker connector 30
  • the marker now proceeds to associate itself over the district frame connector 2
  • the marker then proceeds to test for idle links on the district frame to which the calling district junctor 203 has access, to test for idle oice trunks, to
  • this circuit path may be extended from the district junctor 203 over the primary switch 209, link 206, and secondary switch 2
  • Trunk 2 l5 having been selected as previously described, the incoming junctor 400 functions to associate itself with an idle terminating sender 500, portions of which are disclosed i-n Fig. 5, over a primary switch 404 and a secondary switch 405 of the incoming link and sender connector frame in the well-known manner.
  • this is accomplished by the operation of a group start relay 401, common to a group of incoming junctors such as the group including junctors 400 and 40
  • a test is then made for an idle sender and subgroup relay 409 of a subgroup of terminating senders, in which an idle sender is located, is operated followed by relay 502 individual to the idle sender.
  • the primary and secondary switches 404 and 405 of the sender connector frame are then operated to connect the calling junctor 400 with the selected idle sender.
  • relay 408 Under the assumption that both oce units may be reached over a common trunk group represented by the operated trunk group relay 408, the front contacts of relay 408 will both be connected to ground. The upper armature of relay 408 will be connected over conductor 4I0, the
  • relay 502 of the terminating sender 500 either relay 501 or 508 will be operated over conductor 503 or conductor 504 to indicate to the sender whether the number of the incoming frame is under or over ten and relay 509 will be operated over conductor 506 to indicate to the sender that a trunk of a group common to two oiiice units has been seized.
  • 'I'hese relays if operated, lock under the control of off-normal relay 5
  • Both relays S01 and 503 and both relays 509 and I0 should not be simultaneously operated and therefore with relay 509 operated and either relay 501 or 508 operated, a circuit lis established for relay 5I2 extending from battery through the winding of relay 5I2, upper front contact of relay 509, back contact of relay 5I0, back con-l tact of either relay 501 or 503 dependent upon which is unoperated, thence to ground.
  • Relay 5I2 operates, locks under the control of relay 5I I and conditions the sender for operation.
  • the terminating sender proceeds to register the incoming frame infomation transmitted from the incoming link, a portion of which has been indicated by the operated condition of either relay 501 or 500 and to transmit series of revertive impulses to the originating sender 300 of Fig. 3 to satisfy the sender with respect to the setting of the numerical digit portion of its cross-bar register.
  • the circuit over which these impulses are transmitted extends from the terminating sender 500 over the tip and ring fundamental circuit conductors extending over contacts of switches 204, 205, 209, 2I0, 2li, 2I2, 404 and 405, the tip conductor 220 of fundamental circuit at the originating sender 300 being looped to the ring conductor 22
  • Stepping relay 3II operates in response to each impulse transmitted in each series of revertive impulses.
  • relay 303 is operated and therefore when the terminating sender 500 transmits the incoming group series of impulses to satisfy the incoming group setting of the register of sender 300 as determined jointly by the thousands and hundreds digits registered on the thousands vertical 303 and the hundreds vertical 304 of the register, the fundamental circuit will be opened by the operation of relay 3I2 after from one to four impulses have been received and counted by the counting relays of the sender.
  • Relay 3I3 operates and locks in series with counting relays SI2 and 3I4 and over its own front contact to ground at the right front contact of relay 308, but relays 3I2 and 3I4 do not operate in this locking circuit since their windings are shunted so long as stepping relay 3II remains operated.
  • Relay 3I2 upon operating opens the fundamental circuit to terminate the impulse aneraro series and prepares the circuits ofthe sender 300 for controlling the setting of the register of the terminating sender in accordance with the setting of its register for iinal brush selection.
  • the terminating sender 500 Since the originating sender was satisfied after the receipt of one revertive impulse in the incoming group series, the terminating sender 500 has functioned to close cross-point contacts 5I3 of the incoming group vertical of its cross-bar register in the manner fully set forth in the patent to Carpenter above referrc, to.
  • route relay 334 would have been operated in accordance with the oiiice code digits dialed. In this case, relay 305 would not be operated and assuming that the numerical digits dialed were the same as dialed to reach the subscribers line 930, cross-point contacts 3I6 of the thousands vertical 303 and cross-point contacts 3 I 1 of the hundreds vertical would be closed.
  • the terminating sender 500 transmits revertive impulses to cause the selection of a set of cross-point contacts in its incoming group vertical, as determined by the joint closure of cross-point contacts 3I3 and 3I1 of the originating sender, relay 3H upon operating in response to the first impulse closes a circuit from ground at the upper back contact of relay 320, contacts of relay 3H, lower back contact of relay 320, front contact of relay 32
  • Relay 332 operates and locks through the winding of counting relay 333 and over its own front contact to ground at the front contact of relay 308, but relay 333 does not operate in this locking circuit since its winding is shunted so long as relay 3II remains operated. As soon as the first revertive impulse ceases, relay 3I I releases and counting relay 333 thereupon operates.
  • the terminating sender 500 Since the sender 300 was satised after the receipt of six revertive impulses in the incoming group series, the terminating sender 500 has functioned to close the cross-point contacts
  • relay 509 If, as assumed, both oiiice units are reached over a common group of trunks and relay 509 has been operated as previously described, then if the cross-point contacts 5
  • a plurality of other control circuits are established over which the digits of the registered wanted line designation are transferred from the sender to the marker and recorded on groups of register relays represented by thousands relay 605, hundreds relay 606, tens relay 601, and units relay 608.
  • the hundreds relay 606 indicates Whether the hundreds digit is greater or less than 5 by operating relay 609 for digits greater than 5 and indicates the position of the digit in either series by operating one of ilve relays such as relay 6
  • the thousands relay 605 marks one of ten conductors, such as conductor 6H, which is extended to either relay 6
  • relay 601 discriminates between even and odd digits by operating relay 6
  • the units register relay 608 grounds one of ten conductors which are extended to twenty conductors according to the operated or non-operated condition of relay 6
  • 3 selects a number group frame in the ofilce unit A by completing a circuit for a marker preference relay such as or 106.
  • 5 selects a. number group frame in the oilice unit B by completing a circuit for a marker preference relay such as or 156.
  • a marker preference relay for each marker and these preference relays are arranged in a chain circuit so that only one marker can attach itself to a number group frame at a time.
  • the wanted number terminals are on number group frame 101 allocated to the oillce unit A and that preference relay 105 is operated as soon as-the frame is idle, in turn operating a multicontact relay 108 which closes the necessary circuits between the marker and the number group frame.
  • relay 108 operated, the hundred block relay 109 is operated under the control of relays 6
  • relay 109 With relay 109 operated, twenty block relay 1
  • I is connected over front contacts of relays 1
  • 4 is similarly connected over a back contact of relay 620 to the winding of busy test relay 622.
  • the corresponding terminals on the other eighteen sets are also connected to intermediate relays in the set of twenty busy test relays.
  • 5 are connected to armatures of selecting relays 6
  • each choice includes four frames with ten levels on each frame, a set of twenty double wound relays 802 to 805 is provided each pair of relays 802 and 803 or 804 and 805 representing one of the ten levels and each relay representing a pair of frames, the two windings of each relay distinguishing between frames of the pair.
  • , etc. have three windings each and are energized over the different windings in accordance with the type of service to which the line is entitled. Therefore, there is a maximum of thirty conductors leading from the line choice relays and a maximum of forty conductors outgoing from the frame or level relays. These conductors are extended in multiple to all of the number frame connector relays such as 108, 13
  • the operating conductors 806, 801 and 608 for relay 800 extend to terminal strips 1
  • the subscribers line 930 oi' oiiice unit A where it enters the oiilce is connected to a distributing frame 903 from which the line is extended to one of the primary line switches 90
  • the line itself is connected to the line terminals 904 and 905 while individual to the line terminals 904 and 905 are the sleeve or busy terminal 906 and the message register terminal 901.
  • will be cross-connected over jumper 124 to terminal 905 individual to the position in the primary switch 90
  • line 930 appears in the No. 0 level of the No. 0 frame in the No. 0 choice and is an individual message rate line. Therefore, terminal 1
  • the sleeve test circuit for line 930 extends from battery through the winding of relay 62
  • relay 623 does not operate. After an interval to permit the busy test relays 62
  • Conductor 621 extends to terminal 1
  • Relay 802 upon operating identies the No. 0 level and extends its operating ground over its inner left contact to the winding of relay 8
  • the No. 0 line choice is selected by operating the marker preference relay 908 individual to the marker shown in the No. 0 line choice connector.
  • the marker preference relay operates the multicontact relay 909 which extends all of the control circuits from the marker through to the choice.
  • 4 closes a circuit from ground through the winding of relay 8
  • 8 operates if the frame equipment is idle and connects ground to the outer left contacts of the level relays 802, 804, etc., and since relay 602 is assumed to be operated, operates horizontal level relay 9
  • connects the operating circuits for the ten select magnets, corresponding to the ten line junctors which serve the wanted line, through to the marker where one will be selected as described in detail in the Patent No. 2,232,371, granted Feb. 18, 1941 to J. W. Dehn et al.
  • 2 of this line is operated over the front contact of relay 6
  • terminal 162 is connected to an armature oi selecting relay 6
  • will be cross-connected over jumper 114 to terminal 956 individual to the position in the primary switch 95
  • line 980 ap pears in the No. 0 level oi the No. 0 frame in the No. 9 choice and is an individual message rate line. Therefore terminal 162 is connected over jumper 115 to strip '
  • 9 over contacts of relays 158 and 160 to terminal 163, thence over jumper-116, strip 180, conductor 8
  • Relay 623 does not operate in this circuit.
  • ground is connected under the control of the units register to conductor 625, thereby operating relay 6
  • 9 operated ground is connected to conductors 626 and 621, conductor 626 extending to terminal 163, thence over jumper 116 to strip 180 and conductor 819 through the left winding of relay 80
  • over this circuit identies the No. 9 line choice.
  • extends its operating ground to the winding ofj relay 8
  • Conductor 621 extends to terminal 162, thence over jumper 115 to strip 110, thence over conductor 809, left winding of relay 802 to battery.
  • Relay 802 upon operating identifies the No. level and extends its operating ground over its inner left contact to the winding of relay 8
  • operated the No. 9 line choice is selected by operating the marker preference relay 958 individual to the marker shown in the No. 9 line choice connector.
  • the marker preference relay operates the multicontact relay 959 which extends all of the control circuits from the marker through to the choice.
  • 4 closes a circuit from ground through the winding of relay 8
  • 8 operates if the frame equipment is idle and connects ground to the outer left contacts of the level relays 802, 804, etc., and since relay 802 is assumed to be operated, operates horizontal level relay 96
  • connects the operating circuits for the select magnets, corresponding to ⁇ the ten junctors which serve the wanted line, through to the marker Where one will be selected.
  • the hold magnet 962 of line 980 is operated over the front contact of relay 6
  • relay 501 If now a call is incoming for a line in oice unit A and relay 501 is therefore operated, a circuit is established as soon as the sender 500 has been connected to the marker 600 over the marker connector 50
  • does not, however, operate and consequently relay 603 operates to cause the selection of the number groupof the office unit A as previously described.
  • extends to direct ground at the upper front contact of relay 508 and relays 60
  • trunks in which the seized trunk is located for determining in which of said other olces a call is to be terminated, and means controlled in accordance with the numerical registrations established in said latter sender and the operated one of said relays for operating said latter switching mechanism to complete a connection to a wanted line terminating in any of said other oices.
  • a telephone exchange system 'a first oiice, other offices, a common group of trunks extending from said rst olce to said other oilices.
  • switching mechanism in said first office a sender in said first oiilce having registers i'or registering the oiiice code and numerical designations of wanted lines, means controlled in accordance with the oilice code registrations for setting said switching mechanism to extend a connection to an idle trunk of said group, switching mechanism in said other ofiices.
  • a sender common to said other otiices having registers for registering the numerical designations of wanted lines in accordance with the setting of the numerical registers of said ilrst sender, means controlled in accordance with the omce code registrations of said first sender for establishing a discriminating setting of one of the registers of said latter sender for determining in which of said other oillces a call is to be terminated, and means controlled in accordance with the numerical registrations established in said latter 'sender and the discriminating setting of said one register for operating said latter switching mechanism to complete a connection to a wanted line in any of said other ofilces.
  • sender common to said second and third oilcesl having registers, means for transmitting series of revertive impulses from said latter sender to said iirst sender whereby the registers of said latter sender are set to register the numerical designations of wanted lines in accordance with the setting of the numerical registers of said first sender, means in said first sender operable in accordance with the oiiice code registrations of said third oilce to cause the addition of five impulses to one of said series of revertive impulses to establish a discriminatory setting of one of the registers of said latter sender for determining that a call is to be terminated in said third ofce, and means controlled in accordance with the numerical registrations established in said latter sender and the discriminating setting of said one register for operating said latter switching mechanism to complete a connection to a wanted line in either said second or third office.
  • transfer means in said marked selectably controlled in accordance with the discriminating setting of said one register for determining to which of said other oiiices said marker shall direct a call and means in said marker controlled in accordance with the numerical registrations established in said latter sender to complete a connection to a wanted line terminating in the oilce determined by said transfer means.
  • a rst oitlce other oilices.
  • switching mechanism ln said first oiiice for extending connections to said other oices.
  • a sender in said rst omce having registers for registering the oiiice code and numerical designations oi.' wanted lines, means controlled in accordance with the oiiice code resistrations for setting said switching mechanism to extend a connection to said other oiiices, switching mechanism in said other oflices common thereto, a sender common to said'other oiiices having registers for registering the nu.
  • discriminating means in said latter sender operable in accordance with the ofiice code designations registered in said mst sender for determining in which of said other oiilces a call is to be terminated, and means common to said other oiiices controlled in accordance with the numerical registrations established in said latter sender and said discriminating means for operating said common switching mechanism to complete a connection to a wanted line in any of said other offices.
  • a rst ofnce, other ofces. groups oi inter oiiice trunks extending from said first office to said other oces,l switching mechanism in said rst oiiice, a sender in said ilrst oiiice having registers for registering the ofiice code and numerical designations of wanted lines.
  • means controlled in accordance with the oflce code registration for setting said switching mechanism to extend a connection to an idle trunk in any of said groups of trunks, switching mechanism in said other oiilces common thereto.
  • a sender common to said other oiilces having registers for registering the numerical designations of wanted lines in accordance with the setting of the numerical registers of said rst sender.
  • discriminating-means in said latter sender operable in accordance with the group ot trunks in which the seized trunk is located for determining in which of said other oinces the call is to be terminated, and means controlled in accordance with the numerical registrations established in said latter sender and said discriminating means for operating said common switching mechanism to complete a connection to a wanted line terminating in any of said other oilices.
  • a nrst oiiice, other ofiices means for establishing a connection from said first oiiice to said other oilices, a plurality of subscribers lines terminat-4 lng in each oi.' said other cnices.

Landscapes

  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Sub-Exchange Stations And Push- Button Telephones (AREA)
  • Relay Circuits (AREA)
US335241A 1940-05-15 1940-05-15 Telephone system Expired - Lifetime US2261370A (en)

Priority Applications (4)

Application Number Priority Date Filing Date Title
BE483523D BE483523A (en(2012)) 1940-05-15
FR961957D FR961957A (en(2012)) 1940-05-15
US335240A US2259101A (en) 1940-05-15 1940-05-15 Telephone system
US335241A US2261370A (en) 1940-05-15 1940-05-15 Telephone system

Applications Claiming Priority (3)

Application Number Priority Date Filing Date Title
US335240A US2259101A (en) 1940-05-15 1940-05-15 Telephone system
US335241A US2261370A (en) 1940-05-15 1940-05-15 Telephone system
US335245A US2259100A (en) 1940-05-15 1940-05-15 Operator's position circuit

Publications (1)

Publication Number Publication Date
US2261370A true US2261370A (en) 1941-11-04

Family

ID=27407045

Family Applications (2)

Application Number Title Priority Date Filing Date
US335241A Expired - Lifetime US2261370A (en) 1940-05-15 1940-05-15 Telephone system
US335240A Expired - Lifetime US2259101A (en) 1940-05-15 1940-05-15 Telephone system

Family Applications After (1)

Application Number Title Priority Date Filing Date
US335240A Expired - Lifetime US2259101A (en) 1940-05-15 1940-05-15 Telephone system

Country Status (3)

Country Link
US (2) US2261370A (en(2012))
BE (1) BE483523A (en(2012))
FR (1) FR961957A (en(2012))

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2468299A (en) * 1945-07-07 1949-04-26 Bell Telephone Labor Inc Supervisory signaling in telephone or like switching systems
US2573569A (en) * 1948-10-29 1951-10-30 Bell Telephone Labor Inc Frame and trunk selection
US2618708A (en) * 1942-08-06 1952-11-18 Automatic Elect Lab Telephone system with main and secondary register
US2747021A (en) * 1950-09-21 1956-05-22 Gen Electric Co Ltd Telecommunication systems embodying automatic exchanges
US2750448A (en) * 1950-05-31 1956-06-12 Mercer Richard Telecommunication systems
US2761901A (en) * 1946-01-26 1956-09-04 Telefonaktiebolaget L M Eriess Device for setting of selectors by means of audio-frequencies
US2885481A (en) * 1955-05-23 1959-05-05 Gen Telephone Lab Inc Multi-office telephone system
US2981803A (en) * 1955-12-28 1961-04-25 Bell Telephone Labor Inc Program switching system
US3231684A (en) * 1960-04-04 1966-01-25 Ericsson Telefon Ab L M Control register for a multi-exchange telephone system

Families Citing this family (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
NL61666C (en(2012)) * 1944-05-17 1948-09-15 Ericsson Telefon Ab L M
US2534822A (en) * 1944-11-17 1950-12-19 Ericsson Telefon Ab L M Connecting device for telephone exchanges using a register

Cited By (9)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2618708A (en) * 1942-08-06 1952-11-18 Automatic Elect Lab Telephone system with main and secondary register
US2468299A (en) * 1945-07-07 1949-04-26 Bell Telephone Labor Inc Supervisory signaling in telephone or like switching systems
US2761901A (en) * 1946-01-26 1956-09-04 Telefonaktiebolaget L M Eriess Device for setting of selectors by means of audio-frequencies
US2573569A (en) * 1948-10-29 1951-10-30 Bell Telephone Labor Inc Frame and trunk selection
US2750448A (en) * 1950-05-31 1956-06-12 Mercer Richard Telecommunication systems
US2747021A (en) * 1950-09-21 1956-05-22 Gen Electric Co Ltd Telecommunication systems embodying automatic exchanges
US2885481A (en) * 1955-05-23 1959-05-05 Gen Telephone Lab Inc Multi-office telephone system
US2981803A (en) * 1955-12-28 1961-04-25 Bell Telephone Labor Inc Program switching system
US3231684A (en) * 1960-04-04 1966-01-25 Ericsson Telefon Ab L M Control register for a multi-exchange telephone system

Also Published As

Publication number Publication date
US2259101A (en) 1941-10-14
FR961957A (en(2012)) 1950-05-26
BE483523A (en(2012))

Similar Documents

Publication Publication Date Title
US2261370A (en) Telephone system
US2421919A (en) Telephone routing system
US2558571A (en) Operator controlled coin collecting and refunding means for dial telephone systems
US2335481A (en) Telephone system
US2299212A (en) Telephone system
US2208765A (en) Telephone system
US2301015A (en) Telephone system
US2262595A (en) Telephone system
US2338752A (en) Telephone system
US2039668A (en) Telephone system
US2092465A (en) Telephone system
US1970337A (en) Telephone system
US1530968A (en) Recording device
US1577033A (en) Automatic telephone-exchange system
US1916760A (en) Telephone exchange system
US2686223A (en) Combined toll and local connector
US2468305A (en) Signaling system
US2022030A (en) Signaling system
US2367635A (en) Telephone system
US2285908A (en) Sender control system
US2268635A (en) Telephone system
US2214809A (en) Telephone system
US1968420A (en) Telephone system
US1862536A (en) Tandem trunk circuits
US2105898A (en) Telephone exchange system