US1728348A - Selector switch - Google Patents

Selector switch Download PDF

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US1728348A
US1728348A US243126A US24312627A US1728348A US 1728348 A US1728348 A US 1728348A US 243126 A US243126 A US 243126A US 24312627 A US24312627 A US 24312627A US 1728348 A US1728348 A US 1728348A
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Prior art keywords
shaft
contact
switching
sleeve
selector
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US243126A
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Lienzen David Laurentius
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Telefonaktiebolaget LM Ericsson AB
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Telefonaktiebolaget LM Ericsson AB
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H67/00Electrically-operated selector switches
    • H01H67/02Multi-position wiper switches
    • H01H67/04Multi-position wiper switches having wipers movable only in one direction for purpose of selection
    • H01H67/12Linear-motion switches

Definitions

  • the invention relates to selectors of the kind used in the automatic telephony and in which the fixed contacts form a single row of contacts or sets of contacts. More particularly the invention relates to switches of the kind in which the selector mechanism comprises a number of switching members each being adapted to select the different lines of a corresponding group of lines, and in which said switching members are arranged to be set in position by means of a common setting mechanism and adapted to be selected and made operative by means of a group selecting mechanism. Selectors of this kind are known in which said switching members consist of a number of contact arms which are set all at a time after one of them has been selected and connected up to the incoming line.
  • This arrangement has the disadvantage that all switching members must be set together though only one of them need to be taken into use for each connection.
  • the present invention removes said disadvantage by said switching members being arranged to be coupled mechanically in and out of connection with the setting mechanism by means of the group selecting mechanism so that in selecting a line in a certain group only that switching member is moved which corresponds to such a group.
  • Figure 3 is a horizontal section on the line 33 in Figure 1.
  • Figures i, 5 and 6 show similar views of another construction.
  • Figure 7 shows a detail.
  • Figures 8 and 9 are a side view and a plan View respectively of a modification adapted for selectors having searching movement.
  • the wires of the contact field as well as the selector mechanisms are mounted in a frame work consisting of a number of certical beams 1 which are joined together at their upper and lower ends by means of horizontal bars 2, 3. Between the two beams of each pair there is provided a number of for instance ten or fifteen identical selector mechanisms with appertaining contact fields.
  • the latter consist in the example shown of ten parallel pipedical bundles of horizontal wires 4 preferably bare wires, disposed above one another, and a number of bundles of wires 5, corresponding to the different selector mechanisms and extending vertically.
  • the wires 4 may for instance constitute the outgoing lines, whereas the incoming lines are represented by the vertical wires 5.
  • the wire field is carried by a frame work arranged between the horizontal bars and consisting of two vertical bars 6, 7 and a number of horizontal bars 8 of an angular cross-section which are screwed to the bars 6, 7, and further a number of vertical bars 9 which are screwed to the horizontal bars 2, 8.
  • the wires 4 are drawn through holes in insulating plates 10 which are screwed to the bars 9.
  • Each plate 10 carries a bundle of wires comprising ten lines each consisting of three wires, viz, the two speaking line branches and a test wire. The three wires of each line form a horizontal layer of wires.
  • Each set of three contact arms is arranged to be operated from the selector mechanism through the medium of a thin plate 13 of insulating material placed on the contact arms and adapted to be retained in position by the wires passing through holes in the plate. Said plate is normally kept in a raised horizontal position by the contact arms 12. Inserted in the front edge of said plate there is a piece of metal 14 serving an actuating point for the selector mechanism as will be described hereinafter.
  • the selector mechanism comprises a number of switching members 15.
  • switching members 15 In the example shown there are ten such members, which consist of sleeves thrust on a vertical shaft 16 and provided with contact actuating members consisting of radial pins 17 arranged along a helical line. By rotating the sleeve said pins can. be brought sue-cos sively in operating position to actuate the metal pieces 14: on the plates 13, so that the different groups of contact springs 1.2 are successively brought in contact with the ap pertaining wires 1.
  • the sleeves are mounted in journals 18 secured to the left hand side of a plate 19, which forms the frame in which the selector mechanism is mounted.
  • each selector mechanism is assumed to establish connection between one incoming line and one hundred outgoing lines, the latter being arranged in ten groups each containing ten lines.
  • each line group has allotted to it a separate switching sleeve 15.
  • the switching sleeves 15 are arranged to be coupled mechanically in and out of connection with the shaft 16 by a vertical movement of the latter.
  • the coupling' is effected by means of pins 20 provided on the shaft, said pins being adapted, upon the shaft being raised, to enter notches 21 in rings 22 which are fastened inside the sleeves to their upper ends.
  • the selecting of the different switching sleeves is effected by means of a step-wise vertical movement of the shaft 16 from its normal position.
  • the first group of contact arms is released and is caused by, the elasticity of the contact arms to resume its normal position, the second group of contact arms being instead actuated by the second pin 17 011 the sleeve 15.
  • any wanted group of'contact arms may be selected and operated.
  • the switching sleeves 15 of all the other line groups are ino iierative, as the appertaining coupling pins 20 are not then in engagement with the corresponding sleeves. If the shaft 16 is at first raised two steps, the second switching sleeve 15 will be coupled to the shaft 16 by the appertaining pin 20 entering into engagement with the notch 21 of the second sleeve.
  • the coupling pin 20 of first switching sleeve will then be located above this sleeve and the following rotation of the shaft 16 will therefore only cause the second switching sleeve to be rotated.
  • the third, fourth etc. switching sleeves can be coupled to the shaft 16 by lifting the shaft three, four etc. steps. After the end of the conversation the shaft 16 and the sleeve 15 are restored to normal position by a further rotation of the shaft 16 in the same direction, until it reaches its normal position, in which the pins 20 are all right below the notches 21 of the appertaining sleeves.
  • the motion mechanism consists of a lifting electro-n'iagnet 23 and a rotary magnet 24 with appertaining driving pawls 25 and 26 respectively operating on teeth 27 and 28 respectively on the lower end of the shaft 16.
  • the magnets 23, 24 and 30 are mounted together with the shaft 16 and the appertaining switching sleeves 15 on the left hand side of the appertaining frame 19, which thus carries the whole selector mechanism.
  • the frame 19 is secured to the tranvcrsal bars 2, 3 by means of screws 41, 42 in such a manner that it can be easily detached by loosening said screws.
  • the mounting of the frame in its position is facilitated by its lowermost edge being guided in a slot provided in a base plate 34 screwed to the lower bar 3.
  • a transversal bar 35 serves as a support for the frame while being inserted in its place.
  • the setting movements of the selectors may also be continuous in which case the shaft 16 is arranged to be driven from rotating shafts or the like according to methods well known in the automatic telephony.
  • the group selecting mechanism consists of a vertical shaft 36 disposed in front of the shaft 16 and adapted to be ro tated by means of an electro-magnet 37.
  • the shaft 16 need not be displaced vertically only a rotary movement being required.
  • the coupling of the shaft 16 with the different switching sleeves 15 is effected in. this case by means of radial pins 38 provided on the shaft 86 and arranged to operate couplings provided at the upper ends of the sleeves.
  • Said couplings consist chiefly of a disk 39 secured to the shaft 16 and a spring 40 which is connected with the sleeve and which carries at its free end a vertical pin 41.
  • Figures 8 and 9 show a modification adapted to make the selector capable of operating as a searcher for a large number of lines.
  • the selector difiers'from that of Figures 4 to 7 chiefly only by the electro-magnet 37 and the appertaining stepping mechanism being dispensed with and replaced by a gearing 46 by which the shafts 16 and 36 are coupled together so as to cause the shaft 36 to be rotated one step for each full revolution of the shaft 16.
  • a disk 46 is secured to the shaft 16 and provided with a pin 47 which engages the teeth of a gear wheel 45 provided on the shaft 36.
  • the lowermost switching sleeve 15 When the shaft 16 is rotated from its normal position by means of the electro-magnet 24, the lowermost switching sleeve 15 will first be coupled to the shaft 16 and rotated for one revolution, the different sets of contacts being then actuated and the lines tested in succession. In case all lines of the first group should be engaged the electro-magnet 24 will continue to operate and the second switching sleeve 15 will be coupled to the shaft 16 and moved to search for a disengaged line in the second group and so on.
  • a selector can be constructed for 100 or more lines.
  • a selector switch having groups of fixed contacts disposed in a rectilinear row and a corresponding number of switching members movable in front of the appertaining contact groups and arranged to be selected by means of a group selecting mechanism and to be set in position separately by means of a common set-ting mechanism, said switching members being rotatable about an axis parallel with the contact row and provided with a number of contact operating members disposed around the switching member and adapted to be brought successively in operative position by the rotation of the switching member.
  • a selector switch the combination of a number of groups of fixed contacts disposed in a rectilinear row, a corresponding number of switching sleeves rotatable in front of the appertaining contact groups, and thrust on a common driving shaft parallel with the contact row, a group selecting mechanism for selecting one of said sleeves, a common setting mechanism for setting any sleeve selected in position, and contact operating members provided on the sleeves and adapted to be brought successively in operative position by the rotation of the sleeve.
  • a selector switch as claimed in claim 2 in which the common driving shaft is arranged horizontally.
  • a selector switch as claimed in claim 2 in which the sleeves are arranged to be selected and made operative by means of a separate group selecting shaft parallel with the driving shaft.
  • a selector switch the combination of a number of groups of fixed contacts disposed in a rectilinear row, a corresponding number of switching sleeves rotatable in front of the appertaining contact groups and thrust on a common driving shaft parallel with the contact row, a group selecting mechanism for selecting one of said sleeves comprising a rotatable shaft parallel with said driving shaft, a common setting mechanism for setting any sleeve selected in position, and means provided on the sleeves for selecting the individual contacts of each group by rotating the sleeve.
  • a selector switch comprising a multiple contact field having incoming and outgoing lines extending perpendicularly to each other through the contact field and sets of contacts at the points of intersection for interconnecting the incoming and outgoing lines, a number of switching members each capable of selecting and operating the sets of contacts of a plurality of lines, and means for setting each switching member in as many positions as there are lines to be selected by said member.
  • a selector switch comprising a multiple contact field having incoming and outgoing lines extending perpendicularly to each other through the contact field and sets of contacts at the points of intersection for interconnecting the incoming and outgoing lines, a number of rotatable switching members each capable of selecting a. plurality of lines and provided with contact opcrating members for mechanically actuating a number of sets of contacts in succession, and means for set-ting each switching member in operative positions.

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  • Structure Of Telephone Exchanges (AREA)

Description

e Sheets-Sheet Filed Dec. 28. 1927 //v VENTO p 1929- D. L. LiENZEN 1,728,348
SELECTOR SWITQH Filed Dec. 28, 1927 6 Sheets-Sheet 2 Sept. 17, 1929.
D. L. LIENZEN SELECTOR SWITCH Filed De c. 28 1927 6 Sheets-Sheet Sept. 17, 1929. D. L. LIENZEN 2,728,348
SELECTOR SWITCH Filed Dec. 28, 1927 6 Sheets-Sheet 5/: WWW
1927 6 Sheets-Sheet 5 D. L. LIENZEN SELECTOR SWITCH Sept. 1 7, 1929.
Filed Dec. 28
Sept. 17, 1929. D. LIENZEN SELECTOR SWITCH Filed Dec. 28, 1927 6 Sheets-Sheet patented Sept. 17, 1929 1 1' UNITED STATES PATENT OFFICE DAVID LAURENTIUS LIENZEN, OF STOCKHO'LM, SWEDEN, ASSIGNOR TO TELEFON- AKTIEBOLAGET L. M..ERICSSO1 I, 0F STGCKHOLIVI, SWEDEN, A COMPANY OF SWEDEN SELECTOR SWITCH Application filed December 28, 1927, Serial No. 243,126, and in Sweden January 5, 1927.
The invention relates to selectors of the kind used in the automatic telephony and in which the fixed contacts form a single row of contacts or sets of contacts. More particularly the invention relates to switches of the kind in which the selector mechanism comprises a number of switching members each being adapted to select the different lines of a corresponding group of lines, and in which said switching members are arranged to be set in position by means of a common setting mechanism and adapted to be selected and made operative by means of a group selecting mechanism. Selectors of this kind are known in which said switching members consist of a number of contact arms which are set all at a time after one of them has been selected and connected up to the incoming line. This arrangement has the disadvantage that all switching members must be set together though only one of them need to be taken into use for each connection. -The present invention removes said disadvantage by said switching members being arranged to be coupled mechanically in and out of connection with the setting mechanism by means of the group selecting mechanism so that in selecting a line in a certain group only that switching member is moved which corresponds to such a group.
The invention will be more closely described with reference to the accompanying drawings, which show the invention applied to selectors of the kind in which the illcoming and outgoing lines extend in transverse directions through the contact field and are connected in the points of intersection to contacts which can be selected and operated by means of a selector mechanism provided in front of the contact field. A characteristic feature of such selectors is that they have no movable contact arms the selector mechanism being consequently entirely mechanical. The invention is, however, not limited to such selectors as it may be applied with advantage also to selectors having displaceable contact arms. Figures 1 to 3 show a group of selectors with the appertaining contact field. Figure 1 is a sectional view on the line 11 of Figure 2. Figure 2 is a front view of the selectors and the contact field. Figure 3 is a horizontal section on the line 33 in Figure 1. Figures i, 5 and 6 show similar views of another construction. Figure 7 shows a detail. Figures 8 and 9 are a side view and a plan View respectively of a modification adapted for selectors having searching movement.
in the construction shown in Figures 1 to S the wires of the contact field as well as the selector mechanisms are mounted in a frame work consisting of a number of certical beams 1 which are joined together at their upper and lower ends by means of horizontal bars 2, 3. Between the two beams of each pair there is provided a number of for instance ten or fifteen identical selector mechanisms with appertaining contact fields. The latter consist in the example shown of ten parallel pipedical bundles of horizontal wires 4 preferably bare wires, disposed above one another, and a number of bundles of wires 5, corresponding to the different selector mechanisms and extending vertically. The wires 4 may for instance constitute the outgoing lines, whereas the incoming lines are represented by the vertical wires 5. The wire field is carried by a frame work arranged between the horizontal bars and consisting of two vertical bars 6, 7 and a number of horizontal bars 8 of an angular cross-section which are screwed to the bars 6, 7, and further a number of vertical bars 9 which are screwed to the horizontal bars 2, 8. The wires 4 are drawn through holes in insulating plates 10 which are screwed to the bars 9. Each plate 10 carries a bundle of wires comprising ten lines each consisting of three wires, viz, the two speaking line branches and a test wire. The three wires of each line form a horizontal layer of wires.
of contact arms 12 arranged at the points of intersection of the different lines and which consist of elastic metal strips which are soldered or otherwise connected to the wires 5. They are arranged so as to extend horizontally between the horizontal layers of wires 1, so that the ends of the contact arms will be located right above the corresponding Wires 4.-. Each set of three contact arms is arranged to be operated from the selector mechanism through the medium of a thin plate 13 of insulating material placed on the contact arms and adapted to be retained in position by the wires passing through holes in the plate. Said plate is normally kept in a raised horizontal position by the contact arms 12. Inserted in the front edge of said plate there is a piece of metal 14 serving an actuating point for the selector mechanism as will be described hereinafter.
The selector mechanism comprises a number of switching members 15. In the example shown there are ten such members, which consist of sleeves thrust on a vertical shaft 16 and provided with contact actuating members consisting of radial pins 17 arranged along a helical line. By rotating the sleeve said pins can. be brought sue-cos sively in operating position to actuate the metal pieces 14: on the plates 13, so that the different groups of contact springs 1.2 are successively brought in contact with the ap pertaining wires 1. The sleeves are mounted in journals 18 secured to the left hand side of a plate 19, which forms the frame in which the selector mechanism is mounted. In the example shown each selector mechanism is assumed to establish connection between one incoming line and one hundred outgoing lines, the latter being arranged in ten groups each containing ten lines. Thus, each line group has allotted to it a separate switching sleeve 15. In order to be able to establish connection in any line group wanted, the switching sleeves 15 are arranged to be coupled mechanically in and out of connection with the shaft 16 by a vertical movement of the latter. The coupling'is effected by means of pins 20 provided on the shaft, said pins being adapted, upon the shaft being raised, to enter notches 21 in rings 22 which are fastened inside the sleeves to their upper ends. The selecting of the different switching sleeves is effected by means of a step-wise vertical movement of the shaft 16 from its normal position. By raising the shaft one step the first i. e. the lowermost sleeve 15 is coupled to the shaft 16 by the lowermost pin 20 entering the notch 21 in said sleeve. If connection is wanted with a line in the first group, the shaft 16 is then rotated stepwise the sleeve 15 being carried round by the pin 20. The lowermost pinl? on said sleeve will then press against the metal piece 14 of the lowermost plate .13, which therefore will press the appertaining group of contact arms 12 into contact with the corresponding wires 4. Figures 1 and 3 show the position of the mechanism after the sleeve 15 has thus been rotated for one step in the direction of the arrow shown in Figure 3. If the shaft 16 is rotated for another step, the first group of contact arms is released and is caused by, the elasticity of the contact arms to resume its normal position, the second group of contact arms being instead actuated by the second pin 17 011 the sleeve 15. In this way evidently any wanted group of'contact arms may be selected and operated. During the switching operation in one line group the switching sleeves 15 of all the other line groups are ino iierative, as the appertaining coupling pins 20 are not then in engagement with the corresponding sleeves. If the shaft 16 is at first raised two steps, the second switching sleeve 15 will be coupled to the shaft 16 by the appertaining pin 20 entering into engagement with the notch 21 of the second sleeve. The coupling pin 20 of first switching sleeve will then be located above this sleeve and the following rotation of the shaft 16 will therefore only cause the second switching sleeve to be rotated. Simi larly the third, fourth etc. switching sleeves can be coupled to the shaft 16 by lifting the shaft three, four etc. steps. After the end of the conversation the shaft 16 and the sleeve 15 are restored to normal position by a further rotation of the shaft 16 in the same direction, until it reaches its normal position, in which the pins 20 are all right below the notches 21 of the appertaining sleeves.
The motion mechanism consists of a lifting electro-n'iagnet 23 and a rotary magnet 24 with appertaining driving pawls 25 and 26 respectively operating on teeth 27 and 28 respectively on the lower end of the shaft 16. During the operation of the electromagnet 23 the shaft is maintained in a raised position of the pawl 29, which together with the pawl 25 may be brought out of engagement with the teeth 27 by means of a restoring electro-magnet 30. The magnets 23, 24 and 30 are mounted together with the shaft 16 and the appertaining switching sleeves 15 on the left hand side of the appertaining frame 19, which thus carries the whole selector mechanism. The frame 19 is secured to the tranvcrsal bars 2, 3 by means of screws 41, 42 in such a manner that it can be easily detached by loosening said screws. The mounting of the frame in its position is facilitated by its lowermost edge being guided in a slot provided in a base plate 34 screwed to the lower bar 3. A transversal bar 35 serves as a support for the frame while being inserted in its place.
The setting movements of the selectors may also be continuous in which case the shaft 16 is arranged to be driven from rotating shafts or the like according to methods well known in the automatic telephony.
In the construction shown in the Figures 4, 5, 6 and 7 the group selecting mechanism consists of a vertical shaft 36 disposed in front of the shaft 16 and adapted to be ro tated by means of an electro-magnet 37. In this case the shaft 16 need not be displaced vertically only a rotary movement being required. The coupling of the shaft 16 with the different switching sleeves 15 is effected in. this case by means of radial pins 38 provided on the shaft 86 and arranged to operate couplings provided at the upper ends of the sleeves. Said couplings consist chiefly of a disk 39 secured to the shaft 16 and a spring 40 which is connected with the sleeve and which carries at its free end a vertical pin 41. The pin last mentioned is located normally, see Figure 7 opposite to a notch 42 in the ring 39. Upon a pin 38 coming into contact wth the spring 40 during the rotation of the shaft 36, the pin 41 is pressed into the recess 42, whereby the appertaining sleeve 15 is coupled to the shaft 16 so as to be rotated together with the shaft 17 when the latter is rotated. During the rotary movement the pin 41 is kept in engagement with the ring 39 by means of a ring 43 secured to the frame and provided with an opening 44 in which the pin 41 is located normally. By this arrangement any wanted switching sleeve may be selected and coupled with the shaft 16 only by a rotary movement of the shaft 36. The restoring of the selector is effected by rotating the shafts 16, 36 in the same direction back into the normal position. For the rest the construction of the selector mechanism and the contact field is the same as in Figures 1 to 3.
Figures 8 and 9 show a modification adapted to make the selector capable of operating as a searcher for a large number of lines. The selector difiers'from that of Figures 4 to 7 chiefly only by the electro-magnet 37 and the appertaining stepping mechanism being dispensed with and replaced by a gearing 46 by which the shafts 16 and 36 are coupled together so as to cause the shaft 36 to be rotated one step for each full revolution of the shaft 16. In the example shown a disk 46 is secured to the shaft 16 and provided with a pin 47 which engages the teeth of a gear wheel 45 provided on the shaft 36.
When the shaft 16 is rotated from its normal position by means of the electro-magnet 24, the lowermost switching sleeve 15 will first be coupled to the shaft 16 and rotated for one revolution, the different sets of contacts being then actuated and the lines tested in succession. In case all lines of the first group should be engaged the electro-magnet 24 will continue to operate and the second switching sleeve 15 will be coupled to the shaft 16 and moved to search for a disengaged line in the second group and so on. Such a selector can be constructed for 100 or more lines.
I claim: r
1. A selector switch having groups of fixed contacts disposed in a rectilinear row and a corresponding number of switching members movable in front of the appertaining contact groups and arranged to be selected by means of a group selecting mechanism and to be set in position separately by means of a common set-ting mechanism, said switching members being rotatable about an axis parallel with the contact row and provided with a number of contact operating members disposed around the switching member and adapted to be brought successively in operative position by the rotation of the switching member.
2. In a selector switch the combination of a number of groups of fixed contacts disposed in a rectilinear row, a corresponding number of switching sleeves rotatable in front of the appertaining contact groups, and thrust on a common driving shaft parallel with the contact row, a group selecting mechanism for selecting one of said sleeves, a common setting mechanism for setting any sleeve selected in position, and contact operating members provided on the sleeves and adapted to be brought successively in operative position by the rotation of the sleeve.
3. A selector switch as claimed in claim 2 in which the common driving shaft is arranged horizontally.
4. A selector switch as claimed in claim 2 in which the sleeves are arranged to be selected and made operative by means of a separate group selecting shaft parallel with the driving shaft.
5. In a selector switch the combination of a number of groups of fixed contacts disposed in a rectilinear row, a corresponding number of switching sleeves rotatable in front of the appertaining contact groups and thrust on a common driving shaft parallel with the contact row, a group selecting mechanism for selecting one of said sleeves comprising a rotatable shaft parallel with said driving shaft, a common setting mechanism for setting any sleeve selected in position, and means provided on the sleeves for selecting the individual contacts of each group by rotating the sleeve.
6. A selector switch comprising a multiple contact field having incoming and outgoing lines extending perpendicularly to each other through the contact field and sets of contacts at the points of intersection for interconnecting the incoming and outgoing lines, a number of switching members each capable of selecting and operating the sets of contacts of a plurality of lines, and means for setting each switching member in as many positions as there are lines to be selected by said member.
7. A selector switch comprising a multiple contact field having incoming and outgoing lines extending perpendicularly to each other through the contact field and sets of contacts at the points of intersection for interconnecting the incoming and outgoing lines, a number of rotatable switching members each capable of selecting a. plurality of lines and provided with contact opcrating members for mechanically actuating a number of sets of contacts in succession, and means for set-ting each switching member in operative positions.
In testimony whereof I aifix my signature.
DAVID LAURENTIUS LIENZEN.
US243126A 1927-01-05 1927-12-28 Selector switch Expired - Lifetime US1728348A (en)

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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2542283A (en) * 1947-03-05 1951-02-20 Automatic Elect Lab Telephone system

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US2542283A (en) * 1947-03-05 1951-02-20 Automatic Elect Lab Telephone system

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