US1303084A - Cross-bar line-switch - Google Patents

Cross-bar line-switch Download PDF

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US1303084A
US1303084A US1303084DA US1303084A US 1303084 A US1303084 A US 1303084A US 1303084D A US1303084D A US 1303084DA US 1303084 A US1303084 A US 1303084A
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line
incoming
contacts
trunk
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    • HELECTRICITY
    • H01ELECTRIC ELEMENTS
    • H01HELECTRIC SWITCHES; RELAYS; SELECTORS; EMERGENCY PROTECTIVE DEVICES
    • H01H67/00Electrically-operated selector switches
    • H01H67/22Switches without multi-position wipers
    • H01H67/26Co-ordinate-type selector switches not having relays at cross-points but involving mechanical movement, e.g. cross-bar switch, code-bar switch

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  • This invention relates to switching mechanisms for use in telephone systems, and more particularly to switches of the cross-bar type, that is, switches in which interconnection between incoming and outgoing lines is effected by the cooperative action of a bar in one of two sets of intersecting bars with a bar in the other of such sets.
  • the principal object of this invention is to effect the interconnection of lines in a cross-bar switch by the actuation of the corresponding sets of contact terminals in response to the successive longitudinal movements of a pair of intersecting cross-bars.
  • the switch herein disclosed is adapted to be used as a line switch or trunk finder
  • Figure 1 is a perspective view of a section ofthe switch structure showing the terminal bank with its projecting spr'ingcontacts and theauxiliary crossbars for effecting an interconnection of the er, and asceispring contacts.
  • FIG. 2 is shown a. schematic representation of the operating mechanisms and the circuits of a switch embodying the features of this invention.
  • Fig. 3 is a detached view showing-a part of the operating mechanism in one stage ofits operation.
  • Means are provided-for causing a vertical movement of a line bar 6 u onthe initiation of a call over the line L,, 2 with which such bar 6 is associated. whereupon the non-conducting bars 8 are raised to place them in operative relation with lugs 10 on horizontal trunk bars 9.
  • the trunk bars 9, individual to each set of trunk multiples, are mounted in such a manner as to be capable of movement 1n a longitudinal direction.
  • the depressed lugs 10 integral with the trunk bar 9 are each associated with a bar 8, and are shaped in a manner such that, upon the horizontal movement of a trunk bar 9, a bar 8 individual to the multiples of a line L L and previously positioned by a line bar 6, will be engaged by a lug 10 on the actuated trunk bar and raised thereby to cause the engagement of the contact points 11 and 12 o t .c calling line multiple contact springs 2, 3 with the idle trunk multiples 4, 5.
  • the line L L is thereby extended to the trunk T T
  • the invention will be best understood and the features thereof best ap ear, from a description of the operation 0 a switch, of the character described, in connecting the line with an idle trunk.
  • relay 13 Upon the initiation of a call over the line L L L relay 13 is energized over a circuit extending from ground, right-hand windfront contact of relay 13, conductor 18, contacts 19, magnet 17, to ground.- The magnet 17 attracts its armature 21, and by means of a pawl 22 pivotally mounted at the extremity thereof, raises'the line bar 6.
  • all the bars 8, associated with multiples 2, 3, of the line L L are raised into a position to be engaged by the downwardly bent portion of the lugs 10 upon movement of any trunk bar 9.
  • ductor 30 magnet 29, normally closed contacts 31, conductor 32, conductors 33, 34, contacts 28, conductor 35, to ground.
  • Magnet 29 in attracting its armature 36 disengages catch 56 from a projection 37 onthe trunk bar 9.
  • the bar 9 on being released is raised an additional amount, and contactsmoved in a horizontal direction under the action of a spring 38, whereby the inclined section of the lug 10 rides under one of the previously raised bars8.
  • the bar 8 is thus points 11, 12 thereupon engage the multiple spring contacts 4, 5 of the trunk T T Simultaneously with the upward movement of the bar 6, pawl 22 causes the partial clockwise rotation of a sector 23 which is rotatably mounted on a pin 24 fixed to the frame (not shown).
  • a pawl 25 pivoted on a pin 39 thereupon drops into a recess or notch 26.
  • cont-acts 15 and 19 are opened, and contact 27 is closed, as is more clearly indicated in Fig.- 3, which shows sector 23 in rotated position.
  • the circuit for magnet 17 is opened and magnet 17 thereupon releases its armature 21.
  • Pawl 22 disengages notch 40 in sector 23, and also disengages the line bar 6v which then falls back, and allows the bars 8, associated with the remain? ing multiples of line L and L to return to their normal positions out of operative relation with the lugs 10 of any trunk bars 9 that may be subsequently operated.
  • Pawl 22 will take the position shown in Fig. 3, and will thereby place a Vertically extending projection 42, integral therewith, inoperative relation with a cup-shaped projection 43 on pawl 25.
  • relay 13 At contacts 15, the circuit for relay 13 is broken, but relay 13 will remain energized over a new circuit closed for its left-hand winding immediately upon the extension of line L L to the trunk T T through the stepping relay SR of the succeeding selector or connector switch.
  • This circuit will be as follows: grounded battery, left-hand windwill control the step-by-step operation of the particular switch to which it is individual.
  • contact 46 is not closed, however, as long as magnet 29 is energized since a hook-shaped member 70 carried by armature 36 engages a projection 71 on spring 72 and prevents the operation of these contacts.
  • the closure of contact 62 maintains magnet 29 energized over a circuit from grounded battery, conductor 30, winding of magnet 29, contact 62, conductor 63, to ground at the armature and back contact or relay RR, which is a relay at the succeeding switch next to be-operated.
  • the relay RR is preferably the first slow. relay of any well-known type of step-b3 step selector switch, and will be energized when such switch is taken for use and will remain energized until the release of the switch. After the calling line has been extended to such selector switch, the relay RR will be energized and will open the circuit of 'magnet 29. which thereupon denergizes. The retraction of the armature 36 allows contact 46 to be closed.
  • a call coming in on any line other than L L during the busy condition of the latter will cause the release of trunk bar 9 upon the closure of a set of contacts 28 associated with the line bar of such other calling line.
  • the extended starter circuit for magnet 29 will be as follows: grounded battery, conductors 30 and 47, winding of magnet 29,
  • a pivoted arm 54 carries a swinging pawl 50 which is spring-pressed outwardly upon movement of bar 9, motion of pawl 50 being limited by a'pin 51 mounted on armature 36.
  • magnet 29 retracts its armature, the hook-shaped portion 52 of pawl 50 engages pin 51.
  • relay 1'3 deen'ergizes and-"c following circuit for magnet 17 ground
  • Magnet'29 attracts its armature 36, and by means of the arm 50, 'in engagement with pin 51, causes downward movement of spring 58, which places the restoring arm 59 in' position to'engage' the projection 61 on trunk bar 9.
  • the crankshaft'60 upon its rotation, returns the trunk bar '9 to normal by means of the arm 59, whereupon the lu'g'10 is withdrawn from engagement with bar 8.
  • the bar-8 s thereupon restored to its normal position by virtue of the "resiliency of the spring contacts 2, 3.
  • a switching device a plurality of fixed contacts, incoming lines multipledto certain ones of said fixed contacts, outgoing lines multipled to others of said fixed contacts, resilient projecting portions integral with certain ones of said fixed contacts, a movable bar individual to each incoming line, a movable bar individual to each outgoing line,'and means to establish a connection between an incoming line and an outgoing line as a result of the successive movements of said resilient projecting portions upon operation of an incoming li ne bar and an outgoing line bar.
  • a switching device a plurality of fixed contacts, incoming lines multipled to certain ones of said fixed contacts, outgoing means to operate: said resilient "projecting port-ions in separate successive movements to establish a connection between an incoming' line-and an "outgoing line.
  • multiply connected fixed contacts arranged in vertical rows multiply connected fixed contacts arranged in horizontal rows, an incoming line connected to each vertical row of contacts, an outgoing line connected to each horizontal row of contacts, resilient projecting portions integral with said vertically arranged fixed contacts, a plurality of vertical bars, a plurality of horizontal bars, means to move a vertical bar to displace a. row of projecting portions, and means to operate a horizontal bar to further displace line.
  • a switching device multiply connected fixed contacts arranged in vertical rows, multiply connected fixed contacts arranged in horizontal rows, an incoming line connected to each vertical row of contacts, an outgoing line connected to each horizontal row of contacts, resilient projecting portions integral with said vertically arranged fixed contacts, a vertically movable bar individual to each incoming line, a horizontally movable bar individual to each outgoin line, a plurality of cam'surfaces car ried y each of said horizontal bars equal in number to the number of vertical bars, means to move a vertical bar to displace a row of projecting portions into a position wherein they may be engaged by the adjacent cam surfaces of horizontal bars, and means to operate a horizontal bar to cause said set of projecting portions to be further displaced by the action of oneof said cam surfaces to establish connection between an incoming and an outgoingline.
  • a movable bar individual to each incoming line means to establish a connection etween an incoming and an outgoing line upon operation of an incoming line bar and an outgoing line bar, means to restore an operated incoming line bar to its normal position after connection has been established, and means to restore said operated outgoing line barwhen connection is no longer desired.
  • a switching. device a plurality of fixed contacts, incoming lines multipled to certain ones of said fixed contacts, outgoing lines multipled to others of said fixed contacts, a movable bar individual to each incoming line, 'a movable bar individual to each out oing line, means to establish a connection etween an incoming, and an outgoing line upon operation of an incoming line bar and an outgoin line bar, means to operate an incoming line ar, and means controlled by the operation of an incoming line bar to operate an idle one of said outgoing line bars.

Description

F. A. LUNDOUIST. CROSS BAR LINE SWITCH. APPLICATION FILED NOV-27.1916.
Patented May 6, 1919.
v //1 van far.-
fiwn/r A. A 407476019X by UNITED STATES PATENT OFFICE.
FRANK'A. RUNDQUIST, OF NEW YORK, N. Y., ASSIG-NOR TO WESTERN ELECTRIC COMPANY, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.
' CROSS-BAR LINE-SWITCH.
Patented May 6, 1919.
Application filed November 27, 1916. Serial No. 138,612.
To all whom it may concern:
Be it known that I, FRANK A. LUNDQ'UIST, a citizen of'thelinficd States, residing at New York, in the county ofNew York and State of New York, have invented certain new and useful Improvements inCross-Bar Line-Switches, of which the following is a full, clear, concise, and exact description.
This invention relates to switching mechanisms for use in telephone systems, and more particularly to switches of the cross-bar type, that is, switches in which interconnection between incoming and outgoing lines is effected by the cooperative action of a bar in one of two sets of intersecting bars with a bar in the other of such sets. i
The principal object of this invention is to effect the interconnection of lines in a cross-bar switch by the actuation of the corresponding sets of contact terminals in response to the successive longitudinal movements of a pair of intersecting cross-bars.
The switch herein disclosed is adapted to be used as a line switch or trunk finder, and
as such, may be arranged to. serve a plurality of subscribers lines and a corresponding plurality of trunk lines.
In a preferred embodiment of the invention, each individual switchin apparatus com rises a contact bank in w ich incoming ine terminals are multipled vertically, and outgoing line terminals are multipled horizontally across the bank. These termi nals are in the form of projecting contact springs which are in operative relation to each other at the various points of intersection of the rows formed by them. Individ ual to each set of incomin line multiples is a longitudinally movablefi) ated with each set of outgoing line multiples is a-bar, movable longitudinally in a direction at ri'ht angleslto the direction of motion of the are individual to the incoming lines. At the points of intersection of these auxiliary bars means are rovided for efiecting the interconnection 0 two sets of terminals upon the successive actuation in a longitudinal direction of two intersectina auxiliary bars.
In the drawings, Figure 1 is a perspective view of a section ofthe switch structure showing the terminal bank with its projecting spr'ingcontacts and theauxiliary crossbars for effecting an interconnection of the er, and asceispring contacts. In .Fig. 2, is shown a. schematic representation of the operating mechanisms and the circuits of a switch embodying the features of this invention. Fig. 3 is a detached view showing-a part of the operating mechanism in one stage ofits operation.
Referring to the drawings, incoming lines, such as L L terminate ma contact bank 1 in multiples such as 2, 3, which have the form of contact springs and extend in a vertical direction across. the panel, and outgoing lines or trunks T T terminate in multiples 4, 5, which are likewise in the form of contact springs-and extend horizontally across the contact bank. A plurality of line bars 6, each individual toa set of multiples of an incoming line and suitably mounted to permit of a vertical movement thereof, extend across the panel. Each bar 6 is provided with projections 7, each associated with a bar -8 of non-conducting material rigidly secured to each pair of line, terminals 2, 3. Means are provided-for causing a vertical movement of a line bar 6 u onthe initiation of a call over the line L,, 2 with which such bar 6 is associated. whereupon the non-conducting bars 8 are raised to place them in operative relation with lugs 10 on horizontal trunk bars 9. The trunk bars 9, individual to each set of trunk multiples, are mounted in such a manner as to be capable of movement 1n a longitudinal direction. The depressed lugs 10 integral with the trunk bar 9 are each associated with a bar 8, and are shaped in a manner such that, upon the horizontal movement of a trunk bar 9, a bar 8 individual to the multiples of a line L L and previously positioned by a line bar 6, will be engaged by a lug 10 on the actuated trunk bar and raised thereby to cause the engagement of the contact points 11 and 12 o t .c calling line multiple contact springs 2, 3 with the idle trunk multiples 4, 5. The line L L is thereby extended to the trunk T T The invention will be best understood and the features thereof best ap ear, from a description of the operation 0 a switch, of the character described, in connecting the line with an idle trunk.
Upon the initiation of a call over the line L L relay 13 is energized over a circuit extending from ground, right-hand windfront contact of relay 13, conductor 18, contacts 19, magnet 17, to ground.- The magnet 17 attracts its armature 21, and by means of a pawl 22 pivotally mounted at the extremity thereof, raises'the line bar 6. By means of the projections 7 thereon, all the bars 8, associated with multiples 2, 3, of the line L L are raised into a position to be engaged by the downwardly bent portion of the lugs 10 upon movement of any trunk bar 9. Bar 6, upon its upward movement, closes at contacts 28 a circuit for trunk bar release magnet 29 as follows: grounded battery, con-.
ductor 30, magnet 29, normally closed contacts 31, conductor 32, conductors 33, 34, contacts 28, conductor 35, to ground. Magnet 29 in attracting its armature 36 disengages catch 56 from a projection 37 onthe trunk bar 9. The bar 9 on being released is raised an additional amount, and contactsmoved in a horizontal direction under the action of a spring 38, whereby the inclined section of the lug 10 rides under one of the previously raised bars8. The bar 8 is thus points 11, 12 thereupon engage the multiple spring contacts 4, 5 of the trunk T T Simultaneously with the upward movement of the bar 6, pawl 22 causes the partial clockwise rotation of a sector 23 which is rotatably mounted on a pin 24 fixed to the frame (not shown). A pawl 25 pivoted on a pin 39 thereupon drops into a recess or notch 26. As a result of this operation cont-acts 15 and 19 are opened, and contact 27 is closed, as is more clearly indicated in Fig.- 3, which shows sector 23 in rotated position. At contact 19 the circuit for magnet 17 is opened and magnet 17 thereupon releases its armature 21. Pawl 22 disengages notch 40 in sector 23, and also disengages the line bar 6v which then falls back, and allows the bars 8, associated with the remain? ing multiples of line L and L to return to their normal positions out of operative relation with the lugs 10 of any trunk bars 9 that may be subsequently operated. Pawl 22 will take the position shown in Fig. 3, and will thereby place a Vertically extending projection 42, integral therewith, inoperative relation with a cup-shaped projection 43 on pawl 25.
At contacts 15, the circuit for relay 13 is broken, but relay 13 will remain energized over a new circuit closed for its left-hand winding immediately upon the extension of line L L to the trunk T T through the stepping relay SR of the succeeding selector or connector switch. This circuit will be as follows: grounded battery, left-hand windwill control the step-by-step operation of the particular switch to which it is individual.
Upon the actuation of the trunk bar 9, the
movementof an arm 45 carried thereby allows contact 62 to be closed. Contact 46 is not closed, however, as long as magnet 29 is energized since a hook-shaped member 70 carried by armature 36 engages a projection 71 on spring 72 and prevents the operation of these contacts. The closure of contact 62 maintains magnet 29 energized over a circuit from grounded battery, conductor 30, winding of magnet 29, contact 62, conductor 63, to ground at the armature and back contact or relay RR, which is a relay at the succeeding switch next to be-operated. The relay RR is preferably the first slow. relay of any well-known type of step-b3 step selector switch, and will be energized when such switch is taken for use and will remain energized until the release of the switch. After the calling line has been extended to such selector switch, the relay RR will be energized and will open the circuit of 'magnet 29. which thereupon denergizes. The retraction of the armature 36 allows contact 46 to be closed.
A call coming in on any line other than L L during the busy condition of the latter will cause the release of trunk bar 9 upon the closure of a set of contacts 28 associated with the line bar of such other calling line. The extended starter circuit for magnet 29 will be as follows: grounded battery, conductors 30 and 47, winding of magnet 29,
contact 48, conductor 49, contacts 46 and 72,
conductors 32-, 33 and 34, contact 28, conductor 35 to ground. v
A pivoted arm 54 carries a swinging pawl 50 which is spring-pressed outwardly upon movement of bar 9, motion of pawl 50 being limited by a'pin 51 mounted on armature 36. When magnet 29 retracts its armature, the hook-shaped portion 52 of pawl 50 engages pin 51. I
A restoring arm 59 is pivotally mounted on a constantly rotatin crank arm 60, and is normally held out of engagement with a pro ection 61.0n trunk bar 9 by means. of a fiat spring 58 mounted on arm 54. The arm 59 slides through a suitable guide 73 mounted on the end'of spring58. Arm 54 is held in its normal position by the action of a fiat spring 57.
receiver, relay 1'3 deen'ergizes and-"c following circuit for magnet 17 ground,
reeageec hen the circuit over line L L2 en, upon the subscriber 'ha'ngingup hi oses the ma net 17, conductor '64, contact '27, armatui'e and back contact of relay 13, to grounded battery. Magnet 17:attracts its armature, and pawl '22, previously positioned as shown in Fig. -3, is "'given'an upward movement,'and"by means of the projection 42 thereon raises pawl 25 out of the notch'26 in the sector thusp'ermitting the restoration of the sector 23 and "its associated contacts 15, 19 and 27. Simultaneously relay RR of the succeedin switch is deenergized and places 'groun on conductor 63,
completing thereby "the following circuit for magnetf29 grounded' battery, conductor 30, magnet 29, contacts 62, conductor 63, armature and-back contact of relay RR, to
ound.-
Magnet'29 attracts its armature 36, and by means of the arm 50, 'in engagement with pin 51, causes downward movement of spring 58, which places the restoring arm 59 in' position to'engage' the projection 61 on trunk bar 9. The crankshaft'60, upon its rotation, returns the trunk bar '9 to normal by means of the arm 59, whereupon the lu'g'10 is withdrawn from engagement with bar 8. The bar-8 s thereupon restored to its normal position by virtue of the "resiliency of the spring contacts 2, 3.
Trunk bar 9, on being restored to normal, opens contacts 62, breaking thereby. the circuit for magnet 29. Magnet '29 retracts its armature, a catch 56 thereon engaging a projection '37 on the trunk bar 9 and holding it in its normal position. Bar 9 also forces arm 50 out of engagement with pin 51, allowing arm 5-1 to return to normal. Arm 5* is restored and retains the reciprocating restoring member 59 in its normal 1noperative position by means of spring 58.
\Vhat is claimed is:
1. In a switching device, a plurality of fixed contacts, incoming lines multipledto certain ones of said fixed contacts, outgoing lines multipled to others of said fixed contacts, resilient projecting portions integral with certain ones of said fixed contacts, a movable bar individual to each incoming line, a movable bar individual to each outgoing line,'and means to establish a connection between an incoming line and an outgoing line as a result of the successive movements of said resilient projecting portions upon operation of an incoming li ne bar and an outgoing line bar.
2. In a switching device, a plurality of fixed contacts, incoming lines multipled to certain ones of said fixed contacts, outgoing means to operate: said resilient "projecting port-ions in separate successive movements to establish a connection between an incoming' line-and an "outgoing line.
3. In a switching device, a plurality of fixed contactsg-incomin'g lines multipled to certain ones ofsaid fixed contacts, outgoing lines multipledto others of said fixed contacts, resilient. projecting portions integral with certain ones of'said' fixed contacts, a movable bar individual to'each incoming line, a movable bar individual to ea'ch:outgoing line, means to'advancea setofresili ent projecting portions into one. stage of operation upon actuation of an incoming line bar,"and means to'advance said portions to a second stage of-operation upon actuation of an'outgoing line bar'to establish a. connection between'an incoming and an outgoing line. I
'4.'In a switching device, fixed contacts, incomin of said xed contacts, outgoing lines multipled to others of said fixed contacts, resilient projecting portions integral with certain ones of said fixed contacts, a movable her individual to each incoming 'line,'a' movable bar individual to each outgoin line, means to operate an incoming line arto displace certain ones of said projecting portions, and means 006 erative with.a projectin portion in its isplaced position and opera le' upon movement of an outgoing lines multipled to certain ones line bar to establish connection between an incoming and an outgoing line.
5. In a switching devlce, multiply connected fixed contacts arranged in rows, said rows being arranged in groups,-an incoming line connected to each row of contacts in one of said groups, an outgoing line connected to each row of contacts in a second one of said groups, sets of resilient projecting portions integral with the fixed contacts and means to operate an outgoing line bar to further displace one of said sets of projecting portions to establish connection between an incom ng and an outgoing line.
6. In a switching device, multiply connected fixed contacts arranged in vertical rows, multiply connected fixed contacts arranged in horizontal rows, an incoming line connected to each vertical row of contacts, an outgoing line connected to each horizontal row of contacts, resilient projecting portions integral with said vertically arranged fixed contacts, a plurality of vertical bars, a plurality of horizontal bars, means to move a vertical bar to displace a. row of projecting portions, and means to operate a horizontal bar to further displace line.
said projectingportions to establish connectlon etween an incoming and an outgoing 7. In a switching device, multiply connected fixed contacts arranged in vertical rows, multiply connected fixed contacts arranged in horizontal rows, an incoming line connected to each vertical row of contacts, an outgoing line connected to each horizontal row of contacts, resilient projecting portions integral with said vertically arranged fixed contacts, a vertically movable bar individual to each incoming line, a horizontally movable bar individual to each outgoin line, a plurality of cam'surfaces car ried y each of said horizontal bars equal in number to the number of vertical bars, means to move a vertical bar to displace a row of projecting portions into a position wherein they may be engaged by the adjacent cam surfaces of horizontal bars, and means to operate a horizontal bar to cause said set of projecting portions to be further displaced by the action of oneof said cam surfaces to establish connection between an incoming and an outgoingline. 8 In a switching device, a plurality o fixed contacts, incoming lines multipled to certain ones of said fixed contacts, outgoing lines multipled to others of said fixed conmoans;
tacts, a movable bar individual to each incoming line, a movable bar individual to each out oing line, means to establish a connection etween an incoming and an outgoing line upon operation of an incoming line bar and an outgoing line bar, means to restore an operated incoming line bar to its normal position after connection has been established, and means to restore said operated outgoing line barwhen connection is no longer desired.
9. In a switching. device, a plurality of fixed contacts, incoming lines multipled to certain ones of said fixed contacts, outgoing lines multipled to others of said fixed contacts, a movable bar individual to each incoming line, 'a movable bar individual to each out oing line, means to establish a connection etween an incoming, and an outgoing line upon operation of an incoming line bar and an outgoin line bar, means to operate an incoming line ar, and means controlled by the operation of an incoming line bar to operate an idle one of said outgoing line bars. a
In witness whereof, I hereunto subscribe my name this 24th day of November, A. D. 1 16.
FRANK A. LUNDQUIST.
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Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3529113A (en) * 1966-10-20 1970-09-15 Int Standard Electric Corp Miniature crossbar switch with flexible tape selecting means and mechanical latch
US8559825B2 (en) 2010-12-19 2013-10-15 M. Hassan Hassan Digital communication method and system

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3529113A (en) * 1966-10-20 1970-09-15 Int Standard Electric Corp Miniature crossbar switch with flexible tape selecting means and mechanical latch
US8559825B2 (en) 2010-12-19 2013-10-15 M. Hassan Hassan Digital communication method and system

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