US1146889A - Telephone-exchange system. - Google Patents

Telephone-exchange system. Download PDF

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US1146889A
US1146889A US74937813A US1913749378A US1146889A US 1146889 A US1146889 A US 1146889A US 74937813 A US74937813 A US 74937813A US 1913749378 A US1913749378 A US 1913749378A US 1146889 A US1146889 A US 1146889A
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line
springs
terminals
shaft
engagement
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US74937813A
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Frank A Lundquist
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AT&T Corp
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Western Electric Co Inc
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04QSELECTING
    • H04Q3/00Selecting arrangements

Definitions

  • trunks The contact actuating members of associated therewith are dispensed with.
  • These selectors which, in the present emmay be arranged in groups associated with all the switches of a group always stand in the same position adjacent to or directly Z over the multipled terminals of an idle trunk. When a subscriber lifts his receiver from the hook, his line, which is connected to one of these switches, immediately becomes connected to an idle trunk. .Then this switch together with all other switches of the group advances to the next idle trunk.
  • One of the objects of this invention is the provision of an improved switch of this type having no brushes or Wipers.
  • Another object is the provision of a looking device independent of the contact actuating means whereby the contacts may be retained in their actuated position.
  • a further object is the provision of a switch of simple structure having few movable parts.
  • the apparatus herein disclosed comprises essentially a circular or cylindrical bank of contact springs comprising multipled termirials of the line to which the switch is individual, and trunk line terminals adapted to cooperate therewith. Mounted axially of which the shaft passes. This collar is pro-.
  • Figui-c l is a perspective view, partly in section, of thereof;
  • Fig. 3 is a sectional view on the line 33 of Fig. 2, and
  • Fig. 4-. is a diagrammatic view of the device and a circuit arrangement the switching device;
  • Fig. 2 is a plan view with which it is adapted to be used.
  • 1 and 2 are circular plates rigidly secured together .Tii'ounted upon the plate 2 and concentrically therewith is a cir cular terminal bank 4 consisting of ten sets of stationary terminals, each set of which comprises a pair of springs 5 and 6 which represent the terminals of a subscribers line. These line terminals are all multiply connected by being formed as inwardly extending fingers on the circular plates 7. Associated with each pair of line springs and located therebetween is a'pa-ir of coiiperating springs 8 and 9 which represent the terminals of atrunk line or connecting circuit as T, or T? towhich thejcal ling line is adapted to be connected.
  • a rotatable and longitudinally movable shaft 10 mounted in bearings 11 and 12, one'of which (11) is formed in a'bracket member 13 secured to the circular disk 1, the other of which (12) is carried by a forwardly projecting bracket, 14 integral with the upright 15 rigidly secured at one side of the plate 2.
  • a sleeve or collar 16 Rotatably mounted in theplate 2 is a sleeve or collar 16 through which the shaft loosely passes.
  • This sleeve is provided at one end thereof with an outwardly projecting arm 17 which forms the armature of theelectromagnet C mounted on the plate 1.
  • This armature carries an outwardly extending pin- 18 for a purpose to be hereinafter de-.
  • a collar 25 Fixed to the shaft 10 above the sleeve 16- is a collar 25 provided With an outwardly extending arm 26 to the outer end of which is secured a knob of insulating material 27.
  • This contact operating arm is so positioned upon the shaft that in the normal position of the device it will occupy a plane slightly above the uppermost line spring 5.
  • an electromagnet 13 Mounted on thebracket member 14 is an electromagnet 13 having an armature 28 which, upon attraction thereof, is arranged to longitudinally displace the shaft 10 against the resiliency of the supporting spring 29.
  • each set of connection springs Arranged on the terminal bank above each set of connection springs is a pair of multiply connected springs 41 and 42'adapted to close the circuit for an electromagnet G1 which controls the movement of the power shaft.
  • These' springs are formed as inwardly projecting parts of the circular members 43 and 44.
  • Fixed to each spring 5 is an upwardly pro ect1ng spacing member 45 having a lug 46 projecting through a spring 42 and into engagement with a'spi'ing 41. This member, whenthe spring 5 is in its normal position, holds the springs 41 and 42 elevated so that they will not be engaged by the insulating knob 27 on the arm 26 when the shaft is rotated.
  • Magnet 61 upon attracting its armature 62 releases the dog 63, the pivot 64 of which is mounted in the annular flange 65 at the endv of the, shaft 33.
  • This flange is provided at the inner surface thereof with a' circular notch 66 which is slightly greater than a semi-circle.
  • the pivot pin 64 is provided with a notch'or cut away portion 70 within which the flange (38 freely rotates when the dog 63 is in its re tracted position.
  • the armature 62 will be retracted by the spring 71, and when the shaft 38 has made one complete revolution, the dog (33 will be caught by the catch member 73 at the end of the armature (32, thus rotating the pivot pin 64 and releasing the shaft 38 from the consta-itly rotating member 69.
  • the wormwheel 40 is pro vided with ten teeth, it will be; seen that the revolution of the worm 39 has ,advanced the contact operating member 27one-tenth of i one revolution, thus placing it in operativerelation-to the next set of contact springs.
  • the spacing member 45 thereat will be removed from engagement with the springs 41,42 and the member 27 of'said switch will thus cause engagement of said springs to effect another revolution of the shaft 38, and so on until the contact operating member 27 has reached a position in operative relation to a set of springs associated with an idle trunk so as to be in a position to immediately connect the next calling line thereto.
  • a telephone line a switch associated therewith, pairsof multiply connected terminals of said line at said switch, trunk terminals arranged for engagement with said line terminals respectively, a contact actuating member, means for moving said member in one direction to select a set of contacts, means for moving it in another direction to cause interengagement of the contacts of said set, and a locking device acting independently of said contact actuating member for retaining said "set of contacts in" their actuated pos1tion.
  • a subscribers line a switch associated therewith, sets ,of sta tionary contact springs arranged for interengagement at said switch, certain springs of each set representing multipled terminals of said line, other springs of each set i being trunk line terminals, a contact operating device for causing engagement of line terminals with the terminals of an idle trrnk upon the initiation ofa call, means independent of said contact operating device for retaining said terminals in engagement,
  • a circular bank of contacts at said switch said bank comywherein are terminals of an idle trunk, upon prising contact sets in each of which are represented terminals of said line and of a trunk line, means whereby, upon the initiation of a call, 'one of said setsof contacts Will be actuated to connect the calling line to anidle trunk, andmechanism independent of said contact actuating means for retaining the contacts of said set in. engage ment.
  • a locking member having a shaft extending axially through sa d bank, a cont'act'act-uating 1nem a plurality offingers, said fingers being a normally located intermediate said sets of" H springs, respectively, means for moving said shaft longitudinally to actuate one vof said" sets-of-springs, means for rotating said locking member to operatively engage one of said fingerswith'a spring of the actuated set whereby said. springs are held in engagement, and means for rotating said shaft whereby-said contact actuating member is moved to operative relation to a contact set,

Description

F. A. LUNDQUIST. TELEPHONE EXCHANGE SYSTEM. APPuqAfloN FILED FEB. 19. 1913.
Patented July 20, 1915.
3 SHEETS-SklEEI 2.
- mm. L uhdqu/st 7 STATES PATENT oEEIcE.
FRANK A. L NnoUIs'r, oE INGLESIDE, ILLINOIS, ASSIG-NOR TO WESTERN ELEc'rEIc COMPANY, OF NEW YORK, N. Y., A CORPORATION OF ILLINOIS.
TELEPHONE-EXCHANGE SYSTEM.
Patented July 20, 1915.
Application filed February 19, 1913. Serial No. 749,378.
To all whom it may-concern Be it known that I, FRANK A. LU D UIsT,
a citizen of the United States, residing at and flexible connections or cords necessarily bodiment are illustrated as line switches,-
. trunks. The contact actuating members of associated therewith are dispensed with. These selectors, which, in the present emmay be arranged in groups associated with all the switches of a group always stand in the same position adjacent to or directly Z over the multipled terminals of an idle trunk. When a subscriber lifts his receiver from the hook, his line, which is connected to one of these switches, immediately becomes connected to an idle trunk. .Then this switch together with all other switches of the group advances to the next idle trunk.
In the same way when a second calling subscriber lifts his receiver, his line is immediately connected to the next idle trunk by his switch, and all the switches again advance to the idle trunk next in the series. In this process the switch of the calling subscriber does not stop in a fixed position during talking, but merely connects the calling line to an idle trunk and passes. on. In this passing from trunk to trunk, the contact actuating parts of the switches do not wipe over contacts but pass adjacent to contact springs which are moved into and locked in engagemerit by theoperation of the switches. This locked position is released by hanging up the receiver without respect to what position the switch. may be in.
One of the objects of this invention is the provision of an improved switch of this type having no brushes or Wipers.
Another object is the provision of a looking device independent of the contact actuating means whereby the contacts may be retained in their actuated position.
A further object is the provision of a switch of simple structure having few movable parts.
Other objects and advantages will appear.
'by the spacing blocks'3.
as the description of the invention progresses'.
The apparatus herein disclosed comprises essentially a circular or cylindrical bank of contact springs comprising multipled termirials of the line to which the switch is individual, and trunk line terminals adapted to cooperate therewith. Mounted axially of which the shaft passes. This collar is pro-.
vided with a. plurality of radially arranged projections, one for each set of springs. After the springs of the set, are forced into inter-engagement, this collar is rotated to po sition one of these projections or fingers over the uppermost spring of said set, whereby said springs are held in their engaging relation while the shaft is automatically rotated to position the contact operating finger thereof in operative relation to the next set of springs in which are terminals of an idle. trunk.
Referring now to the drawings for a more complete disclosure of the device,Figui-c l is a perspective view, partly in section, of thereof; Fig. 3 is a sectional view on the line 33 of Fig. 2, and Fig. 4-. is a diagrammatic view of the device and a circuit arrangement the switching device; Fig. 2 is a plan view with which it is adapted to be used.
Referring now to the drawings in which the same reference characters are applied to the same parts in the several figures, 1 and 2 are circular plates rigidly secured together .Tii'ounted upon the plate 2 and concentrically therewith is a cir cular terminal bank 4 consisting of ten sets of stationary terminals, each set of which comprises a pair of springs 5 and 6 which represent the terminals of a subscribers line. These line terminals are all multiply connected by being formed as inwardly extending fingers on the circular plates 7. Associated with each pair of line springs and located therebetween is a'pa-ir of coiiperating springs 8 and 9 which represent the terminals of atrunk line or connecting circuit as T, or T? towhich thejcal ling line is adapted to be connected. Extending axially through the stationary terminal bank is a rotatable and longitudinally movable shaft 10 mounted in bearings 11 and 12, one'of which (11) is formed in a'bracket member 13 secured to the circular disk 1, the other of which (12) is carried by a forwardly projecting bracket, 14 integral with the upright 15 rigidly secured at one side of the plate 2. Rotatably mounted in theplate 2 is a sleeve or collar 16 through which the shaft loosely passes. This sleeve is provided at one end thereof with an outwardly projecting arm 17 which forms the armature of theelectromagnet C mounted on the plate 1. This armaturecarries an outwardly extending pin- 18 for a purpose to be hereinafter de-.
scribed. Extending outwardly from the sleeve 16 at .right angles to the armature member 17 is an arm 19 earrylng a downwardly projecting insulating lug 20 adapted,
when the armature 17 is fully attracted, to
- cause separation-of the normal-1y closed conterminals, and they are so positioned that in the normal position of the sleeve 16 these fingers Will occupy positions intermediate the terminal sets, respectively, as shown in Fig. 2.
Fixed to the shaft 10 above the sleeve 16- is a collar 25 provided With an outwardly extending arm 26 to the outer end of which is secured a knob of insulating material 27. This contact operating arm is so positioned upon the shaft that in the normal position of the device it will occupy a plane slightly above the uppermost line spring 5. Mounted on thebracket member 14 is an electromagnet 13 having an armature 28 which, upon attraction thereof, is arranged to longitudinally displace the shaft 10 against the resiliency of the supporting spring 29. As the insulating knob 27 overlies the spring 5 of one of the sets of stationary contacts or springs, this spring 5 will be depressed into engagement with the spring 8 and spring 9 Will be forced into contact with the spring 6, through the medium of the insulating spacing member '30. The electromagnet C will then beenergized to. rotate the star wheel .23 andinso doingwill-position one of the fingers 24' over the spring 5 of the actuated set of springs. As the other sets of springs are at this time in their normal position the other fingers .24 will pass underneath their respective springs 5 and consequently will have no efiect thereon. It maybe noted that only long enough tooverlie the ends of the ing member 18 of the armature 17 to retain the same in its forward position until the electromagnet A is deiinergized. The attraction of the armature 33 by electromagnet a A is arranged to close a pair of contact springs 36 and 37. Extending adjacent to the shaft 10 of all the line switches of a group is a common drive shaft 38. This shaft is provided with a plurality of worms 39, one for each shaft 10. Rigidly fixed to' the shaft 10 and in operative engagement with its respective worm 39 is a worm wheel 40 through the medium of which the shaft is adapted to be rotated. Arranged on the terminal bank above each set of connection springs is a pair of multiply connected springs 41 and 42'adapted to close the circuit for an electromagnet G1 which controls the movement of the power shaft. These' springs are formed as inwardly projecting parts of the circular members 43 and 44. Fixed to each spring 5 is an upwardly pro ect1ng spacing member 45 having a lug 46 projecting through a spring 42 and into engagement with a'spi'ing 41. This member, whenthe spring 5 is in its normal position, holds the springs 41 and 42 elevated so that they will not be engaged by the insulating knob 27 on the arm 26 when the shaft is rotated. \Vhen,
however, a set of springs is held depressed or in its actuated position, the member is removed from engagement with the springs 41 and 42 and, if at this time the knob 27 is positioned under these springs and the shaft is inits elevated or normal position, these springs will be forced into engagement to complete a circuit for the clutch controlling magnet through the medium of which the power shaft 38 is controlled.
-Reference is now made to Fig. 4 for adescription of the operation of the device and the circuits therefor. Upon the subscriber taking down the receiver a circuit will be completed for the electromagnet A from battery 47, through the battery lead-48. wire 49, coil of electromagnet A, wire 50, side L of the line, the receiver hook and telephone set at the calling station, side L of the line, the resistance 51, wire 52, battery lead-53 and back to battery. Armature 33 is-thereupon attracted to place the spring catch 34 carried thereby in a position to engage the pin 18 carried by the armature 17 and hold it in its operated position until the deenergization-of'elec'tromagnet A. The encrgizafor the electromagnet B from battery 47 lead 48, wires 49, 54, normally closed contacts 22, 21, wire 55, coils of B, wires 57, 58, contacts 37 36, wire 52, lead 53 and back to battery. Upon the attraction of the armature 28 of the eleotromagnet B, the shaft 10 is depressed against the resistance of the spring 29 and the insulating knob 27 carried thereby engages the spring 5 of the set of brushes over which this contact operatving-member is now positioned, causing engagement of the spring 5 with the trunk terminal 8 and the spring 6 with the trunk terminal 9. This connects the calling line with a connecting circuit leading to a selector or a final connector, as theicase may be, and as will hereinafter appear this circuit to whichthe line is connected is always an idle one. The armature 28 in pulling up causes engagement of the contact springs 31 and 32, thus closing. circuit for the electro magnet C from battery 47, battery lead 48, wires 49, 54, springs 22, 21, wire'55, springs 31, 32, wire 56, winding of electromagnet 0,
wires 57 58, springs 37 36, wire 52, battery lead 53 and back to battery. C thereupon attracts its armature 17 rotating the sleeve 16 to position one of the radial extending fingers 24 over the spring 5 of actuated set, thus holding spring 5 in its lowermost position and holding the spring 5 in engagement with the spring 8 and the contact 6 in engagement with contact 9.
When the armature 17 was attracted the pin 18 carried thereby was engaged by the shoulder 35 of the catch spring 34 to retain it in its attracted or forward position, thus assuring that the actuated set of springswill remain in engagement untilthe circuit for the electromagnet A is interrupted at the switch hook by the calling subscriber hanging up his receiver. The rotation of the. sleeve 1.6 caused the projecting lug 20 carried by the arm 19 to engage the lateral proection 59 on the sprmg 22 and as the armature reaches the limit ofits travel, this lug passes from engagement with the spring 22,
and into engagement with a projecting lug 60 carried by the spring 21 in such a manner as to cause disengagement of the con tacts 21 and 22. This interrupts the circuits of the electromagnets B and C. Upon the deiinergization of the electromagnet ll, the shaft is elevated. to its normal position by the spring 29, thus causing the knob 27 to I engage the spring 42, and force it into engagement with the spring 43. This closes the circuit for the clutch magnet 61 of the drive shaft 38 from battery 47,1ead 48, wire 80, plate 44, contacts 42, 41, plate 43, wire 81, wire. 82, coils of electromagnet 61 and back to battery. Magnet 61 upon attracting its armature 62 releases the dog 63, the pivot 64 of which is mounted in the annular flange 65 at the endv of the, shaft 33. This flange is provided at the inner surface thereof with a' circular notch 66 which is slightly greater than a semi-circle. This forms the bearing for the pivot pin 64: l" acat'd within the re cess 67 is a flange '63 11 fl end of a constantly rotating power member (59. The pivot pin 64 is provided with a notch'or cut away portion 70 within which the flange (38 freely rotates when the dog 63 is in its re tracted position. When, however, the dog 63 is released by the attraction of the arm'a ture 62, the pivot pin (34 is rotated by the spring 71 to position a portion of the pin (34 go in one of the notches 72 in the flange (38, thus locking the shaft 38 to the constantly rotating power shaft (59. As the energizing circuit of 'electromagnet 61 will be interrupted as soon as the knob 27 passes from 35 engagement with the particular spring ,42
which it has now actuated, the armature 62 will be retracted by the spring 71, and when the shaft 38 has made one complete revolution, the dog (33 will be caught by the catch member 73 at the end of the armature (32, thus rotating the pivot pin 64 and releasing the shaft 38 from the consta-itly rotating member 69. As the wormwheel 40 is pro vided with ten teeth, it will be; seen that the revolution of the worm 39 has ,advanced the contact operating member 27one-tenth of i one revolution, thus placing it in operativerelation-to the next set of contact springs. If the trunk associated with this set is busy at some other switch, the spacing member 45 thereat will be removed from engagement with the springs 41,42 and the member 27 of'said switch will thus cause engagement of said springs to effect another revolution of the shaft 38, and so on until the contact operating member 27 has reached a position in operative relation to a set of springs associated with an idle trunk so as to be in a position to immediately connect the next calling line thereto.
When the calling subscribed hangs up his receiver the circuit through the relay A will be interrupted, whereby its armature 33 will be retracted. The armature 17 of relay C will now be released from the catch,35 and the collar 16 willbe rotated to release the actuated set of contact springs. When the armature 17 returns to normal the insulating pin 20 carried at the end of the arm 19 1 0 will pass under or back of the projecting port-ion 59 on the spring 22 and when the armature reaches its fully retracted position the springs 21 and 22 will again come together. The apparatus has now been fully 25 returned to its normal position and is ready for another call. It will now be seen that the apparatus when at rest always stands in operative relation to a contact set in which 'an idle trunk lineterminates, thus being in a position-t0 immediatel connect a calling line toan idle connecting circuit.
said line at said switch, other terminals'for engagement with said line terminals, a shaft capable of movement 1n. two. directions whereby said line terminals may be engaged with said other terminals, and independent means for retalnlng said terminals 1n ven-.
gagement.
2. In combination a telephone line, a switch associated therewith, pairsof multiply connected terminals of said line at said switch, trunk terminals arranged for engagement with said line terminals respectively, a contact actuating member, means for moving said member in one direction to select a set of contacts, means for moving it in another direction to cause interengagement of the contacts of said set, and a locking device acting independently of said contact actuating member for retaining said "set of contacts in" their actuated pos1tion. i
V dependent of saidcontact operating means 3. In'combinationa telephone line, an automatic switch associated therewith, pairs of multiply connected contact terminals of said line at said switch, trunkterminals ar ranged for engagement with said line terminals respectively, contact operating means for causing engagement of said line terminals with said trunk terminals, means infor retaining said terminals in their operated position, and means whereby said oper ating means after actuation will-be immediatclv associated with a terminal set wherein are contacts of an idle trunk,
L In combination, a subscribers line, a switch associated therewith, sets ,of sta tionary contact springs arranged for interengagement at said switch, certain springs of each set representing multipled terminals of said line, other springs of each set i being trunk line terminals, a contact operating device for causing engagement of line terminals with the terminals of an idle trrnk upon the initiation ofa call, means independent of said contact operating device for retaining said terminals in engagement,
and means wherebysaid operating meanswillbe immediately associated with the next terminal set wherein-are the contacts of an idle trunk.
5. In combination, a telephone line, an automatic switch associated therew1th,-;sets
of-contact springs arranged for inter-engagement at said switch, springs of each set representing multipled terminals of said line, other springs of each set representing trunk terminals,a rotatable and longitudinally movable shaft, and means whereby, upon the initiation of a call, said shaft will be actuated to operatively connect said line to an idle trunk, and means independent of said'shaft for retaining contacts of the actuated set in engagement.-
G.'In combination, a telephone line, a
switclfiassociated therewith, a circular bank of contacts at said switch, said bank comywherein are terminals of an idle trunk, upon prising contact sets in each of which are represented terminals of said line and of a trunk line, means whereby, upon the initiation of a call, 'one of said setsof contacts Will be actuated to connect the calling line to anidle trunk, andmechanism independent of said contact actuating means for retaining the contacts of said set in. engage ment.
7.'In combination, a telephone line, an'
automatic switch associated therewith, multipled contact terminals ofsaid line at said switch, trunk 11116 terminals arranged for engagement with said line terminals respectively, contact operating means forcausing engagement of said line terminals with said trunk terminals, independently operable locking means for retaining said terminals in engagement, and means whereby said contact operating means 1s moved to operative relation to a contact set, wherein are terminals of an idle trunk line, upon the actuation of said locking means. 7
8. In combination, a telephone line, switch associated therewith, a circular bank of sets of stationary contact springs ara nged for inter-engagement at said switch,
contacts of each set comprising multipled terminals of said line andterminals of a trunk line,
her on said shaft, a locking member having a shaft extending axially through sa d bank, a cont'act'act-uating 1nem a plurality offingers, said fingers being a normally located intermediate said sets of" H springs, respectively, means for moving said shaft longitudinally to actuate one vof said" sets-of-springs, means for rotating said locking member to operatively engage one of said fingerswith'a spring of the actuated set whereby said. springs are held in engagement, and means for rotating said shaft whereby-said contact actuating member is moved to operative relation to a contact set,
the actuation-of said locking means.
. 9.. In an exchange, telephone'lines termie nating thereat, a- ,group of switches -associ-' ated with said lines,-respectively,' sets of contacts at each of saidsWitcheseach-set" comprising multiple t'erminals'of a line and trunk line terminals, a contact actuating member at each switch, and means for movmg the contact actuating members of a group of sw1tches 1n unison whereby said actuating members'when'at rest are alwayslines at said switches respectively, terminals of trunk lines at each of said switches, actuating members, one at each switch for cans ingi engagement of said line terminals with said trunk terminals, and means effective when one of said actuatin members is 0perated for moving all 0 members into association with the terminals of an idle trunk.
In witness whereof, I hereunto subscribe my name this 14th day of February A. 1).,
FRANK A. LUNDQUIST. witnesses:
GEORGE E. FOLK, MCCLELLAN YOUNG.
said actuating 5
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4291238A (en) * 1980-02-04 1981-09-22 Whirlpool Corporation Power switch module

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4291238A (en) * 1980-02-04 1981-09-22 Whirlpool Corporation Power switch module

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