US1830834A - Telephone system - Google Patents

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US1830834A
US1830834A US371016A US37101629A US1830834A US 1830834 A US1830834 A US 1830834A US 371016 A US371016 A US 371016A US 37101629 A US37101629 A US 37101629A US 1830834 A US1830834 A US 1830834A
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winding
armature
circuit
current
resistance
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Irving W Green
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AT&T Corp
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American Telephone and Telegraph Co Inc
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04MTELEPHONIC COMMUNICATION
    • H04M15/00Arrangements for metering, time-control or time indication ; Metering, charging or billing arrangements for voice wireline or wireless communications, e.g. VoIP
    • H04M15/28Arrangements for metering, time-control or time indication ; Metering, charging or billing arrangements for voice wireline or wireless communications, e.g. VoIP with meter at substation or with calculation of charges at terminal

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  • This invention relates to telephone systems and more particularly to a telephone system which includes a measuring devicelocated-at the subscribers station which is adapted to be operated by a constant direct current in the line to measure the length of time the telephone is in use.
  • N p a measuring devicelocated-at the subscribers station which is adapted to be operated by a constant direct current in the line to measure the length of time the telephone is in use.
  • Thedrawing represents diagrammatically a telephone system illustrating one embodiment of the invention.
  • stations A and B are shown with subscribers loops extending to the central othce and terminating-in the jacks 2d and 24;.
  • A represents the station of the calling subscriber andB that of the called subscriber.
  • Substation A comprises the usual transmitter 1, the receiver 2, the receiver hook 3, contacts 4, induction coil 5, ringer 6 and capacity 7.
  • a meter M connected in series with the-substation circuit with a by-pass condenser 8 provided to permit the voice signals to pass therethrough rather than through the meter winding.
  • he meter M as shown, includes an electroinagnet 9, the core of which is laminated, having a winding 10 and poles P and P A pivoted balance wheel 12 ofnon-magnetic It is obvious that any artificial 1929. Serial No.. 371,016.
  • a makebefore-break switch including the contact springs 19, 20 and 21 is positioned in such a mannerthat, as the balance wheel oscillates, the bar member 22, located thereon, will come in contact with the spring 19 and cause it to make contact with the spring 21 and then I break the normally existing contact between the springs 20 and 21.
  • the establishment of the contact between the springs 19 and 21 connects the resistance 23 in parallel with.
  • the resistance 23 is substantially the same in value as that of the winding 10, the resistance of each being as low as practicable.
  • the cord circuit C of the central ofiice is here illustrated as the impedance coil feed type. Obviously, a cord circuit of the repeating coil feed type may be used, if desired.
  • the cord circuit shown comprises the usual current source 25, grounded at 26, a current supply bridge comprising impedance coils 27, capacities '28 and 29, cord conductors 30, 30, 31 and 81 and the supervisory relay 32.
  • the current is normally supplied to thevoalling line through the leads. 33 and 33, the contacts 341 and 34, the armatures 85 and 35, the left-hand impedance coils 27 and the cord conductors 30 and 81, and to the called line through the leads 36 and 36', the right-hand impedance coils 27 and the cord conductors 30 and 31.
  • a switching means under the control of the relay 32 is provided to reverse the polarity of the current in the calling line through the leads 37 and 37" and the contacts 33 and 38'.
  • This" switching means includes a relay 39, grounded at 40', the lead ll, the contact 42, the armature 13 and the battery 44, grounded at 45.
  • the operation of the system is as follows: When the ca ing subscriber at station A removes his re'" irer from the hool: to initiate a call, the operator in response to the signal establishes a connection to the central ottice through the jack 2% in the well known manner. At this time, the current flows from the positive terminal of the source 25, through.
  • the lead 33 the contact 3st, the armature 35', upper left impedance coil 2'7, the cord con-- ductorfiO, the jack 2%, the induction coil 5, the contact l, the receiver iook 3, the transmitter 1, the spring 21, the spring 20', the winding 10, back through the jack 24, the cord conduc or 31, the lower left impedance coil 27', the armature 35, the contact 3+1 and the lead 33 to the negative terminal of the source 25.
  • the pole P With this direction of current flow. through the winding 10, the pole P becomes a north pole and a-south pole.
  • the magnet 15 is repulsed and the balance wheel 1 (Ell'lfilBS in its normal, biased position, as shown, and hence no registration occurs.
  • the pole P With this direction of current fiow through the winding 10, the pole P becomes a south pole and P a north pole.
  • the north pole of the magnet 13 is attracted toward the pole P and the south pole of the magnet 13 is attracted toward the pole P which causes the balance wheel 12- to rota-te, as shown, in a counter-clockwise direction in opposition to. the force. exerted by the coil spring 15; 'This rotation causes the pawl 16 to advancethe ratchet wheel 17 one step.
  • Vhen the Winding 10 is disconnected, the pole P and P are demagnetized and the balance wheel 12 rotates back to its normal, biased positionu-nder the influence of the force exerted by the coil spring 15 and the springs 19 and 21.
  • the force exerted by the bar member 22cm: the spring 19 is removed which, first, permits the contact between the springs 26): and 21 to be I'St&b'
  • the current reversing means is connected on one side of the cord circuit only since, in general, it is desirable to charge the call to the calling subscrib er only. It is obvious, however, that such means may be applied to other types of charging systems, for example to a system in which it is desirable to charge the call to the called subscriber only or to a system in which it is desirable to charge the call to both the calling and the called subscribers.
  • the association of said reversing means with the cord circuit may be under control of other means than the relay 32 and in such a manner that the operation of the meter will begin at any desired time during the connection.
  • Vhile this invention has been illustrated in connection with a typical cord circuit using manual operation, it is apparent that it is equally applicable to machine switching apparatus.
  • an electromagnet connected in series with the calling line of a telephone system, a pivot-ed armature adapted to move back and forth under the influence of said magnet and having a predetermined" frequency of vibration, means for registering the number of times said armature vibrates, a resistance of substantially the same value as that of the winding of said electromagnet, and means operated by the movement of said armature for connecting said resistance in parallel with said winding and for opening the circuit of said winding.
  • an electromagnet a pivoted armature adapted to move back and forth under the influence of said magnet and having a predetermined period of'vibration, means for registering the number of times said armature vibrates, an impedance of substantially the same value as that of the winding of said electromagnet, and means operated by the movement of said armature for connecting said impedance in parallel with said winding and for opening the circuit of said winding.
  • an electromagnet an electromagnet, an armature adapted to be operated by said magnet, means for registering the number of times said armature operates, impedance means of substantially the same value as that of the winding of said electromagnet, and means controlled by the operation of said armature for connecting said impedance means in parallel with said winding and for opening the circuit of said winding.
  • amakebefore reak switch including a'plurality of contact springs and adapted to connectsaid resistance in parallel with said winding and open the circuit ofsaid winding as said arm'ae ture moves to itsoperated position and to disconnect said resistance and close the circuit of said windingas said armature moves from its operated position.
  • armature adapted to move back and forth under theinfluence of said magnet, means for registering the number of times said armature vibrates, a resistance of substantially the samevalue as that of the winding of said electromagnet, means controlled by the movement'of said.
  • armature for connecting said resistance in parallel with said winding and .for opening the circuit of said winding, and means associated with said armature and adapted to cooperate with the momentum of said armature and with the magnetic properties of said magnet to cause said armature tohavea predetermined frequency of vibrati'on.
  • a measuring device comprising, in combination, an electromagnet, an armature including abalance wheel and permanent magnet fastened thereto and adapted to rotate back and forth under the influence of said I electromagnet, means for registering the number of times "said armature moves through'its arc of rotation, a c011 spring associated with said armature and adapted to cooperate with the momentum of said armature'and with the magnetic properties of said electromagnet tocause saidarmature to have a predetermined period of vibration, a resi'stance of substantially the same value as that of the winding ofsaid electromagnet, means operated as said armature moves to its operated position for connecting said resistance in parallel with'said winding for opening the circuit of said winding, and means operated as said armature moves from its actuated position for closing the circuit of said winding and for disconnecting said resistance.
  • V L r '7 In a telephone system, subscribers stations, connecting circuits for establishing talking connections between said stations, a current source for supplying talking current to said stations, an electromagnet at each of said stations, the winding of which is normally connected in series with the circuits of said stations, an armature adapted to move back and forth under the influence of said electromagnet, means for registering the number of times said armature vibrates, a
  • a. telephone system subscribers stations, connecting circuits for establishing talking connections'between said stations, a current. source for supplying talking current to said stations, :an 'electromagnet at each of said stations, the Winding of which is normally connected in series with the circuits of said stat-ions, an armature adapted to be operated by saidimagnet, means for registerthe number of times said armature operates, -.a resistance at said stationslof substantially thesame value as that-of said winding vand adapted to be normally disconnected -from the circuits of said stations, and means adapted to connect said resistance in parallel with said winding and open the circuit oat said Winding as said armature moves to its operated positionandto connect said Winding parallel with said resistance and disconnect said resistance as said armature moves tfirom its operated position.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Monitoring And Testing Of Exchanges (AREA)

Description

Nov. 10, 1931. I. w. GREEN TELEPHONE SYSTEM Filed June 14, 1929 INVENTOR BY lWGheeI/z/ ATTORNEY Patented Nov. 10, 1931' UNITED STATES:
PATENT OFFICE IRVING W. GR EN; E cnANEoRn w JERSEY, AssIcrNoE To AME IoAN TELEPHONE I AND TELEGRAPH COMPANY, A CORPORATION OF NEW YORK TELEPHONE SYSTEM Application filed June 14,
This invention relates to telephone systems and more particularly to a telephone system which includes a measuring devicelocated-at the subscribers station which is adapted to be operated by a constant direct current in the line to measure the length of time the telephone is in use. N p
In the telephone metering systems heretofore proposed, in which a meter was located at the subscribers station, it was found necessary in order that the meter be operated at predetermined intervals of time to vary the line current periodically during the conversation. or abnormal variation of the line current will introduce objectionable disturbances in the talking circuit. Consequently, expensive apparatus had to beinstalled in order to eliminate these disturbing effects.
It is an object of this invention to provide a telephone metering system which includes a meter located at the subscribers station and capable of being operated automatically at definite intervals of time by the normal di rect current present in the line,
A better understanding of the invention may be had from the detailed description hereinafter following.
Thedrawing represents diagrammatically a telephone system illustrating one embodiment of the invention. v i
In the drawing two subscribers? stations A and B are shown with subscribers loops extending to the central othce and terminating-in the jacks 2d and 24;. As shown A represents the station of the calling subscriber andB that of the called subscriber. Substation A comprises the usual transmitter 1, the receiver 2, the receiver hook 3, contacts 4, induction coil 5, ringer 6 and capacity 7. In addition, there is located at the substation a meter M connected in series with the-substation circuit with a by-pass condenser 8 provided to permit the voice signals to pass therethrough rather than through the meter winding.
he meter M, as shown, includes an electroinagnet 9, the core of which is laminated, having a winding 10 and poles P and P A pivoted balance wheel 12 ofnon-magnetic It is obvious that any artificial 1929. Serial No.. 371,016.
the magnetic field and of the coil spring 15. r
The movement of said wheel causes the pawl 16, through suitable gearing mechanism not shown, tooperate the ratchet wheel 17. A
holding pawl 18 is provided to hold said ratchet wheel in its operated position. A makebefore-break switch including the contact springs 19, 20 and 21 is positioned in such a mannerthat, as the balance wheel oscillates, the bar member 22, located thereon, will come in contact with the spring 19 and cause it to make contact with the spring 21 and then I break the normally existing contact between the springs 20 and 21. The establishment of the contact between the springs 19 and 21 connects the resistance 23 in parallel with.
the winding 10 of the electromagnet and the breaking of the contact between the springs 20 and 21 disconnects the winding 10 from the circuit. The resistance 23 is substantially the same in value as that of the winding 10, the resistance of each being as low as practicable. V
-The arrangement at substation B is the same as that shown at substation A, as de scribed above.
The cord circuit C of the central ofiice is here illustrated as the impedance coil feed type. Obviously, a cord circuit of the repeating coil feed type may be used, if desired. The cord circuit shown comprises the usual current source 25, grounded at 26, a current supply bridge comprising impedance coils 27, capacities '28 and 29, cord conductors 30, 30, 31 and 81 and the supervisory relay 32. The current is normally supplied to thevoalling line through the leads. 33 and 33, the contacts 341 and 34, the armatures 85 and 35, the left-hand impedance coils 27 and the cord conductors 30 and 81, and to the called line through the leads 36 and 36', the right-hand impedance coils 27 and the cord conductors 30 and 31. In addition, a switching means under the control of the relay 32 is provided to reverse the polarity of the current in the calling line through the leads 37 and 37" and the contacts 33 and 38'. This" switching means includes a relay 39, grounded at 40', the lead ll, the contact 42, the armature 13 and the battery 44, grounded at 45.
The operation of the system is as follows: When the ca ing subscriber at station A removes his re'" irer from the hool: to initiate a call, the operator in response to the signal establishes a connection to the central ottice through the jack 2% in the well known manner. At this time, the current flows from the positive terminal of the source 25, through. the lead 33., the contact 3st, the armature 35', upper left impedance coil 2'7, the cord con-- ductorfiO, the jack 2%, the induction coil 5, the contact l, the receiver iook 3, the transmitter 1, the spring 21, the spring 20', the winding 10, back through the jack 24, the cord conduc or 31, the lower left impedance coil 27', the armature 35, the contact 3+1 and the lead 33 to the negative terminal of the source 25. With this direction of current flow. through the winding 10, the pole P becomes a north pole and a-south pole. The magnet 15 is repulsed and the balance wheel 1 (Ell'lfilBS in its normal, biased position, as shown, and hence no registration occurs. he operator completes the connection'to the alled subscriber B through the jack 24 and emits the ringing current-over the latter This ringing current does not operate --e meter located at the station of the called ubscriber because the meter is made sutciently sluggish in operation to prevent its 'esp se the rapid variation of the ringing 1 7 hen the called subscriber removes 11s from the hook, the circuit inc c relay is closed in the well 45 sure of this circuit ation of the relay 32 to be energized by the closure the connection between the contact l2 and armature lVl-ren it is energized, the attract-s armatures 35 and 35- to connection with the contacts 3% oectively, and to establish their with the contacts 38 and 33, re- This reverses the pol ty of current in the calling line, said current now flowing from the positive terminal of the source 25, through the lead 37, the contact 38, the armature 35, the lower left impedance coil the cord conductor 31, the jack 10, the spring 29, the spring mic-ter- 1, the receiver hook 3, the
contact the induction coil 5, back through the jack the cord conductor 30, the upper left impedance coil 27, the armature 35. the contact 38 and the lead 37 to the negative terminal of the source 25. With this direction of current fiow through the winding 10, the pole P becomes a south pole and P a north pole. The north pole of the magnet 13 is attracted toward the pole P and the south pole of the magnet 13 is attracted toward the pole P which causes the balance wheel 12- to rota-te, as shown, in a counter-clockwise direction in opposition to. the force. exerted by the coil spring 15; 'This rotation causes the pawl 16 to advancethe ratchet wheel 17 one step.
,A stl-Ie balance wheel 12 rotates in this direction, the bar member 22 comes in contact with the spring 19 and first causes it to make c0ntact with the spring 21 which connects the resistancein parallel with the winding 10 and their causes it to break the normally existing contact between springs 20 and" 21 which disconnects the winding 10 from the circuit. The connection of the resistance 23 inthe circuit inm-ied iate-ly before and during the time when the winding 16* is connected substantially prevents the from becomingunbal anced with attendant disturbances in the tal'ki-ngcireuit. Vhen: the Winding 10 is disconnected, the pole P and P are demagnetized and the balance wheel 12 rotates back to its normal, biased positionu-nder the influence of the force exerted by the coil spring 15 and the springs 19 and 21. As the balance Wheel rotates back, the force exerted by the bar member 22cm: the spring 19 is removed which, first, permits the contact between the springs 26): and 21 to be I'St&b'
lished which reconnects thew-inding 10 in the circuit, and, then, permits the contact between the spri i igs 13 and 21 to. be: broken, which disconnects the resistance 23 from the circuit. The poles P and P are again mag netized as before and the cycle is: repeated as long as the connection between the subscribers remains closed. As the. balance. wheel rotates in the direction to operate the ratchet wheel, its momentum causes: it to rotate to a positien in which themagnet 15. is: an appreciable distance beyond the poles. P and. P hen the force. exerted by the coil spring 15 and the sp. ngs 19 and 21 overcomes. the mo inentum, the balance wheel rotates back to ward its normal position. its mementurn causes it torotate: to a position in the magnet. 15- is a mbstaan-tial distance beyond its normal position. When. the magnetic: attraction of the poles. P and P overcomes the momentum, thebalancewheel rotates again in: the direction to operate the ratchet. wheel. Thus, a definite time: interval created between registrations, depending upon. the strength of the magnetic field, the momentum of the: balance wheel and the force: exerted by coil spring 15 and the springs19 and ln'order to prevent false registration due to ringing current and to the flashing of the rerecei-ver hook, the mass of the balance wheel is so selected that the moment of inertia thereof will be sufficient to provide sluggishness of action.
As shown and described, the current reversing means is connected on one side of the cord circuit only since, in general, it is desirable to charge the call to the calling subscrib er only. It is obvious, however, that such means may be applied to other types of charging systems, for example to a system in which it is desirable to charge the call to the called subscriber only or to a system in which it is desirable to charge the call to both the calling and the called subscribers. Likewise, the association of said reversing means with the cord circuit may be under control of other means than the relay 32 and in such a manner that the operation of the meter will begin at any desired time during the connection.
Vhile this invention has been illustrated in connection with a typical cord circuit using manual operation, it is apparent that it is equally applicable to machine switching apparatus.
What is claimed is: r
1. In combination, an electromagnet connected in series with the calling line of a telephone system, a pivot-ed armature adapted to move back and forth under the influence of said magnet and having a predetermined" frequency of vibration, means for registering the number of times said armature vibrates, a resistance of substantially the same value as that of the winding of said electromagnet, and means operated by the movement of said armature for connecting said resistance in parallel with said winding and for opening the circuit of said winding.
2. In combination, an electromagnet, a pivoted armature adapted to move back and forth under the influence of said magnet and having a predetermined period of'vibration, means for registering the number of times said armature vibrates, an impedance of substantially the same value as that of the winding of said electromagnet, and means operated by the movement of said armature for connecting said impedance in parallel with said winding and for opening the circuit of said winding.
3. In combination, an electromagnet, an armature adapted to be operated by said magnet, means for registering the number of times said armature operates, impedance means of substantially the same value as that of the winding of said electromagnet, and means controlled by the operation of said armature for connecting said impedance means in parallel with said winding and for opening the circuit of said winding.
4. In combination, an electromagnet, an armature adapted to be operated by said magnet, means for registering'the number of times said armature operates, a resistance of substantially the same value as that of the.
windin of said electromagnet, and amakebefore reak switch including a'plurality of contact springs and adapted to connectsaid resistance in parallel with said winding and open the circuit ofsaid winding as said arm'ae ture moves to itsoperated position and to disconnect said resistance and close the circuit of said windingas said armature moves from its operated position.
In combination, an electromagnet, an
armature adapted to move back and forth under theinfluence of said magnet, means for registering the number of times said armature vibrates, a resistance of substantially the samevalue as that of the winding of said electromagnet, means controlled by the movement'of said. armature for connecting said resistance in parallel with said winding and .for opening the circuit of said winding, and means associated with said armature and adapted to cooperate with the momentum of said armature and with the magnetic properties of said magnet to cause said armature tohavea predetermined frequency of vibrati'on.-
6. A measuring device comprising, in combination, an electromagnet, an armature including abalance wheel and permanent magnet fastened thereto and adapted to rotate back and forth under the influence of said I electromagnet, means for registering the number of times "said armature moves through'its arc of rotation, a c011 spring associated with said armature and adapted to cooperate with the momentum of said armature'and with the magnetic properties of said electromagnet tocause saidarmature to have a predetermined period of vibration, a resi'stance of substantially the same value as that of the winding ofsaid electromagnet, means operated as said armature moves to its operated position for connecting said resistance in parallel with'said winding for opening the circuit of said winding, and means operated as said armature moves from its actuated position for closing the circuit of said winding and for disconnecting said resistance. V L r '7. In a telephone system, subscribers stations, connecting circuits for establishing talking connections between said stations, a current source for supplying talking current to said stations, an electromagnet at each of said stations, the winding of which is normally connected in series with the circuits of said stations, an armature adapted to move back and forth under the influence of said electromagnet, means for registering the number of times said armature vibrates, a
resistance at said stations of substantially the same value as that of said winding and 7.
adapted to be normally disconnected from the circuits of said stations, and means controlled winding and for disconnecting said winding,
8. .In a telephone system, subscribers stzv' ti ens. connecting circuits for establishingtalk' ing connections between said stations, a cur rent source for supplying talking current to said stations, an electromagnetat each of said stations adapted to be operated at predetermined intervals of time by the talking current and independently of variations thereof, the Winding of said magnet being normally connected in series With the circuits of said stations, :an armature adapted'to move back and tenth under the influence of said magnet and having a predetermined period of zvibrat-ion, means for registering zthejnumber of times said ,armati-ire vibrates, a resistance at said stations of substantially the same value as thatxof said Winding and adapted to be normally disconnected from the circuits of said stations, and means controlled by the movement of said armature for, connecting said resistance in parallel with said Winding and for disconnecting said winding. 7
9.. In a. telephone system, subscribers stations, connecting circuits for establishing talking connections'between said stations, a current. source for supplying talking current to said stations, :an 'electromagnet at each of said stations, the Winding of which is normally connected in series with the circuits of said stat-ions, an armature adapted to be operated by saidimagnet, means for registerthe number of times said armature operates, -.a resistance at said stationslof substantially thesame value as that-of said winding vand adapted to be normally disconnected -from the circuits of said stations, and means adapted to connect said resistance in parallel with said winding and open the circuit oat said Winding as said armature moves to its operated positionandto connect said Winding parallel with said resistance and disconnect said resistance as said armature moves tfirom its operated position.
testimony whereof, I have signed my name to this specification this 12th day of June 1929.. v
IRVING W. GREEN.
Loses-$4
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