US1480659A - Signaling system - Google Patents

Signaling system Download PDF

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US1480659A
US1480659A US428876A US42887620A US1480659A US 1480659 A US1480659 A US 1480659A US 428876 A US428876 A US 428876A US 42887620 A US42887620 A US 42887620A US 1480659 A US1480659 A US 1480659A
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circuit
arc
pair
anode
electrodes
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US428876A
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Quincy A Brackett
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CBS Corp
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Westinghouse Electric and Manufacturing Co
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L27/00Modulated-carrier systems
    • H04L27/02Amplitude-modulated carrier systems, e.g. using on-off keying; Single sideband or vestigial sideband modulation
    • H04L27/04Modulator circuits; Transmitter circuits

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  • My invention relates to wireless-tele' graph-transmission systems and it has particular relation to systems of control that are adapted to control the radiation of energy from are systems.
  • the object of my invention is to provide a control system for are generators that shall be simple in construction and reliable in operation.
  • I-Iitherto in wireless transmission stations.
  • the energy radiated from are systems has been controlled by means of the compensation-wave method and the absorption method.
  • the period of the antenna circuit or, in other words, the length of the radiated wave is cont-rolled by varying the effective inductance of the antenna circuit.
  • This method of control has the disadvantage of causing the radiation of energy at two wave lengths.
  • the oscillating current produced by the arc is caused to oscillate either in the antenna circuit or in the absorption circuit, depending on the energy-loss in the one or the other circuit being the greater.
  • the periods of the two circuitsmust be very nearly equal. The result that forced oscillations are induced in the antenna circuit while the absorbing circuit is functioning, thereby causing a certain amount of energy to be radiated.
  • I employ a system of control which permits of the radiation of energy at one wave length and effectively prevents radiation by forced oscillations.
  • the desired result is accomplished by empassing through the generator 2.
  • the non-radiating circuit may be either ofthe oscillating type or of the nonoscillating type.
  • my inventio I employ a circuit of the latter type.
  • the single figure is a diagrammatic representation of a radio-telegraphtransmission system showing the arrangement of the control system embodying my invention.
  • the transmission system includes an, arc generator 1 which is connected to a source of energy 2 through a pair of reactance coils 4L and an adjustable resistor 5.
  • A. radiating circuit includes a radiating antennafi, a variable inductor 7 an anode 8 and a cathode 9 of the arc generator 1 and a ground conductor 11.
  • the are generator 1 comprises a pair of anodes 8 and 12 and the cathode 9.
  • the condenser 14 prevents sparking between the stationary and movable contactor members of the key 13.
  • the resistance of resistor 15 and portion 17 of resister 5 is substantially equal to'the total antenna resistance. This resistance is the sum ofthe so-called dielectric-absorption resistance, the ohmic resistance and the radiation resistance.
  • the choke coils 4 prevent the high-frequency oscillations from In order to simplify my invention, I havenot shown means for producing a magnetic field and other are refinements well known to the art.
  • an arc is established 'between anode 12 and cathode 9 in any manner well known to the art.
  • the circuit which includes the generator 2, portion 17 'of resistor 5, key 13, condenser 14,
  • resistor 15, inductor l6, anode 12, cathode 9 and inductor 4: functions as an ordinary direct-current arc circuit.
  • the arc is again transferred from anode 8 to anode 12 to establish an arc of the non-oscillating type.
  • the transfer of the are from anode 8 to anode 12 is readily effected because of the well known preference of an are for a circuit causing stable operation to a circuit causing unstable operation. I have found that the transfer of the arc may be more readily effected bymaking the combined resistance of resistor 15 and portion 17 of resistor 5 less than that of resistor 5.
  • Another advantage of my arrangement lies in the fact that a constant load is maintained on the source of energy during both the radiating and non-radiating periods.
  • Still another advantage of my arrange ment is that a relatively small current is broken by the key 13 during a signaling operation, thereby reducing the sparking at the contacts of the key to a minimum value.
  • Still a further advantage of my arrangement is the provision of a controlling circuit permitting a capacitance to be connected in shunt relation to a key to cause a still further reduction in the sparking at the contacts thereof.
  • the method of arc signaling which consists in selectively supplying energy either to an oscillatory circuit or to a non-oscillatory circuit while maintaining uninterrupted operation of the arc.
  • the method of arc signaling which consists in selectively transferring an are from an anode connected to an oscillatory circuit to a second anode connected to a non-oscillatory circuit to control the radiation of energy from said oscillatory circuit.
  • the method of selectively transferring an are from an anode connected to an oscillatory circuit to a second anode connected to a non-oscillatory circuit which consists in varying the resistance of the non-oscillatory circuit.
  • a pair of anodes, a cathode, a radiating circuit connected in shunt relation to one of said pair of anodes and said cathode and means for transferring the are from one of said anodes to the other.
  • An arc-system for radio signaling comprising two electrodes between which an arc is formed, a radiating circuit connected in shunt relation thereto, a third electrode and means whereby the arc may be transferred from one of said pair of electrodes to said third electrode.
  • An arc-system for radio signaling comprising two electrodes between which an arc is formed, a radiating circuit connected in shunt relation thereto, a third electrode and means whereby the arc may be transferred from one of said pair of electrodes to said third electrode to selectively control the flow of energy in the radiating circuit.
  • An arc-system for radio signaling comprising a pair of electrodes between which an arc is formed, a circuit for supplying energy to said are, and a radiating circuit, both in parallel and shunted around said pair of electrodes, a third electrode and means whereby the arc may be transferred from one of said pair of electrodesto said third electrode to control the flow of current in the radiating circuit.
  • An arc-system for radio signaling comprising a pair of electrodes between between which an arc is formed, a circuit for supplying energy to said are, said cir cuit including a resistor and an inductor and a radiating circuit both in parallel and shunted around said pair of electrodes, a
  • An arc-system for radio signaling comprising two electrodes between which.
  • an arc is formed, a radiating circuit connected in shunt relation thereto, a third electrode and key-controlled means whereby the arc may be transferred from one of pair of electrodes to said third electrode.
  • An arc system for radio signaling comprising a pair of electrodes between which an arc is formed, a third electrode, a circuit for supplying energy to said pair of electrodes, said circuit containingan inductor and a resistor, and a radiating system both in parallel and shunted around said pair of electrodes, and a circuit to which the arc may be transferred, said circuit containing said third electrode, one of said first-named pair of electrodes, a resistor, a key, a portion of said first-named resistor, a translating device and an inductor.
  • An are system for radio signaling comprising a pair of electrodes between which an arc is formed, a third electrode, a circuit for supplying energy to said pair of electrodes, said circuit containing an inductor and a resistor, and a radiating system both in parallel and shunted around said pair of electrodes, and a circuit to which the arc may be transferred, said circuit containing said third electrode, one of said firstnamed pair of electrodes, an inductor, aresistor, the resistance of which is substantially equal to the total antenna resistance, a key, a portion of said first-named resistor and a translating device.
  • An arc-system for radio signaling comprising a pair of electrodes between which an arc is formed, a third electrode, a circuit for supplying energy to said pair of electrodes, said circuit containing an inductor, a resistor and a translating device connected in memori relation, and a radiating system both in parallel and shunted around said pair of electrodes, and a circuit to which the arc may be transferred, said circuit containing said third electrode, one'of said first-named pair of electrodes, a resistor, a key, a portion of said first-named resistor and a translating device.
  • An arc-system for radio signaling comprising a pair of electrodes between which an arc is formed, a third electrode, a circuit for supplying energy to said pair of electrodes, said circuit containing an inductor, a resistor and a translating device, and a radiating system both in parallel and shunted around said pair of electrodes, and a circuit to which the arc may be transferred, said circuit having connected in series relation said third electrode, one of said pair of electrodes, a resistor, a key, a portion of said first-named resistor and a translating device.
  • An arc-system for radio signaling comprising a pair of electrodes between Whlch an arc is formed, 'a third electrode, a
  • circuit for supplying energy to said pair of electrodes, said circuit containing an inductor, a resistor and a translating device, and a radiating system both in parallel and shunted around said pair of electrodes, and
  • circuit to which the arc may be transferred said circuit containing said third electrode, one of said pair of electrodes which serves as cathode, a resistor, a key, a portion of said first-named resistor and a translating device.
  • the method of signaling which consists in selectively changing the condition of an arc stream from an oscillatory state to a non-oscillatory state while'maintaining the continuity of said are stream.
  • the method of signaling which consists in selectively causing an arc to energize an oscillatory circuit and a non-oscillatory circuit while continuously maintaining the continuity of the arc tream.
  • the method of signaling which consists in selectively changing the condition ofan arc stream from an oscillatory state to a non-oscillatory state, maintaining the continuity of said are stream during said change and further maintaining the load on the source of supply substantially constant.
  • the method of signaling which consists in impressing upon an idle anode connected to a substantially n0nOscillatOry circuit a relatively higher voltage than that upon a working anode connected toa nonoscillatory circuit to transfer the are from the one anode to the other.
  • a cathode element In an arc generator, a cathode element, a pair of normally stationary anode elements co-operating therewith and means for transferring an are between said elements from one anode to the other.
  • a cathode element In an arc generator, a cathode element, a pair of normally stationary anode elements co-operating therewith and means for transferring an arc between said elements from one anode to the other while maintaining the continuity of the arc.
  • an arc generator comprising a pair of anode elements and a cooperating cathode, means for establishing an are between one of said anode elements and said cathode, means for causing said ar to assume an oscillatory condition, means for transferring said are from the operating anode element to the non-operating anode element and means for changing the operat ing condition of e arc.
  • an arc generator comprising a pair of anode elements and a cooperating cathode, means for establishing an arc-betweenone of said anode element and said cathode, means for causing said are to assume an oscillatory state and means for 5 transferring said are from the operating anode element to the idle anode element while maintaining the continuity of the arc,
  • said last mentioned means including means for changing the are from an oscillatory state to a non-oscillatory state.

Description

Jan. 15, 1924. 1,480,659 Q. A. BRACKETT S IGNALING SYSTEM Filed Dec. '7. 1920 WITNESSES: v INVENTOR 1% Q7 MW Quzgg Afifac/rett ATTORNEY Patented Jan. 15, W24.
UNITED STATES PATENT OFFICE.
QUINCY A. BRACKETT, OF PITTSBURGH, PENNSYLVANIA, ASSIGNOR TO WESTING- HOUSE ELECTRIC & MANUFACTURING COMPANY, A CORPORATION OF PENNSYL- VANIA.
SIGNALING SYSTEM.
Application filed December 7, 1920. Serial No. 428,876.
To all whom it may concern:
Be it known that I, QUINCY A. Bnnonn'r'r, a citizen of the United States, and a resident of Pittsburgh, in the county of Allegheny and State of Pennsylvania, have invented a new and useful Improvement in Signaling Systems, of which the following is a specification.
My invention relates to wireless-tele' graph-transmission systems and it has particular relation to systems of control that are adapted to control the radiation of energy from are systems.
The object of my invention is to provide a control system for are generators that shall be simple in construction and reliable in operation.
, I-Iitherto, in wireless transmission stations. the energy radiated from are systems has been controlled by means of the compensation-wave method and the absorption method.
In the compensation-wave method of con trol, the period of the antenna circuit or, in other words, the length of the radiated wave, is cont-rolled by varying the effective inductance of the antenna circuit. This method of control has the disadvantage of causing the radiation of energy at two wave lengths.
In the absorption-circuit method of control, the oscillating current produced by the arc is caused to oscillate either in the antenna circuit or in the absorption circuit, depending on the energy-loss in the one or the other circuit being the greater. In order to effect the transfer of energy, readily, from one circuit to the other, the periods of the two circuitsmust be very nearly equal. The result that forced oscillations are induced in the antenna circuit while the absorbing circuit is functioning, thereby causing a certain amount of energy to be radiated.
According to my invention, I employ a system of control which permits of the radiation of energy at one wave length and effectively prevents radiation by forced oscillations.
The desired result is accomplished by empassing through the generator 2.
ploying a system of control whereby an arc is swung from an anode connectedto a radiating circuit to a second anode connected to a non-radiating circuit. The non-radiating circuit may be either ofthe oscillating type or of the nonoscillating type. In the operation of my inventio I employ a circuit of the latter type. g
A better understanding of my invention may be had by referring to the accompany ing drawing, in which:
The single figure is a diagrammatic representation of a radio-telegraphtransmission system showing the arrangement of the control system embodying my invention.
Referring to the drawing, the transmission system includes an, arc generator 1 which is connected to a source of energy 2 through a pair of reactance coils 4L and an adjustable resistor 5. A. radiating circuit includes a radiating antennafi, a variable inductor 7 an anode 8 and a cathode 9 of the arc generator 1 and a ground conductor 11. The are generator 1 comprises a pair of anodes 8 and 12 and the cathode 9.
A key 13, a condenser 14: for shunting the key 13, resistor 15 and iductor 16 are included in a circuit which extends from the anode 12 of the arc generator 1 to the re sistor 5. The condenser 14 prevents sparking between the stationary and movable contactor members of the key 13. The resistance of resistor 15 and portion 17 of resister 5 is substantially equal to'the total antenna resistance. This resistance is the sum ofthe so-called dielectric-absorption resistance, the ohmic resistance and the radiation resistance. The choke coils 4 prevent the high-frequency oscillations from In order to simplify my invention, I havenot shown means for producing a magnetic field and other are refinements well known to the art.
The-operation of the system is as follows:
Upona supply of energy to the anodes 8 and 12 and the cathode9, an arc is established 'between anode 12 and cathode 9 in any manner well known to the art. The circuit, which includes the generator 2, portion 17 'of resistor 5, key 13, condenser 14,
resistor 15, inductor l6, anode 12, cathode 9 and inductor 4:, functions as an ordinary direct-current arc circuit. Thus, with the operating key 13 closed, substantially no energy is radiated from the antenna circuit.
Upon opening the key 13, the arc is swung from anode 12 to anode 8. By reason'of the well known negative-resistance characteristic of an are, when shunted by an inductance and a capacitance, high-frequency oscillations are generated in the antenna circuit. Therefore, with key 13 open, a maximum amount of energy is radiated from the antenna circuit.
Upon closing of the key 13, the arc is again transferred from anode 8 to anode 12 to establish an arc of the non-oscillating type. The transfer of the are from anode 8 to anode 12 is readily effected because of the well known preference of an are for a circuit causing stable operation to a circuit causing unstable operation. I have found that the transfer of the arc may be more readily effected bymaking the combined resistance of resistor 15 and portion 17 of resistor 5 less than that of resistor 5.
It can thus be seen that, with the key 1?) closed, substantially no energy is radiated from the antenna circuit, but that, on opening the key, an arc is formed between anode 8 and cathode 9 to supply a maximum amount of energy to the radiatingantenna circuit.
One advantage of my arrangement is the increase in the operating efficiency of an are when supplying energy to an antenna circuit. This increase in eficiency is due to the fact that the anode 8 is maintained in a cooler state than has heretofore been possible without the use of some auxiliary means.
Another advantage of my arrangement lies in the fact that a constant load is maintained on the source of energy during both the radiating and non-radiating periods.
Still another advantage of my arrange ment is that a relatively small current is broken by the key 13 during a signaling operation, thereby reducing the sparking at the contacts of the key to a minimum value.
Still a further advantage of my arrangement is the provision of a controlling circuit permitting a capacitance to be connected in shunt relation to a key to cause a still further reduction in the sparking at the contacts thereof.
While I have shown a specific type of arcgenerator in the transmission system embodying my invention it is apparent that various modifications in the arrangement of the anodes with respect to the cathode may be employed without departing from the spirit of my invention. I desire, therefore. that only such limitations shall be imposed thereon as are indicated in the appended claims.
I claim as my invention:
1. The method of arc signaling which consists in selectively supplying energy either to an oscillatory circuit or to a non-oscillatory circuit while maintaining uninterrupted operation of the arc.
2. The method of arc signaling which consists in selectively transferring an are from an anode connected to an oscillatory circuit to a second anode connected to a non-oscillatory circuit to control the radiation of energy from said oscillatory circuit.
In a system of signaling, the method of selectively transferring an are from an anode connected to an oscillatory circuit to a second anode connected to a non-oscillatory circuit which consists in varying the resistance of the non-oscillatory circuit.
4. In an arc generator, a pair of anodes, a cathode, a radiating circuit connected in shunt relation to one of said pair of anodes and said cathode and a supply circuit so con nected to said pair of anodes and said cathode that the idle anode is at a relatively higher voltage than the working anode, whereby the arc may be transferred more readily from one anode to the other.
5. In an arc generator, a pair of anodes, a cathode, a radiating circuit connected in shunt relation to one of said pair of anodes and said cathode and means for transferring the are from one of said anodes to the other.
6. An arc-system for radio signaling comprising two electrodes between which an arc is formed, a radiating circuit connected in shunt relation thereto, a third electrode and means whereby the arc may be transferred from one of said pair of electrodes to said third electrode.
7. An arc-system for radio signaling comprising two electrodes between which an arc is formed, a radiating circuit connected in shunt relation thereto, a third electrode and means whereby the arc may be transferred from one of said pair of electrodes to said third electrode to selectively control the flow of energy in the radiating circuit.
8. An arc-system for radio signaling comprising a pair of electrodes between which an arc is formed, a circuit for supplying energy to said are, and a radiating circuit, both in parallel and shunted around said pair of electrodes, a third electrode and means whereby the arc may be transferred from one of said pair of electrodesto said third electrode to control the flow of current in the radiating circuit.
9. An arc-system for radio signaling comprising a pair of electrodes between between which an arc is formed, a circuit for supplying energy to said are, said cir cuit including a resistor and an inductor and a radiating circuit both in parallel and shunted around said pair of electrodes, a
said trol the flow of current in the radiating circuit. 7
10. An arc-system for radio signaling comprising two electrodes between which.
an arc is formed, a radiating circuit connected in shunt relation thereto, a third electrode and key-controlled means whereby the arc may be transferred from one of pair of electrodes to said third electrode.
' 11. An arc system for radio signaling comprising a pair of electrodes between which an arc is formed, a third electrode, a circuit for supplying energy to said pair of electrodes, said circuit containingan inductor and a resistor, and a radiating system both in parallel and shunted around said pair of electrodes, and a circuit to which the arc may be transferred, said circuit containing said third electrode, one of said first-named pair of electrodes, a resistor, a key, a portion of said first-named resistor, a translating device and an inductor.
12. An are system for radio signaling comprising a pair of electrodes between which an arc is formed, a third electrode, a circuit for supplying energy to said pair of electrodes, said circuit containing an inductor and a resistor, and a radiating system both in parallel and shunted around said pair of electrodes, and a circuit to which the arc may be transferred, said circuit containing said third electrode, one of said firstnamed pair of electrodes, an inductor, aresistor, the resistance of which is substantially equal to the total antenna resistance, a key, a portion of said first-named resistor and a translating device.
13. An arc-system for radio signaling comprising a pair of electrodes between which an arc is formed, a third electrode, a circuit for supplying energy to said pair of electrodes, said circuit containing an inductor, a resistor and a translating device connected in serie relation, and a radiating system both in parallel and shunted around said pair of electrodes, and a circuit to which the arc may be transferred, said circuit containing said third electrode, one'of said first-named pair of electrodes, a resistor, a key, a portion of said first-named resistor and a translating device.
14:. An arc-system for radio signaling comprising a pair of electrodes between which an arc is formed, a third electrode, a circuit for supplying energy to said pair of electrodes, said circuit containing an inductor, a resistor and a translating device, and a radiating system both in parallel and shunted around said pair of electrodes, and a circuit to which the arc may be transferred, said circuit having connected in series relation said third electrode, one of said pair of electrodes, a resistor, a key, a portion of said first-named resistor and a translating device.
15. An arc-system for radio signaling comprising a pair of electrodes between Whlch an arc is formed, 'a third electrode, a
circuit for supplying energy to said pair of electrodes, said circuit containing an inductor, a resistor and a translating device, and a radiating system both in parallel and shunted around said pair of electrodes, and
a circuit to which the arc may be transferred, said circuit containing said third electrode, one of said pair of electrodes which serves as cathode, a resistor, a key, a portion of said first-named resistor and a translating device.
16. The method of signaling which consists in selectively changing the condition of an arc stream from an oscillatory state to a non-oscillatory state while'maintaining the continuity of said are stream.
17. The method of signaling which consists in selectively causing an arc to energize an oscillatory circuit and a non-oscillatory circuit while continuously maintaining the continuity of the arc tream.
18. The method of signaling which consists in selectively changing the condition ofan arc stream from an oscillatory state to a non-oscillatory state, maintaining the continuity of said are stream during said change and further maintaining the load on the source of supply substantially constant.
19. The method of signaling which consists in impressing upon an idle anode connected to a substantially n0nOscillatOry circuit a relatively higher voltage than that upon a working anode connected toa nonoscillatory circuit to transfer the are from the one anode to the other.
20. In an arc generator, a cathode element, a pair of normally stationary anode elements co-operating therewith and means for transferring an are between said elements from one anode to the other. I
21. In an arc generator, a cathode element, a pair of normally stationary anode elements co-operating therewith and means for transferring an arc between said elements from one anode to the other while maintaining the continuity of the arc.
22. In combination, an arc generator comprising a pair of anode elements and a cooperating cathode, means for establishing an are between one of said anode elements and said cathode, means for causing said ar to assume an oscillatory condition, means for transferring said are from the operating anode element to the non-operating anode element and means for changing the operat ing condition of e arc.
23; In ombination, an arc generator comprising a pair of anode elements and a cooperating cathode, means for establishing an arc-betweenone of said anode element and said cathode, means for causing said are to assume an oscillatory state and means for 5 transferring said are from the operating anode element to the idle anode element while maintaining the continuity of the arc,
said last mentioned means including means for changing the are from an oscillatory state to a non-oscillatory state. 10 In testimony whereof, I have hereunto subscribed my name this 30th day of November 1920. w
' QUINCY A. BRACKETT.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4547636A (en) * 1982-07-28 1985-10-15 Kabushiki Kaisha Tokai-Rika-Denki-Seisakusho Slidable contact assembly

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US4547636A (en) * 1982-07-28 1985-10-15 Kabushiki Kaisha Tokai-Rika-Denki-Seisakusho Slidable contact assembly

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