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US1472453A - Printing telegraphy - Google Patents

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US1472453A
US1472453A US352875A US35287520A US1472453A US 1472453 A US1472453 A US 1472453A US 352875 A US352875 A US 352875A US 35287520 A US35287520 A US 35287520A US 1472453 A US1472453 A US 1472453A
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magnet
arm
printing
selecting
impulses
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US352875A
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John H Bell
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AT&T Corp
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Western Electric Co Inc
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    • HELECTRICITY
    • H04ELECTRIC COMMUNICATION TECHNIQUE
    • H04LTRANSMISSION OF DIGITAL INFORMATION, e.g. TELEGRAPHIC COMMUNICATION
    • H04L25/00Baseband systems
    • H04L25/38Synchronous or start-stop systems, e.g. for Baudot code
    • H04L25/40Transmitting circuits; Receiving circuits
    • H04L25/42Transmitting circuits; Receiving circuits using mechanical distributors

Definitions

  • ananas are JOHN ⁇ H. BELL, OF SOUTH ORANGE, NEW JERSEY, ASSIGrNOB,- T WESTERN ELECTRIC COMPANY, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION 0F NEW YORK.
  • This invention relates to printing telegraphy and more particularly to printing telegraph receivers in which the characters are printed in a continuous line.
  • An object of the invention is the provision of a telegraph receiver of the above character wherein there is provided means for effecting the printing of the characters of a message in an eicient and reliable manner.
  • Another object of the invention is to provide means whereby the impulses are adapted to be stored in aplurality of signal storing means which will be rendered effective alternately for causing the operation of the selecting mechanism controlling the operation of the printing means for printing the characters of a message in a continuous line.
  • the invention provides a distributor under the control of line current impulses for ap? plying the impulses as transmitted ove-r the line to a rst and second group of signal storing means for eii'ectively storing up the signal impulses.
  • the provisionl of a signal storing means of this sort thereby gives a complete overlap and prevents the wasting of line time in the transmission and distribution of such impulses.
  • a translator switch is also provided for consecutively clearing out the groups of signal storing means and applying the impulses as stored therein to a selecting mechanism for eiecting the operation thereof to energize a printing magnet which controls the application of a tape to the characters of a type wheel for the printing'of the characters of a message in a continuous line.
  • FIG. 1 is a diagrammatic representation of the apparatus employed, while Fig. 2 is a perspective showing one form of construction of a printer wherein the characters are adapted to be printed in a continuous line.
  • the drawing shows a distributor 6 having a rotatable arm 7 carrying a contact brush and which is electrically connected with the amature of the polarized relay 5.
  • This relay is connected to the line 4 which extends from a distant station atY which there is l0- cated suitable transmitting apparatus for the transmission of the various impulses representing the characters of a message.
  • This relay is of the polarized type and is adapted to operate in accordance with the current impulses impressed ⁇ upon the line.
  • the armature of this relay is normally connected with the negative terminal of the battery 9 and is thus connected with the winding of the start magnet 8 through the arm '4' of the distributor 6.
  • the magnet 8 is, however,
  • the distributor 6 There is associated withthe distributor 6 a plurality of groups of signal storing means as represented by the characters A and B respectively.
  • These groups of signal storing means preferably consist of a number of condensers arranged ingroups; each condenser being connected with a segment of the distributor' so that when the arm 7 sweeps over the various segments, the condensers will be charged according to the polarity of the current as applied thereto through the armature of relay 5, the arm 7 and contact brush of the distributor 6.
  • the groups of signal storing means are arranged so that as soon as a set of character impulses have been received and stored in one group of signal storing means, these same stored impulses may be released to etlect the operation of suitable selecting mechanism, while the next or succeeding set of character impulses are being received and stored in another group of sign'al storing means, thereby providing a complete overlap in the selection of the message character.
  • a discharge path for the various condensers is established through the segments and brushes of the translator switch 21.
  • This translator switch comprises a number of segmented rings C,
  • the segments of the several rings are of dierent lengths and there are special segments individual to each of the condensers enumerated above.
  • the circuit for effecting the energization of selecting magnet 27 extends from the vterminal'of the condenser 12, conductor 35, segment 36 of ring E, brush 24, segment 37 of .ring F and the winding of the selecting magnet 27 which will be energized inthe same mann'er as selecting magnet 26.
  • Other condensers are, in a like manner, adapted to be consecutively connected with the windings of each of the selecting magnets 28, 29 and 30 for effecting their operation. After the selecting magnets have thus been energized, a circuit is established including the winding ofprinting magnet 38. Let us assume, for the sake of clearness, that the armatures of the selecting magnets have all been moved from the positions shown in the drawing thereby xclosing their front contacts.
  • the energizing circuit of the magnet 38 thus extends from the source of battery 40 through the segment 41, brush 23, segment 42, front contact of magnet 26, front contact of magnet 27, segment 43, brush 24, segment 44, front contact of magnet 28, front contact of magnet 29, segment 45, brush 25, segment 46, front contact of magnet 30, and the winding of printing magnet 38 to ground.
  • the printing magnet 38 will thus be operated lto effect the printing of a desired character as will be more clearly brought out in the description which is to follow.
  • the 'armi 7 is adapted, after completing a half cycle to be held against rotation by means of the holding pawl controlled by magnet 50, the .energizing circuit of which is completed in the same manner as that of magnet 8. In this way the arm 22 will have ample time to completely clear out the signal storing means A before the initial impulse of the Second group of selecting impulses is received for effecting the operation of relay 5 and in consequence the energization of magnet 50 and the subsequent charging of the second set of condensers 16 to 20 inclusive, in accordance with the selecting impulses as transmitted over the line.
  • Relay 30 determines which one of these windings 51 o'r v52, will be energized as the round connection controlled thereby is ad.pted to be shifted from one contact to the other, depending upon ns energization. It is to be noted that the printing magnet 38 is unaffected atv this time, as certain ones of the'selectingmagnets will be so energized asto prevent the establishment of the energizing circuit for this magnet.
  • the segments to which the windings 5l and 52 of' relay 63 are connected are at the end of the travel of the translator arm 22 and are therefore not energized until this arm has nearly completed its cycle.
  • Fig. 2 there is shown one form of construction of a printer for effecting the printing of the characters of 'a message in a continuous line.
  • the arm 7 1 of the distributor 6 is frictionally connected with the shaft 53 which is driven from the motor i.
  • the arm 7 is adapted, as ⁇ heitere noted. to be held against rotation by means of holding pawls under the control of magnets 8 and 5U. it one extremity of the shaft 53 'there is keyed a gear 55 ⁇ which drives another gear or pinion such as 56. Both of these gears are so proportioned with respect to one another that the speed o the one will be twice that of the other.
  • the gear 5G is connected with a shaft 64 upon which is frictionally mounted the arm 22 of the translator switch 21 and the type shaft 57.
  • This arm 22 is held against rotation by means of the holding pawl controlled by magnet 31.
  • the magnet 3S has attached to its armature a striker bar or hammer 59 which serves to press the tape 60 against the type Wheel 58 upon the energization of this magnet.
  • Selecting impulses are thus stored in the condensers which may be rendered elfective for causing the operation of the selecting magnets.
  • the arm I has passed over the segment individual to the condenser 15 and makes contact- With segment 61, magnet 31 vill be energized over a circuit extending from battery through the winding ot magnet 31, segment 61, arm 7 and brush connected thereto to the negative source of battery controlled by the armature of relay 5.
  • This magnet 31 upon being energized attracts its armature and withdraws the holding pawl which holds the arm 22 against rotation.
  • the arm 7 will, atterpassing over the segment (51 through which the magnet 31 is connected, be held by the holding pawl controlled by magnet and will not be released until the initial impulse of the second group of selecting impulses is received at which time it will associate the various condensers in group B of the signal storing means with the armature of relay 5, in order that they may be charged in accordance With the incoming impulses.
  • the translator arm 22 in rotating, moves in the direction of the arrow and connects the condensers of group A with the Winding ofv each of the selecting magnets individual thereto.
  • the armatures of the selecting magnets are in their normally unactuated position and that the magnets tov which current of a negative polarity is applied will be energized so as to attract their armatures and close their front contacts.
  • the selecting ⁇ impulses stored in the set of condensers A will be consecutivelyT applied to the selecting relays 26, 27, 28, 29 and 30 through circuits previously traced.
  • a printing telegraph receiver com? prising a plurality of groups of signal storing means. a distributor for allotting current impulses to said signal storing means, selecting mechanism, a translator switch' for consecutively associating said signal storing means with said selecting mechanismtor eli'ecting the operation thereof, ⁇ and a printing magnet jointly controlled by said translator switch and said selecting mechanism for printing the characters of a message.
  • a system of printing telegraphy comprising a line, a relay responsive to current impulses transmitted over said line, current distributing means controlled by said relay, signal storing means associated with said distributing means, a plurality of selecting relays, a translator switch for translating the. effects of said signal storing means to said relays, a printing magnet, and an energizing circuit therefor completed through segments of said translator switchand contacts controlled by said selecting relays for causing the printing of a desii-ed character.

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  • Engineering & Computer Science (AREA)
  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Accessory Devices And Overall Control Thereof (AREA)

Description

Oct. 30 1923.
J" H. BELL PRINTING TELEGRAPHY Filed Jan. 20, 1920 by A wfy
Patented ct. SO, i923.
ananas are JOHN`H. BELL, OF SOUTH ORANGE, NEW JERSEY, ASSIGrNOB,- T WESTERN ELECTRIC COMPANY, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION 0F NEW YORK.
PRINTING TELEGRAPHY.
Application led January 20, 1920. Serial No. 352,875.
To all whom it may concern:
Be it known that I, JOHN H. BELL, a citizen of the United States, residing at South Grange, in the county of Essex, State of New Jersey, have invented certain new and useful Improvements in Printing Telegraphy, of which the following is a full, clear, concise, and exact description.
This invention relates to printing telegraphy and more particularly to printing telegraph receivers in which the characters are printed in a continuous line.
An object of the invention is the provision of a telegraph receiver of the above character wherein there is provided means for effecting the printing of the characters of a message in an eicient and reliable manner.
Another object of the invention is to provide means whereby the impulses are adapted to be stored in aplurality of signal storing means which will be rendered effective alternately for causing the operation of the selecting mechanism controlling the operation of the printing means for printing the characters of a message in a continuous line.
The invention provides a distributor under the control of line current impulses for ap? plying the impulses as transmitted ove-r the line to a rst and second group of signal storing means for eii'ectively storing up the signal impulses. The provisionl of a signal storing means of this sort thereby gives a complete overlap and prevents the wasting of line time in the transmission and distribution of such impulses. A translator switch is also provided for consecutively clearing out the groups of signal storing means and applying the impulses as stored therein to a selecting mechanism for eiecting the operation thereof to energize a printing magnet which controls the application of a tape to the characters of a type wheel for the printing'of the characters of a message in a continuous line.
In the accompanying draWing'Fig. 1 is a diagrammatic representation of the apparatus employed, while Fig. 2 is a perspective showing one form of construction of a printer wherein the characters are adapted to be printed in a continuous line.
The drawing shows a distributor 6 having a rotatable arm 7 carrying a contact brush and which is electrically connected with the amature of the polarized relay 5. This relay is connected to the line 4 which extends from a distant station atY which there is l0- cated suitable transmitting apparatus for the transmission of the various impulses representing the characters of a message. This relay is of the polarized type and is adapted to operate in accordance with the current impulses impressed` upon the line. The armature of this relay is normally connected with the negative terminal of the battery 9 and is thus connected with the winding of the start magnet 8 through the arm '4' of the distributor 6. The magnet 8 is, however,
prevented from operating since there is connected with the magnet winding a source of battery, the polarity of which is such as to oppose the flow of current from the battery 9.
There is associated withthe distributor 6 a plurality of groups of signal storing means as represented by the characters A and B respectively. These groups of signal storing means preferably consist of a number of condensers arranged ingroups; each condenser being connected with a segment of the distributor' so that when the arm 7 sweeps over the various segments, the condensers will be charged according to the polarity of the current as applied thereto through the armature of relay 5, the arm 7 and contact brush of the distributor 6. The groups of signal storing means are arranged so that as soon as a set of character impulses have been received and stored in one group of signal storing means, these same stored impulses may be released to etlect the operation of suitable selecting mechanism, while the next or succeeding set of character impulses are being received and stored in another group of sign'al storing means, thereby providing a complete overlap in the selection of the message character. A discharge path for the various condensers is established through the segments and brushes of the translator switch 21. This translator switch comprises a number of segmented rings C,
D, E. F, G and H, shown developed in Fig.
l. The segments of the several rings are of dierent lengths and there are special segments individual to each of the condensers enumerated above. A translator arm 22 carrying brushes 23, 24 and 25, each of which is individual to a pair of segmented rings Vis adapted to be moved in a manner which will be presently described for consecutively connecting the signal storing means with the ing means associated with the distributor,
it is necessary that the translator switch arm 22 complete two cycles to one of the arm 7 of the distributor 6. It is, therefore, ar-
ranged so that the magnet 31 will be energized subsequent to the chargin of the condensers of each of the groups of signal storing means for effecting the release of arm 22. It is thus seen that the translator switch arm 22 together with the brushes carried thereby will be caused to make two complete cycles to one of the arm 7 for clearing out the two groups of signal storing means connected with the segments of the distributor 6.
Let us assume that the arm 22 of the translator switch is moving in the direction of the arrow and that the condensers in group A of the signalstoring means have been charged in accordance with a group of selecting impulses as transmitted over the line 4. There will thus be completed a circuit including the winding of the selecting magnet 26 which may be traced from the terminal ofcondenser 11, conductor 32, segment 33 of ring Gr, brush 23, segment 34 of ring H and the winding of the selecting magnet 26 which will thusbe energized in accordance with the polarity of the charge on the condenser 11. The circuit for effecting the energization of selecting magnet 27 extends from the vterminal'of the condenser 12, conductor 35, segment 36 of ring E, brush 24, segment 37 of .ring F and the winding of the selecting magnet 27 which will be energized inthe same mann'er as selecting magnet 26. Other condensers are, in a like manner, adapted to be consecutively connected with the windings of each of the selecting magnets 28, 29 and 30 for effecting their operation. After the selecting magnets have thus been energized, a circuit is established including the winding ofprinting magnet 38. Let us assume, for the sake of clearness, that the armatures of the selecting magnets have all been moved from the positions shown in the drawing thereby xclosing their front contacts. The energizing circuit of the magnet 38 thus extends from the source of battery 40 through the segment 41, brush 23, segment 42, front contact of magnet 26, front contact of magnet 27, segment 43, brush 24, segment 44, front contact of magnet 28, front contact of magnet 29, segment 45, brush 25, segment 46, front contact of magnet 30, and the winding of printing magnet 38 to ground. The printing magnet 38 will thus be operated lto effect the printing of a desired character as will be more clearly brought out in the description which is to follow.
The 'armi 7 is adapted, after completing a half cycle to be held against rotation by means of the holding pawl controlled by magnet 50, the .energizing circuit of which is completed in the same manner as that of magnet 8. In this way the arm 22 will have ample time to completely clear out the signal storing means A before the initial impulse of the Second group of selecting impulses is received for effecting the operation of relay 5 and in consequence the energization of magnet 50 and the subsequent charging of the second set of condensers 16 to 20 inclusive, in accordance with the selecting impulses as transmitted over the line.
If it is desired to print an upper case letter, a special group of impulses will be transmitted over the line for causing the operation of relay 5 in accordance therewith and-the condensers 11 to 15 or 16 to 20, depending upon the position of arm 7 of the distributor 6, will be'charged accordingly. The shifting of type wheel 58 for performing such a function is 'controlled by magnets 47 and 48 which in turn are operated through the contacts of relay 63.- The energizing circuit for the windings 51 and 52 of this relay is adapted to be established through the segments of the various rings of thetranslator switch and the right-hand armature of relay 30. Relay 30 determines which one of these windings 51 o'r v52, will be energized as the round connection controlled thereby is ad.pted to be shifted from one contact to the other, depending upon ns energization. It is to be noted that the printing magnet 38 is unaffected atv this time, as certain ones of the'selectingmagnets will be so energized asto prevent the establishment of the energizing circuit for this magnet. The segments to which the windings 5l and 52 of' relay 63 are connected are at the end of the travel of the translator arm 22 and are therefore not energized until this arm has nearly completed its cycle.
No means has been shown or provided for advancing the tape because any well-known method of spacing or line feed can be provided and since this does not form a part of the present invention it has been omitted for the sake of clarifying the drawing and the description relativer thereto.
Referring now to Fig. 2 there is shown one form of construction of a printer for effecting the printing of the characters of 'a message in a continuous line. The arm 7 1 of the distributor 6 is frictionally connected with the shaft 53 which is driven from the motor i. The arm 7 is adapted, as `heitere noted. to be held against rotation by means of holding pawls under the control of magnets 8 and 5U. it one extremity of the shaft 53 'there is keyed a gear 55 `which drives another gear or pinion such as 56. Both of these gears are so proportioned with respect to one another that the speed o the one will be twice that of the other. The gear 5G is connected with a shaft 64 upon which is frictionally mounted the arm 22 of the translator switch 21 and the type shaft 57. This arm 22 is held against rotation by means of the holding pawl controlled by magnet 31. There is keyed to the shaft 5T the type Wheel 58 and, inasmuch as the rotation of this shaft -is under the control of the translator arm 22, the. type Wheel 58 will be rotated at a speed dependent upon the speed of the motor and the ratio of the gear reduction through which it is driven. n arrangement is shown in connectionwith the type Wheel 58 which is controlled by means of the magnets 47 and 48 for shifting the type wheel from a lower to an upper case` or vice versa. The magnet 3S has attached to its armature a striker bar or hammer 59 which serves to press the tape 60 against the type Wheel 58 upon the energization of this magnet.
A better understanding of the apparatus may be obtained from a description of the operation thereof and, .for the sake of clearness. let us assume that it is desired to transmit the character D. This character may be represented by the following group of impulses, positive7 negative, negative, positive and negative. It may also be assumed that there is a like distributor at the transmitting statione the same as that represened by the numeral 6 and which is adapted to rotate in synchronism therewith. A distant operator, in transmitting the letter D, would impress upon the line 4, a preliminary or initial impulse of a positive polarity which may be considered a starting impulse. This starting impulse thereby causes -the operation of relay 5 which connects through its armature, the source of battery 10 with the Winding of magnetl 8. The connection of this source of battery with the Winding ot magnet 8 thereby causes its operation as the sources of battery connected thereto are now in series aiding and current, therefore, ow through the winding of magnet 8. The energization of magnet 8 thereby causes the attraction of the holding pawl and releases the arm 7 which is rotated by the motor 5%. The contact arm 7 together with its brush in passing over the segments ot the distributor places a charge on the condensers 11 to 15 inclusive, dependent upon the source of the current connected therewith through the armature of relay 5. Condensers 12, 13 and l5 will thus be charged negatively, While the remainder of those in group A will be charged positively. Selecting impulses are thus stored in the condensers which may be rendered elfective for causing the operation of the selecting magnets. mmediately atter the arm I has passed over the segment individual to the condenser 15 and makes contact- With segment 61, magnet 31 vill be energized over a circuit extending from battery through the winding ot magnet 31, segment 61, arm 7 and brush connected thereto to the negative source of battery controlled by the armature of relay 5. This magnet 31 upon being energized attracts its armature and withdraws the holding pawl which holds the arm 22 against rotation. The arm 7 will, atterpassing over the segment (51 through which the magnet 31 is connected, be held by the holding pawl controlled by magnet and will not be released until the initial impulse of the second group of selecting impulses is received at which time it will associate the various condensers in group B of the signal storing means with the armature of relay 5, in order that they may be charged in accordance With the incoming impulses.
The translator arm 22 in rotating, moves in the direction of the arrow and connects the condensers of group A with the Winding ofv each of the selecting magnets individual thereto. Let us assume, for the sake of clearness, that the armatures of the selecting magnets are in their normally unactuated position and that the magnets tov which current of a negative polarity is applied will be energized so as to attract their armatures and close their front contacts. As the brush arm of the translator switch continues its rotation, the selecting` impulses stored in the set of condensers A will be consecutivelyT applied to the selecting relays 26, 27, 28, 29 and 30 through circuits previously traced. Inasmuch as these relays are of the polarized type and respond to close their front contact only upon the application thereto of a negative impulse, for the particular example selected, selecting magnets 27, 28 and 3() will be energized to close their front contacts. .Vith the armatures of these selecting magnets in this position and the continued rotation of the brush arm of the translator switch in the direction of the arrow, a circuit is completed upon the passing of the respective brushes over segments 41, 64, 65, 66, 67 and 68 Jfor causing the energization of the printing magnet 38.- Such a circuit may be traced from grounded battery 40 through; segment 41, brush 28, segment 64, back contact of magnet 26, front contact of magnet 2T, segment 65,. brush 2e, segment 66, front contact of magnet 28, back contact of magnet 29, segment 67, brush 25, segfir ment 68, front contact of magnet and the winding of printing magnet 38 to ground. When the translator brush arm is in this position, the character D, on the type wheel, which was desired to be printed, will now be in a position opposite the printing hammer 59 and inasmuch as the circuit or'tlie printing'inagnet is at this time completed as just described, an impression of the character D will be made on the tape GO. Blurring of the printed characters may be avoided by advancing the tape at the time of printing at a speed substantially equivalent to the speed of rotation of the type wheel as shown in Patent No. 388,244 to Baudot, August 2l, 1888. It is also to be noted that the arm 22 of the translator switch 2l will have passed over the first Jfour segments of the translator switch rings-before the arm 7 of the" y distributor G is released to complete its cycle l. A printing telegraph receiver com? prising a plurality of groups of signal storing means. a distributor for allotting current impulses to said signal storing means, selecting mechanism, a translator switch' for consecutively associating said signal storing means with said selecting mechanismtor eli'ecting the operation thereof, `and a printing magnet jointly controlled by said translator switch and said selecting mechanism for printing the characters of a message. v
Q. In combination a line, a relay asso ciated with said line and operated by permutations of current impulses, a distributor, a translator switch adapted to make two revolutions to one of said distributor, means operated byA said distributor for causing the operation of said translator switch, printing means, and a plurality of selecting magnets controlled by said translator switch and energized by current impulses as received by said distributor for effecting the printing of the characters of a. message in a continuous line.
A system of printing telegraphy comprising a line, a relay responsive to current impulses transmitted over said line, current distributing means controlled by said relay, signal storing means associated with said distributing means, a plurality of selecting relays, a translator switch for translating the. effects of said signal storing means to said relays, a printing magnet, and an energizing circuit therefor completed through segments of said translator switchand contacts controlled by said selecting relays for causing the printing of a desii-ed character.
In witness whereof, I hereunto subscrib my name this 16th day of January, A.. D.
' JOHN H. BELL.
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