US1367735A - Amos f - Google Patents

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US1367735A
US1367735A US1367735DA US1367735A US 1367735 A US1367735 A US 1367735A US 1367735D A US1367735D A US 1367735DA US 1367735 A US1367735 A US 1367735A
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distributer
pole
line
impulses
changers
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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

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  • This invention relates to printing telegraph systems, and more particularly it relates to a transmitting system of the type wherein selecting switch mechanism whose function it is to determine the character of impulses to be transmitted. cooperates with a distributing mechanism, which determines the order of transmission of such impulses, to send out various permutations of signaling impulses to operate suitable printing mechanism at another station.
  • the invention is of particular utility in what is known as single channel operation, as distinguished from multiplex operation.
  • each transmitting set has control of the line for a quarter of the time only. After one transmitting set has. therefore, sent its train of impulses to the line, there remains suflicient time before the line again comes within the control of that set, to readjust the selecting switch mechanism for the sending of a new train of impulses.
  • single channel operation no such time interval is available and it becomes necessary, in order that the line may be operated at maximum efficiency, that some means he provided for permitting the readjustment of the transmitting set for a new train of impulses before the preceding train has been fully transmitted. In other words, some form of overlap is necessary.
  • Such an arrangement is provided by the present invention.
  • relays are alternately placed under the control of and locked against control by the selecting switches through a suitable arrangement of contacts on the transmitting (listributen whereby the various operations are properly timed to effect the desired result.
  • this invention makes use of an improved adaptation of the synchronizing system disclosed in my application Serial No.'869,784, filed November 2, 1914, and issued as Patent No. 1,280,423, Oct. 1, 1918.
  • This synchronizing system provides that the polarities of the marking and spacing impulses shall be reversed with each successive transmission of a train of impulses.
  • the markingimpulses are of positive polarity and the spacing impulses are of negative polarity
  • the marking impulses will be of negative polarity and the spacing impulses of positive polarity.
  • Such an arrangement is of advantage during such period as the transmitting apparatus may be running idle.
  • spacing impulses alone are sent to the line. If these impulses are of alternating polarity a means is available for maintaining synchronism between the transmitter and receiving distributers at all times.
  • the transmitting distributer employed is of the rotary type and has two sets of transmitting segments, both sets, however. being arranged to transmit the impulses set up by a single set of selecting switches.
  • the overlap relays above mentioned have under their control two sets of pole-changcrs, one set being connected to one set of transmitting segments of the distributor and and the other set being connected to the other set of transmitting segments of the distributor, and each relay having control of one pole-changer of each set.
  • One Set of pole-changers is normally arranged to send negative impulses to the line and to the other set is normally arranged to send positive impulses to the line.
  • any overlap relay When any overlap relay is a tuated it reverses the polarity of both of the pole-changer switches under its control and will, therefore, functionto send to the line an impulse of a polarity opposite to that of the spacing impulse, regardless of whether the brush arm of the distributor is traveling over one set of distributer contacts or over the other set of distributor contacts.
  • pole-changers 13, 1 1, 15, 16 and 17 are normally in position tosend negative impulses to the line, while the polechangers 28, 29, 30,31 and 32 are normally 1n positlon to send positive impulses to the Each of these polechangers reverses controlling it is operated.
  • relay 50 This causes relay 50 to operate, thereby closing" contact 51 and completing a circuit from grounded battery '52, by way of wire 53, contact 39 of switch 5, winding 5 10f relay 10 to ground.
  • Relay 10 operates, putting positive potential on segment 25, through the actuation of polechanger contact 15.
  • relay 50 will be deenergized, closing contact 56 and completing a holding circuit from battery 52 over wire 57 through the operated contact 58-of relay 10 and holding winding 60 to ground. Simultaneouslywith the operation of.
  • relay 10 relay 1-2 wil' have been operated by current from ground ed battery'52 by of contact 51, wire 53, contact 10, winding 61, to ground, and will have locked up simultaneously with relay 10 through the closureot the contact 56 upon the deenergization of relay 50: .Asthe brush 41.2 moves on to the segment 2% a negative impulse will be sent to line from the polechanger 1 1, inasmuch as the switch 4, and consequently relay 9 has not beenoperatcd As the brush 42 reaches segment 25 a posi tive impulse will be sent to the line, due to the fact that, as we have already seen, polechanger 15 has been operated by the energization of relay 10.
  • VVhilethe segments 62 and 65 which control the resetting of the transmitter are here placed so as to causethis resetting at the time the fourth impulse is being transmitted to the line, it is, of course, evident that this resetting need not take place exactly in coincidence with the transmission of the fourth impulse, the only requirement being that the resetting take place a sufiic'ient time ahead oi the transmission of the fifth impulse to insure that the transmitter is reset before the brush 21 moves on to the first segment of the next succeeding series that is, segment 33 01 23; the case may be.
  • a switch 66 is shown for disconnecting the line 44 from the transmitting distributer bar 43 and connecting it to ground for receiving purposes.
  • the receiving apparatus is indicated at 67 and the receiving segments and brushes of the distributer at 68. This receivin arrangement will not be described further, Inasmuch as it is the subject of another application.
  • a printing telegraph system a plurality of electromagnets, a pole-changer individual to each of said electromagnets, a distributer for successively connecting said pole-changers to the line, selective switching mechanism comprising a plurality of switch members for preparing circuits to said electromagnets, and means under the control of said distributer for closing said circuits.
  • a printing telegraph system a plurality of pole-changers, a distributer for successively connecting said pole-changers to the line, selective switch mechanism comprising a plurality of switch members, and means under the joint control of said distributer and said switch mechanism for selectively operating said pole-changers.
  • a plurality of pole-changers a distributer for successively connecting said pole-changers to the line
  • selective switch mechanism comprising a plurality of switch members, and means under the joint control of said distributer and said switch mechanism for selectively operating said pole-changers, and locking said operated pole-changers in their operated positions.
  • a series of selecting switches an electromagnet individual to each of said switches and selectively responsive to the actuation thereof, a pole-changer under the control of each of said electromagnets, a distributer for successively connecting said pole-changers to the line, and means under the control of said distributer for releasing said selecting switches for a new selection before the preceding set of impulses selected thereby has been fully transmitted.
  • a series of selecting switches an electromagnet under the control of each of said switches, a pole-changer individual to each of said electromagnets and operable thereby to determine the character of impulses to be transmitted, a distributer for successively connecting said pole-changers to the line, and means under the control of said distributer for completing the circuit of certain of said electromagnets.
  • a distributer having two sets of switch contacts, a set of pole changers for each set of switch contacts, and switching means simultaneously controlling the operation of predetermined ones of both sets of pole changers.
  • a 1'0- tary distributer having a plurality of groups of transmitting segments, a set of polechangers individual to each group, and a common switching mechanism for selectively operating corresponding polechangers of said sets simultaneously.
  • a distributer having a plurality of groups of transmitting switch contacts, a set of pole changers for each of said groups, and a set of electromagnets for selectively operating predetermined pole-changers of both sets simultaneously.
  • a rotary distributer having two groups of transmitting segments, a set of pole-changers for each of said groups, a set of electromagnets for controlling pole-changers of both sets simultaneously, and switching mechanism for selectively operating said electro-magnets.
  • a distributer having two groups of transmitting contacts, a set of pole-changers for each of said groups and normally arranged to impress opposite polarities on their respective groups, and means common to both sets of pole-changers for selectively and simultaneously reversing predetermined pole-changers of said sets.
  • a distributer adapted to transmit a series of impulses to a line and having a plurality of contacts, means for putting potential on selected contacts.
  • a switching mechanism for actuating said means, means under the control of the distributer and the switching means for looking said means, and other means under the control of the distributer for releasing said mechanism for a new operation before all the pulses of a series have been transmitted to the line by the distributer.
  • a distributer adapted to transmit a series of pulses-to a line and having a plurality of: contacts, aplurality of magnets for putting potential on selected contacts, a plurality of selective switching keys for actuating said magnets, means under the control of the distributer and the switching keys for locking certain of said magnets, and other means under the control of the distributer for releasing said switching keys for a new operation before all the pulses of a series have been transmitted to the line by the distributer.
  • the combination of distributer adapted; to transmit a series of pulses to a line. andhaving a plurality of'contacts, a plurality of mag-nets for putting potential on selected contacts, a plurality of selective switching keys for actuating said magnets, means under the control. of the distributer and. the switching keys for locking certain of said magnets, and a release magnet adapted tobe operated by said distributer at a predetermined moment to release said switching 'l'reys for anew operation before all: the 'pulsesof the series have been transmitted to the line by the distributer.

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  • Computer Networks & Wireless Communication (AREA)
  • Signal Processing (AREA)
  • Keying Circuit Devices (AREA)

Description

A. F. DIXON.
PRINTING TELEGRAPH SYSTEM.
APPLICATION FILED AUG. 1, I917.
Patented Feb. 8, 1921.
w TY 1 M UNITED STATES PATENT OFFICE.
AMOS F. DIXON, OF NEWARK, NEW JERSEY. ASSIGNOR TO WESTERN ELECTRIC CO!- PANY, INCORPORATED, OF NEW YORK, N. Y., A CORPORATION OF NEW YORK.
PRINTING-TELEGRAPH SYSTEM.
Specification of Letters Patent.
Patented Feb. 8, 1921.
Application filed August 1, 1917. Serial No. 183,891.
To all whom it may concern:
Be it known that I, AMos F. Drxox, a citizen of the United States, residing at Newark, in the county of Essex and State of New Jersey, have invented certain new and useful Improvements in Printlug-Telegraph Systems, of which the following is a full, clear, concise. and exact description.
This invention relates to printing telegraph systems, and more particularly it relates to a transmitting system of the type wherein selecting switch mechanism whose function it is to determine the character of impulses to be transmitted. cooperates with a distributing mechanism, which determines the order of transmission of such impulses, to send out various permutations of signaling impulses to operate suitable printing mechanism at another station.
The invention is of particular utility in what is known as single channel operation, as distinguished from multiplex operation. In quadruplex operation, for example, each transmitting set has control of the line for a quarter of the time only. After one transmitting set has. therefore, sent its train of impulses to the line, there remains suflicient time before the line again comes within the control of that set, to readjust the selecting switch mechanism for the sending of a new train of impulses. In single channel operation, however, no such time interval is available and it becomes necessary, in order that the line may be operated at maximum efficiency, that some means he provided for permitting the readjustment of the transmitting set for a new train of impulses before the preceding train has been fully transmitted. In other words, some form of overlap is necessary. Such an arrangement is provided by the present invention.
Between the selecting switch mechanism, which determines the character of impulses to be transmitted. and the transmitting distributer, which determines the order of transmission of these impulses, there is inserted ,a series of overlap relays whose function it is to store up the signal selected by the sele'ting switches and permit the readjustment of the selecting switches for a new selection before the transmission of the preceding signal has been completed.
These relays are alternately placed under the control of and locked against control by the selecting switches through a suitable arrangement of contacts on the transmitting (listributen whereby the various operations are properly timed to effect the desired result.
In combination with the above feature, this invention makes use of an improved adaptation of the synchronizing system disclosed in my application Serial No.'869,784, filed November 2, 1914, and issued as Patent No. 1,280,423, Oct. 1, 1918. This synchronizing system provides that the polarities of the marking and spacing impulses shall be reversed with each successive transmission of a train of impulses. In other words, if in the first tran of impulses the markingimpulses are of positive polarity and the spacing impulses are of negative polarity, in the next succeeding train of impulses the marking impulses will be of negative polarity and the spacing impulses of positive polarity. Such an arrangement is of advantage during such period as the transmitting apparatus may be running idle. During such pcriod spacing impulses alone are sent to the line. If these impulses are of alternating polarity a means is available for maintaining synchronism between the transmitter and receiving distributers at all times.
In the partimlar arrangement herein described, the transmitting distributer employed is of the rotary type and has two sets of transmitting segments, both sets, however. being arranged to transmit the impulses set up by a single set of selecting switches. The overlap relays above mentioned have under their control two sets of pole-changcrs, one set being connected to one set of transmitting segments of the distributor and and the other set being connected to the other set of transmitting segments of the distributor, and each relay having control of one pole-changer of each set. One Set of pole-changers is normally arranged to send negative impulses to the line and to the other set is normally arranged to send positive impulses to the line. When any overlap relay is a tuated it reverses the polarity of both of the pole-changer switches under its control and will, therefore, functionto send to the line an impulse of a polarity opposite to that of the spacing impulse, regardless of whether the brush arm of the distributor is traveling over one set of distributer contacts or over the other set of distributor contacts.
The invention will be more clearly understood by reference to the accompanying drawing, in which the contacts of a rotary tape;
' line.
the polarity sent to the line when the relay 7 distributer are shown in extended form at 2. 3, 1, 5, 6 and 7 represent the selecting switches commonly associated with an automatic transmitter operated by perforated Associated with these selecting switches are the overlap relays 8, 9, 10, 11 and 12 whose circuits are respectively under the control of the selecting switches 3, 4t, 6 and 7. These relays have under their control two sets of pole-changers, one set 13, 1 1, 15, 16 and 17 being connected to the transmitting segments 23, 2 1, 25, 26 and 27 on one-half of the distributer face, and the other set 28, 29, 30, 31 and 32 being connected'to the segments 34, 35, 36 and 37 on the other half of the distributer. It will be noted that the pole-changers 13, 1 1, 15, 16 and 17 are normally in position tosend negative impulses to the line, while the polechangers 28, 29, 30,31 and 32 are normally 1n positlon to send positive impulses to the Each of these polechangers reverses controlling it is operated.
To more clearly understand the operation of the system, let us consider that a series of impulses corresponding to the let ter Y is to be trai'ismitted, In this case switches 3, 5 and 7 will be actuated and their respective contacts 38, 39 and 40 will be closed. The closure of contact 38 closes circuit from grounded battery 11, through relay 8, to ground, thereby operating both of the pole-changers 13 and 23. As the distributer'b'rush 42 travels over segment 23 a positive impulse from the pole-changer 13 will be transmitted by way of the bar 43 to line 44. When brush 42 is in position on segment 23. brush 15' will close the circuit from grounded battery 46, by way of bar 17 to segment 48, thence by way of wire 19 to relay 50, and ground. This causes relay 50 to operate, thereby closing" contact 51 and completing a circuit from grounded battery '52, by way of wire 53, contact 39 of switch 5, winding 5 10f relay 10 to ground. Relay 10 operates, putting positive potential on segment 25, through the actuation of polechanger contact 15. As the brush arms 42 and 45 leave their respective segments 23 and 48 relay 50 will be deenergized, closing contact 56 and completing a holding circuit from battery 52 over wire 57 through the operated contact 58-of relay 10 and holding winding 60 to ground. Simultaneouslywith the operation of. relay 10, relay 1-2 wil' have been operated by current from ground ed battery'52 by of contact 51, wire 53, contact 10, winding 61, to ground, and will have locked up simultaneously with relay 10 through the closureot the contact 56 upon the deenergization of relay 50: .Asthe brush 41.2 moves on to the segment 2% a negative impulse will be sent to line from the polechanger 1 1, inasmuch as the switch 4, and consequently relay 9 has not beenoperatcd As the brush 42 reaches segment 25 a posi tive impulse will be sent to the line, due to the fact that, as we have already seen, polechanger 15 has been operated by the energization of relay 10. As the brush 42 reaches segment 26 the negative impulses will be sent to line, due to the fact that switch 6 and relay 11 have not been operated. At this time, however, brush 15 will connect battery 16 to segment 62, causing the energization of the transmitter ma net 63, whose function it is to move the transmitting tape along one step in order to pre sent a new row of perforations to the select ing fingers (not shown) which act in the well-known way to control the contacts of the switches'l, 1, 5, 6 and 7. The setting up of a new selection on the selecting switches does not, however, affect the impulses being sent out by segment 26', nor the one to be sent out by segment 27, inasmuch as the relays 10, 11 and 12, in so far as they have beenactuated, are locked in their actuated positions. Thus, when the'b'rush 42 reaches segment 27 a positive impulse will be sent to the line from the pole-changer 17. The brushes 42, 15 now move on the second set of transmitting segments, and if we are to consider that the same letter Y is to be repeated, itwill be seen that as brush 12 moves on to segment 33, a negative impulse will be sent to the line from the pole-changer 28 that as the brush reaches segment 34 a positive impulse will be sent to the line'from pole-changer 29; at 35 a negative impulse will be sent to the line from pole-changer 30; at 36 a positive impulse from polechanger 21 and at 37 a i'iegative impulse from pole-changer 32. The preparation of the circuit for therela'ys 10, 11 and 12 upon the transmission of the first impulse of the series occurs when brush 15 passes over seg 'ment 64, and the operation of' the transmitter magnet 63' occurs when the brush l-5 passes 0 er segment 65 in a manner similar to that described in connection with the first set of transmitter segments. VVhilethe segments 62 and 65 which control the resetting of the transmitter are here placed so as to causethis resetting at the time the fourth impulse is being transmitted to the line, it is, of course, evident that this resetting need not take place exactly in coincidence with the transmission of the fourth impulse, the only requirement being that the resetting take place a sufiic'ient time ahead oi the transmission of the fifth impulse to insure that the transmitter is reset before the brush 21 moves on to the first segment of the next succeeding series that is, segment 33 01 23; the case may be. No locking windin s have been provided for the relays 8 and 9, inasmuch as it has been found advisable to arrange that these relays be operated immediately upon the selection of their respective switches 3 and 4, to prevent the possible mutilation of signals due to lag of relay 50, and furthermore it has been found that suflicient time is available during the transmission of the third, fourth and fifth impulse for the complete resetting of the transmitter.
In the drawing a switch 66 is shown for disconnecting the line 44 from the transmitting distributer bar 43 and connecting it to ground for receiving purposes. The receiving apparatus is indicated at 67 and the receiving segments and brushes of the distributer at 68. This receivin arrangement will not be described further, Inasmuch as it is the subject of another application.
What is claimed is:
1. In a printing telegraph system, a plurality of electromagnets, a pole-changer individual to each of said electromagnets, a distributer for successively connecting said pole-changers to the line, selective switching mechanism comprising a plurality of switch members for preparing circuits to said electromagnets, and means under the control of said distributer for closing said circuits.
2. In a printing telegraph system, a plurality of pole-changers, a distributer for successively connecting said pole-changers to the line, selective switch mechanism comprising a plurality of switch members, and means under the joint control of said distributer and said switch mechanism for selectively operating said pole-changers.
3. In a printing telegraph system, a plurality of pole-changers, a distributer for successively connecting said pole-changers to the line, selective switch mechanism comprising a plurality of switch members, and means under the joint control of said distributer and said switch mechanism for selectively operating said pole-changers, and locking said operated pole-changers in their operated positions.
4. In a printing telegraph system, a series of selecting switches, an electromagnet individual to each of said switches and selectively responsive to the actuation thereof, a pole-changer under the control of each of said electromagnets, a distributer for successively connecting said pole-changers to the line, and means under the control of said distributer for releasing said selecting switches for a new selection before the preceding set of impulses selected thereby has been fully transmitted.
5. In a printing telegraph system, a series of selecting switches, an electromagnet under the control of each of said switches, a pole-changer individual to each of said electromagnets and operable thereby to determine the character of impulses to be transmitted, a distributer for successively connecting said pole-changers to the line, and means under the control of said distributer for completing the circuit of certain of said electromagnets.
6. In a printing telegraph system, a series of selecting switches, a grou of pole-changers selectively operable there y, a distributer for successively connecting said pole-changer to the line, and means under the control of said distributer for locking certain of said pole-changers in their selected position.
7. In a printing telegraph system, a distributer having two sets of switch contacts, a set of pole changers for each set of switch contacts, and switching means simultaneously controlling the operation of predetermined ones of both sets of pole changers.
8. In a printing telegraph system, a 1'0- tary distributer having a plurality of groups of transmitting segments, a set of polechangers individual to each group, and a common switching mechanism for selectively operating corresponding polechangers of said sets simultaneously.
9. In a printing telegraph system, a distributer having a plurality of groups of transmitting switch contacts, a set of pole changers for each of said groups, and a set of electromagnets for selectively operating predetermined pole-changers of both sets simultaneously.
10. In a printing telegraph system, a rotary distributer having two groups of transmitting segments, a set of pole-changers for each of said groups, a set of electromagnets for controlling pole-changers of both sets simultaneously, and switching mechanism for selectively operating said electro-magnets.
11. In a printing telegraph system, a distributer having two groups of transmitting contacts, a set of pole-changers for each of said groups and normally arranged to impress opposite polarities on their respective groups, and means common to both sets of pole-changers for selectively and simultaneously reversing predetermined pole-changers of said sets.
12. In a printing telegraph system, the combination of a distributer adapted to transmit a series of impulses to a line and having a plurality of contacts, means for putting potential on selected contacts. a switching mechanism for actuating said means, means under the control of the distributer and the switching means for looking said means, and other means under the control of the distributer for releasing said mechanism for a new operation before all the pulses of a series have been transmitted to the line by the distributer.
13. In a printing telegraph system, the combination of a distributer adapted to transmit a series of pulses-to a line and having a plurality of: contacts, aplurality of magnets for putting potential on selected contacts, a plurality of selective switching keys for actuating said magnets, means under the control of the distributer and the switching keys for locking certain of said magnets, and other means under the control of the distributer for releasing said switching keys for a new operation before all the pulses of a series have been transmitted to the line by the distributer.
14:. In a printing; telegraph system, the
v combination of a distributer adapted to transmit a series-of pulses to a line and haw ing a pluralityof contacts, a plurality of magnets for putting potential: on selected contacts, a plurality of selective switching keys for actuating, said magnets, a locking magnet in circuit with and adapted to be energized by the distributer to lock up cer tain of said magnets, themagnets locked up being dependent upon the selective operation of the distributer and the: switching keys, and other means under the control of the distributer for releasing said switching keys for a new operation before all the pulses of a series ha-vabeen transmitted to the line by the distributer.
15; In a printing telegraph system, the combination of distributer adapted; to transmit a series of pulses to a line. andhaving a plurality of'contacts, a plurality of mag-nets for putting potential on selected contacts, a plurality of selective switching keys for actuating said magnets, means under the control. of the distributer and. the switching keys for locking certain of said magnets, and a release magnet adapted tobe operated by said distributer at a predetermined moment to release said switching 'l'reys for anew operation before all: the 'pulsesof the series have been transmitted to the line by the distributer.
In witness whereof I hereunto subscribe my name. this. 30th day of July, A.v D; 1917.
AMOS F. DIXON.
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Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3472955A (en) * 1966-02-08 1969-10-14 Int Standard Electric Corp Telegraph apparatus having intermediate storage capability

Cited By (1)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3472955A (en) * 1966-02-08 1969-10-14 Int Standard Electric Corp Telegraph apparatus having intermediate storage capability

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