US1530567A - Printing telegraphy - Google Patents

Printing telegraphy Download PDF

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US1530567A
US1530567A US432172A US43217220A US1530567A US 1530567 A US1530567 A US 1530567A US 432172 A US432172 A US 432172A US 43217220 A US43217220 A US 43217220A US 1530567 A US1530567 A US 1530567A
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Prior art keywords
relay
contact
armature
hand
magnet
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US432172A
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Alben E Lundell
Arthur B Sperry
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AT&T Corp
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Western Electric 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
    • H04M15/04Recording calls, or communications in printed, perforated or other permanent form

Definitions

  • An object of the present invention is the provision of a system wherein the opera tion of an automatic telephone" impulse sender or calling dial may be recorded by a receiving printer.
  • the locking circuit for the space locking relay 107 extends from battery 114, winding of spacing magnet 130, conductor 115, right-hand armature and contact of space locking relay 107. righthand winding of this relay, and the righthand normal contact and armature of relay 136 to ground.
  • the space magnet 130 attracts its arn'iature 13$), causing the stepping pawl attached thereto to engage the teeth of a ratchet wheel 137, advancing this wheel through the space of one tooth.
  • the carriage return magnet 196 is caused to release the holding pawl controlled thereby tor ctlccting the engagement thereof with the ratchet wheel 137, as the paper carriage is stepped forward for a line of print.
  • the energization of the line feed magnet also causes the operation of a suitable stepping pawl tor shifting the paper or other printing medium to a new line.

Description

' March 24, 1925. 1,530,567 I A. E. LUNDELL :ET AL.
PRINTING TELEQRAPHY Filed De. 21, 1920 2 She ets-Sheet 1 5!. 0 RELEASE: T
sum; RELEASE 4/52 E Zunde/Z I A/fvf March 24, 1925. 1,530,567
A. E. LUNDELL ET AL PRINTING TELEGRAPHY 21, 1920 2 Sheets-Sheet 2 Patented Mar. 2534i, 3925.
ALBEN n. LUNDELL' AND ARTHUR s. srnaasd, or new Yeas, N. Y., assionons TO WESTERN nnncrnrc cor/nearer, INCORPORATED, on NEW YORK, N. Y., A coasting more or NEW Yon-Ls.
a PRINTING TELEGRAPHY.
Application filed. December 21,1920, Serial No. 4:32am.
To oZZ whom it may concern:
Be it known that we, Amine: E. Lnnoanii and Airrnon l3. SPEND, citizens of the United States, residing at New York, in the county of Bronx and State of New York, and New York, in the county of New York and State oi New York, respectively,have invented certain new and useful Improvements in Printing 'l'elegrapliy, of which the following is a full, clear, concise, and exact description.
This invention relates to printing teleg raphy and particularly to a novel arrange ment for effecting the operation of a receiving printer.
An object of the present invention is the provision of a system wherein the opera tion of an automatic telephone" impulse sender or calling dial may be recorded by a receiving printer.
For accomplishing the above and other objects, the invention conten'iplates the provisiono't' a receiving printer in combination with an automatic telephone selector switch responsive to the operation of an impulse sender or calling dial for'selecting a combination of contacts in said switch whereby the printer mechanism is operated for recording the actuation of saidimpulse sender or calling dial. 7
In the accompanying drawings there is shown an arrangement of connections be tween an automatic selector switch and a receiving printer in a system embodying the principles of the present invention. In Fig. 1 there is illustrated an automatic sub-station A which is connected to a pair of line conductors to which there is connected a selector switch B. In'Fig. 2 a receiving printer is shown diagrannuatically and connected with the contacts on the selector switch B. The invention will be more clean 1y understood after considering the following description taken in conjunction with the accompanying drawings.
The sub-station A may he of any suitable common battery auton'ia tie type as shown in Fig. 1, which comprises the usual receiver 5,
'switchhook 38, transmitter 39,'ca'11"be1l 40, and condenser 41. Bein an autoin atic'substation it is also provide with impulse contact springs'S and'SJand an iinpu'lsewheel 7. The impulse wheel carries upon its periphery a number of teeth 'designedtof'engage a plunger for effecting the separation of contact springs 8 and 9. Attached to the'jmpulse wheel 7 is a dial (not sliown)x".with linger holes through the medium ofwhich the impulse wheel 7 may be revolved As the impulse wheel 7 is returned to normal position by a suitable spring "(not shown) contacts 8 and 9 will be broken. The numher of times which these contact springs are separated depends upon the distance through which the impulse wheel is rotated.
The selector switch B is of the general type of selector switch disclosed in 'UQS. Letters Patent No. 815,17 6 issued March 13,
1906 to Keith, Ericson and Erics'on. Like switch, while in theupper bank of terminals the brush 36 engages but one contactpfor each position of the switch. Associated with the selector switch B is the necessary apparatus, including relays and othermechanical mechanism for effecting theoperation of the switch, and since thispart ofthe system is well understood by thosesk illed in the art, a't'urther description thereofis considered unnecessary here.
lntcrconnecting the selector switch B and the receiving printer C is a plurality of conductors divided into two groups. Onegroup of these conductors connects the contacts of 'the respective bank of terminals with the The other group of conductors extends between additional apparatus common to the selector switch mechanism to the apparatus of the printer. A receiving printer of the I type adapted to be used for the present inzf, the right-hand armature, and alternate vention is disclosed and described in Patent- No. 1,113,033 issued to A. F. Dixon July let,
1914, and since this patent describes in detail such a receiving printer, and especially since the receiving-printer per se is not claimed in the present invention, only so much of the system has been shown as will afi'ord a clear understanding of the invention. Obviously, though, other types of receiving printers may be employed other than the one disclosed and claimed in the above referred'to patent.
A better understanding of the invention may be obtained from a description of the selection of a particular character and the operation of the system for such a selection Will therefore be traced in the following description. Assuming that the subscriber A desires to transmit the digit 4, the
impulse wheel 7 will thus berotated. Upon the return of the impulse wheel 7, contacts.
8 and 9 will be separated in accordance with the op ration of the impulse wheel 7. The subscri er A,'having already removed the receiver 5 from the switchhook, causes the operation of line relay 10, and consequently the slow to release relay 11. Each tune contact springs 8 and 9 are separated, line relay 1O deenergizes. Since relay 11 is of the slow to release type, it does not have suflicient time to deenergize during the momentary interruption of its circuit at the right-hand contact of line relay 10.
Consequently, the engagement ofthe arma ture of relay 10 with its normal contact establishes a circuit extending from battery through the vertical magnet 13, relay 12, leit-handarmature of relay l1, left-hand armature of relay 14, and the normal contact and armature of relay 10 to ground.
The vertical magnet 13 receives tour 1mpulses. over this circuit and operates to raise the vertical member 43 and brushes carried thereby four steps to a position opposite the fourth row of terminals in each of the contact banks. The relay 12 is energized in series with the vertical magnet 13, but be- -ing of the slow to release type, does not have sullicient time to deenergize upon the momentary interruption of its energizing cir .cuit at the contacts of line relay 10. Relay ].2 upon energizing closes a circuit from battery through the winding of relay 15 oii normal contact 33, lefthand contact and armature of relay 16, left-hand alternate contact of relay. 12; and the righthand alter- --nate contact of relay 1 1 to ground. The
. closure of thelefthand contact of re y 15 establishes a locking circuit for this slay which extends from battery through the winding of relay 15 off normal contact 33, left-hand contact and armature of relay 16, right-hand contact of relay 15, righthand normal contact of relay 16, conductor contact of relay 11 to ground. As a result of the establishment of this locking circuit, relay 15 remains energized after relay 12 releases its armature upon the cessation of the impulses transmitted for the fourth 7 digit. Upon the deenergization of relay 12 a circuit is established extending from battery through rotary oil-normal contact 38 winding of rotary i'nagnet 1c, right-hand contact and arn'iature of relay 15, normal contact of relay 12, and the right-hand contact of relay 11 to ground. The rotary magnet 16 upon energizing rotates the vertical shaft 43 together with the brushes carried thereby one step. The olf-normal contact. 38 which is shown normally closed. is opened following the rotation of the vertical shaft- 13 through a distance equal to one ,step. The rotary magnet: 16 is thereupon prevented from energizing folloi'ving its release and the consequent reenergization of. relay 15. By rotating the springs 35 and 36 contact is made with the contacts in the fourth level of each of the respective banks. The brush 36 like the brush 35 serves to select circuits as is described hereinafter for the operation of predetermined ones of the selecting relays and magnets of the printer mechanism shown in Fig. 2. Rotary magnet 16 in closingits left hand contact establishes an energizing circuit for relay 11 extending from battery through the Winding of relay 15, oti normal contact 33, left-hand contact and armature of relay 16, winding of relay 14, and the right-hand armature and contact of relay 11 to ground. Relay 14 in attracting its arn' atures opens at the right-hand contact thereof the originalcnergizing circuit for relay 12 and the vertical magnet 13 for preventing the false operation of these devices.
Upon the engagement of the brush 35 with contacts 45 and 46 a circuit extending through the left-hand winding of relays 122 and 124-. of the rinter mechanism is cstab- 11.1 lished. Normal y, current flows from battery 104, left-handnormal contact of clear out relay 1S0, conductor 106, and the right hand windings of relays 121, 122, 123. 124:, 125 and 128 to ground. The current passing 1:.0 through the windings of these relays is, how ever, insufficient to cause the initial operation thereof, but serves to assist the operating windings in pulling up the respective armatures, thereby increasing the rapidity of operation. After the relays have-once been operated, the current flowing from the batery 104 is suiiicient to hold the armaturcs in their actuated positions. The connection of the brush 35 with contacts 45 and .6 apmo plies to these terminals a ground connection,
and since battery is normally connected with the right-hand windings of relays 122 and 124, these relays will be operated over a circuit. extending from battery through the left-hand-winding thereof, and the conductors connecting with contacts 45 and 46 of the selector switch B, contact springs to ground at the normal contact of relay 19. The selector magnets 132 and 134 are connected in parallelrelation with the selecting relays 122 and 124, and will thus be energized over the same circuit as traced for relays 122 and 124-. Normally, current flows from battery 104 thro1igh the right-hand normal contact of clear out relay 180, holding windings of release magnets 178 and 179, right-hand winding of type selecting magnets 131, 132, 133, 134 and 135, as previously described in connection with the selecting relays, this current is insufi'icient to. initially operate the magnets, but will however rc-; tain them actuated after the original operating circuit is severed. Selecting relays 121, 123 and 125 will not be operated at this -time, a circuit including thewindings of produced on the printer circuits.
these relays is not established upon the en gagement of the brush 35 with the contacts 'and 46. In the upper bank of terminals of the selector switch B, the fourth level of contacts isnot c nnected. Thus, no eflfect is As hereinbefore described, a current normally flows through the right-hand windings ofthe selecting relays. Consequently, upon the ener gization of any one thereof, the armatures will be retained in their actuated positions irrespective of the disconnection of the original operating current. 1
Following the operation of relay 14, relay 18 is eiiergized over a circuit extending from battery throughthe winding of relay 15, off
normal contact 33, left-hand contact and armature of relay 16, left-hand contact and armatureof'relay 15, right-hand contact and armature of relay 16, winding of relay 18, winding of relay 19, right-hand armature and contact of relay 14, and the right-hand armaturc and contact of relay 11 to ground.
The attraction of the middle armature of relay 18 cstablishes acircuit extending from battery through the'shift magnet 170, conductor 24, middle armature and contact of relay 18, conductor 25, and contact 142 to ground. Shift magnet 170 upon energizing,
attracts its armature for shifting the type wheel from a lower to an upper case letter.
- In order that the type wliecl'will be retained in this position for a definite number of digits, :1 locking circuit, therefore, is estab lished upon its cn'ergization. This locking circuit extends from battery through the winding 01'' shift magnet 170, contact and armature thereof, and contact 142 to ground. Relay 18 in closing its left-hand contact conncctsa source of battery 47 to the letthand winding of start relay 126, and thcoperatin windings of release ma nets 17 8 and 17 9. 1
Start relay 126 and release magnets 178 and 179 are thereupon energized over a circuit extending from battery 47, left-hand contact and armature of relay 18, conductor 37, conductors 140 and 141 in. parallel, and the opcrating winding of relay 126and release magnets 178 and l'f'9rto ground. Release magnets 178 and 179 attract their armatures,
forcing the free ends thereof as described in the previously referred to patent, for allowing the selected type lever 165 to assun'ic a new position, the projecting end thereof being in alignment with the stop member 166. The stop member 166 is carried by the same shaft as the type wheel (not shown). Thus,
upon the engagement of this member with the projecting end of the lever 165, the type wheel will-be arrested. The operation oi the start relay 126 applies through its righthaud contact ground for effecting the oper,--'
ation of start magnet 194. The energizing circuit of the start magnet 194 extends from 1 battery 104, leithand armature and contact of clear-out relay 180, conductor 108, winch mg of start magnet 194, conductor 109,
winding of clear-out relay 180, left-hand winding of space locking relay 107, conductor 111, winding of, printing magnet 105, stop arm 166, selected type lever 165, conductor 23, and the armature and contact of relay 19 to ground. Printing magnet 'attracts its armature, forcing a printing hammer (not shown) against the paper, printiug the desired character.
The circuit just traced. through the winding of relay 180 causes this relay to attract I both its armatures, breaking the holding circuit extending through the selected relays 121, 122, 123, 124 and 125, and the start relay 126. the attraction of the righthand armature opensthe holding circuit of the re lease inagnets178 and 179, and the type selecting magnets 132, 133, 134 and 135. The opening of the holding circuits of the respective relays and magnets ,restores'the selected mechanism of the printer to its n0rinai osition for the reception of further selecting impulses. The closure of the right-hand alternate contact of clear-out to t e paper carriage.
relay 180 establishes an energizing circuit for a retractor relay 153 extending from battery 104, right-hand armature and alternate contact of clear-out relay 180, and the winding of retractor relay 153 to ground. The retractor relay 153. upon energizing closes a circuit extending from battery 113, winding of retractor magnet 155. and the righthand armature o't' retractor relay 153 to ground. The retractor magnet pulls up its arl'nature (not shown) to]: causing the release and the rest oration of the shaft carrying both the type wheel and the stop member 166 to its normal position. The instant the contact member 166 starts to return to its normal position. the contact between the member 166 is broken; Thus, thejcircuit -For the printing magnet 105 is severed for causing the tiecncrgizatitni of this magnet.
The circuit n'eviously traced from battcrytltl l, extending from clear-out relay 130 and the space locking relay 107, also causes the encrgizat ion and locking up of space locking relay 107. The locking circuit for the space locking relay 107 extends from battery 114, winding of spacing magnet 130, conductor 115, right-hand armature and contact of space locking relay 107. righthand winding of this relay, and the righthand normal contact and armature of relay 136 to ground. The space magnet 130 attracts its arn'iature 13$), causing the stepping pawl attached thereto to engage the teeth of a ratchet wheel 137, advancing this wheel through the space of one tooth. The ratchet wheel 137 carries a drum 138, upon which is wound, illustrated in the previously referred topatent, a cord connected As this cord is wound upon the drum 138, due to theengagement of the teeth of ratchet wheel 137 by the stepping pawl controlled by spaclng magnet 130, the paper carriage will be moved from right to left. The operat on of the spacing magnet is insured irrespective of length of the operating impulse, as the armature of the space .loclking relay 107 is held in its actuated position until the armature 139 of the spacing magnet 130 is attracted' a suflicient distance to cause an insulated pin carried at one extremity thereof to engage contact spring 116. The engagement of the insulated pin of contact spring 116 causes the closure of contacts117 and 118. The engagement of contact 117 causes the right-hand winding of space locking rclay 107 to be short circuited through conductor 119. Space locking relay 107 thereupon releases its armature, opening the energizing circuit of spacing magnet 130. However, before the spacing magnet 130 is deenergized, a circuit is established upon the engagement of contact spring 118 extending from battery 120, conductor 27, lefthand normal contact and armature of relay 21, and the winding of rela Y 22 to ground. Relay 22 upon energizing c oses at its contact an operating circuit for relay 21 extending from battery through the winding of relay 15, oil normal contact 33, left-hand contact and armature of relay 16, left-hand armature and contact of ,relay 15, righthand contact and armature of relay 16, winding of relay 21, left-hand contact and armature of relay 22, off normal contact 34 winding of release magnet 17, winding of relay 19-, lett-hand armature of relay 14, and the right-hand armature of relay 11- to ground. Relay 21 upon attracting its armatures, closes at the right-hand contact thereof a locking circuit extending from battery through the winding of relay 15, ofl normal contact of relay 33, left-hand contact and armature of relay 1(, left-hand. armature and contact of relay 15, right-hand contact and arn'iature of relay 16, winding of relay 21, right-hand contact and armature of relay 21, oil normal contact 34, winding of release magnet 17, winding of relay 19, right-hand armature and contact of relay 14-, and the right-hand armature and contact of relay 11 to ground. The attraction of the lclt-hand armature of relay 21 opens the operating circuit of relay 22, which thereupon releases its armature. The circuit just traced includes the winding of release magnet 17 of the selector switch B, which in energizing attracts its armature for causing the restoration of the selector switch mechanism to normal.
Since the subscribers number comprises a series of digits, usually four in number, it is desired to equip the printer mechanism with means whereby the type carriage, after i printing four digits, will be automatically restored to normal. .In the present invention this is accomplished by mounting a set of contact springs 142 and 143 in close proximity to the drum 138. Secured to the drum 138 is an insulated pin 144. Pin 144 is thus advanced for each movementof the drum 138, and since the contactsprings- 142 and 143 are arranged to be engaged by the pin 144 after the drum 148 has been advanced four steps, contact spring 142 will thus disengage its associated contact While contact spring 143 will be. brought into engagement with its contact. The disengagement of contact 142 causes the deenergization and re lease of shit't magnet 170. Upon the engagement of contact 143 with its associated contact, a circuit is established extending from battery 145 through contact spring 143,-conductor 146, winding of line feed relay 110, left hand armature and contact of selecting relay 123, contact and armatureof relay 125, Winding otrelay 192, and the armature and contact of relay 126 to ground. Line feed relay 110 uponenergizing closes through its contact a circuit for the line' feed magnet 112 extending from battery through the right-hand contact and armature of relay 18, conductor 26, winding oi line teed mag net 112, conductor 14%, and the armature and contact of line feed relay 110 to ground. Line feed magnet 112 attracting its armatures closes at its right-hand contact an energizing circuit for carriage return relay 191. This energizing circuit extends from battery through the normal contacts and armatures of the selected relay 121, 122 and 123, conductor 150, winding of relay 136, right-hand'winding of carriage return rclay 191, and the. right-hand contact and armature of line feed magnet 112 to ground. Upon the energizat'ion of relay 136, a locle ing. circuit for the line feed magnet 112 is established extending from battery tln-ough. the right-hand contact of relay 18, conductor 26, winding of line feed magnet 112-, left-hand contact and armature of line teed magnet 112, and the alternate contact and armature of relay 136 to ground. Carriage return relay 190 closes at its arn'iature a circuit for the carriage return magnet 196. The energizing circuit for the carriage return magnet 196 extends from battery through the winding of the carriage return magnet 196, alternate contact of carriage return relay 191,. and the left-hand winding of carriage return relay 191 and contact 151 in parallel to ground. The energization of the carriage return magnet 196 causes the disengagement.
of a holding pawl (not shown) associated with the ratchet wheel 137 to be released. The disengagement of the holding pawl under the control of the carriage return magnet 196 thereupon releases the ratchet wheel 197, which is restored to normal due to the action of a spring (not shown). the limitof the carriage return is reached, the pin 144, engages contact. spring 151, causing the closure of the cont act associated there- .with and the short circuiting of the holding winding of the carriage return relay 191. The carriage return relay 191 is thereupon deenergizcd. Consequently. the carriage return magnet 196 is caused to release the holding pawl controlled thereby tor ctlccting the engagement thereof with the ratchet wheel 137, as the paper carriage is stepped forward for a line of print. The energization of the line feed magnet also causes the operation of a suitable stepping pawl tor shifting the paper or other printing medium to a new line.
For the selection of certain combinations of groups of the selecting relays and mag-- nets of the printer mechanism shown in Fig. 2, it is necessary, for certain positions of the vertical shaft 43, that a larger number of circuits be selected than is possible with the use of the double and single brush arrangement as shown at 35 and 36. Thus, when the brushes 35 and 36 are on the first level or first set of contacts, relay $20 isenergized. for closing through its contacts energizing! circuits for the selecting relays and 125 in addition (Ta those established through the brushes 35 and 36 as well as the selector magnets corresponding thereto.
From the above description it is "evident that the present invention provides a system whereby a printed record may he made of the operation of an automatic telephone substation dial. By means of such an arrange ment. it is possible to determine whether it is psychologically possible for the ordinary telephone user to set up a connection involring more than four digits. it is of course understood that the mechanism may be rearranged for enabling the printing of a larger number of digits without departing from the spirit and scope of the invention.
l l hat is claimed is:
1. In combination, a telephone line ex tendiug between a central otlice and a substation, telephone equipment. located at the substation and connected with the line including a calling dial, a step-by-step selector switch at the central station responsive to impulses transmitted over said line due to the operation of the calling dial, and areceiving' printer comprising a plurality of selector magnets responsive to the positioning of said selector switch in accordance with the operation of said calling dial, a printing magnet, and means tlSSOtfltllttl with said selector switch and operated due to the, positioning thereof for conditioning an energizing circuit for said printing magnet whereby the operation of said calling dial will he recorded.
2. In con'ibination, a telephone line extending between a central oilice and a substation, telephone equipment located at the substation and connected with the line including a calling diah a stop-hr-stc ii selector switch at the central station responsirc toinipulses transmitted over said line due to the operation of the calling dial, a rcccir ingprinter comprising a plurality of selector magnets responsive to the positioning of said selector switch-in accordance with the o 'ieration oi said calling dial, means for causi 'ig the printing of the character selected through the operation of said selector n'iagnets, and means controlled by the print-- or mechanism for causing the restoration of the selector switch at the central station to normal following the printing of the selected character.
.3. in combination. a telephone line eX- tending between a substationand a central otfice, telephone equipment located at the substation including a calling dial, a step by step selector switch at the central oflice having a plurality of contacts and responsive to impulses transmitted over said line due to the operation of the calling dial to select predetermined ones of said contacts, a dialed by the operation of said calling plurality of local circuits connected to the dial. contacts of said selector switch, and a. re- In witness whereof we hereunto subscribe 10 ceiving printer having its selecting mechaour names this 17th day of December, A. D.
' nisms connected in said local circuits and 1920.
operated directly through the contacts of ALBEN E.-LUNDELL. said selector switch for recording the digits ARTHUR B. SPERRY.
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