Historical Document · 1891
US 447,918 Automatic Telephone-Exchange
Strowger's founding patent.
Historical Document · 1891
Strowger's founding patent.
(Np Model.) 3 Sheets--Sheet 1. A. B. STROWGER. AUTOMATIC TELEPHONE EXCHANGE. N0. 447,918.' ‘Patented Mar. 10, 1891. § Wifnesses: . In Yenlar : 1m: max! mu cm. rum-mum. wmlmm; a. c. (No Model.) - - 3 Sheets-Sheet 2. A. B. STROWGER. AUTOMATIC TELEPHONE EXCHANGE. ‘No. 447,918. ‘ I Patented Mar. 10,1891. *“1 ;/// H”? ‘7M (Aw-“$4. ! ' ‘LE1 §1 l l l I Mil/‘125555 .- l i l | I I i _l ln van/0r .' m: noun runs 00., mm" vmuncmn, n. c. F m0 M a L B. ¢S ml. R 0 “W G E 3 Sheets—Sheet 3. R.. AUTOMATIC TELEPHONE EXCHANGE. _ No. 447,918. Patented Mar.- 10, 189.1. - ‘A 3:111:31” . ~ 1 kWh-1555,95 ( we man's verzns cm, warournm, wlsnlm'rou. 04 c. 0 10 u" UNITED STATES PATENT OFFICE. ALMON B. STROIVGER, OF KANSAS CITY, MISSOURI. AUTOMATIC TELEPHONE-EXCHANGE. SPECIFICATION forming part of Letters Patent No. 447,918, dated March 10, 1891. ' Application ?ledgMaroh 12, I889. Serial No. 303,027. '(No model.) With this brief outline, I will proceed to Be it known that I, ALMON B. SrRowGER, a more fully describe my invention and eluci citizen of the United States, residing at Kan» date its workings by the aid of the accompa 55 sas City, in the county of Jackson and State of n y in g drawings. To all whom it may concern. Figure I represents in a perspective view Missouri, have invented certain new and use ful Improvements in Automatic Telephone‘ my invention, showing at a distant sub-sta Exchanges; and I do hereby declare the fol tion one telephone and its exchange device lowing to be a full, clear, and exact descrip at the central o?‘ice, also the mainline wires tion of the invention, such as will enable others connecting the central office with the sub station. Fig. II represents four of snchde IO skilled in the art to which it appertains to vices as is represented by Fig. I, showing the make and use the same.‘ My invention relates to an improvement in manner in which the cylinders are connected, automatic, telephonic, telegraphic, and other also the trend of the electrical current from 65 electrical exchanges. 15 . one sub-station to another through the cen< The object is to provide means whereby a tral of?ce. Fig. 111 is a plan View of a series person at one station may make connection of cylinders, line - wires, and connectives, with any other station in the system, by the showing the normal position of the circuit aid of electrical appliances, without the as closers. Fig. IV is a sectional view showing sistance of an operator at the central station. the magnets, levers, and pawls by which the A further object is to provide means of the device is operated. , Fig. Vis a detail view of above character which shall be reliable and the ratchet-wheels and pawls for operating the same. Fig. VI is a sectional view of the adapted to general use. cylinders, showing more clearly the construc. 75 With these ends in view my invention con sists in certain features of construction and tion of the circuit- closer ‘and feather~and . 25 combination of parts, as will be hereinafter groove attachment. Referring to the drawings by letter, A rep described and pointed out in the claims. The same general plan is adopted as in the resents a hollow cylinder constructed of glass, systems now in use, in that of having a prin wood, or any other suitable substance which cipal or central station, (central o?‘ice,) and a is a non-conductor of electricity, supported in number of sub-stations, the said sub-stations any well-known or approved manner. The being placed in electrical connection with cylinders are provided with perforations a, each other at the central o?ice by and through arranged in transverse and vertical rows. 1; represents the wire connections extend 85 line~wires, which line-wires, for the sake of brevity, will be designated “phonic” wires, ing from the inside of the cylinder through 35 (introducing the ancient obsolete fornn) but the perforations a to the main-line wires N differ in that of having, in addition to the and is attached thereto. Their use is to con said phonic wires, a series of wires (one or duct the electricity, when in contact with the more) to operate the hereinafter~described circuit-closing needle 0 C’, to and via the mechanisms located at the central office. At line-wires N to the desired sub-station. The the sub-stations are the appliances which are terminals of said connectives within the cyl used to transmit and receive communication, inder are shown at b, Fig. VI. In this last as telephones and keys. At the central office namcd ?gure the circuit~closing arm is rep are arranged in methodical order as many resented in parts, in which C is the circuit 95 switch-cylinders, with their attendant mech closing sleeve and is ?rmly attached to the end of the sleeve-rod D. \Vithin this 45 anisms, as there are sub-stations. The above lower mentioned phonic wires trend within the cen circuit-closing sleeve isclosely ?tted the cir. tral oi?ce in close proximity to each cylinder. cult-closing needle 0’, held in such a man From each phonic wire and attached thereto ner as to be in perfect- electrical contact with wire terminals, connectives, or “legs ” extend the wire-terminal b by the spring 0. The rod (see Fig. V1,) is located along the axle-' 50 to the inside of each cylinder, there being as D, many connectives attached to each phonic line of the cylinder and is free to rotateand wire as there are sub-stations. . movelongitudinally. The lower end of the 2 447,918 rod D is sleeved, into which is inserted the end of the cylinders upwardly, and by places upper portion of ' the ratol1et~rod D’. This in each row——as, for example, 1 2 3 at &c.— sleeve construction between the rods D and to the right or left of a given vertical row, so D’ allows the ratchet-rod D’ to have a longi that, supposing there were one hundred per tudinal motion only, thereby keeping the forations in each of the rows, No. 310 would ratchet-teeth (Z continuously toward its at be in the third row from the bottom, ten tendant pawl. spaces to the right or left of the vertical in The ratchet-rod I)’ is provided outside of itial line. 75 the cylinderA and conveniently below it with Each connective wire B and phonic line a series of ratchet-teeth (l, by means of which wire N, Figs. II and III, with which the con the rods D and D’ are moved longitudinally. nections are attached, is also numbered to cor— The wheels E and E’, through the hub of respond with the number of the perforations which the rod D extends with a feather-and a, through which the terminals extend. groove connection R, (see Fiv. \’l,l so as to The person wishing to place his transmitter cause the rotation of the rod D and at the and earphone in connection with those of an same time admit of its longitudinal sliding other, he will do so by successively pressing movement therein, are provided on their pe or depressing the keys, which cause the cir ripheries with a series of ratchet-teeth e and cuit-closer O C’ to move. For example, if 85 20 e’, by which the rod D is rotated, and with it the circuit-closer C and C’. G 11 I represent levers having pawls g h i pivoted in their ends in position to engage the ratchet-teeth, with which they are respect ively in contact. Each lever has a vibra 25 tory movement and is oscillated by the alter nate energizing and tie-energizing of their re telephone 288 wishes to place himself in con~ nection with telephone 315 he will do so by pressing the key marked G" three times, then the key marked 11’ once, and then the key marked I’ ?ve times. IIis circuit-closer C C’ is then in contact with wire-terminal No. 315. In Fig. II sub-station No. 288 is represented as being in connection with sub spective magnets, thereby imparting motion station No. 315. This is known by the posi to its adjacent ratchet-teeth and consequently tions of the circuit-closer C of cylinder-No. 95 At each pulsa~ 288, the course of the electrical current being ’ the circuit-closing needle 0’. tion of the push~button at the sub-station indicated by arrows. Had its oircuitecloser made at the will of the operator causes, 0 been turned to the next wire indicated in through the channels thus described, the cir the drawings, 288 would be in connection with cuit~closing needle C’ to move from row to row and from wire to wire in the row. lVhen 11. The person at telephone 315 will take I00 down his earphone. The two are then able to converse with each other. When conver only three levers are used, the dog T (see Figs. land II) would be necessary. Its use is ob sation is ended, the person calling up hangs VlOllS. up his earphone, depresses key marked P’, The magnets K K K arelocated in suitable which causes the magnets K’ to be energized, 105 positions that when energized by the manipu attracting the armatures, thereby Withdraw lation of certain keys at the sub-station, oper ing the several pawls from their engagement ate their'respective levers. A set of magnets with the ratchet-teeth and allow the circuit K’ K’ K’ K’ are also located in suitable posi closer C C’ to fall and return to its initial tions, that when energized their respective point. levers P serve to release the pawls from their If a person has called up the wrong number, 45 engagement with the ratchet-teeth and allow he will push the_ key marked P’ and start the circuit‘closing needle 0 O’ to assume the over again. initial position by the aid of gravity and the The size of the cylinder A will depend spring S. At each sub-station there is a set solely upon the number of wires required in :15 of keys marked, respectively, G’, H’, I’, and the system and the distance apart which it P’. Each key is connected by wire with its may be found most expedient to place them; respective lettered magnet at the centralof?ce, and it is also evident that various slight and when pressed an electrical circuit is es changes might be resorted to in the mechan tablished, it being understood that both ends ical construction of the several parts which I I20 of the wire are grounded or connected with have described without materially departing 55 a return-tap, it- also being understood that a from the spirit and scope of my invention, battery is used to generate the electricity and hence I do not wish to belimited strictly and may be located at the sub-station be tween the keys and the ground. The line wire N extends from the telephone to and thereto. - > Having thus fully described my invention, I25 what I claim as new, and desire to secure by within the central o?‘ice, there connected by Letters Patent, is—— the circuit-closing connective wire \V to the 1. In a system of telephone, telegraph, or circuit-closing needle 0, and also by connect other electrical exchange, the combination, ive B to the inside of each cylinder. with a series of wires leading to different sta Each perforation a of the cylinder A is tions in the system and having their ends in 65 numbered with respect to an initial or start sulated and held in curved rows, of a contact ing point on the cylinder-for example, in needle supported at the axis of the rows, rows numbered 1 2 3 4, &c.—from the lower mechanism for moving the needle from row 447,918 to row, mechanism for moving the needle t. In a system of electrical exchange, the along the row, magnets for actuatingl said combination, with an insulat-ing-cylinder, a mechanisms, and wires leading from a sub system of wires having their ends extending station for conducting electricity to energize to the inside of the cylinder, and a rotary and the said magnets, substantially as set forth. longitudinally-movable rod located at the axis 2. In a system of electrical exchange, the of the cylinder, of a sleeved arm fastened to combination, with an insulating-cylinder, a the rod, a contact-needle, levers for mov 35 system of wires having their ends extending ing the rod longitudinally, levers for rotating to the inside of the cylinder, and a rotary and the‘ rod, magnets for actuating the levers, IO longitudinally~movable rod located at the axis means for pressing the needle outwardly, and of the cylinder, of a contact-needle attached means for energizing the magnet at pleasure, to the rod, levers for moving the rod longi tudinally, levers for rotating the rod, mag substantially as set forth. , 5. In combination, the set of wires having nets for actuating the levers, and means for their ends secured in a cylinder, the cylinder, _, energizing the magnets at pleasure, substan the rod at the axis of the cylinder, the pieces fastened to the red, the levers provided with tially as set forth. 3. In a system of electrical exchange, the pawls pivoted thereto for actuating the rod, 45 combination, with an insulating curved sur the magnets for actuating the levers, the face, a system of wires having their ends ex magnets for actuating the pawls, the keys at the sub-station, and the wires connecting the 20 tending to and through said surface to the keys with the actuating-magnets, substan _ longitudinally-movable rod located at the axis tially as set forth. In testimony whereof I aiiix my signature in of curvature, of a contact-needle fastened to the rod, levers for moving the rod longitudi; presence of two witnesses. concave surface thereof, and a rotary and nally, levers for rotating the rod, magnets for. vibrating the lever, and means for energizing ‘the magnets at pleasure, substantially as set forth. . ' ALMON B. S'I‘ROWGER. Witnesses: BESSIE E. YOUNG, P. O. PHILLIPS.