US502466A - James l - Google Patents

Description

(No Mdel.) l

. J. L. MGQUARRIE.

TELEPHONE CIRCUIT AND APPARATUS. No. 502,466.'

Patented Aug. 1.1893.

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UNTTED STATESN NPATENT OFFICE.

JAMES L. MCQUARRIE, OF BOSTON, MASSACHUSETTS, ASSIGNOR TO THE AMERICAN BELL TELEPHONE COMPANY, OF SAME PLACE.

TELEPHONE CIRCUIT AND APPARATUS.

SPECIFICATION forming part of Letters Patent No. 502,466, dated August 1, 1893.

Application filed May 25, 1893. Serial No. 475,449. (No model.)

To all whom it may concern: one of said switchboards the said. line ter- Be it known that I, JAMES L. MCQUARRIE, `minates in a clearing out annunciator and residing at Boston, in the county of Suffolk plug, while at the other switchboard the line and State of Massachusetts, have invented extends through the several sections thereof, 5 certain Improvements in Telephone Circuits having looped in at each section a clearing and Apparatus, of which the following is a out spring jack, which constitutes anew feaspecilication. ture in such circuits. The clearing out This invention relates totelephone central jack performs the usual functions of a conoiiice or exchange switchboard `circuits and necting jack upon multiple switchboards, and 6o ro apparatus, and especially to the trunk lines serves the additional purposes of, first: an which are employed as links between two disautomatic disconnector of the trunk line with 5 tant points, or terminals, which may be loa substation line, and, second, when the trunk cated on separate switchboards in the same line is connected with a substation line at room or building, or may be in the telephone one terminal, of visually indicating at all the r 5 exchanges of two widely separated towns or other sections of the switchboard the fact that l cit-ies. the line is in use, and also of interposing an PV Owing to the increased use of the telephone obstacle whereby the operators are prevented and the consequent multiplication of subfrom inserting a connecting plug therein. stations connected with exchanges, it has In carrying out my invention I associate 7o 2o been found desirable and necessary to inan additional conductor with the trunk line,

crease the number of such central stations, which extends with it and at the plug termiand as the subscribers of the several central nal thereof has connected therein normally stations wish to converse with one another, through the back contact of an interposed key trunk conductors are extended between the the minor portion of a main battery which is z 5 several exchanges, which thus serve as links grounded at one pole; at the opposite termibetween the respective switchboards over nal the said conductor is branched to a norwhich signaling and conversation may be carmally open spring in each clearing ont jack. ried on between the substations associated Ialso provide between each of said terminals therewith. At one or both of the terminals an operators instruction circuit of any suit- 8o 3o of such trunk lines there are usually some able character. Each clearing out jack conmeans provided to .indicate to the operator sists preferably of a body of insulating matethere that the substations which have been rial supporting an electro magnet andsuitable connected for conversational purposes, have connecting springs and is provided with a finished, such means being denominated plug orifice in which there is located a self 35 clearing out annunciators, or visual sigretracting longitudinallymovable circuit connais, or sometimes such an indication is controller, by means of which, when the looping l veyed by speech from one operator to the or connecting plug is inserted in said orifice, f other. In all such means or devices more or the circuit connections are made and the cirless time is taken up in the notification and cuit controller is operated and locked, and 9o F `4o frequently an operator is too busy to make the minor portion of said battery or source of the disconnection required, and consequently electricity at the other terminal is closed to a trunk line forming part of a line of comearth through the electro magnets of all the munication on which a conversation latelyin clearing out jacks at the several switchboard progress has been completed is thought to be sections, and line in use indicators are op- 45 still inactive employment, and consequently erated. Upon the termination of conversa remains idle and useless, when its employtion between two substations connected by ment may be required by other operators at means of such a linking trunk line, the clearother sections of the switchboard. ing out annunciator at the plug terminal end My invention relates to a trunk line which thereof is operated when either of said sub- :oo 5o extends between distant terminals, each terstations ring ott, whereupon the operator there minal being located upon a switchboard. At A noticing its fall withdraws the connecting plug and presses the key in the kbattery line, thereby closing the whole battery current through the electromagnet of the clearing out jack at the other terminal in which the connecting plug of the other substation is inserted, energizing the same, and operates the locking device of the self retracting circuit controller, unlocking the same, whereupon the connecting plug of the said substation line is forcibly ejected from the jack, thereby automatically disconnecting the line, and the plug fallsnto its normal position upon the operators table; at the same time the line in use indicators of the several clearing out jacks upon the several sections of the switchboard are caused to indicate that the line is not in use; all of which I will now proceed to describe. in detail, and to point out in the appended claims.-

In the drawings forming a part of this specification Figures 1 and 2 are sectional Views of my improved clearing out jack, the first in its unused position and the second with a plug inserted, and Figure 8 is a diagrammatic representation of circuits, illustrating the connection of two substations by Vmeans of a trunk lineY extending between Vtwo central stations, toV which the substations are respectively connected. y

In Figs. 1 and 2, 3 represents the front or face of a switchboard to the rear of which the clearing out jacks are attached, or it may represent a rubber strip to which a number of other connecting jacks are attached.

4 is a metal thimble to which thejack is directly attached.

The body 5-of the jack, is of hard rubber, and bears'upon 'its outer end an electro magnet 6, which has an armature 9 pivoted at 8. Upon its end, the armature is provided with a lever 7, which extends over its top, the end of which is under the outer end of the lever 10, pivoted at 11.

15 is a chamber hollowed out in the end of the body 5, into which projects an arm 12 from the lever 10, the end of which is inclined as shown.

15 is a prolongation .of the lever 10, in the Y form of a dat steel spring. It projects through an opening 17 in the rubber strip 3, and is bent downward to form a shield 16.

19 is a spindle located in the center of the body 5,y one end of which bears a cone shaped head 14, which projects into the chamberl. Its other end rests in the thimble 4.

41 is a ring abutment on the spindle and s a spiral spring pressing against it and the rear end of the slot 40 cut through the body 5.

18 and 22 are at springs secured to opposite sides of the body 5, their free ends extending into the slot 40 and pressing upon the insulating section 2O of the spindle 19.

23 is a at spring secured over but insulated from the spring 22; its free end resting upon the spindle 19.

In Fig. 2 a connecting plug P2 is inserted in the thimble 4 and jack J. The spindle 19 is trunk line circuit D which extends between" two distant exchanges X and Y and provided at theforme'r exchange with a clearing out annunciator o2 and a terminal connecting plug P, and at the other exchange with au- `tomatic disconnecting or clearing out jacks J one on each section of the said switchboard. One side 1 of the circuit D is branched by wires 27 to the spring 23 of each jack Jat the terminal Y and the other side 2 thereof is branched by wires 29 to the thimbles 4 of each jack. A local circuit is formed by wire 43 branching to the springs 1S of each jack from which branch there extends legs 44 through the electromagnets 6 to earth e.

c is a conductor extending parallel with the trunk circuit D provided terminal X with a source of electricity B the circuit being from line to key 7c, back to contact b wire ci, to ground e, through a minor portion of the battery B; and at the terminal Y it is branched to the spring 22 of each jack Jby the Wire 26.

O represents a line extending from sub-l station :c to the switchboard at exchange X, andY C represents a similar line extending from substation y to the switchboard at exchange Y. Each of theselines is provided with jacks j for each operators section of the switchboard, and with line aununciators rin a manner well understood.

Ais an instruction circuit provided with operators telephones t at each exchange, and with such other appliances as is usual.

d represents the operators interconnecting apparatus, of which only the connecting plugs and looping cords are shown. Y Y j Y To illustrate theoperation of my invention, let us suppose thata call is sent in from substation ,which operates its annunciator o.

The number of the substation Wanted having been ascertained in the usual manner by the operator, the plug P of the trunk line D is inserted in the jackj of the line C, and the operator at exchange Y is informed through the instruction circuit A of the substation wanted, who then inserts one of the plugs P2 of the loop CZ into the special trunk line jack J upon her switchboard section, and inserts the other plug l?3 into the jacky' of the substation line wanted, and calls up the subscriber there,

vswitching out all of the keyboard apparatus and leaving in simply the plugs and cords when the connection has been made. When Ithe operator at exchange Y inserted the plug P2into the jack J, it forced the spindle circuit l'OO controller 19 inwardly, its cone shaped head 14 striking the lever arm 12 pushing it upward against the resiliency of the spring l5, (whose shield 16 finds an abutment against the plug) which springs back and locks the spindle, as shown in Fig. 2. A circuit is now closed from ground e atexchange X, through a portion of battery B over conductor c, branch 26, throughspindle 19, spring 18, wire 25, to point 24, where a portiongoes through the electro magnet 6 of the jack to ground at e. The remainder of the current passes by the local wire 43 and its branches 25, through the electro magnets of the other jacks J, to ground, and is of sufficient strength to operate their several armatures 9, `and thereby elevate the levers l0, and depress the shields 16 to cover the orifices or `plug holes of the jacks, thus indicating that the line is in use, and also interposing an obstacle to prevent the jack being used. The current is not however strong enough to attract the armature of the connected jack J against the resiliency of the spring 15, and consequently the spindle 19 remains locked. When conversation between the substations has terminated, a ringing off signal is sent in from either or both substations, which operates the clearing out annunciator u2 at exchange X, giving notice to the operator there of the fact, who thereupon withdraws the plug P, and instead of calling the operator at exchange X to disconnect there, she presses the key k to make contact with its anvil, thus opening the shunt wire aand including the Whole or major part of current of the battery in the line c, which is of sufficient strength to operate the armature 9 of the connected jack J, and elevate the lever 10 against the force of the spring 15, and thereby pull the arm 12 from the head of the spindle 19 and unlock it; the spring s on the spindle is thus brought into action, and forcibly propels the spindle and the plug P2 outward until the head .14 is stopped by its abutment, `but the plug is, ejected from the jack entirely and the 1in@ U is disconnected, the plug falling to its place upon the table; at the same time the springs 18 and 22 resume their places upon the insulation 20, and all current is cut olf from battery B. consequently the shields of the sevn eral jacks J move to uncover the jack holes,

and thus indicate that the line is not in use.

Having now fully described my invention, I claim- 1. In a trunk line extending between two telephone switchboards, the combination of a circuit provided at one terminal with a elearing out annunciator and a connecting plug, and at its other terminal with one or more spring jacks, each having a movable circuit controller in its plug orifice, and an electro magnetic locking and tripping device; with an associated normally open circuit provided `with a source of electricity; and akey or circuit switch at one terminal; whereby the said source of electricity is included in said circuit when either of said spring jacks are looped to a substation line, for the purpose set forth.

2. In a trunk line extending between two telephone switch boards, the combination of a metallic circuit provided at one terminal with a clearing out annunciator and a connecting plug and at its other terminal with a spring jack Vhaving a movable circuit controller in its plug orifice and an electro magnetic locking and tripping device; with an associated circuit grounded through a circuit switch and a source of electricity at one end and connected by a normally open branch to the said spring jack; whereby when a substation line is looped to said springjack its connecting plug may be automatically disconnected as set forth.

3. In a trunk line extending between two telephone switch boards, the combination of a metallic circuit provided at one terminal with a clearing out annunciator and a connecting plug, and at its other terminal with one or more spring jacks each having a movable circuit controller in its plug orifice and an electro magnetic line-in-use indicating device; with an associated circuit grounded through a source of electricity at one end and connected by normally open branches to the said spring jacks; whereby when a substation line is looped to one of said spring jacks, the said circuit controller closes the said source of electricity to ground and operates the said line-inuse indicating devices, as set forth.

4. The combination with a trunk line extending between two telephone switchboards, consisting of a metallic conversation and signaling circuit, provided at one terminal with a clearing out annunciator and a connecting plug, and at its other terminal with one or more spriugjaclrs, each having a longitudi- 4nally movable circuit controller in its plug orifice, and provided with electro magnetic locking, tripping, and line-in-use indicating devices; with an associated circuit grounded through a circuit switch and a minor portion of a source of electricity at one end, and connected by normally open branches to the said springjacks: whereby when a substation line is looped atone of the said springjacks,the said circuit controller closes the said minor source of electricity to ground and operates the said line-in-use indicating device; and whereby when the said circuit switch is operated to include the major portion of the said source of electricity, the said substation line is disconnected and the said line-in-use indicators are restored to their normal condition, as set forth.

5. In a trunk line, extending between two telephone switch boards, the combination of a metallic circuit provided at one terminal with a clearing out annunciator anda connecting plug, and at its other terminal with one or more springjacks, each having a mov- IOO IIO

cuit switch with the said brauch inclndinD the source of electricity.

In testimony whereof I havesigned my name to this specification, in the presence of two subscribing Witnesses, this 16th day of 15 May, 1893.

JAMES L. MCQUARRIE. Witnesses:

GEO. WILLIS PIERCE, JOSEPH A. GATELY.

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