US990219A - Supervisory signaling system. - Google Patents

Description

w. e. BLAUVELT. SUPEBYISORY SIGNALING SYSTEM. APPLIOATION FILED OUT. 28, 1910.

Patented Apr. 25, 1911.

UNITED STATES PATENT orrron.

WILLIAM G. BLAUVELT, 'OF NEW YORK, N. Y., ASSIGNOR TO AMERICAN TELEPHONE AND TELEGRAPH COMPANY, A CORPORATION OF 'NEW YORK.

SUPERVISORY- SIGNALING SYSTEM.

Specification of Letters Patent.

990,21 Application filed October 26, 1910. Serial No. 589,207.

To all whom it may concern: I

Be it known that I, VVnmmrrG. BLAU- yin/r, residing at New York, borough of Manhattan, in the county of New York and State of New York. have invented certain Improvements in Su'lmrvisory Signaling Systems, of which the following is a spccifi? cation.

This invention directed to the signals em .)l(')ycd for supervising telephone calls. Ordinarily in manual systems, the cord circuit by which the lines are united at the central station has in both the answering and calling ends a single signal device, as an incandescent lamp, which is caused to glow when the receiver of the corresponding substation is upon its hook, and to be extinguished when said receiver is removed. This gives the operator an indication of the conditions at the substations, which is in many instances su'llicient, but in others puts'upon her an undue burden in noting and rcl'nemboring the times of appearance and disappearance of the signals. For example, the zalling subscriber after the completion of a particular conversation, or because there was an *ror in the connection, will keep the receiver off the switchhook when he desires to speak with the operator. Unless the latter observed. the lighting and extinguishing of the called supervisory lamp, this leads herto again ring over the called line, or to wait for the called subscriber to answer. Drag upon the operators work, and delay and annoyance of the subscriber results. A further difficulty arises from the fact that in measured service the operator has no direct means of knowing when the calls have reached a stage at which they should be charged, unless, as before pointed out, she hasseen the changes in the called line supervisory.

The present invention provides plural signals for theca'lled line, by which, for each connection, separate indications are given when the subscriber responds to the ring of the bell and when he terminates the conversation.

In the accompanying diagrammatic drawing my invention is illustrated in connection with a manual cord circuit, though it is to be understood that it is applicable to all systems where similar su )crvision is useful.

The letters A and B esignate telephone substations, the lines a and b of which unite them to jacks J and J respectively, at a central station C. At the central station are circuits for connecting the lines, in the present instance an operators cord circuit 0 being shown, this having an answering plug I and a. calling 'plug P These -appear adjacent to the jacks J and J and therefore A may be consideredas the calling and B as the called substation. In every rcspect,savc as it relates to supervision of the called line, the cord circuit 0 may be as usual, and only the novel portions will be particularly described.

Associated with, the cord circuit is an automatie switching mechanism D,the arrange. ment and functions of which will depend upon the character of the system of which it is a part, but which, in any event, is adapted to assume successive controlling positions in regular sequence. In the present instance, it is employed solely as ameans for governing the supervisory signals of the called subscriber, and for this purpose'it consists of a shaft cZ upon which is fixed a series of\ cams c, the peripheries of which cooperate with springs f to force them against or permit them to separate from contacts 9. These cams, springs and contacts all appear in two places (in the drawing, in dotted lines in their actual relation to the shaft d and in full lines at points most clearly developing the circuit organization. In the latter case, they are distinguished from one another by numerals affixed to their reference letters. The switch shaft with its cams may be moved from position to position by a motor magnet m actuating ratchet mechanism. A pulsator 22 supplies intermittent. currentfrom battery B through conductor 10 to the motor magnet m, and thus rotates the shaft whenever its circuit is completed at one of the contacts of the sequence switch I) to ground or other return conductor. This ground connection may be at some external point or local to the switching mechanism itself, the cam c controlling the latter condition and determining the correct stopping points of the switch shaft. lVhen the spring f cooperating with this cam is separated from the contact g, this being in the positions indicated by the numerals placed at the opposite side of the spring from the contact, the projection 11 upon said spring lies in a depressiorrlQ in the periphery of the cam, and the shaft with e are included in the conductor '10 of the now resting upon contact" there is a, local the associated cams is properly positioned. Upon the completion of the circuit of the motor magnet in at some point in the system the projection rides out of the depression, and when resting upon elevations of the cam e closes local circuit for the motor magnet which insures rotation of the shaft to the next position at which the cams are to stop, regardless of external conditions. The numerals applied to the contacts of the remaining cams show the positions in which said contacts are closed. ()f the other cams, c has its spring f normally resting upon a contact r which is joined to the front contact 13 of a relay R in the third conductor L of the cord between the central station battery and the sleeve contact of the calling plug P I The normal contact 13 of relay R is joined to the contact 9 of cam 6 The spring f of this cam and contact 9' of cam motor magnet. From spring f of earn a a conductor 14 leads to the front contact 15 of the called line supervisory relay lt situ-' ated in the cord conductor L and energized only when the receiver at the substation is off its switchhook. The alternate contact g is united by a conductor 10 through a resistance 17 with parallel branches 18 and 19, in which are a ringing signal 0 and a disconnecting signal 0 respectively, both of these preferably being incandescent lamps. Resistances 20 and 21am interposed bet ween the conductor 16 and the lamp 0, and the juncture of these resistances is connected to battery. The conductors 18 and 19 tenni nate, respectively, iircontaets g and g of cam 6 the spring f of which is joined to ground. As thus described illustrated both signal lamps O and. 0 may be said to be directly associated with one and the same :ord circuit, C, and particularly with the calling end of said cord circuit, and both positioned and adapted to signal one and the same central station operator.

The operator, having received a call for substation I3 and found its line Z) not in use, inserts the plug l of'thc cord circuit. with which she has answered into the jack J? This causes the energization of relay lt in circuit with the cutoll' relay of the called line. The closure of contact 13, together with normal contact of the sequence switch, gives a ground for comluctor 10, and impulses ot currentarc applied by the pulsa tor [i to the motor magnet of the switclnwhich is driven to its second position. Ground'c't oring 7"- circuit for the lamp tl'irough'conductor l8 and re, d l, lighting thislamp and thus preparing it to indicate the suhscriheus response the ringing of his bell. The signalhii therefore been remlered cllectivc by the a sd'ciation of the' jack and plum' The subsequent taking down of the receiver energizes supervisory relay R and. gives a. circuit through its front contact 15, conduct r 14, spring 7, contact g" and conductor 10 for the motor magnet. The switch D thereupon takes its third position, opening contactgq and thus extinguishing the lamp 0 to inform the operator that the called subscriber has answered. Upon its alternate contact 9*" the spring f closes the local circuit 15.) for the disconnecting lamp 0 but this is shunted by a circuit from battery to ground through resistance 17, conductor 16, switch contact 5 conductor 14: and contact 15of relay R It does not receive sutlicient current to cause it to glow, but has been prepared t'or signaling by the removal of the receiver. \V hen, however, the. called subscriber hangs up the receiver, the armature of relay R falls otl', breaking the shunt circuit and lamp 0 lights. This gives to the operator positive knowledge that there has been connnunication between the calling and called substations, and that, if the supervisory lamp of the calling line also lights, she may withdraw the plug P and, in measured service, record the call. If the calling line supervisory remains out, it at once indicates to the operator, withouteffort to recall previous conditions, that she should again connect her set with the cord to inquire what is desired. When the operator pulled out the calling plug, the relay R, be ing'rcleased, completed at its back contact 13 a circuit for the motor magnet by way of switch contact g and conductor 10. The switch I) advanced to its normal position and was stopped by the opening of the contact H the called subscriber had failed to answer, the san'lc circuit would have resulted upon the deiincrgization of relay R in the second position, and contact 9 would still be closed in the third position, causing the completerestoration of the switch.

Having thus described my invention, I claim: 7

I. la a telephone system, a central station and a substation, a plurality. of supervisory signal devices at the central station, all posilioncd and adapted to signal one and the same. central station operator and means for successively bringing said signal devices un der the control of the substation.

2. in a tclc 'ihone system, a central station and a substation, a plurality of signal devices at the central station, all positioned and adaptedto signal one and the same central station operator aud automatic mechanism at the central station for successively bringing said signal devices under the control of the sul'istation.

5). in a telephone system, a central station and :1 substation, two' supcrvisoty signals, both positioned and adapted to signal, one and the same central station operator and means controllable-by'central station apparatus for rendering one signal effective and by substation apparatus for rendering the other signal effective. i

4. Ina telephone system, a central station and a called substation, and two supervisory rality of signal devices associated with the ing circuit andboth controllable from one'of 30. two telephone-lines when such linesare cinsignals both positioned and adapted to sig-v iial one and the same central station operator and controllable by thesubstation apparatus at different stages of a call.

5. The combination with telephone lines, of a connecting circuit therefor, and a plu connecting circuit, all of said signal devices being positioned and adapted to signal one and the same operator and controllable during a single connection by the condition of one of the substation lines.'

' 6. The combination with telephone lines of a connecting circuit therefor, anda lurality of supervisory signal devices directly associated with the calling end of the con- 'necting circuit and controlled by a called telephone line.

7. The combination with telepho e lines, of a connecting circuit therefor, a-no a. ring ing supervisory signal and a disconnecting signal directly associated with the connectnected by the connecting circuit;

" 8. -'lhe'combination witha telephone substation apparatus, of a cuit includin plurality of signal .d'evices, switching means for actively associating. one and then an other of the signal devices-with the circuit,

, substation apparatus and means controlled by the condition of the for actuating the switching means. i i

9. The 'combination'with. telephone lines and a connecting circuit, of -'a sequence switch providedwith a. plurality of contacts, called line supervisory. signals connected with said contacts and effective in different positions of the sequence switch, and means for actuating the sequence Switch to said different positions.

10. Telephone lines, a connecting circuit therefor, a relay associated with the connect jing circuit, switching mechanism provided with motor Ineans and With a plurality of contacts, said motor means being controlled by the relay, and called line supervisory sig- "nals joined to different contacts of the switching mechanism. 11..Telephone l1nes, a connecting circuit therefor, switching mechanism associated with the connecting circuit and having a plurality ofcontacts a ringing signal connected to one contact of the switching mechanism, a disconnecting signal connected to another contact thereof, means controlled by uniting the connecting circuit with a called line for closing the contact to .theringing signal, and means operating upon .the response of the called s'ubscriberfor closing the contact to the disconnecting signal.

12. Telephone lines, a. connecting circuit therefor, switching mechanism associated with the connecting circuit and having motor means and a plurality of contacts, a ringing signal connected to one contact of the switching mechanism, a disconnecting signal connected to another contact thereof, a relay {controlled by uniting the connecting circuit with the called line for actuatingthe motor. means to close the contact to the rim ing signal, and a supervisory relay therea er controlling the motor means to close the to the disconnecting si al. A

In .testimonyfwhereo I have signed my name to this specification in the presenceiof two subscribing witnesses, this l8th dayiol Qctober 1910. .WILLI'AM .G. BLAUVEIJT. fW'itnessesg;

Pnnnr VVooLiicorr, WILBUR L. VAT'IIER.

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