US1640325A - Messenger-call circuits and switching apparatus therefor - Google Patents

Description

E 1,640,525 ug. 23, 1927- G w, JANSON MESSENGER CALL CIRCUITS AND SWITCHING APPARATUS THEREFOR Filed Sept. 26, 1925 2 Sheet s-Sheet l 2E Pas/61012 vZ/A f 6/?00 1/050 Gea/ye i1. Jamm/z I 1,640,325 Aug. 23, 1927.. G. W. JANSON MESSENGER CALL CIRCUITS ANI; SWITCHING APPARATUS THEREFOR Filed Sept. 26, 1925 2 Sheets-Sheet 2 Patented Aug. 23, 1927. v Q

UNITED STATES PATENT o-FFlcE.

oEoaoE w. ew. or Nu'rLEir, NEw JERSEY, assumes; no rn wEs'rEnN UNION TELEGRAPH COMPANY, or NEw YOEK,'N. Y., A coaroaa'rroN on NEW YORK.

MESSENGER-CALL ornomrs AND SWITCHING arrnna'rus 'rnmmi'on Application filed September, 1925., .Serial No. 58,911;

This invention relates to messenger call circuits wherein a number of call boxes m various subscribers offices are connected in series in a loop circuit from a central oflice in which is located a receivin ap aratus including a register for recording t e signals on a movin tape. a

The purpose 0 my invention is to provide a circuit equipment which will cause an indication at the central oflice upon the occurrence of any fault, such as an open cir-. cuit or a ground, and with means'for immediately placing the circuit in condition to maintain the system in operation until the fault can be repaired so that there shall be no interruption in the messenger service. A further object of my invention is to provide a single switch devicewhich will automatically place the circuit in condition to continue in operation upon being moved into one position or another position by the attendant and which will indicate when the correct position has been found, so that the attendant will know when the circuit is in operative condition and also the character of the fault.

In the following description I shall refer to the accompanying drawings, in which Figure 1 is a theoretical diagram of the circuits of a messenger call-system 0n carrying out my invention; Fig. 2 is a theoretical diagram of the same circuits embodying my unitary fault correcting switch and showing the position of the switch blades under normal conditions when no fault exists; Fig.

3 is a diagrammatic illustration of the several positions of my switch; and F ig, 4 is a cross section of the switch on the line 4.--4

of Fig. 2.

The loop circuit or line L, L,, containing the subscribers call boxes B, B B etc., is connected at the central station CS atone end through the jack J, relay R and resistance T to a source of current supply E. The other end of the loop circuit isconnected at the central station through jack J relay R conductor 10, and contacts 1 and 4 of switch -S to ground. The contacts of relays R and R are connected respectively to switches S and S in such manner that, by changing the position of the switch levers, either the frontor the back contacts of the relays may be used to operate the local register 1) and the buzzer Z. The triple pole switch S is arranged to remove the ground G and subto that stitute battery E when necessary to overcome a fault in the line. This switch also changes the connections of the register and buzzer circuits. vThe pilot relay PR is placed in the ground connection ofthe, signal lamp SL so and thereby controlsthe buzzer Z.

- When the line is in normal condition,"current flows from the source E-through'the 1 resistance T, relay R, ,jack J and the. line containing the call boxes B, B ,,e'tc., 66 returning through jack J relay ,con- I tact points 1 and 4 of switch S ur, at G. The armatures of relays Ed R, are'thus held against their from thereby keeping thelocal buzzer andregister 7 circuits open. When any call box such as B is operated, the break or signal wheel W opens the line the number of'times required to produce the signal of thatparticular box. Each break causes the-armatures of both relays R and R, to fall against "their back contacts, thus closing the circuits of the local signal lam SL, pilot relay PR, buzzer Z and register Current now flows from source Eithrough the armature. and back contact of relay R,conta'cts 6 and 3 of switch S, resistance T and register Dv to ground at G,, thus causing the register to record the signal or box number on the ta ve.

Simultaneously current flows from t c source E through the-armature and back contact of relay R si nallamp SL, contacts 5 and 2 of switch ,and the pilot relay PR to ground at G,. This causes the si nal lamp SL to glow and the pilot ready P to close the local circuit containing the buzzer Z.

Each signal box is rovided with two break wheels W and the former opening'and closing the circuit .as the spring tongue t moves across the ap between adjacent teeth on the wheel and the other toothed wheel W, applying a ground con nection through. the tongue t after the opening of the circuitv by the first wheel.

The teeth of the two wheels are staggered so that the ground: applied by the wheel W and ton ue t, is maintained fora time equal uring which the wheel W had 0 ened the circult. It will be seen, there ore,

that the relay R, will be deprived of current by the grounding at the tongue t, and thus a lowits armature to remain on the back contact durin the transmission of each di "t of any signa due to the fact as above exno I plained, thata call box opens and thereafter I both closes and rounds the line simultaneously, thereby s unting out the rtion of the line containing therelay R hen the signal has been completed, however, the line is again laced in its normal closed condition, so t at the relay R, agam'attracts its armature against its front contact as shown in Fig. 1. v

Let us now assume that a break occurs in the line at some point Q. Relays R and R, will then be deprived of current, thus allowing their armatures to fall against their back contacts and close the buzzer and register circuits. The signal lamp will glow and the register and buzzer will operate continuously until the trouble has been temporarily overcome. This may be done by changing the position of switch S from the left to the right. This changes the local circuit so that the register is connected to the front contacts of both relay R and R, and at the same time applies battery to the end of the line which was formerly grounded atG. Now when any call box such as B,

is operated, the break wheel applies a round to line L, and causes currentto flow in that particular portion of the lineand through the relay R The armature of relay R, is then drawn against its front contact, causing current to flow from the source E, through the front contact and armature of the relay R switch S points-8 and 3 of switch S, and the register D, thus causing the register to record the signal on the tape. As either relay will now operate the local circuit it will be seen that the o eration of a call 'box on the other side 0 the break will also repeat the signal into the register.

Now let us sup ose that instead ofbreaking, the line' had become accidentally grounded at the point Q. .So long as the switch S remained in its left hand position,

that portion of the line containing the call boxes B B and the relay B, would be deprived of current, thus causing the armature of rela R to fall against its back contact and c ose the local signal lamp and buzzer circuits. Buzzer Z willthcnbuzz continuously'and signal lamp SL will remain lighted until the trouble has been temporarily overcome. This may be done by changing the position of the switch S from the left to the right and throwing switches S, and S downward. The changing of these switches applies battery to both ends of the line and at the same time changes the local circuit connections so that the front contacts of the relays R and R are disconnected, while their back contacts are connected to the register. Each portion of the main line circuit and the rela included therein operate independently o the other, each relay responding only to "signals sent from call boxes included in the portion of the line between that relay and the ground. Now when any call box is operated, that portion of the circuit is broken a number of Aglain let us suppose that a break occurs in t e line on one side .of the accidental ground which already exists at the point Q, leaving a portion of the lineL open, while the other portion L remained grounded. The switch S should now be thrownin the upward position, in order to change local circuit connections from the back to the front contact. Each relay now responds only to such calls as are sent from call boxes included in that portion of line between that relay and the break or ground. The operationof the portion of the line L is the same as explained above for a break at Q, and the operation of the portion'of the line L is the samev as explained in the last paragraph. If the open had occurred-on the other side of the ground, the switch S would occupy manipulation of three separate switches in various ways until some arrangement of the switches is found in which the signal lamp is extinguished, the buzzer silenced and the register magnet is not energized. l or the purpose of reducing the switches to a single operable device which will automatically cause the circuit changes required to maintain service when a fault exists and which lllfi will also indicate by the position of the parts, the nature of the particular fault, I have devised a switch mechanism illustrated in Figs. 2, 3 and 4.

This trouble indicator and circuit changing switch comprises several series of concentrically arranged segments and a plurality of switch blades secured to a rotatable central stem or shaft by which they are simultaneously moved over said segments.

The circuits of the messenger call box system' shown in Fig. 2 will be readily understood from the previous description of Fig.

1, like parts being designated by the same reference characters. T

The blades may each consist of a plurality of superposed spring leaves extending radiand FR,.

The switch blade S contacts with and is BR,

movable over the two' outer segments and Z, the former being connected to the back contact or relay R and Z the latter being connected to the signal lamp SL. The intermediate brush S'fextends in opposite directions from the central shaft, its outer bent down edges moving in contact with i the middle circle of segments which are connected as indicated to line, battery and ground, respectively. The inner brush S, movesover the inner circular series of segments and has its bent down margin of a width sufficient to simultaneousl contact with four adjacent segments. he segments, marked Z are connected to the signal lamp, those marked FR are connected to the front contact of relay R,, those marked BR to the back contact of relay R those marked HR, to the front'contact'of relay'R,, those marked BR, to the back contact of relay R and those marked d to the register D.

It will be evident that when the blades of the circuit changing switch are in the normay position indicated in Fig. 2, and both of the relays R, and R are energized,'the circuits from the front contacts of the relays are open at the switch segments F R \Vhen one of the call boxes B, 13,, B. etc., is operated, each time the code wheel opens the circuit the armature of relay R, moves over against its back contact and closes a circuit through the register D from source E through conductor 12, armature and back contact of relay R conductor 13, segment BR switch blades S segment d, conductor 14 toregister I) and ground at G Relay R is also deenergized and its armature closes a circuit through signal lamp SL from source E armature and'back'contact of relay R conductor 15 segment BR switch blade S segment land lamp SL to ground at G. It will be evident that the pilot relay PR and buzzer Z shown in Fig. 1 may also be connected in the ground connection from the signal lamp if desired. When the code wheel of a call box makes a ground connection the relay LR will be energized from the source E but the ground at the box shunts the relay R and hence at each ground contact of the code wheel, the armature of relay R moves against its back contact and closes the circuit above traced through the signal lamp.

As previously described in connection with Fig. 1, if a break occurs in the line at some point as Q, the relays will be deprived of current thereby allowing their armatures to fall back against their back contacts and close the signal lamp and register circuits and these Wlll operate continuously until the trouble has been temporarily overcome.

This may be accomplished by turning the shaft Yof the switch around by means of a thumb nut, dial member or other means fastened-to the j shaft. As the shaft is rotated so that the, blades move from normal position showninFig. 2 to the second position and again to the third position, as indicated in Fig. 3,"the signal lamp will'continue to glow,'thus showin that the trouble still persists. VVh'en the lades are moved into the fourth position, the I lamp will i be extinguished and the operator will thereby know that the circuits have been temporaril shifted or adjusted to overcome the fau t and the signals willbe received in themanner as if switch S in Fig. [were thrown to right hand position and switches S and S were in their upper positions. The operator will also know by the position of the switch that the fault is an open line. In

practice the designation of the nature of the faults corresponding to the several positions of'the switch are indicated on the handle-or on the face of the switch casing. This switch therefore indicates the nature of the fault in addition to adjusting for the fault condition.

If instead of being open, the line had been grounded, the lamp SL would have been extinguished when the switch was turned to the second position. Likewise if the line had been open and also grounded, the fault would have temporaril overcome when the circuits were connecte in the arrangement provided by the switch in the third position. The circuits for the several positions of the switch may be readily traced from an inspection of Fig. 2. i 7

Upon the repair of a ground fault, that fact is indicated at the'central station by the lighting of the signal lampand the operation of the register.

As shown in Fi 4, the stem Y-of the switch carries" a circular block havin a lower serrated or notched surface whicl i engages the upper correspondingly notched or serrated surface of a block 21 secured tothe base of the switch. These blocks are yieldingl held together b any suitable means. or this purpose,1 ave shown the stem extending throu h an a erture in the base and surrounded y a spiral spring 23. The serrations are so dimensioned and posi-' tioned that the switch blades are in one of the switching positions whenever the teeth of the blocks are in mesh as shown. The spring always moves the blocks into meshing position whenever the knob or fingeriece on the end of the stem is released.

henever the switch stem is turned to change the position of the switch blades the serrations exert a wedging action to lift the blades from contact with the contact segments and-hold them suspended as the segments move across each other and then per-- wit the blades to descend and contact with the segmentsat the next succeeding-switch position. This construction ensures the ac-: curate positioning of the blades and also ensures a pressure engagement ofthe blades upon the segments whenever the stem is released by the hand of the operator, Iclaim: I

1. In a signaling system having outgoing and return lines forming a closed circuit containing a plurality of signal transmitting devices having contact mechanism for controlling the circuit and also for connect- I ing it to ground, a current source havin one terminal'normally connected togroun and the other terminal connectedto one side .of said circuit, relays includedin opposite sides of saidcircuit, signaling devices controlled res" tively by said rela s, and a unitary switch device having a p uralit of segments connected .to thet'ront and k contacts of said relays, to the grounded end of the line and to said signaling devices,

and provided with a rotary shaft and blades movable thereby to different positions to interconnect said segments in a manner to cause the signals from said signal transmittin devices 'to be received, when the line is in normal condition or is open, or o and grounded, or grounded, or groun d and open. i I

2. In a signaling system having outgoing and return lines formin a closed circuit containingv a plurality 0 signal transmitting devices having contact mechanism for controlling the circuit and also for connecting it toground, a current source having one terminalnormally connected to groun and the. other terminal connected to one side of. said circuit, relays included in opposite sides of said circuit, signaling devices controlled respectively by said relays, and a unitary switch device having a plurality of segments connectedto the front and back contacts of said relays, to. the grounded .4. In a'signaling system and return lines forming a closed circuitend of the line and to said signaling devices,

and provided with a rotary-shaft andblades movable thereby to different positions. to

interconnect said segments in a manner to indicate, in cooperation w th said s gnaling devices, when the hne ls 1n normal cond1-.

tion or is open, or open and grounded, or

grounded, or grounded and open.

3. In a signaling system having outgoing and return lines forming aclosed circuit containing a plurality of signal transmitting devices having contact mechanism for controlling the circuit and also for connecting itto ground, a" current source having one terminal normally connected to ground, and the other terminal connected to one side of said circuit, relays included in opposite sides of said circuit, signaling devices controlled respectively by said relays, and a unitary rotary switch deviceinterconnected with said rela s and said signaling" devices 7 and rotata le to difierent positions to permit the reception of signals when theline is innormal condition, or is open, or open and grounded, or'grounded, I

or grounded and open. I v having outgoing containing a plurality of" signal transmitting devices having-contact mechanism for controlling the circuit and also for connect- I ing: it to ground,-a current source havin one terminal normally connected to groun and the other terminal connected to 'one'side of said circuit, relays included in opposite sides of said circuit, signaling'devices controlled respectively by said relays, and a GEORGE W. fJANsoN.

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