US1990569A

US1990569A - Signaling system

Info

Publication number: US1990569A
Application number: US497133A
Authority: US
Inventors: John B Shiel; Albert G Lang
Original assignee: Bell Telephone Laboratories Inc
Current assignee: AT&T Corp
Priority date: 1930-01-06
Filing date: 1930-11-21
Publication date: 1935-02-12
Anticipated expiration: 1952-02-12

Description

Feb. 12, 1935.

J. B. SHIEL ET AL SIGNALING SYSTEM Original Filed Jan. 6, 1950 MARG/NAL J. asH/a A T TORNE'V Patented Feb. 12, 1935 UNITED STATES;

PATENT OFFICE 1,990,569 SIGNALING SYSTEM John B. Shiel, GlenHead, and Albert G. Lang, Whitestone,N. .Y., assignors to Bell Telephone Laboratories, Incorporated, New York, N, Y., a

corporation of New York :Original application January 6', 1930. Serial No. 418,893. Divided and this application November 21,1930, Serial No. 497,133

2 claims. (or. 177 3521 This in'vention relates to signaling systems wherein signaling circuits are controlled by an interrupter and more particularly to means asso' ciated with the interrupter connecting circuitto 5 cause analarm to'be given and an emergency arrangement brought into service to control the signaling circuitswhen an abnormal or unstandardi condition exists on the connecting circuit.

- This application is a division of abandoned; ap-

plication SerialNo. 418,893, filed January 6,1930

forimprovements insignaling systems.

In" accordance with the feature of the invention the interrupter is normally connected to a. dis-'- tributing circuit which in turn is branched out to anumber of signaling circuits or loadfcircuits required to be intermittently grounded through a corresponding plurality of contact pairs. When an abnormal or ,unstandard condition arises the normal connection between the interrupter and the distributing circuit is broken and p the emergency arrangement is brought into play; The emergency arrangement controls each line individually by means of said contact pairs thereby achieving the same result as the 'normal interruptercircuit in a different manner; Through this arrangement, 'anabnormal condition present on a particular signaling circuit which before'the' switching takes place would be communicated to pulses fiow through the back contact and armature of relay 3 to conductorf i here termed the distr-ibuting circuit. 'Ihec distributing circuit is i connected-through the 1 armatures and back contacts of a plurality of relays5, 6 and 'Tto a plurality ofv occasionally energized signaling circuits such-.as.8,i9' and 10. Circuits 8, 9 and 10 may be :any circuits which are required to be intermittently grounded. Such circuits are well known in the art as, for example; seethe patent to Potter 1,479,555, issued January 1, 1924, which shows interrupter leads I whichcorrespond to the V 7' leads 8, 9, etc. of the present application.

The interrupter circuit 2 is connected through the normal contacts of a key 11 to the winding of a relay'12. This relayresponds'to the interruptions and constantly vibrates its armature. If

the impulses supplied by the interrupter are at the rateof-40 or 60 interruptions per minute, then the armature of relay '12 will bemoved between its frontand-its back contact at the rate of lfl or 60 times per minute; 1,

During the periods that the armature of relay 12 is resting on its front contact, a' circuit is closed forrelay l3 and this relay being slow to release maintainsits armature in its operated position so long as relay 12 is constantly operating as described.

' In the same manner, when the armature of relay 12 is resting on its back contact a relay-141s energized and this also being slow to "release, maintains its armature inits operated position so;

long as relay 12 is constantly operating.

Through the constant energization of relays 13 and 14', a circuit is closed for relay .15 and this being slow to release will maintain its armature: operated even though relays l3 and 14 should mo:-

mentarily release.

The conditions above described are normal and.

will be maintained so long as interrupterloperates properly and the circuit 2 is maintained in a standard condition;

Let, it be assumed that conductor 2 becomesopened near the interrupter l or at any place between interrupter 1 and key 11;. then relay 12 will cease to operate and its armature will rest steadily on' its back contact. Undertheseconditions relay. 14 will be maintained energized but in a short interval relay 13 will become deenergized. Thereupon the circuit for relay 15 will be opened and this relay will allow. its armature to return to normal. The result'of this will be described in detail hereinafter.

Let it now be assumed that the conductor 2' becomes grounded. In that case, relay 12. will become steadily operated and its armature will. rest constantly on its front contact. Under these.

conditions relay 13 will bev maintained energized, but relay 14 willrelease, and after a short,

interval as before, relay 15 will return its armature to normal.

' The-grounding of conductor 2 may take place. either on the conductor, 2 itself, on the distributing circuit 4, or on any one of the signaling circuits such as 8, 9 or 10.

It should be particularly noted that in the case,

where one of the signaling circuits such as 8 becomes permanently grounded, that this ground.

under these normal conditions will be communicated to all the other signaling circuits such as 9 and 10 and will therefore put them out of commission, It should be further noted that relay 12 may be held operated by a ground through aresistance so that by proper design, relay 12 may be made to respond to any ground condition on a signaling circuit which would tend to disrupt the service.

It will thus be seen that when either the interrupter circuit 2 is opened between the interrupter 1 and the key 11, or such circuit is grounded, that relay 15 will return to normal.

Upon this occurrence, a circuit will be established from ground, the armature and back contact of relay 15, winding of relay 16 to battery. Relay 16 becomes energized and locks in a circuit from ground, key 17, front contact and lefthand armature of relay 16, winding of relay 16 to battery. Through the operation of its righthand armatures, relay 16 first closes a circuit from ground the innermost right-hand armature and front contact of relay 16, alarm 18 to battery. At the same time a circuit is closed from ground, outermost armature and front contact of relay 16, winding of relay 3 to battery. Relay 3 becomes operated and disconnects the interrupter circuit 2 from the distributing circuit 4 and permanently grounds the distributing circuit over the front contact of-relay 3.

Thus, upon interruption of the service over interrupter circuit 2, alarm 18 is operated and the, distributing circuit 4 is permanently grounded.

At the same time the ground for operating relay 16 is communicated to the visual alarm 19 and this operates steadily. v 7

Through its middle right-hand armature, relay 16 places a ground on conductor '20. This ground finds ,a circuit through relay 21 and resistance 22 to battery whereupon relay 21 becomes oper ated. Upon the operation of relay 21 a shortcircuit about the winding of relay 23 is opened and this relay now becomes operated in series with resistance 24. In the same manner, upon the operation of relay 23, a short-circuit about the winding of relay 25 is opened and this relay in turn becomes operated in series with resistance 26. Relay 25 in operating now closes a shortcircuit about the winding of relay 21 and after a short interval relay 21 becomes deenergized. When relay 21 returns to normal, it in turn shortcircuits relay 23 and relay 23 in turn short-circuits relay 25. This cycle of operations occurs periodically.

Upon the first operation of relay 25, a circuit is closed from ground, the outer right-hand armature and front contact of relay 25, the left-hand armature and back contact of relay 27, winding of relay 28, left-hand winding of relay 27 to battery. Relay 28 operates in this circuit but relay 27, being marginal, fails to operate. Upon the operation of relay 28, a circuit to the right-hand winding of relay 27 is closed but this only results in short-circuiting such winding, since a ground is to be found on conductor 20 which is communicated through the armature and front contact of relay 28 to one side of the right-hand winding of relay 27, the other side being grounded through theouter right-hand armature of relay 25.

Upon the following release of relay 25, the short-circuit about the right-hand winding of relay 27 is removed and now relay 2'7 becomes operated in a circuit from ground, the middle right-hand armature and front contact of relay 16, conductor 20, armature and front contact of relay 28, right-hand winding of relay 27, winding of relay 28, left-hand winding of relay 27 to battery. Relay 27 now operates its armatures and prepares acircuit wherein relay 28 will become deenergized. As soon as relay 25 again becomes operated, a ground is connected directly to the left-hand winding of relay 27 and the Winding of relay 28 and the right-hand winding of relay 27 in series therewith are short-circuited. Relay 28 becomes deenergized and relay 27 holds.

Upon the next deenergization of relay 25, relay 2''! releases.

Thus it will be seen that for each two complete cycles of operation of relay 25, relay 27 will go through one complete cycle of operations.

Upon'each energization of relay 27 a circuit is closed for relay 29. This relay becomes operated and places a ground on conductor 30 which is communicated in parallel to each of the relays 5, 6 and 7 and to signal lamp 31. The design and adjustment of

relays

21, 23 and 25 is such that the rate of operation of relay 29 and consequently the periodic application of ground to conductor 30 is the same as the rate of interrupter 1.

Now since the distributing circuit 4 is permanently grounded at the front contact of relay 3, each of the signaling circuits 8, 9 and will be grounded during the deenergization of relays 5, 6 and 7 and the result is that the signaling circuits are intermittently grounded as before.

It should be noted that now even though a particular signaling circuit such as 8 becomes permanently grounded, that this ground cannot be communicated to the other signaling circuits during the operation of the emergency interrupter

circuit comprising relays

21, 23, 25, 27, 28 and 29.

An attendant noting the steady illumination of signal 19, the intermittent illumination of signal 31, and the alarm 18, may by pressing key 17, restore the circuit to normal by allowing relay 16 to become deenergized. If the trouble which occurred was of a temporarynature and has been righted by this time, relay will be in its energized condition and when key 17 is pressed, the circuit will assume its normal condition and begin to operate properly. If, however, the circuit is of a more permanent nature, then when the key 17 is restored, the alarm 18 and the signals 19 and 31 will again operate and the trouble will.

have to be traced and properly adjusted. When the trouble is cleared, the circuit may then be restored to normal by a momentary depression of key 17.

What is claimed is:

1. In a signaling system, a plurality of electric signal devices each having two terminals, means for connecting a source of operating current to one terminal of any one device, a plurality of signal conductors individually connected to the free terminals of said devices, an interrupter lead, an interrupter adapted to periodically connect ground thereto, a permanently grounded lead, a multi-contact relay normally connecting all of said signal conductors to said interrupter lead, means for periodically operating said relay, other means responsive to a steady ground condition on said interrupter lead for disconnecting said interrupter lead from the contacts of said relay and substituting for said interrupter lead said other permanently grounded lead and for initiating the operation of. said means for periodically operating said relay to periodically disconnect said permanently grounded lead from said signal conductors.

2. In a signaling system, a common lead, (4), a plurality of individual load conductors (8, 9, etc), signaling devices associated therewith and adapted to be operated thereover, an interrupter lead (2), means (1) associated'therewith for intermittently connecting ground thereto, means (3) normallyconnecting saidcommon lead (4) to said interrupter lead (2) and adapted to be actuated to disconnect said interrupter lead (2) from said common lead (4) and to connect a steady ground to said common lead (4) a multicontact relay (5) normally connecting said common lead (4) to said load conductors (8, 9, etc.) in multiple, auxiliary means (21, 23, 25, 27, 28

and 29) for intermittently'operating said multicontact relay (5), relay means (16) responsive to a ground condition on said interrupter lead (2) for a, predetermined period longer than the ground condition intermittently applied thereto by said first means (1). to actuate said second means (3) and to initiate the operation of said auxiliary means (21, 23, 25, 2'7, 28 and 29).

7 JOHN B. SHIEL.

ALBERT G. LANG.