US1720738A - Signaling system - Google Patents

Description

July l5, 1929 A. LE BOUTILLIER Y A 1.720.738 I SIGNALING SYSTEM Filed Dec. 16, 1926 MA RGV/VAI Patented July 16, 1929.

11 UNITED STATES 1,720,738 PATENT oFFIcE.-

AUSTIN LE IBOUTILIiIER, F WESTERN SPRINGS, ILLINOIS, ASSIGNOE, TO WESTERN ELECTRIC COMPANY, INCORPORATED, OF YORK, N. Y., A CORPORATION OF NEW YORK.

SIGNALING SYSTEM.

Application led December 16, 1926. `Serial No. 155,216.

' This invention relates to a signaling system, and more particularly to a signaling system yfor indicating a current failure in A, l a leadv of a supply circuit.V An object of the invention is to provide a signaling` system` which `will indicate when jan electrically operated Adevice is not operating atA its highest 'eificiency. Y i The inventioncontemplates the provision of means associated with each of a plurality offleads of asupply circuitV to indicate when Aa total orpartial/failure of current loccurs therein. Inaccordance with one embodiment, a series transformer is placed in each of the leads ,of a supply circuit to indicate fa failurevof current therein anda relay responsive to the currentin the transformer for operating a signaling circuit isconnected across theterminals ofa coil of a magneti- 2cally operated switchin the supply circuit vto prevent an indication in the signal element -whenthe coil is deenergized and the current infa predetermined numberV of leads is'interrupted bythe normal operation ofthe switch. 2 Itis believed that a complete understanding of theinvention may be had by reference to the .following description taken in conjunction with the accompanying drawing, in which asignaling system is diagrammatical- 3.0 `1y 4represented as applied to an' electric annealing furnace. y c

Referring to the drawing, a three phase line of alternating current 3, 4, 5 is shown leadingthrough a main switch 6 through `fuses 7, 8,l 9 to the primary of a transformer 10 which is provided with three secondaries `11` 12, "13 whichY supply'secondary circuits 14, `15and 16, respectively. The secondary circuits lead to deltaV connected heating ele- A ments 17, 18` and 19 of any suitable type which may bke-associated with an electric annealing furnace. AIt is customary in furnaces of vthis type to provide a plurality of heating-elements which are located in vario ous parts ofthe furnace. The heating `element 17 in the present instance is diagrammatically represented as'connected to the `seconda-ry circuits through movable elements such as `shoes V21 engaging tracks for the Lreason that one of the heating elements is in many instances located in the car in which @the material to be annealedis carried into the furnace.r Y f f The-secondary circuits 14, 15 .and 16 are provided with'switches 2 2, 23 and 24 which are operated by electro-magnetic coils 25,l 26 and 27, respectively. "The coils are energized by means'. of a transformer 28 which is connected across conductors`4 and 5 ofthe primary circuit. In the vicinityof the heating elements 17,' 18 and 19 in the furnace thermocouples 31, 32 and 33 are located which operatc pyronietric control switches 84, 35 and 86, respectively, in the'circuits of the niagnetic switches 25,26 and 27. Whenever the temperature in the vicinity of a given heating element rises above 4a predetermined value ,the corresponding pyrometric control switch willbe opened which willresult in the opening of the switch in the secondary of the supply circuit until the temperature has dropped to a predetermined value when the switch will again be closed. A series transformer 37. is associated :with each of the conductors leading to the heating ,elements and has in circuit therewith a relay 38 having normally lclosed contacts. The relays are arranged in groups of three comprisingV three groups 41, 42 and 43, and each group is connected across the terminals of a coil of the secondary switches 25, 26 and v27, re-

spectively.` The groups 41,42 andl43 have also in circuit therewith relays 44,45 and 46 of a signal circuit having normally opencontacts. The signal ' circuiticomprisesftwo conductors 47 and 48 which are connected in par-4 j allel to a bell 49andwa signal lamp 51, and

one of the conductors'has a direct current source ,52 in series therewith so that whenever a contact is madeb'etween the two conductors the bell and lamp will produce a signal.

Therelays `in circuit with the series transformers may be so adjusted that when the current in a conductorbecomes. less than a predetermined amount, the contacts of the relayy associated therewith will be permitted to close, establishing a circuit through one of the relays '44, 45 and 46 depending upon the group in which the contacts-of theA relay were closed,` thereby closing the signal circuit and producing asignal. It `will be seen that whenever-one of the secondary switches 22, 23 "or .24 is opened, the currentV in the corresponding secondary leads will be interrupted and the contacts of relays associated therewith willbe closed. However, the norl mally open relay in the signal circuit will not the reason that themsecond-v be voperated for sistance contact in the circuit or the burning out of one ofthe heating elements of the furnace.

The signal circuit is also adapted to be `operated when one of the fuses inthe primary circuit is destroyed. For thispurpose a relay 54 having normally open contacts is provided which is connected across the terminals of the fuse 7 in theline 3i. so that when the fuse/in this line is destroyed the relay will be subjected to the line voltage closing the relay andv operating the signal circuit. If either of the fuses 8'01 9iis destroyed, the voltage applied to the-transformer 28 is reduced to one-lialf the normal voltage, which is insufficient to operate a relay 55 causing its normally closed contacts which are maintained in an open position while the relay is energized to close and operate the signal circuit. In order to operate the apparatus it is merely necessary to close theI primary switch 6 and; then close a switch 56 inthe signal circuit. The closing of the primary switch will energize the transformer 28, closing the secondary circuits by means of the magnetic switches. Vhen the transformer 28 is energized, the relay 55 is energized completely opening the signal circuit until such a change in the operating conditions of the apparatus occurs as'will causeV a signal.

push button 'switch 57 is provided in the signal circuit to test the signal devices for the ,purposey of;v determining whether "they are'in proper operatingA condition.

In addition to the series transformers associated with the secondary leads, a series transformer 60 may be associated with each branch of the delta connected heating elementsi'n the furnace as shown. It is customary to bring the leads of all the heating ele` ments of al furnace to the exterior and make the delta connection there, so that the series transformers may be conveniently connected with each branchof the heating elements of f the furnace. The series transformers when used are Connected in circuit with relays 61 which comprise two groups 62 and 63' which are connected in parallel with groups 42l and 43, respectively. The operation of a relay in group 62` orr63 will therefore have. the

same effect as the operation of a relay in the respectiveparal-lel group 42 or 43. v When the additionaltransformers are used the. accurate adjustment of the relays in circuit with the series transformers in the secondary leads is not necessary and the latter may be so adjusted as to indicate only a complete current failure in the lead.

It will be understood that the embodiment of the invention herein described and illustrated is merely a convenient and: useful form of the invention which is capable of many other modifications without departing from vthe spirit and scope of the invention.

`Whatis claimed is:

1 A signalin system for a supply circuit having aL plura ity of leads divided into a plurality of groups, a switch for each group of leads, a transformer associated with each ofthe leads, said transformers being arranged ingroups correspondingto'I the switches, a signalcircuit, al relay associated with each group` of transformers yto energize the signal lcircuit in response to predetermined5 low currentconditions-in a'leadof'that group, and means to prevent the relay from energizing thesignal circuit when the switch of the groupis opened.

2. Aisignaling system for a supply circuit comprising a switch operated by a magnetic coil, a transformer associated with a lead of the supply circuit, a signalv circuit connected across the terminals of the magnetic coil-,a relay for operating the signalfcircuit, means for energizing the relayv when the current in the transformer'decreases to a predetermined lowvalue, and means for preventing an energizati'on offthe relay when the switch is open. 3. A signaling system for a supply circuit havingk a plurality of supply leads com rising a signal circuit, means for energizing t e signal circuit when. the current inonel of the leads decreases to a predetermined lowy value, andi means for preventing the energization of the signal circuit when the current in a predetermined number of the leadsisznormally interrupted but causing its energization when abnormally interrupted.

4. In a signaling-systemffcr a circuit for supplying a plurality. of heating devices, a plurality of'supplyleads for each of thefheating devices,va signal circuit, means for energizing the signal'circuit when the current-iin `oneV of? the leads decreases to a predetermined Ylio-w value, and means for'preventing the envmeans for interrupting the current in the leads of one of the heating devices in response to temperature conditions, and means for preventing the energization of the signal: circuit when the current in the leadsfoffV a heating device is interrupted in response to temperature erated devices in response to predetermined 10 conditions. conditions, and means for preventing the en- 6. In a signaling system for a circuit for ergization of the signal circuit in response to supplying a plurality of electrically operated the disconnection of the electrically operated devices, a plurality of leads for each of said device. devices, a signal circuit, means for energizing In Witness whereof, I hereunto subscribe my 15 the signal circuit when the current in a lead name this `third day of December A. D. 1926. decreases to a predetermined low value, means for disconnecting one of said electrically op- AUSTIN LE BOUTILLIER.

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