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Publication numberUS1148931 A
Publication typeGrant
Publication dateAug 3, 1915
Filing dateJan 12, 1915
Priority dateJan 12, 1915
Publication numberUS 1148931 A, US 1148931A, US-A-1148931, US1148931 A, US1148931A
InventorsIsrael E Rosenthal
Original AssigneeIsrael E Rosenthal
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
US 1148931 A
Abstract  available in
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Claims  available in
Description  (OCR text may contain errors)




Application filed January 12, 1915.

-State of Arkansas, have made certain new and useful Improvements in 'Circuit-Closers, of which'the following is a specification.

My invention is an improvement in circuit closers for electrical fire alarms, and has tor its object to provide a simple, inexpensive and eiiicient device of the character specified, operated by excessive heat for automatically closing an electrical circuit to cause the same to; actuate an alarm or a series of alarms, as for instance bells, automobile horns, electric whistles and annunciators. i

In the drawings: Figure 1 is a diagrammatic View of the improved circuit closer in use, Fig. 2 is a section on the line HL-2 of Fig. 3, and Fig. 8 is a section on the line 3-3 of F ig. 2, both Figs. 2 and .3 looking in the direction of the arrows adjacent to the respective lines.

The improved circuit closer is interposed in an open electrical circuit, comprising a suitable source of electrical energy, as for instance a battery 1, and lead wires 2 and 3 lea-d lfrom the opposite poles of the battery to the mechanism to be later described.

The improvement is especially designed for use in connection with the safeguard life and telephone attachment forming the subject matter of my U. S. vPatent- No. 1,113,052, granted to me on Oct. 6, 1911, the said attachment being designated generally at 4, and the lead wire 2 is connected with one of the binding posts 5 of the said attachment. A continuation of the lead wire 2 designated at 2f1L leads from the other binding post 7 of the attachment'to the circuit closer forming the subject matter of the present application, and the lead wire 3 is also connected with the said circuit closer.

It will be understood that as many of the circuit closers may be used as may be desired, and they may be arranged in different rooms, or in diii'erent places in the same room, or in diii'erent buildings and preferably they are connected with the ceiling at the point which it is particularly desired to safeguard against fire.

Each of the circuit closers is composed of a metal box, consisting of an open rectangular frame 8 of metal, and the frame is seamless, and no solder is used in the forma- Specic'ation of Letters Patent.

Patented Aug. 3, 1,915.

Serial No. 1,887.

tion of the frame. The box is completed by heads or end plates 9 andv 10 respectively, the said plates being of the same metal as the frlame 8. A .wood screw 11 is passed through an opening in one side of the fra-me, the said side being hereafter designated as the top, and the wood screw is adapted to engage a fixed support designated at 12, in the place which it is desired to safeguard against fire. The heads'9 and 10 fit against the ends of the frame, and each head is provided on its inner face with tour inwardly extending lugs or bosses 13, formed in the present instance by embossment, that isby stamping or pressing inward a portion of the material of the head, and the said bosses are in such position that they will guide in the placing of the heads, that is the said lugs or bosses fit within the frame properly positioning the head with respect to the frame. 4The heads are held in place by a sectional screw, consisting of an inner sec tion 111 and an. outer section 4a. Each section isprovided with ahead, having a 'transverse kerf for engagement by a screwthe bottom, and other binding posts 16 and 17 are connected with the heads 9 and 10 respectively. vThe binding post l5 is connected to the frame directly, while the binding posts 16 and 17 are insulated from the respective heads, by means oiiwashers 18 of insulating material arranged on .OPPOsite sides of the head, one of the washers havingv an axial, extension passing through the opening in the head through which the binding post extends.

A coil spring 19 is connected with the binding post 16, and a similar spring 20 is connected with the binding post 17, one end of each spring being held between the head of the screw that connects the binding post to the head and the adjacent insulating washer 18, and the said springs are of a length to extend nearly through the frame,


that is nearly to the opposite head. A screw 21-is connected with the inner end of the spring 19, the coils of the spring at the end remote from the binding post being of a smaller size' than those between the binding post and the outer end of the spring, that is being reduced to lit the screw, and the screw is arranged with the head extending in the opposite direction to the binding post. A similar screw 22 is connected with the spring 20 in the same manner, and the head of each screw is covered by a sheath, shield or hood 23 and 24 respectively of easily fusible material, as for inst-ance wax. Directly opposite the binding post of the other head each head is provided on its inner face with a depression 29, formed by stamping or embossing the metal, the said depression being designed for engagement by the sheath or hood of the other binding post. The coil springs 19 and 20 are of such length that when the heads are clamped on the frame, the sheath or hood of each binding post will be pressed firmly against ,the bottom of the depression of the opposite head.

As before stated one of the lead wires, 3 in the present instance, of the open circuit is connected with the binding post 1.5, that is with the frame. The other lead 2 or its extension 2EL isconnected with the binding post 16, that is with the head 9, and another lead wire 6 leads from the binding post 17 of the head 10 to the lead wire-2, upon which the said wire is branched. Alarms, as for instance horns, indicated at 25, electric bells, indicated at 26, or annunciators, indicated at 27 may be interposed in the length o f the lead wire 6 either in parallel as shown for the horn 25 and the annunciator 27 or in series, as shown for the bell 26.

The attachment forming' the subject matter of my above-mentioned patent is designed to be arranged adjacent to a telephone, beneath the hook that supports the transmitter, and the arrangement is such that when the circuit in which the attachment is interposed is closed, a slide will be released, and the slide will be forced upward by a spring and will engage the hook, and will sound the alarm by means of the, telephone at any desired place, as for instance the nearest fire station, or a watchmans room. The attachment is also provided with an electrically operated bell 28 actuated by the closing of the circuit that releases the slide. The annunciator 27 may be placed in the fire department station, or in the j anitors oliice, or in a watchmans room, and it will be understood that the annunciator is connected with the different circuit closers, to indicate therespective closer that has been acted upon by excessive heat to close the circuit.

With a single circuit closer of course an annunciator is not required, but where several closers are used the annunciator is necessary to quickly indicate the particular location of the fire.

In operation, when the circuit 'closer is exposed to heat above a predetermined quantity, the interior of the box will become heated, and one or more of the sheaths or hoods 23-24 will melt, permitting the head of the screws 21 or as the case may be to contact with the opposite head 9 or 10 as the case may be. If only the sheath 23 is melted the circuit through the attachment 4 is closed, thus causing the attachment to lift the hook of the transmitter and thus sound the alarm. In addition the circuit through the lead wire 6 is closed, andthe horns or the bells 26 are actuated to sound the alarm while the annunciator 27 is operated to indicate that circuit in which the alarm is sounded. In the first instance, that is when the attachment 4L is actuated, the current passes from the battery by way of the lead wire 2, through the attachment 4, by way of the lead wire 2a, to the binding post 16, and through the spring 19 to the head 10, the frame 8, the binding post 15, and the lead w-ire 3 to the battery.

It will be noticed that the free end of the strand of wire which forms each spring 19 and 20 is extended radially or at an angle from thespring, for a considerable distance,

and the free end or extremity of each extension 30 is flush with the head of the adj acent screw or beyond the same, but not beyond far enough to engage the opposite head until the sheath of wax is melted from the head. This extremity 30 of the spring assists in making a good electrical connection between each binding post and the opposite head. The depressions 29 in which the sheaths 23 and 24 of the screw heads are received prevent displacement of the loose- ,end of the fuse, these elements constituting the fuses that melt to complete the circuit.

The lugs or bosses 13 insure the proper placing of the head, and the state of the fuses may be easily inspected by loosening the sectional screw. The bosses formed on the outer faces of the heads bythe depressions 29 also act as guides for the proper placing of the heads. By means of the wood screw 11 the circuit closers may be arranged in any desired location.

It will be noted fromV an inspection of Fig. 3 that the socket in the section 14'* of the double screw is not threaded throughout its extent, only the inner end being threaded and the inner end isof less diameter than the outer end. Thus the plain portion of the socket serves as a guide for the insertion of the threaded end of the section 14. y

I claim:

1. A circuit closer comprising a metalv box consisting of an open frame and heads f connectingfthe heads-'and clamping vthem on the ends of theframe, a screw connected a bindingfpost connectedvwith the* frame'at theopposites ide, a binding post connected with each head and insulated therefrom, a .and having at the other end a fusibleshield vcoil .-spring''for the bindingpost of each springbein'g connected atone endA to one of.

the binding posts and vinsulated from thebox, andfa protecting hood lof fusible nonconducting material on the outer end of each" Y headandfwithin theframe, each springbe-v ing connected .at one end to the binding post and insulated from the box, a screw` con-'- Avnecte'd'with the opposite end of each lspring and having-its head extending 'infthe opposite directionto the. binding post, a coating of fusiblel nonfconductin'g material protecting' the headofeachscrew and engaging the to cause' the screw to contact. with the head 512. A' circuit closer ycomprising. 'a'l metal box consisting of an open frame and heads for closing the` ends -of the frame,` a screw vconnected with one Wall of the frame for engaging a fixed support to suspend the circuit' closer, a bindingpost connected Withtherefrom, a coil spring for the binding post of each head and vWithin thev frame, each spring and engaging the opposite head and adapted to melt under the influencel of heat to permit"{the spring "toy engagethe'head y directly, and means lfor clamping theheads on' the frames. v v

3. A circuit closer-comprising ametal box,v

consisting of a frame and heads fitting the ends of-the frame, detachable means for clamping the heads onthe ends of the lframe,

opposite `head, each head having adepres-v "sion for receiving -the screw4 connected -to the 'p otherV head, Vand-.the spring being designed :if Whenfthe fusible material f ismelted, each spring 'having-ajradi-a-l extensionat the end' vadjacelit tothe screw for engaging the -op-fposite head when Ithe fusib'1e -material-:is

.melted f .to permit the means at one side of the frame'fbr connecting the fra me to a fixedsupport, a binding vpost connected -With the other side of the frame, 'a binding postconnected with each head and insulated'therefrom, and a coil springconnected `at one end with the bind-f ing post of each head-and Within `the box the infiuence of heat to permit the'spring to engage the head directly, each spring having a radial 4extension at the end adjacent to the plug and a lsupport for the plug or .shield connected With the spring.

"of" non-conducting 'materialiengaging the opposite head and adapted tov melt under -c1amping the heads on the ends of the frame, i*

Ameans* for connecting the frame to a fixed support, .a'binding post connected With the frame, ,a binding post connected With each headV and insulated therefrom, and a coil spring connected at one end With 'each of. vthe last named binding posts Within the box and having atfthe other end a fusible-shield of non-conducting mate-rial engaging' the opposite head and adapted to melt under the influence of heatA to permit the spring to engage the head directly.

5. A circuit'closer comprising a metal box composed of a frame and heads vat the ends. of the frame, a binding post connected W'ith `the frame, a binding post connected Vwith each head Vand insulatedtherefrom, a spring connected at one end with each of'the last named binding posts within the box and eX- tending toward the opposite head and havfing a shieldoffusible non-conducting Ina-v terial forengaging said opposite head andA adapted'to melt'under the influence of heatv v rectly."

spring to engage the head di lsinner", RosENTiiAL.

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US4058014 *Jul 16, 1976Nov 15, 1977Caterpillar Tractor Co.Maximum temperature range indicator
U.S. Classification337/406, 337/413
Cooperative ClassificationH01H39/00