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Publication numberUS1891751 A
Publication typeGrant
Publication dateDec 20, 1932
Filing dateApr 2, 1932
Priority dateApr 2, 1932
Publication numberUS 1891751 A, US 1891751A, US-A-1891751, US1891751 A, US1891751A
InventorsDavid Coyne
Original AssigneeDavid Coyne
Export CitationBiBTeX, EndNote, RefMan
External Links: USPTO, USPTO Assignment, Espacenet
Electric circuit breaker and burglar alarm
US 1891751 A
Abstract  available in
Previous page
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Claims  available in
Description  (OCR text may contain errors)

Dec. 20, 1932. CQYNE 1,891,751


ATTO R N EY and all the electrical circuit Patented Dec, 20,



for use on fire escapes and other places where the apparatus is exposed to the action-of the weather. In substance the novel structure disclosed consists of a waterproof mat of elastic material having one or more cavities 19 therein, and a plurality of electrical contacts so arranged in each cavity that when themat is in normal shape the circuit will be closed, but when pressure is applied to the exterior of the mat at one or more points such cavity will be partly or wholly collapsed and at least some of the contacts therein contained so separated by the consequent deformation of the mat as to open the circuit and sound a remote V ly placed, electrically operated alarm of the Y type set off by the opening of its circuit. Such a concealed circuit breaker can also be placed at any desired point in the buildmg lnterior or in an'elevator or 111- a motor car, where it would blend with the surrounding furnishings or decorations so as to be entirely unobtrusive, but still be capable of convenient op eration by the foot,knee, elbow or other portion of the body, of aperson who is: being held up by a bandit or, for other reasons, de-

sires to send out an alarm without attracting the attention of persons present. The best form of apparatus embodying my invention at present known'to me is illustrated in the accompanying sheet of drawings in which F ig. lis a vertical longitudinal section on line l-1 of Fig. 2. p

Fig. 2 is a horizontal view from below taken on line 22 of Fig. 1, the bottom sealing sheet of the mat having been removed p 7 connections being also shown in diagram. i

Fig. 3 is a detail Vertical section similar to Fig. 1 on a larger scale showing a deformed portionof the mat.

' Fig; 4 is a perspective diagram showing an embodiment of the invention including a fire escape, and

Fig. 5 is a det il section showing a modification.

Iin the upper portion llof the Referring to the drawing, Iindicates :the

1932. Serial no. 602,681

NT oFFlcr. a I

mat, generally, in one face of which are i formed a seriesof recesses 2, 2. In the walls of each such recess in the embodiment of the nventlon shown in "Figs. 1, 2

and 3 are par-' tially embedded a series of electrical'contact members (preferably metal) in such manner that their projecting portions will normally be in contact so as to create a closed circuit through the series, but so set in the mat that when the adjacent portion :of the latter is deformed in such manneras to collapse the recess sufliciently, two or more of said contact elements will become separated and break the circuit at th atpoint. As there shown, these contact members; consist of'rivet-like structures, the shank's'3, 3, of whichare embedded matl inflpositions substantially radial to the curve of the surface of the wall recess 2, and near enough togetherso that their heads 4, 4, will then be in'contact. One outer element of each group is connected to one terminal ofan electrical circuitq5, while the other outer element is conne'ctedto the other terminal of such circuit which includes any etficient form of electrically operated alarm apparatus 6, adapted to go'into action whenever circuit 5 is open. 7 indicates abattery or other source of current also "included incircuit 5. t i o i It 'If-the mat section' l l is made of rubber will be sufficient toform a, simple, operative embodiment of my invention, but preferably the elasticresistan'ce of the walls of the recesses 2, 2, to deformation is reenforced by the use of a wave-like spring strip 8, of steel or similar elastic material, the'crests of the 2, 2. When such spring ings 9', 9, cut in the strips 8, 8, and to cause a portion 'ofthe body of the mat section 11 to protrude through each'of these "openings or slots 9, 9, thereby forming mat projections 10, 10, interlocking therewith," and to set the composition the foregoing described elements contact elements in this portion of the mat, an

as shown 'inthe drawing. This ensures the :insulation of the contact elements from the n spring strips in a very simple and efiective and economical manner if the mat is made of rubber or other insulating material, although a more eiiicient body of electrically insulating material, could be used for the purpose at these points, if found desirable. Also, for purposes of concealment and protection of the contact elements, I prefer to fasten a sea1- ing sheet 12to thatface of the mat section 11 in which the recesses are formed, and if the mat is made of a rubber composition this sealing sheet may readily be vulcanized to it so as to form a water-tight and air-tight protection for the contact elements.

In practice the recesses and the contained groups of contact elements in this'form of the invention would usually be arranged a series of parallel lines, as indicated in Fig. 2, and by staggering the groups in alternate rows with those in the other rows a very even distribution of contact groups throughout the mat is secured as there shown. All of these groups would be connected in series with the alarm 6 and the source of current 7 so that the moment pressure is applied to the mat above any of these recesses, and the deformation of the upper mat wall and of the recess beneath, indicated in Fig. 3, is produced, such deformation will separate the heads el, a, ofv the contact element onefrom another (orat least separate one pair) and thereby open the circuit and give the alarm.

In the modification shown in Fig. 5 an;

other form of circuit breaker is illustrated in which the recesses in the upper mat section 1 1 are located in longitudinally arranged pairs, one of each of which, as shown at 22,

may be larger than the other member 23 of the pair. In this arrangement the spring metal strip may have its undulations similarly proportioned and also formonetermi nalof, the circuitbreaker, the other terminal having the form of a stationary contact 'mem; ber 19 placed in recess 23. The wave-like spring strip has pairs of similarly unequal undulations 28 and 18, the contact 19 being located below and normally touching the under side of the crest of the smaller strip undulation 18. The lower strip 14 is made of some rigid insulating material, such as bakelite or vulcanite and the spring strip isrigidly fastened to it by rivets 15, 15, at the ends of each pair of undulations, but the spring strip is only loosely held to Mat each point between a larger andsmaller undulation by a sliding connection such as would be afi'orded by pin 20 passing through a slot 21. Preferably the crest and one side portion of each larger undulation is reenforced, as by a spring section 17 welded thereto, or by otherwise making this portion thicker than the rest. Also preferably, a space 24 is left in recess 25 in matsection 11 above the smaller undulation 18, so that the undulation 18,n1ay

freely bulge upward.

In operat on pressure on the upper. surface of the mat over recess 22 will straighten out more or less the longer undulation 28 of the spring strip and shove its left hand support point to the left, which action is made possible by the pin and slot connection 21, 21. This will cause the smaller undulation portion 18 of the spring strip to lengthen and bulge upward, thus breaking the circuit by separating it from contact 19. The reinforcement 17 prevents the right hand portion of undulation 28 from buckling under any such pressure, instead of swinging downward, without other deformation than a possible slight fiattening action, and so bodily shifting the left hand portion of strip forming that unduation to the left, as desired and above described.

In usesucha mat could be placed on one or more of the fire escape platforms 13 ofv a building, as shown in Fig. 4, \viththe alarm mechanism 6, 6, inside the building, or in a police station house, or watchmens ofiicc, with the result that when a second story man tries to sneak ill) the fire escape to find a window which can be forced, he would almost inevitably step on one of the mats and sound the alarm. In the same way, one or more small mats could. be set in the interior facing of a motor car body at points where they couldbe reached by the knee or elbow of an occupant who was under surw'eillancc by a gunman, and the same thing could be done in hotel elevators so that the operator could unobtrusively lean against the mat when he desired to send in an alarm without taking his hands down from over his head. Similarly one or more such mats could be concealed under a desk in an oilice, to serve as an alarm or as call apparatus for operation whenever the deslruser wishes to have his mail brought in as a hint to a lingering caller whom he desires to get rid of without appearingto be rude.

Other constructions of mat and other arangcments of separable contact members could be employed without departing from the underlying principle ofthe invcn ti on, as hereinbefore described and explained, so long as the same functions were retained wholly or substantially toproduce substantially the same results.

Having described my inventi on, I claim 1. As anew article of manufacture, an clcc; trical circuit breaker composed of a mat of, fiexiblematerialhaving a eavityiu its interior, with a pair of electrical contacts located in said cavity in such relation that while normally closed one on the other they may be separated, and contact opened, by movement of. onewall ofsuch cavity tending to collapse it. i

2. An article such as defined in claim 1 in which a plurality of cavities are proyided arranged in pairs and in which the contact m n s c mp e we r eef h sh is xe in the bottom of one cavity of each such paid while the other is'in the form of a wave-like spring strip substantially conforming in outline to the upper walls of the cavities and fixed at the outer ends of the pair of cavities, but having a sliding bearing at the juncture l thereof, whereby a depression of that undulation of said spring located: inthe cavity not fixed at the outer ends of the pairs of cavities, but having a sliding hearing at the juncture 7 thereof, the cavitycontaining said fixed con provided with a fixed contact produces a separation of it from the fixed contact member located in the other cavity. 7 I

3. An article such as defined in claim 1 in which a plurality of cavities are provided arsaid strip is reenforced to prevent local buckling action when it is pressed downward for the purpose set forth.

Signed at New York city, in the county of New York and State of New York this 25th day of March, A. D. 1932. a I


ranged in pairs and in which the contact elements comprise a pair one of which isfixed in the bottom of one cavity of each such pair while the other is in the form of a wave-like spring strip substantially conforming in out line to the upper (walls of the cavitiesand fixed at the outer ends or" the pair of cavities, Y

but having a sliding bearing at the juncture thereof, the cavity containing said fixed'contact member being of lesser dimensions than the other, whereby a depression of that un-.

spring stripsubstantially conforming in o'utline to the upper walls of the cavities and tact member being of lesser dimensions than the other, but having a free space above the spring undulation locatedthcrein to permit.

a free, upward, bulging movement thereof,

whereby a depression ofthat undulation of said spring located in the ca-vity not provided with a fixed contact produces a separation of it from the fixed contact member located in I the other cavity. 1

5. base of insulating material from which a fixed contact member projects upwardly and serves as one circuit terminal, combined'with In an electrical circuit breaker, a rigid a wave-like spring stripserving as the other circuit terminal and being fastened to said 7 base atvthe outer extremitles of each pair of undulations, while having a sliding bearing on said base at the j unctures' of each such pair of undulations, the under surface of one strip undulation normally resting on said fixed contact; whereby when the other undulation of said spring strip is'depressed, the first I I mentioned one, will bulge upward and separate it from said fixed contact member.

' 6. Acombinationsuch as defined in claim 5 in which saidsecond undulation portion of

Referenced by
Citing PatentFiling datePublication dateApplicantTitle
US2683784 *Apr 12, 1952Jul 13, 1954Rector William ABurglar alarm mat
US4188622 *Jan 27, 1978Feb 12, 1980Miller Larence GGarbage can alarm
US4390028 *Mar 25, 1981Jun 28, 1983Kabushiki Kaisha Morita SeisakushoOcclusion pressure sensor
US4554424 *May 25, 1984Nov 19, 1985Minnesota Mining And Manufacturing Co.Electrical switch
US5512716 *Nov 26, 1993Apr 30, 1996Mayser Gmbh & Co.Switching pad or plate
U.S. Classification200/86.00R, 340/666, 340/574
International ClassificationH01B7/10
Cooperative ClassificationH01B7/10
European ClassificationH01B7/10