US2857971A - Fire extinguisher - Google Patents

Description

Oct. 28, 1958 E. A. FERRIS 2,857,971

FIRE EXTINGUISHER Filed May 16. 1955 5 Sheets-Sheet 1 IN V EN TOR. EDMUND A HERR 1s md m,

14 TTORNE Kr Oct. 28, 1958 E. A. FERRIS 2,857,971

FIRE EXTINGUISHER Filed May 16. 1955 v 5 Sheets-Sheet 2 I N V EN TOR. foMu/va AFERR/s ATTORNE Y6 1958 E. A. FERRIS FIRE EXTINGUISHER 3 Sheets-Sheet 3 Filed May 16. 1955 INVENTOR. foMu/vo A. FERR/s BY 0 wmw A 7' TORNE YJ Unite Stats FIRE EXTINGUEHER Edmund A. Ferris, Eau Claire,

Products Co., Inc., Minnesota Win, assignor to Ferris St. Paul, Minn., a corporation of This invention relates to devices for extinguishing fires. More particularly this invention relates to new and improved fire extinguishing devices adapted to contain a heavy volatile liquid fire extinguishing agent and to release that agent when subjected to temperatures in a predetermined range.

It has been known to provide fire extinguishers adapted to contain a heavy volatile fire extinguishing liquid which will be released when some specific point or points on the container reach a predetermined temperature range. The liquid has been released by providing the container with fusible sealing plugs which will melt at specified temperatures to release the liquid or by triggering valve mechanisms which are sealed by a fusible material which will melt and permit the triggering mechanism to operate at the desired elevated temperature. Such prior devices have had the disadvantage that the elevated temperature caused by an unfriendly fire had to be felt at the specific localized points of control where the fusible seals were located in order to actuate the extinguishers.

Other fire extinguishers are known which are constructed of frangible material in whole or in part and are designed either to be thrown into a fire, breaking upon contact with a hard solid object, or to be burst by increased internal pressure created by expansion of a fire extinguishing liquid within the container. Extinguishers which must be thrown into or directed against a fire have the obvious disadvantage of requiring foreknowledge of the fire and are, of course, useless in combating fires which occur when the premises are left unattended or in secluded areas not normally under observation. Those extinguishers which depend upon internal pressure to rupture the container wall to release the fire extinguishing liquid are uncertain in operation due to the difficulty in constructing a container adapted to break at a predetermined pressure at a low enough temperature to effectively extinguish a fire before it has made considerable headway.

It is the principal object of this invention to provide a fire extinguishing device adapted to overcome these deficiencies of prior art devices. In its simplest form the fire extinguishing device of this invention comprises a liquid fire extinguishing agent contained in a thin flexible envelope which is rupturable by heat and/or pressure at a predetermined temperature range to release the fire extinguishing agent, the envelope in turn being encased in a substantially rigid protective outer shell of low melting point material or foraminous higher melting point material permitting rapid exposure of the inner envelopes to the effects of higher temperatures due to fire. In a modified form the device of this invention is comprised of a rigid tube impermeable to the liquid fire extinguishing agent closed with at least one fusible sealing member.

The invention is illustrated by the drawings wherein the same numerals are used to designate corresponding parts and in which:

Figure 1 is a front elevation of one form of the invention;

Figure 2 is a vertical section taken generally along the atent line 2-2 of Figure 1 and in the direction of the arrows;

Figure 3 is a front elevation of the envelope of fire extinguishing agent employed in this invention;

Figure 4 is a perspective view, partly broken away to show the interior, of one form of the invention especially adapted for use in file storage cabinets;

Figure 5 front elevation, partly in section, of another form the invention especially adapted for use in fuel storage tanks;

Figure 6 is a front elevation of another form of the invention adapted for hanging on inflammable Christmas trees, shown with one half of the shell removed to show the interior;

Figure 7 is a vertical section through a device as shown in Figure 6;

Figure 8 is a front elevation of an envelope of fire extinguishing agent as used in the form of the invention illustrated in Figures 6 and 7;

Figure 9 is a perspective View of still another form of the invention especially adapted for use on brooders and the like, with the end closures removed to reveal the interior of the device;

Figure 10 is a vertical section through a device as shown in Figure 9;

Figure 11 is a perspective view of a chick brooder showing one of the devices in use;

Figure 12 is a vertical section of a still further form of the device of the invention; and

Figure 13 is a front elevation, partly in section of another modified form of the fire extinguishing device of this invention;

Figure 14 is a front elevation of one form of holder for containing a fire extinguishing device;

Figure 15 is a vertical section taken on the line l5-15 and in the direction of the arrows of Figure 14;

Figure 16 is a perspective view of another form of the invention as especially adapted for use in filing cabinets; and

Figure 17 is an enlarged detailed sectional view of the fiuid release means of the device of Figure 16.

Referring now to the drawings and particularly to Figures l, 2 and 3, there is here shown one form of the invention designed for general purpose industrial, farm and home use. This device comprises a generally cylindrical outer shell it? molded in two opposed half sections 11 and 12 each with a peripheral outwardly extending flange 14. The flange is preferably enlarged at the upper domed end of the cylinder to form a hanging member 15. A hole 16 is provided in this member to facilitate hanging. The opposed sections 11 and 12 are adapted to be secured together along the opposite flange faces by means of heat sealing, adhesive, clips or the like.

The outer shell lid is preferably substantially rigidly formed of a synthetic resinous material capable of melting at the thicknesses employed in the temperature range between about to F. in order to expose the inner envelope of liquid fire extinguisher to the effects of the heat from the fire Within that range as will be explained hereinafter. One preferred material found to be admirably suited for this purpose is polystyrene. Other resinous and plastic compounds having properties making them capable of being formulated into molding material with the requisite softening points include cellulose acetate, cellulose acetooutyrate, cellulose nitrate, polyvinyl acetates, vinyl chloride-vinyl acetate copolymers and the like. Since some of these materials are themselves highiy inflammable it may be desirable to incorporate a fire proofing compound in the molding mixture.

The form of the invention illustrated in Figures 1 and 2 is intended to be suspended or hung at intervals over the area to be protected. To forestall the possibility that the whole outer rigid container may melt with such a rapidity that the hanging hole 16 will melt through and drop the device before the fire extinguishing agent has been released, the joined flanges 14 of the half sections are additionally held together by a metal foil pressure sensitive adhesive tape 17 binding the flange edges. The presence of this metallic tape is sufficient to support the receptacle during those few seconds required 'to release the liquid agent.

Held within shell is an envelope or bag 18 containing a liquid fire extinguishing agent 19. In its preferred form envelope 18 is made from a tube of thin flexible resinous sheet material which is insoluble in the liquid fire extinguisher, impermeable to its vapors, capable of being heat sealed as at ends 2t and rupturable by heat and/or internal pressure of the extinguishing liquid at elevated temperatures.

One preferred fire extinguishing liquid for use according to this invention is chlorobromomethane, a clear, colorless, heavy volatile, non-inflammable liquid having a sweet odor. Chlorobromoethane is a preferred material because it is liquid over a wide range of temperature conditions from its freezing point of l26 F. to its relatively low boiling point of 154 F. permitting its use in all climatic conditions normally encountered. When chlorobromomethane is used as the fire extinguishing agent the preferred envelope material is polytrifluromonochloroethylene, an inert, tough, non-porous heat sealable material available as thin flexible sheet material and tubes and having wide temperature resistance being flexible from about 85 F. to 375 F. Polytrifluoromonochloroethylene is available in sheet and tube form under the trade mark designation Trithene from the Visking Corporation. It is readily heat scalable at from about 550 to 600 F. at about pounds pressure.

In general the fire extinguishing agent should be liquid at ordinary temperatures; it should have a low boiling point below about 180 F; its vapors should be heavier than air so as to extinguish by a blanketing action and, of course, should be non-inflammable. Although chlorobromomethane is a preferred agent, other liquids such as carbontetrachloride and trichlorotrifluoroethane having 7 the requisite properties and may be used. Although carbon tetrachloride freezes at -9 F. that freezing point may be lowered by use of a suitable depressantl Other suitable materials for forming the envelope include polyethylene, nylon, rubber hydrochloride, butadieneacrylonitrile copolymers and like sheet and tubular material. The envelope is preferably filled to about 80% of its volume capacity and this filled envelope should in turn occupy about 80% of the capacity of the outer shell.

In use the fire extinguishing device is hung at spaced intervals in the area desired to be protected from fire. In theevent of a fire, as the elevated temperatures caused by the flamesreach any of the fire extinguishing units the Walls of the outer shell soften and collapse exposing the envelope walls to the effect of the added heat. By this time, at the softening temperature of the shell, the low boiling point liquid extinguishing agent in the envelope will be boiling vigorously. The elevated temperatures occasioned by the fire cause the softening and weakening of the envelope walls. This, alone or in company with the internal pressure exerted by the boiling liquid within the envelope, is sufficient to cause the envelope to rupture, releasing the extinguishing agent. The fire extinguishing agent at this point will be largely in the vapor state or will instantly vaporize. The heavier than air vapors will then flow downwardly smothering the fire with a blanketing action. The most effective agents are those, like chlorobromomethane, which extinguish by a blanketing action rather than by quenching and cooling. This type of fire extinguishing agent is particularly effective against flammable liquid and electrical fires. The provision of metal tape around the flanged edges'of'the outer shell insure against the shell softening and'dropping before release of the fire extinguishing liquid. Contrary to earlier the extinguishers, the device in this invention is effective if the predetermined elevated temperatures are detected at any point on the surface of the outer shell, rather than at a specific localized point of control.

There is shown in Figure 4 a specialized form of the device of this invention especially adapted for use in file storage cabinets. This form of the device includes a flat rectangular outer shell 21 made up of molded section halves in much the same manner as previously described for the of the invention illustrated in Figures 1 and 2. The outer shell contains a flat envelope 22 of liquid fire extinguisher. The outer shell 21 is of a size and shape corresponding to file folders and this unit in use is inserted preferably in the top drawer of a file cabinet. under the influence of elevated temperature exposing the inner shell which in turn'ruptures releasing the'fire extinguishing agent in the manner heretofore described, the vapors descending through the cabinet and extinguishing the fire in whatever drawer it occurs.

A further form of the invention adapted for use in fuel storage tanks is shown in Figure 5. This form of the invention comprises an elongated spherical outer shell 24 made up of two opposed sections 25 and 26. Lower section 26 has slightly enlarged open face providing a rim 2'2 for receiving and positioning the opposed open face of upper section 25 for forming a sealed unit. Con tained within this unit is a sealed envelope 28 of fire extinguishing liquid. The sealed unit 24 is adapted to float upon the surface 29 of a liquid fuel tank, for example, the gasoline tanks of aircraft. in'the event of fire in the fuel tank the confined heat within the tank quickly causes the outer shell and envelope to rupture re leasing the fire extinguishing liquid and smothering the fire before an explosion can occur.

A decorative and ornamental form of the invention is illustrated in Figures 6, 7 and 8. In theparticular embodiment illustrated the fire extinguishing unit is'formed in the shape of a bell especially adapted for use as 'a safety ornament on a Christmas tree. Obviously myriads of other shapes for other specific purposes may be devised and are within the purview of this invention. The bell unit 30 is made up of two flanged bell halves 31- and 32 sealed together at the flange faces to form the unit and enclosing an envelope 34 of fire extinguishing liquid;

Each holiday season hundreds of tragic fires occur as a result of Christmas trees becoming ignited and burning. Because in a tree the fire rises rapidly, burning as it goes, blanketing the burning area below with a fire extinguishing agent is sometimes insufficient to extinguish the blaze. Accordingly, for maximum protection a plurality of these fire extinguishing units should be used in a Christmas tree spaced vertically at intervals up to about 2 feet. The operation of this form of the'iriv'ention is likewise similar to that described in connection with Figures 1 and 2.

A somewhat different form of the inventiori iss'hown'in Figures 9, 10 and 11. The device here illustrated is especially designed and adapted for" use'on a brood'e'r'although it is equally adapted to other uses; Tris-breeder unit 35 comprises a tube 36, preferably fermed of' sheet metal, having a spring clip member 37 extending along one side and having a plurality or errorations' 38 around the lower periphery of the tube and extending for its full length. An elongated envelope 39 of liquid fire extinguishing agent is contained within the tube which is then closed with any suitable closures'suchas plugs 40. As shown in Figures 10 and 11 the fire extinguishing unit clips onto the edge of the overhanging wall42 of brooder 41. The clip'rnember may be narrower as at 37A of Figure 11 to facilitate clipping the unit to the overhanging wall ofa'cir'cular brooderl The rigidouter shell of this unitprotects the inner In the event of fire the outer shell ruptures envelope from rupture, as by pecking of chickens, but at the same time permits free escape of the fire extinguishing fluid through perioration'; 38 when the fluid is released from the envelope. When tube 36 is formed of metal as in the preferred embodiment the metal assists in rapidly conducting the heat caused by a fire to the inner envelope to facilitate the early release of the fire extinguishing liquid. The metal shell can conveniently be roll formed from strip material with the clip integral with the tube and spot welded at the juncture between the clip members and the tube wall.

A further form of the extinguisher of this invention is shown at Figure 12. In this form the device comprises an elongated tube 44 closed at one end and having a hanging member 45 at that end with a hole 46 for hanging. The opposite end of the tube is open and flared slightly to form a seating rim d? to receive a closure. Tube 44 is preferably formed by injection molding of aluminum. T he closure for the open end of the tube is comprised of a press stamped metal plug having a diameter substantially less than that of the open end of the tube. Positioned over the inner end of plug 48 is a relatively thick layer 49 of a relatively low melting point plastic or resinous material having properties such as are required for the rigid outer shell in the form of the invention shown in Figures 1 and 2. This layer 49 may be applied as a coating or may simply be applied as a sheet before plug 48 is pressed into rim 47. Superimposed upon layer 49 is a thinner layer 561 of a material which is impervious to the eifects of the fire extinguishing liquid 51. Where chlorobromomethane is the fire extinguishing liquid layer 5% is preferably polytrifluoromonochloroethylene applied as a sheet and held taut by being pressed into rim 47 with plug 48. Plug 48 with layers 49 and S6 is of a dimension to fit tightly in rim 47 when pressed into the open end of the tube. Thereafter the edge 52 of the rim is preferably turned in slightly to retain the plug but the extent of this turning in is less than the combined thickness of the two plastic layers. That is, plug 48 must still be capable of freely passing through the crimped end of tube 44.

In use this device is suspended in the area desired to be protected from the ravages of fire. if a fire occurs and the temperature rises to the predetermined range indicated by the selection of the material of layer 4% this layer melts releasing the plug and the fire extinguishing liquid. The metal of the plug assists in conducting the heat to the plastic layer 49. Even though only one side of the unit is subject to the elevated temperature the cfiects of that temperature are rapidly distributed around the periphery of the plug to soften the layer 4-9. At the same time plastic layer 56 assists in this softening by insulating layer 49 from the cooler body of liquid on the inside of the tube. As the temperature rises the lowboiling point liquid fire extinguishing agent begins to boil increasing the internal pressure and assisting expulsion of plug 48.

Alternatively metal plug 48 and resinous layer 419 can be replaced by a wholly fusible plug such as Woods metal or Rose metal, Lipowitz alloy or polystyrene or the like, but retaining resinous layer 49 to seal the tube and serve to insulate the plug from the cooler liquid.

A still further form of the invention is shown in Figure 13 wherein the fire extinguishing device comprises a metal cylindrical tube 55, open at one end and having a hanging member 'e'd at the other. Tube 55 is preferably drawn from brass. The open end of the tube is slightly larger than the tube body to provide a shoulder 57 upon which the releasable fusible plug closure seats. The closure comprises a narrow plastic or resinous washer or ring 58, impervious to the effects of the fire extinguishing liquid and fitting snugly within the tube against shoulder 57.

Resting against washer 58 and fitted loosely within the tube is a plastic disk 59 which has a thinned or weakened portion 60 in its center. Washer 58 and disk 59 are preferably formed of polyethylene. Overlying plastic disk 59 is a metal disk 61, also fitted loosely within tube 55. Disks 59 and 61 are of dimensions such that theyare too small to be retained with a sliding fit within the tube. Metal disk 61, and, accordingly, washer 58 and disk 59, are held soldered in place by a ring 62 of Woods metal or similar low melting point material melted around the periphery of disk 61. Disk 59 is forced tightly against washer 58 by metal disk 61 to provide an effective seal of resistant resinous material in contact with the extinguishing liquid.

Metal disk 61 is provided with a small opening 64 which is in registry with thin or weakened spot 60 in plastic disk 59. In assembling the fire extinguisher, washer is first inserted to rest against shoulder 57. Plastic disk 59 is dropped into place against washer 58 and metal disk 61 is inserted against the plastic disk and soldered to the tube 55 around its periphery with. a low melting point metal. The fire extinguishing fluid 65 is then injected under pressure through a hollow needle inserted through hole 64 and through the thin spot 60 in the plastic disk. The tube is filled to from about 75 to of its capacity with the liquid extinguishing agent. When the needle is withdrawn, the rupture in the thin spot of the plastic disk is virtually self-healing due to the inherent resiliency in the plastic material. Hole 64 is then sealed with a spot 66 of low melting point metal.

While a minute amount of liquid may remain between the plastic and metal disks, this volatilizes rapidly in the event of a sudden rise in temperature due to a fire and assists in expelling the metal disk. The extinguishing device is suspended from its hook 56 over areas desired to be protected from fire. In the event of fire in the vicinity of the extinguisher a rise in temperature causes softening and melting of the solder ring 62 sealing the end closure of tube 55. Woods metal, for example, melts at 158 F. At this temperature chlorobromomethane boils. The pressure exerted by the expanding fire extinguishing fluid readily expels the loosely fitted plastic and metal disks and the softened metal seal and allows the fire extinguishing fluid, at this time in the vapor state, to flow down as a smothering blanket over the fire.

One form of inconspicuous hanger means for containing the fire extinguishing device of Figures 12 and 13 is shown in Figures 14 and 15. The hanger comprises a background plaque or base 67 upon which there is displayed a three-dimensional representation or shell 68 of some product being advertised. This representation is hollow, being generally molded from some rigid synthetic resinous material, and fastened by means of suitable bolts 69 or other means to the plaque, which usually also bears some advertising indicia. Plaque 67 is attached to a wall 70 or other support. The representation of the advertised product is open at the bottom and the extinguishing device is suspended from the fastening means 69, preferably extending just slightly below the bottom of the display representation so as to leave the tube closure unshielded in the event of fire.

The display device is hung in grocery stores, drug stores, soda fountains, bars and the like, performing their intended purpose of calling the attention of the public to the merchandise advertised and at the same time acting as an unobtrusive silent sentinel constantly on guard against fire.

A modified form of file storage cabinet extinguishing device is shown in Figures 16 and 17. This form of the fire extinguisher comprises a generally fiat, thin and rectangular metal case 71, preferably formed from brass, and of a size and shape adapted to fit in the drawers of a file cabinet along with the filed material. A closure tube 72 is welded or soldered internally in the opposite lower side edges of the case '71. Tube 72 is crimped around its periphery to form a shoulder 74. In all other respects the closure corresponds to that previously de- 7 scribed with res ect to the "device of Figure 13. The erasure includes aplastic ring 5821' resting against shoulder 74, ensue disk 5 92: having a thin spot 6011; metal disk 61 havin its eentml opening 64:: in registry with thin seer 61m, and the where being sealed and held in place seiner-ring 52d arid solder spo't 66a.

The tire eitinguishih'g fluid 75 is injected through the closure after is installed in the same manner heretofore described. The metal and plastic disks fit loosely in tube 7-2 '50 as to be readily expell d in the event of fire. The unit fuilctions in the event of fire in the manner of other forms of the invention. The closing means releases the extinguishing agent which vapo'r-izes, but being heavier than airdescends and spreads but as a smotherin blanket which e'fiec'tively puts out the-fire.

As many apparently widely different embodiments of this invention may be made without departing from the spiritand scope thereof, it is to be understood that 1 do an limit m self is the specific e'r'nbbdir'nents herein.

' What I claim is:

1. A fire extinguishing device comprising an elongated tub erased at both ends and containing a low boiling point liquid fire extinguishing agent, one of said ends Being closed with a fusible plug, and an insulating barriei layer or a thin synthetic resinousfilm insoluble in said liquid agent and impermeable to the vapors of said agent imposed between said plug and said liquid agent.

2. A fire eiitinguishi'rig device comprising a rigid case containing a low boiling point liquid fire extinguishing agent; part of said case comprising a rigid tube containing a releasable fusible plug closure; a shoulder in said ruse against which said closure rests said closure includ Trig an annular ring of synthetic resinous material insoluble in said liqiiid agent inserted with a sliding fit agains said shoulder, a disk :fieXible" synthetic resinous ifieiteritl insoluble in said liquid age t and having di mensions too manta be retained with a sliding fit in said tiilie held against said ring, a relatively rigid disk having dimensions ea small to be retained with a sliding fit" in" said tube held against said flexible disk and sealed in said tube with a low melting point fusible material, an injection hole in said relatively rigid diskadapted to receive a thin tubular filling element for injecting fluid under pressure through said fleXible disk and into said base, and a spot of fusible material sealing said hole.

3. A fire extinguishing device according to claim 2 further characterized in that said case and relatively rigid disk are of metal and the low melting point sealing material is a fusible alloy.

4. A fire extinguishing device according to claim 2 further characterized in that said annular ring and flexibie disicare of polyethylene.

5. A fire extinguishing device according to claim 2 further characterized in that said liquid fire extinguishing agent is chlo'robrom'omethane.

6. A fire extinguishing device accordingto claim 2 further characterized in that said case is generally tubular in shape and said rigid tube containing the closure means is an extension thereof. p

7. A fire extinguishing device according to claim 6 further characterized in that said tubular case is contained within the hollow of a three-dimensional representation of a proprietary product, said representation being open at the bottom and supported upon a base adapted to bear advertising indicia, the tubular case being suspended with the releasable closure presented in the open bottom of the product representation.

References Cited in the file of this patent UNITED STATES PATENTS 1,208,549 Haller Dec. 12, 1916 1,348,565 Jenkins Aug. 3 1920 1,3 9,179 Lee Feb. 22, 1921. 1,458,972 Brande June 19, 1923 2,011,327 Stover et al. Aug. 13, 1935 2,214,307 Mountford Sept. 10, 1940 2,273,515 Dachlauer Feb. 17, 1942 2,293,366 Solosko Aug. 18, 1942 2,560,468 Morton July 10, 1951 2,612,224 Zabriskie Sept. 30, 1952

Claims (1)

1. A FIRE EXTINGUSHING DEVICE COMPRISING AN ELONGATED TUBE CLOSED AT BOTH ENDS AND CONTAINING A LOW BOILING POINT LIQUID FIRE EXTINGUISHING AGENT, ONE OF SAID ENDS BEING CLOSED WITH A FUSIBLE PLUG, AND AN INSULATING BARRIER LAYER OF A THIN SYNTHETIC RESINOUS FILM INSOLUBLE IN SAID LIQUID AGENT AND IMPERMEABLE TO THE VAPORS OF SAID AGENT IMPOSED BETWEEN SAID PLUG AND SIA D LIQUID AGENT.

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