US2368340A - Fire extinguisher - Google Patents

Description

Jan. 30, 1945# "'J. W. WRIGHT -FIRE EXTINGUISHER 'Filed Deo. 18, 1941 l Patented Jan. 30, 1945 Fyr-Fyter Company,

ration of Ohio Dayton, vOhio, .a corpo- Application December 18, 1941, Serial No. 423,510 i 5 Claims. v(C1. 299-96) This invention `relates to re extinguishers and more particularly to lire extinguishers adapted for use in extremely low temperatures.

Certain types of commercially available fire extinguishers are specially constructed for low1 temperature operation but 'even with su'ch extinguishers, it is found that their operation either becomes unsatisfactory and unreliable or ceases entirely when the temperature to which they are exposed drops to the range about 45 C. (--49o I F.) and below. At temperatures of this order, extinguishers of the vaporizing-liquidtype may become inoperative due to freezingof the solution if such devices are lled with the ordinary carbon tetrachloride base fluid or due to the promptly and easily actuated to closed or open position. l

Another object of this inventionvis to providean extinguisher fluid suitable for use in an extinguisher capable of efficient operation throughout a Wide temperature range from high summer temperature to extremely low temperatures which Y fluid will not freeze when exposed to extremely freezing 'of moisture condensed from the air on the operating mechanism. Extinguishers ofthe acid-reaction type are ineffective at these temperatures due to the feeble chemical reaction `which occurs in such devices at low temperatures.

In the case of extinguishers of the compressed 'gas operated type, if the extinguisher is operated by compressed carbon dioxide gas the vapor pressure of this material at 45 C. is so low Vthat insufcient pressure can be obtained Within the extinguisher to cause an effective discharge 'of the'contents. Where other compressed gases,

such as nitrogen, are used in sucient quantity to cause an effective discharge at this low temperature, an abnormally high pressure will begenerated within the container when the device lis operated at room temperature at high summer temperatures, a pressure which may be suicient vto cause danger of rupture of the extinguisher container. l

It is therefore one of the principal objects 'of this invention to provide a re extinguisher which is adapted to operate reliably and effectively over a wide range of temperatures. from an extremely low temperature up to the temperatures encountered in hot summer conditions.

Another object of the invention is to provide -a re extinguisher in which the operating mechanism is protected against condensation or colflection of moisture thereon so that the extinguisher remains at all times in condition to operate efficiently over a Wide range of temperatures. A further object of this invention is to provide a re extinguisher having a shut-off valve of lsuch construction that it will be and remain operable at the lowest temperatures atwhich the extinguisher may be used, in which condensation -ofmoisture even if present will not interfere with 'the operation, and which at all times may be low temperatures for long periods of time.

Still another object of this invention'is to provide an extinguisher simple in construction, having relatively few moving parts, and of sufficiently rugged construction that it may be used under extremely adverse conditions.

In the drawing which disclosesa preferred embodiment of the invention,

Fig. 1 is an elevational View of an extinguisher constructed in accordance with this invention;y

Fig. 2 is a vertical sectional view of thef extinguisher on a larger'scale taken through the axis of the outlet valve, certain parts being broken away to more clearly show the construction; and f Fig. 3l is a partial sectional view through the outlet valve actuating lever on a still larger scale.'

As shown, the extinguisher consists of a cylindrical container I0 having rthe bottom cover II with a suitable yfoot-rest I2 'and a top cover I3, the two end pieces being suitably fastened to the cylindrical side wall by soldering, Welding, or other suitable means. Attached to the cover I3 is a fitting I5, held in place thereon by bolts or the like and sealed by means of gasket I6.- Pump cylinder I'l is threadedly carried by such fitting as shown at I8, supporting the pump cylinder generally vertically within the cylindrical casing I0.` Preferably a liquid pump is provided, having a tubular piston rod I9 closed at its upper end where it is secured to the operating handle 20. The piston rod extends through the fitting and into the interior of the casing I0 where it is provided with a pump plunger 2I, which is centrally -apertured as shown at 22 to provide a passage leading to the check-valve 23. The lower end of the piston rod carries the valve seat member 24 in which the apertures 25 are formed to provide a path for the now of the liquid in the 2 y e possibility of picking up slush, foreign matter, or the like during operation. The total area of the perforations in member 28 is preferably in excess of the area of the passages through the two check-valves so that a free inward flow of fluid is provided for at all times.

In the operation of the pump, as will be clearly understood, upon reciprocation of the pump handle 28, fluid is delivered under pressure during each upward and downward stroke, into the annular space 26 from which it is delivered into the globular area 30 formed in fitting l5. Some air f becomes trapped in the upper portion of this space and in the hollow piston rod above the valve seat member 24 and thereby serves as a cushioning medium to provide for moreeven now in the o-utward discharge of the fire extinguishing iiuid.

Because it is necessary to adequately protect the pump during operation against accessof moisture thereto, which at the very low temperatures for which the pump is `adapted. might resultin making it impossible to properly operate the pump, means are provided for assuring that should any moisture collect by condensation or otherwise, it will not be in such location that it can impair the proper operation of the extinguisher. For this purpose a shoulder 35 is formedwithin the inner portion of iitting l against which there is seated a lowergland member 36. Suitable packing 31 is received between the lower gland and an upper gland 38. Spaced above the lower packing is an upper packing supported from gland 38 which has a seat to receive a cylindrical flange 4D formed on a gland member 4 l Upper packing material 42 is received between gland 4I and an outer gland nut 43 which is suitably threaded ontoan upwardly projecting neck portion of fitting l5. When nut 43 is tightened, it effects compression of both the outer packing 42 and inner packing 31, the shape of the gland surfaces being such that the packings are forced into close-sealing contact with the piston rod.l Outer packing 42 when placed in use is thoroughly saturated with a light mineral oil, such for example as kerosene or other suitable oil having a freezing point sufficiently below the l temperature to which the extinguisher may be subjected to assure that it will remain fluid at all times.

Flange 40 is located intermediate the wall of tting l5 and the piston rod and is provided with a series of apertures 45 which communicate with other apertures 46 formed in the interior wall of tting l 5, thereby providing a path communicating from the space around the piston rod and between the two packings, into the passage 48 formed in the tting l5 but located exteriorly of the discharge space 30 and hence not subject to discharge pressure. Ports 49 are'formed in the lower wall of the fitting l5 and the end cover i3 to provide for communication between this passage 48 and the interior of the casing IIJ.

" In operation, as" the piston is reciprocated, the flued is subjected to discharge pressure and iiows into the globular section 30. Such iiuid asv may leak along thepiston rod and through packing 31 will collect in the space between the packing 31 and the upper packing 42, and will be discharged back through apertures 40, 46, passage 48, and aperture 49 into the main body so that no fluid will be lost. The air necessary to replace thedischarged fluid will be drawn inwardly through the o'uter packing 42, the oil contained therein saturating the intersticesin the packing and preventing the deposit' of any material quantity of moisture in thepacking'as by condensation or otherwise which might result inmaking the packing hard and ineffective or in freezing the piston rod in place. If any small quantity of moisture is left in the packing, it is distributed and dispersed through the oil and even upon freezing does not render the packing stiff or impair its eiiectiveness. The path for the supply of the air into the casing is the same'as that described for the leakage liquid, theair further serving t0 facilitate the return of the liquid as it ows back into the casing.

A shut-ofi valve is provided for controlling the discharge of the fluid from the extinguisher, such shut-off valve being located within an extended portion of fitting l5. As shown, the fitting is formed to provide an upwardly extending valve seat\55,`the valve member 56 being adapted to close upon the seat to prevent discharge of the fluid. A spring 51 located below the valve 56 provides for normally urging the valve to raised or open position, permitting the.,discharge of the fluid from the globular portion 30 into the discharge chamber 58 formed above the valve.

Actuation of the valve is controlled from-an external manually operable lever 68, pivotally mounted on pin v6i carried in a threaded cap .por-

tion`62 adapted to be received within la seat formed above discharge chamber 58, Lever 6D carries a cam portion'63 which is adapted to en gage and effect downward movement of an operating pin 54 having a collar 65 thereon to limit its upward travel, and also forming a shoulder for engagement with resilient means 66. Such resilient means engages the valve at `its lower end, and upon the turning of hand lever 6U to the position' shown in Fig. 3, pin 64 is actuatedto its lowermost position in which pressure is `applied to the upper Yend of spring '66, to be transmitted therethrough tothe valve member, and to urge said valve member into a yieldably held closed position, overcoming the counter action of 'spring 51` "In orderA4 to assure that the valve parts will remain operative under all conditions of usev and in the extremely low temperature range desired, means are provided for lcompletely preventing communication between the valve actuating parts and the linterior of the casing, thereby prevent- 'ingpassage of moisture'intothe cylinder yand sealing the operating mechanism electively so that no collection of moisture can occur with resultant freezing of the valve parts.

For this purpose, a flexible bellows-like member orSylphon' 68 is provided, the upper end thereof being secured in sealed relation by soldering or'the like toa soft copper washer 69' held between the bottom of valve nut 62 and its seat in fitting t5. The lower end of member 68 is fastened, as by soldering, in sealed relation to a flanged seat on thel upper side of valve member 56. v The arrangement is such that whileithe upper end ofthe bellows-like member is heldin nxed relationship with the wall of the chamber, the lower'end can Imove with the valve,- .the-'whole ybellows lexpanding and contracting sas necessary to provide for-such movement while'maintaining thesealed relationship. When expanded 1. and with the valve closed, access of lmoisture from either the discharge outlet or from thespace surrounding the operating pin Skis-completely prevented, and any discharge or leakage `of fluid from inside the extinguisher is' also prevented. When, however, handle 68 rotated -to'its--upright position, the pressure is removed fromvpin 64, releasingspring- 66, and spring 51 thenieiects the raising of the valve-with corresponding co1.-

-lapsing movement of bellows 68. position the discharge path-is open, and the fluid isdisi charged under the pumping action past the 'valve seat, and into the discharge chamber 58, i In this construction-clearance is preferably provided-bevalve is greatly reduced and if present its .effect Wouldnot be objectionable or result the operation of the Valve.

An outlet tting 1B communicates with the disin impairing charge chamber 58, and to the fitting is attached -a flexible hose 'l2 provided with Va discharge nozzle 13.

, A suitable fluid is provided, which may be introduced into the `casing through a filling opening such as that shown at 15, in the form of a I threaded cap nut positioned in the top cover I3. It is highly important tovprovide a fiuid which will not develop excessive vapor pressure at even the high summer temperatures that maybe encountered, such as up to 50 C. (122i F.), and which will likewise not freeze or become so thick as to make it difficult to handle, at the very low temperature range desired, of the order of 45 C. and below. A suitable fluid for this purpose, and one which is found to remain substantially inert in the usual construction of extinguisher parts has been found to be one comprising a mixwith an aperture providing a passage for theinlflow of air. and the return' of any leakage fiuid, and a return passage into the interior of said casing formed in said fitting exteriorly of the discharge passage therethrough.

2. In a fire extinguisherof the character 'de'- scribed adapted for-operation at low temperatures, an extinguisher casing for receiving a quantity f ofi'ire extinguishing liquid, a liquid pump 'for subjecting said liquid to pressure,r a fitting extending from one end of said casing and fastened thereto providing for the mounting of said pump thereon, said pump havinga piston rod extending outwardly through said fitting, a plurality. of -packing means carried by said fitting and located in spaced relation with each other .along said ypiston rod-the outermostsaid packingl being saturated with a light non-freezing oily mal terial filling the interstices in said packing and ture or carbon tetrachloride and trichlorethylene.

A mixture of these materials may be formed comprising a major portion of the carbon tetrachloride and a minor proportion by volume of the trichlorethylene, and is found to be an efficient fire extinguishing medium with a freezing point cessfully operated at temperatures as low as 65"`v C., with entirely satisfactory results.

While the foregoing description has been directed to preferred embodiments of the invention, it is to be understood that the invention is not limited to the embodiments so described, and that changes may be made therein without departing from the scope-of the inventionwhich is defined in the appended claims.

What is claimed is: l

l. In a fire extinguisher of the character described adapted for operation at low temperatures, an extinguisher casing for receiving a quantity of re extinguishing liquid, a liquid pump for subjecting said liquid to pressure, a fitting extending from one end of said casing and fastened thereto providing for the mounting of said pump thereon, said pump having a, piston rod extending outwardly through said fitting, a plurality of packing means carried by said fitting and located in spaced relation with each other along said piston rod, the outermost said packing being saturated with a light-non-freezing oily material filling the interstices in said packing and preventing. thecollecting and lfreezing of substantial quantities of moisture therein, said vfitting being formed intermediate said packings preventing the collecting and freezing of substantial quantities of moisture therein, said fitting being formed'intermediate said packings with an ,aperture providing a passage for the in-flow of air and the return 'of any leakage fluid, a return passage into the interior of said casing formed in said fitting exteriorly of the discharge passage therethrough, said fitting being formed to provide an outlet for discharging the fluid from said casing, a shut-off valve in said outlet, means operable from outside said fitting and having a part extending thereinto for actuating said shut-off valve, and means for enclosing and sealing said actuating part to prevent communication between said part and the fluid being discharged.

3. In a fire extinguisher of the character devscribed adapted for operation at loWtemperatures, an extinguisher casing for receiving a quantity of fire extinguishing liquid, said casing having a return flow opening in the upper part thereof; a liquid pump for subjecting said liquid to pressure to discharge the same, a fitting extending from one end of said casing and fastened thereto providing for the mounting of said pump thereon, said pump having a piston rod extending outwardly through said fitting, means including an inner wall in said fitting forming a chamber above said pump for the discharge of the liquid under pressure, packing means surroundinsr said piston rod carriedby said fitting and located above said discharge chamber, said packing being saturated with a light non-freezing oily material filling the interstces therein and preventing the collecting and freezing of substantial quantities of moisture therein, and an outer wall on said fitting defining with said inner Wall thereof a return flow passage extending from above said packing to saidreturn flow opening to provide for the return flow into said casing of any liquid leaking past said packing.

4. Ina fire extinguisher of the character de scribedadapted for operation at low temperature having an extinguisher casing for receiving a quantity of fire extinguishing liquid and a pump for subjecting said liquid to pressure, the combination of an outlet fltting in communication with said casing for ldischarging the liquid therefrom, a shut-off valve in said outlet fitting, an operating pin extending into said fitting from the exterior thereof and into the path of the liquid discharge, saidv pin being mounted in said outlet fitting for longitudinal sliding movement, resilient means actuated upon said movement of said voperating 'pinfor effecting the closing of said .shut-off valve, sealing means for enclosing said resilient means and said operating pin prevent- 4- 4:mamme ing communication between .asa-id 'n.parts and .the liquid being discharged ,from fthe :,casing, r:and meansv accessiblefrom outside :said casing' and'cooperating with. said operating :pin providing :for longitudinal slidingf said pin :overasubstantial range `of travel with ycorresponding -move ment of said valve between its vopenand its closed positions,

5. Ina fne extinguisher of thevcharacter described adapted `for operationat .low .temperatm'eshaving aneextinguisher casing for receiving a quantity of j reextinguishing liquid .and ra. pump for subjectingsaid liquidato pressure, the combination of .an .outlet fitting forqdischarging the liquid from said Vcasing, arshut-off .vaivein said outlet fitting, a. .seat with which said valve cooperates `to 1 prevent Aliquid discharge. spring :erable for releasingsaid pinto provide for openofxsaid-valve, resilient means within said iittingn'thegpath of dischargeof said uid for transmitting the vmovement of said pinto said 10 naiven-toCIoSe-andseat the same v'against the action :of said spring means, land means forfeniclosingriand .sealing said operating pin :and-its 1associatedAresiiient means to preventcommunication between rsaid parts and said extinguishing 15 'lquih Y -JOHN- W. WRIGHT.

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