US3719232A - Fire extinguisher - Google Patents

Abstract

D R A W I N G
A REFILLABLE HAND FIRE EXTINGUISHER COMPRISED OF A BLOWMOLDED THERMOPLASTIC GLASS-FIBER REINFORCED PLASTIC, EXTINGUISHING-MATERIAL-CONTAINING BOTTLE, ON THE MALE BUTTRESSTHREADED NECK OF WICH A LEVEL-VALVED DISCHARGE NOZZLE AND HAND GRIP HEAT IS TREADED AND SEALED TO THE BOTTLE, WITH A RADIALLY PORTED IS THREADED AND SEALED TO THE BOTTLE, HEAD COAXIALLY SPACED FROM A DISCHARGE RISER TUBE MOUNTED IN THHE NECK AND EXTENDING TO THE BOTTLE BOTTOM; A REPLACEABLE ELONGATED PRESSURIZED CO2 GAS CARTRIDGE, COAXIALLY MOUNTED IN THE DISCHARGE TUBE BY ITS PIERCEABLE HEAD THREADED INTO THE BOTTOM END OF THE VALVE INLET NIPPLE; AND A RECIPROCABLE VALVING MEMBER CARRYING A CARTRIDGE PIERCING POINT. A VALVE SAFETYING WEDGE AND EXTINGUISHER STOWAGE FITTING, BOTH OF MOLDED PLASTIC, ARE ALSO SHOWN.

Description

March 6, 1973 G. GUBELA FIRE EXTINGUISHER 3 Sheets-Sheet 1 Filed March 15, 1.971

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March 6, 1973 s. GUBELA FIRE EXTINGUISHEB 3 Sheets-Sheet 3 Filed March 15, 1971 m T MW VU W G R E T N "U G b m 9 i| mm B F F K m w fyK Arr'y.

United States Patent 3,719,232 FIRE EXTINGUISHER Gunter Gubela, Poll-Vingster Strasse 150-160, Cologne, Kalk, Germany Filed Mar. 15, 1971, Ser. No. 124,261 Claims priority, application Germany, Mar. 14, 1970, P 20 12 142.0 Int. Cl. A62c 13/00 US. Cl. 169-31 P Claims ABSTRACT OF THE DISCLOSURE A refillable hand fire extinguisher comprised of a blowmolded thermoplastic glass-fiber reinforced plastic, extinguishing-material-containing bottle, on the male buttressthreaded neck of which a lever-valved discharge nozzle and hand grip head is threaded and sealed to the bottle, with a radially ported valve inlet nipple integral on the head coaxially spaced from a discharge riser tube mounted in the neck and extending to the bottle bottom; a replaceable elongated pressurized CO gas cartridge, coaxially mounted in the discharge tube by its pierceable head threaded into the bottom end of the valve inlet nipple; and a reciprocable valving member carrying a cartridge piercing point. A valve safetying wedge and extinguisher stowage fitting, both of molded plastic, are also shown.

Hitherto self-discharging fire extinguishers have generally comprised, as the container for the fire extinguishing substance, a metal pressure vessel, usually of steel, which is subject to the danger of corrosion, especially though not exclusively, by the contents. Such extinguishers consequently have required constant inspection and testing, and often after a few years have become unusable.

By the present invention, hereinafter disclosed in a specific embodiment of a hand fire extinguisher, especially suitable for use in various engine driven vehicles, such as automobiles, trucks, pleasure watercraft, aircraft, as well as other environments, there is provided an extinguisher structure comprised principally of synthetic plastic components which both overcome the aforementioned disadvantages of prior extinguishers and offer advantages in light weight, ease, and low cost of fabrication, as well as other desirable characteristics.

In brief, the main container for the extinguishing material is a preferably glass fiber reinforced thermoplastic bottle, for example, blown from a heated tube of say polyethylene stock material into an appropriate mold, thereby attaining some desired form with uniform and increased strength and rigidity. A valved nozzle and grip head assembly includes as its principal part an injection molded element of a thermoplastic material such as polyethylene, providing integrally a valve body screwed onto the bottle neck, a discharge nozzle connecting through valve passages with the bottle, a hand grip element, and a support for an internal pressurized gas cartridge.

Moreover, as hereinafter detailed, the bottom end of the discharge head body element has such a cross section and is so concavely shaped relative to a convex shape of a shoulder region below the bottle neck that, in conjunction With the resiliency of the plastic body material,

3,719,232 Patented Mar. 6, 1973 p CC a good sealing relation is established when the head is screwed in place. Also to conduce to such sealing and to compensate for tolerance in the threaded portions which necessarily are involved in manufacture, cooperating modified buttress type, male and female threads are provided in the bottle neck and in the head.

As hereinafter detailed, a readily assembled lever operated, return spring biased, cartridge piercing pin, repicrocably mounted in a head main passage coaxial of the threads, carries a valving element sealingly engageable with a valve seat shoulder formed by a bottom counterbore-like passage below a lateral discharge passage opening through the nozzle; while by part of the bias spring engaging structure on the upper part of the pin, the main bore is sealed, above the lateral passage, against escape of the fire extinguishing substance moving toward the nozzle. The valving head thus provided is simple in structure, further is adapted to safetying against accidental discharge by simple wedge means, and the overall structure is adapted to retention in a simple plastic stowage fixture as later described.

It is then the general object of the present invention to provide a fire extinguisher device having structure which eliminates certain marked disadvantages of comparable types of prior art devices. Another and more particular object is to provide an extinguisher structure in which the susceptibility to corrosion is minimized or obviated by useof synthetic plastic components. Another object is to provide an extinguisher Which is simple in form and which can be fabricated at comparatively low cost. Other objects and advantages will appear from the following description and the drawings, wherein:

FIG. 1 is a vertical longitudinal or axial section through a hand fire extinguisher embodying the invention;

FIG. 2 is an enlarged quasi-exploded view showing a cartridge piercing pin "and valving member assembly separated into two parts;

FIGS. 3 and 4 are respectively side elevational and plan views of a safetying wedge;

FIG. 5 is an enlarged vertical section taken similar to FIG. 1, through a discharge head and showing minor modifications from that of FIG. 1;

FIG. 6 is an enlarged axial section of the neck region of the bottle;

FIG. 7 is a plan view of the discharge head of FIG. 5;

FIG. 8 is a side elevational view of a stowage fixture with a fire extinguisher device, such as that of FIG. 1, embraced therein;

FIG. 9 is a plan view of the fixture of FIG. 8, without the extinguisher;

FIG. 10 is a vertical section through the fixture taken as indicated by the line 9-9 in FIG. 8, the dashed circle representing the outline of the device stowed therein; and

FIG. 11 is an end view of the fixture and stowed extinguisher, taken from the left of FIG. 8.

In the description of the hand type fire extinguisher device shown in the drawings as one embodiment of the invention and in the claims, for convenience the device is considered as disposed vertically as in FIG. 1, and the word top and bottom, and like terms of direction or relation to the device as a whole, are used on that assumption.

As seen in FIG. 1, the device comprises, as principal components, a cylinder type pressure bottle as a container for a fire extinguishing substance to be discharged therefrom, especially an extinguishant powder such as kieselguhr; a valved discharge nozzle and hand grip head assembly 11 screwed onto the bottle neck 12; a powder discharge riser tube 13 with the upper end engaged in the neck and extending coaxially in and substantially to the bottom of the bottle and having its lower end beveled; and a replaceable elongated pressurized gas cartridge 14, for example a carbon dioxide cartridge, the male thread head 15 of which is screwed into the bottom of a depending integral nipple or discharge tube portion 16 extending through the bottle neck from the hereinafter described discharge head body element 17.

The bottle 10 is made of a thermoplastic synthetic plastic, for example, polyethylene including preferably at least local glass fiber reinforcing as partially indicated at 18. The bottle is aptly blow molded from heated tubular stock in an appropriate mold. So also the riser tube 13 is plastic, preferably a thermoplastic such as polyethylene.

The discharge head body element 17 similarly is made of a thermoplastic, such as polyethylene, and as an integral molded piece produced say by injection molding, includes a hand grip 19 on the side opposite the radial discharge nozzle formation 20, the top of the body in the region of the grip 19 having a flat bottomed broad groove at 19a for supporting a safetying wedge hereinafter described; a small top end recess formation 21, in which is pivoted by pin 22 the actuating and control lever 23 extending adjacent the grip 19 for thumb manipulation; and the integral nipple-like coaxial tube portion 1 6 about which there is an annular bottom recess female threaded at 24 for receiving the bottle neck. In the region of nozzle 20, the head cross section is rather rectangular for purposes to be described. The groove 19a also receives the depressed lever, affording operating clearance.

A vertical passage or bore 25, intersecting the radial nozzle passage at and enlarged at 25a as though counterbored from the bottom to provide a valve seat at 25b, puts the nozzle in communication with the bottle interior through laterally opening ports 26 located in nipple 16 above the female threaded end receiving the pierceable cartridge head 15.

Between the curved inner end of the annular recess and the end of the neck 12 there is disposed a resilient gasket 27, such as an O-ring, which further may serve to seal the top end of the riser tube 13 and, where the beveled tube bears endwise against the bottle bottom, also to position tube 13, rather than positioning by pressfitting or cementing it in the neck.

Thus nipple 16 and, aligned therewith, cartridge 14 are coaxially spaced from tube 13 to provide a powder passage from the bottom of the bottle to ports 26.

The bottom end 28 of the head body element is concave, corresponding approximately to the convexity of the top end or shoulder region 29 of the bottle about the neck, and the side exterior of the body has a circumferential concavity at 30 resulting in a thin flexible circumferential tapering sharp-edged lip 31 at the bottom margin of the body, which conduces to an excellent seal of the screwed-on head to the bottle top end shoulder 29 around the neck. FIG. 5 shows attainment of a similar result by relieving further the body bottom to clear a horizontal shoulder portion adjacent to the neck.

Further to obtain a good seal between the discharge head and bottle, a modified buttress type thread engagement is used (more clearly shown in FIGS. 5 and 6); the female thread 24- in the head being of conventional buttress profile or form with horizontal and sloped sides 24a, 24b, the thread root or bottom 240 being flat; while on the neck, the top side of the male thread 31, as seen in profile, curves outwardly at 31b and downwardly to merge into the crest; which joins the bottom side 31a in profile again perpendicular to the axis. Hence as the head is screwed onto the neck, the arcuately-sectioned side of the male thread is somewhat deformable to fit the female thread and thereby attain a tight seal despite the tolerances expected in the production of the threaded parts.

To pierce the diaphragm-like end closure on the carriage head 15 for releasing gas into the bottle interior and to control the discharge of the device, the discharge head assembly (see also FIG. 2) includes a rod 32 axially shiftably centered with clearance in passage 25 and having a piercing pointed bottom end; an enlargement as a valving member 34 on the rod; and, in the top counterbore-like enlargement 250, a return biasing, spiral compression spring 40 interposed between a rod top end head enlargement formation or button 33 and a nearly hemispherical seal washer element 39, with convexity resting on the shoulder provided in 250. The rounded end button 33 advantageously has a sliding sealing engagement with 250 and has a recess 35 in which engages a rounded bottom projection 42 of the lever 23, insuring operating clearance of the lever bottom from the top end of the discharge head body.

As shown in FIG. 2, the rod 32 is conveniently made in two pieces 32a and 32b, threaded together in alignment to facilitate manufacture and assembly in the discharge head. There the head 33' is a synthetic plastic button molded as shown about an upset end of the top rod half 3212, to which the spring 40 and seal washer element then are applied to form an upper sub-assembly to be inserted from above into discharge head body 17 before application of lever 23; while a lower sub-assembly comprised of the bottom rod half 32a, with the resiliently sealing valve member 34, made of suitable plastic molded on the rod in either the pear shape of FIG. 1 or the ball of FIG. Z, and further supported by a spring ring 41 in a corresponding rod groove, is then inserted from the bottom of the body 17, and the two rod halves screwed together. Washer 39 serves to support slideably the rod 32 and under pressure of spring 40 further to seal the rod to and close passage 25.

A safetying wedge 43, as shown in FIGS. 3 and 4, provided with a finger grip hole 44 and having its apex bifurcated by a round notch 43a, is readily molded from a suitable plastic, e.g. polyethylene, in width to be readily inserted between the walls of the head groove 19a with the resilient notch arms at 43a embracing rod head button 33 and, if desired, extended to embrace the lever, for wedge retention in supporting the lever 23 in raised, nonactuatable position when the device is not beingused.

FIGS. 8-11 represent a one-piece uniformly walled stowage fitting or support bracket 46 for the extinguisher device, adapted again to be fabricated from the thermoplastic material, for example, by blow-molding, to a cradle or trough-like form providing in a top wall portion 4611, a semi-cylindrical seat rounded at its ends retentatively to embrace bottle 10' endwise and lengthwise and having one end recessed to form a slot 49 receiving the aforementioned rectangular narrowed part of the head element 17 between gripping resilient arms 48 having tips 48a narrowing the slot mouth for retention of the head. Longitudinal grooves 47a, 47b, 470, on the bottom wall and a similar top wall groove 46c confer strength and necessary rigidity. 'Dhe fittings, of course, can be provided with appropriate screw holes for securement in the environment of use.

With the wedge withdrawn, the lever 23a can be pressed down, by the thumb of the users hand gripping the handle 19, to drive the pointed rod end through the cartridge head seal disk releasing the carbon dioxide to pressurize bottle 10. The resiliency and deformability to the valving member may be such that the necessary axial piercing shift is achieved before sealing contact with seat 25b is lost to obviate need of quick lever release after piercing for avoiding excess gas and/or powder loss. Upon further downward lever shift, hence rod shift, sufficient to open the valve, the fire extinguishing powder is carried with the gas up through riser 13, ports 26, around valve element 34 and out nozzle 20 in an aimable discharge of quantity controlled by the lever depressions. Release of the lever, by action of spring 40 closing the valve, causes the valve to shut off flow.

I claim:

1. A hand fire extinguisher comprising:

a blow-molded thermoplastic synthetic plastic pressure bottle as a vessel for containing an extinguishant. and having a male threaded top end neck;

and a discharge head assembly comprising a head body screwed on the bottle neck and formed as a unitary injection molded element including a projecting hand grip, a female threaded bottom recess to receive said neck,

\ a vertical coaxial through-passage and a lateral aperture extending laterally from a middle part of the through-passage to provide a discharge nozzle, and

means for supporting a compressed gas cartridge within the bottle and with a pierceable cartridge end in opposed endwise alignment with said passage;

said head assembly further including valving rod means vertically shiftably disposed in said passage valving said passage below the lateral aperture and adapted upon downward movement, both at its bottom end to pierce the pressurized gas cartridge and also above its bottom end to open said passage for escape to the nozzle of a pressure gas stream entraining said extinguishant.

2. A fire extinguisher as described in claim 1, with:

the top end of said bottle convexly shaped coaxially downwardly of said neck;

the said head body having its underside inwardly arched toward said recess correspondingly to the contour of the upper end of the pressure bottle and having its lower exterior periphery concavely flaring downwardly and outwardly to meet the inwardly arched underside at a sharp angle, thereby forming a tapered sharp edged elastically bendable circumferential lip sealingly engaging with the convex end of the bottle when the discharge head assembly is screwed onto the neck.

3. A fire extinguisher as described in claim 1, with:

the said vertical through-passage of the head body having top and bottom counterbore-like end enlargements terminating in upper and lower shoulders respectively above and below said nozzle aperture;

the vertically shiftable rod means comprising an assembly comprised of an upper rod section and a lower rod section connected by screwing together end-toend,

the upper rod section having a button secured on its top end and provided with a central top recess, and guided in the top end of the passage,

the lower rod section having at its bottom a piercing point and about its top end supporting an injection molded pear-shaped plastic enlargement as a valving element shiftably engageable with said lower shoulder to prevent gas escape from the lower end enlargement to said noule;

said head assembly including a sealing disk seatable on the upper shoulder and sealingly slidable on the upper rod section, as a seal against gas escape from the said middle part to the top end enlargement of the said through-passage,

a return bias helical compression spring disposed about the upper said rod section and interposed between the underside of said button and the said sealing disk to seat the latter sealingly on said upper shoulder,

a manual actuating lever pivotally connected on the head body to extend across and pivot toward and away from the upper end of said passage,

the lever underside having a downwardly projecting boss engageable in the top recess of said button,

whereby said rod means may be assembled into said body by inserting said upper rod section with said spring and disk thereon into the upper end of said passage, said lower rod section with the pear-shaped valving element thereon into the lower end of said passage, and thereafter screwing said rod sections together.

4. A fire extinguisher as described in claim 1, with:

the said head body further including as the first said means an integrally molded tubular nipple portion centrally disposed in said bottom recess to be coaxially spaced from the female threads thereof, said tubular portion defining the lower end of said through-passage, and projecting through said neck into the pressure bottle;

said tubular portion having its lower end threaded for an aligned screw connection securement of a said gas cartridge with its upper end complementarily threaded, and

at least one radial escape opening through its wall,

above its said threaded lower end; and

a riser tube with upper end supported in said neck,

extending down into said bottle and substantially coaxially spaced around said tubular portion and a said cartridge secured thereto.

5. A fire extinguisher as described in claim 3, having a safetying element inserted between the pivoted actuating lever and the top end of the head body to secure the lever against extinguisher actuating movement.

6. A fire extinguisher as described in claim 5, with:

the top end of the said head body having a grooved formation in which the pivoted actuating lever is receivable upon full depression, said groove formation adapted to serve as a seat for a wedge inserted under said lever as the said safetying element; and a said wedge provided at its outer end with an aperture horizontally transverse to its longitudinal direction as a finger grip. 7. A fire extinguisher as described in claim 5, with: said safetying wedge having its thinner inner end notched to resiliently retentively grip a part of said head assembly when inserted in safetying disposition under said lever.

8. A fire extinguisher as described in claim 1, having the upper part of said discharge head body, above the region of its screw connection to the bottle, provided with a generally rectangular cross-section elongated in the direction of extent of said lever; and

in combination with a one-piece fire extinguisher receiving storage bracket of cradle-like form;

said bracket shaped to embrace the said bottle lengthwise and at both ends and having one end recessed to form a rectangular slot formation shaped to receive and resiliently retentively grip the corresponding rectangular cross-sectioned part of the discharge head body.

9. The fire extinguisher and bracket combination of claim 8, having said bracket molded of a thermoplastic material.

10. A fire extinguisher as described in claim 2, wherein the threaded formations of said male threaded neck and of the female threaded bottom recess of said discharge head body have a modified buttress threaded engagement, with the female thread generally of conventional buttress form and the male thread having that side, which in a normal buttress thread slopes from the root to the crest, as its top side and having a convex section,

whereby upon screwing the head onto the bottle, the

convex side of the male thread is slightly deformable against the corresponding side of the female thread conducive to an improved sealed relation between 3,051,652 8/1962 Olandt 16931 R the discharge head and the bottle. 3,105,458 10/1963 DOWIlham 169-31 R X References Cited 1 380 055 IO/EIFGN PATENTS 169 31 UNITED STATES PATENTS 5 "f' 2,739,917 3/1956 Schulze 220-DIG 14 M HENSON WOOD 3 251 420 5/19 Rodgers 169 31 R T. C.. CULP, JR., Assistant Exammer 2,904,305 9/1959 Novotny 16931 R X 3,209,949 10/1965 Gurtler 169-31 RX 10 2, 10/1959 Duggan et 16931 R 16931 R; 220-1110 14; 222-541; 239-309

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