US2592029A

US2592029A - Dry powder fire extinguisher

Info

Publication number: US2592029A
Application number: US155817A
Authority: US
Inventors: Edward H Hansen
Original assignee: Elkhart Brass Manufacturing Co LLC
Current assignee: Elkhart Brass Manufacturing Co LLC
Priority date: 1950-04-14
Filing date: 1950-04-14
Publication date: 1952-04-08
Anticipated expiration: 1969-04-08

Description

April 8, 1952 E. H. HANSEN 2,592,029

DRY POWDER FIRE EXTINGUISHER Filed April 14, 1950 Patented Apr. 8, 1/952 UNITED STATES PATENT OFFICE 2,592,029 par rownEa man ExrlNcursHEa Edward H. Hansen, Elkhart, Ind., asslgnor to Elkhart Brass Manufacturing Company, Inc., Elkhart, Ind., a corporation of Indiana Application April 14, 1950, Serial No. 155,817-

. 5 Claims.

This invention relates to portable fire extinguishers and refers more piirticularly to the type of chemical fire extinguisher which employs a dry powder extinguishing agent and an inert gas under pressure for delivering the agent to the site of the fire.

The most compact type of dry powder re extinguisher is that in which' a vcartridge or bottle of inert gas (usually carbon dioxide) is supported inside aV closed substantially cylindrical tank or vessel containing a charge of a powdered extinguishing agentv such as sodium bicarbonate. -fw

Inert gas under high vprcsliire, escaping from the discharge port of the cartridge, carries the powder out of an outlet in the; vessel in a steady stream which continues as long as the inert gas has substantial pressure. Aiire extinguisher of this type is shown in the patent to Meigsl No. 1,987,785.

In past nre extinguishers of this type, however, it has not been possible to regulate the rate of escape of inert gas from the cartridge, and consequently it -has not been possible to regulate the rate of discharge ofthe extinguishing agent or to interruptits flow. This disadvantage was especially serigus where the extinguisher was needed for 4fighting a number of small, dispersed tires, since Athe ow of extinguishing agent could not be interrupted during the periods when the extinguisher was being moved from one fire to another, and consequently a valuable portion of Vthe charge was wasted. Moreover, the entire charge of such an extinguisher was dissipated in lighting a single fire, no matter how smalhand it was then unavailable for any further use until recharged.

By contrast, it is an object of this invention to provide a portable fire extinguisher of the dry chemical type in which the rate of discharge of the extinguishing agent may be controlled or its flow interrupted a'sdesircd.

Another object of this .invention resides in the provision of a portable ilre extinguisher of the dry chemical type which isA compact and easy to operate so that it may be readily brought to the site of a re and quickly put into action.

With the above and other objects in view, which will appear as the description proceeds, this invention resides in the novel construction. combination and arrangement of parts substantially as hereinafter described and more particularly defined by the appended claims, it being understood that such changes in the precise embodiment of the hereindisclosed inven- 2 tion may be made as come within the scope or the claims. A

The accompanying drawing illustrates two complete examples of the physical embodiment of the invention constructed according to the bestmodes so far devised for the practical application of the principles thereof, and in which:

Figure 1 is a vertical sectional view through a fire extinguisher embodyingthe principles of this invention;

Figure 2 is a detail sectional view. upon an enlarged scale, of the valve mechanism of the fire extinguisher of this invention; and

Figure 3 is a detail sectional view of a modified embodiment of said valve mechanism.

Referring now more particularly to the accompanying drawing, in which like numerals designate like parts, the numeral 5 indicates generally a substantially cylindrical tank or vessel adapted to contain a charge of dry powder re extinguishing agent such as sodium bicarbonate and having an outlet 6 at its bottom through which the powder is adapted to be discharged. A ilexible hose 1, connected to the outlet, enables the discharging stream of chemical to be accurately directed upon a fire.

The tank 5 is preferably made of sheet rmaterial, in conformity with conventional with conventional practice, and a heavier externally threaded neck 8 is bonded to its open top to accommodate an internally threaded cap 9 furnished with a ring-like handle II to facilitate removal and replacement of the cap for charging the extinguisher and to enable it to be readily carried from place to place. A resilient annular gasket l0, compressed between the top of the cap and the rim of the neck insures a gas-tight seal between them.

A Well-like cylindrical carrier I2 is removably supported within the vessel from the top thereof by means of a ange I2' resting on the lugs 8'. This carrier is easily inserted into the vessel after the vessel has been charged with powder and when in position provides a receptacle foran inert gas bottle or cartridge I3 inserted therein in an upright position, with its discharge port I4 lowermost. The carrier is substantially longer than the cartridge so that the cartridge may have limited axial movement and it has a diameter somewhat greater than that of the cartridge to allow gas escaping from the discharge port` to pass upwardly around the cartridge and out of the carrier or receptacle, into the tank, through outlets I5 in the wall of the receptacle, near the top thereof.

A row of circumferentially spaced spacer studs or bumpers I6 hold the cartridge centered in the receptacle and allow it to move freely up and down therein.

It is to be noted that the gasket I is suiliciently wide to overlie the outer marginal edge portion of the upper surface of the ilange I2 as well as the rim of the neck 8 to thus provide a completely gas-tight seal for the top of the vessel.

The valve by means of which escape of inert gas from the cartridge is controlled comprises a resilient gasket I9 of rubber or neoprenef which is aflixed to the ilat bottom of the carrier I2 in position to cooperate with a shoulder or rim 20 around the discharge port of the cartridge. It will be seen that the gasket and shoulder together deiine an annular outlet valve through which inert gas from the cartridge must escape in order to pass upwardly around the cartridge and thence out of the ports I in thhe wall of the carrier I2.

One end of a coiled compression spring 2| rests on the bottom of the carrier I2 and its other end bears against a flange 22 on the cartridge to bias the cartridge upwardly, against its own weight, to a position in which the valve is wide open. A drive screw 23 threaded through the center of the cap 9 is adapted to drive the cartridge downwardly, against bias of the spring 2|, toward the valve-closed position. The drive screw is provided with a convenient handle 24, accessible at the top of the tank, and its lower or inner end has a suitably adapted socket 25 which rmly engages the hemispherical top of the discharge cartridge.

A tapered puncturing pin 26 is mounted on the bottom of the carrier in position to engage the frangible seal 21 which normally closes the discharge cartridge, to puncture the seal when the cartridge is driven down to the position in which its shoulder or rim 20 completely engages the gasket I9 to closes the valve mechanism. The pin is provided with longitudinal grooves or flutes 28 to permit the instantaneous escape of gas as soon as the drive screw is retracted suiliciently to enable the spring to raise the cartridge enough to open the valve defined by the shoulder 20 and the gasket I9.

The frangible seal 21 of the cartridge or bottle shown in Figure 2 comprises a disc or membrane of relatively soft metal which is clamped between an annular ledge or shoulder 29 on the discharge port of the bottle and an apertured plug 30 threaded into the mouth of the outlet.

' In the modified embodiment of the valve mechanism shown in Figure 3 the shoulder 29' is relatively Wide and is chamfered at its inner periphery as at 32. The chamfered portion of the shoulder thus backs up the ruptured edge of the seal disc 21', which then serves as'a valve seat capable of cooperating with an uniluted tapered puncturing pin 26' to provide a needle valve.

It will be seen that in this embodimentof the invention no resilient gasket is required in the lbottom of the well-like receptacle or carrier I2 since the puncturing pin, together with 'the edges of the frangible seal after the latter has been ruptured, functions as a valve mechanism whereby the discharge of gas from the cartridge may be regulated or stopped completely.

Operation of the extinguisher of this invention is exceedingly simple. In order to ll it with powder the cap 9 is unscrewed from the top of the tank, and the carrier I2 is lifted -outof the 4 tank to enable a charge of powder to be poured into the tank. The carrier is then replaced, a filled gas cartridge inserted therein and the cover is firmly screwed back into place to close the vessel.

In operating the extinguisher it is carried as near to the site of the iire as possible and then the drive screw 23 is screwed down by means of the handle 24 until the puncturing pin 26 ruptures the frangible seal of the cartridge. In each of the embodiments the drive screw is then retracted, by turning it in the opposite direction, until a satisfactory rate of flow of the re extinguisher agent from the hose outlet is established. The ow of powder may be diminished at any time or even stopped entirely by turning the drive screw inwardly so as to push the cartridge down toward the closed position of the valve.

From the foregoing description taken together with the accompanying drawing it will be readily apparent that this invention provides a compact portable re'extinguisher of the dry chemical type wherein the rate of escape of inert gas from the cartridge may be regulated or stopped at will to thus enable complete regulation of the rate of discharge of powder from the extinguisher.

What I claim as my invention is:

1. A valve structure for controlling the discharge of gas from a cartridge of the type having an outlet at one of its ends normally closed by a frangible seal, said valve structure comprising: a valve body including a hollow receptacle closed at one end and open at the other end to enable a gas cartridge to be freely inserted endwise'thereinto With its outlet facing the closed end of the receptacle, and a cover closing said open endof the receptacle; the valve body having escape ports therein through which gas in the interior of the receptacle may escape to the exterior thereof; a resilient gasket inside the -closed end of the receptacle cooperable with the outlet of the cartridge to define a valve through which gas may' escape from the cartridge into the interior of the receptacle; spring means in the closed end of the receptacle to bias the cartridge toward the covered end of the receptacle, away from said gasket, to a valve open position; a manually operable drive screw threaded in the cover and extending into the receptacle to bear against the adjacent end of a cartridge in said receptacle, said screw being cooperable with the spring means through the cartridge to effect regulation of said valve; and a puncturing pin immovably carried by the valve body inside the receptacle, at the closed end thereof, with its point projecting through said gasket toward the covered end of the receptacle, for rupturing the frangible seal on the cartridge when the latter is driven against the puncturing pin by said drive screw.

2. A valve structure for controlling the discharge of gas from a cartridge of the type having an'outlet at one of its ends normally closed by a frangible seal, said valve structure comprising: a valve body including a hollow receptacle closed at one end and open at the other end to enable a gas cartridge to be freely inserted endwise thereinto with its outlet facing the closed end of the receptacle, and a cover closing said open end of the receptacle; the valve body having escape ports therein through which gas in the interior of the receptacle may escape to the exterior thereof; a resilient gasket inside the closed end of the receptacle cooperable with the outlet of the cartridge to dene a valve through which gas may escape from the cartridge into the interior of the receptacle; spring means in the closed end of the receptacle to bias the cartridge toward the covered end of the receptacle, away from said gasket, to a valve open position; manually operable means carried by the cover, having a part inside the receptacle movable toward and from the closed end thereof and engageable With the adjacent end of a cartridge in the receptacle to hold the cartridge in different positions of endwise adjustment relative to the receptacle, so that said cover carried means is cooperable with the spring means through the cartridge to effect regulation of said valve; and a puncturing pin immovably carried by the valve body inside the receptacle, at the closed end thereof, with its point projecting through said gasket toward the covered end of the receptacle, for rupturing the frangile seal on the cartridge when the latter is driven against the puncturing pin by said cover carried means.

3. The valve structure defined in claim 2 further characterized by the provision of longitudinal grooves in the puncturing pin to facilitate escape of gas from the cartridge when the frangible seal is ruptured by the pin.

4. A valve structure for controlling the discharge of gas from a cartridge of the type having an outlet at one of its ends normally closed by a frangible seal, said valve structure comprising: a valve body including a hollow receptacle closed at one end and open at the other end to enable a gas cartridge to be freely inserted endwise thereinto with its outlet facing the closed end of the receptacle, and a cover closing said open end of the receptacle; the valve body having escape ports therein through which gas in the interior of the receptacle may escape to the exterior thereof; spring means in the closed end of the receptacle to bias the cartridge toward the covered end of the receptacle; manually operable means carried by the cover having a part inside the receptacle movable toward and from the closed end thereof and engageable with the adjacent end of a cartridge in the receptacle so as to cooperate with the spring means in providing for endwise adjustment of the cartridge in the receptacle; and a puncturing pin immovably carried by the Valve body inside the receptacle, at the closed end thereof, said puncturing pin having a substantially conical point projecting toward the covered end of the receptacle for rupturing the frangible seal on the cartridge when the latter isfdriven against the puncturing pin by said cover carried means, and said conical point restricting the punctured opening by an amount depending upon the position in Which the cartridge is held jointly by the cover carried means and said spring means.

5. The valve structure set forth in claim 4 wherein the manually operable means carried by the cover comprises a drive screw threaded in the cover and extending into the receptacle to bear against the adjacent end of a cartridge in said receptacle.

EDWARD H. HANSEN.

REFERENCES CITED The following references are of record in the le of this patent:

UNITED STATES PATENTS