US2564733A - Discharge head and grip for portable fire extinguisher - Google Patents

Description

Aug. 21, 1951 G. SIPKIN DISCHARGE HEAD AND GRIP FOR PORTABLE FIRE EXTINGUISHER Filed June 22, 1,949

24 38 4a a? 22 51mg INVENTOR.

eorge Sipkin ATTORNEY disabling efiect.

Patented Aug. 21, 1951 UNITED STATES PATENT OFFICE DISCHARGE HEAD AND GRIP FOR PORT- ABLE FIRE EXTINGUISHER (Granted under the :act of March 3, 1883, as

amended April 30, 1928; 370 G. .757)

)1 This invention relates to portable tire extinguishers with special application to the discharge head thereof and to means for. facilitating portafrom the fact that the carbon dioxide in liquid form has a boiling point of 108 F. and a pressure at ordinary room temperature of between 800 and 900 pounds per square inch. Since the most efiective .use of the apparatus is obtained by playing the discharge as .close to the fire as possible, and since moreover, the vapor pressure of the contained liquid varies directly as the temperature, it is apparent that the danger of explosive rupture of the container is present and that this danger is most imminent at the time of application of the extinguisher.

In currently used apparatus the danger f tank rupture is provided for by use of a frangible disk which yields at the danger pressure point. Heretofore, however, this blow-disk has been so placed that should fracture occur during use of the extinguisher, the carbon-dioxide sprays on the hands of the operator with acute The present invention therefore, contemplates structure wherein the blow port directs spray away from the operator, and moreover, at the moment of outlet control valve actuation by the operator, a choke is made effective to remove the pressureon the blowadiskor reduce or substantially eliminate the gas flow at the blow port if rupture occurs, thus preventing disabling of the extinguisher due to rapid uncontrolled escape of liquid. 'The invention also provides accessory tank support means enabling transport and support of the tank whether or not the discharge head is in place by one or both hands While at the same time cooperating to produce actuation of the outlet valve when the discharge head is in use.

The objects of the invention therefore are to provide fire extinguisher apparatus with means for protecting the operator from extinguisher spray; to provide apparatus for eliminating blow out during use or retarding liquid leakage at the blow port in case of blow out at the time the extinguisher is put into use; to provide tank support means for facilitating easy handling of the equipment before and during use; and also to provide a simple method of visual inspection of the blow-disk when the discharge head is partly "disass mbled. Other objects and features of the invention will appear on consideration or the following description of a preferred embodiment :Of the invention as illustrated in the accompanying sheet of drawing in which:

Fig. ,1 is a plan view of the dischar e head of the extinguisher;

Fig. '2 :is a sectional view taken on lines 2-2 of .Fig. 1 showing the valve mechanism;

Fig. 3 is a detail section on lines 3-:3 of Fig. 2 showing the attachment device of the tank support handle; and

Fig. 4 is anenlareed detail section of the blow port choke valve in operated condition.

Referring :now to the drawings, in which like numerals throughout the several figures designate like parts, and particularly to Fig. 2, the eatingu'isher tank 5 is constructed of pressure resist! ant material such as sheet steel :with a con stricted neck 6 at one end provided with an opening 1 internally threaded at its .outer end. An annular :grnove 8 :is cut in the outer race of tank neck '6 in this groove strap clamp 9 having out turned adjoining ends 1:9, isadjustably held by bolt II, as indicated. The midsection of the clamp is provided with .a support tab 12 to which the support handle [:3 is .pivotally attached. handle is preferably fashioned of sheet :metal with the .outer .end It inturned tdward the tank 5 to facilitate grasping of the handle, and the other end formed with side plates 15 which are ia-pertured to receive the pivot .pinl- 6 rota-table in an opening formed in tab 12. The top .end .111 .of the handle is extended beyond the pivot to form a stop :for the handle when flit-ted into abutment with neck [5 whereby .a firm carrying means for the tank is provided. A .bail it having a transvserse section I9 is pivotal ly attached to the side of the handle for holding the tank discharge port in open post tion as will hereinafter he more fully described. Ilf desired, the annular groove 8 may be omit-ted from the neck =6 and the st-rap clamp 9 may be frictionally clamped 'to the neck.

The discharge head 20 of the apparatus is roughtly I -shaped with an upright supporting section :21, left and right top sections '22 and '23 and a central head 24 at the {function of these.

various sections. The upright section 2| is provided with outer threads at thelower end thereofthis upright section, terminating at the lower end in a threaded connection to the syphon tube 26, this tube extending to a point adjacent the tank base, and the bore terminating at the upper end in a central cavity or chamber 21. This chamber 21 is extended laterally into and through the T- sections 22 and 23,- to the left section 22 to supply the blow-port and to the right section 23 to supply the discharge valve. In forming the discharge valve duct the chamber 21 is constructed to make an outlet chamber 28 to which the discharge pipe unit 29 (Fig. 1) with the diffusing button 38 and horn 59 is attached, all as well known in the art.

A further constriction in the T-section 23 to the right of chamber 28 forms an opening 3| for the valve stem 32 which is slidably mounted therein; and the opening 3| is expanded into a larger cavity to receive the stem gasket 33 and the gasket nut 34. The stem end is rounded and projects outwardly from the gasket nut to cooperate with the operating lever 35 as will be described more fully hereinafter.

The central chamber 21 is enlarged approximately midway to the end of T-section 22 to receive main plug washer 36, and the threaded end 31 of main plug 38. This plug is axially apertured to form a duct extending completely through the plug to the central chamber 21. The outer section is internally threaded to receive blow out plug 40 which, in turn, is also axially apertured from its inner end to a point adjacent the outer end where radial outlet ducts 4| are formed. A copper blow-disk or element 42, supported by washer 43, extends completely over the inner end of blow-plug 40 and is closely held between the plug and the offset shoulder formed by the smaller intermediate duct section 44 with the outer duct section. This blow-disk is made of thin copper capable of withstanding pressures up to 3000 pounds per square inch and is gold coated to prevent corrosion by the gases and spray.

Inner intermediate duct-section 45 is separated from the blow port duct section 44 by a conical section 44a and forms a cavity, larger in diameter than section 44, between section 44 and central cavity 21 for enclosing the blow out choke valve or pin 46. This pin is a straight cylindrical rod mounted at one end on a central extension 41 from the back plate of valve 48. The pin has a rounded outer end which is adapted on axial outer movement to penetrate the duct sections 44a and 44, this penetration being facilitated by the conical shape of section 44a. The diameter of pin 46 is only slightly less than the inner diameter of duct 44 as shown in Fig. 4 so that fluids may move from the inner cavity 21 past the pin when inserted in the duct 44, should the disc 42 rupture, but at a rate effectively reduced over that when the pin is withdrawn. Furthermore, as the end of the pin 46 penetrates further and further into the conical section 44a, the pin increasingly restricts the fluid passage between duct sections 44 and 45 so that a variable choke effect is produced to gradually reduce the fluid pressure tending to rupture disc 42 as will appear hereinafter.

The valve 48 consists of a cup shaped element having a back base attached to the choke pin 48 and a cup space for reception of the seal element 49. This element is adapted to engage the valve seat 50 formed at the junction of the central cavity 21 and adjoining intermediate cavity 28. A coil spring enclosing valve extension 41 and 4 extending between the valve back plate and the shoulder between cavities 2'! and 45 normally holds the valve 48 in closed position. The valve 48 is connected to the valve stem 32 by means of a short stem extension 52 of reduced diameter which terminates in a holding groove and shoulder for the valve seal and a threaded end 53 for engagement with a threaded axial opening in the valve extension 41. It thus appears that the valve stem 32, the stem extension 52, the valve 48, the valve extension 41 and the choke pin 46 form together a rigid unit. It appears also that when the spring 5| holds the valve 48 seated, the choke pin is free of duct 44, as shown in Fig. 2, but when the valve moves to the left due to compression of stem 32, the choke pin 46 enters further into conical section 44a and eventually into section 44 to restrict free movement of liquid to the blow duct in case of blow out as shown in Fig. 4.

Means for actuating the valve stem 32 against tension of spring 5| is provided in the valve lever 35. This lever includes an axially extended handle 54 having cross bail stop 55 at one end, lateral juxtaposed side openings to receive the pivot pin 56 at the other end, a pivot end extension 51 forming a lever limit stop for up movement, and a valve stem contact head 58 adjacent the pivot end of the lever. Downward movement of the lever causes engagement of contact head 58 with the outer end of valve stem 32, thereby opening the valve and moving the choke pin 46 into the duct sections 44a and 44 in an amount proportional to the opening of valve 48. In order to prevent accidental closure of the lever the side walls of the lever are apertured in such manner that when a pin 68 is inserted in these apertures, the pin and lever are stopped against the Valve plug 34. One end of the pin 60 is coiled and a chain 8| fixed to the head prevents accidental removal and loss of the pin. In addition, to prevent loss in transit a detachable wire-lead seal 6| is employed to hold the pin in place.

The operation of the discharge head as a complete unit may now be described, it being assumed that the tank or container 5 has been fully charged with liquid carbon dioxide. The operator grasps handle I 3 and moves the tank to such proximity to the fire that the tank discharge may be applied at the base or edge of the flame, the lock pin 60 being preferably removed on the approach thereto. The lever 35 is then depressed opening the valve and permitting the liquid chemical to diffuse through the outlet horn 59. On suffocation of the fire, the lever is permitted to raise and the coil spring 5| thereupon closes the valve, and this operation may be repeated until the supply of liquid is exhausted.

Should the pressure inside the tank become excessive due to the close proximity of the fire and before the operator has had an opportunity to apply the extinguisher, the blow disk may yield. In this case, since the outlet ducts 4| of the blow plug are in a vertical plane, or lie transversely to the handle l3 and lever 35, there is no direct application of the highly freezing liquid to the hand of the operator who holds the apparatus. Moreover, by rupture of the blow disk the apparatus is not wholly disabled, since by operating the lever the outlet duct 44 to the blow port is choked and a substantial flow of extinguisher is maintained in the main valve port. It is likewise apparent that when valve 48 is open and is relieving the pressure inside the container 5, the blow port 44 is either substantially or partially blocked thereby reducing the likelihood of rupture of the disk 42 aeegeea at this. time, the amount ofblocking bei'rrgin proportion to the opening of the valve. Thus, the general efiiciency of the extinguisher is maintained irrespective of blow disk fracture, and in--.

dependently of whether fracture occurs directly before or after main valve actuation,- and that likelihood of the latter occurring is greatly reduced. If the operator desires to leave the extinguisher with the valve open, he hooks the bail 18 over the stop 55 on the valve handle;

Certain advantages of the described apparatus may be here pointed out. The choke pin 36 serves not onlyto control escape of extinguisher fluid as described above but also serves as aremoval pin for the valve structure since, on unscrewing of main plug 38, the pin may be seized and the entire valve unit removed. Further it is noted; that to inspect the blow disk d2, it is unnecessary to unscrew the blow-out plug 3% after the main plug 38' has been removed as visual inspection of the disk 42 may be made through the duct 44 whereby the condition oi the gold coating on the disk may be determined.

Also the arrangementof the handl'eis important in that it is susceptible to circumferential adjustment. Where a single hand operation is desired, the handle It may be set directly beneath the lever 35 as shown in Fig. 1 in which position the tank may be transported and the lever actuated by a single hand. Where two hand use is desirable, the groove clamp 9 is adjusted to obtain an angular diversion between handle and lever, in which position the tank may be transported by the left hand, for example, and the right hand used to remove the lock pin 69 and manipulate the lever. The bolt H may be left loose so that the handle It may be readily moved to the position desired.

While a groove on the tank neck is described,

obviously the clamp may be secured on the un grooved outer neck surface. Note is made also of the fact that handle attachment to the tank neck insures easy transportation means when the discharge head is removed; and that support means secured directly to the steel tank is more assured and possesses greater strength than support means attached to the brass extinguisher head 20 screwed into the tank neck. Carbon dioxide has been referred to as the extinguisher chemical but it is apparent that other chemicals operating on the pressure principle may be safely controlled by the described apparatus.

Modifications other than as mentioned may of course be made by those skilled in the art and it is understood therefore that, within the scope of the appended claims, the invention may be practiced otherwise than as specifically described.

The invention described herein may be manufactured and used by or for the government of the United States of America for governmental purposes without the payment of any royalties thereon or therefor.

What is claimed is:

1. A discharge head for a fire extinguisher tank provided with a fluid outlet comprising a terminal head having a chamber therein, a blow port connected by a duct to said chamber, a frangible disk normally closing said blow port, an outlet port in communication with said chamber, a valve in said chamber for normally closing said outlet port, and means attached to said valve and associated with said duct for obstructing fluid flow therethrough when the valve is open.

2. A discharge head for a fire extinguisher tank provided with a fluid outlet comprising a terminal pl ug connected to said outlet having a vaive chamber therein; a connecting duct between the chamber and tank outlet, a blow port connected to said chamber, a blow disk normally closing said blo'wport, an outlet port connected to said chamher, a main valve normally closing the passage'' way between the chamber and outlet port, a

spring normally seating said valve in closed position, a choke valve fixed to said main valve adapted to entersaid blow port to retard movement of fluid therethrough on blow disk rupture and main val-ve opening, and a lever for moving said main and choke valves to open said main valve and to close said choke valve.

3-, The discharge head as described inclaim 2 with the outlet ducts of the blow port extending approximately transversely to said lever.

4. The discharge head as described in claim 1 in which said blow port is obstructed by said means proportionately tothe amount the valve is opened.

5. The discharge head as described in claim ,2 in which movement of fluid through said blow port is controlled by said choke valve in propor tion to the movement of said main valve;

6. A discharge head for a fire extinguisher tankprovided with a fluid outlet, comprising a terminal head having a chamber therein, a blow port connected to said chamber, a yieldable blow element normally closing said blow port, an outlet port connecting to said chamber, a valve for normally closing said outlet port, and means including valve stems associated with said valve for substantially closing said blow port and opening said valve.

'7. A portable fire extinguisher comprising a tank for containing extinguisher fluid, a discharge head having a chamber therein, a duct connectin said tank and chamber, a blow port connected to said chamber, a blow element normally closing said blow port, an outlet port connected to said chamber, a valve for normally closing said outlet port, means for operating said valve, means connected to said valve for obstructing said blow port upon opening movement of said valve, means for supporting said tank with one hand, means for manipulating said valve and blow port obstruction means with the other hand, and means attached to said handle and valve operating means for selectively holding the valve in open position.

8. A discharge head for a fire extinguisher tank provided with a constricted outlet port, comprising a terminal plug removably attached to said port having a central valve chamber with four aligned openings including a bore connecting the chamber and tank port, a duct connecting the chamber and discharge head port, a .bore forming a bearing for a valve stem, and an opening for receiving a side plug, a side plug removably attached in said terminal plug opening, and having a two diameter duct therein communicating with said chamber, and a recess in the head thereof communicating with said duct, a blow disk, a blow plug removably insertible in said recess for retaining said blow disk in obstructive position for fluid flow from said chamber, said blow plug having a main duct aligned with said openings and transverse radial ducts communicating with said side plug duct on rupture of said blow disk, a valve seat formed in said chamber surroundin the inlet from the chamber to the discharge head port, a valve normally resting on said seat to close said outlet head port, a valve plug attached to said terminal plug and having aromas abore therein in alignment with said valve bear-' ing bore, a ring gasket between the valve and terminal plugs, a .valve stem attached to said valve and slidably positioned in said valve stem bearing and valve plug bore with the free stem and extending outwardly beyond said valve plug, a choke pin attached to said valve and extending into the nearer and larger of said side plug ducts, a spring in said chamber normally holding said valve in closed position, and a lever for engaging and movingsaid valve pin end inwardly, whereby the valve is opened and the choke pin is forced into the farther and smaller of said side plug ducts.

9; A portable fire extinguisher comprising a tank adapted to hold extinguisher fluid under pressure, said tank comprising a tank outlet for said fluid having a restricted neck portion, said neck portion having an outer annular groove and an internal screw thread, said fire extinguisher further comprising a discharge head having a threaded stem portion removably screwed into said neck portion, said discharge head comprising a valve chamber and a main discharge outlet therefrom, a duct connecting said valve chamber with said tank outlet, a valve normally closing said discharge outlet and a lever mounted on said head for operating said valve, a clamp positioned in said annular groove, a handle attached' to said clamp for lifting said tank with or without said discharge head, said lever being vertically spaced from said clamp a distance enabling an operator to grasp said lever and handle in one hand, and means for adjusting said clamp rotatively around said tank neck to position the handle attached to the tank in axial alignment with the valve lever attached to the head whereby they can be squeezed together by the hand of the operator for operating the lever to open said valve against the pressure inside said tank.

10. A portable fire extinguisher as defined in claim 9 but further characterized by a bail attached to said handle of a size substantially equal to said distance, and means on said lever for reception of said bail for holding said lever in the valve open position.

GEORGE SIPKIN.

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

UNITED STATES PATENTS Number Name Date 2,067,829 Denne Jan. 12, 1937 2,375,615 Boal May 8, 1945 2,495,688 Blakeslee Jan. 31, 1950

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