US2684180A

US2684180A - Stored pressure medium container with discharge control

Info

Publication number: US2684180A
Application number: US137847A
Authority: US
Inventors: Frank B Allen
Original assignee: CO Two Fire Equipment Co
Current assignee: CO Two Fire Equipment Co
Priority date: 1950-01-10
Filing date: 1950-01-10
Publication date: 1954-07-20
Anticipated expiration: 1971-07-20

Description

July 20, 1954 F. B. ALLEN 2,684,130

STORED PRESSURE MEDIUM CONTAINER WITH DISCHARGE CONTROL Filed Jan. 10, 1950 2 Sheets-Sheet 1 a 12-? I 4 "i 4 4 l .xl 4 f i Z j 2 INVENTOR. FRANK 5/1445 BY Vzg A TTOR/Vf) July 20, 1954 F. B. ALLEN 2,684,180

STORED PRESSURE MEDIUM CONTAINER WITH DISCHARGE CONTROL Filed Jan. 10, 1950 2 Sheets-Sheet 2 3 4}? 50 40 a. 49 E I g 3.9

I g 46 4 4g V145 INVENTOR.

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Patented July 20, 1954 UNITED STATE RATENT OFFICE STQRED PRESSURE MEDIUM CQNTAINER WITH DISCHARGE CONTROL Application January 10, 1950, Serial No. 137,847;

G Glaims.

The present invention relates to stored pressure medium containers with discharge control such as are used principally for pressurizing fire extinguishers or other devices containing an agent to be expelled by pressure means.

The containers are charged with a compressible fluid at a high pressure and are provided with closure means so that the fluid may be released. as desired at a predetermined and controlled rate of discharge. When a container is used in a fire extinguisher it is generally necesthat ample fluid pressure be available to discharge the fire extinguishing agent in less than a minute. Futhermore, it is important that a lealcprooi seal be provided for the fluid as the device, in the case of a fire extinguisher, may not be used for a year or more, but the stored fluid always must be available for instant action in the case of a fire. While seat valve closures have been provided for some containers, it has been found desirable in the smaller units to provide a disc seal.

Among the advantages of the disc seal is that when properly made it almost always remains leainproot Another advantage is that the disc provides a safety outlet for the release of the fluid in the event the pressure in the container builds up to an unsafe amount such as from a high temperature. Still another advantage is that the stored fluid may be released instantly upon the rupturing of the disc by a puncturing member.

Although the disc acts as a safety valve to relieve an excessive pressure, such as occur .sage by making it of small diameter or by placing an orifice disc therein so as to limit the rate of discharge of the fluid and thus limit the recoil action. With such constructions difficulty has been found in some cases in that the charging rate is very sl w, thus considerably adding to the charging and recharging costs. Also, with the prior constructions, it is difficult to drain out any water or other material which may have entered the container either before its original charge or during the period while its disc was ruptured, but before recharge, without devalving the container.

The present invention aims to overcome the Rd difiiculties and disadvantages of prior devices by providing a container having a limited discharge rate, yet which may be rapidly charged or recharged.

Another object of the invention is to provide a container having a predetermined discharge rate.

Another object of the invention is to provide a disc-sealed container which is discharged at a safe rate when the disc is ruptured from internal pressure and which may be discharged at a faster rate when the disc is ruptured by the usual puncturing member.

The invention may be incorporated in containers providing either a high or a low rate of discharge depending upon the requirements of the devices with which they are to be used. For example, if a container is to be used to pressurize a powder fire extinguisher, a high rate of discharge is preferable to agitate and fluff-up the powder prior to its expulsion. In the case wherein a container is to be used to pressurize a water extinguisher alow rate or" discharge is preferable as the water is practically non-compressible and non-absorbable, thus a high discharge rate of the container would result in excessive pressurizing and stressing of the walls of the extinguisher. Various forms of the invention may be provided to take care of the various requirements.

These objects are accomplished by providing a stored pressure medium container having closure means such as a sealing disc with a fluid flow limiting member in proximity to the sealing disc and removable therewith for ease in replacement. The edge of the fluid flow limiting member may be used as the gasket for the sealing disc. In releasing the fluid from the container a puncturing member is adapted to rupture the sealing disc, and, with some forms of the fluid flow limiting member, to penetrate it to provide an increased rate of discharge.

The invention is advantageous in that a throwaway unit may be provided at low cost thus rendering it feasible to provide a new fluid flow limiting means with each recharge overcoming any possible difiiculty which may arise to the orifice because of corrosion damage or damage from mishandling of the units.

Another advantage of the invention is that a stored pressure medium container is provided which may have a predetermined discharge rate but which is suitable for use with various devices having differing requirements as to the discharge rates of their respective pressurizing mediums,

the variation in the discharge rate being achieved merely by varying the size and/or travel of the puncturing member of the discharge device.

ther objects and advantages of the invention will be apparent from the following description and from the accompanying drawings which show, by way of examples, embodiments of the invention.

In the drawings:

Figure 1 illustrates a fragmentary, vertical sectional view of a powder fire extinguisher incorporating a stored pressure medium fluid container made in accordance with the invention.

Figure 2 is an enlarged view of a portion of the structure shown in Figure 1, illustrating in dotted lines the puncturing member at the bottom of its downward stroke.

Figure 3 is an enlarged sectional view through a sealing disc and fluid flow limiting member or orifice disc, in accordance with the invention, in which the center portion of the member is dished.

Figure 4 is a bottom view corresponding to Figure 3.

Figure 5 is asectional view of the fluid flow limiting member or orifice disc having a dished center portion, and made with a reduced portion about the orifice.

Figure 6 is a bottom view corresponding to Figure 5.

Figure '7 is a sectional view of a form of the fluid flow limiting member in accordance with the invention, made of a fiat thin piece of material.

Figure 8 is a bottom view of the structure shown in Figure '7.

Referring to the drawings, there is shown in Figure 1 a powder fire extinguisher l0 pressurized by a stored pressure medium fluid container ll made in accordance with the invention.

The powder fire extinguisher I0 is illustrated to show a use for the stored pressure medium fluid container H and includes a standard shell l2 adapted to contain a fire extinguisher powder which is charged through a filling opening it closed by a conventional cap I5. Upon the discharge of the extinguisher the powder is pressurized by fiuid from the container H and expelled through an outlet elbow l6 and a dis charge hose i'l through a suitable nozzle (not shown).

Within the filling opening 14 is a shoulder 59 to support an apertured casing adapted to provide a space within the powder charge for the pressure vessel H. Depending from the under surface of the cap I5 is a tubular portion 2i, having a threaded inner surface to receive an apertured insert 22 with a flanged end 24. A puncturing member 25 is adapted to slide within the apertured insert 22 upon pressure being applied to its actuating cap 26. The puncturing member 25 is normally held in an upward position by a spring 21. The lower end of the puncturing member 25 is pointed as indicated at 29 to facilitate rupturing the closure member of the container as will later appear. The cap i5 is made with a conventional handle ring 30 for the easy transportation of the extinguisher and as a handle for screwing and unscrewing the cap during the filling operation.

The stored pressure medium fluid container or pressure vessel l l, in accordance with the invention, comprises a body or container portion 3!, made of any suitable material such as steel to store a fluid medium under high pressure. i'he upper end of the container body is made with a threaded opening 32 in which is secured a closure fitting 34 having a discharge fiuid passage 35 extending therethrough.

As may be seen in Figure 2 the outer end of the fiuid passage 35 is enlarged as indicated at 35 and iormed with an upwardly extending sealing seat 3?. The outer surface of the upper end of the closure fitting 3 1 is threaded as indicated at 39, to receive a cartridge cap member M, apertured at 83 for the discharge of gas therefrom. The cap member it is adapted to engage the flange end 26 of the apertured insert 22 to hold the cartridge in position with its outlet adjacent to the puncturing member 25.

Within the fluid passage 35 of the closure fitting 3 3 is a fiuid fiow li .iiting member or orifice disc The orifice disc may take various forms, as will be hereafter described, each being made with an opening or orifice 2 3, of a predetermined size. Also positioned in the fluid passage 35 and in juxtaposition to the orifice member 62 is a conventional sealing disc adapted to burst under a predetermined pressure within the con tainer H.

The orifice disc 62 and the sealing disc 45 are held in sealing relationship to close the fiuid passage 35 against the sealing seat 3? by a washer 46 secured by a ring nut 47. The ring nut 47 is in threaded engagement with the wall of the enlarged portion 36 of the fiuid passage and is made with at least one vertically extending filling groove 55 spaced around its circumference. In order to secure the nut in position additional vertically extending grooves 50 are made on the inner surface of the ring nut 41 and adapted to be engaged by a suitable tool which may be turned to tighten the ring nut to provide a good seal. In some constructions the washer 46 might be omitted and the sealing discs held in position directly by the end of the ring nut ii. The construction utilizing the washer is advantageous in providing for the production manufacture of the ring nuts by facilitating the making therein of the inner grooves 59.

The fiuid flow limiting member or orifice disc 42, in accordance with the invention, may take any one of the forms shown in section in Figures 3, 5, or 7, depending .upon the requirements of the device with which they are used. In all cases, the fluid flow limiting member is made of a material preferably deformable with respect to that of the sealing disc and the sealing seat 3'1 so that the edge of the limiting means acts as a sealing gasket to prevent the escape of the stored pressure medium.

As shown in Figure '7 the orifice disc 32a is made of a flat piece of material having an opening Ma. in the center thereof and adapted to be positioned against the sealing disc A5 in contact therewith over its entire surface. As shown in Figure 3 the orifice disc 42 has a dished center portion 5! so that its orifice 44 is spaced from the sealing disc 45. In Figure 5 another orifice disc 42b is shown having a dished center portion 5 lb and an orifice opening Mb, further, this embodiment has a reduced center portion 52 about the orifice Mb.

ihe forms of the orifice disc shown in Figures 3, 5 and 7 are particularly suitable for use in an extinguisher such as of the dry powder type, wherein a high rate of discharge is preferable.

The extinguisher ii) is actuated by inverting it and striking its cap 26 against a surface to move the penetrating member 25 inwardly to rupture acegrso the'sealing' disc 45 torelease: the stored fluidpressure medium to expel the fire extinguishing powder. The fluid pressure medium is preferably discharged at a rapid rate and fills the voids between the particles of powder to pressurize the powder and also to cause agitation thereof to loosen the particles so that they may be readily expelled in an even flow. In order to produce the rapid discharge rate the puncturing member 25 is adaptedto extend through both the sealing disc :25 and the orifice opening 44; and by so doing to enlarge the opening 44 to permit the rapid discharge rate of the pressurizing fluid after the puncturing member has been withdrawn. It has been found that the puncturing member 25 read ily pierces the sealing disc 45 to enlarge theopening M without the use of a much greater force than is required to puncture the usual sealing disc 45 and the spring 2'5 withdraws the puncturing member 25 immediately aided probably by the pressure of the released pressure fluid.

In the form of the fluid limiting means shown in Figure 5 the sealing disc 45 and the orifice dis-c 421) are spaced sufficiently to' avoid cutting both members simultaneously and to allow a clearance space for the lips torn in cutting the sealing discs.

The construction shown in Figure-7 is inexpensive to manufacture and is satisfactory in most instances in which the

members

45 and 42a are made of comparatively light material. The construction shown in Figure 5' is advantageous in cases in which the orifice discis made of comparatively heavy material such as for use in units of large diameter. The weakened portion 52 may be formed on either side of the disc 42b about the orifice 46b. While the weakened portion is shown as being formed by making the cross section of the material about the orific thinner than the body of the disc a weakened portion may be made in any other suitable manner such as by scoring the material.

In the event the stored pressure medium fluid container H is subjected to excessive temperatures such as might result in the case of fire resulting in a terrific increase in its internal pressure, the sealing disc 45 is adapted to rupture at a predetermined pressure below the bursting pressure of the walls of the container H. However, by reason of the restriction of the orifice 44 of the fluid flow limiting member 42, the discharge rate of the container H will be at a predetermined safe rate sov that the recoil will not be sufficient to cause the cartridge to rocket and possibly cause damage topersons or property.

In order to facilitate the assembly of a container in accordance with the invention, a unitary pre assembled unit may be'made of the ring nut at, the washer E6, the sealing disc 45,. and the passage restricting means or orifice. disc iii. In this case, the lower end of the ring nut 4? should be made extended and shaped to provide a shoulder to receive the parts which are then secured in position by spinning in extended end it.

In refilling the container I I it is preferred that a new unitary assembly be used in order to assure the orifice member free from dirt, corrosion or the like. The container is refilled by connecting it to a source of fluid pressure with the ring nut ll loosened. A filling passage is thus provided through the vertically extending filling grooves t? across the sealing seat 31 into the interior of the container with only a portion of the incoming fluid passing through the orifice disc. The ring not 6''! is then tightened to seal the container.

A container I! may be provided having a predetermined rate of fluid discharge but which is suitable for use in pressurizing device having various requirements as to the rate of flow of the pressurizing medium. The variation in discharge rate is: accomplishedby providing a variation in the diameter or in the length of travel of the puncturing members 25 or 6?. By this means the size of the orifice 3 5 may be enlarged as desired or, alternatively, no enlargement need be made. Likewise, for devices having a puncturi'ng member of a certain size and/or travel, various pressure vessels or containers I may be provided having any one of the various forms of the fluid flow limiting members 32, a, h or c disclosed, which by reason of their spacing f om the sealing disc 45, may have their orifices 5t, b or c enlarged or not in a predetermined manner diepending upon the form used.

It is thus apparent that the present invention provides a stored fluid pressure medium con tainer overcoming the difliculties and disadvantages of prior devices by providing a container having a limited discharge rate which may be readily charged or recharged. Further, while the container is adapted to be discharged at a safe rate when the disc is ruptured from internal pressure, its construction is such that it may be readily discharged at a fast rate when the disc is ruptured by the usual opening member.

While the invention has been described and illustrated with reference to specific embodiments thereof, it will be understood that other embodiments may be resorted to without departing from the invention. For example, while the orifice has been described, and illustrated as being in the center of the fluid flow restricting memher it is. obvious that it may be located in any part thereof providing a fluid flow. Furthermore, while the invention has been illustrated and described as applicable to a container having a sealing disc closure member, it is apparent that the construction also might be applied to containers havinga seat type closure valve utilizing the herein described construction to provide a limited discharge rate to avoid recoil dificulties. Therefore, the form or the invention set out above should be considered as illustrative and not as limiting the scope of the following claims.

31 claim? 1. A readily chargeable stored. high. pressure medium container for use with a discharge device including a, reeiprocable puncturing menber, the" puncturing member having a predetermined length of stroke and of a predetermined size to" releas fluid at a high rate of discharge under normal operation, outlet means for the container having a threaded inner surface, a closure assembly threadedly engaged in the outlet and including an axially slotted disc nut, means forming a recess in the lower edge of the sealing disc nut, the recess receiving an outer disc and an inner disc, the outer disc imperiorate and at least of a strength to hold the normal pressure in the container, the inner disc positioned between the outer disc and the interior of the container, the inner disc spaced from the outer disc a distance less than the length of travel of the puncturing member so that upon a stroke of the puncturing member both discs are penetrated thereby providing openings therethrough of the predetermined size for the high rate of discharge under normal operation, and means securing the discs in the sealing disc nut providing a unitary assembly therewith retractable for the rapid charging of the container through the axially slotted sealing disc nut.

2. A stored high pressure medium container for use with a discharge device including a reciprocable puncturing member having a predetermined length of stroke and of a predetermined size to release fluid at a high rate of discharge under normal operation, outlet means for the container, closure means for the outlet including an outer imperforate sealing disc at least of a strength to hold the normal pressure in the container, and pressure relief ilow restricting means to release fluid at a low rate of discharge under excessive temperature operation and positioned between outer disc and the interior of the container and including an inner disc, the inner disc spaced from the outer disc a distance less than the length of travel of the puncturing member so that upon a stroke or" the puncturing member both discs are penetrated thereby providing openings therethrough of the predetermined size for the high rate of discharge under normal operation.

3. A stored high pressure medium container for use with a discharge device including a reciprocable puncturing member having a predetermined length of stroke and of a predetermined size to release fluid at a high rate of discharge under normal operation, outlet means for the container, closure means for the outlet includ ing an outer imperforate sealing disc at least of a strength to hold the normal pressure in the container, and pressure relief flow restricting means to release fluid at a low rate of discharge under excessive temperature operation and positioned between the outer disc and the interior of the container and including an inner flat disc having an aperture therein, the inner disc spaced from the outer disc a distance less than the length of travel of the puncturing member so that upon a stroke thereof both discs are penetrated thereby providing openings therethrough of the predetermined size for the high rate of discharge under normal operation.

4. A stored high pressure medium container for use with a discharge device including a reciprccable puncturing member having a predetermined length of stroke and of a predetermined size to release fluid at a high rate of discharge under normal operation, outlet means for the container, closure means for the outlet including an outer imperforate sealing disc at least of a strength to hold the normal pressure in the container, and pressure relief flow restricting means to release fluid at a low rate of discharge under excessive temperature operation and positioned between the outer disc and the interior or" the container and including an inner disc with a dished center portion, the inner disc having an aperture therein, the inner disc spaced from the outer disc a distance less than the length of travel of the puncturing member so that upon a stroke thereof both discs are penetrated thereby providing openings therethrough of the predetermined size for the high rate of discharge under normal operation.

5. A stored high pressure medium container for use with a discharge device including a reciprocable puncturing member having a predetermined length of stroke and of a predetermined size to release fluid at a high rate of discharge under normal operation, outlet means for the container, closure means for the outlet including an outer imperforate sealing disc at least of a strength to hold the normal pressure in the container, and pressure relief flow restricting means to release fluid at a low rate of discharge under excessive temperature operation and positioned between the outer disc and the interior of the container and including an inner disc having a portion of reduced strength for easy penetration by the puncturing member, the inner disc having an aperture therein, the inner disc spaced from the outer disc a distance less than the length of travel of the puncturing member so that upon a stroke thereof both discs are penetrated thereby providing openings therethrough of the predetermined size for the high rate of discharge under normal operation.

6. A stored high pressure medium container for use with a discharge device including a reciprocable puncturing member having a predetermined length of stroke and of a predetermined size to release fluid at a high rate of discharge under normal operation, outlet means for the container, closure means for the outlet including an outer imperforate sealing disc at least of a strength to hold the normal pressure in the container, and pressure relief flow restricting means to release fluid at a low rate of discharge under excessive temperature operation and positioned between the outer disc and the interior of the container and including an inner disc with a dished center portion and the material of at least a part of the dished portion of reduced thickness for easy penetration by the puncturing member, the inner disc spaced from the outer disc a distance less than the length of travel of the puncturing member so that upon a stroke thereof both discs are penetrated thereby providing openings therethrough of the predetermined size for the high rate of discharge under normal operation.

References Cited in the file of this patent UNITED STATES PATENTS Number Name Date 640,207 Korrodi Jan. 2, 1900 1,022,301 Campbell Apr. 2, 1912 2,398,051 Shaw Apr. 9, 1946 2,506,983 Williams May 9, 1950