US3127049A

US3127049A - Safety pressure vessel for carbonated beverages and the like

Info

Publication number: US3127049A
Authority: US
Publication date: 1964-03-31
Anticipated expiration: 1981-03-31

Description

March 31, 1964 F. WELTY ETAL 3,127,049

SAFETY PRESSURE VESSEL FOR CARBONATED BEVERAGES AND THE LIKE Filed Sept. 7, 1961 2 Sheets-Sheet l FRANK WELTY RAYMOND o. WELTY FIG. 5

BYMKK ATTOR EY March 31, 1964 WELTY ETAL 3,127,049

SAFE IY PRESSURE VESSEL FOR CARBONATED BEVERAGES AND THE LIKE Filed Sept. 7, 1961 2 Sheets-Sheet 2 INVENTOKS FRANK W ELT Y B RAYMOND o. WELTY 1 a ATTORNEY United States Patent 3,127,049 SAFETY PRESSURE VESSEL FOR CARBONATED BEVERAGES AND THE LIKE Frank Weity, 4962 Lockwood Blvd, and Raymond D. Welty, 4307 Lake Road, both of Youngstown, Ohio Filed Sept. 7, 1961, Ser. No. 136,575 Claims. (Cl. 220-44)) This invention relates to a safety closure cap structure for pressure vessels and more particularly to an improved and simplified arrangement for protecting a pressure-filled vessel against rupture due to excessive pressure. The primary object of the invention is to provide this safety feature on a pressure vessel without adding to the complexity or cost of the vessel, and in accordance with this invention this object is accomplished by so constructing the conventional closure cap structure of the vessel that the cap itself and its sealing means act as the safety valve to relieve the excess pressure.

The invention is specifically intended to protect handlers and/ or users of transportable gas-filled pressure vessels against injury as may result from explosive rupture thereof. In the bulk distribution of beverages, for example, it is now common practice to fill a closed container with a carbonated beverage against a back pressure supplied by a carbonating gas. At the place of consumption the container is connected to a source of carbonating gas under pressure to expel or dispense the beverage to a faucet while maintaining the desired degree of carbonation in the beverage remaining in the container. Normally, this gas source is a high-pressure cylinder filled with compressed gas to which is connected a pressure reducing and regulating valve. If this valve is improperly adjusted or becomes defective, the beverage container may become dangerously subjected to excessive gas pressure with consequent explosive potentialities. It is accordingly highly desirable to provide the container or vessel with a safety valve feature.

Beverage containers of the kind mentioned above are used in large quantities and are often subjected to rough handling. It is therefore desirable that the safety valve feature be imple, inexpensive, and inherently rugged to the extent that it cannot become inoperative because of rough handling. Further, it must be fail-safe in nature and of a character incapable of being tampered with.

This invention meets all the above requirements by so constructing the wide-mouth closure cap assembly universally used on bulk-beverage containers in such manner that the assembly itself inherently operates as a safety valve. First, the design of the sealing ring used and its relation to surfaces of the container and cap is such that unless the cap is fully applied or in full on position it will release the pressure in the container. Secondly, the cap retaining means is provided with a yieldable link or element whereby abnormal pressures acting on the cap will force the cap outwardly a sufiicient distance to release the pressure while yet retaining the cap on the container.

The manner in which the above objects are accomplished by this invention will become apparent upon consideration of the following specification and accompanying drawing wherein there is disclosed preferred embodiments of the invention.

In the drawing:

FIGURE 1 is a vertical section of a safety closure cap assembly constructed in accordance with the teachings of our invention;

FIGURES 2 and 3 are elevational views of a cap securing element used in the assembly of FIGURE 1 before and after the application of excessive pressure to the cap which had been secured thereby;

' ring used in the assembly of FIGURE 1;

FIGURE 5 is an elevation of a modified form of cap securing device which may be used in carrying out the principles of our invention;

FIGURES 6 and 7 are plan views of the container opening and the cap member, respectively of a further embodi ment of the invention; and

FIGURES 8 and 9 are elevation and sectional views, respectively, of the opening neck structure of FIGURE 6.

Referring first to FIGURES 1-5, reference numeral 10 designates a portion of the top wall of the pressure vessel or container to which the invention is applied. When used for beverages, such containers are commonly made of stainless steel and have large openings to facilitate cleaning and inspection of the inner surfaces thereof. Commonly, these openings are formed with an upwardly directed annular projection of a portion of the top wall of the container, such as shown at 11 in the drawing. This annular projection is used to seal and secure a closure cap, with the securing means being of the quick-disconnect type whereby the closure cap may be quickly applied to and removed from the container.

In our construction, the free end portion of the annular projection 11. is flared outwardly as shown at 12 and the closure cap 13 is formed with an integral inwardly opening annular channel 14 which receives the major part of the annular projection 11. The cap member 13 is dieformed from a single disc of stainless steel and, as shown in FIGURE 1, the annular channel aforementioned provides a cylindrical wall 15 radially inward of and concentric with the flaring 12. The channel also provides an end wall 16 which spans the annular space between the wall 15 and the flaring 12.

To effect a fluid-tight seal between the side wall 11 forming the opening into the container and the closure cap 13 we provide an annular resilient and deformable sealing ring 17 which may be molded from neoprene rubber. As shown in FIGURES 1 and 4, the ring 17 is generally U-shaped in cross section to provide concentric radially inner and outer bands integraliy connected by a body portion 18. In use, the outer band of ring 17 overlies the inner surface of flaring 12 in depending relation while the inner band of the ring overlies the cylindrical wall 15 of the cap member 13 with the body portion 18 of the ring resting against the inner surface of the annular end wall 16 of the cap member. To provide sensitivity in the sealing action the body portion 18 of ring 1'7 is formed with a continuous rib 19 on its top surface and for this same purpose as well as for an additional purpose to be explained below the free edges of the concentric bands of the ring are outwardly beaded as shown at 20. It should be apparent that with the sealing ring 17 installed in the manner shown in FIGURE 1 and with the cap tightly applied to the annular projection 11 whereby the sealing ring is compressed, a continuous effective seal is formed between the flaring 12 and the cap member to prevent the escape of fluid, either gas or liquid, from the container.

To provide the quick-detachable interconnection between the cap and the projection 11 and to provide means for tightening the cap onto the projection, we provide a series of circumferentially spaced cams on the outer surface of the projection 11 for engagement by lugs extending inwardly from the outer cylindrical wall of the cap member 13. As indicated in FIGURE 1 these lugs may be simply inwardly bent portions of this outer cylindrical wall, as shown at 21. In the form of the invention shown in FIGURES 1-3, the cams are formed from strips of metal 22 which are suitably contoured or bent to fit snugly around the curvature of the outer surface of projection 11. Strips 22 are formed at one end with an inte gral tab 23 which is rigidly welded to the metal of wall 11 and the other end of each strip is bent downwardly as shown at 24 and this other end portion is also rigidly welded to the wall 11. Each of the strips 22 is formed with an entering portion 25 of substantial length and of generally horizontal disposition which terminates in a steep cam portion 26. The steep cam portions 26 are provided to insure that the sealing ring 17 will be compressed a predetermined amount sufficient to insure the required sealing action. The steep cam portions 26 terminate in elongated slightly-inclined terminal portions 27 by which the final tightening of the cap member is accomplished and by which the cap member is held against accidental rotation in an off direction. The latter characteristic results from the flatness of the portions 27 and resultant friction as will be understood.

In accordance with the principles of our invention,

portions

23, 24 and 25 of the strips 22 may be rigidly and continuously welded to the metal of projection 11 but

portions

26 and 27 are either not welded or are only lightly welded at spaced points so that these portions may bend upwardly upon the application of excessive internal pressure acting on the cap member. What extent of these

portions

26 and 27 is left unattached will, of course, be determined by the thickness and strength of the strips 22, the number of strips used, the diameter of the cap, and the maximum pressure desired in the container.

Referring again to the sealing ring and its manner of use, it will be obvious that so long as the cap member is tightly applied to the container the configuration of the ring provides a self-sealing elfect so that any pressure Within the capacity of the container may be retained. However, if the cap rises with respect to the container the ring will open up to the shape shown in FIGURE 4 whereby only a line contact will remain between the flaring 12 and the ring. This line contact results from the head 20 on the outer band of the ring, and the bead has the further function of limiting the further radially outward expansion or diameter growth of this line contact. At this point high pressure cannot be retained and any abnormal pressures applied to the container will be bled off. However, the bead does provide a sensitive seal so that upon release of this excess pressure and the resultant lowering or tightening of the cap by the spring action of the strips 22 will re-establish the seal and prevent spoilage of the beverage or other contents of the container.

In the embodiment of the invention shown in FIG- URE 5, the cams are provided by radially outward flanges of a ring 28 which is welded or otherwise suitably secured to the neck of projection 11 of the container 10. To provide the safety feature involved herein either the ring itself may be slit or deeply scored at locations indicated by the doted line 29 in FIGURE or by slitting or scoring the flanges themselves at similar locations. The operation of this embodiment is precisely the same as that described above in connection with FIGURES 1-4.

In the embodiment of the invention illustrated in FIGURES 6-9 the cap-locking cams are integrally formed of the sheet metal of the container by providing excess metal outwardly of the flare 12', which excess metal is rolled downwardly to form a skirt indicated generally by reference numeral 30. This exces metal or skirt is notched at circumferentially spaced points as shown at 31 to allow vertical passage of the lugs 21' of the closure cap. It should be understood that the closure cap of FIGURE 7 is substantially identical with the cap of FIGURE 1, and that the same sealing ring as shown in FIGURES 1 and 4 will be used in the embodiment of FIGURES 69.

Skirt 30 is die-cut to provide three circumferentially spaced cams each consisting of a flat entering portion 32, a steep intermediate portion 33, a slightly inclined locking portion 34, and a stop 35. 'Cam portions 33 insure that the sealing ring will be properly compressed before the lugs 21' enter onto the slightly inclined locking portions 34. They have the further function, which is also true of the first described embodiments, of retaining the cap against being blown upward at time of removal by any residual gas pressure which may be in the container. By allowing the lugs 21 to raise a substantial distance to the entry portions 32, the sealing ring is fully released to allow the instantaneous release of any such residual pressure. Thus, even though the cap be removed quickly with a continuous rotating motion, the upward force on the cap will be dissipated before the lugs 21 run off the entry end of cam portions 32.

In the embodiments of the invention shown in FIG- URES 6 thru 9, the gauge of the metal of the container is such that upon the appearance of dangerously high pressure in the container the skirt 30 will be deformed to release this high pressure. Such deformation will comprise the rocking inward of portions of the skirt (or cams) and the flare 12 adjacent the points of contact of the lugs 21 with the skirt. This causes the flare 12' to bow outwardly in the regions of the slots 31 and thereby the flare is made out-of-round and entirely incapable of maintaining a seal with the sealing ring. In actual practice, the gauge of the metal used is determined by test. The deformation under high pressures is rather severe in the embodiment in FIGURES 6-9, and it is not intended that these deformed containers will be reused.

It should now be apparent that we have provided an improved safety pressure vessel for containing and dispensing carbonated beverages and the like which accomplishes the objects initially set out. By providing for the limited yet retained outward movement of the normally required closure cap for such vessels or containers and so constructing the sealing ring as to relieve the excessive pressure upon such limited outward movement of the cap, we are able to provide the saefty valve feature without adding components or increasing the cost of the vessel or container. Further, the nature of this safety feature is such that it cannot be tampered with and is extremely rugged and durable to withstand the severe conditions of handling service to which this type of equipment is normally subjected.

It will be readily apparent to those skilled in the art that specific means, other than those herein disclosed, may be employed to allow the pressure cap to have a limited outward yet definitely retained outward movement to relieve excess pressure in the container. For example, the flanges forming the lock-on cams engaged by the lugs of the cap and of the general style used in the first described embodiments may be made of suitable material and dimension to be deformable and thus themselves serve as the yieldable means allowing the cap to have limited outward movement.

Since changes may be made in the details of the essential components of the safety closure cap structure herein disclosed without departing of the spirit and scope of the invention, reference should be had to the appended claims in determining the scope of the invention.

We claim:

1. A safety cap structure for a pressure vessel having a wide-mouthed opening defined by an annular projection of its wall and in which the free end portion of said projection is flared outwardly to provide an internal conical sealing surface comprising a flanged disc-like cap adapted to be received over said outwardly flared end of said annular projection with the flange thereof concentric with and radially outward of said annular projection, said cap having an inner annular sealing surface concentric with but radially inward of said conical sealing surface, a plurality of circumferentially extending and circumferentially spaced lugs carried by said annular projection and positioned on the outside thereof between the outer end of the flared portion thereof and the body of said container; each of said lugs having a flat portion extending generally parallel with the said end of said flared portion of said projection, an intermediate portion inclined steeply toward the body portion of said container, and an end portion slightly inclined toward said body portion of the container, a sealing ring which is of inverted U-shape in radial crosssection having side wall portions lying against said conical and annular sealing surfaces, the flange on said cap having radially inward directed detents to engage underneath said lugs and to compress said sealing ring upon rotation of said cap on said annular projection in one direction and the consequent movement of the cap toward the body portion of said container, the arrangement being such that said sealing ring is ineffectual when said detents are under the flat portions of said lugs but is operative to effect a self-sealing action when said detents are under the slightly inclined end portions of said lugs when said slightly inclinded portions are in their normal positions with respect to said conical sealing surface, and said slightly inclined portions of said lugs being yieldable in an outward direction parallel With the axis of said annular projection where-by upon the appearance of excessive pressure within the container said cap can lift off slightly to render said sealing ring ineffectual and thus permit the release of excess pressure in said container.

2. Structure according to claim 1 further characterized in that said cap has a cylindrieally-shaped Wall radially inward of said flared portion and an annular end wall in the end projection of said flared portion to provide an additional bearing for said sealing ring.

3. Structure according to claim 1 further characterized in that the free edges of the side walls of said ring are each formed with a continuous integral bead having normal continuous contact with said annular and conical surfaces, said beads having only line contact with said annular and conical surfaces when said cap is moved to outward yet retained position by excessive pressure in said vessel which line contact is insufiicient to retain said pressure, and said beads also acting to limit the change in diameters of said free edges of said side walls.

4. Structure according to claim 1 further characterized in that said lugs each comprises an elongated metal strip curved about said projection, said metal strips being solidly secured to said projection only at spaced points along each strip to allow said slightly inclined portions of the lugs to be bent out of position upon the application of excessive vessel pressure to said cap.

5. Structure according to claim 1 further characterized in that said conical sealing surface on said projection is provided by said outwardly flaring portion of said projection and in that said lugs depend integrally from a skirt formed integrally with and rolled over from the outer edge of said flaring portion.

References Cited in the file of this patent UNITED STATES PATENTS 2,266,314 Eshbaugh Dec. 16, 1941 2,513,458 Dion July 4, 1950 2,549,387 Richeson Apr. 17, 1951 2,948,431 Kuhn Aug. 9, 1960 3,042,246 Welty et al July 3, 1962

Claims

1. A SAFETY CAP STRUCTURE FOR A PRESSURE VESSEL HAVING A WIDE-MOUTHED OPENING DEFINED BY AN ANNULAR PROJECTION OF ITS WALL AND IN WHICH THE FREE END PORTION OF SAID PROJECTION IS FLARED OUTWARDLY TO PROVIDE AN INTERNAL CONICAL SEALING SURFACE COMPRISING A FLANGED DISC-LIKE CAP ADAPTED TO BE RECEIVED OVER SAID OUTWARDLY FLARED END OF SAID ANNULAR PROJECTION WITH THE FLANGE THEREOF CONCENTRIC WITH AND RADIALLY OUTWARD OF SAID ANNULAR PROJECTION, SAID CAP HAVING AN INNER ANNULAR SEALING SURFACE CONCENTRIC WITH BUT RADIALLY INWARD OF SAID CONICAL SEALING SURFACE, A PLURALITY OF CIRCUMFERENTIALLY EXTENDING AND CIRCUMFERENTIALLY SPACED LUGS CARRIED BY SAID ANNULAR PROJECTION AND POSITIONED ON THE OUTSIDE THEREOF BETWEEN THE OUTER END OF THE FLARED PORTION THEREOF AND THE BODY OF SAID CONTAINER; EACH OF SAID LUGS HAVING A FLAT PORTION EXTENDING GENERALLY PARALLEL WITH THE SAID END OF SAID FLARED PORTION OF SAID PROJECTION, AN INTERMEDIATE PORTION INCLINED STEEPLY TOWARD THE BODY PORTION OF SAID CONTAINER, AND AN END PORTION SLIGHTLY INCLINED TOWARD SAID BODY PORTION OF THE CONTAINER, A SEALING RING WHICH IS OF INVERTED U-SHAPE IN RADIAL CROSSSECTION HAVING SIDE WALL PORTIONS LYING AGAINST SAID CONICAL AND ANNULAR SEALING SURFACES, THE FLANGE ON SAID CAP HAVING RADIALLY INWARD DIRECTED DETENTS TO ENGAGE UNDERNEATH SAID LUGS AND TO COMPRESS SAID SEALING RING UPON ROTATION OF SAID CAP ON SAID ANNULAR PROJECTION IN ONE DIRECTION AND THE CONSEQUENT MOVEMENT OF THE CAP TOWARD THE BODY PORTION OF SAID CONTAINER, THE ARRANGEMENT BEING SUCH THAT SAID SEALING RING IS INEFFECTUAL WHEN SAID DETENTS ARE UNDER THE FLAT PORTIONS OF SAID LUGS BUT IS OPERATIVE TO EFFECT A SELF-SEALING ACTION WHEN SAID DETENTS ARE UNDER THE SLIGHTLY INCLINED END PORTIONS OF SAID LUGS WHEN SAID SLIGHTLY INCLINED PORTIONS ARE IN THEIR NORMAL POSITIONS WITH RESPECT TO SAID CONICAL SEALING SURFACE, AND SAID SLIGHTLY INCLINED PORTIONS OF SAID LUGS BEING YIELDABLE IN AN OUTWARD DIRECTION PARALLEL WITH THE AXIS OF SAID ANNULAR PROJECTION WHEREBY UPON THE APPEARANCE OF EXCESSIVE PRESSURE WITHIN THE CONTAINER SAID CAP CAN LIFT OFF SLIGHTLY TO RENDER SAID SEALING RING INEFFECTUAL AND THUS PERMIT THE RELEASE OF EXCESS PRESSURE IN SAID CONTAINER.