US2381396A

US2381396A - Reinforced container

Info

Publication number: US2381396A
Application number: US515313A
Authority: US
Inventors: Max O Kuhn
Original assignee: Firestone Tire and Rubber Co
Current assignee: Bridgestone Firestone Inc
Priority date: 1943-12-22
Filing date: 1943-12-22
Publication date: 1945-08-07
Anticipated expiration: 1962-08-07

Description

ug. 7, 1945- v M. o. KUHN 2,381,396

REINFORCED CONTAINER Filed Dec. 22, 1943 Patented Aug. 7, 1945 UNITED STATES PATENT OFFICE 2,881,396 REINFORCED CONTAINER Max 0. Kuhn, Cuyahoga Falls, Ohio, asslgnor to The Firestone Tire & Rubber Company, Akron, Ohio, a corporation ,of Ohio Application December 22, 1943, Serial No. 515,313

3 Claims.

This invention relates to containers for the transportation and storage of fluids under high pressure, and more especially it relates to containers of the character mentioned that are reinforced in a manner: that obviates shattering thereof upomrufiture ofs-the walls thereof.

The invention is of primary utility in its application to the oxygen tanks carried by aircraft that are required to ascend to high altitudes, which oxygen is required to sustain life in rarefied atmosphere. In military aircraft subject to gunfire, the puncturing of an oxygen tank is attended with considerable hazard 'due to the expansive force of the released oxygen, which rends the container wall and may impellfragments thereof with great force for a considerable distance. My copending application for Letters Patent, Serial No. 421,307, filed December 2, 1941, now-Patent No. 2,339,554, issued January 18, 1944, discloses broadly a container for fluid under pressure reinforced in a manner to localize a breach in its wall resulting from puncture thereof and to pre-- vent fragmentation, and it is to further improvement of this type of container that this invention primarily is directed.

As previously constructed, the container comprised a hollow, sheet metal cylinder having closed ends of dome or generally hemi-spherical shape. The cylinder was externally reinforced with metal straps that were welded thereto along their respective centerlines, some of said straps extending longitudinally of the container and some extending circumferentially thereof. The latter consisted either of a plurality of individual straps that circumscribed the container, or a single metal strap that was wrapped helicalLv about the container. In either case the circumferential straps did not extend much beyond the medial cylindrical portions of the container. The longitudinally extending straps overlay the circumferential straps and extended onto the end-domes of the container, but did not extend to the axis thereof, being terminated about one half of the distance from the cylindrical portion of the container to the axis of the domes.

It is well known that in containers of theshape described, the stress in the material of the walls resulting from internal fluid pressure is not uniform, but is greater in the circumferential direction than in the longitudinal direction; more specifically the degree of stress in the cylindrical wall of the container is substantially twice as aircraft were equipped with nothing heavier than caliber machine guns. With the advent of 50 caliber machine guns and 20 mm. cannon, the problem of reinforcing the end-domes of the container is presented since the destructive effect of the larger projectiles is much greater. Accordingly one of the objects of this invention is to provide in a simple and efficient manner for the reinforcing of the end-domes of containers of the character mentioned to prevent shattering thereof when penetrated by the larger projectiles mentioned.

Other objects of the invention are to provide improved construction for reinforcing straps of the container to prevent tearing of the container wall against the margins thereof during rending of said wall after being punctured; and toprovide greater safety to the personnel of combat aircraft. Other objects will be manifest as the description proceeds.

Of the accompanying drawing:

Fig. 1 is a side elevation of a reinforced hollow container embodying the invention;

Fig. 2 is an end elevation of the same as viewed from the left thereof; and I Fig. 3 is a section, on a larger scale. on the line 3-3 of'Fig. 1.

Referring to the drawing, especially Figs. 1 and 2 thereof, it will be seen that the improved container comprises a hollow body or shell II that has a central region of cylindrical shape and respective end regions ofhemi-sphericai or dome shape. The shell i0 is composed of sheet metal,

stainless steel being referred because of its durability and strength, but other metals equally'suitable may be employed if desired. The shell per se may be manufactured in any known or pre-- ferred manner, and no novelty therefor isasserte'd herein. One of the end-domes of the shell is axially apertured and provided with a threaded fixture or coupling II by which a suitable pipe or conduit is attached for enabling the container to be charged or discharged.

The shell II is exteriorly reinforced by metal straps that extend circumferentialiy and longi tudinally thereof. The circumferential reinforcement as shown comprises a strap II that extends helically around the shell, the terminal portions of the strap I! being disposed upon the reportion, of the shell. If desired. the single strap It may be replaced by a plurality of individual straps, each extending circumferentially ot the shell with its opposite ends in abutting relation. The strap I8 is transversely flat, and is permanently secured to the shell I. by being electrically welded thereto, the welding being locally effected along the longitudinal centerline of the strap. Reinforcing the opposite end-domes of the shell I. are respective straps it. Each strap ll extends along a meridian line around the dome, about one half of the distance from the axis of the latter to the nearest convolution of the strap ll measured on the surface of the dome. The straps II are flat in transverse section and preferably endless, and are welded to the shell in the same manner as the strap it.

The longitudinal reinforcement of the shell ll comprises a plurality of metal straps II, it. As shown herein, the straps I are six in number, but a greater or fewer number may be employed depending upon the diameter of the container. Preferably each strap It consists of two longitudinal sections, which sections are Joined endto-end by a flat coupling sleeve ii. The straps it overlie the respective convolutions of the strap ll, their end portion extending onto the domeends of the shell and terminating in abutting relation to the near margins of the dome-rings M. The straps it are permanently attached to the shell it .by being electrically welded thereto locally along their respective centerline, as indi-- cated at I9, Fig. 3.

A salient feature of the invention is the novel cross-sectional shape of the straps l8. Whereas similar straps of the oxygen containers heretofore provided were formed with upstanding marginal flanges, the marginal portions of the straps it are bent outwardly and backwardly so that they overlie the body of the strap, in slightly spaced relation thereto, the raw edges of the strap being in confronting relation. The construction is best shown in Fig. 3 wherein the folded marginal portions of a strap it are shown at "a, "a. The arrangement is such that the lateral marginal portions of the strap are rounded on a radius that is greater than the thickness of the metal of which the strap is compoud.

The straps l3, l4 and I8 divide the surface of the container into relatively small areas in which breaches in the container wall, arising from puncture thereof, are localized. Thus when any portion of the container wall is punctured, the pressure of the escaping gaseous fluid enlarges the puncture by rending and tearing the metal in alldirections. When a tear reaches the strap I: or II it doesnot pass the same, but mayfollow the strap due to the shearing action of the raw margin thereof, the action being similar to the tearing of paper along a straight edge pressed thereupon. But tears that intersect the longitudinal straps ll, eitherdirectly or by way of the straps ll, ll do not follow said straps ll. This is because of the rounded or curled lateral margins thereof which enable the ruptured containerwall to bend or fold thereover without tearing, as is indicated in broken lines in Fig. 3.

".lhe invention involves no radical departure from prior construction, yet it achieves the several advantages set out in the foregoing statement of oblccts. By limiting tearing of the container well after puncture, fragmentation thereof is obviated and the hazard to craft and personnel from flying metal is abated. Although the extremities of the container are not as extensively reinforced as the remainder thereof, this is not. of great importance since the stress in the domes oi the container is much less than in its cylindrical portion, and the ends of the container are less exposed to gunfire. The curled edges of the 1 straps l6 not only strengthen them, but also improve the appearance of the container.

Modification may be resorted to without departing from the spirit of the invention or the scope thereof as defined by the appended claims.

What is claimed is:

1. In a container for fluid under pressure, the combination of a hollow metal shell of general cylindrical shape having dome-like hemi-spherical ends, and metal straps secured to the outside of the shell and extending circumferentially and longitudinally of the shell so as to divide the sur face thereof into relatively small areas wherein shattering is localized in case or rupture of the container wall, said straps being welded to the container shell solely along the longitudinal centerlines of the straps and spaced from the lateral margins thereof, the straps extending in one direction at least having their marginal portions folded voutwardly and over the body portion with the respective edges of each strap in confronting relation, to prevent tearing of the container wall along the margins of said folded straps.

2. In a container for fluid under pressure, the combination of a hollow metal shell of general cylindrical shape having dome-like hemispherical ends, and metal straps secured to the outside of the shell and extending cireumferentially and longitudinally or the shell so as to divide the surface thereof into smaller areas wherein shattering is localized in case of rupture of the container wall, said straps being welded to the container solely along their longitudinally centerlines in spaced relation to their lateral margin l portiom, the circumferential straps comprising a strap extending helically about the cylindrical portion of the container and terminating near the respective junctures oi the end domes with the cylindrical portion, and endless straps disposed solely on the end domes and encircling the latter along meridian lines thereon, the longitudinal straps terminating in abutting relation to said dome straps.

3. A combination as defined in claim 2 wherein the longitudinal straps and the endless domestraps have their marginal portions folded out wardly and over the body portion with the respective edges of each strap in confronting relation to prevent tearing of the container wall along the margins of said folded straps.

MAXO. KUHN.