US2439366A

US2439366A - Self-sealing container

Info

Publication number: US2439366A
Application number: US380259A
Authority: US
Inventors: Mclaughlin Leone
Original assignee: Wingfoot Corp
Current assignee: Wingfoot Corp
Priority date: 1941-02-24
Filing date: 1941-02-24
Publication date: 1948-04-06
Anticipated expiration: 1965-04-06

Description

April 6, 1948. L'. MCLAUGHLIN 2,439,366

SELF-SEALING CONTAINER Filed Feb. 24, 1941 Patented Apr. 6, 1948 2,439,366 SELF-SEALING CONTAINER Leone McLaughlin,

Akron, Ohio, assignor to Wingi'oot Corporation, Akron, Ohio, a corporation of Delaware Application February 24, 1941, Serial No. 380,259 4 Claims. (Cl. 1543.5)

This invention relates to improvements in the i construction of containers adapted to hold liquids and, more particularly, to self-sealing fuel tanks for airplanes and the like.

In the construction of fuel airplanes, it is impossible to make the tanks sufficiently strong to resist the penetration of bullets due to the necessity for avoiding any increase in weight of the plane, as far as possible;` Therefore, these fuel tanks have been constructed so as to permit the projectile to pass through the `walls of the tank, and then seal the hole after puncture. This is effected by incorporating in the walls of the tank certain self-sealing materials, such as rubber, which are soft enough to flow or which swell upon contact with the gasoline or oil in the tank, the effect in either case being to close the hole promptly and prevent the escape. of the fluid. These self-sealing materials necessarily have little strength, since they mu'st be soft and capable of swelling in the gasoline or other hydrocarbon contained in the tank and it is, therefore.

`necessary to` support the self-sealing material with layers or plies of stronger materials.

In the selection of materials having the desired strength, it is needful, not only that the liner in which they are incorporated have the requisite strength in the unpunctured condition, but also that it retain its strengh in large partafter being pierced a number of times in service. The severest test of a. tank takes place at the point of exit of a bullet or other projectile since the penetration 'at the point of entrance and the-passage through the liquid in the tank often cause the bullet te yew rvr-tumble before it exits. As th-n result, the bullet may rip through the wall of the tank, as it leaves, broadside or at an angle.- This causes a relativelylarge jagged hole and may remove the support for the self-sealing layer at that point. The weight of the fluid in the tank and the surges set up by the passage of the bullet therethrough may then force the soft material into the opening and maintain lthe bullet hole in a distended condition, thus preventing sailing.

tanks for military v uncured rubber or partially cured 4 where the bullet rips through the fabric crosswise, since then a large number of threads are cut. The result is that the bullet hole may still remain distended in this now unsupported region and fuel will be lost, causing the return of the plane to its base or a forced landing.

In order to overcome this defect of liners incorporating cross-woven fabric, the present in vention contemplates the use of cord fabric in place o f lsuch crosswoven fabric. Cord fabric.

as is well known, consists essentially of warp threads or cords only, no weft threads being present or, if present, being few and weak. Such weft threads, if present, are intended only to hold the cords together until the fabric has been frictioned lor otherwise treated with an adhesive material which takes over the function of holding the cords in place. I'he function of the weft threads having been places along their length in order that they may not crimp the cords or This is particularly true of tank linings made.

up of `a layer of partially cured rubber or like .hold liquids.

chafe the same at their points of contact. Hence, for the purposes of this invention, a weftless fabric `and a broken-weft fabric are considered to be equivalents since in each case the weft threads do not function in the finished article.

One obect of the invention is to provide an lmproved liner for self-sealing tanks adapted to Another object of the invention is to provide a liner for airplane fuel tanks of improved self-sealing characteristics. Other objects will in part be obvious andwill in part be pointed out hereinafter. I

The invention will be described in connection with the accompanying drawings, wherein one form of the invention has been shown merely by way of illustration and wherein:

Figline 1 is a plan view of a liner embodying the invention with portions of the various plies and layers broken away. and

made up of several layers and plies of material.

completed, they are often broken at a number of 'stantially unsupported at 2,4easee a layer of semi-cured rubber i, approximately v IA" in thickness. Another this time with the cords running horizontally and hence at an intermediate angle to the cords in each of the plies 3 and 4. separates the sealing layer 5 from another layer of partially cured rubber 1. This in turn is covered with a plyA 8 of fabric which has been coated with neoprene (polymerized chloro butadiene) or othersynthetf ic rubber resistant to gasoline and hydrocarbons generally.

When a bullet pierces a lining having the foregoing structure, it may be positioned with its longitudinal axis at right angles to the cords of ply 3, for example,l in which event it will break a maximum number of cords in this ply. Were this the only reinforcement for the sealing layer 5 or were additional plies disposed with their cords running parallel to those in ply 3, it will be Y obvious that a large hole would be left in the liner and the soft rubber layer 5 would be subthis point. This condition is prevented, however, by the disposition 'of the

plies

4 and 6. Since the cords in ply l are disposed at cross angles to the cords in ply 3, a bullet cutting the maximum number of cords in ply 3 will cut a minimum number of cords in ply 4 since the bullets longitudinal axis will be parallel to the cords in this second ply. Likewise, a bullet in a position to break the largest number of cords in plies 3 and l taken together, will break a minimum number of cords in ply 6. As a consequence. Ione ply or the other will suffer a minimum amount'of breakage and will continue to function as a support for one or the other of the sealing layers i and 1. Sealing of the bullet hole ply of cord fabric 6,'

at any point throughout the thickness of the liner will, of course, stop the escape of fluid from the tank.

While the invention has been described in connection with one specific embodiment thereof, it .will be understood that various combinations of fabric plies and sealing layers may be effected, all without departing from the scope of the invention. Thus, in its simplest form, the improved liner may consist of one layer of not more than are few and weak, or that in which the weft threads have been broken, leaving only the warp threads in functioning condition. By omitting the weft threads, it is possible to have more warp threads in a given space since they Amay be'placed closelyl parallel to each other in the fabric and thus greater strength is secured. Also, omission of the weft threads somewhat decreases the thick'- ness of the ply and hence the thickness of the liner, space and weight being a consideration in all airplane construction. The fabricvplieswill be placed with the cords of each at angles to the cords of the others, preferably at cross angles. Where more than two plies arepresent, the maximum possible angles between the cords of each ply and those of the others will be maintained. The fabric plies may be placed on either side of the sealing layer or two plies may be bonded topartially cured rubber, by which is intended to include uncompounded uncured rubber as well tion, it will ordinarily be desirable to face the liner on the inside with a ply of neoprene-coated fabric or fabric coated with some other material which is resistant to attack by the gasoline, since otherwise rubber would be dissolved andV would contaminate the fuel or lubricating oil. This ply may be cross-woven if desired. 0n the outer side of the liner, additional strength-giving materials may be present, such as plywood or Plioform, cyclized rubber, serving to maintain the contour of the exible hner. The whole may be enclosed in a metal casing or, preferably, will be placed in the wing of an airplane where the walls of the wing and bulkheads will serve to support the tank.

While there has been described above one prefered vembodiment of the invention, it will be apparent that the same may be modified in various respects, as indicated, or in any other feasible manner. It is intended, then, that the patent shall cover, by suitable expression in the appended claims, all features of patentable novelty residing in the invention. v

I claim:

1. A liner for self-sealing containers adapted to hold liquid hydrocarbons comprising a layer of partially cured rubber, two plies of weftless or broken-weft fabric with the warp threads of` each at cross angles to those of the other bonded together and to one side of said rubber layer, a third ply of weftless or broken-weft fabric bonded to the other side of said rubber layer with the warp threads at an intermediate angle to the warp threads of the other two plies and a ply of polymerized chlorobutadiene coated fabric bonded to said third fabric ply.

2. A liner for self-sealing containers adapted to hold liquid hydrocarbons comprising at least two layers of rubber capable of swelling in a hydrocarbon and at least two plies of weftless or browen-weft fabric interleaved with said rubber layers and bonded thereto with the warp threads of each ply at an angle to those in each of the said liner.

4. A compact liner for self-sealing containers adapted to hold hydrocarbon liquids consisting of not more than several layers of hydrocarbon-sensitive rubber adapted on contact with a liquid 'hydrocarbon to quickly seal a rupture of the liner, a plurality of fabric plies in supporting relation with a sealing layer, at least one of said plies being disposed face to face with said sealing layer and another said ply being face to face with one of said sealingv layer and said first. ply, said respective plies comprising weftless or broken-weft cord fabric arranged with the cords of the respective plies extendingat a substantial so that less cords will orin one ply than in another' ply when the liner is ruptured. and an inner facing on the liner of hydrocarbon resistant material adapted to protect the hydrocarbon-sensitive layer against exposure to a hydrocarbon until rupture occurs.

LEONE McLAUGHLIN.

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

angle to each other dinarily be severed Number 6 UNITED `STA'I'ES PATENTS Name Date Landis Oct. 12, 1915 Denman Jan. 2. 1917 Ericsson June 14, 1921` Privett May 1, 1923 Hopkinson Feb. 28, 1928 Gray et al Dec. 21, 1937 FOREIGN PATENTS Country Date Number 301.089

Great Britain Sept. 26, 1929