US2068384A - Insulated container - Google Patents

Description

Jan. 19, 1937.

C. L. NEWPORT ET AL INSULATED CONTAINER Filed Sept. 25, 1955 T L I). LNmN W IQNVENTORS.

Patented jan. 19, 1937 UNITED STATES IINSULATED CONTAINER Charles L.

Newport and Herbert G. Smith,

Los Angeles, Calif.

Application September 23, 1935, Serial No. 41,688

5 Claims. (01. 62-915) The present invention relates to insulation for articles desired to be kept at some given temperature, and while the invention has wide application, it is particularly directed to a container or sack of high insulating value to hold dry ice and an article or container to be kept cold, such as a container of ice cream.

Another object of the invention is to provide a highly efilcient insulating container which is low in first cost so that a merchant can supply them gratis, even for use once only.

Combined flexibility and durability is an object of this invention to provide an all-enveloping container which will conform to the shape of the contents both initially as well as subsequently when the ice has partially Sublimated.

Simplicity of, and low cost for manufacture is still another object of this invention including provision for the use of an odorless inorganic insulating material which, by the method of manufacture, is readily and thoroughly sealed with a jacket.

Obviously, the ideal insulated container is one of double wall construction in which there is only insulation between the walls and no connecting members for the rapid transfer of heat. Accordingly, this invention seeks to provide a construction whereby all walls are formed integrally from a single sheet of thin flexible material, such as paper, although other and rigid materials may be used within the scope of this invention; the outer walls being fully separated from the inner end of the finished container where there is a rim connecting inner and. outer walls integrally to seal the spaces between the walls.

Another and important object of this invention is to provide a container of this class in which the peculiarly advantageous insulating value of carbon-dioxide vapor is used to advantage, along with the sensible cooling effect of the vapor. We are aware that the vapor from dry ice has been used direct for its insulating value, but, in a flexible or deformable, or other than rigid 5' container, definite gas passages are not assured between the article and the container. In this invention the gas is caused to travel through the insulation proper in a manner to not only reduce the influx of heat, but to additionally increase the insulating value of the insulating material by the presence of vapor in the intersticial spaces to reduce heat conducting eddies as well as to reduce the air content and the hygroscopic quality peculiar to all otherwise high grade fibrous or finely divided insulating material.

We have illustrated by the accompanying drawing, one practical embodiment of our invention and one practical method for the manufacture of same.

In the said drawing:

Figure 1 is a view in vertical section of a container holding a carton and dry ice; the view showing the container just before the upper ends are folded over the carton and suitably sealed for transportation.

Figure 2 is a diagram showing the first steps in the method of manufacture.

Figure 3 is a similar diagram showing subsequent steps.

Figure 4 is a small scale view in elevation of a modified form of container.

The container shown in Figure 1 comprises a suitably flexible but otherwise substantially selfsupporting form of insulating material 6, formed with an annular wall 6a and an integral bottom wall 6b. While any suitable material may be employed, we find that rock wool has many advantages for this purpose and particularly since it is entirely contained within a flexible jacket.

The jacket comprises the outside bottom wall I; the inside bottom wall 8 spaced from wall I by the bottom wall 6b of the container; the outside wall 9 co-extensive of the outer surface of wall 6a; and the inner wall ill coextensive of the inner surface of wall 6a; the walls being all formed from a single blank of such material as paper, which also forms the annular rim ll connecting the outer Wall 9 and the inner wall III at their upper extremities.

The container is shown as holding a cake I2 of dry ice between its bottom wall and a contained carton l3. While there may be other ice placed around the sides of the carton, and the container is suitably flexible or oversize to receive it, the view shows only the cake at the bottom to emphasize the high insulating quality of the product. The inside wall near the bottom is provided with vapor outlets l5 while the outer wall is provided with similar outlets at the top as at it. Thus the cold vapor from the ice will rise upwardly through the insulating material, displacing air and tending to keep same dry and reducing the conductivity as a whole. It is to be noted that meanwhile the flow of gas is in a generally outward direction through the material, counter-current to the normal influx of heat. This has the peculiar property of absorbing the heat as it tries to move inwardly and thus the function of the insulation and vapor combined is to prevent heat from reaching the interior, whereas the common use for dry ice results in it actually increasing flow of heat through insulation, this larger amount of heat then being absorbed by the ice which must be well distributed over the entire surface of the article being preserved. Now of course this invention applies as well to the old method, but, it has in mind to change the general concept of the use of this product by using its own vapor to prevent influx of heat and to then readily absorb the decreased amount of heat before it reaches the article being preserved.

In Figure 2 is shown a mandrel l8 about which both the paper and the insulating material, in sheet form, are wrapped. The mandrel atone end is fitted with a sleeve or tube l9. This tube is suitably rigid and preferably made of thin metal; it being employed temporarily as a form in which the inside annular paper wall of the product is formed. The walls, hereinbefore described, are indicated in this figure on the corresponding portions-of the corresponding material. The insulating material is co-extensive of the tube while the paper is continued far beyond the tube and sufliciently over the other end of the mandrel that it is there free to'be folded over as shown to form what becomes the bottom inside Wall of the jacket. Any methods known to the manufacturer of paper products and containers may be employed, as are well understood. However, we have shown the said folded-in end of the paper as sealed and cemented or glued by a paper disc or sticker indicated at 20.

Now by withdrawing the mandrel from the tube, the suction effect thereof will tend to introvert the extending paper by drawing the bottom wall down toward position, within the -tube l9. Now a slightly smaller mandrel l8a is inserted into the tube with the paper then between the said mandrel and the tube. This irons out creases in the paper especially if the said mandrel is rotated while being inserted. The outer end of the tube prevents the paper from being introverted beyond the proper degree. Now the tube is withdrawn, from the lower end of the product before the bottom walls thereof are shaped; the tube having served its purpose as a form for the inner annular paper wall.

With the new mandrel in place as shown in Figure 3, all parts are finished except the bottom wall to be formed by the insulation and the outside bottom wall to be formed by the paper. Next the paper to form the inside bottom wall is flattened against the corresponding end of the mandrel while at the same time the insulating material overlapping this end of the mandrel, as shown, is turned over against the end of the mandrel. It will be understood that rock wool, for example, in this form is readily shaped and packed so that it will make a substantially homogeneous bottom wall. Next the paper to form the bottom outside, is folded down against the corresponding insulating material and firmly secured as by the disc 2|, or otherwise.

The finished product, partially as the result of the properties. of the insulation, and partially by reason of the disposition of the paper, is suitably self-sustaining in its shape while being very readily deformed at the upper ends so that insulating effect may be distributed over the top of the contents as well by folding in the upper edges and suitably securing them. It will be understood that a lightweight and tough but flexible paper is to be preferred for the jacket and within the skill of those familiar with such arts, it may be previously seamed, pressed, scored, creped or otherwise treated to readily adapt itself to change in shape. However the method described is simple and permits of using unprepared paper.

Various changes in design, construction and manufacture will suggest themselves to the minds of those skilled in the art and such changes will be within the scope of this invention claimed hereinafter.

In Figure 4, we have shown a method for em ploying the product of this invention to enclose a carton or otherarticle as for long periods of preservation or for transportation over long distances or through the mails. This consists of employing two containers such as those described, end to end, and these ends are joined as by a strip of gummed paper 22. At each end of the contained carton is provided the ice cake l2, so that in this case flow of gas would be from each end of the double container toward the center.

We claim:

1. In a container of the class described, a flexible jacket comprising; an outside bottom wall, an inside bottom wall of smaller diameter spaced above the outside bottom wall, an outer wall extending vertically from said outside bottom wall to the top of the container and there turning to form an annular rim, and an inside annular wall depending from said rim and parallelling said outside annular wall and connecting with said bottom wall; all being integrally formed from a sheet of flexible material, and flexible insulating material filling all spaces between said walls, said materials co-operating to form a self-supporting open top container.

2. The container as in claim 1; there being gas inlets formed in the inside annular wall of the jacket near the bottom and gas outlets formed in the outer annular wall of the jacket near the top.

3. In a container of the class described, a paper tube closed at each end, insulation co-extensive of the inner surfaces of said tube for approximately one-half the length thereof and also coextensive of one closed end of said tube; the uninsulated part of said tube being introverted with respect to the insulated part to form inside walls co-extensive of said insulation.

4. In a container of the class described, a container shell comprising a vertical annular wall and a bottom wall integrally formed of flexible fibrous insulating material, and a. flexible jacket completely enclosing said material and co-extensive of all surfaces thereof; there being gas inlets formed in the inside wall of said jacket near the bottom and gas outlets formed in the outside wall of said jacket near the top.

5. In a container of the class described, a container body comprising a vertical annular wall and a bottom wall integrally formed of flexible fibrous material, and a flexible all-enveloping paper jacket co-extensive of all surfaces of said material; there being gas inlets. formed in the inside wall of said jacket near the bottom and gas outlets formed in the outside wall of said jacket near the top.

CHARLES L. NEWPORT. HERBERT C. SMITH.

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