US2107232A

US2107232A - Sheet metal container

Info

Publication number: US2107232A
Application number: US90808A
Authority: US
Inventors: Blakeway Arthur Henry
Original assignee: Metal Box PLC
Current assignee: Crown Packaging UK Ltd
Priority date: 1935-11-25
Filing date: 1936-07-15
Publication date: 1938-02-01
Anticipated expiration: 1955-02-01

Description

Feb. 1, 1938. A; BLAKEWAY 2,107,232

SHEET METAL CONTAINER Filed July l5, 1936 Patented Feb. 1, 1938 UNITED STATES PATENT oFFlcE Application July 15, 1936, Serial No. 90,808 In Great Britain November 25, 1935 2 Claims.

This invention relates to 'an improved metal container which is particularly adapted for the packaging of liquids. It is customary for such containers, after they are made, to be coated on l the inside with a plastic material, such as paraflin wax which is so composed that it will not flake or craze when the container is stored at a refrigerating temperature or the Walls of the container are accidentally bent or flexed through lil-'contact with each other or with refrigerating coils, ice or the like. y y

In applying the wax coating to the container, it is melted by heat, poured into the container and caused to contact with the entire interior l5 surface thereof. The wax adheres to the metal surface and the surplus wax is drained from the container. The container is then cooled and is -ready for filling.

Since it is customary in the packaging of beer' 0 and similar beverages to pasteurize .the same after theyare in the container, the wax is of such composition that it'will not melt when raised to a temperature at or slightly above the pasteurizing temperature. The composition of the wax,

however, is not a part of the present invention and need not be described here. The object of the present invention is to form the seams of the container and adjacent portions of the body in such a manner as to promotethe preservation of the unbroken surface of the coating under the conditions outlined above, and particularly during the pasteurizing process, when the volume of the liquid and its pressure upon the walls of the container are increased. g5 For this purpose, the side seam of the container is provided contiguous to its outer member with an inwardly extending rib, forming a gully between said rib and the opposed edge of the seam, in which gully an excess of coating material may be trapped to ensure complete coverage of the seam. y

The speciiic construction of the invention in its preferred form, together with its advantages, will be particularly explained in connection with the accompanying drawing, in which,-

Fignre 1 is a side elevation of a portion of a container constructed in accordance with the invention.

Figure 2 is a central sectional view of a portion of the container, showing an inner view of the side 'seam and gully.

Figure 3 is a similar view of the complete container after it is filled and sealed.

Figure 4 is a transverse sectional view of a (Cl. 22o-64) lock side seam constructed according to the invention.

Figure 5 is a similar View of a lap side constructed according to the invention.

As illustrated in Figures 1 to 4, the container 5 in'which the invention is embodied comprises a body portion I made from sheet metal bent into cylindrical form with the meeting edges joined by a lock seam 2.v A bottom end 3 is secured to the body portion I by a double seam I and the top end 5 is secured thereto by a double seam 6.

The top end 5 is represented in the present instance as having a dome 1 with an opening at its upper end, through which the container may be filled or the contents of the container dispensed. The dome 'l is formed with a shoulder 9 termi-n nating in a sealing lip 8, which is adapted to receive a. crown seal II. Within the crown seal II is a gasket I2, preferably of cork, which contacts with the lip 3 to provide anzemcient liermetic seal which can readily be removed by an ordinary cap lifter without in any way injuring the container. f'

The wax coating, which is applied in the manner described above, is indicated at I0, and it will be noted that this coating completely covers the side seam 2 and the double seams Ii and l at the top and bottom of the container. The container may beV filled with the beverage and the seal II applied while the entire surface vof the coating is still in sterile condition.

In the packaging of certain beverages, such as beer for example, it is desirable to pasteurize the same after the container is sealed. In the usual process of pasteurization, the container is passed through a Water bath which is heated sufficiently to raise the temperature of the beverage to approximately 140 F. During this process, the expansion of the liquid imparts a considerable strain to the side seam. It is therefore essential that a good coating of wax be assured along the inside edge of this seam. To this end, an inwardly extending rib I3 is formed in the can body contiguous to the outer member of the side seam 2. This rib extends longitudinally of the seam and forms with the edge of this seam a gully I4, which will trap the coating material during the coating process and assure a full coating along the edge of the seam. The rib I3 preferably extends along the entire length of the seam.

The body of the container may also be provided, contiguous to the inner member of the seam 2, with a bevel I5, which eliminates .the sharp edge that would otherwise be presented Seam by the contiguous outer edge of the seam and also serves the purpose of relieving the strain on the side seam and obviates the tendency oi' the seam and the coating thereon to open as the volume o! the liquid expands during the heating incident to the pasteurizing process. This bevel is formed along the line of greatest potential strain.

In the modlication shown in Figure 5, 2* indicates a lap seam or the lap portion of a lock and lap seam. In this modiilcation, the inwardly extending rib Il is also formed contiguous to the outer member o! the seam 2, and with the edge of the seam forms a gully I4 similar to that shown in Figure 4.

From the foregoing description, it will be seen that both the gully, formed between the rib I 3 and opposed edge of the seam, and the bevel l5, formed by the inner portion of the seam, are important factors in assuring an unbroken interior wax surface not only during the pasteurizing process but also during the subsequent handling oi' the container. Y

While I have shown and described the invention with-reference to a speciilc type of container, it will be understood that this is merely for the purpose of illustration and that both the top and the bottom of the container. aswell-as the manner in which they are secured to the body, and also the construction of the side seam itself, may be modiiled in various ways, without any material departure from the scope of the invention, as defined in the appended claims.

Having thus described the invention. what I claim as new and desire to secure by Letters Patent, is: r

1. A sheet metal container having a coating of protective material applied to the inner surface thereof, said container including a body portion having the side edges joined by a solder bond, the outer member of the side seam being bent inwardly adjacent the side seam and longitudinally of the seam and thence bent gradually outwardly to merge into the peripheral line of the can body whereby sharp edges on the inside of the seam tending to ca use weakness in the protective coating are eliminated and a gully is formed between the inwardly bent portion and the seam, in which gully the coating material may be trapped to assure a good coating of protective material at the edge of the seam.

2. A sheet metal container having a coating of protective material applied to the inner surface thereof, said container including a body portion having the edge portions `ioined by a solder bonded side seam, the body wall carrying the outer member of the side seam being bent inwardly adjacent the side seam and longitudinally of the seam and thence gradually outwardly to merge into the peripheral line of the can body and the body wall carrying the inner member of the side seam being gradually bent outwardly to merge into the peripheral line of the can body whereby sharp edges at the inside of the seam tending to cause weakness in the protective coating are eliminated and a gully is formed between the inwardly. bent portion in the wall carrying the outer member and the edge of the seam, in which gully the coating material may be trapped to assure a good coating of protective material at the edge of the seam.

ARTHUR HENRY BLAKEWAY.