US1861570A - Metal can and closure therefor - Google Patents

Description

June 7, 1932. A. G. HOPKINS METAL CAN AND CLOSURE THEREFOR Filed Nov. 25, 1930 Patented June 7, 1932 UNITED STATES PATENT caries ARTHUR G. HOPKINS, OF MASPETH,

PORATION, OF NEW YORK, N. Y.

METAL CAN AND CLOSURE THEREFOR Application filed November 25, 1930.

This invention relates to metal cans and to closures therefor, and more particularly to such cans and closures intended to form an air-tight metal container.

Metal cans are ordinarily provided with an opening through which the can may be filled or emptied, and with a plug or closure adapted to be forced into the opening. When the cans are first filled at the factory, it is customary to apply the closure by striking the same with a mallet. This frequently forces the closure into the can opening at a slant, due either to the closure having been initially positioned out of level, or due to its being struck at an angle. This results in a line contact, instead of a surface contact, which reduces the efi'ectiveness of the seal between the can and its cover, and, furthermore, mutilates or deforms the can opening, which prevents the obtaining of the desired tight sealing fit.

Even if the insert or closure has been initially hammered into place correctly, the can opening is apt to be deformed out of round when the can is opened, particularly if the screw driver or similar implement used to open the can is worked mostly at one side of the cover. This, again, will prevent accurate fit between the closure and can when the can is re-sealed.

And if the can is first sealed properly, and then opened carefully and evenly all around the periphery of the closure, the can opening may yet be deformed when the can is resealed, by forcing the closure into the can opening at a slant. The condition, may, of course, be aggravated by the occurrence of two or more of the above factors, for the can opening or/and cover may be deformed in any one direction at one time, and thereafter be deformed in another direction at another time, so that a line contact, rather than a surface contact, is at best obtainable, and in extreme cases there may be no contact at all at a portion of the periphery of the can opening. 7

With the general object in View, of obviating all of the foregoing difliculties and of facilitating the closing, opening, and re-sealing of the can, I have heretofore devised a Serial No. 498,006.

novel closure for such a can, the side wall of which is stepped so as to form a straight centering portion which is dimensioned to readily fit the can opening, a transition portion, and a straight sealing portion which is dimensioned for a force or friction fit with the can opening. This prior invention is disclosed in detail in my copending application Ser. N 0. 490,111 filed October 21, 1930.

The object of the present invention, generally speaking, is to improve the metal can disclosed in my aforesaid copending application. More specifically, it is an object of the present invention to so combine the can and closure that the desired accurate force or friction fit between the can and closure will exist near the bottom of the closure, at which point it is relatively rigid and certain to retain its shape. Another object is to obtain the desired force or friction contact near the bottomof the depending flange of the can opening, at which point the flange is most resilient and capable of a snug fit even after the can has been opened and closed a considerable number of times. A still further object of the present invention is to so relate the can and closure that the closure may be of standard or conventional type, making it readily interchangeable with the closures of other cans of similar dimension, and readily replaceable if lost.

To accomplish the foregoing objects, I provide the can with a cover seat having a downwardly depending flange defining a can opening, but the said flange instead of being straight, is provided with a straight centering portion dimensioned to readily fit the closure, a preferably tapered transition portion, and a straight sealing portion which is dimensioned for a force or friction fit with the closure. The latter may then be provided with a straight side wall, and in all respects may be of perfectly conventional type. With this construction, all of the advantages of my prior construction are retained, andv at the same time additional advantages are obtained because any deformation of the closure due to opening the same with a screw driver or the like, takes place at the upper part, rather than the lower part thereof. The lower portion of the closure is rigid and holds its shape accurately, and a snug fit therewith by the can opening is insured, because the depending flange wall of the latter is mostly resilient at the lowermost portion thereof.

To the accomplishment of the foregoing and such other objects as will hereinafter appear, my invention consists in the metal can elements and their relation one to the other as hereinafter are more particularly described in the specification and sought tov be defined in the claims. The specification is accompanied by a drawing in which:

Fig. 1 is an elevation taken in section through a metal can embodying the features of my invention;

Fig. 2 is a section through the upper por tion of the can, showing the closure in place preparatory to being forced home; and

Fig. 3 is a section similar to Fig. 2, but showing the closure forced home.

Referring to the drawing, the body of the metal can may be of conventional type, comprising a side wall 12, and abottom. wall 14 which is applied thereto and sealed in any desired manner, as by soldering the seam 16. The can further comprises a cover seat 18 applied to the opposite end of the side wall 12, and also sealed thereto in any desired manner, as by soldering the joint 20.

The cover seat 18 is provided with a downwardly extending or depending flange which defines the can opening, but this flange instead of being straight, is designed to fit and cooperate with the can plug or closure 22 in a novel manner. The closure 22 may be of conventional type, including the usual annular flange 2a and depressed central portion 26 joined by a straight side wall 28.

The depending flange of the cover seat 18 is stepped into a plurality of portions of dif ferent dimension, and more particularly, is provided with a straight centering portion 30 which is dimensioned to readily fit or freely receive the closure 22, and a straight sealing portion 32 which is dimensioned for a force or friction fit with the closure 22, and these straight portions are preferably joined by a transition portion 34 which may be tapered in the manner shown. The lower edge of the straight portion 32 may be rolled to form a head 36 which strengthens and increases the resilience of the straight portion 32 of the flange. It may be mentioned that the stepping or change in diameter of the side wall of the closure indicated in the drawing, is somewhat exaggerated for the sake of clarity, and that in actual practice the difference in dimension is rather slight, the centering portion 30 being designed to receive the closure accurately although without a friction or force fit, while the sealing portion is smaller by only that slight amount needed to obtain the desired friction or force fit.

In operation the filled cans may be capped accurately in a facile and rapid manner, because the closure 22 may be preliminarily seated in the can opening without resistance, and rests upon the transition portion 34 in the manner shown in Fig. 2. In this position the closure centers itself and assumes the desired horizontal position. When the cover is forced home in the manner shown in Fig. 3, it remains in true alignment with the can opening, first, because it is initially seated properly, second, because it is guided by the centering portion 30 of the can openin and, third, because the additional distance which it must be driven is only a fraction of the total ieight of the side wall of the closure.

While the invention is applicable to metal cans intended for any use, it 1s particularly useful in connection with cans carrying paints or other liqulds or sollds necessltating a perfectly air-tight closure. In the case of such cans, it is essential to avoid deformation of the closure or/and can opening when first closing the can, and also when opening or closing the can at subsequent times. With the present can deformation is avoided when closing the can, because of the factors outlined in the preceding paragraph. Deformation is further avoided when opening the can because even if the closure is pried open entirely at one side thereof, no appreciable mutilation takes place because the closure, after reaching only a slight tilt, comes to the enlarged or centering portion 30 of the can opening, at which point the closure is freed from the can.

The accuracy of the mating walls of the can and closure is further preserved, because the friction walls are located at the bottom of the closure and can opening. It will be evident that the side wall 28 of the closure is most rigid and most capable of retaining its original shape at the lower portion thereof, where it is stayed by the bottom wall 26. Furthermore, in prying theclosure open with a screw driver or similar tool, the upper portion of the side wall 28 may be deformed, but this deformation does not reach down to the lower portion of the side wall 28. With respect to the depending flange wall of the cover seat 18, it will be readily understood that the lower portion thereof is quite resilient relative to the upper portion thereof, and in the present structure this portion is the effective sealing portion. The resiliency of the sealing portion 32 insures a snug fit with the closure, even after the can has been opened and closed a considerable number of times. It may also be observed that locating the sealing portion of the can at the bottom of the closure is particularly convenient when deal-- ing with liquids such as paint. because the paint is kept in contact with only the bottom of the closure, which avoids that inconvenience and sloppiness which result when the side wall of the closure is coated with paint.

Another advantage of the present form of my invention resides in the fact that the closure 22 may be of perfectly conventional type and therefore is interchangeable with other closures of like size, and if lost may be readily replaced.

When the can is intended to be used as an air-tight package, the can opening and closure are preferably, though not necessarily, made circular, so that the side wall 28 of the closure is cylindrical, as well as the centering and sealing portions 30 and 32 of the can opening, while the transition portion 34: may be appropriately rounded, tapered, or conical.

The use of the stepped straight portions employed in my invention should not be confused with the use of a tapered wall, because a tapered wall will result in only a line contact, rather than a surface contact; a tapered wall will not insure horizontal seating of the closure, and is very apt to cause the latter to be seated and subsequently driven home at a slant; and a particularly poor fit is apt to result when the can is closed several times, because in each case the cover may be forced home at a different slant.

It is thought that the manner of constructing and using my invention, and the many advantages thereof, will be apparent from the foregoing detailed description thereof. It will be apparent that while I have shown and described my invention in the preferred form, many changes and modifications may be made in the structure disclosed, without departing from the spirit of the invention, defined in the following claims.

I claim:

1. A can comprising a flange defining a can opening for cooperation with a straightwalled plug or closure, said flange having at its upper end a straight centering portion of large dimension to readily receive said closure, and having at its lower end a straight sealing portion of small dimension for receiving said closure with a force or friction fit, and having a transition portion interconnecting the upper and lower portions.

2. A can comprising a cover seat including a downwardly depending flange defining a can opening for cooperation with a plug or closure, said flange having a straight centering portion dimensioned to readily fit said closure, a transition portion, and a straight sealing friction fit with said closure.

3. A can comprising a cover seat including a downwardly depending flange defining a circular can opening for cooperation with a cylindrical plug or closure, said flange having a cylindrical centering portion dimensioned to readily fit said closure, a transition portion, and a cylindrical sealing portion dimensioned for a force or friction fit with said closure.

portion dimensioned for a force or 4. An air-tight metal package comprising a can including a flange defining the can opening, and an internal plug or closure therefor including a straight side wall, said flange having at its upper end a straight centering portion dimensioned to readily fit the side wall of the closure, and having at its lower end a straight sealing portion dimensioned for a force or friction fit with the side wall of the closure, and having a transition portion interconnecting the upper and lower portions.

5. An air-tight metal package comprising a can including a cover seat having a downwardly depending flange defining the can opening, and a closure therefor including a flange, a depressed central portion, and a straight side wall, said downwardly depending flange having a straight centering portion dimensioned to readily fit the side wall of the closure, a transition portion, and a straight sealing portion dimensioned for a force or friction fit with the side wall of the closure.

6. An air-tight metal package comprising a can including a cover seat having a downwardly depending flange defining the can opening, and a closure therefor including an annular flange, a depressed central portion, and a cylindrical side wall, said downwardly depending flange having a cylindrical centering portion dimensioned to readily fit the side wall of the closure, 2. transition portion, and a cylindrical sealing portion dimensioned for a force or friction fit with the side wall of the closure.

Signed at New York in the county of New York and State of New York this 21st day of November A. D. 1930.

ARTHUR G. HOPKINS.

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