US2210225A - Can - Google Patents

Description

g 6, 1940- M. D. M. WALENSKY 2,2 ,225

CAN

Filed May 3, 1938 Patented Aug. 6, 1940 um l-io- STATES CAN Marjorie Dorothy Mabel Walensky,

London,

England, assignor to Easycantop Limited, London, England, a company of Great Britain Application May 3, 1938, Serial No. 205,783 In Great Britain May '24, 1937;.

2 Claim-SQ (Cl. 220-48) This invention relates to cans or like containers, more particularly the sealing lid or end closure or closures thereof.

The invention has reference to cans or like containers having a recessed end closure provided with a scoring or weakeninggroove, usually circular, through which a piercing tool is to be thrust and levered about the rim of the can to shear the closure along the scoring to' open the can.

In practice, the shear frequently fails to follow the scoring, and the lid or end closure either buckles or shears across its face and sometimes bends about the piercing instrument, so preventing a clean opening being formed in the lid or end closure.

The principal object of the present invention is to constrain the shear to follow the scoring, and thereby to ensure effective opening of the can. Other objects will appear as the description proceeds.

According to the present invention, the portion of the closure to be removed has a foldable border advantageously a grooved border of undulous con- 1 formation adapted to fold concertina fashion under an applied lateral pressure, the border being so formed and arranged in relation to the outer rim of the can that when a piercing instrument is thrust through the scoring and levered about said rim as a fulcrum, it exerts a lateral pressure on the border so causing said border to fold and present a progressively increasing resistance to shearing otherwise than along the scoring, whereby shearing is constrained to take place along the scoring and permit the separated portion to be levered out by the piercing instrument.

Under these conditions, the section of the lid or end closure, bounded by the scoring, can be removed in toto, and a clean opening in said lid or end closure is obtained.

The scoring can be formed in the bottom of the groove or one of the grooves of the grooved border, in which case for the piercing instrument, thus avoiding 'or reducing the risk of slipping of the instrument during piercing.

The scoring and the grooved border maybe circular and where more than one circular groove is provided in the border, they are concentrically v arranged.

Alternatively, the scoring and groove'or grooves of the border may be of other forms than ,circular, more particularly in the case ofcontainers such as oilcans, for example, where only a small said groove acts as a guide section of the lid or end closure is required to be removed to provide a pouring opening.

The end closure, scored and provided with a grooved border according to the invention, serves also to relieve the stresses to which the container is subjected, particularly at the rim, during heating and other processes adopted in the canning industry, since the formation of the grooved border allows of expansion and contraction of the lid or end closure. Moreover, the relief by the groove'or grooves in the border of the stress on the scoring, enables the scoring to bemade deeper and consequently weaker, so enhancing shearingalong the scoring by the piercing instrument. A scoring and grooved border according to the invention can be provided in the top and bottom closures.

A furtheradvantage presented by the invention is that sharp bends are not resorted to in the formation of the groove or grooves of the border, and consequently damage to the tinning, lacquer or other coating employed in manufacture is avoided.- Thus, a valuable assurance against deterioration of thecontents of the tin by corrosion, which occurs where the coating is removed or damaged, is secured. I

The folding together of the walls of the groove or grooves of the border by the piercing instrument is enhanced when the angle at which the instrument bears on the Wall of the groove approaches the vertical.

If the piercing instrument slants too much in relation to'the wall of the groove, it will tend to raise and so flatten out the groove instead of pressing the walls together.

Accordingly, when the scoring is formed at the bottom of a groove, such groove should be arranged close to the outer edge of the closure near the rim of the container, to ensure that the piercing instrument, when thrust through the scoring'and bearing'against the rim of the container as the fulcrum, approaches the vertical.

Similarly, when the scoring is not formed in the bottom of the groove, it should be arranged close to the outer edge of the closure, near to the rim of the container and the groove, or, where more than one is provided, the outermost groove should be arranged closely adjacent to the scoring. I

The groove or grooves of the border form a reinforcement against shearing across that portion of the end closure which is to be removed, and such reinforcement increases progressively in strength as the walls of the groove'or grooves are folded together during levering of the piercing instrument.

The walls of the groove or grooves of the border may extend below or above the face of the end closure.

Several embodiments of end closures according to the invention, applied to a cylindrical can, are illustrated diagrammatically by the accompanying drawing, in which:

Figure 1 is a sectional elevation of an enlarged scale showing part of the upper end of the container. and one form of grooved end closure, broken away, applied thereto, with a piercing instrument thrust through the scoring.

Figure 2 is a view corresponding to'Figure 1, but showing the grooves levered into the closed condition by the piercing tool.

Figure 3 is a top plan view corresponding to Figure 1.

Figure 4 is a view corresponding to Figure l, but with a different arrangement of the scoring.

Figures 5, 6 and 7 are similar views to Figure 1 showing modified forms of the end closure, and

Figure 8 is a top plan view of a closure which provides for the removal of a small portion only, to obtain a pouring opening.

In the drawing, I designates a cylindrical container and 2 a recessed lid or end closure applied to the container to seal it.

- In the embodiments illustrated, the edge of the end closure or lid is folded about the outer rim of the can, so reinforcing said outer rim.

Also in these embodiments, the lid 2 is formed with two concentric grooves 3 and 4 near to the rim of the container. The outer groove 3 may be deeper than the inner groove 4, or in other words, the grooves may be said to decrease progressively in depth as they recede from the outer rim of the can.

The lid 2 is provided with a scoring or weakening groove along which the lid is to be sheared to open the container.

The scoring 5 is arrangedin concentric relation to the grooves 3 and 4 and, except in Figure 4, is situated between the outer groove -3 and the rim of the container I.

In Figure 4, the scoring 5 is formed in the bottom of the outer groove 3.

The walls of the grooves 3, 4 advantageously converge and are rounded at the bends and at the junction of the meeting walls, so that an undulous border comprising contiguous corrugations or dales alternating with a hill is presented. By rounding the bends, cracking of the tinning or other covering is avoided. The depth of the grooves and the width at their mouths are such that their walls will fold together when subjected to moderate lateral pressure.

In Figures 1, 2 and 4, the junction between the walls i and 8 of the grooves extends above the flat faces 9 and iii of the lid, while in Figure 5, it is substantially flush with said faces.

In Figure 6, the inner portion ill of the lid is domed, and the junction between the walls I and 8 of the grooves 3, 4 extends above the fiat outer face 9 in which the scoring 5 is formed.

In Figure '7, an upstanding reinforcing rib ll bounds the grooves 3 and 4 and the inner portion II] of the lid is raised above the outer flat portion 9.

In opening the can, a piercing instrument l2, as illustrated diagrammatically in Figure 1, is thrust through the scoring 5 and is then levered against the rim of the can as a fulcrum.

The lower end of the instrument is thus forced against the wall 6 of the outer groove 3 and presses it inwards towards the wall I which, in turn, is pressed on to the wall 8 of the inner groove, as shown in Figure 2.

In this way, a reinforcement which builds up in strength is obtained as levering proceeds, and a progressively increasing resistance is offered to shearing across the lid, so that shearing is constrained to take place along thescoring 5 and a clean removal of the lid along the scoring results.

The provision of the grooves 3 and 4 presents also the advantage that they render the lid capable of expansion and contraction and so reduce the stresses to which the ordinary closure is subjected during heat and other treatment adopted in the canning industry.

By providing an upstanding rib as in Figure 7, reinforcement is secured directly levering by the piercing instrument is commenced, should the walls of the grooves 3, 4 beweak.

, The section of the lid to be removed may be of other shapes than circular and may be only a comparatively small section.

Thus, for example, as illustrated by Figure 8, the section it] to be removed may be elliptical in shape and of less than half the full area of the lid, so as to provide, when removed, a pouring opening for the container content, which may be oil, for example.

The grooves need not necessarily be continuous. They may take the form of circular arcs spaced around the lid.

The invention is applicable to cans of other shapes than cylindrical, for example, cans of square, oblong or elliptical cross section.

Also, one groove only can be provided, but it will be found that more than one groove ensures the most effective results.

Both the bottom and top ends of the can may be formed with a scoring and grooves, as described, if desired.

By variation in the distribution of the grooves, their depth and their width, and the degree of inclination of their walls, and by differing combinations of the grooves above and below the level of the surface of the lid or closure, and variation in relative step formation or gradation in height and depth of successive grooves, and by changes in level of the part bounded by the groove or grooves, for instance, by making it flat, domed, concave or other shape, a large number of variations in appearance of the lid or closure can be obtained without departing from the invention.

In opening the can, the piercing tool can be thrust through the scoring at several points along it and levered about the outer rim.

I claim:

1. A can having an end closure, a reinforced outer rim projecting beyond said. end closure, and forming the sole rim both for said can and said end closure, said end closure being made of thin sheet metal and having a scoring which extends adjacent to said reinforced outer rim and defines a section of said end closure to be removed for opening the can, and an undulous border pressed from said section to be removed, said border comprising symmetrical undulations reversing in curvature alternately, with their walls widely spaced to produce partial reinforcement, while retaining flexibility of said closure, and by their thinness and configuration being foldable under lateral pressure of a piercing instrument thrust through the scoring and levered about said reinforced outer rim, whereby to augment the reinforcement of said border at the point of entry of said piercing tool by producing by the fold a.

thickened edge on the border at said point, which thickened edge prevents shearing across and buckling of said section to be removed and constrains the shear to take place along the scoring as Levering of said piercing. instrument proceeds, so that the section thereby separatedv can be levered out by said piercing instrument.

2'. A can according to the previous claim 1, having said symmetrical undulations on said border, decreasing in depth successively in a direction from said reinforced outer rim of the can towards the middle of the closure, for the purpose of facilitating further the fol walls of said undulations in opening the can by said piercing instrument.

I MARJORIE DOROTHY MABEL WALENSKY.

'ng together of the 5

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