IL30633A - Container closure - Google Patents

Description

Container closure ALUMINUM COMPANY OF AMERICA U.S. 6¾.,109 A container and closure assembly, and particularly an assembly including a closure having preformed means to be engaged, without the use of rolling tools, with retaining formations on the container.

The combination of containers and closures are known in which a sheet metal closure is reformed to engage retaining means on the container by means of rolling tools which bear upon and reform the metal against the container formations. Pilferproof package closures, separable by fracture occurring when the package is opened to provide a removable reclosure portion and a retained band, have been made with the threads or other retaining means on -the re-closure portion preformed, but rolling tools still were required to conform the band to a container shoulder after the closure was in place thereon.

Aside from the matter of expense of the rolling tools, their use presents a problem when the' container is made of plastic material, since plastic containers, when made in economical thicknesses, are not strong enough to withstand the pressure of such rolling tools. Moreover, containers with handles projecting near the neck are increasing in use, and these projections obstruct the operation of the usual rolling tools.

In accordance with the pre&©nt- invention, there is rovided a container-closure assembl com risin a con- tainer formed with a neck having a sealing surface and an upper portion and a metal closure around the neck including a sealing surface Rearing on said container sealing surface and a skirt portion having an upper portion cooperating with the upper portion- of the neck to seal the container, there being: (a) radially extending lugs circumferentially spaced apart on the neck of the container below said upper portion and which have downwardly sloping upper camming surfaces and lower surfaces disposed at an angle of not over 90° from a subtended vertical line, and (b) a lower portion on the skirt of the closure terminating in an inwardly and upwardly turned edge underlying the lugs on the neck when the sealing surfaces of the container and closure are in sealing contact.

The invention will now be described in greater detail with reference to the accompanying drawings, in which: Fig. 1 is an elevational view of a plastic container with the neck of plastic material formed according to the invention; '■ Pig. 2 is an enlarged top plan view of the container; Fig. 3 is a vertical cross-sectional view of a closure for application to the container of Figs. 1 and 2; Fig. I. is a vertical sectional view through the neck of the container of Fig. 2 and the closure of Fig. 3 with the closure partially applied; .

Fig. 5 is a vertical sectlc-ial view through the neck o the container of Fig. 2 and the closure of Fi . 3 and showing a later stage in the application of the closure; Pig. 6 is a view similar to Fig. 5 but showing the closure fully> applied; Fig. 7 is a cross-sectional view showing a package with a modified form of the container and closure including a sealing gasket and a tear-off closure; and Fig. 8 is a cross-sectional view showing an adaptation of the invention to a glass container.

Referring to the drawings, the plastic container 10 shown in Figs. 1 and 2 has a handle 11 and a neck 12.

Surrounding the neck opening is a sealing surface 13 and the neck is threaded exteriorly at ll above a shoulder 15 · Projecting from this shoulder are two diametrically opposed lugs 16 and immediately below the shoulder are two lugs 17 of greater radial projection than, and centered on the diameter normal to the center diameter of, the lugs 16. These lower lugs 17 have sloping upper faces 18 and lower faces 19 which preferably are substantially flat but may be disposed at an upward inward angle. As shown, the outer edge of each of the lugs 16 and 17 extends between about I4.O0 and about 50° on a circumscribing line.

The closure 20 has a top panel 21 and a skirt 22 which is pre threaded at 23 to mate with the thread ll and has a shoulder 2I. betwee the threaded part 23 and the lower wider skirt portion 2 » The skirt is weakened on a circumferential line by slits 26 between bridges 27· The edge of the skirt. is turned inwardly and upwardly at 28 to leave an edge 29 facing upwardly. The skirt portion below the weakened lint? -ccriprises a looking band 30.

When the closure is screwed onto the container, the lower skirt portion has sufficient resilience to pass over the lugs 16 with very little skirt distortion. However, the lower skirt portion can pass over the lugs 17 only by reason of substantial temporary distortion induced by the camming surfaces l8, the lower skirt portion changing substantially from round toward oval, as it passes over the maximum diameter of these lugs, so that the turned edge snaps into place thereunder. The container neck and closure may be designed to leave a minimum space between the skirt edge 29 and the lug faces 19· When the closure is removed, the edge 29 bears on the lug faces 19 and may penetrate the plastic material slightly. In any case, the faces 19 provide no outward camming action and the edge will not pass over the lugs. Accordingly, the bridges 27 are fractured by continued unscrewing of the closure and the portion 30 remains on the bottle.

In removal, the unrestrained portion of the skirt edge between parts bearing on faces 19 bows upwardly, resulting in uneven tension on the bridges. In the structure disclosed, any tendency of the edge to bow upwardly is limited by the lugs.16 against which the edge 29 will bear in the event of such bowing. This as'sures satisfactory fracture of the bridges.

The camming lugs 17 may also be three or more in number and the distortion of the cap skirt shape will be toward triangular, square, hexagonal, etc. as dictated by the number and disposition' of the lugs 17. The lugs 16 preferably are equal in . irmer to the lugs 17, but a structure with four lugs 17 and two lugs 16, with all six lugs equally spaced clrcumferentlally and the lugs 16 diametrically disposed would be within the structure of the invention. In this case the skirt distortion would be rectangular. The circumferential spacing of the lugs always is such that the camming action of any one lug will be opposed by similar action of at least one other lug.

The present invention is not limited to a pre-threaded closure . The upper skirt portion may be plain and may be reformed to match any retaining means provided on the container neck.

Once the bridges are broken the threaded portion of the closure can be used repeatedly as a reclosure while the band 30, remaining on the container, shows that the package has been opened. < The bearing of the top panel 21 of the closure on the sealing surface 13 of plastic material usually provides an efficient seal, but some packages may require a gasket for proper sealing. This is particularly true with friction closures in which the skirt has no retaining means above the upturned edge. Pig. 7 shows a container and cooperating friction closure embodying the invention. The container has the lugs 17 and an inwardly disposed flange 31 and the closure has a frangible top panel I4.I the upturned edge 29 on its skirt and contains a gasket 3 having a central recess 33 characterized by a downwardly flaring outer wall 3 and a depressed diaphragm 35· With this construction, any internal pressure on the diaphragm will tighten the bearing of the wall 31}- on the lower edge of the flange 31» assuring sealing contacts ■ .

The lugs and upturned edge cooperate most efficient- ly when the lugs are of plastic material. Pig. 8 shows an adaptation of the invention to provide the same advantage for a glass container. A plastic collar 36, having the lugs 16 and 17 is placed in a groove 37 of the glass container 38· The lugs then function as described above.

Claims (6)

WHAT WE CLAIM IS:

1. A container-closure assembly comprising a container having a neck which has an upper sealing surface, an exterior screw thread formation below said sealing surface and outwardly extending lugs of plastics material below said sealing surface , said lugs having downwardly sloping outer surfaces and substantially outwardly radiating lowtr surfaces and being spaced circumfere tially for providing opposed cam surfaces below said upper sealing surface, and a metal closure comprising a top panel and a resiliently distortable skirt portion having a threaded portion to engage the screws thread formation on said neck and an inwardly disposed and. upwardly directed bottom edge separated from said threaded portion by a circumferential weakened fracture line and underlying said lower surfaces of said container lubs, said lugs being slightly penetrable by the upwardly directed edge of said skirt portion and restraining said edge from being drawn outwardly and up- wardly over said lugs.

2. A container-closure assembly according to Claim 1, in which the lower surfaces on said container lugs are disposed to form an outwardly open included angle of not over 90° with a depending vertical line.

3. · A conta ner-closure assembly according to Claim l.or Claim 2, in which said container neck is provided with additional lugs of less radial extent than said first-named lugs and having their lower surfaces disposed above the lower surfaces of said first-named lugs.' " ■ . ·...,*..-.

4. A metal closure adapted for application to a container neck which has an upper sealing surface, an exterior screw thread formation below said sealing surface and outwardly extending lugs of plastics material below said sealing surace, said lugs having downwardly sloping outer surfaces and substantially outwardly radiating lower surfaces and being spaced "circumferentially on said neck to provide opposed cam surfaces thereon, said metal closure comprising a top panel and a resiliently distortable skirt having a threaded portion . to engage the screw thread formation on said neck and an inwardly disposed and upwardly directed bottom edge separated from said threaded portion by a circumferential weakened fracture line, said closure skirt having a transverse diameter at said upwardly directed edge adapted to pass over container lugs having a greate transverse diameter at the. outer surface of said, lugs upon resilient distortion of said closure skirt 1 so that, upon application of the closure to the container, said upwardly directed edge underlies said lugs on said container neck.

5. · A container-closure assembly substantially as hereinbefore described with reference to Figures 1 to 6 or Figure—-~ ?~vf the accompanying drawings. '■■'<■■

6. A metal closure adapted for application to a container neck which has an upper sealing surface, substantially as hereinbefore described with reference to Figure 3 of the accompanying drawings. For the Applicants