US2204831A - Closure - Google Patents

Description

June 18, 1940. H. w. SNODGRASS cnosuma Filed larch 2, 193a Patented June 18, 1940 {UNITED STATES TENT QFFlCE CLOSURE HenryW; Snodgrass, Lancaster, Pagassignor to Armstrong Cork v(lump-any, Lancaster, Pa., a

corporation of Pennsylvania v v 7 Application March 2, 1938,, Serial No. 193,404

' Claims. (01115-43) Myiinvention relates to closures and more particularly to the so-called double shell closures which: generally comprise an inner cap provided with means for removably securing the closure to a receptacle, such asscrew thread formations, andan outer shell telescoped overthe inner .cap andsecured thereto and serving to;conceal the thread or other formations when the closure is in sealing position on a receptacle. One of the major problems in the manufacture of closures ofthis type is to prevent relative rotation between the innercap and the outer shell caused by the turn--.

ing stress required to remove the closure from the receptacle it seals. This turning stress is often greatly augmented by poorly formed threads on the receptacle or by reason of adhesion of the closure and the receptacle caused by seepage of the. contents of the receptacle ,or, corrosion of the metal parts. 1 1

An object of my invention is to provide a sim-, ple and effective union between the inner cap and,

the outer shell whereby relative rotationis prevented and to provide a .union which may be effected by the simple expedient of deforming the. skirt of the outer shell, preferably by the formation of a bead upon-the exposed end thereof.

In my preferred embodiment, the inner cap is provided with a radial flange extending substantially normal to the cap axis and having extended surface areas lying in a plurality of planes, with adjacent areas joined at a relatively sharp angle I so as to provide an abutment between adjacent surfaces. Some or all of the surfaces may be of arcuate contour to provide cam surfaces which upon association with the bead of the outer shell prevent relative movement between the parts, since any movement in either a clockwise or counter-clockwise direction will cause the component parts to more firmly interengage, the cap being normally rotatable only in a single plane.

My invention is illustrated in the attached drawing, in which Figure 1 is an exploded view partly in elevation and partly in section illustrating an outer shell and an inner screw threaded cap prior to assembly into a double shell closure;

Figure 2 is a sectional view of an assembled closure embodying my invention;

Figure 3 is a similar view illustrating a modiiication; and

Figure 4 is a broken plan view of a modified type of flange for the inner cap structure.

Referring first to Figure l, the outer shell comprises a top portion 2 and a skirt 3. The inner cap is formed with a top 4 and a skirt 5; the

length of theskirt 3, being slightly greater than theskirt 5, provides an extended portion for subsequent deformation toeffect interlocking of the cap and shell upon assembly. The skirt 5 is provided with screw thread formations 6 although other types of securing means may be employed and the cap may assume various forms depending. upon the size and type of container to be sealed.

- The skirt 5 is provided with a flange 1 which, in the embodiment illustrated, extends radially from the skirt of the cap and lies substantially normal to the axis of the cap. The surface of the flange l is deformed to provide extended surface areas lying in a plurality of planes.

In the embodiment illustrated in Figure 1, lands 8 and Q are provided, each of which extends in a different plane. These lands 8 and 9 are alternated about the surface of the flange 1 and it has been found that six lands are satisfactory for a 28 mm. screw cap. It is desirable to provide surfaces of extended area so that the outer shell when deformed by engagement with the flange 1 mayreadily follow the contour thereof, thusassuring a positive locking engagement of the shell with the cap. It is also desirable to connect the adjacent flange areas. lying in different planes at a relatively sharp angle to provide abutments such as illustrated at I!) and H in Figure 1 which limit relative movement.

Referring now to Figure 2 which clearly shows the interlocking of the component parts, it will be observed that the cap has been telescoped within the outer shell and that the projecting portion of the skirt 3 is formed into an inwardly, upwardly and outwardly extending bead l2 which is deformed about the flange I so that portions l3 of the bead lie in engagement with the lands 8 and are provided with abutments l4 and I5 lying in engagement with the corresponding abutments l0 and l I of the flange 1. It will be further noted that portions I6 of the bead ii. are of arcuate formation corresponding to the arcuate portions 9 of the flange l and thus may be defined as being in substantially the same plane. The bead I2 closely follows the contour of the flange 1 throughout its entire area, due largely to the fact that the deforming surfaces 8 and 9 are all of relatively extensive surface area.

In my preferred closure, the flange 1 terminates in a cut surface I6, and the outer diameter of the flange I is preferably slightly greater than the inner diameter of the skirt 3, say .002" on a 28 mm. cap, thus causing the cut surface C of the flange l to engage the inner surface I! of the skirt 3 enhancing the interlocking engagement of the cap and shell. In Figure 3, the flange 1 is not trimmed to a true circumference and the irregular edge portion is formed into an axially extending flange l8 which, upon assembly, lies parallel to the skirt of the outer shell and is held firmly thereagainst by the cut edge IQ of the bead l2. In this embodiment of my invention, the surfaces 20 and 2| of the bead l2, and their corresponding lands lie in parallel planes normal to the axis of the cap, whereas in the embodiment of Figure 1, the lands 9 are of arcuate formation.

Figure 4 illustrates a modified flange constructiton in which the flange 22 is undulatory and provided with undulations 23. In this structure the flange is directed outwardly and downwardly from the skirt 24 at an angle of approximately 45. The undulations provide a plurality of arcuate surfaces similar to those designated by the numeral 9 in Figure 1 and serve to prevent relative rotation of the members. The surfaces 23 act as cams always tending to enhance the engagement of the deformed portion of the outer shell therewith regardless of the direction of rotation.

In the fabrication of closures embodying my invention, the inner shell is telescoped within the outer shell and a curling tool is applied to the "skirt of the outer shell to deform the same and "urge it into engagement with the surface of the locking flange. Thus, the assembly of the inner cap and the outer shell into locking engagement is simple, rapid and inexpensive. Obviously, the interlocking may be accomplished by means other than the specific bead structure illustrated.

While I have described and illustrated certain preferred embodiments of my invention, it will be understood that the invention may be otherwise embodied and practiced within the scope of the following claims.

I claim:

1. A double shell closure comprising an outer shell and an inner cap telescoped one within the other in substantially axial alignment, an outwardly extending flange on the cap, said flange having its outwardly extending surface disposed as a plurality of extended surface areas lying in a plurality of planes, the outer shell interengaging with a plurality of said extended surface areas and locking said cap and shell against relative rotation.

2. A double shell closure in accordance with claim 1 in which at least some of the extended surface areas on the outwardly extending flange are of arcuate contour with respect to a plane normal to the longitudinal axis of the cap and in which portions of the outer shell lie in face to face engagement therewith to lock the component parts against relative rotation.

3. A double shell closure in accordance with claim 1 in which the flange terminates in a cut edge penetrating the material of the skirt of the outer shell and is held in such position by portions of the outer shell lying in planes substantially corresponding to the planes of the extended surface areas of the flange.

4. A double shell closure comprising an inner cap having a skirt provided with means for removably securing the closure to a receptacle, an outwardly extending flange on the skirt of the cap, said flange lying substantially normal to the axis of the cap, certain portions of the flange of extended surface area being deformed and out of the plane of other portions of the flange, said portions being connected at a relatively abrupt angle whereby a substantially axially extending abutment is formed between areas in one plane and areas in another plane, an outer shell telescoped over the inner cap, the skirt of the shell being deformed about and cooperating with the flange to prevent relative rotation of the cap and shell.

5. A double shell closure comprising an inner cap having a skirt provided with means for removably securing the closure to a receptacle, an outwardly extending flange on the skirt of the cap, said flange having extended surface areas lying in a plurality of planes, an outer shell teler scoped over the inner cap, the skirt of the outer shell being formed into an inwardly, upwardly and outwardly extending bead, the outwardly extending portion of said bead lying in substantially the same planes as the planes of the surface of the flange on the inner cap.

HENRY W. SNODGRASS.

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