CLOSURE CAP

• US 3,836,033 A
• Filed: 03/19/1973
• Issued: 09/17/1974
• Est. Priority Date: 03/23/1972
• Status: Expired due to Term

• Current Assignee: Armando Podesta
• Original Assignee: Armando Podesta
• Inventors: Podesta, Armando
• Primary Examiner(s): Norton, Donald F.
• Application Number:
  US05/342,408
• Time in Patent Office: 547 Days
• Field of Search: 215/7,97
• US Class Current: 215/365
• CPC Class Codes: B65D 51/145 by means of an additional element connected directly to the container

Abstract

A metal cap for closing a container, e.g. a glass container for foodstuffs, of the kind comprising a cap base extending over the container mouth and beyond its outer edge and a separate encircling cap skirt secured to the container by a screw or bayonet connection and engaging over the edge of the cap base; the cap base being originally curved inwards, but being forced into an outward curve by the anchoring forces acting on its edge when the skirt is secured over it and subsequently being curved inwards again by reduced pressure formed in the container. Loss of pressure is thus indicated by a return to the outwardly curved condition. The region of the cap base projecting beyond the outer edge of the container mouth has a downwardly widening conical edge portion engaged by a rolled-in bead on the upper end of the cap skirt. The adjacent portion of the cap skirt may be conically tapered, and the conical edge portion of the cap base may terminate in an out-turned stiffening flange. The circle of contact preferably lies slightly below the plane of the container mouth. Good engagement and sealing are thereby obtained as well as reliable inward and outward curving of the cap base.

Claims

1. A metal cap for closing a container, particularly a glass container, comprising a cap base which is adapted to extend over the container mouth and beyond the outer edge thereof and which, in the unstressed condition, that is to say before the cap is secured on the container, is originally curved inwards and is adapted to be first resiliently curved outwards by anchoring forces acting on its periphery when the cap is secured to the container, and then to be curved inwards again by reduced pressure in the container, and An encircling cap skirt which is adapted to be secured to the container by a screw or bayonet connection, is separate from the cap base, and engages over an edge portion of the latter, wherein in its region which projects beyond the outer edge of the container mouth the cap base has a downwardly directed conical edge portion which widens in the downward direction and on which rests a rolled-in bead provided on the upper end of the encircling cap skirt at a distance from the outer edge of the container mouth.

2. A metal cap according to claim 1, wherein the portion of the encircling cap skirt adjoining the rolled-in bead is tapered conically.

3. A metal cap according to claim 1, wherein the circle of contact between the rolled-in bead of the encircling cap skirt and the outer conical edge portion of the cap base, over which the said skirt engages, lies approximately in the plane of the container mouth or preferably slightly below this plane, when the cap is fully secured on the container.

4. A metal cap according to claim 1, wherein the conical edge portion of the cap base terminates at the bottom in a stiffening flange bent over in the outward direction.

5. A metal cap according to claim 1, wherein the cap base has an annular transition portion in its region intended to rest on the container mouth between the middle portion of the cap base, which is orginally curved inwards and which is adapted to be curved outwards, and the conical edge portion of the cap base, this transition portion being originally, that is to say before the securing of the cap on the container, inclined inwards and downwards in relation to the axis of the container mouth and on the securing of the cap on the container this transition portion is adapted to pivot about the edge of the container mouth, first through the action of the anchoring pressure applied by the encircling cap skirt, into a position in which it is inclined outwards and downwards in relation to the axis of the container mouth and then, through the action of the reduced pressure in the container and of the consequent inward curving of the cap base, into an end position which is approximately horizontal or perpendicular to the axis of the container mouth.