초록 ▼

A drawn container is disclosed having a substantially cylindrical sidewall extending upwardly from an integral base portion to form an open neck which is double seamed with a top end closure. The base portion has a downwardly extending, generally U-shaped, circumferential nose portion, the outside s

A drawn container is disclosed having a substantially cylindrical sidewall extending upwardly from an integral base portion to form an open neck which is double seamed with a top end closure. The base portion has a downwardly extending, generally U-shaped, circumferential nose portion, the outside surface of which defines the plane of the base of the container on which the container normally sets. The nose portion is defined by a radius between a substantially vertical inner wall and an outside wall. The outside wall extends from a lower portion of the sidewall through a convex lower body radius to a concave profile radius disposed above the nose portion. A frustoconical portion is provided between the convex lower body radius and the concave profile radius. The frustoconical portion forms a lower body angle of at least 30°with respect to the plane of the base of the container. An inwardly directed bottom dome extends inwardly of the inner wall and has at least three progressively increasing radii of curvature in the direction of the center of the dome. A method is also disclosed for reforming the base portion of the above-described container. This method includes the steps of holding the substantially vertical disposition and the diameter of the inner wall defining the nose portion while simultaneously moving a reforming tool against the outside wall of the nose portion to tighten the nose radius therebetween and form the concave profile radius of the base portion while retaining a lower body angle greater than 30°, and retaining the progressively increasing radii of curvature in the bottom dome.

대표청구항 ▼

In a drawn container having a generally cylindrical sidewall extending upwardly from an integral base portion forming an open neck adapted to be double seamed with a generally circular top end closure to provide a seamed pressure-holding container, said base portion having a downwardly extending, ge

In a drawn container having a generally cylindrical sidewall extending upwardly from an integral base portion forming an open neck adapted to be double seamed with a generally circular top end closure to provide a seamed pressure-holding container, said base portion having a downwardly extending, generally U-shaped circumferential nose portion defined by an inner wall, an outside wall and a concave outside nose radius therebetween, the outside surface of the nose radius defining plane of the base of the container, and an inwardly domed central portion, the improvement comprising said base portion being a reformed base portion wherein a radius of curvature of the nose portion of said base portion is tightened having: a gauge of less than about 0.0116 inch, a substantially vertically disposed inner wall of the nose portion, the outside wall of the nose portion extending from a lower portion of the cylindrical sidewall through a convex lower body radius to a concave profile radius disposed above the nose portion, with a first frustoconical wall portion between the convex lower body radius and the concave profile radius, said first frustoconical wall portion forming a lower body angle of at least 30°with respect to the plane of the base of the container, and a second frustoconical wall portion between the concave profile radius and the concave outside nose radius, said second frustoconical wall portion disposed at an angle of from about 60°to about 90°with respect to the plane of the base of the container, with the angle of disposition of the second frustoconical wall portion being greater than the lower body angle of the first frustoconical wall portion, and the inwardly domed central portion extending inwardly of the inner wall, having at least three progressively increasing radii of curvature in the direction of the center of the dome.