Containers
AssigneeMetal Box Limited
InventorsJozef Tadeusz Franek, Peter Henry Doncaster
Life of this patent
Estimating the term…
Abstract
In a method of forming a neck and flange at the open end of a thin cylindrical metal can body, the can body is held endwise under compression while an axial shortening force and a radial deforming force are applied to the can body sidewalls, by relative axial movement between the can body on the one hand and, on the other hand, an external forming tool and an internal tool edge which are kept at constant axial spacing from each other, so that the neck and flange are formed in free space without any need for internal or external tools shaped to the required profile; any desired shape can be obtained by varying the characteristics of the relative axial and radial motions.
Claims19
A method of forming a cylindrical metal can body of the type having an open end with a peripheral end flange about the open end of the can body and a neck portion of reduced diameter merging with said flange, said method comprising the steps of supporting the can body in axial compression and then while so holding the can body in axial compression applying a radial force inwardly on the can body deforming the can body radially inwardly adjacent the can body open end to thereby simultaneously inwardly neck the can body and axially shorten the can body.
A method of forming a cylindrical metal can body having an open end with a peripheral end flange about the open end of said body and a neck portion merging with the flange, said method comprises the steps of:
- supporting the can body axially between a can bottom support element and an axial thrust member with a terminal edge portion of the can body at its open end engaging the thrust member, positioning a pilot element having a circumferential first tool edge disposed with the first tool edge coaxially within the can body;
- providing a forming element having a second tool edge, radially inwardly engaging the exterior of the can body with the second tool edge and effecting relative axial movement between, on the one hand, the can body and support element and, on the other hand, the pilot element and the forming element having the second tool edge engaging the can body while effecting relative radial movement between the can body and the second tool edge and relative axial movement between said support element and thrust member such as to maintain the can body under continuous compression while shortening it, whereby said flange and said neck are formed on the can body in free space by the second tool edge with the first tool edge acting as a fulcrum for deforming the can body between the trust member and the forming element, and the first and second tool edges being maintained in respective planes at a constant axial spacing from each other.
Apparatus for forming a cylindrical can body having a bottom end and an open end with a peripheral end flange about the open end of the can body and a neck portion merging with the flange, said apparatus including opposed first and second axial support means defining a main axis and being adapted for respectively supporting the bottom end and engaging a terminal edge portion of the open end of the can body and maintaining the can body in axial compression thereby, inward radial force applying means adjacent said second axial support means and being movable radially with respect to said main axis, and a pilot element extending coaxially through said second axial support means towards said first axial support means and having a circumferential first tool edge, said inward radial force applying means having a second tool edge at a fixed axial spacing from and axially nearer to said first axial support means than said first tool edge, and first and second axial support means being arranged for axial movement relative to said tool edges and relative to each other such as to shorten the axial distance between said first and second axial support means.
Apparatus for forming a cylindrical metal can body having an open end with a peripheral end flange about the open end of the can body and a neck portion merging with the flange, said apparatus comprising:
- a can bottom support element defining a main axis;
- an axial thrust member coaxial with but spaced axially from said support element and adapted to engage endwise a terminal edge of the can body at the open end thereof;
- a pilot element extending coaxially through said thrust member towards said support element and having a circumferential first tool edge;
- and a forming element having a second tool edge at a fixed axial spacing from and axially nearer to the support element than said first tool edge, said second tool edge being offset from and facing said main axis, said support element and thrust member being arranged for axial approaching movement relative to each other, said thrust member and pilot element being arranged for radial movement relative to each other, and said forming element and pilot element being arranged for radial movement relative to each other.
A method forming a cylindrical metal can body having an open end with a peripheral end flange about the open end and a neck portion merging with the flange, said method comprising the steps of providing a can body having an initial flange, endwise clamping the can body between two support members to axially compress the can body, simultaneously rotating the two support members and the can body about a fixed axis, engaging the can body externally with a radially inwardly directed force applying member spaced from but adjacent to the initial flange to radially inwardly neck the can body, and then while maintaining the axially compressive force on the can body effecting relative axial movement of the can body and the force applying member in a direction to effect relative movement of the initial flange towards the force applying member and to increase the axial extent of the neck while foreshortening the can body followed by the reforming of the flange.
Dependencies are inferred from the claim text.