Method and apparatus for forming a fully curled neck on a drawn and ironed pressure can

Claim 2

A two-station method of forming a conical shoulder and a fully curled neck on an end of a preformed cup, comprising: the steps performed at the first station including reforming the end panel of said cup into a conical shoulder and a top flat central panel formed integral with said shoulder, drawing said top central panel into an upstanding cylindrical throat, having a first predetermined height, and a top flat center panel formed integral with said throat, removing a centrally located, circular portion of said top flat center panel to leave a top annular rim formed integral with said upstanding cylindrical throat, and drawing said cylindrical throat having said integrally-formed top annular rim into an open-ended upstanding cylindrical throat having a second predetermined height which is greater than said first predetermined height; and the steps performed at the second station including moving the top of said open-ended upstanding cylindrical throat along a toroidal path to form a fully curled neck on said conical shoulder, said moving step is achieved by supporting said conical shoulder of said reformed end panel on an internal support mandrel, said mandrel having a convexlyconical support surface profile, clamping said conical shoulder of said reformed end panel between said mandrel surface and an external sleeve member, said member having a concavely-conical mating surface profile, to align said open-ended cylindrical throat, integrally-formed with said shoulder, with an external curling groove surface having a toroidal profile of an external curling member, and forcing said open-ended throat in contact with said groove surface along the toroidal path defined by said surface.

Claim 3

A two-station method of forming a conical shoulder and a fully curled neck on an end of a preformed cup, according to claim 1, wherein at said first station said reforming step is achieved by pressing the end panel of said preformed cup between mating external and internal die assemblies, said external die assembly having a concavely-conical mating surface profile and said internal die assembly having a convexly-conical mating surface profile, said first drawing step is achieved by exposing an internal throat drawing die component of said internal die assembly, to said top central panel of said reformed end, said removing step is achieved by perforating said circular portion of said top center panel with an internal male piercing punch component of said internal die assembly in cooperation with a cut-edge defined on an external female die component of said external die assembly, and said second drawing step is achieved by pulling said cylindrical throat having said internally formed top annular rim past said internal throat drawing die component, which action wipes out said top annular rim.

Claim 4

A two-station method of forming a conical shoulder and a fully curled neck on an end of a preformed cup, according to claim 1, wherein at said first station said reforming step is achieved by pressing the end panel of said preformed cup between mating external and internal die assemblies, said external die assembly having a concavely-conical mating surface profile and said internal die assembly having a convexly-conical mating surface profile, said first drawing step is achieved by exposing an internal female die component of said internal die assembly, to said top central panel of said reformed end, said removing step is achieved by perforating said circular portion of said top center panel with an external male piercing punch component of said external die assembly in cooperation with a cut-edge defined on the internal female die component of said internal die assembly, and said second drawing step is achieved by pulling said cylindrical throat having said integrally-formed top annular rim past said internal female die component, which action wipes out said top annular rim.

Claim 5

A two-station method of forming a conical shoulder and a fully curled neck on an end of a preformed cup, according to claim 1, wherein said steps performed at the first station are performed sequentially and continuously along a linear path of travel in one direction.

Claim 6

A two-station method of forming a conical shoulder and a fully curled neck on an end of a preformed cup, according to claim 2, wherein said steps performed at the first station are performed sequentially and continuously along a linear path of travel in one direction.

Claim 7

A two-station method of forming a conical shoulder and a fully curled neck on an end of a preformed cup, according to claim 3, wherein said steps performed at the first station are performed sequentially and continuously along a linear path of travel in one direction.

Claim 8

Apparatus positioned at two stations for forming a conical shoulder and a fully curled neck on an end of a preformed cup, comprising: the apparatus positioned at the first station including means for reforming the end panel of said cup into a conical shoulder and a top flat central panel formed integral with said shoulder, means for drawing said top central panel into an upstanding cylindrical throat, having a first predetermined height, and a top flat center panel formed integral with said throat, means for removing a centrally located, circular portion of said top flat center panel to leave a top annular rim formed integral with said cylindrical throat, and means for drawing said cylindrical throat having said integrally formed top annular rim into an open-ended upstanding cylindrical throat having a second predetermined height which is greater than said first predetermined height; and the apparatus positioned at the second station including means for moving the top of said open-ended upstanding cylindrical throat along a toroidal path to form a fully curled neck on said conical shoulder, said moving means comprises: a mating internal support mandrel and a mating external sleeve member for supporting and clamping said conical shoulder of said reformed end panel therebetween, said internal support mandrel having a convexly-conical mating surface profile and said external sleeve member having a concavely-conical mating surface profile; and an external curling member including an external curling groove surface having a toroidal surface profile, said internal support mandrel positioned relative to said external curling member to align said open-ended cylindrical throat with said curling groove surface and one of said external curling member and internal support mandrel displaceable relative to the other to force said open-ended throat in contact with said groove surface along the toroidal path defined by said surface.

Claim 9

Apparatus positioned at two stations for forming a conical shoulder and a fully curled neck on an end of a preformed cup, comprising: the apparatus positioned at the first station including means for reforming the end panel of said cup into a conical shoulder and a top flat central panel formed integral with said shoulder, means for drawing said top central panel into an upstanding cylindrical throat, having a first predetermined height, and a top flat center panel formed integral with said throat, means for removing a centrally located, circular portion of said top flat center panel to leave a top annular rim formed integral with said cylindrical throat, and means for drawing said cylindrical throat having said integrally formed top annular rim into an open-ended upstanding cylindrical throat having a second predetermined height which is greater than said first predetermined height; and the apparatus positioned at the second station including means for moving the top of said open-ended upstanding cylindrical throat along a toroidal path to form a fully curled neck on said conical shoulder, said moving means comprises: a mating internal support mandrel and a mating external sleeve member for supporting and clamping said conical shoulder of said reformed end panel therebetween, said internal support mandrel having a convexly-conical mating surface profile and said external sleeve member having a concavely-conical mating surface profile; and an external curling member including an external curling groove surface having a toroidal surface profile, said internal support mandrel positioned relative to said external curling member to align said open-ended cylindrical throat with said curling groove surface and one of said external curling member and internal support mandrel displaceable relative to the other to force said open-ended throat in contact with said groove surface along the toroidal path defined by said surface.

Claim 10

Apparatus positioned at two stations for forming a conical shoulder and a fully curled neck on an end of a preformed cup, according to claim 7, wherein at said first station, said reforming means comprises mating external and internal die assemblies for pressing the end panel of said preformed cup therebetween, said external die assembly having a concavely-conical mating surface profile and said internal die assembly having a convexly-conical mating surface profile, said first drawing means comprises an internal throat drawing die component of said internal die assembly, which is displaceable relative to mating external and internal reforming die components of said respective external and internal die assemblies, said removing means comprises an internal male piercing punch component of said internal die assembly, which is displaceable relative to said mating external and internal reforming die components and said internal throat drawing die component And insertable into an external female cut-edge die component of said external die assembly, and said second drawing means comprises said internal throat drawing die component, which is further displaceable relative to said mating external and internal reforming die components.

Claim 11

Apparatus positioned at two stations for forming a conical shoulder and a fully curled neck on an end of a preformed cup, according to claim 7, wherein at said first station, said reforming means comprises mating external and internal die assemblies for pressing the end panel of said preformed cup therebetween, said external die assembly having a concavely-conical mating surface profile and said internal die assembly having a convexly-conical mating surface profile, said first drawing means comprises an internal female die component of said internal die assembly, which is displaceable relative to mating external and internal reforming die components of said respective external and internal die assemblies, said removing means comprises an external male piercing punch component of said external die assembly, which is displaceable relative to said mating external and internal reforming die components and said internal female die component and insertable into said internal female die component to cooperate with a cut-edge defined on the internal female die component, and said second drawing means comprises said internal female die component, which is further displaceable relative to said mating external and internal reforming die components and said external male piercing punch component.

Claim 12

Apparatus positioned at two stations for forming a conical shoulder and a fully curled neck on an end of a preformed cup, according to claim 7, wherein the component means of said apparatus positioned at the first station operate sequentially and continuously along a linear path of travel in one direction.

Claim 13

Apparatus positioned at two stations for forming a conical shoulder and a fully curled neck on an end of a preformed cup, according to claim 8, wherein the component means of said apparatus positioned at the first station operate sequentially and continuously along a linear path of travel in one direction.

Claim 14

Apparatus positioned at two stations for forming a conical shoulder and a fully curled neck on an end of a preformed cup, according to claim 9, wherein the component means of said apparatus positioned at the first station operate sequentially and continuously along a linear path of travel in one direction.