Abstract A continuous curl formed on the periphery of a can end component prior to the first and second operations of double seaming the can end component to an end of a can body has an inner annular portion of a configuration substantially that of a surface of revolution generated by three successive merging arcs including an inner arc struck by a first radius R1, a middle arc struck by a second radius R2, and an outer arc struck by a third radius R3, where R1< R2< R3, and an outer annular portion of a configuration substantially that of a generally planar surface which is parallel to a plane formed by the innermost marginal edge of the inner arc of the inner annular portion of the continuous curl. A curler tool for forming the continuous curl has a curl-forming groove which has a contour substantially the same as the configuration of the inner and outer annular portions of the continuous curl formed by the curler tool.
A curler tool for forming a continuous curl on the periphery of a can end component prior to the first and second operations of double seaming said can end component to an end of a can body, said tool comprising: a body; and a curl-forming groove formed in said body and defined by an inner surface having a contour substantially that of a surface of revolution generated by three successive merging arcs including an inner arc struck by a first radius R1, a middle arc struck by a second radius R2, and an outer arc struck by a third radius R3, where R1 > R2 > R3, and an outer surface having a contour substantially that of a generally planar surface which is in a plane substantially parallel to a plane formed by the innermost marginal edge of said inner arc.
Claim 2
Dependent Claim
141 words
A curler tool for forming a continuous curl on the periphery of a can end component prior to the first and second operations of double seaming said can end component to an end of a can body, said tool comprising: a body; and a curl-forming groove formed in said body and defined by an inner surface having a contour substantially that of a surface of revolution generated by three successive merging arcs including an inner arc struck by a first radius R1, a middle arc struck by a second radius R2, and an outer arc struck by a third radius R3, where R1 > R2 > R3, and an outer surface having a contour substantially that of a generally planar surface which is in a plane substantially parallel to a plane formed by the innermost marginal edge of said inner arc.
Claim 3
Dependent Claim
19 words
A curler tool according to claim 1 wherein R1 is approximately equal to 3R2, and approximately equal to 6R3.
Claim 4
Dependent Claim
24 words
A curler tool according to claim 1 wherein R1 approximately equals 0.166 inch, R2 approximately equals 0.050 inch, and R3 approximately equals 0.025 inch.