Method of forming a pilferproof closure

A method of forming a pilferprof closure comprising in sequence the steps of:

• (a) stamping a disc out of a sheet of metallic material and drawing said disc into a cup-shaped shell having an end wall and an annular sidewall depending therefrom;
• (b) rolling an annular ring in said sidewall such that said ring has a diameter greater than the outside diameter of said sidewall;
• (c) forming a circumferential scoreline consisting of alternately arranged slits and fracturable bridges in a right cylindrical portion of said sidewall below and adjacent to said annular ring, said scoreline bifurcating said sidewall into an upper portion which is susceptible to being deformed about a threaded neck of a container and a lower portion which is adapted to be at least partly turned inwardly and into engagement with an annular shoulder formed on said container below said threaded neck;
• (d) supporting said sidewall in the zone of said scoreline against inward collapse;
• and
• (e) while supporting said sidewall, compressing said annular ring to form a bead with extends from said upper portion of said sidewall and downwardly over said scoreline.

A method of forming a roll-on, pilferproof closure for fitment to a container having a threaded neck and an annular shoulder formed below said threaded neck, said method comprising in sequence the steps of:

• (a) stamping a disc out of a sheet of aluminum;
• (b) drawing said disc into a cup-shaped member having an end wall and an annular sidewall depending therefrom;
• (c) forming an annular ring in said sidewall such that said ring has a diameter greater than at least a section of said sidewall;
• (d) forming a cylindrical scoreline consisting of alternately arranged slits and bridges in a right cylindrical portion of said sidewall below and adjacent to said annular ring, said scoreline bifurcating said sidewall into an upper portion which is susceptible to being deformed about said threaded neck and a lower portion which is adapted to be at least partly turned inwardly and into engagement with said annular shoulder;
• (e) supporting said sidewall in the zone of said scoreline against inward collapse;
• and
• (f) while supporting said sidewall, compressing said annular ring to form a bead which extends outwardly and downwardly from said upper portion of said sidewall and shields edges of fracturable bridges upon removal of said closure from said container.

A method of forming a roll-on, pilferproof closure for fitment to a container having a threaded neck and an annular shoulder formed below said threaded neck, said method comprising in sequence the steps of:

• (a) stamping a disc out of a sheet of metallic material and drawing said disc into a cup-shaped shell having an end wall and an annular sidewall depending therefrom, said shell having a uniform height;
• (b) rolling an annular ring in said sidewall such that said annular ring has a diameter greater than at least a section of said sidewall;
• (c) forming a circumferential scoreline consisting of alternately arranged slits and fracturable bridges in a right cylindrical portion of said sidewall below and adjacent to said annular ring, said scoreline bifurcating said sidewall into an upper portion and a lower portion;
• (d) supporting said sidewall in the zone of said scoreline against inward collapse;
• (e) while supporting said sidewall, compressing said annular ring to form a bead which extends outwardly and downwardly from said upper portion of said sidewall and over said scoreline;
• (f) placing said cup-shaped shell onto said container;
• and
• (g) rolling said upper portion of said sidewall against said threaded neck and rolling at least part of said lower portion of said sidewall inwardly and into engagement with said annular shoulder such that said lower portion will remain on said container after said closure is unthreaded.