Method and apparatus for severing three dimensional thermoplastic articles

A method for producing thermoplastic articles formed on a sheet of material comprising the steps of:

• thermoforming a web of uncut thermoplastic articles from said sheet of material, said formed web consisting of a plurality of uncut thermoplastic articles and a plurality of projecting deformations surrounding said uncut thermoplastic articles;
• supplying said web of uncut thermoplastic articles to a trimming apparatus which comprises a movable punch portion and a die portion, said movable punch portion including a plurality of retractable male locating pins and at least one cutting edge, said plurality of retractable locating pins projecting beyond said cutting edge, said die portion including a plurality of retractable female locating pins and at least one die opening, said plurality of retractable female locating pins projecting beyond said at least one die opening;
• approximately aligning said thermoplastic articles with said at least one cutting edge of said movable punch portion and said at least one edge of said die portion;
• driving said male locating pins into contact with inner sides of said projecting deformations;
• exerting force on said inner sides of said projecting deformations to drive an outer side of said projecting deformations into contact with said female locating pins;
• holding said projecting deformations between said male and female locating pins to thereby align at least one of said thermoplastic articles between said at least one cutting edge and said at least one die edge prior to engagement of said web with either of said at least one cutting edge or said at least one die opening;
• retracting said female locating pin a distance sufficient to allow said at least one die edge to contact edges of at least one of said thermoplastic articles;
• retracting said male locating pin a distance sufficient to allow said at least one cutting edge to contact edges of at least one of said thermoplastic articles;
• and
• severing said thermoplastic articles from said web.

Apparatus for severing thermoplastic articles from a web having a plurality of uncut thermoplastic articles surrounded by a plurality of projecting deformation, comprising:

• means for cutting said uncut thermoplastic articIes from said web, said cutting means comprising a movable punch, at least one cutting edge attached to said movable punch, each of said cutting edges of similar shape and size of said uncut articles, and a stationary die having at least one opening of similar shape and size of said uncut articles;
• means for supplying said web of uncut articles to said cutting means;
• means for approximately aligning edges of said uncut articles with said cutting means;
• and
• means for precisely locating edges of said uncut articles with said cutting means;
• wherein said precise locating means further comprises retractable male locating means for engaging one side of said projecting deformations and retractable female locating means for engaging a second side of said projecting deformations prior to engagement of said web with said cutting means, said retractable male locating means for engaging one side of said projecting deformations is attached to and retractable within said movable punch and said retractable female locating means for engaging a second side of said projecting deformations is attached to and retractable within said stationary die.

Apparatus for severing thermoplastic articles from a web having a plurality of uncut thermoplastic articles surrounded by a plurality of projecting deformations, comprising:

• a movable punch;
• at least one cutting edge attached to and projecting from said movable punch, each of said at least one cutting edge of similar shape and size to one of said uncut thermoplastic articles;
• at least one retractable male locating pin attached to said movable punch, each of said at least one retractable male locating pin projecting beyond said cutting edge;
• a stationary trim die;
• at least one die opening in said trim die, each of said at least one die opening being of similar shape and size to one of said uncut thermoplastic articles;
• at least one retractable female locating pin attached to said trim die, each of said retractable female locating pins projecting beyond said at least one die openings;
• wherein said projecting male locating pin first engages one side of said projecting deformation and drives said projecting deformation into said retractable female locating pin to align said uncut thermoplastic article with said cutting edge and said die opening prior to engagement of said web with either of said at least one cutting edge or said at least one die opening, said male and female retractable locating pins retracting when said cutting edge approaches said article to permit said cutting edge to engage said uncut article along its edge.