Compression molding process and article made by the process
AssigneeSeaquist Closures Foreign, Inc.
InventorsBruce M. Mueller, Ben Nejad, Dieter F. Lay
Life of this patent
Estimating the term…
Abstract
A molded article is produced by a method of compression molding employing a specially shaped billet of thermoplastic material which is positioned at a predetermined location in a predetermined orientation with respect to the mold cavity surfaces of a mold part. In a preferred embodiment, the billet has a generally egg shape and is located adjacent a mold surface defining a small mold cavity region between two larger cavity regions.
Claims21
A method for making a closure having a body, a lid, and a hinge connecting said body and lid, said method comprising the steps of:
- (A) providing a first mold part having (1) a first surface region defining a first side of said body, (2) a second surface region defining a first side of said hinge, and (3) a third surface region defining a first side of said lid;
- (B) at a location spaced from said first mold part, providing a second mold part having (1) a first surface region defining a second side of said body, (2) a second surface region defining a second side of said hinge, and (3) a third surface region defining a second side of said lid;
- (C) creating from a melt of thermoplastic material a billet having a predetermined shape;
- (D) positioning said billet in a predetermined orientation with at least a portion of said billet disposed adjacent said first mold part second surface region;
- (E) decreasing the space between said first and second mold parts to compress said billet so that said thermoplastic material flows between said mold parts;
- and
- (F) after said thermoplastic material has solidified to form a closure, increasing the space between said mold parts, and then removing said closure.
A method for making an article of unitary construction having a first portion, a second portion smaller than said first portion, and a third portion that is larger than said second portion, said method comprising the steps of:
- (A) providing a first mold part having (1) a first surface region defining a first side of said first portion, (2) a second surface region defining a first side of said second portion, and (3) a third surface region defining a first side of said third portion;
- (B) at a location spaced from said first mold part, providing a second mold part having (1) a first surface region defining a second side of said first portion, (2) a second surface region defining a second side of said second portion, and (3) a third surface region defining a second side of said third portion;
- (C) creating from a melt of thermoplastic material a billet having a predetermined shape;
- (D) positioning said billet in a predetermined orientation with at least a portion of said billet disposed adjacent said first mold part second surface region;
- (E) decreasing the space between said first and second mold parts to compress said billet so that said thermoplastic material flows between said mold parts;
- and
- (F) after said thermoplastic material has solidified to form an article, increasing the space between said mold parts, and then removing said article.
A closure having a unitary construction of components which includes a body, a lid, and a hinge connecting said body and lid, said closure made by the method of comprising the steps of:
- (A) providing a first mold part having (1) a first surface region defining a first side of said body, (2) a second surface region defining a first side of said hinge, and (3) a third surface region defining a first side of said lid;
- (B) at a location spaced from said first mold part, providing a second mold part having (1) a first surface region defining a second side of said body, (2) a second surface region defining a second side of said hinge, and (3) a third surface region defining a second side of said lid;
- (C) creating from a melt of thermoplastic material a billet having a predetermined shape;
- (D) positioning said billet in a predetermined orientation with at least a portion of said billet disposed adjacent said first mold part second surface region;
- (E) decreasing the space between said first and second mold parts to compress said billet so that said thermoplastic material flows between said mold parts;
- and
- (F) after said thermoplastic material has solidified to form a closure, increasing the space between said mold parts, and then removing said article.
An article of unitary construction which includes a first portion, a second portion smaller than said first portion, and a third portion that is larger than said second portion, said article made by the method of comprising the steps of:
- (A) providing a first mold part having (1) a first surface region defining a first side of said first portion, (2) a second surface region defining a first side of said second portion, and (3) a third surface region defining a first side of said third portion;
- (B) at a location spaced from said first mold part, providing a second mold part having (1) a first surface region defining a second side of said first portion, (2) a second surface region defining a second side of said second portion, and (3) a third surface region defining a second side of said third portion;
- (C) creating from a melt of thermoplastic material a billet having a predetermined shape;
- (D) positioning said billet in a predetermined orientation with at least a portion of said billet disposed adjacent said first mold part second surface region;
- (E) decreasing the space between said first and second mold parts to compress said billet so that said thermoplastic material flows between said mold parts;
- and
- (F) after said thermoplastic material has solidified to form an article, increasing the space between said mold parts, and then removing said article.
A billet for compression molding comprising:
- a mass of thermoplastic material having a shape with at least one large end and a smaller region.
A billet made by the method comprising the following steps:
- extruding a melt of thermoplastic material through an exit orifice having a generally oval plan shape to form a predetermined mass of extruded thermoplastic material extending beyond said orifice;
- permitting said mass to bulge peripherally;
- and
- severing said mass from said exit orifice to form an egg shape billet.
A method for making a billet comprising the steps of:
- extruding a melt of thermoplastic material through an exit orifice having a generally oval plan shape to form a predetermined mass of extruded thermoplastic material extending beyond said orifice;
- permitting said mass to bulge peripherally;
- and
- severing said mass from said exit orifice to form an egg shaped billet.
A billet made by the method comprising the following steps:
- extruding a melt of thermoplastic material through an exit orifice having a plan shape with at least one large end and a smaller region to form a predetermined mass of extruded thermoplastic material extending beyond said orifice;
- permitting said mass to bulge peripherally;
- and
- severing said mass from said exit orifice to form an elongate billet.
A method for making a billet comprising the steps of:
- extruding a melt of thermoplastic material through an exit orifice having a plan shape with at least one large end and a smaller region to form a predetermined mass of extruded thermoplastic material extending beyond said orifice;
- permitting said mass to bulge peripherally;
- and
- severing said mass from said exit orifice to form an elongate billet.
Dependencies are inferred from the claim text.