Formed thermoplastic article having smooth edges
AssigneeConverter Manufacturing, LLC
InventorMillard F Wallace
Life of this patent
Estimating the term…
Abstract
The disclosure relates to forming shaped thermoplastic articles having smooth peripheries. Many thermoplastic articles have sharp edges formed upon molding or cutting the article from a feedstock sheet. Such sharp edges can damage thin plastic films or flesh which they contact, and smoothing the edges is desirable. Described herein are methods of forming a smooth periphery for such sharp-edged articles by rolling over the sharp edge. The smoothing operation is performed by forming a deflectable flange including a bend region separated from the potentially sharp peripheral edge by a spacer, deflecting a portion of the deflectable flange, and softening at least one bent portion of the deflectable flange to yield a smooth periphery upon cooling.
Claims30
An article formed from a thermoformable sheet having a peripheral edge and having sufficient rigidity to define the conformation of the article, the article comprising a body having the shape of a rounded rectangular tray with a concave compartment formed therein and having an extension extending peripherally away from the body, the extension including the peripheral edge of the thermoformable sheet and a bent portion interposed between the peripheral edge and the junction between the body and the extension, the bent portion having a smooth periphery and being sufficiently bent that the peripheral edge of the thermoformable sheet is displaced from the periphery of the article, whereby the article has a smooth periphery.
An article formed from a thermoformable sheet having a peripheral edge and having sufficient rigidity to define the conformation of the article, the article comprising a body having the shape of a rounded rectangular tray with a concave compartment formed therein and having an extension extending peripherally away from the body, the extension including a deflectable flange comprising a spacer bearing a peripheral edge of the thermoformable sheet, the spacer being connected to the extension at an approximately right angle by a bend region, the bend region having a smooth contour.
Dependencies are inferred from the claim text.