Patent · US Expired

Method of thermoforming a sheet material

US5911943A · kind A · utility

17Cited by
4References
4Claims
0Family size

Inventors

Key dates

Filing dateJul 7, 1997
Grant dateJun 15, 1999
Priority date
Expiry dateJul 7, 2017

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10T428/31935
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

The present invention relates to a method of thermoforming a sheet material around an insert to make a thermoformed article. The sheet material may include poly(methyl) methacrylate and other thermoplastic sheet material. The inserts become an integrated part of the thermoformed product, and are characterized by having at least one removable portion or plug. The plug(s) are removed during the thermoforming process, and allow the thermoformed sheet material to shrink without creating undesirable levels of stress in the sheet material. This prevents cracking or other failure of the sheet material.

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.