×

Twin-sheet thermoforming process with shell reinforcement

  • US 5,635,129 A
  • Filed: 06/06/1995
  • Issued: 06/03/1997
  • Est. Priority Date: 05/02/1990
  • Status: Expired due to Fees
First Claim
Patent Images

1. A process for producing a reinforced twin-sheet thermoformed thermoplastic article having a reinforced portion, the process comprising the steps of:

  • (a) heating first and second sheets of thermoplastic material;

    (b) forming the first sheet in a first mold;

    (c) forming the second sheet in a second mold;

    (d) pressing the heated second sheet in the second mold into contact with the heated first sheet in the first mold such that the two sheets are fused together at selected areas of contact and mate to form a hollow cavity at a selected reinforced location; and

    (e) injecting under pressure a quantity of liquid thermoplastic material through at least one of the molds and one of the sheets into the cavity to substantially fill the cavity with thermoplastic material so that the quantity of liquid thermoplastic material fuses with the two sheets defining the cavity to form an article having a continuous integral reinforced portion of a desired shape and thickness at the selected reinforced location.

View all claims
  • 1 Assignment
Timeline View
Assignment View
    ×
    ×