Patent · US Expired

Apparatus for making plastic skylights

US4278414A · kind A · utility

11Cited by
16References
6Claims
0Family size

Assignee

Inventors

Key dates

Filing dateFeb 16, 1979
Grant dateJul 14, 1981
Priority date
Expiry dateFeb 16, 1999

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S425/048
  • WIPO fieldOther special machines
  • WIPO sectorMechanical engineering

Abstract

Apparatus for making skylights from thin polymer sheets. Heated clamp frames are provided for clamping the perimeter of a thin polymer sheet and preheating the perimeter thereof to a preselected first temperature. An oven is provided for further heating the preheated perimeter and for heating the center portion of the polymer sheet to a selected second temperature greater than the first temperature to soften the polymer for forming. Upper and lower perimeter platens are provided having a plurality of stepped edges therein which are clamped onto the softened polymer sheet to thereby form a plurality of steps within the perimeter of the polymer sheet. A vacuum forming chamber is provided for forming a dome in the center portion of the polymer sheet above the stepped portion thereof. A push member may also be provided adjacent the upper platen for forming a sharp rise or push around the perimeter of the dome and between the steps and the dome.

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