Apparatus and method for reforming sheet material

Abstract

A mold has a sealing surface bearing a sealing profile. A plenum has a sealing surface bearing a sealing profile. The mold and plenum together form an apparatus for reforming a sheet material. In the closed position of the apparatus, the sealing profile of the mold is in opposing relation to the sealing profile of the plenum and the sealing profiles of the mold and plenum together define a profiled sealing gap. When the sheet material is wedged into the profiled sealing gap, a direct seal will be formed between the sheet material and each of the mold and plenum, resulting in two forming areas within the apparatus.

1 . A method of reforming a sheet material, comprising:
 creating a first forming area adjacent to a mold by forming a first direct seal between the sheet material and a first sealing surface of the mold using a first sealing profile on the first sealing surface;   creating a second forming area adjacent to a plenum by forming a second direct seal between the sheet material and a second sealing surface of the plenum using a second sealing profile on the second sealing surface;   vacuum forming the sheet material by pulling the sheet material against a surface of the mold using vacuum drawn from the first forming area through the mold; and   pressure forming the sheet material by forcing the sheet material against the mold surface using pressurized gas fed to the second forming area through the plenum.   
     
     
         2 . The method of  claim 1 , wherein the first direct seal and second direct seal are formed by closing the mold against the plenum such that the first sealing profile is in opposing relation to the second sealing profile and the first and second sealing profiles together form a profiled sealing gap, and wherein the sheet material is wedged in the profiled sealing gap to form the first direct seal and the second direct seal. 
     
     
         3 . The method of  claim 1 , further comprising reinforcing the first direct seal by drawing the sheet material against the first sealing profile by vacuum. 
     
     
         4 . The method of  claim 1 , wherein the vacuum forming and pressure forming are performed simultaneously. 
     
     
         5 . The method of  claim 1 , wherein the sheet material is made of glass or glass-ceramic. 
     
     
         6 . The method of  claim 1 , wherein one of the first and second sealing profiles is in the form of a groove in the respective sealing surface and the other of the first and second sealing profiles is in the form of a bump in the respective sealing surface.