Apparatus and methods for selective thermoforming

Abstract

Apparatus and methods of forming selected portions of integral sheets of material are disclosed. Unformed portions of the sheets may remain undistorted during the forming process, allowing them to contain text, art work, or other desired information without material risk of the information being degraded or becoming unintelligible during the forming process. This result may be accomplished, moreover, with less trim than usually occurs in conventional forming processes.

1 . Apparatus for thermoforming a plastic material, comprising:
 a. a mold;   b. means for positioning a plastic material adjacent the mold, the plastic material defining integral first and second regions; and   c. means for selectively heating the first region to its forming temperature while maintaining the second region at less than its forming temperature when the plastic material is positioned adjacent the mold.   
     
     
         2 . Apparatus according to  claim 1  in which the mold is configured to be evacuated and the selective heating means is configured so as to thermoform the first region but not thermoform the second region following evacuation of the mold. 
     
     
         3 . Apparatus according to  claim 2  in which the selective heating means includes:
 a. a source of energy; and 
 b. an energy sink. 
 
     
     
         4 . Apparatus according to  claim 3  in which the energy sink has a depth and at least one cut-out extending through the depth. 
     
     
         5 . Apparatus according to  claim 4  in which the mold defines an upper surface and comprises at least one plug protruding therefrom. 
     
     
         6 . Apparatus according to  claim 5  in which the energy sink is configured so that the at least one cut-out may be aligned with the at least one plug. 
     
     
         7 . Apparatus according to  claim 6  further comprising the plastic material positioned between the energy sink and the upper surface of the mold. 
     
     
         8 - 16 . (canceled) 
     
     
         17 . Apparatus according to  claim 5  in which the plug is generally cylindrical in shape with at least one circumferential notch. 
     
     
         18 . Apparatus according to  claim 2  in which (a) the plastic material comprises (i) printing in the second region and (ii) a holder of a coin in the first region and (h) the selective heating means avoids material distortion of the printing in the second region. 
     
     
         19 . Apparatus according to  claim 4  in which (a) the plastic material comprises (i) printing in the second region and (ii) a holder of a coin in the first region and (b) the selective heating means avoids material distortion of the printing in the second region. 
     
     
         20 . Apparatus according to  claim 7  in which (a) the plastic material comprises (i) printing in the second region and (ii) a holder of a coin in the first region and (b) the selective heating means avoids material distortion of the printing in the second region.