Patent ID: 7958922

Claim:
An apparatus for sealing a sheet of heat sealable material around a workpiece, the apparatus comprising: a) a workpiece holding fixture, which comprises: i) a platen having an upper surface and a lower surface; ii) a workpiece holding die disposed on the upper surface of the platen and including a deformable body comprising a pocket shaped to correspond to the perimeter of the workpiece; iii) a workpiece support disposed in a lower portion of the pocket of the deformable body; and iv) an ejection tool comprising a piston disposed in a cavity in the workpiece support and a shaft connected to the piston and passing through a hole in the workpiece support; b) a heater assembly, which comprises: i) inner and outer hold-down plates forming a heater channel there between; and ii) a heating element including an upper portion disposed in the heater channel and a cutting edge extending beyond the inner and outer hold-down plates, wherein a portion of the heating element is shaped to match a corresponding portion of the pocket of the deformable body; and c) wherein when the heater assembly and the workpiece holding fixture are moved together with the workpiece disposed in the pocket of the deformable body having a sheet of heat sealable material laying against a lower workpiece surface, an intermediate workpiece sidewall and an upper workpiece surface, the cutting edge of the heater element cuts overlapping layers of the heat sealable material against the upper surface of the deformable body.