| 摘要 |
Continuous impression forming of three-dimensional products from heated, formable thermoplastic materials between top and bottom mold carriages each having a three-dimensional forming belt mold revolvable around the carriage. Each three-dimensional forming belt mold includes a flexible silicone rubber mold adhered to a multi-ply woven fabric belt. A surface of desired shape on one revolving rubber mold mates with the desired shape of an opposed revolving rubber mold forming a continuously moving mold channel between the mold belts into which is fed hot thermoplastic material at moldable temperature. After discharging molded plastic product from the exit of the moving mold channel, localized surface heat in the rubber molds resulting form contact with hot plastic is removed by air blown directly onto the rubber mold surfaces. Each carriage frame includes a back-up plate coated with low friction coefficient material over which slides a continuously moving belt mold. These slippery plates have numerous air-bearing holes feeding air between them and the respective moving woven fabric belt for reducing friction and wear. The woven fabric belts are guided and they are driven by an electric drive motor, with or without torque-motor assistance, for revolving both belt molds in unison maintaining their mating alignment. Electric screw jacks raise the top carriage, extend/retract grooved exit rolls, fine-tune alignment of revolving belt molds by adjusting grooved exit rolls and adjust the machine relative to the in-feed of heated thermoplastic materials.
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