Continuous molding of thermoplastic materials
Abstract
Abstract THREE-DIMENSIONAL MOLDED PRODUCTS ARE MADE FROM THERMOPLASTIC MATERIALS IN A CONTINUOUS INJECTION MOLDING PROCESS WHEREIN A MOLD SURFACE HAVING DEEP CAVITIES THEREIN ADVANCED WITH RESPECT TO A STATIONARY EXTRUDER MATED AGAINST THE MOLD SURFACE SO THAT COMMUNICATION EXISTS BETWEEN THE CAVITIES AND THE EXTRUDER CAUSING A FLOWABLE THERMOPLASTIC MATERIAL TO BE FORCED INTO SAID CAVITIES UNDER HIGH PRESSURE BY ISOLATING THE CAVITIES FROM THE REMAINDER OF THE MOLD. ON THE MOLD SURFACE A CONTINUOUS MATRIX IS FORMED HAVING PROJECTIONS ATTACHED THERETO AND EXTENDING INTO THE CAVITIES OF THE MOLD. THE MATRIX IS FORMED UNDER A LOWER PRESSURE THAN THE PROJECTIONS. AFTER COOLING, THE PRODUCT IS STRIPPED FROM THE MOLD.
Inventors
- 👤 Jack Doleman
- 👤 William H Hills
Bibliographic Details
Claims Analysis
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| 7.5 Years (Year 8) | 1978-06-28 | 1978-12-28 | 1979-06-29 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1982-06-28 | 1982-12-28 | 1983-06-29 | $7700.00 | Window Closed / Lapsed |