Plastic and nonmetallic article shaping or treating: processes – Carbonizing to form article – Agglomeration or accretion
Patent
1992-07-07
1994-03-01
Timm, Catherine
Plastic and nonmetallic article shaping or treating: processes
Carbonizing to form article
Agglomeration or accretion
264522, 219773, 4251748E, 425160, 425DIG13, B29C 3514, B29C 5142
Patent
active
052904903
ABSTRACT:
A method and apparatus for thermoforming 3-dimensional articles of chosen wall thickness dimensions from a polar polymer sheet. The polymer sheet is dielectrically heated, the heating being controlled to impress a predetermined thermal pattern on the sheet. The thermal pattern is selected in accordance with the amount of stretching to which each area of the sheet is subjected during the subsequent work-forming step, the areas subjected to greater stretching being heated to a lower temperature and vice versa. Thus, the stretching action is balanced and results in accurate control of the wall thickness of the final article.
REFERENCES:
patent: 2468697 (1949-04-01), Wiley
patent: 2603741 (1952-07-01), Seifried et al.
patent: 2666951 (1954-01-01), Grove et al.
patent: 2871332 (1959-01-01), Northmore et al.
patent: 3244779 (1966-04-01), Levy et al.
patent: 3244780 (1966-04-01), Levey et al.
patent: 3687594 (1972-08-01), Medendorp
patent: 4088718 (1978-05-01), Mulvany, Jr.
patent: 4165357 (1979-08-01), Vetter
patent: 4234536 (1980-11-01), Thiel et al.
patent: 4396816 (1983-08-01), Krishnakumar
patent: 4409455 (1983-10-01), Belcher et al.
patent: 4420670 (1983-12-01), Croswell et al.
patent: 4476364 (1984-10-01), Prevot et al.
patent: 4619806 (1986-10-01), Gunn
patent: 4842742 (1989-06-01), Plante
patent: 4937021 (1990-06-01), Danforth et al.
Agmund K. Thorsrud, Sensitizing Polymers for Dielectric Heating, date unknown but before Apr. 1989.
Mulcahy and Berns, Thermoforming Takes On More Engineering Applications, (1990), Plastics Engineering 1, 21.
Grimes, Thermoforming (1981-1982), Modern Plastics Encyclopedia, 405.
Chen Alexander T.
Nied Herman F.
General Electric Company
Scanlon Patrick R.
Timm Catherine
Webb II Paul R.
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