Plastic and nonmetallic article shaping or treating: processes – Direct application of fluid pressure differential to... – With internal application of fluid pressure
Patent
1987-11-17
1990-06-19
Thurlow, Jeffery
Plastic and nonmetallic article shaping or treating: processes
Direct application of fluid pressure differential to...
With internal application of fluid pressure
2643281, 26432813, 425812, B29C 4500, B29C 4534, B29D 2200
Patent
active
049351915
ABSTRACT:
A process for producing an injection molded product includes introducing a stream of plastic material into a mold space at a first pressure. A quantity of gas is stored in a storage chamber at a second pressure which is at least as high as the first pressure. The gas is introduced into the molten stream of plastic material immediately after the molten material has passed the position at which the gas is introduced thereby forming a gas cavity in the molten material. The gas exerts pressure on the surrounding plastic material to urge the material toward the surfaces of the mold space. As the feeding of the plastic material into the mold space continues, the injection of the gas is also continued. The supply of molten material is terminated when the surfaces of the mold space are completely covered by the molten material. A pressure is held within the gas cavity as the plastic material cools. Subsequently, the pressure is released to bring the gas cavity to ambient pressure. Then the mold is opened to remove the hollow shaped article. An apparatus for producing an injection molded product is also disclosed.
REFERENCES:
patent: 2331688 (1943-10-01), Hobson
patent: 2345144 (1944-03-01), Opavsky
patent: 3021559 (1962-02-01), Strong
patent: 3135640 (1964-06-01), Kepka et al.
patent: 3288898 (1966-11-01), West
patent: 4033710 (1977-07-01), Hanning
patent: 4043715 (1977-08-01), Hendry
patent: 4067673 (1978-01-01), Hendry
patent: 4082226 (1978-04-01), Appleman
patent: 4101617 (1978-07-01), Friedrich
patent: 4106887 (1978-08-01), Yasuike et al.
patent: 4120924 (1978-10-01), Rainville
patent: 4129635 (1978-12-01), Yasuike et al.
patent: 4136220 (1979-01-01), Olabisi
patent: 4140672 (1979-02-01), Kataoka
patent: 4234642 (1980-11-01), Olabisi
patent: 4247515 (1981-01-01), Olabisi
patent: 4390332 (1983-06-01), Hendry
patent: 4474717 (1984-10-01), Hendry
patent: 4488863 (1984-12-01), Collette
patent: 4555225 (1985-11-01), Hendry
patent: 4601870 (1986-07-01), Sasaki
patent: 4824732 (1989-04-01), Hendry et al.
patent: 4855094 (1989-08-01), Hendry
Mar. 1980 Modern Plasatics article entitled "Through-the-Nozzle Gas Injection Produces Class-A Foam Parts".
June 1985 European Plastics News article entitled "Advanced Injection Molding Process".
Dec. 9, 1982 Machine Design article entitled "The Best of Two Worlds in Plastics Processing".
June 1985 Eureka Transfers Technology article entitled "Gas Relieves Moulding Stresses".
Johnson Thomas W.
Tentoni Leo B.
Thurlow Jeffery
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