Plastic and nonmetallic article shaping or treating: processes – Direct application of fluid pressure differential to... – With internal application of fluid pressure
Patent
1988-09-23
1990-05-08
Thurlow, Jeffery
Plastic and nonmetallic article shaping or treating: processes
Direct application of fluid pressure differential to...
With internal application of fluid pressure
264102, 264154, 2643281, 2643288, 425546, 425547, 425567, 425812, 425DIG58, B29C 4500, B29C 4534, B29D 2200
Patent
active
049236679
ABSTRACT:
An injection molded plastic article is produced by introducing a stream of molten plastic material from an injection molding machine cylinder into an article forming mold space. Pressurized gas is supplied into the interior of the molten plastic material to form a gas containing cavity therein. The plastic material is then allowed to solidify and cool sufficiently so that the article can itself sustain the form dictated by the mold surface. The cavity is vented to reduce the pressure within the cavity to ambient pressure prior to opening of the mold. The step of venting the cavity is achieved by providing at least one position which is separate from the plastic inlet and the gas inlet a vent passage in the mold open at its inner end to a part of the interior of the mold at which the gas containing cavity is formed, and a retractable closure for opening and closing the vent passage at its inner end, maintaining the closure in its closed position during the forming of the article whereby the cavity wall is formed over the inner end of the vent passage and the closure therefor, and subsequently retracting the closure to allow the creation of a vent opening in the cavity wall in the area of the inner end of the vent passage through which vent opening gas from the cavity passes into the vent passage. Apparatus for carrying out the above process is also described.
REFERENCES:
patent: 2105704 (1938-01-01), Shippy
patent: 2331688 (1943-10-01), Hobson
patent: 3021559 (1962-02-01), Strong
patent: 3114931 (1963-12-01), Pelikan
patent: 3358062 (1967-12-01), Lemelson
patent: 3366993 (1968-02-01), Lemelson
patent: 3378612 (1968-04-01), Dietz
patent: 3575949 (1971-04-01), Humphrey
patent: 3793415 (1974-02-01), Smith
patent: 3793421 (1974-02-01), Paubandt
patent: 3873661 (1975-03-01), Kontz
patent: 3899278 (1975-08-01), Fead et al.
patent: 4017225 (1977-04-01), Hanning
patent: 4033710 (1977-07-01), Hanning
patent: 4070429 (1978-01-01), Uhlig
patent: 4101617 (1978-07-01), Friederich
patent: 4115491 (1978-09-01), Hanning
patent: 4129635 (1978-12-01), Yasuike et al.
patent: 4136220 (1979-01-01), Olabisi
patent: 4140672 (1979-02-01), Kataoka
patent: 4201742 (1980-05-01), Hendry
patent: 4234642 (1980-11-01), Olabisi
patent: 4247515 (1981-01-01), Olabisi
patent: 4389358 (1983-06-01), Hendry
patent: 4474717 (1984-10-01), Hendry
patent: 4498860 (1985-02-01), Gahan
patent: 4555225 (1985-11-01), Hendry
patent: 4740150 (1988-04-01), Sayer
Plastics Technology, Swirl-Free Foam Parts, May 1976, pp. 33-36, Union Carbide.
Engineering & Processing News, Through-the-Nozzle Gas Injection Produces Class A Foam Parts, Mar. 1980, pp. 22-24, Asahi-Dow.
Machine Design, The Best of Two Worlds in Plastic Processing, Dec. 9, 1982, pp. 99-102.
Eureka Transfers Technology, Gas Injection Relieves Moulding Stresses, Jun. 1985, p. 31.
Plastics Machinery and Equipment, Gas-Cored Injection Techniques Go Into Production, Nov. 1985, p. 24.
Plastics Technology, New Automotive PP, HDPE Applications Tested in Europe, Nov. 1985, p. 106.
Modern Plastics, Process Molds Rigid, Smooth Parts that are Stress Free, Nov. 1985, p. 26.
British Newspaper Article, Plastics After Deal Clinched, by John Baker, sometime prior to Oct. 1, 1985.
Applied Technology, Plastic Moulding Process Give More Design Freedom, single page, sometime in or before 1985.
Moulding System with Body Appeal, undated, source unknown.
Cinpres Presentation Summary Brochure, Controlled Internal Pressure Process ("CINPRES"), Sep./Oct. 1985.
Cinpress Brochure, Cost Saving with Cinpres.
European Plastics News, Advanced Injection Moulding Process, Jun. 1985.
Plastics & Rubber Weekly, New Foam Process Hybrid is `Biggest Boon Since Screw', Apr. 27, 1985, p. 18.
Cinpres News, Aug. 1987.
Hoechst Plastics, Injection Moulding of Thermoplastics, Dec. 1972.
Netstal, Setting Up for Injection, Feb. 1973.
Three CINPRES Sales Pamphlets.
Cinpres Limited
Tentoni Leo B.
Thurlow Jeffery
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