Plastic and nonmetallic article shaping or treating: processes – With measuring – testing – or inspecting
Patent
1995-11-21
1998-03-17
Heitbrink, Jill L.
Plastic and nonmetallic article shaping or treating: processes
With measuring, testing, or inspecting
264 403, 264 51, 264 85, 264572, 2643281, 26432813, 425 4R, 425146, 425546, B29C 4534
Patent
active
057283290
ABSTRACT:
A method of injection molding for use with an injection molding machine includes: a) generating pressurized gas and pressurized moisture within molten plastic as plastic pellets are plasticized in the injection molding machine, the pressurized gas and the pressurized moisture having a total pressure defining an internal counterpressure within the molten plastic; (b) pressuring air within a cavity of a mold in the injection molding machine to an air pressure level which is substantially equal to the internal counterpressure in order to counterbalance the internal counterpressure as the molten plastic is injected into the cavity, thus providing a substantially pressure balanced molding environment for the plastic; and (c) maintaining the air pressure level in the cavity substantially constant as the molten plastic is injected into the cavity. A mold apparatus for use with the method of injection molding includes selectively sealed venting of the mold cavity, the vents being configured to maintain a substantially constant air pressure within the cavity as the cavity is filled with molten plastic.
REFERENCES:
patent: 3532154 (1970-10-01), Balevski
patent: 3632703 (1972-01-01), Sullivan et al.
patent: 3694529 (1972-09-01), Josephsen et al.
patent: 3819313 (1974-06-01), Josephsen et al.
patent: 3893792 (1975-07-01), Laczko
patent: 3988403 (1976-10-01), Angell, Jr. et al.
patent: 4092385 (1978-05-01), Balevski et al.
patent: 4153231 (1979-05-01), Hayakawa et al.
patent: 4288398 (1981-09-01), Lemelson
patent: 4312820 (1982-01-01), Arnold et al.
patent: 4318874 (1982-03-01), Lemelson
patent: 4636084 (1987-01-01), Kopernicky
patent: 4750409 (1988-06-01), Hendry
patent: 4852028 (1989-07-01), Korpela et al.
patent: 4943407 (1990-07-01), Hendry
patent: 5098637 (1992-03-01), Hendry
patent: 5264163 (1993-11-01), Lemelson
patent: 5441680 (1995-08-01), Guergov
patent: 5482669 (1996-01-01), Shah
patent: 5558824 (1996-09-01), Shah et al.
patent: 5566743 (1996-10-01), Guergov
"Investigation of Processing-Structure-Property Relationships in Structural Foam Molding", Alex W. Kawczak & Duane Krueger, The Dow Chemical Company, pp. 67-78, date unknown.
"Injection Molding: Gas Counter Pressure Process", Integral/Structural Polymer Foams, Editors: G. Henrici-Olive and S. Olive; English by F.A. Shutov, 1986, pp. 71-74.
"New Advancements in Counterpressure Structural Foam Processing", Michael Caropreso Typical Clamp Requirements, pp. 79-81, 1984.
International Preliminary Examining Authority, "Written Opinion", Mar. 15, 1996, 3 pages, Claim 1-9.
International Searching Authority, "Notification of Transmittal of the International Search Report or the Declaration", Apr. 9, 1996, 4 pages, Claims 1-4.
Pamphlet: "TM Process -- Injection Molding Of Structural Foam", Date Unknown Derwent Patent Search.
LandOfFree
Method and apparatus for injecting a molten material into a mold does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Method and apparatus for injecting a molten material into a mold, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Method and apparatus for injecting a molten material into a mold will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-955014