Plastic and nonmetallic article shaping or treating: processes – Mechanical shaping or molding to form or reform shaped article – Forming plural articles
Patent
1989-03-22
1991-06-11
Heitbrink, Jill L.
Plastic and nonmetallic article shaping or treating: processes
Mechanical shaping or molding to form or reform shaped article
Forming plural articles
2643288, 26432811, 425555, 425557, 425562, 425572, 425588, B29C 4512, B29C 4557
Patent
active
050230395
ABSTRACT:
A system and method of controlling hold pressure to cooling cavities when cyclic injection molding a thermoplastic material by utilizing a combination of a multi-parting mold system and an injection unit which together encompass a bifurcated feed system with a molten core. The mold system includes a center part that joins end parts at parting surfaces to define first and second cooling cavities. The feed system is defined by the injection unit and the center part and includes a runner orifice from the injection unit and bifurcated branches. A valve is located in the runner orifice. The first branch feeds injected thermoplastic material to the first cooling cavity, and the second branch feeds injected thermoplastic material to the second cooling cavity. The valve is closed each time after molten thermoplastic material is separately injected under pressure into each of the cooling cavities to hold pressurize the plastic material in the respective cooling cavities. Piston(s) connected to the branches of the feed system may be used for further increasing the hold pressure by protracting the piston and for depressurizing the branches by retracting the piston.
REFERENCES:
patent: 3671162 (1972-06-01), Lohmann
patent: 3707342 (1972-12-01), Lohmann
patent: 3709644 (1973-01-01), Farrell
patent: 3847525 (1974-11-01), Bielfeldt et al.
patent: 4090837 (1978-05-01), Balevski et al.
patent: 4242073 (1980-12-01), Tsuchiya et al.
patent: 4342717 (1982-08-01), Gardner
patent: 4400341 (1983-08-01), Sorensen
patent: 4464327 (1984-08-01), Sorensen
Callan Edward W.
Heitbrink Jill L.
Primtec
LandOfFree
Hold-pressure control in multi-parting injection molding system does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Hold-pressure control in multi-parting injection molding system, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Hold-pressure control in multi-parting injection molding system will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-781498