Plastic article or earthenware shaping or treating: apparatus – Female mold and charger to supply fluent stock under... – With means to close mold
Reexamination Certificate
1999-03-23
2001-07-03
Mackey, James P. (Department: 1722)
Plastic article or earthenware shaping or treating: apparatus
Female mold and charger to supply fluent stock under...
With means to close mold
C425S451200, C425S451700, C425S595000
Reexamination Certificate
active
06254378
ABSTRACT:
BACKGROUND OF THE INVENTION
In the electronics manufacturing industry, a high degree of cleanliness is required to prevent contamination of circuitry and devices, which may cause subsequent electronic failure. A common way of packaging electronic integrated circuits is by encapsulating the prefabricated integrated circuit and a portion of the attached leadframe in a plastics material. Typically this is performed utilising injection molding apparatus, often of the transfer mold variety. Known injection molding equipment employs hydraulic presses, and it is not uncommon for hydraulic fluids to leak from the hydraulic presses, which may contaminate the molds and molded products. Although cleansing of the molds is performed regularly, the cleaning techniques are not always effective in removing contaminating debris from the molds. Furthermore, removal of molds for cleaning is often difficult and time consuming. It is an object of the present invention to overcome these problems.
BRIEF SUMMARY OF THE INVENTION
Accordingly the present invention provides an injection molding apparatus, comprising a molding press adapted to receive a mold having a cavity shaped for the formation of a molding product, the molding apparatus comprising: first and second platens which are movable relative to one another so as to allow respective mold parts mounted thereon to be moved between open and closed configurations; and
an electro-pneumatic drive mechanism comprising: a threaded screw member coupled to one of the first and second platens; an electric motor coupled to drive the threaded screw member by way of a gear mechanism for moving the first and second platens relative to one another; and a pneumatic cylinder mechanism for driving the screw thread of the threaded member separately from said electric motor.
The present invention is particularly well adapted for use in an integrated circuit encapsulation process.
Preferably, the mold is provided with a spring-loaded bearing system for easy removal of the mold from the press.
REFERENCES:
patent: 4332537 (1982-06-01), Slepcevic
patent: 4480975 (1984-11-01), Plummer et al.
patent: 4575328 (1986-03-01), Fierkens et al.
patent: 4687431 (1987-08-01), Stengelin
patent: 4968239 (1990-11-01), Inaba et al.
patent: 5053172 (1991-10-01), Yamasaki et al.
patent: 5378140 (1995-01-01), Asano et al.
patent: 5622737 (1997-04-01), Hehl
patent: 5698240 (1997-12-01), Haguchi
Burns Doane Swecker & Mathis L.L.P.
Fastech Systems (S) Pte Ltd.
Mackey James P.
LandOfFree
Injection molding apparatus does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Injection molding apparatus, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Injection molding apparatus will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2504819