Plastic article or earthenware shaping or treating: apparatus – Means for molding powdered metal
Reexamination Certificate
2000-10-16
2002-11-26
Silbaugh, Jan H. (Department: 1722)
Plastic article or earthenware shaping or treating: apparatus
Means for molding powdered metal
C425S448000, C406S050000, C406S091000, C406S127000, C141S067000
Reexamination Certificate
active
06485284
ABSTRACT:
BACKGROUND
The invention relates in general to techniques and apparatus for consistently and uniformly transporting and delivering particulate material such as powder. Such transport and delivery systems are used for filling cavities such as in die-casting machines prior to powder compaction in processes for fabricating consolidated parts for automotive, aerospace, micro-electronics, vitamins, pharmaceuticals, and the like.
Particulates such as powder are typically fed from a main hopper and transferred through a tube to a feed or fill shoe which deposits the particulates into the die cavity by gravity or pressure. There are several problems, however, associated with prior art processes for powder delivery and filling of die cavities especially die cavities for high precision, small parts. One such problem is a variation or inconsistency in powder flow in the flexible tube connecting a main hopper or powder supply to a feed shoe on a die surface of a die casting machine. Clumping and surge of the particulates within the flexible tubing and/or the feed shoe also contribute to the non-uniform filling of die cavities. Mechanical shaking of the feed structure above the die cavity can reduce clumping in the powder and improve fill uniformity, but such shaking is not necessarily consistent during successive filling operations. Moreover, such shaking causes segregation of fine materials from coarse materials which results in a loss of uniformity in particle-size distribution and chemical composition.
SUMMARY
Preferred embodiments of the invention provide improved particulate flow and transport during delivery of the particulate materials to structures such as the die cavities of die-casting machines. In one embodiment, the invention includes an improved transport and filling system which employs a gas-control unit.
REFERENCES:
patent: 1759983 (1930-05-01), Houston
patent: 3176369 (1965-04-01), Dennis et al.
patent: 3647333 (1972-03-01), Smith
patent: 3788787 (1974-01-01), Silbereisen et al.
patent: 3832107 (1974-08-01), Cox et al.
patent: 3995771 (1976-12-01), Olivier
patent: 4591324 (1986-05-01), Kubota
patent: 4599215 (1986-07-01), Smarsly et al.
patent: 4841884 (1989-06-01), Engstrom et al.
patent: 4869073 (1989-08-01), Howseman, Jr. et al.
patent: 4970804 (1990-11-01), Hüttlin
patent: 5000624 (1991-03-01), Steiger
patent: 5017754 (1991-05-01), Drouet et al.
patent: 5096096 (1992-03-01), Calaunan
patent: 5143486 (1992-09-01), Geoffroy
patent: 5213816 (1993-05-01), Smyth, Jr. et al.
patent: 5400921 (1995-03-01), Smith, Jr. et al.
patent: 5469994 (1995-11-01), Reh et al.
patent: 5615830 (1997-04-01), Matsunaga et al.
Parrish Phillip A.
Raman Rajkumar
Rowland Roderick
Zahrah Tony F.
Matsys
Millen White Zelano & Branigan P.C.
Nguyen Thu Khanh T.
Silbaugh Jan H.
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