The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Sep. 11, 1979
Filed:
May. 17, 1978
Hideto Terada, Toyokawa, JP;
Masanori Yosikawa, Toyokawa, JP;
Sintokogio Ltd., Nagoya, JP;
Abstract
A method for forming a sprue and a communication-hole in a vacuum-sealed mould, and an apparatus for forming the same. This method inlcudes steps of: laying a shield film over a pattern and a sprue forming pattern or a communication hole forming pattern; assembling the pattern with a moulding flask; charging a charged material of particulate type into the moulding flask, and laying another shield film over the moulding flask, the charged material and the top portion of the sprue forming pattern or the communication-hole forming pattern; welding the two films together along the periphery of the top surface of the sprue forming pattern or the communication-hole forming pattern; cutting the two films, thus welded, along the periphery of the top surface of the sprue forming pattern or communication-hole forming pattern; and removing the sprue forming pattern or the communication-hole forming pattern through the cut portion of the film. In addition, there is disclosed an apparatus for welding the two films together and cutting the same along the periphery of the top surface of the sprue forming pattern or the communication-hole forming pattern.