Method for forming vacuum-sealed mould
US4167206A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | May 17, 1978 |
| Grant date | Sep 11, 1979 |
| Priority date | — |
| Expiry date | May 17, 1998 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T83/293
- WIPO fieldMaterials, metallurgy
- WIPO sectorChemistry
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.