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:
Apr. 11, 1995
Filed:
Jun. 21, 1994
Toyota Jidosha Kabushiki Kaisha, Toyota, JP;
Abstract
In a vacuum casting method, a mold cavity is reduced in pressure to a vacuum, and when a gate is opened, a molten metal which has been raised to a molten metal retaining dome is charged into the cavity at a high speed. When a portion of a molten metal held in a molten metal holding furnace is raised to the molten metal retaining dome, an upper surface of the molten metal is moved downwardly and upwardly through at least one cycle in the molten metal retaining dome, or a swirl flow is generated in the molten metal in a stalk. Such a unique motion as the downward and upward motion or the swirl flow effectively operates to detach solid metal pieces from an inside surface of the molten metal retaining dome or the stalk to push them to an upper portion of the molten metal. As a result, the detached metal pieces are prevented from being charged into the mold cavity to thereby cause defects in a cast product.