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:
Aug. 05, 1997
Filed:
Nov. 03, 1995
Yoshio Ohzeki, Kawasaki, JP;
Nippon Steel Corporation, Tokyo, JP;
Abstract
A method for efficiently and accurately manufacturing fine metal balls such as solder is provided. A liquid is poured into a vertically elongated cylindrical container, where the liquid is heated up to a temperature higher than the melting point of the metal from its top to middle regions and maintained at a temperature lower than the melting point in the lower region. Metal pieces each of which is made to have a predetermined volume are dropped into the container. The metal pieces are heated and melted while passing the high-temperature region, and take the shape of a substantial sphere due to their own surface tension. However, when the balls reach the low-temperature region, they are cooled and solidified to become substantially perfect metal balls. Since this process can be successively performed, a large number of fine low-melting-point metal balls with high dimensional accuracy can be efficiently manufactured by combining the process with a wire cutter with a high accuracy.