Patents by Inventor Yasuhiro Iwasa

Yasuhiro Iwasa has filed for patents to protect the following inventions. This listing includes patent applications that are pending as well as patents that have already been granted by the United States Patent and Trademark Office (USPTO).

  • Patent number: 4927069
    Abstract: A soldering method is disclosed as adapted for attaching semiconductor devices such as transistors to their lead mounts. A layer of a solder paste, premixed with rosin flux, is first printed or otherwise formed on each of a series of interconnected semiconductor mounts which may be in the form of a sheet metal punching. The semiconductor devices are placed on the respective solder layers. Then the solder layers are heated to a prescribed temperature higher than both the melting point of the solder and a flux activation temperature at which the flux starts bubbling within the solder. For thus heating the solder layers, the series of semiconductor mounts with the semiconductor devices placed thereon via the solder layers may be fed longitudinally over a suitably heated surface.
    Type: Grant
    Filed: July 10, 1989
    Date of Patent: May 22, 1990
    Assignee: Sanken Electric Co., Ltd.
    Inventors: Takao Ushikubo, Yasuhiro Iwasa, Yukinori Yamaji