Patents by Inventor Donald F. Ball

Donald F. Ball 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).

  • Apparatus for controlled spray etching
    Patent number: 5290384
    Abstract: An apparatus is provided for controlled spray etching, in which panels, such as printed circuit boards are delivered through an etching chamber, to have a spray etchant sprayed generally on upper and lower surfaces of the panel. The spray is controlled such that a reduced amount of etchant is provided on the perimeter surface portions of the panel, relative to the central surface portions of the panel, transversely of the path of travel of the panels through the etching chamber. The spray may be varied in amount, preferably by varying the pressure at different locations transversely of the chamber; the spray longitudinally through the chamber, may vary, to spray leading and trailing surface portions of the panels a lesser amount than central portions of the panels, measured longitudinally. The control of the spray of leading and trailing surface portions of the panels may be facilitated by one or more sensors that control an intermittent discharge of spray etchant near the inlet to the etch chamber.
    Type: Grant
    Filed: May 12, 1993
    Date of Patent: March 1, 1994
    Assignee: Chemcut Corporation
    Inventors: Karl F. G. Ketelhohn, Donald F. Ball
  • Method and apparatus for controlled spray etching
    Patent number: 5228949
    Abstract: A method and apparatus is provided for controlled spray etching, in which panels, such as printed circuit boards are delivered through an etching chamber, to have a spray etchant sprayed generally on upper and lower surfaces of the panel. The spray is controlled such that a reduced amount of etchant is provided on the perimeter surface portions of the panel, relative to the central surface portions of the panel, transversely of the path of travel of the panels through the etching chamber. The spray may be varied in amount, preferably by varying the pressure at different locations transversely of the chamber; the spray longitudinally through the chamber, may vary, to spray leading and trailing surface portions of the panels a lesser amount than central portions of the panels, measured longitudinally. The control of the spray of leading and trailing surface portions of the panels may be facilitated by one or more sensors that control an intermittent discharge of spray etchant near the inlet to the etch chamber.
    Type: Grant
    Filed: November 7, 1991
    Date of Patent: July 20, 1993
    Assignee: Chemcut Corporation
    Inventors: Karl F. G. Ketelhohn, Donald F. Ball