Patents by Inventor Harald Wittrich

Harald Wittrich 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: 5193739
    Abstract: In the process according to the invention for soldering electronic boards, in particular, printed circuit boards with devices installed on them, first, during the pickling process, a condensable process material, for example, water, is introduced into flaws in the oxide layers on the soldering connection surfaces and at least partially condensed in the flaws. Then, the oxide layers are exposed to rapid heating such that the process material condensed in the flaws vaporizes explosively and thus the oxide layer breaks up and cracks off of the basis material, such that the soldering connection surfaces for the subsequent actual soldering process are brought to virgin condition. In the case of wave soldering, the rapid heating occurs preferably by means of the wave of solder itself. If non-oxide passive layers must also be removed, this occurs preferably in a preceding stage of the pickling process, during which the oxide layer is hydrophilized. For this, a plasma pretreatment is suitable.
    Type: Grant
    Filed: December 18, 1991
    Date of Patent: March 16, 1993
    Assignee: WLS Karl-Heinz Grasmann
    Inventors: Volker Liedke, Karl-Heinz Grasmann, Hans-Jurgen Albrecht, Harald Wittrich, Wilfred John, Wolfgang Scheel
  • Patent number: 5192582
    Abstract: The invention is directed to a procedure for processing joints to be soldered, preferably printed circuit boards fitted with electric components, and an arrangement for executing this procedure, wherein the joints are subjected to plasma treatment before the soldering process. The joints may be subjected to plasma treatment separately or in the relative position necessary for the soldering process.
    Type: Grant
    Filed: November 5, 1990
    Date of Patent: March 9, 1993
    Assignee: WLS Karl-Heinz Grasmann Weichlotanlagen-und Service
    Inventors: Volker Liedke, Karl H. Grasmann, Hans-Jurgen Albrecht, Harald Wittrich, Wilfred John, Wolfgang Scheel