Patents by Inventor Walter F. Ahlberg

Walter F. Ahlberg 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).

  • Multi-purpose rotating membrane filter
    Patent number: 5073262
    Abstract: A Multi-Purpose Rotating filter comprising a multiplicity of controlled pore sized membrane covered hollow double cone shaped filter discs mounted on a rotatable hollow shaft with provisions for feed between the rotating discs and disc speed sufficient to create a boundary layer to keep the disc surfaces essentially clean as disclosed.
    Type: Grant
    Filed: February 14, 1990
    Date of Patent: December 17, 1991
    Inventors: Walter F. Ahlberg, Joseph F. Long
  • Multi-purpose rotating membrane filter
    Patent number: 4925557
    Abstract: A multi-purpose rotating membrane filter unit wherein the central portion of hollow filter discs covered with controlled pore size membranes communicate with the interior of the hollow rotating mounting shaft with the membrane surface of the rotating disc being kept clean by speed of rotation and, in some cases intermittent back flushing, and with filtrate draw off thru the hollow rotating mounting shaft.
    Type: Grant
    Filed: April 14, 1989
    Date of Patent: May 15, 1990
    Inventors: Walter F. Ahlberg, Jr., Joseph F. Long