Patents Assigned to Semi-Tech, Inc.
  • Gradient dyeing of lenses
    Patent number: 3993435
    Abstract: A gradient dyeing machine employing a motor driven threaded camshaft to simultaneously rotate a symmetrical cam of appropriate configuration at the end of the shaft and move a ramp-shaped arm pivotally attached to a threaded carriage riding on the camshaft forward from the motor toward the cam at a continuously increasing angle relative to the camshaft over the surface of the rotating cam, to continuously and repeatedly immerse a lens holder to progressively decreasing depths in a lens coloring liquid.
    Type: Grant
    Filed: February 23, 1976
    Date of Patent: November 23, 1976
    Assignee: Semi-Tech, Inc.
    Inventor: Clayton Paul Korver