Patents by Inventor Christiaan J. Rauwendaal

Christiaan J. Rauwendaal 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).

  • Extruder screw
    Patent number: 4798473
    Abstract: An extruder screw designed to operate in a continuous diameter barrel-type housing having a variable flight width, helix angle and radical clearance along the length of the extruder screw to reduce extruder screw induced power consumption and stock temperature generation in the manufacture of linear low density polyethylene plastics.
    Type: Grant
    Filed: February 15, 1985
    Date of Patent: January 17, 1989
    Inventor: Christiaan J. Rauwendaal
  • Method of preparing a piezoelectric device
    Patent number: 4688306
    Abstract: A piezoelectric device comprising a first conductor, a conductive polymer member which contacts the first conductor, a piezoelectric polymer member which contacts the conductive polymer member but which is separated from the first conductor and which has been rendered piezoelectric by stretching and polarizing it while it is in contact with the conductive polymer member, and a second conductor which contacts the piezoelectric polymer member but which is separated from both the conductive polymer and the first conductor.
    Type: Grant
    Filed: September 11, 1986
    Date of Patent: August 25, 1987
    Assignee: Raychem Corporation
    Inventors: Pravin L. Soni, Nigel R. Farrar, Peter Turk, Christiaan J. Rauwendaal
  • Extrusion apparatus
    Patent number: 4129386
    Abstract: A new extruder screw design incorporating an optimal flight helix angle and flight height in the feed section and metering section and a constantly varying helix angle with a constantly decreasing flight height in the transition section is disclosed; the screw being efficiently fed by use of a grooved section of extruder barrel in the area of the feed section.
    Type: Grant
    Filed: June 29, 1977
    Date of Patent: December 12, 1978
    Assignee: Akzona Incorporated
    Inventor: Christiaan J. Rauwendaal