Patents by Inventor Robert E. Lietz

Robert E. Lietz 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: 6508972
    Abstract: An efficient process is described for making rubber tube segments, such as lathe-cut gaskets or conveyor roller covers, by cross-head extrusion of uncured rubber onto an axially aligned string of mandrels. Each mandrel in the string is separated from its two neighbors by respective spacers. The outer diameter of the extruded tube is kept within precise tolerances by making a non-contact measurement of the outer diameter at the output from the extruder and using the measured diameter to control the extrusion process. The extruded tube is cut into segments by a cutter that acts responsive to a spacer sensor and that makes the cuts between the mandrels. In one version, the extruded tube is conveyed through a curing oven by apparatus that only contacts and supports the tube adjacent ones of the spacers.
    Type: Grant
    Filed: March 6, 2000
    Date of Patent: January 21, 2003
    Inventor: Robert E. Lietz