Patents by Inventor Douglas P. Simms

Douglas P. Simms 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: 4521239
    Abstract: A particulate substrate provided with a protective coating, comprising particles of a substrate coated with the reaction product of at least one amine compound and a siloxane.
    Type: Grant
    Filed: November 29, 1982
    Date of Patent: June 4, 1985
    Assignee: Mississippi Chemical Corporation
    Inventors: Douglas P. Simms, Joseph M. Dobbs
  • Patent number: 4133918
    Abstract: A non-contacting, non-clogging, electro-mechanically operated marking device or inker for continuous or intermittently marking a semiconductor wafer die is disclosed together with a method of operating the device. The marking device has an ambient pressure ink reservoir within which is mounted a thin, capillary filament guide tube. A length of filament such as, fishline, is positioned within the tube and secured at one end to the plunger of a solenoid. The distal end of the filament is driven out of the capillary tube by the solenoid to force a small amount of the marking fluid or ink out of the reservoir and onto the die without the filament contacting the die. The solenoid coil is energized by a current pulse having a first current level and a second current level that is less than the first current level. The second current level provides a short holding current for the solenoid to prevent spattering of the marking fluid.
    Type: Grant
    Filed: May 16, 1977
    Date of Patent: January 9, 1979
    Assignee: The Computervision Corporation
    Inventors: Douglas P. Simms, Anthony F. White, Carl W. Miller