Patents by Inventor Derrold D. Johnson

Derrold D. Johnson 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).

  • Programmed test tube rack for manually performing medical diagnostic assays
    Patent number: 3948606
    Abstract: A test tube rack having columns and rows for manually performing medical diagnostic assays which require various sequential operations. The top face of the rack has indicia such as color strips and written directions to provide a program of operations which is to be followed in a particular assay. The individual test tubes are manually progressed in columns from row to row as the programmed sequence of operations is carried out. The top face may be replaced by other top plates programmed for other different assays.
    Type: Grant
    Filed: January 26, 1973
    Date of Patent: April 6, 1976
    Inventor: Derrold D. Johnson