Patents by Inventor Edgar R. Johnson

Edgar R. 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).

  • Pitcher's circle compass
    Patent number: 10639928
    Abstract: The invention is an apparatus and method for marking a pitcher's circle for a sport such as girl's fast pitch softball. A spike locates the center of the circle and a cord attached to the spike defines the radius of the circle. A scribe attached to a handle and to the cord is configured to mark the dirt. The scribe defines a marking tip and an indicator portion. The marking tip leaves a track in the dirt that is within a track left by the indicator portion when the handle is in the proper vertical position.
    Type: Grant
    Filed: May 23, 2018
    Date of Patent: May 5, 2020
    Inventor: Edgar R Johnson
  • Vent cleaning system
    Patent number: 4792363
    Abstract: A vent cleaning system for removing dust from a vent has a brush that substantially occludes the vent, and is rotated by a flexible shaft that is concentrically disposed in a flexible tubular vacuum conduit, so that dust is dislodged from the vent wall and vacuumed into the vacuum conduit.
    Type: Grant
    Filed: February 1, 1988
    Date of Patent: December 20, 1988
    Inventors: Smead P. Franklin, Jr., Edgar R. Johnson