Patents by Inventor Sydney J. Black

Sydney J. Black 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).

  • Line drawing instrument
    Patent number: 4739558
    Abstract: A drawing apparatus is disclosed for guiding the continuous drawing of two intersecting lines with interconnecting curved corner portions. The apparatus comprises a set of rulers which intersect one another at a desired angle of 90.degree. or less to define thereby a corner. A guide is provided for guiding the continuous drawing of two intersecting lines with the curved corner. The guide has a base portion with an external edge. An aperture extends through the base and has an interior edge of a shape to define the desired curved shape for the corner. The guide remains stationary in the corner defined by the rulers to cause a drawing instrument to follow the interior surface of the aperture in continuously drawing a curved corner of desired shape from a first line merging into a second intersecting line.
    Type: Grant
    Filed: April 10, 1986
    Date of Patent: April 26, 1988
    Inventor: Sydney J. Black