Patents by Inventor David A. Screen

David A. Screen 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).

  • Portable drilling apparatus
    Patent number: 5282704
    Abstract: Portable drilling apparatus provided with a support by means of which it can be secured to a work member and mounting means for a cutting tool including a mounting member having a vertically extending elongate part within which a drive spindle is rotatably mounted, the drive means including an elongate toothed gearwheel driven by a motor held in a fixed position in the support, a toothed gear carried by the drive spindle engaging the elongate gearwheel and sliding axially relative thereto.
    Type: Grant
    Filed: May 22, 1992
    Date of Patent: February 1, 1994
    Assignees: David A. Screen, Michael D. Wooley
    Inventor: David A. Screen