Patents by Inventor David Derby

David Derby 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).

  • Publication number: 20070072713
    Abstract: A dual backlash tensioner includes a support having a recess therein. A plunger is slidable in the recess and includes a shoe extending outward from the recess. A first resilient member acts between the support and the plunger and urges the shoe outwardly. An oscillatable stop cam having first and second teeth spacedly disposed thereon is engagable with the plunger. The stop cam is pivotally mounted on the support. A second resilient member urges the first tooth toward engagement with the plunger. The plunger has a control portion opposing the stop cam that includes a toothed rack and an adjoining depression positioned toward the shoe.
    Type: Application
    Filed: September 23, 2005
    Publication date: March 29, 2007
    Inventors: Thomas Slopsema, David Derby