Patents by Inventor Darryll Arthur Douglas Holland

Darryll Arthur Douglas Holland 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).

  • Vented port-cap for fire hydrant
    Patent number: 7278442
    Abstract: The vented port-cap includes a check-valve, which admits air into the barrel of the hydrant when the pressure inside is lower than the pressure outside. After an inspection of the hydrant, the hydrant can be left to drain by itself, even though the port-cap has been replaced and tightened.
    Type: Grant
    Filed: August 31, 2005
    Date of Patent: October 9, 2007
    Inventors: Darryll Arthur Douglas Holland, Sean Kellie Montgomery