Patents by Inventor Lowell B. Campbell

Lowell B. Campbell 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).

  • Patent number: 5078922
    Abstract: An improved bubbler has walls formed of thin stainless steel. A hollow cylindrical body member forms a cylindrical sidewall and has welded to it a top end cap and a bottom end cap. A horizontally disposed sparger tube is connected to the carrier-gas inlet tube and is positioned within the bubbler chamber adjacent to the bottom end cap. The sparger tube has a plurality of horizontally spaced-apart exit holes formed therein for providing a plurality of carrier-gas streams into the liquid chemical. The carrier gas bubbles up through the liquid chemical, causing the liquid chemical to vaporize and diffuse into the carrier gas. A substantially uniform temperature throughout the chemical liquid is provided with a heat-conductive enclosure formed of aluminum plates which are thicker than the walls of the bubbler chamber and which contact and entirely surround the exterior surface of the stainless steel bubbler chamber.
    Type: Grant
    Filed: October 22, 1990
    Date of Patent: January 7, 1992
    Assignee: Watkins-Johnson Company
    Inventors: Craig C. Collins, Michael A. Richie, Fred F. Walker, Brian C. Goodrich, Lowell B. Campbell