Patents by Inventor David Brian Letch

David Brian Letch 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).

  • Induced draft furnace air addition method and apparatus
    Patent number: 5795148
    Abstract: Method and apparatus for maintaining even heat distribution to each of the tubes contained in a down-fired induced draft furnace by eliminating external atmosphere disturbances such as wind from influencing furnace operation. The top of the furnace is isolated from receiving ambient air except through a central path which controls both rate and direction of air flow.
    Type: Grant
    Filed: March 12, 1996
    Date of Patent: August 18, 1998
    Assignee: Air Products and Chemicals, Inc.
    Inventors: Stephen Paul DiMartino, Sr., Peter George Goldstone, David Brian Letch, Nasim Hassan Malik