Patents by Inventor Anthony H. E. Welch

Anthony H. E. Welch 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).

  • Releasable retaining means and fire door control system
    Patent number: 4237578
    Abstract: Means are provided for retaining fire doors in the open position against the action of spring or other automatic door closers, with remote control release which can be actuated if a fire is detected. In use, one part thereof is mounted on the wall and has holding means for engagement with another part which is mounted on the door. The wall mounted part also includes pneumatically operated actuating means for actuating the holding means when a gas pressure differing from atmospheric pressure is applied thereto so that the door is released when such pressure is removed. The pneumatically operated actuating means of a number of such door holders may be connected to a common gas pressure source together with means for releasing the gas pressure on occurrence of a fire.
    Type: Grant
    Filed: August 25, 1978
    Date of Patent: December 9, 1980
    Assignee: Dorgard Limited
    Inventor: Anthony H. E. Welch