Patents by Inventor Henry L. Roxburgh

Henry L. Roxburgh 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).

  • Gas mixing apparatus
    Patent number: 4148311
    Abstract: Apparatus for supplying a mixture of oxygen and air for respiratory purposes and comprising a supply regulator having a first chamber with an inlet and an outlet for oxygen and a second chamber with an inlet and an outlet for air, control means responsive to a higher pressure in said first than said second chambers to permit air to enter said second chamber, adjustment means for modifying the action of said control means, first and second restrictors in the first and second outlets respectively, the second restrictor bore being larger than that of the first, said first and second outlets leading to a common supply duct and then to a first demand regulator responsive to an inspiration pressure drop to permit a flow of gas therethrough.
    Type: Grant
    Filed: May 18, 1977
    Date of Patent: April 10, 1979
    Assignee: The Secretary of State for Defence in Her Britannic Majesty's Government of the United Kingdom of Great Britain and Northern Ireland
    Inventors: Richard C. London, Alexander J. F. MacMillan, Henry L. Roxburgh