Patents by Inventor David Alan Needham

David Alan Needham 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).

  • Inhalation devices
    Patent number: 3995625
    Abstract: A device for providing a gas-air mixture to a patient in response to suction applied by the patient, comprising means defining an air inlet, a backward-facing step, an air passage for directing air past said backward-facing step, a non-return valve for controlling flow of air from said inlet to said air passage and a gas passage communicating with said air passage through at least one orifice adjacent to said backward-facing step.
    Type: Grant
    Filed: October 15, 1974
    Date of Patent: December 7, 1976
    Assignee: Cyprane Limited
    Inventor: David Alan Needham