Patents by Inventor Heinrich Hagendorn

Heinrich Hagendorn 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).

  • Hydraulic positioner for valves
    Patent number: 4103864
    Abstract: A positioner having a differential piston which is hydraulically locked by the oil pressure of a tripout valve and which in turn cocks a closing and an opening spring against each other, in which, after the tripout oil pressure falls, the closing spring is first released, pulling the piston up, thereby permitting the opening spring to open the valve suddenly.
    Type: Grant
    Filed: December 27, 1976
    Date of Patent: August 1, 1978
    Assignee: Siemens Aktiengesellschaft
    Inventor: Heinrich Hagendorn