Patents by Inventor Herrmann Irresberger

Herrmann Irresberger 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).

  • Method for controlling a hydraulically operated mine roof support and an arrangement for carrying out the method
    Patent number: 4264237
    Abstract: A method of operating a hydraulically expandable and collapsable prop of a mine roof support in which the cylinder space of the prop below the piston therein normally communicates with an overpressure valve adjusted to a pressure equal to the setting pressure of the prop, wherein the method comprises the steps of interrupting communication of the overpressure valve with the cylinder space of the prop while the latter is expanded and restoring the communication when the prop is pressed against the mine roof while the cylinder space is disconnected from the hydraulic pressure circuit and an arrangement for carrying out the method.
    Type: Grant
    Filed: July 10, 1979
    Date of Patent: April 28, 1981
    Assignee: Bergwerksverband GmbH
    Inventors: Herrmann Irresberger, Friedrich Graawe