Patents by Inventor John F. Krueck

John F. Krueck 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).

  • Patent number: 4367673
    Abstract: A multi-purpose lifting vehicle includes a hydraulic cylinder for controlling the elevation of a boom hoist device operably connected thereto. The device is alternately used in crane or front end loader modes of operation. The vehicle includes a hydraulic system for controlling the operation of the cylinder comprising a multi-position mode selector valve for selecting the specific mode of operation of the boom hoist device for raising, lowering and enabling the boom hoist device to float. The control system further includes a holding valve for locking the hydraulic fluid within the raising end of the cylinder for maintaining the elevation of the boom hoist device. A first bypass circuit is provided about the holding valve for enabling fluid to escape from the raising end of the cylinder while fluid is simultaneously flowing to the lowering end thereof.
    Type: Grant
    Filed: January 9, 1981
    Date of Patent: January 11, 1983
    Assignee: Dresser Industries, Inc.
    Inventors: John F. Krueck, Donald G. Braden, William J. Askins
  • Patent number: D276758
    Type: Grant
    Filed: October 14, 1980
    Date of Patent: December 11, 1984
    Assignee: Dresser Industries, Inc.
    Inventors: John F. Krueck, Gregg M. Davis