Patents by Inventor Charles Hallstrom

Charles Hallstrom 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: 4144918
    Abstract: A mobile tree harvester includes a shear mounted at the base of a harvesting frame for shearing a tree trunk, a grip arm pivotably mounted to the frame above the shear for gripping the tree trunk, delimbers mounted above the grip arms for removing branches from the trunk, and an endless tract mounted on each grip arm for propelling the tree trunk along the forward frame. Lift arms pivotably couple the forward frame to a main body of a wheeled vehicle. A sway mechanism is coupled to both lift arms to provide for relative movement of one lift arm with respect to the other such that the harvesting frame can sway from the vertical position in a left or right direction. A tilt mechanism is coupled to the harvesting frame, lift arm, and main body to maintain the frame in its vertical ground position as the lift arms lift the frame off the ground. The tilt mechanism also tilts the frame about an axis transverse to the vehicle axis to a horizontal position such that the sheared end of the tree trunk faces rearwardly.
    Type: Grant
    Filed: September 6, 1977
    Date of Patent: March 20, 1979
    Inventor: Charles A. Hallstrom