Concurrent Adjustment Patents (Class 172/660)
  • Patent number: 4167978
    Abstract: Four or more cultivator arms or shanks are pivoted to the front and rear of a main frame and are interconnected by linkage so that if a cultivator blade on one arm strikes an obstruction, then it moves rearwardly to clear same and at the same time the others that are interconnected, move forwardly by a lesser amount thus absorbing the movement of the cultivator blade striking the obstruction. When the obstruction is passed, the engagement of the remaining blades with the ground, returns them to the original position thus returning the tripped blade to the original position.
    Type: Grant
    Filed: November 11, 1977
    Date of Patent: September 18, 1979
    Inventor: Harold A. Kirchner