GRADE TRIMMER

摘要

GRADE TRIMMER A grade cutting machine having an alongated main frame supported on three bogey-mounted individually driven endless tracks. The cutting tool is rotatably mounted on an axis transverse the front of the main frame within an enclosing bowl. A vertically adjustable moldboard is provided across the back wall of the bowl behind the cutting tool. Two of the endless tracks are mounted on vertical non-rotatable axes on opposite sides of the main frame behind the moldboard and each is provided with an extensible framesupporting member for automatic simultaneous or independent vertical adjustment. The third endless track which can control the steering under certain conditions is provided with an extensible frame-sup-porting member connected for independent manually controlled vertical adjustment. In one embodiment the drive means for the front pair of endless tracks are under the control of the steering function of the rear endless track so that, as a steering correction is made, the front endless track on theoutside of the curve is driven faster while the front endless track on the inside of the curve is driven slower, the speed differences being inversely proportional to the radius of the curve being negotiated. A conveyor having a pivotal rear section under the control of dual rams through dual levers for deposit of the cuttings anywhere in a 180.degree. arc is provided. The moldboard is under the control of a pair of rams and carries both the grade sensor and the slope pendulum control whereby slope corrections are isolated from grade corrections.