Abstract: The control system is provided with a detector that detects whether the ripper is operated in a piercing operating mode or a digging operating mode. In the piercing operating mode the angle of the shank is adjusted to a preset piercing angle, while in the digging operating mode the shank angle is adjusted to a preset digging angle thereby effecting optimum piercing and digging operations. Limit switches for detecting upper and lower limit positions of the shank are provided for raising and lowering the shank between these limit positions while adjusting the shank angle. Further an overload detector is provided for raising the shank when its load exceeds a predetermined load and lowering the shank when the load decreases below it. A manual preference control device also provided for enabling manual control during automatic control.

Abstract: An automatic control system for a ripper used on a construction equipment in which a load detector is provided on the ripper for detecting load acting on the ripper shank and lift cylinders are actuated to automatically raise the shank when overload is applied to the shank during ripping operation. The ripper is also provided with a depth detector for detecting upper and lower limit positions of the shank and the vertical movement of the shank can be limited between the upper and lower limits. When no overload is applied, the shank is maintained at the lower limit position to rip the ground at a predetermined penetration depth.