| 摘要 |
PURPOSE:To excavate a trench with an accurate gradient, by a method wherein a running distance responding to a detecting elevation amount of a ground working machine is outputted by a control pattern, and the elevating mechanism of the working machine is controlled so that the output value is coincident with an actual running distance. CONSTITUTION:When a trench for drainage is excavated by a ground working machine, e.g., trenchers, a pulse is generated by an encoder 13 in proportion to a vehicle shaft 12 of a tractor, and an adding counter 14 counts a pulse to output a signal, responding to a running distance to a comparing panel 24. Meanwhile, a slider 19a of a potentiometer 20 is rotated in linkage with a shaft 21 of the lift arm of the ground machine, and a control pattern for a distance responding to an elevating amount is fed to the comparing panel 24. An output from the adding counter 14 is compared with an output from a con trol pattern generating part 17 by the comparing panel 24, and a hydraulic elevating mechanism 6 causes elevation of the ground machine so that the two outputs are coincident with each other. |
