| 摘要 |
PURPOSE:To make it possible to take in relatively large sized gravel, etc. and to crush the gravel, etc., taken in with low driving force. CONSTITUTION:Expansive operation of cylinder rods 50A, 52A and 54A of hydraulic cylinders 50, 52 and 54 is controlled by a hydraulic controller 56, a head 28 is oscillated in a shoe 26, and a caliber L taken in gravel 88, etc., such as a space between the front end top 44 of the head 28 and the circumference of the shoe 26 is enlarged. According to the constitution, in comparison with the conventional pilot pipe device having the head eccentrically rotate, large sized gravel 88, etc., can be taken in the shoe 26. Gravel, etc., taken in are crushed by oscillating operation of the head 28. According to the constitution, in comparison with the conventional pilot pipe device having the head eccentrically rotate to crush gravel, etc., crushing force acted on gravel, etc. is increased even if driving force of the head 28 is decreased. Accordingly, gravel 88, etc., can be crushed with low driving force. |
