| 摘要 |
PURPOSE: To contrive effective propulsion by arranging a disc cutter provided with a self-sharpening function cutter and a cutter bit so as to help each other for hard crushing, providing a soil-intake opening taking in only soil at the front face, and equipping a scraper at the front end of a driving shaft. CONSTITUTION: A flat face plate 7 on which disc cutters 5, 6 and cutter bits 81 -86 , 91 , 92 , 101 , 102 are equipped in a cutter head dome 1. Crushed sand and soil are transferred from soil-intake openings 11-13 to a scraper 14 by these bits and discharged rearward by a screw 4 having blades attached to the drive shaft 3 without choking soil in the frame. The outermost peripheral cutter edge of the disc cutters 5, 6 has a shape for self-sharpening function, and a gravel caught in the soil-intake opening is crushed by the rotation of disc cutters 5, 6 to be taken in the cutter head 1. In this way, the cutter head can be used without choking even in case of clayey soil. |
