SHIELD DRIVE MACHINE

摘要

PROBLEM TO BE SOLVED: To provide a shield drive machine capable of creating an excellent penetration performance to base rock and further of enhancing cutting performance for base rock without increasing the rotation load for cutting base rock. SOLUTION: In this shield drive machine. lead tools 12, 13 are respectively inserted to a supporting arm 10 in such a manner that the height X1 from the front end surface of a main excavation tool 11 at the tip portion of the lead tool 12 of a wedge-shaped cutting tool becomes high by a predetermined length from a height X2 from the front end surface of the main excavation tool 11 of the tip portion of the lead tool 13 of a flat type cutting tool; the locus of cutting is formed when the lead tool 12 of the wedge-shaped cutting tool makes a slide contact with a base lock for the first time ahead of the lead tool 13 of the flat type cutting tool; and thereafter, the lead tool 13 of the succeeding flat type scratches the locus of cutting formed on the base rock surface and makes slide contact with the base rock surface and forms a recessed gutter.