| 摘要 |
PROBLEM TO BE SOLVED: To provide an excavator capable of favorably excavating natural ground including a bed rock stratum and a cohesive soil stratum and discharging excavated soil in a favorable condition without retension of soil in an excavated soil chamber. SOLUTION: An excavated soil chamber 7 is constituted of a peripheral wall 1a composed of a cutter head 4, a partition wall 5, and a part of a shield machine body at the front end of the shield machine body 1. A cone rotor 9 and an agitator blade driven by electrical motors are arranged at the lower part of the excavated soil chamber 7. A funnel-shaped crushing wall is formed at the periphery of the cone rotor 9 to form an agitation chamber. A discharge opening is formed in the vicinity of the basal end of the cone rotor 9 and connected to a mud discharge pipe 12. A plurality of protrusions 21 are formed on the peripheral wall 1a of the excavated soil chamber 7 and a crushing blade 22 positioned opposite to the protruded pieces 4c and spaced apart by a specified distance from the protruded pieces 4c is formed on the arm 4c of the cutter head 4. The crushing blade 22 is rotted in accordance with the rotation of the cutter head 4. When gravels are caught by the protruded piece 4c, shocks are given to the gravels to crush them. |
