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摘要

PROBLEM TO BE SOLVED: To join a small-diametral shield at an eccentric place from the axial center of a large-diametral shield by eccentrically rotating a slave machine housed in a rotary drum to the axial center of a master machine in master-slave shield machines. ;SOLUTION: A slave machine 3 is housed in a rotary drum 2 arranged at an eccentric place to the axial center of a master machine 1, and a cutter head 4 consists of a central cutter 41, an intermediate cutter 42 and a peripheral cutter 43, and is constituted in a manner that the cutter head 4 can be engaged and disengaged mutually by engaging jacks 5 and engaging pins 6. The axial center of the slave machine 3 is conformed to the axial center of the master machine 1 at the time of the excavation of the master machine 1, and the whole cutter head 4 is turned integrally. The rotary drum 2 is rotated and the axial center of the slave machine 3 is moved upwards at the time of the excavation of the slave machine 3, engagement between the central cutter 41 and the intermediate cutter 42 is released, and the slave machine 3 is separated and started from the master machine 1. Accordingly, the slave machine 3 is started from an eccentric place to the axial center of the master machine 1, and a small diametral shield can be joined with a large diametral shield at the eccentric place.;COPYRIGHT: (C)1998,JPO