SHIELD MACHINE FOR EXISTING TUNNEL CONNECTING WORK EXECUTION

摘要

PROBLEM TO BE SOLVED: To provide a shield machine for existing tunnel connecting work execution allowing the continuous advance/retreat of a cutter ring in a wide range and simplifying a cutter head driving part. SOLUTION: An annular space chamber 5 is formed along the peripheral edge part of a front part of a shield body 1. A holding member 33 connected to the rotatable cutter head 2 side, and a cutter ring 31 protrusively provided with a plurality of cutting bits 32 at the front edge part, are provided in the annular space chamber 5. The cutter ring 31 is supported in a longitudinally slidable manner by the holding member 33, and working devices 41 for longitudinally sliding the cutter ring 31 are arranged in the annular space chamber 5. With the cutter ring 31 initially installed at the cutter head 2, the cutter ring 31 can be continuously advanced/retreated in a wide range by the actuation of the working devices 41. Connecting construction can thereby be efficiently performed, and the structure of a cutter head driving part can be simplified.