TAIL SEAL REPLACEMENT MECHANISM FOR SHIELD MACHINE

摘要

PROBLEM TO BE SOLVED: To provide a shield machine with a tail seal replacement mechanism that can replace all of tail seals including those positioned at the rearmost row while reducing cost and term of works for replacement. ;SOLUTION: A mechanism that replaces tail seals 3a and 3b attached to the inner circumferential face of a tail plate 1 of a shield machine is equipped with an extension plate 4 connected to the rear end of the tail plate 1 and extending toward positions beyond the rear side of the tail seals 3a and 3b, a special segment 7 that is connected to an existing segment 2 and conveyed toward the rear side as excavation progresses and positioned, being opposite to the extension plate 4, and a seal member 12 that is provided at the outside in the diametral direction of the special segment 7 so that it can project and retreat freely and comes into contact with the extension plate 4 when being projected.;COPYRIGHT: (C)2000,JPO