| 摘要 |
PROBLEM TO BE SOLVED: To improve workability, and to reduce cost by rotatably installing a cylindrical sealing body, on which an excavation cutter is mounted, into a cylindrical main body through a packing. SOLUTION: A cylindrical sealing body 3, in which the driving section 7 of an excavation cutter 5 is housed longitudinally movably, is set up rotatably at the front end section of a cylindrical main body 1 through an axis X2. An expansible and contractible cutoff packing 9 is fitted onto the inner peripheral wall of the main body 1, and abutted against a projecting section 8 formed to the outer circumference of the sealing body 3 in a ring shape. When a bit for the cutter 5 is exchanged, the cutter 5 is shrunk, the driving section 7 is moved backwards and the cutter 5 is housed in the sealing body 3, and covers are installed to the opening sections of partition walls 14, 16. The packing 9 is contracted and separated from the projecting section 8, the sealing body 3 is rotated at 180 deg., the packing 9 is expanded and brought into contact with the projecting section 8 and water is stopped, and the cover for the partition wall 16 is opened and works are conducted from the inside of the machine of the main body 1. Accordingly, since the sealing body is not formed in a spherical surface, the shield machine can be manufactured easily at low cost. |
