SHIELD MACHINE WITH ROCKING CUTTER

摘要

PROBLEM TO BE SOLVED: To solve a problem that there is no rocking cutter reconciling the collapse prevention of the natural ground at the upper section of a cutter head and the effective intake of the excavated sediment at the lower section. SOLUTION: A plurality of cutting tools are provided on the cutter face plates or spokes of the cutter head 4, and a drive device changing the rotating direction of the cutter head 4 to rock it is provided to form the rocking cutter 1. The natural ground is stably retained at the upper section of the cutter head 4, and the excavated sediment is effectively taken in at the lower section by setting the opening section area against the excavation cross sectional area of the rocking cutter 1 narrow at the upper section and wide at the lower section.