PURPOSE: To downsize a mechanism part, enhance excavation advancing accuracy and operability.
CONSTITUTION: Plural first propulsion cylinders 104 to receive cutter torque reaction by compression and plural second propulsion cylinders 105 to receive the cutter torque reaction by tension, are adjacently arranged in the circumferential direction between a rear base frame 101 and a front base frame 102, and head side end parts of the respective propulsion cylinders 104 and 105 are installed on the rear base frame 101 through a swivel bearing 103, and rod side end parts of the respective propulsion cylinders 104 and 105 are installed on the front base frame 102 through the swivel bearing 103. Since an inclination in the circumferential direction of the first propulsion cylinders 104 is made large and an inclination in the circumferential direction of the second propulsion cylinders 105 is made small so as to be adjusted to rated thrust force and cutter torque reaction, a mechanism part is downsized. The respective propulsion cylinders 104 and 105 are provided with a stroke position detector and a stroke position control device for excavation advancing accuracy and operability.
TANAKA AKIO
ISHISE FUMIHIKO
MATSUURA TAKESHI
