Abstract: A tunnel boring machine particularly adapted to operate at substantial depths below the earth's surface. The machine comprises a head section comprising a cutter head that is rotatably mounted to a support structure. There is a plurality of gripper shoes spaced circumferentially around the support structure, and these are operated to grip the tunnel wall and be selectively operated to advance the machine in the tunnel as the tunneling operation progresses. Also, there is a roof shield positioned immediately behind the cutter head. There is also a pair of support shoes supported from the support structure by links having curved bearing surfaces to maintain the machine at the proper distance above the tunnel invert. There is a beam structure having a forward end connected to the support structure by a universal connection, and the beam structure is supported by a rearwardly positioned gantry.

Abstract: A tunneling machine convertible between a "closed mode" and an "open mode" of operation, having a rotatable cutterhead with muck openings communicating with a pressurizable cutterhead chamber and a pressure maintenance system to stabilize the tunnel workface when operating in the "closed mode". In the "closed mode" low slurry flow is employed as a liquid pressure balance solely to support the unstable tunnel face. Low slurry flow is supplied through a pressure bulkhead sealing the cutterhead chamber and pressurized conveyor means through the bulkhead removes tunneled material from the cutterhead chamber. A pressure lock connected to the pressurized conveyor means transfers tunneled material to dewatering and reservoir/accumulator means operated at substantially atmospheric pressure.

Abstract: A hopper and hood combination for muck transfer in a tunneling machine, and a tunneling machine having the same, in which a muck collar is mounted to a cutterhead support and projects into a rotatable cutterhead. A muck chute on the muck collar feeds earth to an earth conveyer when the muck collar and muck chute are in a hopper orientation. The muck chute and muck collar are rotatable relative to the earth conveyor to a hood orientation in which the muck chute restricts earth flow to the earth conveyor. Rotation of the hopper/hood from one orientation to the other is by brief interconnection thereof to the cutterhead without any necessity for any disassembly or reconstruction of the tunneling machine.

Abstract: A shaft boring machine including a rotatable cutterwheel assembly with a horizontal axis mounted on a carriage having vertical travel. The carriage is mounted on a slewing base frame and rotates about the vertical axis of the machine. An excavating unit for muck removal is mounted opposite the cutterwheel on the slewing base frame and loads directly from the shaft bottom into a muck hopper. When the hopper is full, it is discharged into a hoist bucket which is hoisted to the surface. The machine is positioned in the shaft by upper and lower gripper systems. Walking cylinders between the two gripper rings advance the machine up or down the shaft.

Abstract: Front and rear shields are telescopically joined together. The front shield carries a power driven rotary cutterhead means. Thrust rams are provided between the two shields for pushing the forward shield forwardly relative to the rear shield while the cutterhead means is being operated to mine the tunnel face, and also to pull the rear shield forwardly relative to the front shield. The rear shield includes a gripper assembly for reacting thrust and torque and a plurality of auxiliary thrust rams which extend rearwardly from the rear shield to react against forward end portions of a tunnel lining which is erected under cover of a tail section of the rear shield. A pair of side placed torque cylinders are interconnected between frame portions of the two shields and serve to transmit counter-rotational torque from the cutterhead support of the front shield back to the rear shield.