Tunnel excavating machine and excavating method

A tunnel excavation method for excavating and forming a tunnel with the tunnel excavating machine having a main portion provided with a cutter head mounted rotatably at a front portion thereof, an auxiliary portion provided inside the main portion movably in back and forth directions and provided with an erector integrally attached to the auxiliary portion for assembling the covering members, a plurality of main propulsion jacks disposed between the main portion and the auxiliary portion, and a plurality of auxiliary propulsion jacks mounted on the auxiliary portion and capable of being retracted with respect to the covering member, comprising:

• propelling the main portion by extending the main propulsion jack from an initial position wherein the main propulsion jacks and the auxiliary propulsion jacks are both retracted;
• propelling the auxiliary portion by extending the auxiliary propulsion jacks while retracting the main propulsion jacks;
• propelling the main portion by extending the main propulsion jacks while partially retracting each of the auxiliary propulsion jacks in succession;
• and
• sequentially assembling the covering members by the erector.

A tunnel excavating machine, comprising:

• a main portion provided with a cutter head mounted rotatably at a front portion thereof and fit to and external periphery of a covering member through a sealing member;
• an auxiliary portion provided inside the main portion, the auxiliary portion being movable in back and forth directions;
• an erector integrally attached to the auxiliary portion for assembling covering members;
• a plurality of main propulsion jacks disposed between the main portion and the auxiliary portion;
• and
• a plurality of auxiliary propulsion jacks mounted on the auxiliary portion, the propulsion jacks being capable of being extended as a group and individually retracted successively with respect to the covering member for sequentially assembling a plurality of covering members with the erector.

A method of manufacturing a tunnel excavating machine, comprising the steps of:

• providing a main portion having a cutter head mounted rotatably at a front portion thereof and fit to and external periphery of a covering member through a sealing member;
• providing, inside the main portion, an auxiliary portion movable in back and forth directions;
• integrally attaching an erector to the auxiliary portion for assembling covering members;
• providing a plurality of main propulsion jacks between the main portion and the auxiliary portion;
• and
• mounting a plurality of auxiliary propulsion jacks on the auxiliary portion, the propulsion jacks being capable of being extended as a group and individually retracted successively for sequentially assembling a plurality of covering members with the erector.

A tunnel excavating machine, comprising:

• a main portion provided with a cutter head mounted rotatably at a front portion thereof and fit to and external periphery of a covering member through a sealing member;
• an auxiliary portion provided inside the main portion, the auxiliary portion being movable in back and forth directions;
• an erector and an adjuster integrally attached to the auxiliary portion for assembling covering members and maintaining circularity thereof following assembly;
• a plurality of main propulsion jacks disposed between the main portion and the auxiliary portion;
• and
• a plurality of auxiliary propulsion jacks mounted on the auxiliary portion, the propulsion jacks being capable of being extended as a group and separately retracted successively with respect to the covering member for individually assembling a plurality of covering members with the erector.

A tunnel excavation method for excavating and forming a tunnel with the tunnel excavating machine having a main portion provided with a cutter head mounted rotatably at a front portion thereof, an auxiliary portion provided inside the main portion movably in back and forth directions and provided with an erector integrally attached to the auxiliary portion for assembling the covering members, a plurality of main propulsion jacks disposed between the main portion and the auxiliary portion, and a plurality of auxiliary propulsion jacks mounted on the auxiliary portion and capable of being retracted with respect to the covering member, comprising:

• propelling the main portion by extending the main propulsion jack from an initial position wherein the main propulsion jacks and the auxiliary propulsion jacks are both retracted;
• propelling the auxiliary portion by extending the auxiliary propulsion jacks while retracting the main propulsion jacks;
• propelling the main portion by extending the main propulsion jacks while partially retracting each of the auxiliary propulsion jacks in succession;
• and
• sequentially assembling the covering members by the erector while simultaneously propelling the main portion.