JP2000213284A - Tunnel excavator and roller cutter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a tunnel excavator capable of performing the excavation with excellent accuracy while efficiently crushing large stones and rocks. SOLUTION: In this tunnel excavator provided with a cutter frame 4 of the specified shape connected to drive shafts of a plurality of rotating motors through a crank 5, performing the parallel link motion copying a tunnel excavation section by the synchronous operation of the drive shafts, roller cutters 10 are arranged along the longitudinal direction of the frames at the front side on a cutting face side of the cutter frames 4 so that a rotary shaft 21 of a disk cutter 20 is rotated in the normal direction orthogonal to the advancing direction accompanied by the parallel link motion of the cutter frame 4.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tunnel excavator and a roller cutter, and more particularly to a tunnel excavator in which a roller cutter is mounted on a multi-axis eccentric cutter mechanism for excavating a boulder or a bedrock, and an efficient boulder or the like. It relates to a roller cutter that breaks well.

[0002]

2. Description of the Related Art In recent years, in a shield tunnel, a rectangular, elliptical, or horseshoe-shaped tunnel section has been required in addition to a conventional circular section. As a tunnel excavator that can meet this demand, a shield excavator equipped with a multi-axis eccentric cutter mechanism has been developed. FIG. 8 is a schematic front view of an example of the shield excavator 50 provided with the already developed multi-axis eccentric cutter mechanism 51 as viewed from the cutter head side. As shown in the figure, this shield excavator 50 is an excavator capable of excavating a tunnel 60 having a rectangular cross section with rounded corners. In a cutter chamber 53 surrounded by a rectangular skin plate 52, a cutter frame 54 having a square frame shape is attached to drive shafts of four cutter motors (not shown) disposed at four corners thereof. It is supported via a crank arm 55. The four cutter motors are controlled by an operation unit (not shown) so as to perform synchronous operation in which the direction and the number of revolutions are matched. That is, the cutter frame 54 assembled to form a parallel link mechanism with respect to the drive shaft via the crank arm 55 has a predetermined planar shape with the rotation of the crank arm 55 by the synchronous rotation of the four cutter motors. Perform a parallel link motion that draws a trajectory. The trajectory of the cutter frame 54 matches the cross section of the tunnel surrounded by the skin plate 52 as shown in FIG. In the tunnel excavator 50 having the multi-axis eccentric cutter mechanism 51, it is possible to cope with various tunnel cross sections by changing the arrangement of the rotating shaft, the length of the crank arm, and the shape of the cutter frame supported by the crank arm. it can.

At this time, cutter bits 57 are mounted at predetermined intervals on the outer periphery of the cutter frame 54 and on the cross-shaped stiffening frame 56, and the cutting ground is cut along the locus of the cutter frame 54. be able to. Further, since each cutter bit 57 cuts the ground along the same trajectory, there is an advantage that the wear of each cutter bit is also uniform.

[0004]

The cutter bit 54 shown in FIG. 9 is mounted on the cutter frame 54 of the tunnel excavator shown in FIG. In this tunnel excavator, since the cutter bit cuts the ground along a fixed trajectory, the tip of the cutter bit contacts the ground at various angles to cut the ground. For this reason, a carbide tip 58 is embedded at the tip so as to form a cross. Since the cutter bit 54 called a cross roof bit cuts the ground with the tip 58, the excavated soil is limited to silt, clay, sand and the like. For this reason, excavation in boulders and bedrock is difficult.

On the other hand, there is a roller cutter employed as a bit capable of excavating boulders and rocks in a tunnel boring machine (TBM). This roller cutter is TBM
Attached to the cutter frame at the tip of the, the disc cutter is pressed against the ground (gravels, rocks), etc., where the disc cutter is to be cut, and rocks and boulders are crushed by the crushing force of the disc cutter that rotates around the rotation axis as the cutter frame rotates It is supposed to.
When this roller cutter is applied to a tunnel excavator as shown in FIG. 8 instead of the cross-roof bit of the multi-axis eccentric cutter mechanism described above, when the cutter frame draws a locus defined as a parallel link, There is a problem in that the rotation direction and the moving direction of the cutter frame that change variously form an angle, and the disc cutter of the roller cutter cannot rotate smoothly around the rotation axis.
For this reason, gravels and rocks cannot be efficiently cut, and the damage of the disk cutter itself progresses rapidly.

[0006] Therefore, an object of the present invention is to solve the above-mentioned problems of the prior art, and to apply the present invention to a roller cutter mounted on a multi-axis eccentric cutter mechanism and to excavation of boulders, hard rock and the like. To provide a tunnel excavator.

[0007]

In order to achieve the above object, the present invention relates to a parallel link which is connected to the drive shafts of a plurality of rotary motors via a crank, and which is synchronized with the cross section of the tunnel excavation by the synchronous operation of the drive shafts. In a tunnel excavator provided with a cutter frame having a predetermined shape that moves, in a longitudinal direction of the frame on the front face side of the cutter frame, the cutter frame faces a normal direction perpendicular to a traveling direction accompanying the parallel link movement of the cutter frame. Thus, the roller cutter in which the rotating shaft of the disk cutter rotates is provided.

[0008] As a roller cutter, a mounting seat fixed to a mounting hole formed in a part of a cutter frame mounted on a tunnel excavator, and the mounting seat is rotatable about a predetermined rotating shaft via a bearing. A base is accommodated, and one of the rotating shaft supports is extended from the base toward the face, and the disk cutter is attached to the rotating shaft support so as to have a predetermined inclination angle with respect to the face on the face side of the cutter frame. Characterized in that the rotary shaft is supported.

The roller cutter may be configured such that the cutter frame is connected to a drive shaft of a plurality of rotary motors via a crank, and performs a parallel link motion following a tunnel excavation cross section by synchronous operation of the drive shaft. The rotation axis of the disk cutter rotates in a normal direction perpendicular to a traveling direction accompanying the parallel link movement of the cutter frame along a longitudinal direction of the frame on the front face on the face of the cutter frame.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a tunnel excavator and a roller cutter attached to the tunnel excavator according to the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a schematic front view of a tunnel excavator 1 provided with a multi-axis eccentric cutter mechanism as viewed from a cutter head side. In the present embodiment, a circular cross section having a tunnel diameter D _T is excavated using parallel link motion of a circular cutter frame 4 having a diameter D _C provided in a cutter chamber 3 surrounded by a cylindrical skin plate 2. It has become. The circular cutter frame 4 includes a ring-shaped outer peripheral frame 4A as shown by a solid line, two vertical stiffening frames 4B extending in a vertical direction for securing roundness and a flat surface of the outer peripheral frame 4A, and a vertical stiffening frame 4B. It is composed of a rigid frame 4B and a horizontal stiffening frame 4C orthogonal to the rigid frame 4B. The cutter frame 4 is supported via three crank arms 5 on the drive shafts of three cutter motors (not shown) installed on the bulkhead side as components similar to the conventional multi-axis eccentric cutter mechanism. ing.
The three cutter motors are controlled by an operation unit (not shown) so that a synchronous operation in which the directions and the number of rotations are matched can be performed. That is, the cutter frame 4 assembled so as to constitute a parallel link mechanism with respect to the drive shaft via the crank arm 5 has a synchronous state of the three cutter motors as shown partially in the phantom line. With the rotation of the crank arm 5 due to the rotation, a parallel link motion that draws a circular locus having a diameter _DT is performed. At the lower end of the bulkhead, a screw conveyor 7 for carrying excavated earth and sand to the rear of the tunnel excavator 1 is provided.

The outer peripheral frame 4A of the cutter frame 4
A plurality of roller cutters 10, 10... Are mounted at predetermined intervals along the longitudinal direction of the frame on the face side front surface of the stiffening frames 4B, 4C. The configuration of the roller cutter 10 will be described with reference to FIGS. FIG. 2 shows a front view of one roller cutter 10 attached to the cutter frame 4. The roller cutter 10 has a mounting seat 11 directly fixed to the cutter frame 4.
And a disk support rotary seat 12 whose part is housed in the mounting seat 11 via a bearing, and a disk cutter 20 mounted on a rotary shaft 21. The rotation shaft 21 is supported by the rotation shaft support arms 17a and 17b.

The above components will be described with reference to the drawings. In the present embodiment, the cutter frame 4 is
As shown in the figure, the section has a substantially rectangular steel pipe section, and a part of the front surface thereof is hollowed out to form a mounting hole 4a to accommodate the base 12a of the mounting seat 11 of the roller cutter 10. As shown, the mounting seat 11 has a flat circular dish shape, and has a dish-shaped recess 11a formed therein.
A flange 11b is formed around the shoulder of the dish-shaped recess 11a. The mounting seat 11 is fixed to a predetermined position of the cutter frame 4 by mounting bolts 15 via bolt holes (not shown) provided in the flange 11b. Further, roller bearings are mounted on the bottom surface and the inner side surface of the dish recess 11a of the mounting seat 11, as shown in FIG. That is, the thrust bearing 14 is provided on the bottom surface of the disk supporting rotary seat 1.
The second rotation center shaft 16 is disposed around the rotation center shaft 16. Further, a radial bearing 13 is provided on the inner side surface at a boundary position with the outer periphery of the disk supporting rotary seat 12 having a cylindrical shape. As the type and structure of the bearing, various known types can be adopted as long as the structure can rotate so that the thrust force applied from the disk cutter can be supported. Similarly, as long as the cross-sectional specifications of the cutter frame satisfy the mechanical specifications, various types such as a circular pipe and a solid member can be applied. It goes without saying that the front shape of the mounting seat is not limited to a circle.

As shown in the drawing, the outer shape of the base 12a of the disk support rotary seat 12 is set to match the inner peripheral dimension of the dish-shaped recess 11a of the mounting seat 11, and the two types of bearings 13, 14 and can be rotated in the direction of arrow A about the rotation center axis 16 with respect to the mounting seat 11. Further, rotating shaft supporting arms 17a and 17b are protruded from a base 12a of the disk supporting rotating seat 12.
The rotating shaft support arm 17a is formed such that the rotating shaft 21 of the disk cutter 20 forms an inclination angle θ with respect to the vertical axis. In other words, one of the shaft ends of the disk support rotary seat 12 is extended with respect to the face, and the rotary shaft 21 of the disk cutter 20 is tilted by a predetermined tilt angle θ with respect to the face on the face of the cutter frame 4. ing. The rotating shaft 21 of the disk cutter 20 is mounted on the rotating shaft support arm 17.
The shafts 17a and 17b are rotatably supported in the vicinity of the distal ends, and can rotate around the rotation center axis 18 in the direction of arrow B (see FIG. 3). When the parallel link moves along a predetermined trajectory, the disk cutter 20
The disk support rotary seat 12 can be rotated around the rotation center axis 16 so that the rotation resistance received from the ground is minimized. As the disk cutter 20, a special steel cutter subjected to a known induction hardening is used.

Here, the rotating shaft 21 of the disk cutter 20
A description will be given of the rotation operation of the disk cutter about the rotation center axis 16 when reducing the resistance from the ground that hinders the rotation around the disk. First, when the cutter frame 4 makes a predetermined parallel link motion, the outermost edge of the disk cutter 20 has a cutting edge P.
Is pressed against a hard ground in an inclined state. Therefore, smooth rotation of the disk cutter 20 around the rotation axis 21 is hindered. At the same time, the resistance from the ground causes the disk support rotary seat 12 to rotate in the rotation direction A with respect to the rotation center axis 16.
As shown in FIG. 3, the eccentric couple acts on the cutting edge P of the disk cutter 20. As a result, the disk cutter 20 moves in the normal direction perpendicular to the traveling direction accompanying the parallel link movement of the cutter frame 4 (tangential direction of the trajectory of the parallel link).
, That is, the position where the resistance from the ground is minimized, rotates around the rotation center axis 16.

Next, the rotation operation of the disk cutter 20 will be described in relation to the parallel link movement of the cutter frame (see FIGS. 4 and 5). FIG. 4 shows a part of the cutter frame 4 of the tunnel excavator shown in FIG.
V) is a schematic diagram partially showing an arc-shaped trajectory drawn by a parallel link motion. As shown in the drawing, the cutter frame 4 including the focused roller cutter 10 rotates 90 ° counterclockwise from a position along an arc-shaped locus having a radius of curvature R. At this time, the disc supporting rotary seat 12 rotates around the rotation center axis 16 of the mounting seat 11 in such a direction that the disc cutter 20 mounted on the roller cutter 10 also coincides with the tangential direction of the arc between the respective positions (1) to (4). ) To rotate counterclockwise. Therefore, the disk cutter 20 can always be positioned so that its cutting edge P is orthogonal to the ground, and the rotational resistance at the time of ground cutting can be minimized. In other words, when the target disk cutter 20 draws an arc-shaped trajectory as shown in FIG.
The rotation axis of the disk cutter 20 rotates so as to face a normal direction perpendicular to the traveling direction (in the case of an arc, the center point C of the arc).

FIG. 5 shows a part of the cutter frame 4 having a substantially rectangular shape shown in FIG. As shown in the figure, the cutter frame 4 extending in the horizontal direction descends in the vertical direction, and moves along the horizontal direction after cutting a corner having a predetermined radius of curvature. When the cutter frame 4 draws such a trajectory, the disk cutter 20 is held in a vertical plane perpendicular to the plane of the paper and an inclined plane θ at a position, and is inclined to a horizontal plane perpendicular to the plane of the paper to the right of the position. It is held in a plane containing a horizontal line inclined by the angle θ. At the position between them, it rotates counterclockwise so as to change the angle along the arc as in the case of FIG. 4, and the state where the rotating shaft 21 faces the center point C of the arc is maintained.

FIG. 6 shows a low-cost and robust type of roller cutter 10 in which the rotation axis of the disk cutter 20 does not have an inclination angle with respect to the disk support rotary seat 12. The roller cutter 10 shown in FIG. 1 can efficiently generate an eccentric couple of the disk support rotary seat 12 with respect to the mounting seat 11 by giving an offset having an inclination angle θ to the rotary shaft 21, The rotation of the rotating seat 12 was smoothly performed.
On the other hand, in the disk support rotary seat 12 shown in FIG. 6, the arm lengths of the shaft support portions 17a and 17b at both ends of the rotary shaft 21 are designed to be equal. Therefore, the manufacturing cost can be reduced. However, smooth rotation may not be expected when the cutter frame 4 (parallel link) draws a curved trajectory as compared to the case where there is an offset. Therefore, it is preferable that the disk support rotary seat 12 having such a shape is applied to a multi-axis eccentric cutter mechanism in which the parallel link includes many linear trajectories as shown in FIG.

FIG. 7 is a partial sectional view showing a modification in which the disk cutters 20 are arranged in multiple rows with respect to the rotation axis. As shown in the figure, it is preferable to reduce the disk diameter on the side where the offset amount of the shaft end is large, and to design so that the cutting edge P of each disk cutter 20 abuts on the face 30 substantially in the same plane. As described above, also in the case of a multi-row cutter, since the rotating shaft 21 of the disk cutter 20 is attached with a predetermined offset with respect to the front surface of the cutter frame 4, the disk supporting rotary seat 12 is shown in FIG. A rotation operation similar to that of the structure can be realized.

[0019]

As described above, by arranging the roller cutter on the cutter frame of the multi-axis eccentric cutter mechanism so that the disk cutter rotation axis has a predetermined offset, it can be specially applied to the ground or bedrock containing boulders. This has an effect that a tunnel having a cross section can be excavated.

[Brief description of the drawings]

FIG. 1 is a schematic front view showing an embodiment of a tunnel excavator according to the present invention.

FIG. 2 is a partial front view showing an embodiment of the roller cutter of the present invention.

FIG. 3 is a cross-sectional view showing the roller cutter shown in FIG. 2 along a line III-III.

FIG. 4 is a state explanatory view showing a rotating state of a disk supporting rotary seat of a roller cutter accompanying a parallel link movement of the cutter frame.

FIG. 5 is a state explanatory view showing a rotating state of a disk supporting rotary seat of a roller cutter accompanying a parallel link movement of a cutter frame of another shape.

FIG. 6 is a cross-sectional view showing another embodiment of the roller cutter of the present invention.

FIG. 7 is a cross-sectional view showing another embodiment of the roller cutter of the present invention.

FIG. 8 is a schematic front view showing a conventional example of a tunnel excavator having a multi-axis eccentric cutter mechanism.

FIG. 9 is a schematic perspective view showing an example of a cross roof bit attached to the cutter frame shown in FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tunnel excavator 4 Cutter frame 5 Crank 10 Roller cutter 11 Mounting seat 12 Disk support rotary seat 13,14 Bearing 16,18 Rotation center axis 20 Disk cutter 21 Rotation axis

Claims (3)

[Claims] 1. A tunnel excavator having a cutter frame of a predetermined shape connected to drive shafts of a plurality of rotary motors via a crank and performing parallel link movement following a tunnel excavation cross section by synchronous operation of the drive shafts. A roller cutter in which a rotation axis of a disk cutter rotates so as to face a normal direction orthogonal to a traveling direction accompanying a parallel link motion of the cutter frame along a frame longitudinal direction on a front face of the cutter frame on a face side of the cutter frame. Tunnel excavator characterized by being done. 2. A mounting seat fixed to a part of a cutter frame mounted on a tunnel excavator, and a base is accommodated in the mounting seat so as to be rotatable about a predetermined rotation axis via a bearing,
By extending one of the rotating shaft support portions from the base to the face side,
A roller cutter for a tunnel excavator, wherein a rotating shaft of the disk cutter is supported by the rotating shaft support portion so as to have a predetermined inclination angle with respect to a front surface on a face side of the cutter frame. 3. The cutter frame is connected to drive shafts of a plurality of rotary motors via a crank, and performs a parallel link motion following a tunnel excavation cross section by synchronous operation of the drive shafts. 3. The tunnel excavator according to claim 2, wherein the rotation axis of the disk cutter rotates in a normal direction perpendicular to a traveling direction accompanying the parallel link movement of the cutter frame along a longitudinal direction of the frame on the front face on the face side. For roller cutter.