JPH0781506B2 - Free-section shield method and shield machine - Google Patents

Description

TECHNICAL FIELD The present invention relates to a free-section shield method and a shield machine capable of continuously excavating not only a circular shape but also a tunnel having an irregular cross-sectional shape other than a circular shape. is there.

[Conventional technology]

As a conventional shield construction method, by rotating a cutter arranged on the front surface of the shield machine around the central axis of the shield machine, the front surface of the shield machine in the propelling direction is excavated, and the shield machine is propelled as much as the excavated portion. It is common to dig by adding segment rings.

However, since such a construction method excavates only by rotating the front cutter, the excavated cross section is limited to a circular shape, and it is difficult to excavate a tunnel having an irregular cross section other than the circular shape. On the other hand, most of the actual cross-sectional shapes of tunnels such as sewers, power lines, and subways are not circular, so
Conventionally, excavation of a large circular cross-section that includes this irregular cross-sectional shape has been unavoidable, which has been accompanied by inconveniences such as high cost.

Therefore, the present applicant has previously proposed a shield construction method and a shield machine capable of continuously excavating a cross section of a desired shape other than a circle (see Japanese Patent Application No. 63-81829). This is because, in a shield machine as shown in FIGS. 16 and 17, by rotating the center cutter 101 around a horizontal axis (X axis), the central circular portion on the front surface in the propulsion direction is excavated, and The side cutter 102 arranged on the outer peripheral side of the cutter 101 is revolved around the center cutter 101 while rotating around the horizontal rotary shaft 104 to excavate the outer peripheral portion of the circular portion, wherein the side The cutter 102 is revolved along a guide frame 103 having a similar shape to a desired excavation cross-sectional shape.

According to such a shield construction method and a shield machine, by appropriately setting the shape of the guide frame, it is possible to dig a tunnel having a modified cross-sectional shape similar to the guide frame.

[Problems to be Solved by the Invention]

Since the shield method and the shield machine as described above revolve the side cutter along the guide frame having a special shape, the following problems remain.

(1) Rotating shaft 104 of side cutter 102 and guide frame 10
Since the engagement maintaining means such as the air cylinder 105 is required to maintain the engagement with the peripheral surface of 3, the structure becomes relatively complicated.

(2) Since the end of the rotary shaft 104 of the side cutter 102 is pressed against the guide frame 103, a large bending moment acts on the rotary shaft 104, and not only the rotary shaft 104 but also a bearing or the like that supports the rotary shaft 104. Also, great strength is required.

(3) Rotating shaft 104 of side cutter 102 and guide frame 10
The revolution trajectory of the side cutter 102 is maintained by the engagement of 3, and the revolution trajectory is uniquely determined by the shape of the guide frame 103.Therefore, the revolution trajectory of the side cutter 102, that is, the excavation cross section, is easily obtained during excavation. The shape cannot be changed.

In view of such circumstances, the present invention can obtain an irregularly shaped excavation cross-sectional shape with a simple structure, has a small load on the rotating shaft of the cutter, and easily changes the cross-sectional shape. It is an object of the present invention to provide a free-section shield construction method and a shield machine that can be used.

[Means for Solving the Problems]

The shield construction method of the present invention is a shield construction method of excavating by propelling a cutter in a direction substantially parallel to the axis while rotating the cutter about a predetermined axis, while rotating the center cutter around the first axis and The planetary cutter is revolved around a second axis that revolves around the first axis, and the planetary cutter revolves around the first axis while drawing a locus according to a desired cross-sectional shape. Controlling the revolution angle of the planetary cutter around the second axis with respect to the revolution angle of the second axis around, and rotating the planetary cutter around a third axis parallel to the first axis and the second axis. It is what makes me.

Also, as a shield machine that realizes this shield construction method,
A propulsion unit that propels the entire apparatus, a center cutter that rotates about a first axis that is substantially parallel to the propulsion direction, a large rotating body that rotates about the first axis, and a rotational drive of the large rotating body and the center cutter. First driving means, a small rotating body attached to the large rotating body so as to be rotatable about a second axis parallel to the first axis, and a second driving means for rotationally driving the small rotating body. A planetary cutter attached to the small rotating body so as to be rotatable about a third axis parallel to the first axis and the second axis; and third drive means for rotationally driving the planetary cutter. Some planetary cutters are provided with a drive control system that controls the drive of the large rotating body and the small rotating body so as to revolve around the first axis while drawing a locus according to a preset cross-sectional shape.

[Action]

According to the shield construction method and the shield machine having the above-described configuration, the central circular portion on the front surface of the excavation is excavated by the rotation of the center cutter, and the outer peripheral portion of the second circular portion revolves around the first axis while the planetary cutter revolves around the first axis. It is excavated by revolving around the axis. Moreover, since this revolution locus corresponds to a preset desired excavation sectional shape, the peripheral edge of the outer peripheral portion excavated by the planetary cutter has a desired excavated sectional shape.

〔Example〕

A first embodiment of the present invention will be described with reference to FIGS.

The shield machine shown in FIGS. 1 to 8 is provided with a skin plate 1 in the shape of a rectangular tube, and a cutting wheel (major body of revolution) 2 is built in the tip portion of the skin plate 1. The cutting wheel 2 is connected to a front end portion (left end portion in FIG. 2) of a center shaft 3 extending in the propulsion direction of the shield machine, and both are integrally rotated.

The outer peripheral portion of the cutting wheel 2 and the end portion of the center shaft 3 are supported by the skin plate 1 via bearings 4 and 5, respectively. The bearing 5 supports a radial load and a thrust load, and the thrust load acting on the cutting wheel 2 during excavation is a bearing support frame extending sequentially from the center shaft 3, the bearing 5, and the skin plate 1. It is transmitted to the skin plate 1 via 6. That is, the cutting wheel 2
Are supported by bearings 4 and 5 both in the radial direction and the thrust direction, and are freely rotatable about the center shaft 3.

Rear end of the center shaft 3 (right end in FIG. 2)
A large gear 7 is fixed to. On the other hand, a gear casing 8 is provided on the bearing support frame 6, and a wheel drive geared motor (first drive means) 10 is attached to a lid 9 of the gear support casing 8. The gear support casing 6 is attached to an output shaft of the motor 10. The pinion 11 is meshed with the large gear 7. Therefore, the cutting wheel 2 is rotationally driven by the operation of the wheel driving geared motor 10.

The cutting wheel 2 has a chamber 12 which is an internal space.
A pair of bosses 13 each having a cylindrical hole are provided in the chamber 12 at symmetrical positions sandwiching the center shaft 3 from both sides. A rotary wheel (small rotating body) 15 having an eccentric hole 14 is rotatably inserted into these bosses 13 via a bearing 16, and a planetary cutter drive shaft 17 is freely rotatable in the eccentric hole 14 via a bearing 18. Has been inserted into. This planetary cutter drive shaft 17
A gear 19 is formed at the rear end, and a planetary cutter 22 having a cutter bit 31 on the entire outer peripheral portion of the front surface is fixed to the front end.

A rotary wheel lid 20 is attached to the rear end of the rotary wheel 15, and a planetary cutter driving geared motor (third driving means) 21 of the rotary wheel lid 20 is attached. Pinion 11 mounted on 21 output shafts
1 is meshed with the gear 19. Therefore, the operation of the planetary cutter driving geared motor 21 causes the planetary cutter to operate.
22 is driven to rotate. Further, on the outer peripheral surface of the rear end portion of the rotary wheel 15, a gear 23 having teeth around the entire circumference thereof is formed.

A rotary wheel drive device 26 is attached to the center shaft 3 via a bracket 27. The rotary wheel drive device 26 includes a rotary wheel drive geared motor (second drive means) 24, a pinion 112 attached to the output shaft of the geared motor 24, an idle gear 25 meshed with the pinion 112, and the like. The idle gear 25 is the rotating wheel
It is meshed with a gear 23 at the rear end of 15. Therefore, the operation of the geared motor 24 for driving the rotary wheel causes the pinion 11 to move.
2. The rotating wheel 15 is rotationally driven via the idle gear 25.

In front of the cutting wheel 2 is a planetary cutter 22.
A face plate 30 in which only the installation portion is cut out is arranged, and the front surface of the planetary cutter 22 and the front surface of the cutting wheel 2 (that is, the front surface of the face plate 30) are arranged substantially at the same level. By disposing this face plate 30, it is possible to prevent only the planetary cutter 22 from projecting largely forward, the face of the face (cutting surface of the earth and sand by the shield machine) is stabilized, and smooth excavation work of the shield machine is secured. It has become so.

As with the planetary cutter 22, a large number of cutter bits 311 and 312 for cutting earth and sand are arranged on a part of the face plate 30. Therefore, this face plate 30
Further, the cutter bits 311 and 312 arranged on the surface constitute a center cutter that rotates around the center shaft 3.

Further, the face plate 30 and the cutting wheel 2 are provided with a plurality of windows 32, and these windows 32 are communicated with the chamber 12 of the cutting wheel 2, and the earth and sand cut by the cutter bit 31 are passed through the window 32. After being guided to the chamber 12, it is conveyed rearward by a screw conveyor (not shown) provided inside the center shaft 3, and further discharged to the outside by a belt conveyor (not shown) not shown. It has become.

In addition to the above, the outer periphery of the center shaft 3 is provided with a slip ring 33 for transmitting power (electricity or hydraulic pressure) to the rotary wheel driving geared motor 24 and the planetary cutter driving geared motor 21, and the skin plate 1 A shield jack (propulsion means) 34 for propelling the shield machine and an erector 35 for laying the segment 50 on the inner wall of the excavated tunnel are arranged in the rear part.

Further, a drive control system as shown in FIG. 9 (block diagram) is provided inside the shield machine.

Cutting wheel rotational position detector 80 shown
Is for determining a reference rotational position of the cutting wheel 2 and detecting a rotational displacement amount (for example, an angle) of the cutting wheel 2 with respect to the reference rotational position. As the reference rotational position, for example, a position where one of the centers P ₂ (see FIG. 5) of the two rotary wheels 15 comes directly above the center P ₁ of the cutting wheel 2 or the like is set.

The rotary wheel rotational position detector 84 determines a reference rotational position of the rotary wheel 15 and detects a rotational displacement amount of the rotary wheel 15 with respect to the reference rotational position. As the reference rotation position, for example, a position where the center P ₃ of the planetary cutter 22 comes closest to the center P ₁ of the cutting wheel 2 or the like is set.

The arithmetic unit 81 is a rotary wheel required for the rotational displacement amount of the cutting wheel 2 when obtaining a predetermined excavation cross section.
A program for calculating the rotational displacement amount of 15 is installed, and the rotational displacement amount of the rotary wheel 15 required for the rotational displacement amount of the cutting wheel 2 input from the cutting wheel rotational position detector 80 is instantaneously measured. Calculate to. The details of the calculation will be described later.

The comparator 82 includes an arithmetic unit 81 and a rotary wheel rotational position detector 84.
Comparing the rotational displacement amounts respectively input from, give a forward or reverse command to the rotating wheel drive geared motor controller so that the rotating wheel 15 rotates in a direction in which both are equal,
It gives a stop command when the difference between the two disappears.

When a hydraulic motor is applied as the rotary wheel driving geared motor 24, a servo valve may be used for the rotary wheel driving geared motor controller 83.

Next, the operation of this shield machine will be described.

First, the planetary cutter driving geared motor 21 is operated to rotationally drive each of the two planetary cutters 22, and then the wheel driving geared motor 10 is driven to rotationally drive the cutting wheel 2. When the shield jack 34 is gradually extended, the tip of the shield jack 34 comes into contact with the laid segment 50, and a propulsive reaction force is taken from the segment 50 to move the entire shield machine forward. In this state, since the cutting wheel 2 is rotating, the cutting bit 311 provided on the face plate 301,
While the 312 moves circularly while cutting the earth and sand, and the planetary cutter 22 revolves while revolving around its own axis, the cutter bit 31 provided in the planetary cutter 22 also cuts the earth and sand.

At this time, if the rotary wheel drive gear motor 24 is stopped, only the earth and sand in front of the cutting wheel 2 are cut, and the earth and sand at the corners of the skin plate 1 are not cut at all. By driving the drive geared motor 24, the rotating wheel 15 is rotationally driven through the pinion 112 attached to the output shaft and the idle gear 25, so that the cutter bit provided on the outer peripheral portion of the planetary cutter 22. 31 reaches the corner portion of the skin plate 1, and it becomes possible to excavate a portion other than the circular shape.

The specific movement will be described. As shown in FIG. 5, the planetary cutter drive shaft 17 passing through the center of the planetary cutter 22.
The center (third axis) P ₃ of the shaft is eccentric from the center (second axis) P ₂ of the rotating shaft 15 by a distance l ₁ . Therefore, when the rotary wheel 15 rotates, the center P ₃ of the planetary cutter drive shaft 17 comes into contact with and separates from the center (first axis) P ₁ of the cutting wheel 2, and as a result, the planetary cutter 22 of the cutting wheel 2 moves. It will move away from the center P ₁ .

Therefore, if the gear wheel motor 24 for driving the rotating wheel is operated and the rotating wheel 15 is appropriately driven, the distance from the center P ₁ of the cutting wheel 2 to the center P ₃ of the planetary cutter 22 is changed within the range shown by the following equation. Can be made.

_{l 2 + l 1 ≧ l ≧} l 2 -l 1 wherein, l _2: distance from the center P ₁ of the cutting wheel 2 to the center P ₂ of the rotating wheel 15 l: planetary cutter from the center P ₁ of the cutting wheel 2
Distance to Center P _{3 of} 22 When cutting a rectangular cross section as in this embodiment, the rotary wheel reaches the position where the above distance l becomes the maximum when the planetary cutter 22 passes through the corner of the rectangular cross section. 15 should be rotated.

For example, as shown in FIG. 7, in a state in which the pair of rotating wheels 15 are located on the diagonal line, by rotating each rotating wheel 15 from the position shown in FIG. The excavation area can be expanded to the corners of the polygon. On the contrary, as shown in FIG. 8, when the cutting wheel 2 is rotated 90 ° from the position shown in FIG.
The rotating wheel 15 may be rotated so that the distance between the planetary cutters 22 is reduced, that is, the distance 1 is reduced. That is, by changing the rotational position of the rotary wheel 15 according to the rotational angle of the cutting wheel 2, it is possible to automatically obtain a predetermined excavation cross section.

Therefore, in the drive control system shown in FIG.
First, the arithmetic unit 81 calculates the rotational displacement amount of the rotary wheel 15 required to obtain a desired sectional shape for each rotational position of the cutting wheel 2, and the calculated rotational displacement amount is actually detected. The rotating wheel 15
By controlling the rotation drive of the center of the planetary cutter 22, the planetary cutter 22 draws a locus corresponding to the desired excavation cross-sectional shape.
Can be revolved around P ₁ . It should be noted that the rotation range of the rotary wheel 15 may be forward and reverse rotation within a rotation range of 180 °, as is clear from FIGS. 5 and 7, 8.

Therefore, according to this shield machine and the shield construction method based on the shield machine, various excavation cross-sectional shapes can be automatically and easily obtained by appropriately converting the program incorporated in the arithmetic unit 81. A few examples will be described below.

The small circle 90 shown by the alternate long and short dash line in FIG. 10 is obtained when the cutting wheel 2 is rotated with the center P ₂ of the planetary cutter 22 being closest to the center P ₁ of the cutting wheel 2 and the center shaft 3. It is the excavated cross-sectional shape. Further, the great circle 91 shown in the figure is an excavated cross-sectional shape obtained when the cutting wheel 2 is rotated with the center P ₂ of the planetary cutter 22 being farthest from the center P ₁ of the cutting wheel 2. is there.

Therefore, the excavated cross section obtained by controlling the revolution trajectory of the planetary cutter 22 is limited to the range surrounded by the small circle 90 and the large circle 91. For example, the polygon shown by the solid line in Figure 10
The outer peripheral shape of the skin plate 1 in the shape of a rectangular tube 92 is shown, but as is clear from the figure, the square 92 is contained within the above range.

FIG. 11 is an example in which the horseshoe shape 93 is accommodated within the above range.
In this case, the skin plate 1 having the outer peripheral shape of the horseshoe shape 93 may be used, and a program for matching the revolution trajectory of the planetary cutter 22 with the horseshoe shape may be incorporated in the arithmetic unit 81.

Further, FIG. 12 shows an example in which the oval outer peripheral shape 94 is accommodated within the above range.

As described above, according to the shield machine and the shield construction method based on the shield machine, the program of the arithmetic unit 81 is changed,
Moreover, only by changing the shape of the skin plate 1 to the shape corresponding to the program of the arithmetic unit 81, various excavated cross sections can be easily obtained by a single shield machine.

Furthermore, even more excellent effects can be obtained by performing so-called overcut in this shield machine. This overcut will be described with reference to FIG.

In the figure, hatched portions A to D shown on the outer side of the outer peripheral shape 92 of the skin plate 1 are overcut zones. In normal excavation, the outer peripheral portion of the planetary cutter 22 has an outer peripheral shape according to a program installed in the arithmetic unit 81.
Controlled to move along 92, computing device 81
In addition to the block for realizing this, the outer peripheral shape 92 in which the hatching portion A is added to the outer peripheral shape 92 of the skin plate 1
A program for moving the planetary cutter 22 along a, an outer peripheral shape 92b with a hatched portion shown by B, an outer peripheral shape 92c with a hatched portion shown by C, and an outer peripheral shape 92d with a hatched portion shown by D. Include a program to move the planetary cutter 22 along. At the same time, the arithmetic device 81 is loaded with a selection circuit for arbitrarily selecting the above five types of programs,
If necessary, one of the five types of excavation cross sections can be arbitrarily selected, and thus the effect of overcut as described below can be obtained.

For example, if the excavation cross section program that matches the outer peripheral shape 92 of the skin plate 1 is selected and the excavation cross section program that matches the outer peripheral shape 92a is selected during excavation, the upper earth and sand of the skin plate 1 becomes It will be excavated beyond the perimeter (overcut).

When the excavation proceeds in this state, a cross-sectional space corresponding to the hatched portion A is formed in the upper part of the skin plate 1, and the friction resistance between the skin plate 1 and the earth and sand at this portion is reduced.
On the other hand, since the lower part of the skin plate 2 is still in contact with the earth and sand, the difference between the frictional resistance above the skin plate 1 and the frictional resistance below the skin plate 1 gradually increases. For this reason, the shield machine tries to escape to the side with the smaller frictional resistance, that is, the upper side, and as a result, the propulsion direction of the shield machine gradually rises.

In this way, the shield machine tries to change the direction to the overcut direction, so that the outer peripheral shape 92 shown in FIG.
By arbitrarily selecting the excavation section program that matches a to 92d, the advancing direction of the shield machine can be easily changed up, down, left and right, and excavation in a sharp curve is also possible. In addition, if a program that allows each of the four corners to be overcut is installed, it is possible to easily perform posture re-establishment control for rolling (the inclination of the shield machine with respect to the horizontal or vertical line).

Next, a second embodiment will be described with reference to FIGS. 14 and 15. Here, the rotary wheel drive device 26 in the above embodiment is used.
Instead, the rotary wheel 15 is driven to rotate by the hydraulic cylinder 40.

Specifically, the abdominal plate 2a of the cutting wheel 2 is provided with a cylinder support column 41.
Cylinder coupling brackets 421 and 422 are provided on the outer periphery of the end portion of 15, and both ends of the hydraulic cylinder 40 are rotatably coupled to the brackets 421 and 422, respectively.

With such a structure, the rotating wheel 15 can be driven in the forward and reverse directions by expanding and contracting the hydraulic cylinder 40. In the case of this embodiment, the rotation range of the rotary wheel 15 is narrowed, but there is an advantage that the structure is very simple. As the drive control system in this embodiment, a hydraulic cylinder controller (servo valve) may be used as the rotary wheel drive geared motor controller 83 in FIG.

The shield construction method and the shield machine according to the present invention are not limited to the above embodiments, and the following aspects can be taken as examples.

(1) In the present invention, the number of planetary cutters is not limited, and one or three or more planetary cutters may be provided depending on the case.

(2) Although the cutting wheel (large rotating body) 2 and the center cutter rotate integrally with each other in the above embodiment, they may be separately driven to rotate.

(3) In the above embodiment, the rotational displacement amount of the rotary wheel (small rotary body) 15 is constantly detected and calculated. For example, the rotational speeds of the cutting wheel 2 and the rotary wheel 15 are set in advance in accordance with the excavated sectional shape. Alternatively, control may be performed such that the angle is periodically corrected during excavation.

〔The invention's effect〕

As described above, according to the shield construction method of the present invention, the central circular portion on the front surface in the propulsion direction is excavated by the rotation of the center cutter, and the outer peripheral portion thereof revolves around the first axis while rotating the planetary cutter. By revolving around the axis of, it is possible to excavate into a free shape, and thus it is possible to continuously excavate a tunnel having a desired sectional shape, not limited to a circular shape. Moreover, only by appropriately changing the revolution angle of the planetary cutter around the second axis with respect to the revolution angle of the second axis around the first axis, the revolution locus of the planetary cutter around the first axis, that is, the excavated cross-sectional shape. Can be changed easily.

Further, according to the shield machine of the present invention, the center cutter that rotates about the first axis and the small rotating body that revolves about the first axis revolves about the second axis and about the third axis. Due to the planetary cutter that rotates, it is possible to obtain a desired excavation cross-sectional shape not only in a circular shape but with a simple structure.
The excavation cross-sectional shape can be easily changed only by changing the drive control contents of the large rotating body and the small rotating body. In addition, the mechanical load on the rotation axis of the planetary cutter is small.

[Brief description of drawings]

1 is a front view of a shield machine according to a first embodiment of the present invention, FIG. 2 is a sectional view taken along line II-II in FIG. 1, and FIG. 3 is a sectional view taken along line III-III in FIG. Fig. 4 is a sectional view taken along line IV-IV in Fig. 2, Fig. 5 is a sectional view taken along line VV in Fig. 2, Fig. 6 is a sectional view taken along line VI-VI in Fig. 2, and Fig. 7 shows a planetary cutter. A cross-sectional view corresponding to FIG. 5 showing a state on a diagonal line, FIG. 8 a cross-sectional view corresponding to FIG. 5 showing a state where the planetary cutters are on both sides, and FIG. 9 a drive control provided in the shield machine Block diagram showing the hardware configuration of the system, FIGS. 10 to 13 are diagrams showing examples of excavation cross-sectional shapes set in the shield machine, FIG. 14 is a sectional front view of the shield machine in the second embodiment, 15 is a sectional view taken along line XV-XV in FIG. 14, FIG. 16 is a sectional side view of a conventional shield machine, and FIG. 17 is a sectional view taken along line XVII-XVII in FIG. 2 ... Cutting wheel (large rotating body), 10 ... Wheel driving geared motor (first driving means), 15 ... Rotating shaft (small rotating body), 21 ... Planetary cutter driving geared motor (third driving means), 22 ... Planetary cutter, 24 ... Rotating wheel drive geared motor (second driving means), 30 ... Face plate (center cutter), 311, 312 ... Cutter bit (center cutter), 80 ... Cutting wheel rotational position detection 81 (comprising drive control system), 81 ... Arithmetic unit (comprising drive control system), 82 ... Comparator (comprising drive control system), 83 ... Geared motor controller for rotating wheel drive (comprising drive control system) , 84 ... Rotating wheel rotation position detector (constitutes drive control system).

Claims (2)

[Claims] 1. A shield construction method for excavating by rotating a cutter about a predetermined axis and propelling the cutter in a direction substantially parallel to the axis, while rotating the center cutter around the first axis and at the same time as the first The second that revolves around the axis
The orbit of the planetary cutter around the axis of, and the revolution angle of the second axis around the first axis so that the planetary cutter revolves around the first axis while drawing a locus according to the desired cross-sectional shape. A free-section shield for controlling the revolving angle of the planetary cutter about the second axis with respect to and for rotating the planetary cutter about a third axis parallel to the first axis and the second axis. Construction method. 2. A propelling means for propelling the entire apparatus, a center cutter rotating about a first axis substantially parallel to the propelling direction, a large rotating body rotating about the first axis, and a large rotating body and First driving means for rotationally driving the center cutter, a small rotating body attached to the large rotating body so as to be rotatable around a second axis parallel to the first axis, and the small rotating body is rotationally driven. Second drive means, a planetary cutter attached to the small rotating body so as to be rotatable about a third axis parallel to the first axis and the second axis, and a third cutter for rotationally driving the planetary cutter. And a drive control system for controlling the drive of the large rotating body and the small rotating body so that the planetary cutter revolves around the first axis while drawing a locus according to a preset cross-sectional shape. A free-section shield machine characterized by that.