JPH03122397A - Free cross section shield machine - Google Patents

Abstract

PURPOSE:To excavate a gateway of desired configuration by providing a rotor with a sliding member capable of sliding in the radial direction and a subcutter, the rotor having a main cutter mounted thereto, and also providing both a driving conversion mechanism for driving the sub-cutter and a slide control means. CONSTITUTION:A rotor 2 having the main cutter 3 of a shield main body 1 mounted thereto is provided with a sliding member 5 capable of sliding in the radial direction and a sub-cutter 4. A driving conversion mechanism C for converting rotation of the rotor 2 into that of the sub-cutter 4, and a control means for controlling actuation of the sliding member 5 are provided. The center portion of a working face i.e., the front face of excavation is excavated by driving of the main cutter 3, and during rotation of the main cutter 3 the outer peripheral portion of the center portion is excavated along the locus of revolution of the sub-cutter 4 by the actuation control means of the sliding member 5 and the driving conversion mechanism C. A tunnel of desired cross section is thus excavated.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a free-section shield machine that can continuously excavate tunnels of any desired cross-sectional shape, not just circular ones.

[Conventional technology]

Conventionally, various types of shield machines as described above have been proposed and put into practice. Generally, a cutter placed on the front of the shield machine body is rotated around the central axis of the shield machine to excavate the front face in the propulsion direction of the shield machine, and the shield machine is propelled by the excavated amount to create a segment ring. It is used to dig deeper by adding .

Further, Japanese Patent Application Laid-Open No. 59-102090 discloses an enlarged shield construction method for forming enlarged diameter sections such as retreat sections and station sections in a section of a tunnel excavated by the above-mentioned shield machine.

[Problem to be solved by the invention]

Conventional shield construction methods and shield machines excavate tunnels by rotating the front cutter, so the cross-sectional shape of the excavation is limited to a circle, and it is difficult to excavate tunnels with other irregular cross-sectional shapes. On the other hand, most of the cross-sectional shapes actually required for sewers, power lines, subway tunnels, etc. are other than circular, so conventionally, excavations with large circular cross-sections that include such irregular cross-sectional shapes have been carried out. Therefore, extra excavation work and disposal of the excavation waste are required. Such extra work has a greater impact on tunnel construction costs as the diameter of the cross section becomes larger, such as in subway tunnels, and is a constraint when applying the shield construction method.

To solve this problem, the invention disclosed in the above-mentioned publication first excavates a tunnel with a normal diameter and assembles segment rings, then removes the segment ring in the target area and performs special excavation work in the radial direction. The method is to partially form an enlarged diameter portion, and it is not to continuously excavate a cross section of a desired shape other than a circle.

SUMMARY OF THE INVENTION In view of the above circumstances, an object of the present invention is to provide a shield machine that can continuously excavate a tunnel having a desired cross-sectional shape, not just a circular one.

[Means to solve the problem]

The present invention includes a shield machine main body, a rotary body rotatably supported by the shield machine body so as to be rotatable around an axis extending in the propulsion direction, and a main cutter fixed to the front surface of the rotary body.
a main cutter driving means for rotationally driving the main cutter and the rotating body; a slide member attached to the rotating body so as to be slidable in a radial direction with respect to the rotating body; and a slide member rotatably attached to the sliding member. a sub-cutter, a drive conversion mechanism provided on the rotating body and converting rotation of the rotating body into rotation of the sub-cutter; and an operation control means for controlling the sliding operation of the slide member so that the slide member rotates while excavating (claim 1).

The present invention also provides a shield machine main body, a rotating body rotatably supported by the shield machine main body so as to be rotatable around an axis extending in the propulsion direction, a main cutter fixed to the front surface of the rotary body, and a main cutter and a main cutter driving means for rotationally driving the rotating body; a slide member attached to the rotating body so as to be slidable in a radial direction with respect to the rotating body; a sub-cutter rotatably attached to the sliding member; a sub-cutter drive means provided on the rotating body to rotationally drive each sub-cutter; and a slide member configured to rotate the sub-cutter while excavating a desired excavation area around the excavation area of the main cutter while the main cutter is rotating. and an operation control means for controlling the slide operation (claim 2).

[For production]

According to the above configuration, the main cutter is rotationally driven by the main cutter driving means, so that the central portion of the face, which is the front surface of the excavation, is excavated. Furthermore, during the rotation of the main cutter, the slide member slides in the radial direction with respect to the main cutter under the control of the operation control means, so that the sub cutter revolves drawing a unique locus, and the drive according to claim 1 By rotationally driving the sub-cutter by the action of the conversion mechanism or by the action of the sub-cutter rotation driving means according to claim 2, the outer peripheral portion of the face is excavated, and the entire excavation is performed in a desired cross-sectional shape.

〔Example〕

Embodiments of the present invention will be described below based on the drawings.

First Embodiment (Figs. 1 to 5) The shielding machine shown in Figs. A cutter casing (rotating body) 2 is provided at the left end (in FIG. 2).

On the front side of this cutter casing 2, there is a main cutter (cutter arm) 3 which is cross-shaped in front view as shown in FIG.
is fixed. This main cutter 3 has multiple blades 3.
a is provided, and the tips of the main cutter 3 are connected to each other by a cutter ring 6.

A plurality of (four in total in this embodiment) sub-cutters 4 having blades 4a on the front surface are arranged near each tip of the main cutter 3, and these sub-cutters 4 are cut through a slide member 5. It is supported by the outer circumference of the cutter casing 2. Further, each tip of the main cutter 3 is provided with a notch 3b to avoid interference with the sub-cutter 4.

As shown in FIG. 2, the rear end of the cutter casing 2 is connected to a partition wall 1a provided on the inner surface of the skin plate 1.
is supported via a large bearing 7. This large bearing 7 is
It supports radial load, thrust load, and moment load, and the cutter casing 2 is rotatably supported by this large bearing 7 around the central axis (axis extending in the propulsion direction) G of the skin plate 1. . Further, a ring gear 8 having internal teeth is fixed to the rear surface of the partition wall 1a.

In addition, in FIG. 2, only one sub-cutter 4 is shown, and illustration of other sub-cutter 4 is omitted. In addition, in the same figure, 48 is a chamber lb located at the front of the skin plate 1.
This is a seal to prevent the dirt inside from flowing backwards.

At the rear of the cutter casing 2, the skin plate 1
A retainer plate 40 is fixed to a bracket 1c provided on the inner wall surface of the cutter drive motor 41, and a cutter drive motor (main cutter drive means) 41 is fixed to the retainer plate 40. A pinion 42 is fixed to the drive shaft of the cutter drive motor 41, and a large gear 43 is fixed to the rear end of the cutter casing 2, and the two are meshed. Therefore, the cutter casing 2 and the main cutter 3 are rotationally driven as a unit by the operation of the cutter drive motor 41.

FIG. 3 shows the internal structure of the cutter casing 2 and slide member 5. As shown in FIG. First, in this structure, the drive conversion mechanism C that converts the rotation of the cutter casing 2 into the rotation of the sub-cutter 4 will be explained.

The slide member 5 includes a hollow slide pipe 9,
It has a double structure consisting of a hollow rod 10 inside this slide pipe 9, and both are fixed together. and,
The slide pipe 9 is supported by the cutter casing 2 via a slide bearing 11, and the entire slide member 5 is movable in the radial direction (direction of arrow A in FIGS. 1 to 3) with respect to the cutter casing 2. It has become.

Inside the hollow rod 10, an intermediate rotating shaft 12 and a hollow rotating shaft 13 are rotatably housed.

A base end (lower end in FIG. 3) of the intermediate rotating shaft 12 is connected to the hollow rotating shaft 13 by a spline 14 so as to be non-rotatable and slidable relative to the hollow rotating shaft 13. Also, the tip (third
The upper end (in the figure) is rotatably supported by a bearing 15 fixed to the cutter casing 2, and a bevel gear 16 is fixed to the inner part of this support part.

On the other hand, a bearing 17 is fixed to the tip of the cutter casing 2, and a rotating shaft 18 of the sub-cutter 4 is rotatably supported by the bearing 17. The bevel gear 16 is attached to the rear end of the rotating shaft 18. A bevel gear 19 that meshes with is fixed.

A hook gear 20 is fixed to the base end of the hollow rotating shaft 13, and a portion further outside the hook gear 20 is connected to the cutter casing 2.
It is rotatably supported by a bearing 21 fixed to a bracket 2a.

On the other hand, inside the cutter casing 2, a sub-cutter drive shaft 23 extending in the shield machine propulsion direction is rotatably supported via a bearing 22, and a front end portion of the sub-cutter drive shaft 23 engages with the bevel gear 20. A bevel gear 24 is fixed. The rear end of the drive shaft 23 protrudes outside the cutter casing 2, and a sub-cutter rotation pinion 25 as shown in FIG. 2 is fixed to this protruding end. It is meshed with the ring gear 8.

As mentioned above, since this ring gear 8 is fixed to the skin plate 1 side, when the cutter casing 2 rotates, the sub-cutter rotation pinion 25 that meshes with the ring gear 8 rotates, and the rotation sequentially rotates the sub-cutter rotation pinion 25. It is transmitted to the rotation shaft 18 of the sub-cutter 4 through the drive shaft 23, bevel gears 24, 20, hollow rotation shaft 13, intermediate rotation shaft 12, and bevel gears 16 and 19, and the sub-cutter 4 rotates integrally with this rotation shaft 18. I will do it.

Next, in the structure shown in FIG. 3, means for sliding the slide member 5 in the radial direction will be explained.

The base end of the hollow rod 10 of the slide member 5 is connected to a hydraulic cylinder 2 fixed to the cutter casing 2 with a pin 26.
It is housed in 7. A protrusion 27a that protrudes inward is formed at the tip of the hydraulic cylinder 27, and a protrusion 1 that protrudes outward is formed at the tip of the hollow rod 10.
0a is formed, a pull side pressure chamber 28 is formed between both protrusions 10a and 27a, and a push side pressure chamber 29 is formed between the protrusion 10a and the bottom wall of the hydraulic cylinder 27. There is. Then, by supplying pressure oil to the pull side pressure chamber 28 through the hydraulic pipe 30, the hollow rod 10 and the slide pipe 9 are integrated into the cutter casing 2, and conversely, the push side pressure chamber By supplying pressure oil to the cutter casing 29 through the hydraulic pipe 31, the hollow rod 10 and the slide pipe 9 project together from the cutter casing 2.

FIG. 4 shows an example of a hydraulic circuit for supplying pressure oil into the hydraulic chambers 28, 29.

In the figure, 32 is a rotary joint also shown in FIG. 2, 33 is a servo valve, 34 is a tank, 35 is a hydraulic pump, and 36 and 37 are switching solenoids. Here, if you want to hold the slide member 5 in a fixed position, shift the servo valve 33 to the position shown in the figure, and use the solenoid 36 to retract the slide member 5 and the solenoid 37 to push the slide member 5 out. It is sufficient to excite each of them.

Furthermore, a drive control system (operation control means) as shown in FIG. 5 is provided inside this shield machine, and the supply of the pressure oil is controlled by this drive control system. .

In the figure, a main cutter rotational position detector 90 sets the reference rotational position of the main cutter 3, that is, the reference rotational position of the cutter casing 2, to an appropriate position (for example, the position shown in FIG. 1).
is determined, and the amount of rotational displacement (for example, angle) of the main cutter 3 with respect to this reference rotational position is detected.

The hollow rod movement amount detector 94 appropriately determines the reference position of the hollow rod 10 in the slide member 5 and detects the actual amount of expansion and contraction of the hollow rod 10 from this reference position, and is composed of a potentiometer or the like. There is. In addition,
As the reference position, for example, the position of the hollow rod 10 when the sub cutter 4 is in the position shown in FIG. 1 may be set.

The calculation device 91 has a built-in program that calculates the amount of movement of the hollow rod 10 necessary for the amount of rotational displacement of the main cutter 3 when the purpose is to obtain a predetermined excavation cross section. Main cutter rotation position detector 9
The necessary amount of movement of the hollow rod 10 is instantaneously calculated for the amount of rotational displacement of the main cutter input from 0. The contents of the calculation will be described in detail later.

The comparator 92 compares the movement amounts input from the arithmetic device 91 and the hollow rod movement amount detector 94, and causes the hollow rod controller 93 to "protrude" so that the two are equal.
Alternatively, it gives a command to "immerse" and then gives a command to stop when the difference between the two disappears.

The hollow rod controller 93 controls the actual amount of movement of the hollow rod 10. That is, the control equipment type included in the hydraulic circuit shown in FIG. 4 is the hollow rod controller 9.
This corresponds to 3.

In addition, in FIG. 2, 45 is a screw conveyor that carries out the excavated earth and sand in the chamber 1b backward, and 46 is a shield jack that propels the shield machine by taking reaction force from segments 47 that are sequentially laid on the inner wall of the tunnel. .

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

First, by operating the cutter drive motor 41 in the skin plate 1, the pinion 42 fixed to its drive shaft and the large gear 43 rotate together.
The entire cutter casing 2 to which 3 is fixed rotates. As the cutter casing 2 rotates, the main cutter 3 at the front rotates to excavate the central portion of the face, and the sub-cutter 4 and its entire drive mechanism also revolve around the central axis 0.

Further, as mentioned above, the ring gear 8 is connected to the skin plate 1 side and remains fixed even while the cutter casing 2 is rotating, so each sub-cutter driving pinion 25 that meshes with the ring gear 8 is connected to the inner part of the ring gear 8. It rotates while revolving around the circumference. This sub-cutter driving binion 25
Since the rotation is transmitted to the rotating shaft 18 of each sub-cutter 4 by the mechanism explained in FIG. 3 above, each sub-cutter 4 is rotationally driven at a predetermined rotation speed.

On the other hand, in the drive control system, the calculation device 91 first calculates the amount of movement of the hollow rod 10 necessary to obtain a desired cross-sectional shape with respect to the rotational position of the main cutter 3, and calculates this amount of movement and the actual amount of movement. Based on the comparison, movement commands and stop commands for the hollow rod 10 are issued to the hollow rod controller 93 from time to time, and the sliding operations of the sub-cutter 4 and the slide member 5 are controlled so that a desired excavation cross section is obtained.

To explain the details of the control in detail, for example, as shown in FIG. The distance from the central axis G to the sub-cutter 4 (i.e., the revolution radius)
, thereby expanding the excavation area by the sub cutter 4 to a part of the corner. Conversely, when the sub-cutter 4 is located at a position corresponding to the midpoint of each side of the square skin plate 1, the hollow rod 10 is recessed into the cutter casing 2,
The distance from the central axis G to the sub cutter 4 is shortened. By such control, the sub-cutter 4 revolves while drawing a locus according to a desired excavation shape (here, a substantially rectangular shape).

Therefore, by driving the cutter casing 2 and sub-cutter 4 rotationally by the cutter drive motor 41 and propelling the entire shield machine by the operating force of the shield jack 47, the central circular portion is excavated by the main cutter 3 rotating at the center. At the same time, the outer peripheral portion can be excavated by the sub-cutter 4 which revolves around the tunnel while drawing a unique locus and rotates on its own axis, and a tunnel having a desired cross-sectional shape as a whole can be excavated.

The earth and sand excavated in this way is taken into the chamber 1b at the front of the skin plate 1, and is transferred to the screw conveyor 4.
5, and then finally transported to the ground by a belt conveyor (not shown) or the like.

According to such a shield machine, a tunnel having a desired cross-sectional shape can be continuously and easily excavated by the main cutter 3 fixed to the cutter casing 2 and the sub-cutters 4 arranged around the main cutter 3.

Moreover, in this shield machine, since the sub-cutter 4 is directly slid in the radial direction, that is, in the direction of the revolution radius, calculation of the revolution radius is easy, and a desired excavation shape can be obtained with simple control.

Further, since both the rotational drive mechanism and the slide mechanism of the sub-cutter 4 are housed in the single cutter casing 2, there is an advantage that the degree of freedom in arranging the screw conveyor 45 and the like is increased. In particular, since the earth and sand in the chamber 1b accumulates in the lower part thereof, there is a great advantage that the earth and sand inlet of the screw conveyor 45 can be installed in the lower part as shown in FIG.

Furthermore, in this shield machine, both the cutter casing 2 and each sub-cutter 4 are driven by the cutter drive motor 41, which is a single drive source, so that the above effects can be obtained with a simple and low-cost structure. can.

In addition, in this shield machine, the drive control system controls the rotational drive of the rotating member so that the sub-cutter 4 draws a desired orbital trajectory, so the calculation device 91
By simply converting the program to be incorporated into the
Various excavation cross-sectional shapes can be easily obtained.

Moreover, even better effects can be obtained by performing so-called overcut using such a function. This overcut will be explained based on FIG.

In the figure, areas J, L, and M are overcut zones indicated by hatching on the outside of the outer periphery 1' of the skin plate 1. During normal excavation, the sub cutter 4 is operated by the skin plate 1 by a program built into the computing device 91.
However, in this case, in addition to the program for realizing the above-mentioned movement, the calculation device 91 is controlled to move along the outer circumferential shape of the skin plate 1 and the outer circumferential shape 96a, which is the outer circumferential shape of the skin plate 1 plus the area J. A program for moving the sub-cutter 4 along the outer circumferential shape 96b1 including the area K, an outer circumferential shape 96C1 including the area M, and a program for moving the sub-cutter 4 along the outer circumferential shape 96d including the area M are incorporated. . At the same time, a selection circuit for arbitrarily selecting one of the five types of programs described above is added to the arithmetic unit 91, so that one of the five types of excavation cross sections can be arbitrarily selected as required. With such a configuration, it is possible to obtain the effect of overcutting as described below.

For example, if a normal excavation cross-section program is selected and excavation is being performed, and this program is switched to an excavation cross-section program that matches the outer peripheral shape 96a, the skin plate 1
The earth and sand that protrudes upward from the top side will also be excavated (
overcut).

If excavation is continued in this state, a cross-sectional space corresponding to the region J above the skin plate 1 is formed, and the frictional resistance between the skin plate 1 and the earth and sand in this part is reduced. On the other hand, since the lower part of the skin plate 1 is still in contact with earth and sand, the difference between the frictional resistance at the upper part of the skin plate 1 and the frictional resistance at the lower part of the skin plate 1 gradually increases. the result,
The shield machine tries to escape to the upper side where there is less frictional resistance, and the direction of propulsion of the shield machine gradually points upward.

In this way, the shield machine tries to change its direction in the direction of the overcut, so the outer peripheral shapes 96a to 9 in FIG.
By appropriately selecting the excavation cross-section program that corresponds to 6d, the advancing direction of the shield machine can be easily changed vertically and horizontally, making it possible to excavate sharp curves. Also,
By incorporating a program that can overcut a portion of each of the four corners, posture righting control against rolling can be easily performed.

Second Embodiment (FIGS. 7 and 8) In the above embodiment, the sliding operation of the slide member 5 is controlled by hydraulic pressure, but here, a guide cam 50 is arranged inside the cutter casing 2, and the guide cam 50 is arranged inside the cutter casing 2. The cam 50 specifies the orbit of the sub-cutter 4.

Specifically, in FIG. 7, the central part of the holding plate 40 is
The rear end of a fixed shaft 51 extending in the direction of propulsion of the shield machine is fixed, and the guide cam 50 is fixed to the front end of this fixed shaft 51. That is, this guide cam 50 is fixed to the skin plate 1 side. A bracket 52 is fixed to the inner wall of the cutter casing 2, and a bearing 53 fixed to the bracket 52 allows the fixed shaft 51 to
The front end of is supported. That is, while the cutter casing 2 is rotating, the bearing 53 moves on the circumferential surface of the fixed shaft 51.
will slide.

The guide cam 50 has opposing guide grooves 54 having a U-shaped cross section at the front and rear (left and right in FIG. 7). The shape of the guide groove 54 when viewed from the front, that is, the shape shown in FIG. 8, is set to correspond to a desired excavation shape.

On the other hand, regarding the slide member 5, a slide pipe 9 and a hollow rod 10 as shown in the above embodiments are used.
Instead of the double-structure structure, a structure with a single-structure slide pipe 9' is used. This slide pipe 9' is slidably supported on the cutter casing 2 side via a slide bearing 11, and a single intermediate rotating shaft 12 is rotatably supported by this slide pipe 9'. A base end (lower end in FIG. 7) of the intermediate rotating shaft 12 is coupled to the bevel gear 20 via a spline 57 so as to be non-rotatable and slidable.

A mounting bracket 55 is fixed to the base end of the intermediate rotating shaft 12, and rollers 56 are rotatably mounted on the front and rear (left and right in FIG. 7) of the distal end of the mounting bracket 55. They are respectively fitted into the guide grooves 54.

According to such a shield machine, the roller 56 and the guide groove 5 are rotated by operating the cutter drive motor 41 to rotationally drive the cutter casing 2 in the same manner as in the embodiment described above.
The slide member 5 and the sub cutter 4 remain engaged with each other.
revolves. Therefore, guided by the guide groove 54, the slide member 5 and the sub cutter 4 revolve while drawing a locus corresponding to the shape of the guide groove 54, thereby creating a tunnel having a desired shape, that is, a shape corresponding to the shape of the cam 50. to be excavated.

According to the apparatus of this embodiment, a desired excavation shape can be obtained simply by providing the cam 50 of a specific shape without using any special control program or the like.

Further, in this embodiment as well, since the drive mechanism including the cam 50 is housed within the cutter casing 2, it is possible to save space within the shield machine.

Third Embodiment (FIG. 9) Here, a face plate-shaped cutter plate 60 is used as the main cutter instead of the arm-shaped main cutter 3 in the previous embodiment. This cutter plate 60 has
A plurality of blades 60a are provided, and at appropriate locations,
A slit 61 is provided for introducing the earth and sand in front into the chamber 1b shown in the above embodiment, and the sub cutter 4
There is a notch 6 near the cutter 4 to avoid interference with the cutter 4.
2 is provided.

As shown in this embodiment, in the present invention, the shape of the main cutter may be set as appropriate regardless of the specific shape.

Fourth embodiment (FIG. 10) The first embodiment described above. In the second embodiment, a single cutter drive motor 4
1 drives both the main cutter 3 and the sub cutter 4, but in this embodiment, a sub cutter drive motor (sub cutter drive means) 70 separate from the cutter drive motor 41 is provided, and this sub cutter drive motor 70
Accordingly, each sub cutter 4 is driven separately from the main cutter 3.

In FIG. 10, at the rear end of the cutter casing 2,
A double gear 72 is rotatably supported via a bearing 71, and a front gear 72a of the double gear 72 is meshed with the sub-cutter driving pinion 25, which is also shown in the above embodiment. On the other hand, the sub-cutter drive motor 70 is fixed to the holding plate 40, and a pinion 73 fixed to its drive shaft is meshed with the rear gear 72b of the double gear 72.

According to such a shield machine, the cutter drive motor 41
When the cutter casing 2 is rotationally driven by the cutter casing 2, by operating the sub-cutter drive motor 70, the rotational force is transmitted to the double gear 72, which rotates separately from the cutter casing 2, and further rotates the sub-cutter drive pinion. 25. Therefore, with this structure, the rotation speed of the sub cutter 4 can be determined separately from the rotation speed of the main cutter 3 by appropriately setting the rotation speed of the sub cutter drive motor 70 and the reduction ratio by the double gear 72.

In addition, in this embodiment device, since the sub cutter 4 can be driven in either forward or reverse directions, the drive transmission mechanism C
There is no need to adjust the direction of rotation of the sub-cutter 4 when designing, etc., making the work easier. Furthermore, by changing the rotation direction of the sub-cutter 4, it is also possible to remove stones stuck between the outer periphery of the sub-cutter 4 and the skin plate 1, or to make corrections such as rolling during excavation. Become.

Note that the present invention is not limited to such embodiments, and may take the following embodiments as examples.

(1) In each of the above embodiments, the sub cutter 4 is arranged in front of the main cutter 3, but in the present invention, the sub cutter 4 may be arranged behind the main cutter 3. According to such a structure, first, the main cutter 3 excavates the earth and sand in the central part, and then the sub-cutter 4 excavates the surrounding part, so the area excavated by the sub-cutter 4 is the same as shown in the above embodiments. As shown in FIG.

(a) In general, the outer radius of the sub cutter 4 is smaller than the outer radius of the main cutter 3 (because it is set, the number of blades 4a attached to the sub cutter 4 is smaller than that of the main cutter 3).
One blade 4 is smaller than the number of blades 3a attached to the
The amount of work done by a is large. Therefore, if the load on the sub-cutter 4 is large, the blade 4a of the sub-cutter 4 will wear out before the blade 3a of the main cutter 3.

In this regard, with the shield machine in which the sub-cutter 4 is placed at the rear as described above, the excavation area is reduced and the earth and sand is loosened by the excavation by the main cutter 3, so the sub-cutter 4
The burden of
The life of the entire shield machine is extended.

(b) Compared to the main cutter 3, driving the sub-cutter 4 requires a more complicated mechanism, so by reducing the burden on the sub-cutter 4, the driving mechanism can be simplified, reducing costs and downsizing the shield machine. can be achieved.

(2) The shape of excavation by the shield machine of the present invention is not limited to the rectangular shape as in the above embodiments, but may include circular, oval, horseshoe, etc.
It is possible to obtain the desired excavation shape.

FIG. 11 shows the outer periphery 1' of the skin plate 1, a small circle 100 (-dotted chain line) that is the excavation cross-sectional shape obtained by rotating the main cutter 3, and the distance that passes most from the center of the small circle 100 to the center of the sub-cutter. Cutter casing 2 in a rough state
Great circle 1, which is the excavation cross-sectional shape obtained when rotating
01 (-dotted chain line), in this device, the orbit of the sub-cutter can be freely set within the range surrounded by the small circle 100 and the large circle 101.

In either case, good excavation can be performed by exchanging the excavation cross-section program of the calculation device 91 and using a skin plate having a cross-sectional shape corresponding to each excavation cross-sectional shape. For example, the figure shows the outer periphery 1' of the skin plate 1 having a rectangular cylinder shape, and as is clear from this figure, the outer circumferential shape of the skin plate 1 falls within the above-mentioned range. .

Similarly, Figure 3g12.13 shows an example in which the outer peripheral shapes of a horseshoe shape and an oval shape are kept within the above-mentioned range. In these cases as well, a skin plate having the above-mentioned horseshoe-shaped or oval-shaped outer circumferential shape may be used, and a calculation program, cam, etc. may be provided so that the orbit of the sub-cutter matches these shapes.

(3) In the present invention, as shown in FIG. 14, for example, it is possible to perform a continuous installation in which a plurality of skin plates 1 are stacked and integrated. In this case, in addition to the double installation shown in the figure, triple installation or quadruple installation is also possible. Further, as shown in FIG. 15, the same effect as described above can be obtained even if a single skin plate 1 is used and a plurality of excavation mechanisms are installed in this skin plate 1. .

(4) In the present invention, the number of sub-cutters and their positions do not matter, and they may be placed at appropriate locations depending on the soil quality.

〔Effect of the invention〕

As described above, the present invention rotates a main cutter and a rotating body, supports a sub-cutter on the rotating body via a slide member, and moves the slide member so that the sub-cutter draws a trajectory corresponding to a desired excavation shape. Since the tunnel is moved in the radial direction, the main cutter excavates the central circular part of the face, and the outer periphery is excavated by the sub-cutters that draw a unique trajectory, thereby creating a tunnel that has the desired cross-sectional shape as a whole. can be excavated freely. Moreover, since the sub-cutter is made to slide directly in the radial direction, that is, in the direction of the revolution radius, it is easy to set the sliding amount corresponding to the desired revolution radius of the sub-cutter, and the above effects can be obtained with simple control. There is an effect that can be done.

Furthermore, the shielding machine according to claim 1 is provided with a drive conversion mechanism that converts the rotation of the rotating body into rotation of the rotation shaft of the sub-cutter, so that both the main cutter and the sub-cutter can be driven by the same driving means. This has the effect of simplifying the structure and reducing costs.

Further, in the shielding machine according to claim 2, since the driving means for the main cutter and the driving means for the sub-cutter are provided separately, the rotational direction and rotational speed of the double-force vine can be set independently. This has the effect of allowing you to freely set the rotation speed suitable for digging.

[Brief explanation of drawings]

FIG. 1 is a front view of a shielding machine according to a first embodiment of the present invention, FIG. 2 is a sectional view taken along line mm in FIG.
Figure 4 is a circuit diagram of the hydraulic circuit installed in the shield machine.
Fig. 5 is a block diagram showing the drive control system installed in the shield machine, Fig. 6 is a front view showing the overcut area by the shield machine, and Fig. 7 is the main part of the shield machine in the second embodiment. 8 is a sectional view taken along the line ■-■ in FIG. 7, FIG. 9 is a front view of the shield machine in the third embodiment, and FIG. 10 is a drive of the sub-cutter of the shield machine in the fourth embodiment. A sectional view showing the structure, FIG. 11 is an explanatory view showing the orbital locus of the sub-cutter and the setting range of the outer peripheral shape of the skin plate, FIGS. 12 and 13 are explanatory views showing other examples of the outer peripheral shape of the skin plate, FIG. 14 is an explanatory diagram showing a state in which a plurality of skin plates are connected in series, and FIG. 15 is an explanatory diagram showing a single skin plate equipped with a plurality of excavation mechanisms. 1...Skin plate (shield machine body), 2...
Cutter casing (rotating body), 3...main cutter,
4...Sub cutter, 5...Slide member, 41...
- Cutter drive motor (rotating body drive means), 50... Guide cam (constituting operation control means), 60... Cutter plate (main cutter), 70... Sub cutter drive motor (sub cutter drive means), 90 ... Cutting wheel rotational position detector (constituting operation control means), 91
. . . Arithmetic unit (constituting the operation control means), 92 . . . Comparator (constituting the operation control means), 93 . Expansion/contraction amount detector (constituting the operation control means), C... Drive conversion mechanism, G... Central axis (axis extending in the propulsion direction) Fig. 1

Claims (1)

[Claims] 1. A shield machine main body, a rotating body rotatably supported by the shield machine main body around an axis extending in the propulsion direction;
A main cutter fixed to the front surface of the rotating body, a main cutter driving means for rotationally driving the main cutter and the rotating body, and a slide attached to the rotating body so as to be slidable in a radial direction with respect to the rotating body. a member, a sub-cutter rotatably attached to the slide member,
A drive conversion mechanism is provided on the rotary body and converts rotation of the rotary body into rotation of the sub-cutter, and the sub-cutter excavates a desired excavation area around the excavation area of the main cutter while the main cutter is rotating. and an operation control means for controlling the sliding operation of the slide member so that the slide member rotates while rotating. 2. A shield machine main body, a rotating body rotatably supported by the shield machine main body around an axis extending in the propulsion direction;
A main cutter fixed to the front surface of the rotating body, a main cutter driving means for rotationally driving the main cutter and the rotating body, and a slide attached to the rotating body so as to be slidable in a radial direction with respect to the rotating body. a member, a sub-cutter rotatably attached to the slide member,
a sub-cutter drive means provided on the rotary body to rotationally drive each sub-cutter; and a slide member configured to rotate the sub-cutter while excavating a desired excavation area around the excavation area of the main cutter while the main cutter is rotating. A free cross-section shield machine characterized by comprising: an operation control means for controlling the slide operation of the machine.