JPH08210089A - Shield machine - Google Patents

Abstract

PURPOSE: To simplify an operating mechanism by placing a copy cutter which is projected toward the outer peripheral surface of a cutter head by the operation of a single-acting cylinder and is retreated by the spring force of a compression coil. CONSTITUTION: High-pressure oil is supplied to the bottom side of a single-acting hydraulic cylinder 20 via hydraulic piping 21, and thereby a piston 20a is expanded to advance a support shaft 13 to cause a copy cutter 16 to project outwards from the outer peripheral surface 4a of a cutter head 4. As the cutter head 4 rotates, the natural ground around the cutter head 4 is drilled. To retreat the copy cutter 16 after the drilling is complete, the hydraulic tubing 21 of the single-acting hydraulic cylinder 20 is switched to the low pressure side and then the copy cutter 16 is retreated to an initial position along with the support shaft 13 by the spring force of a compression coil spring 15. The spring force of the compression coil spring 15 in this case is sufficient to retreat the copy cutter 16 to the initial position by overwhelming the weight of the spring and frictional forces even if the copy cutter device 10 is located beneath the cutter head 4.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shield machine, and more particularly to a shield machine having an improved copy cutter operating mechanism.

[0002]

2. Description of the Related Art Generally, in a shield machine, a cutter head is provided in a front portion of a shield body, and the cutter head is rotated to excavate a face and shield a segment to form a tunnel. There is.

By the way, in such a shield machine, a machine equipped with a copy cutter device which can be retracted and retracted from the outer peripheral surface of the cutter head in order to carry out over-digging is disclosed in, for example, Japanese Utility Model Laid-Open No. 59-1798, Japanese Utility Model Publication No. 59-1798. Sho 60-162194, Utility Model 3-122197, Utility Model 4-12
It is known from, for example, Japanese Patent No. 594.

FIG. 31 shows an example of this type of conventional copy cutter device. This copy cutter device 100
Is a double-acting hydraulic cylinder 102 provided on the outer peripheral portion of the cutter head 101, a support shaft 103 provided at the rod tip of the double-acting hydraulic cylinder 102, and the support shaft 103.
And a copy cutter 104 attached to the tip of the.

In such a copy cutter device 100, when high-pressure oil is supplied to the bottom side of the double-acting hydraulic cylinder 102 from the pipe 105, the support shaft 103 is advanced and the copy cutter 104 at the tip of the support shaft 103 is cut. Protruding from the outer peripheral surface of the head 101 to the position indicated by the chain line,
With the copy cutter 104 protruding, the cutter head 10
When 1 is rotated, the ground is dug. On the other hand, when over-digging is not performed, when high pressure oil is supplied to the rod side of the double-acting hydraulic cylinder 102 from the conduit 106, the support shaft 103 is retracted and the copy cutter 10 is moved.
4 is retracted from the outer peripheral surface of the cutter head 101.

On the other hand, as a copy cutter device used for a parent-child shield excavator in which a small-diameter child shield machine is arranged inside a large-diameter parent shield machine, for example, Japanese Patent Laid-Open No. 3-1
What is disclosed in Japanese Patent Publication No. 97791 is known. In the copy cutter device described in this publication, the child shield machine is provided with a copy cutter device having a very long protrusion stroke, and when the parent shield machine and the child shield machine are being dug integrally, the child shield machine and the parent shield machine It is configured to extend the copy cutter device to the outer periphery of the cutter head of the machine to carry out overcutting.

However, in such a copy cutter device, when the copy cutter device is used when the parent and child are integrally excavated, the protrusion amount of the copy cutter device from the outer peripheral surface of the child shield machine becomes extremely long, and The copy cutter has a cantilever structure outside the outer peripheral surface of the child shield machine. Therefore, in order to secure the strength that can withstand the load applied to the copy cutter, it is necessary to increase the diameter of the support shaft of the copy cutter and to increase the support length of the support shaft. Thus, there is a problem that the device becomes large and it is difficult to secure an installation space.

In order to deal with this problem, a copy cutter device as disclosed in FIG. 32 has been proposed. In this copy cutter device 107, the child shield machine 108 is provided with a copy cutter unit 111 including a copy cutter 109 and a double-acting hydraulic cylinder 110 for retracting the copy cutter 109, and the copy cutter unit 111 is provided with a child cutter head 112. A double-acting hydraulic cylinder 113 for unit movement provided on the side is configured to be moved forward and backward.

In this copy cutter device 107,
When excavating a large-diameter tunnel by advancing the parent and child together, as shown in FIG. 32, the unit cutter double-acting hydraulic cylinder 113 moves the entire copy cutter unit 111 to the parent shield machine 114 side. After that, the double-acting hydraulic cylinder 110 further causes the copy cutter 109 to project from the outer peripheral surface of the parent cutter head 115 to perform overdug.
On the other hand, when the child shield machine 108 is started from the inside of the parent shield machine 114 and the child shield machine 108 is excavating a small-diameter tunnel, as shown in FIG. After 113, the entire copy cutter unit 111 is pulled back to the slave shield machine 108 side, and then the double cutter hydraulic cylinder 110 causes the copy cutter 109 to project from the outer peripheral surface of the slave cutter head 112 to carry out excess digging.

[0010]

However, in the above-mentioned conventional copy cutter device 100 (FIG. 31), the double-acting hydraulic cylinder 102 is used to cause the copy cutter 104 to project and retract. 102
Two hydraulic pipes are required, one for each of the bottom side and the rod side, and a rotary joint must be provided for each hydraulic pipe from the shield machine body to the cutter head.
For this reason, the hydraulic piping is complicated and expensive, and there are problems that oil leakage at the rotary joint portion or failure of the rotary joint increases.

On the other hand, in the conventional copy cutter device 107 (FIGS. 32 and 33) in the parent-child shield machine, an extra double-acting hydraulic cylinder for moving the unit is additionally required. A total of four hydraulic pipes are required, one on the rod side and one on the rod side, which also has the same problem as described above.

The present invention has been made in view of the above problems, and an object thereof is to provide a shield machine capable of reducing the number of hydraulic pipes in a copy cutter device and simplifying its operating mechanism. It is what

[0013]

In order to achieve the above-mentioned object, the shield machine according to the present invention is, firstly, a shield machine having a cutter head at the front part of the shield body. It is characterized in that a copy cutter is provided on the outer peripheral surface of the cutter head so as to be projected by the operation of the driving means and retracted by a spring force.

In the invention having the first feature, when the overcutting is performed, the driving means is operated to cause the copy cutter to project from the outer peripheral surface of the cutter head, so that the cutter head is rotated by the rotation of the cutter head. The surrounding ground is excavated by the copy cutter. On the other hand, when the copy cutter is retracted after the over-digging is completed, the copy cutter is retracted from the outer peripheral surface of the cutter head by the spring force by releasing the operation of the driving means. In this way, when the drive means is a single-acting hydraulic cylinder, the hydraulic piping can be halved compared to the conventional double-acting hydraulic cylinder that is moved forward and backward, and thereby the rotary pipe provided in the middle of the hydraulic piping. There are few joints. Therefore, the operation mechanism of the copy cutter can be greatly simplified, and oil leakage from the rotary joint and the like can be reduced to improve reliability.

The shield machine according to the present invention is, secondly,
A large-diameter parent shield machine having an annular parent cutter head,
In a shield machine, which is a combination of a small-diameter child shield machine having a disk-shaped child cutter head, a parent copy cutter provided in the parent cutter head and a child copy cutter provided in the child cutter head, and the parent cutter head and The parent cutter head is provided in series in the radial direction of the child cutter head, and the child cutter head is provided with a driving means for causing the parent copy cutter to project from the outer peripheral surface of the parent cutter head via the child copy cutter, and the parent cutter. The head is provided with a spring for retracting the parent copy cutter from the outer peripheral surface of the parent cutter head.

In the invention having the second feature, when over-digging is carried out while the parent shield machine and the child shield machine are integrally excavated, the drive means is operated to operate the child copy cutter through the child copy cutter. By projecting the parent copy cutter from the outer peripheral surface of the parent cutter head, the ground around the parent cutter head is excavated by the parent copy cutter by the rotation of the parent cutter head and the child cutter head. On the other hand, when the parent copy cutter is retracted after the over-digging is completed, the parent copy cutter is retracted from the outer peripheral surface of the parent cutter head by the spring force by deactivating the drive means. In addition, when excavating the child shield machine independently, when operating the child shield machine by operating the drive means to project the child copy cutter from the outer peripheral surface of the child cutter head, The ground around the child cutter head is excavated by the child copy cutter. On the other hand, when the extra copy is completed and the child copy cutter is to be retracted, the child copy cutter is retracted from the outer peripheral surface of the child cutter head by the operation of the driving means in the opposite direction. In this way, similarly to the invention having the first feature, the operating mechanism of the copy cutter can be greatly simplified.

Thirdly, the shield machine according to the present invention comprises:
A large-diameter parent shield machine having an annular parent cutter head,
In a shield machine, which is a combination of a small-diameter child shield machine having a disk-shaped child cutter head, a base end portion of a parent copy cutter provided in the parent cutter head and a tip end portion of the child copy cutter provided in the child cutter head. And is provided so as to be connectable or disconnectable via a connecting means, and the child cutter head is provided with a driving means for projecting the parent copy cutter from the outer peripheral surface of the parent cutter head via the child copy cutter. It is a feature.

In the invention having the third feature, when over-digging is carried out while the parent shield machine and the child shield machine are integrally excavated, the drive means is operated to operate the child copy cutter. By projecting the parent copy cutter from the outer peripheral surface of the parent cutter head, the ground around the parent cutter head is excavated by the parent copy cutter by the rotation of the parent cutter head and the child cutter head. On the other hand, when the duplication is completed and the parent copy cutter is to be retracted, the parent copy cutter is coupled to the child copy cutter by the operation of the driving means in the reverse direction and is retracted from the outer peripheral surface of the parent cutter head. When the child shield machine is digging alone while the parent copy cutter and child copy cutter are disconnected, the drive means is operated to move the child copy cutter to the child cutter head. By projecting from the outer peripheral surface of the child cutter head, the ground around the child cutter head is excavated by the child copy cutter by the rotation of the child cutter head. On the other hand, when the extra copy is completed and the child copy cutter is to be retracted, the child copy cutter is retracted from the outer peripheral surface of the child cutter head by the operation of the driving means in the opposite direction. In this way, similarly to the invention having the first feature, the operating mechanism of the copy cutter can be greatly simplified.

In the invention having the second and third features, a spring for retracting the slave copy cutter from the projecting position may be provided, and the drive means may be a single-acting hydraulic cylinder. By doing so, the child copy cutter can be retracted by the spring force, and the operation mechanism of the copy cutter is further simplified. Also, this third
In the invention having the above feature, the drive means may be a double-acting hydraulic cylinder.

In the invention having the third feature, the connecting means is connected by advancing the child shield machine from a connected state of a base end portion of the parent copy cutter and a tip end portion of the child copy cutter. It may consist of a pin provided on either the parent copy cutter or the child copy cutter and a hook provided on the other so that the state is released. According to such a connecting means, when the child shield machine is started, the child shield machine advances to automatically disconnect (disconnect) the parent copy cutter and the child copy cutter. Therefore,
No special device or special work is required for releasing the connection, and the structure is simplified.

Further, the connecting means releases the connected state by rotating the child shield machine from the connected state of the base end portion of the parent copy cutter and the tip end portion of the child copy cutter. , A parent copy cutter or a child copy cutter, and a hook provided on the other.

Further, the connecting means is a wire for connecting the base end of the parent copy cutter and the tip of the child copy cutter, and the base end of the parent copy cutter and the child copy cutter are connected by this wire. It is also possible that the wire is pressed against the required edge portion and cut by advancing the child shield machine from the state of connection with the tip portion of the.

Further, it is preferable that the parent cutter head is rotatably supported on the parent shield machine body. With this configuration, the parent cutter head does not move in the front-rear direction with respect to the parent shield machine body. Therefore, for example, when the parent copy cutter and the child copy cutter are separated by advancing the child shield machine, the parent copy cutter and the parent cutter head are not dragged by the child shield machine to move forward, and the separation can be reliably performed. .

It is preferable that the base end portion of the parent copy cutter is positioned outside the outer peripheral surface of the child cutter head even when the parent copy cutter is most retracted.
By doing this, when the child shield machine starts from the parent shield machine, it is possible to avoid the parent copy cutter from interfering with the child shield machine regardless of the stroke position of the parent copy cutter. . In this way, it is possible to avoid the occurrence of the trouble that a part of the child shield machine is caught by the parent copy cutter and the child shield machine cannot start.

When the parent copy cutter and the child copy cutter are connected and the parent copy cutter is in the most retracted state, the tip portion of the child copy cutter is protruded by a predetermined amount outside the outer peripheral surface of the child cutter head. The child copy cutter has a stroke amount obtained by adding the predetermined protrusion amount to the stroke amount required for the parent copy cutter, and a stroke amount necessary for performing overdrilling by the child copy cutter. It is preferable to have a stroke of whichever is larger. As a result, it is possible to secure the amount of excess digging necessary when the parent and child are excavating.

The face plate of the parent cutter head, which corresponds to the tip portion of the child copy cutter protruding outward from the outer peripheral surface of the child cutter head in a state where the parent copy cutter and the child copy cutter are connected, is notched. Preferably. By doing this, when starting the child shield machine, it is possible to release the connection between the parent copy cutter and the child copy cutter and start by simply moving the child shield machine forward without shortening the child shield machine. Therefore, the starting work of the child shield machine can be simplified. Further, even if a trouble occurs in the driving means for shortening the child copy cutter, the worst situation in which the child shield machine cannot be started can be avoided.

Objects of the present invention will become apparent from the detailed description given below. However, while the detailed description and specific examples describe the most preferred embodiments, various modifications and variations within the spirit and scope of the invention will be apparent to those skilled in the art from the detailed description, and therefore, specific examples As described below.

[0028]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, specific embodiments of the shield machine according to the present invention will be described with reference to the drawings.

(First Embodiment) FIG. 1 shows a front view of a shield machine according to the first embodiment of the present invention, and FIG. 2 shows a longitudinal sectional view of the shield machine.

In the shield machine of the present embodiment, a plurality of shield jacks 2 for propelling the shield body 1 are arranged inside the cylindrical shield body 1, and the shield body 1 is provided at the front portion thereof. A disk-shaped cutter head 4 is provided which is rotated by driving the cutter head motor 3.

The cutter head 4 is provided with a plurality of spokes 5 extending from the center in the radial direction.
A large number of cutter bits 6 are attached to both sides of the cutting bit 6, and the cutting bits 6 excavate the face. The excavated earth and sand is taken into the chamber 8 in the front part of the shield body 1 through the earth and sand intake ports 7 opened between the spokes 5, and thereafter, the chamber 8 is provided with a screw conveyor whose front end is opened. It is conveyed backward by the soil device 9.

In the cutter head 4, a copy cutter device 10 is arranged along one spoke 5. As shown in FIGS. 3 and 4, the copy cutter device 10 includes a guide bush 11 fixed to the outer peripheral portion of the cutter head 4, and a support shaft is provided in the guide bush 11 via bearings 12a and 12b. 13 is slidably supported in the radial direction of the cutter head 4. As shown in FIG. 5, a spring seat 13a is provided at an intermediate portion of the support shaft 13 in a spring chamber 14 formed between the bearings 12a and 12b so as to project from the spring seat 13a. A compression coil spring 15 that urges the support shaft 13 in the backward direction is stretched between the bearing 12a and the bearing 12a. The spring seat 1
3a has a communication hole 13 for communicating the inside of the spring chamber 14 with the atmosphere.
b is drilled.

The small diameter portion 13 is provided at the tip of the support shaft 13.
c is formed, and a pair of copy cutters 16 are detachably attached to both sides of the small diameter portion 13c by a fixing tool 17. The copy cutter 16 has a tip 16a at its tip, and the tip 16a allows the ground around the cutter head 4 to be dug with the rotation of the cutter head 4.

The spokes 5 are provided on the base end side of the support shaft 13.
A single-acting hydraulic cylinder 20 is swingably supported via a trunnion 19 on a bracket 18 fixed to the inner side of the support shaft. A tip end portion of a piston rod 20a of the single-acting hydraulic cylinder 20 is supported by the support shaft via a ball joint 20b. It is pivotally supported at the base end of 13. Further, one end of a hydraulic pipe 21 is connected to the bottom side of the single-acting hydraulic cylinder 20. In addition,
The other end of the hydraulic pipe 21 is connected to a hydraulic pipe on the shield body 1 side via a rotary joint, and is connected to the bottom side of the single-acting hydraulic cylinder 20 from the shield body 1 side via these hydraulic pipes. Hydraulic pressure is supplied and discharged. A reference numeral 22 in FIG. 5 denotes a dust seal that prevents dirt, muddy water, or the like from entering the guide bush 11.

Next, the operation of the copy cutter device 10 having the above-mentioned structure will be described with reference to FIGS. 6 and 7.

First, in the case of excavating a tunnel without excessive digging by the copy cutter 16, the single-acting hydraulic cylinder 2
The hydraulic pipe 21 connected to the bottom side of 0 is set to the low pressure side. As a result, the support shaft 13 is retracted toward the center of the cutter head 4 by the spring force of the compression coil spring 15, and the copy cutter 16 attached to the tip end side of the support shaft 13 is as shown in FIG. On the cutter head 4
Is retreated inward from the outer peripheral surface 4a. Therefore, even if the cutter head 4 rotates, the ground around the cutter head 4 is not overexcavated. Since it is not necessary to supply high-pressure oil to the single-acting hydraulic cylinder 20 at this time, oil leakage does not occur from a rotary joint or the like provided in the middle of the hydraulic pipe 21.

Next, in the case of using the copy cutter 16 for overcutting, high-pressure oil is supplied to the bottom side of the single-acting hydraulic cylinder 20 through the hydraulic pipe 21. As a result, as shown in FIG. 7, the piston rod 20 a of the single-acting hydraulic cylinder 20 extends and the support shaft 13 advances, and the copy cutter 16 attached to the tip of the support shaft 13 is moved.
Are projected outward from the outer peripheral surface 4a of the cutter head 4.
In this way, as the cutter head 4 rotates, the copy cutter 1
6 excavates the ground around the cutter head 4.

When the over-digging is completed, the copy cutter 16
In order to retreat, when the hydraulic pipe 21 connected to the bottom side of the single-acting hydraulic cylinder 20 is switched to the low pressure side, the copy cutter 16 together with the support shaft 13 is shown in FIG. 6 by the spring force of the compression coil spring 15. Is retracted to the position where Here, as the spring force of the compression coil spring 15, even when the copy cutter device 10 is below the cutter head 4, the copy cutter 16 is retracted to the position shown in FIG. 6 by overcoming its own weight and frictional force. As much force f as possible is required. Therefore, the compression coil spring 15 is housed in the spring chamber 14 in a state of being contracted by f / k (k: spring constant) or more from its natural length when the copy cutter 16 is at the position shown in FIG. .

In this embodiment, the compression coil spring 15 for retracting the copy cutter 16 is provided in the guide bush 11, but a modification in which a tension spring is internally provided in the single-acting hydraulic cylinder is also possible. . That is, in this modified example, as shown in FIG. 8, the piston rod 20a of the single-acting hydraulic cylinder 20 'is formed hollow, and the tension spring 1 is formed in the piston rod 20a.
5'is housed. The tension spring 15 'has a base end fixed to the bottom side of the single-acting hydraulic cylinder 20' and a tip end fixed to the tip side of the piston rod 20a. The tension spring 15 'causes the piston rod 20a to constantly contract. Being energized.

Thus, when the bottom side of the single acting hydraulic cylinder 20 'is switched to the low pressure side, the copy cutter 16 is retracted to the position shown in FIG. 8 by the urging force of the tension spring 15'. On the other hand, if high pressure oil is supplied to the bottom side of the single-acting hydraulic cylinder 20 ′ via the hydraulic pipe 21,
The piston rod 2 resists the biasing force of the tension spring 15 '.
0a is extended, and the copy cutter 16 attached to the tip of the support shaft 13 is projected outward from the outer peripheral surface 4a of the cutter head 4, whereby over-digging is performed.

Further, since the tension spring 15 'is internally provided in the single-acting hydraulic cylinder 20' as in the modification, the compression coil spring 15 as in the present embodiment is not necessary, and therefore the support shaft of the modification is provided. Other modifications are possible in which 13 is omitted. That is, in this modification, as shown in FIG. 9, the copy cutter 16 is directly attached to the piston rod 20a of the single-acting hydraulic cylinder 20 'having the tension spring 15' therein.

(Second Embodiment) This embodiment is applied to a parent-child shield excavator in which a small-diameter child shield machine is arranged inside a large-diameter parent shield machine. FIG. 10 shows a vertical sectional view of a parent-child shield excavator according to the second embodiment.

In the shield machine according to the present embodiment, the child shield machine 24 is arranged in the parent shield machine 23. The parent shield machine 23 uses the parent shield jack 25 and the child shield machine 24 uses the child shield jack 26. It is configured to be moved back and forth respectively. An annular parent cutter head 27 is provided at the front of the parent shield machine 23, and a disc-shaped child cutter head 28 is provided at the front of the child shield machine 24. The parent cutter head 27 and the child cutter head 28 are connected by a detachable connecting means 29, and the child shield machine 24 is also provided.
It is adapted to be rotationally driven by a cutter head motor 30 provided therein.

In this embodiment, the copy cutter device is
Parent copy cutter 31 provided in the parent cutter head 27
And the child copy cutter 3 provided in the child cutter head 28
2 and.

An enlarged sectional view of this copy cutter device is shown in FIG.
1 and an operation explanatory view are shown in FIG. 12, respectively. As shown, the parent copy cutter 31 and the child copy cutter 32
Is arranged so as to be coaxial when excavating as a parent and child. A support shaft 33 is provided at the base end portion of the parent copy cutter 31, and the support shaft 33 is attached to the parent cutter head 2.
It is supported by a guide bush 33 </ b> A fixed inside 7. On the other hand, a support shaft 34 is provided at the base end of the child copy cutter 32.
And a support shaft 34 thereof is supported by a guide bush 35 fixed in the child cutter head 28.

Support shaft 33 on the side of the parent copy cutter 31
Is urged in the retracting direction (downward in FIG. 11) by a compression coil spring 36 inserted in the guide bush 33A. Further, a tip end portion of a piston rod 37a of a double-acting hydraulic cylinder 37 is attached to a base end portion of the support shaft 34 on the child cutter head 28 side, and a hydraulic pressure is applied to a rod side and a bottom side of the double-acting hydraulic cylinder 37, respectively. Hydraulic pressure is supplied through the pipes 38 and 39. In the retracted state of the parent copy cutter 31 and the child copy cutter 32, the base end of the support shaft 33 and the tip of the child copy cutter 32 are opposed to each other with a required gap.

When excavating a large-diameter tunnel in the parent-child shield excavator having the above-described structure, the parent shield machine 23 and the child shield machine 24 are connected to each other, and the parent cutter head 2 is used.
7 and the child cutter head 28 are connected by a connecting means 29, the cutter head motor 30 drives the parent cutter head 27 and the child cutter head 28 to rotate simultaneously, and the parent shield jack 25 causes the parent shield machine 23 and the child shield. The machine 24 and the machine 24 are simultaneously propelled. When excavating during excavation of this large-diameter tunnel, high-pressure oil is supplied to the bottom side of the double-acting hydraulic cylinder 37 via a hydraulic pipe 39. As a result, the support shaft 33 on the parent cutter head 27 side is pressed and moved forward via the support shaft 34 on the child cutter head 28 side, and the parent copy cutter 31 attached to the tip of the support shaft 33 causes the parent cutter head. Two
Excavation of the ground around 7 is carried out. Further, in the case where the parent copy cutter 31 is to be retracted after the over-digging is completed, when high pressure oil is supplied to the rod side of the double-acting hydraulic cylinder 37 via the hydraulic pipe 38 to contract the piston rod 37a,
As the support shaft 34 on the child cutter head 28 side is retracted, the support shaft 33 on the parent cutter head 27 side is retracted to a required storage position by the compression coil spring 36.

On the other hand, when the excavation of the large-diameter tunnel is completed and the small-diameter tunnel is excavated continuously to this large-diameter tunnel, the excavation is performed between the parent shield machine 23 and the child shield machine 24 and between the parent cutter head 27 and the child shield machine. In the state where the connection with the cutter head 28 is released, the cutter head motor 30 rotationally drives the child cutter head 28, and the child shield jack 26 starts the child shield machine 24 from within the parent shield machine 23. When the child shield machine 24 is started, as shown in FIG. 12, a required space is provided between the support shaft 33 on the parent cutter head 27 side and the child copy cutter 35 on the child cutter head 28 side. Since it is provided, it is not necessary to separate the support shaft 33 from the child copy cutter 35 or to pull back the child copy cutter 35, and a smooth start can be performed.

Thus, after the child shield machine 24 has started, the child cutter head 28 excavates the small diameter tunnel. In the case of performing overdrilling during this excavation, high pressure oil is supplied to the bottom side of the double-acting hydraulic cylinder 37 via the hydraulic pipe 39 to advance the support shaft 34. As a result, the child copy cutter 32 at the tip of the support shaft 34 excavates the ground around the child cutter head 28. Further, when the child copy cutter 32 is to be retracted after the over dug is completed, high pressure oil may be supplied to the rod side of the double-acting hydraulic cylinder 37 via the hydraulic pipe 38 to contract the piston rod 37a. . In this case, even if the double-acting hydraulic cylinder 37 is used, only two hydraulic pipes are required, so that the number of pipes can be halved compared to the conventional parent-child shield excavator.

FIG. 13 shows a modification of this embodiment. In this modification, a single-acting hydraulic cylinder 40 is used instead of the double-acting hydraulic cylinder 37, and a support shaft 41 on the child cutter head 28 side provided at the tip of a piston rod 40a of the single-acting hydraulic cylinder 40 is Similar to the support shaft 33 on the parent cutter head 27 side, the compression coil spring 43 inserted in the guide bush 42 is configured to be urged in the retracting direction (downward in FIG. 13). Other configurations are basically the same as those of the apparatus shown in FIG. Therefore, FIG.
The same parts as 2 are denoted by the same reference numerals and detailed description thereof will be omitted (the same applies to FIGS. 14 and 15 below).

In the copy cutter apparatus having the above-mentioned structure, when the high-pressure oil is supplied to the bottom side of the single-acting hydraulic cylinder 40 via the hydraulic pipe 39 when the overcutting is performed during the large-diameter tunnel excavation, the child cutter head 28 side is provided. Support shaft 41
The support shaft 33 on the side of the parent cutter head 27 is pressed and moved forward via, and the parent copy cutter 31 attached to the tip of this support shaft 33 excavates the ground around the parent cutter head 27. . In addition, when the parent copy cutter 31 is retracted after the over-digging is completed, if the bottom side of the single-acting hydraulic cylinder 40 is set to a low pressure, the child cutter head 2
The support shaft 41 on the 8 side is retracted by the compression coil spring 43, and the support shaft 33 on the parent cutter head 27 side is also retracted by the compression coil spring 36 to a required storage position.

On the other hand, when over-digging is performed during excavation of a small-diameter tunnel by the child shield machine 24 started from inside the parent shield machine 23, high pressure oil is supplied to the bottom side of the single-acting hydraulic cylinder 40 via the hydraulic pipe 39. The support shaft 41 is supplied to advance the support shaft 41, and the child copy cutter 32 at the tip of the support shaft 41 excavates the ground around the child cutter head 28. Also,
In the case where the child copy cutter 32 is retracted after the over-digging is completed, when the bottom side of the single-acting hydraulic cylinder 40 is set to a low pressure, the support shaft 41 on the child cutter head 28 side is compressed by the compression coil spring 43 to a desired storage position. Will be relocated. In the case of this modified example, since only one hydraulic pipe is required, the pipe can be further simplified.

FIG. 14 shows another modification of this embodiment. In this modification, a single-acting hydraulic cylinder 45 having a tension spring 44 therein is used instead of the double-acting hydraulic cylinder 37 in FIG. In this modified example, since the support shaft 34 on the child cutter head 28 side is retracted by the tension spring 44 incorporated in the single-acting cylinder 45, the same operation as the modified example shown in FIG. 13 can be performed. This is possible and only one hydraulic pipe needs to be used.

FIG. 15 shows still another modification of this embodiment. In this modified example, a single-acting hydraulic cylinder 47 having a tension spring 46 therein is provided on the child cutter head 28 side, and the single-acting hydraulic cylinder 47 is provided.
Directly onto the tip of the piston rod 47a of the child copy cutter 3
2 are provided. According to such a modification, the support shaft on the child cutter head 28 side can be omitted and only one hydraulic pipe is required, so that the structure can be further simplified.

(Third Embodiment) FIG. 16 is a side view of a copy cutter apparatus according to the third embodiment of the present invention.
This embodiment is applied to the parent-child shield machine as in the second embodiment.

In the parent-child shield excavator of this embodiment, the parent cutter head 27 is rotatably supported by the main body of the parent shield machine via bearings 48, whereby the parent cutter head 27 is advanced as the child shield machine 24 advances. Is designed so that it does not slip forward (to the face). Further, the copy cutter device is provided with a parent copy cutter 49 provided in the parent cutter head 27 and a child copy cutter 50 provided in the child cutter head 28, as in the second embodiment. The cutter 49 and the child copy cutter 50 are arranged so as to be coaxial when excavating as a parent and child.

A support shaft 51 is provided at the base end of the parent copy cutter 49, and this support shaft 51 is used for the parent cutter head 2.
It is supported by a guide bush 53 which is fixed to a base 52 in the inside 7. A stopper 54 is provided at the base end of the support shaft 51 to prevent the support shaft 51 from rotating about its axis. When the parent copy cutter 49 is retracted, the stopper 54 comes into contact with the convex portion 52a provided at the base end portion of the base 52 to prevent the parent copy cutter 49 from further retracting. . Even at the most retracted position of the parent copy cutter 49, the tip of a hook 61, which will be described later, is located outside the outer diameter of the child shield machine 24.

On the other hand, a support shaft 55 is provided at the base end portion of the child copy cutter 50, and this support shaft 55 is supported by a guide bush 57 fixed to a base 56 in the child cutter head 28. The base 5 is provided on the base end side of the support shaft 55.
A double-acting hydraulic cylinder 59 is swingably supported by a bracket 58 fixed to the inside of 6 via a trunnion (not shown).
The tip end of 9a is pivotally supported on the base end of the support shaft 55 via a ball joint (not shown). Further, one end of a hydraulic pipe (not shown) is connected to the bottom side and the rod side of the double-acting hydraulic cylinder 59. The support shaft 5
A stopper 60 similar to the stopper 54 for preventing the rotation of the support shaft 55 around the axis is provided at the base end of 5.

Stopper 54 on the parent cutter head 27 side
A hook 61 is provided on the lower surface of the child cutter cutter 28 so as to project toward the child cutter head 28, and a pin 62 is provided at the tip of the child copy cutter 50 so as to engage with the hook 61. As shown in FIG. 17, the hook 6
1 is composed of a pair of left and right, is attached so that the front side is open, and is arranged so as to fit in a notch 63 formed in the face plate of the parent cutter head 27.
On the other hand, the pins 62 are formed in a pair of left and right corresponding to the hooks 61 and are provided so as to project laterally from both side surfaces of the child copy cutter 50. Further, a convex portion 64 is formed on the base end side of the support shaft 51 on the parent copy cutter 49 side, and the convex portion 64 engages with the tip surface of the child copy cutter 50 when the hook 61 and the pin 62 are engaged with each other. It is supposed to meet. In the state where the parent copy cutter 49 and the child copy cutter 50 are connected, in other words, the hook 61 and the pin 62 are engaged,
The tip portion of the child copy cutter 50 is located outside the outer diameter of the child shield machine 24 and is located in the notch 63.

Next, the operation of the copy cutter device having the above-mentioned structure will be described with reference to FIGS. 16 and 18 to 25.

First, as shown in FIG. 16, when the parent shield machine 23 and the child shield machine 24 are integrated to excavate a large-diameter tunnel, the double-acting hydraulic cylinder is used. High pressure oil is supplied to the bottom side of 59 through a hydraulic pipe (not shown). Then, child copy cutter 5
The parent cutter head 27 through the convex portion 64 by the tip surface of 0.
Side support shaft 51 is pressed and moved forward,
The parent copy cutter 49 attached to the tip of the
As shown in FIG. 8, the parent copy cutter 49 is advanced to excavate the ground around the parent cutter head 27. In addition, after the over digging is completed, the parent copy cutter 49
When the piston rod 59a is retracted by supplying high-pressure oil to the rod side of the double-acting hydraulic cylinder 59 through a hydraulic pipe (not shown), the piston rod 59a contracts.
By pulling the hook 62 at the base end portion of the support shaft 51 on the parent cutter head 27 side by the pin 62 at the leading end portion of 0, the parent copy cutter 49 is retracted to the required storage position shown in FIG.

On the other hand, when the excavation of the large-diameter tunnel is completed and the small-diameter tunnel is continuously excavated from the large-diameter tunnel, when the child shield machine 24 is moved forward with respect to the parent shield machine 23, the hook 61 is released. Since the front side is open,
The hook 61 and the pin 6 can be moved only by moving the child shield machine 24 forward.
2 is disengaged and the parent copy cutter 49 and the child copy cutter 50 are disconnected (see FIG. 19). When the parent copy cutter 49 and the child copy cutter 50 are disconnected from each other in this way, the child copy cutter 50 is retracted into the child cutter head 28 (see FIG. 20), and the child shield machine 24 is further advanced (FIG. 21). reference). In this case, as described above, the parent copy cutter 49 is arranged such that the tip of the hook 61 is located outside the outer diameter of the child shield machine 24 even when the child copy machine 49 is in the most retracted state. The cutter 49 does not become an obstacle.

In the above description, the parent copy cutter 4 is used.
The child copy cutter 50 is retracted after the connection between the child copy cutter 9 and the child copy cutter 50 is cut off. However, since the notch 63 is provided in the front portion of the parent cutter head 27, it is shown in FIG. As described above, the child shield machine 24 may be moved forward without moving the child copy cutter 50 backward. In this way, even if a problem occurs in the child copy cutter 50 and the child copy cutter 50 cannot be shortened, it is possible to avoid the worst situation in which the child shield machine 24 cannot start.

After the child shield machine 24 has started, the child cutter head 28 excavates a small diameter tunnel (see FIG. 23). In the case of performing overdrilling during this excavation, high pressure oil is supplied to the bottom side of the double-acting hydraulic cylinder 59 via a hydraulic pipe (not shown) to advance the support shaft 55 (see FIG. 24). As a result, the child copy cutter 50 at the tip of the support shaft 55 enables over-digging of the ground around the child cutter head 28. In addition, when the child copy cutter 50 is retracted after the over-digging is completed, the double-acting hydraulic cylinder 5
Piston rod 59a by supplying high pressure oil to the rod side of 9
Should be contracted.

By the way, when the parent copy cutter 49 is at the most retracted position and the parent copy cutter 49 and the child copy cutter 50 are connected (the state shown in FIG. 16), the child copy cutter 50 is at the highest position. It is in a state of being extended by a certain amount (L1) from the contracted position. To make the parent copy cutter 49 appear and disappear from this state,
It is necessary to extend the child copy cutter 50 by the stroke amount (L2) required for the above. For this reason, in order to secure a necessary amount of extra digging during the excavation of the parent and child, the child copy cutter 50 must have a stroke of at least L1 + L2 or more. On the other hand, when the required stroke for securing the amount of excess excavation required during the excavation of the child shield machine 24 alone is L3, the child copy cutter 50 must have a stroke of L3 or more. is there. From these things, the child copy cutter 50
It is necessary to have a stroke of L1 + L2 or L3, whichever is larger.

FIG. 25 shows a state in which the slave copy cutter 50 is projected to the stroke end when the slave shield machine 24 is independently digging. This child copy cutter 50
Since it is set to have a stroke of L1 + L2 or L3, whichever is larger, as described above in consideration of the fact that it is also used when excavating as a parent and child, it protrudes to the protruding position shown in the figure. It is possible to
However, in actuality, it is not necessary to project to that projecting position during single excavation.

In the present embodiment, the parent cutter head 27
Although the face plate is provided with the notch 63, this notch is not always necessary. FIG. 26 shows the parent cutter head 2
7 shows an example in which the face plate 7 has no notch.
By eliminating the notch in this way, the connecting portion between the parent copy cutter 49 and the child copy cutter 50 can be protected, so that the copy cutters 49, 50 can be protected from damage or abrasion due to collision of earth and sand or rocks. . However, in the case of this modified example, the child copy cutter 50 is always retracted after the connection state between the parent copy cutter 49 and the child copy cutter 50 is released, and after this, the child shield machine 2 is restarted.
It is necessary to take the procedure of moving 4 forward.

In this embodiment, the child copy cutter 50 is used.
A description has been given of the case where the double-acting hydraulic cylinder 59 is used to move forward and backward.
A modification using a single-acting hydraulic cylinder 65 and a compression coil spring 66 as shown in FIG. 7 is also possible. That is, in this modification, the support shaft 55 on the child cutter head 28 side has the bearings 68 a, 6 in the guide bush 67.
8b is slidably supported in the radial direction of the child cutter head 28, and a spring seat 69 is projectingly provided in a spring chamber formed between the bearings 68a and 68b.
A compression coil spring 66 for urging the support shaft 55 in the backward direction is stretched between the shaft 9 and one of the bearings 68a.

According to this structure, by supplying high-pressure oil to the bottom side of the single-acting hydraulic cylinder 65, the support shaft 55 and the child copy cutter 50 are moved forward, and the bottom side of the single-acting hydraulic cylinder 65 is made low pressure. By switching to oil, the support shaft 55 and the child copy cutter 50 are retracted by the spring force of the compression coil spring 66. In this modification, since only one hydraulic pipe is required, the structure can be simplified.

In this embodiment, the child shield machine 24 is moved forward to release the connection between the parent copy cutter 49 and the child copy cutter 50, but this connection release is performed by the child cutter. A modified example in which the head 28 is rotated is also possible. In this modification, as shown in FIG.
As shown in FIG. 29, a pair of hooks 70 and a pair of pins 71 are provided on the front surface and the rear surface of the child copy cutter 50, respectively, and the child cutter head 28 relative to the parent cutter head 27. The connection between the parent copy cutter 49 and the child copy cutter 50 is released by rotating the parent copy cutter 49 and the child copy cutter 50.

In the copy cutter apparatus having such a configuration, the parent copy cutter 49 and the child copy cutter 50
In order to release the connection with the parent cutter head 27, first, the parent cutter head 27 is fixed so as not to rotate, and then the child cutter head 28 is rotated and stopped by the cutter head driving device until the connection is released. Here, in order to fix the parent cutter head 27, the child copy cutter 50 is moved forward while the rotation of the cutter head is stopped, the parent copy cutter 49 is inserted into the ground, and the parent cutter head 27 is grounded. The method of fixing is easy. Note that in the example shown in FIG. 28, the face plate of the parent cutter head 27 is not provided with the notch, but in the case of this modification as well, the notch as described above can be provided.

In the present embodiment and each of the modified examples described above,
Although the hooks 61 and 70 are provided on the parent copy cutter 49 side and the pins 62 and 71 are provided on the child copy cutter 50 side, the pin is provided on the parent copy cutter 49 side and the hook is provided on the child copy cutter 50 side. It is also possible to provide.

In the present embodiment and each of the modified examples described above,
Although the one in which the parent copy cutter 49 and the child copy cutter 50 are connected by the hook and the pin has been described, a modification in which a disconnectable wire is used as the connecting means is also possible. In this modified example, as shown in FIG. 30A, a protrusion 72 is provided on the base end side of a stopper 54 provided on the support shaft 51 on the parent cutter head 27 side, and a front face of the protrusion 72 and Wires 75 are stretched between mounting seats 73 provided on the rear surface and mounting seats 74 provided on the front surface and the rear surface of the child copy cutter 50, respectively. Here, as the wire 75, it is preferable to use a material having high tensile strength and easily cuttable, and for example, carbon fiber or glass fiber is most suitable.

In the copy cutter apparatus of this modified example, when the child copy cutter 50 is moved forward, the parent copy cutter 49 is pushed forward by the tip of the child copy cutter 50, and when the child copy cutter 50 is moved backward, the parent copy cutter 49 is moved. Is pulled by the wire 75 and retracts. And the child shield machine 24
30B, the wire 75 is pulled while the child copy cutter 50, the protrusion 72, the parent cutter head 27, and the child cutter head 28 are pulled as shown in FIG.
Each edge portion 76 (see FIG. 30C) is pressed and cut. It should be noted that cutting performance is improved by sharpening these edge portions 76 in advance.

According to this modification, when the parent copy cutter 49 and the child copy cutter 50 are connected and the parent copy cutter 49 is retracted, the rear end of the parent copy cutter 49 is placed outside the child cutter head 28. It is possible to position the tip of the child copy cutter 50 inside the outer diameter of the child cutter head 28 while being positioned outside the diameter.
Therefore, the parent copy cutter 49 and the child copy cutter 50 can be separated from each other only by moving the child shield cutter 24 forward after retracting the child copy cutter 50, and no trouble such as catching occurs at the time of this separation. Further, it is not necessary to provide a notch on the face plate of the parent cutter head 27.

As described above, it is obvious that the present invention can be modified in various ways. Such modifications are within the spirit and scope of the invention, and all such variations and modifications apparent to those skilled in the art are intended to be within the scope of the following claims.

[Brief description of drawings]

FIG. 1 is a front view of a shield machine according to a first embodiment of the present invention.

FIG. 2 is a vertical sectional view of the shield machine according to the first embodiment.

FIG. 3 is an enlarged front view of the copy cutter apparatus according to the first embodiment.

FIG. 4 is a sectional view of a copy cutter device according to a first embodiment.

5 is an enlarged view of part A of FIG.

FIG. 6 is an operation explanatory view of the copy cutter apparatus according to the first embodiment.

FIG. 7 is an operation explanatory view of the copy cutter apparatus according to the first embodiment.

FIG. 8 is an explanatory diagram of a copy cutter device according to a modification of the first embodiment.

FIG. 9 is an explanatory diagram of a copy cutter device according to another modification of the first embodiment.

FIG. 10 is a vertical cross-sectional view of a shield machine according to a second embodiment of the present invention.

FIG. 11 is an enlarged cross-sectional view of a copy cutter device according to a second embodiment.

FIG. 12 is an operation explanatory view of the copy cutter apparatus according to the second embodiment.

FIG. 13 is an explanatory diagram of a copy cutter device according to a modification of the second embodiment.

FIG. 14 is an explanatory diagram of a copy cutter device according to another modification of the second embodiment.

FIG. 15 is an explanatory diagram of a copy cutter device according to still another modification of the second embodiment.

FIG. 16 is a side view of a copy cutter device according to a third embodiment of the present invention.

FIG. 17 is a front view (a), a partially enlarged view (b) of (a) and a side view (c) of an engaging portion of a copy cutter device according to a third embodiment.

FIG. 18 is an operation explanatory view of the copy cutter apparatus according to the third embodiment.

FIG. 19 is an operation explanatory view of the copy cutter apparatus according to the third embodiment.

FIG. 20 is an operation explanatory view of the copy cutter apparatus according to the third embodiment.

FIG. 21 is an operation explanatory view of the copy cutter apparatus according to the third embodiment.

FIG. 22 is an operation explanatory view of the copy cutter apparatus according to the third embodiment.

FIG. 23 is an operation explanatory view of the copy cutter apparatus according to the third embodiment.

FIG. 24 is an operation explanatory view of the copy cutter apparatus according to the third embodiment.

FIG. 25 is an operation explanatory view of the copy cutter apparatus according to the third embodiment.

FIG. 26 is an explanatory diagram of a copy cutter device according to a first modification of the third embodiment.

FIG. 27 is an explanatory diagram of a copy cutter device according to a second modification of the third embodiment.

FIG. 28 is an explanatory diagram of a copy cutter apparatus according to a third modification of the third embodiment.

FIG. 29 is a front view of the copy cutter device of FIG. 28.

FIG. 30 is an explanatory diagram (a), an operation explanatory diagram (b) and an edge explanatory diagram (c) of a copy cutter device according to a fourth modification of the third embodiment. .

FIG. 31 is an explanatory diagram showing a conventional copy cutter device.

FIG. 32 is a vertical cross-sectional view of a parent-child shield machine equipped with a conventional copy cutter device.

FIG. 33 is an operation explanatory view of a parent-child shield excavator including a conventional copy cutter device.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 shield main body 4 cutter head 4a outer peripheral surface 10 copy cutter device 15, 36, 43, 66 compression coil spring 15 ', 44, 46 tension spring 16 copy cutter 20, 20', 40, 45, 47, 65 single acting hydraulic cylinder 23 Parent Shield Machine 24 Child Shield Machine 27 Parent Cutter Head 28 Child Cutter Head 31,49 Parent Copy Cutter 32,50 Child Copy Cutter 37,59 Double-acting Hydraulic Cylinder 48 Bearing 61,70 Hook 62,71 Pin 63 Notch 75 Wire 76 Edge

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Sachi Mochizuki 1-1-103, Chiwaka-cho, Kanagawa-ku, Yokohama, Kanagawa Prefecture (72) Izumi Nishizawa 3-1-1, Ueno, Hirakata-shi, Osaka Komatsu Ltd. Inside the Osaka Plant (72) Inventor Yasuo Ichimura 3-1-1 Ueno, Hirakata, Osaka Prefecture Komatsu Ltd. Osaka Plant

Claims (13)

[Claims] 1. A shield machine having a cutter head at a front portion of a shield body, wherein a copy cutter is provided on an outer peripheral surface of the cutter head, the copy cutter protruding by an operation of a driving means and retracted by a spring force. Characteristic shield machine. 2. The shield machine according to claim 1, wherein the drive means is a single-acting hydraulic cylinder. 3. A shield machine comprising a large-diameter parent shield machine having an annular parent cutter head and a small-diameter child shield machine having a disk-shaped child cutter head, wherein the parent cutter head is provided. A parent copy cutter and a child copy cutter provided on the child cutter head are arranged in series in the radial direction of the parent cutter head and the child cutter head, and the parent copy cutter is provided on the child cutter head via the child copy cutter. Is provided with a driving means for projecting the parent cutter head from the outer peripheral surface of the parent cutter head, and the parent cutter head is provided with a spring for retracting the parent copy cutter from the outer peripheral surface of the parent cutter head. . 4. A shield machine comprising a large-diameter parent shield machine having an annular parent cutter head and a small-diameter child shield machine having a disc-shaped child cutter head, wherein the parent cutter head is provided. The base end portion of the parent copy cutter and the tip end portion of the child copy cutter provided in the child cutter head are provided so as to be connectable or disconnectable via connecting means, and the child cutter head is provided with the child copy cutter via the child copy cutter. A shield machine having a drive means for projecting the master copy cutter from the outer peripheral surface of the master cutter head. 5. The shield machine according to claim 3, wherein a spring for retracting the slave copy cutter from the protruding position is provided, and the drive means is a single-acting hydraulic cylinder. 6. The shield machine according to claim 4, wherein the drive means is a double-acting hydraulic cylinder. 7. The connecting means releases the connected state by advancing the child shield machine from the connected state of the base end portion of the parent copy cutter and the tip end portion of the child copy cutter. 5. A pin provided on either one of the parent copy cutter and the child copy cutter and a hook provided on the other of the parent copy cutter and the child copy cutter.
The shield machine described in. 8. The connecting means releases the connected state by rotating the child shield machine from the connected state of the base end portion of the parent copy cutter and the tip end portion of the child copy cutter. 5. A pin provided on either one of the parent copy cutter or the child copy cutter and a hook provided on the other of the parent copy cutter and the child copy cutter.
The shield machine described in. 9. The connecting means is a wire that connects a base end portion of the parent copy cutter and a tip end portion of the child copy cutter, and the base end portion of the parent copy cutter and the child copy cutter are connected by the wire. The shield machine according to claim 4, wherein the wire is pressed against a required edge portion and cut by advancing the child shield machine from a state of being connected to the tip portion of the shield shield machine. 10. The shield machine according to claim 4, wherein the parent cutter head is rotatably supported by the parent shield machine main body. 11. The base end portion of the parent copy cutter is located outside the outer peripheral surface of the child cutter head even when the parent copy cutter is in the most retracted state. A shield machine as described in any of the above. 12. The tip of the child copy cutter is located outside the outer peripheral surface of the child cutter head when the parent copy cutter and the child copy cutter are connected and the parent copy cutter is in the most retracted state. The child copy cutter is configured to project by a projecting amount, and the child copy cutter has a stroke amount obtained by adding the predetermined projecting amount to the stroke amount required for the parent copy cutter, and a stroke necessary for performing overditch by the child copy cutter. 12. The shield machine according to claim 11, wherein the shield machine has a stroke that is greater than or equal to a quantity, whichever is larger. 13. A face plate of the parent cutter head, which corresponds to a tip portion of the child copy cutter protruding outward from an outer peripheral surface of the child cutter head in a state where the parent copy cutter and the child copy cutter are connected to each other, The shield machine according to claim 12, wherein the shield machine is cut out.