JP2728373B2 - Tunnel invert cutting equipment - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a tunnel invert cutting apparatus capable of cutting a tunnel invert quickly, efficiently and accurately.

[0002]

2. Description of the Related Art In a hydroelectric power plant, for example, the flow of a river is blocked by a water dam, water is guided from a water intake to a pressure regulating tank of the power plant through a headrace, and the water tank is connected to the power plant by a hydraulic pipe. I try to send water. In general, a concrete dark or open channel is used for the water channel, and a foreign matter filter is provided at an intake port of the channel. Gravel may penetrate through the filter, and the gravel may enter the water channel. In particular, the bottom surface is eroded and disturbs the water flow, causing an increase in fluid friction and a decrease in flow rate.In addition, the strength of the culvert-shaped channel is reduced with respect to earth pressure and overburden load. Become.

Conventionally, for repair of concrete laid on the bottom surface of a tunnel type headrace, ie, invert, the invert has been cut or broken by a giant breaker or a chipping hammer, and the relevant portion has been restored to concrete.

However, according to the conventional repair method, for example, in the case of a giant breaker, the entire invert is destroyed, which is not only wasteful in terms of the construction method, but also requires a large amount of construction work, resulting in a longer construction period and an increase in construction costs. In the case of using a chipping hammer, there is a problem in that the efficiency of the operation is inferior due to the shallow cut thickness per operation due to the structure of the machine, and the construction period is prolonged.

[0005] Such repair of the invert is not impossible even with a conventional tunnel cutting device. For example, a tunnel inner wall surface cutting device (Japanese Patent Application Laid-Open No. Hei 6-81586) includes a turning arm on which a cutter drum is mounted, which is turned in the circumferential direction of the tunnel to cut the arch and side walls of the tunnel and the invert. ing.

However, in this conventional cutting apparatus, the entire inner wall surface of the tunnel is cut in the circumferential direction so that the arch and side walls of the tunnel and the invert can be cut. Since it is cut in an arc shape, it cuts to the side wall part that does not require repair, the part can not be cut reliably, and since the range that can be cut in one set is narrow, the construction speed is slow, etc. There was a problem.

[0007]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and it has been made possible to cut a tunnel invert quickly, efficiently and accurately, and to make a corner of the invert square. An object is to provide a cutting device.

[0008]

SUMMARY OF THE INVENTION Therefore, an invert cutting device for a tunnel according to the present invention comprises a front and rear portion provided with running means.
The main body is separated from the main body.
A guide rail along the rail, and move the cutter along the rail.
Moveable, cutter drum can be rotated on the cutter
The cutter in the circumferential direction below the tunnel.
In the tunnel inverting cutting device that can be turned, the inverting cutting device is divided in parallel with the center line in the front-rear direction.
Can be split and can be used to cut inverts of various widths
It is to function. The present invention is an invert cutting device front and rear
And can be divided in parallel to the center line of the
Connect with a spacer in between to cut the wide invert
It corresponds to cutting . The present invention, Rateraruga the cutter
A cross guide that supports the guide rail so that it can move in the direction perpendicular to the guide rail.
Draft, making the cross guide rail indivisible
Configured and selectively use cross guide rails of various lengths
To be able to cut inverts of various widths
In addition, the cutter can be moved smoothly .

[0009]

According to the first aspect of the present invention, a front and rear part having a traveling means is provided.
The main body is separated from the main body.
A guide rail along the rail, and move the cutter along the rail.
Moveable, cutter drum can be rotated on the cutter
The cutter in the circumferential direction below the tunnel.
In the tunnel inverting cutting device that can be turned, the inverting cutting device is divided in parallel with the center line in the front-rear direction.
Can be split and can be used to cut inverts of various widths
Make it work. The invention according to claim 2 is characterized in that the
It is configured so that it can be divided parallel to the center line in the backward direction, and each joint
A wide invert is connected by inserting a spacer between the parts
To cutting Ru made to correspond. According to the third aspect of the present invention, the cutter
A support that can move in the direction perpendicular to the
Provide a loss guide rail and divide the cross guide rail
Impossible configuration, select cross guide rails of various lengths
Used for cutting inverts of various widths
At the same time, the cutter moves smoothly .

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. In FIGS. 1 to 5, reference numeral 1 denotes a tunnel which is a headrace of a canal type power generation, which includes an arch 1a, a side wall 1b, and an invert 1c. The cutting device 2 is movably carried therein. The cutting device 2 includes front and rear body parts 3 and 4
A pair of right and left traveling crawlers 5 and 6 as traveling means are provided on the main bodies 3 and 4 via frame frames 3a and 4a. The crawlers 5 and 6 are supported so as to be swingable in a direction perpendicular to the running direction, can be grounded according to the curvature of the running surface, and have a turntable 7 on the inner ends of the front and rear main bodies 3 and 4. , 8 are attached to be rotatable in the horizontal direction, and front and rear support frames 9, 10 are erected on the tables 7, 8.

In the figure, reference numerals 11 and 12 denote turntables 7 and 8, respectively.
The adjusting cylinders 13 and 14 which can adjust the rotation angle of the front and rear support frames 9 and 10 are a pair of left and right side jacks attached to the front and rear end portions of the front and rear support frames 9 and 10, and can be expanded and contracted sideways.

A pair of left and right lateral guide rails 15 are provided between the front and rear support frames 9 and 10.
The cutter 16 is provided movably along. That is, the cutter 16 includes a pair of left and right mounts 17, the mount 17 has a plurality of traveling wheels 18 that can travel along the guide grooves 15 a, and these mounts 17 are connected by a cross guide rail 19. I have. In this case, as a means for moving the cutter 16, for example, a method is employed in which the gantry 17 is self-propelled via a traveling motor or the gantry 17 is moved via a movable jack.

The cross guide rail 19 is formed in a rectangular cross section, and a cutter body 20 having a substantially inverted U-shaped cross section is slidably fitted to the rail 19, and a hydraulic motor for laterally moving the cutter is provided below the body 20. And the like, and a drive gear 22 of the actuator 21
9 is engaged with a rack 23 protruding from the lower end surface. An actuator 24 such as a hydraulic motor for turning the cutter arm is provided above the cutter body 20, and a drive gear 25 of the actuator 24 meshes with a ring gear 26 for turning the cutter arm.

The cutter arm turning ring gear 26 includes:
An arm holder 27 is fixed to the ring gear 26 so as to be rotatable at a rear portion of the cutter body 20.
The arm holder 27 is formed in a hollow quadrangular prism shape, and a cutter arm 28 is fitted inside the holder 27 so as to be slidable in the vertical direction, and is rotatable in the lower part of the tunnel 1, that is, in the circumferential direction of the invert 1c. Have been.

A drive motor 29 and a speed reducer 30 are provided in the upper portion of the cutter arm 28, and transmit the power to a pair of left and right cutter drums 31. Cutter drum 3
Numeral 1 is rotatably supported on both sides of the lower end of the cutter arm 28, which has a truncated conical shape or a conical shape as shown in the figure, and enables cutting in accordance with the curvature of the invert 1c. In the drawing, reference numeral 32 denotes concrete laid on the invert 1c.

At the rear upper end of the arm holder 27, a cutter arm raising / lowering jack 33 is mounted upward, and the upper end of a piston rod 34 is rotatably connected to a bracket 35 projecting from the upper end of the cutter arm 28. Thus, the cutting amount h and the curvature of the cutter drum 31 with respect to the concrete floor 32 can be set.

The operation of the cutter 16 is controlled by a computer which will be described later, and enables automatic cutting. That is, the computer is installed in an electric control device which will be described later. The computer includes a turning angle of the cutter arm 28 corresponding to the cutting position of the invert 1c, a position of the cutter body 20 on the cross guide rail 19,
Correlation information with the set length of the arm 28 is stored, and based on the information, the sectional shape of the tunnel 1 and the invert 1c to be actually cut, the cutting start position, the cutting amount h and the cutting speed, the tunnel 1 Under the conditions of inputting the cutting distance along the axial direction of the actuator, the rotation angles and the number of rotations of the actuators 21 and 24, the amount of expansion and contraction of the cutter arm elevating jack 33, and the amount of operation of the traveling motor or the moving jack are calculated. Calculation results can be output to them as control signals.

In the drawing, reference numeral 36 denotes an invert 1 which is a portion to be cut.
The cut groove 37 formed in the concrete 32 of c is an outrigger attached to the front and rear lower ends of the lateral guide rails 15 and is capable of extending and contracting in the vertical direction. 38 is a driver's seat provided on the front body 3, 39 is an electric control device equipped with a computer, 40 is a hydraulic device provided on the rear body 4, 41 and 42 are on inner end surfaces of the front and rear support frames 9 and 10. A fixed, substantially inverted U-shaped connecting frame, and a lateral guide rail 1
5 are connected at the front and rear ends.

On the other hand, the front and rear main bodies 3, 4 and the frame 3a, 4
a, and front and rear support frames 9, 10 and connecting frames 41, 42
Can be divided into two parts with respect to the center line L in the front-rear direction of the cutting device 2, and their joint end faces are connected via screw fastening means such as fastening bolts, and a single spacer 43 is provided between them. The distance between the pair of left and right front and rear main bodies 3, 4 and the like can be adjusted by interposing -46.

In this case, the cross guide rail 19 is configured so as not to be divided into left and right, and the lateral guide rail 1
With respect to the change in the distance of 5, 15, various lengths corresponding to those dimensions are prepared, and their cross-sectional shapes are formed in the same shape, so that the sliding of the cutter body 20 is facilitated and shared. In addition, the arm holder 27 fixed to the body 20 and the cutter arm 28 are shared.

The spacers 43 to 46 are formed to have the same thickness.
Their shapes are the front and rear main bodies 3 and 4 to be inserted, the frame 3
a, 4a, the front and rear support frames 9, 10, and the connection frames 41, 42 are formed in the same cross-sectional shapes as those of the first embodiment, and are provided with a plurality of bolt insertion holes (not shown). In addition, the front and rear body parts 3, 4 and the frames 3a, 4a, and the front and rear support frames 9, 1
0 and a single spacer 43-4 between the connection frames 41 and 42.
6 instead of interposing a plurality of spacers 43-4 between each.
6 may be interposed, so that the spacer 4
3 to 46 can be reduced in size and weight, and the attachment / detachment work becomes easy.

Since the tunnel invert cutting device thus configured is a cutting device dedicated to the invert portion as described later, the cutter arm 28 has a smaller size than a conventional cutting device that also serves to cut the arch portion 1a and the side wall 1b. , And the capacity of the actuators 21 and 24 can be reduced, so that this type of cutting device can be reduced in size and the manufacturing cost can be reduced.

Next, using the above cutting device, the tunnel 1
When cutting the damaged invert 1c, the crawlers 5 and 6 are driven to carry the cutting device 2 into the tunnel 1, and
When this moves to a predetermined position, the device 2 is stopped. Thereafter, the outriggers 37 are extended and the cutting device 2 is jacked up on the invert 1c, and the side jacks 14 are extended and the cutting device 2 is held in the tunnel 1.

In this case, when the tunnel 1 is curved in a plane as shown in FIG. 2, the cutting device 2 is stopped, one or both of the adjusting cylinders 11 and 12 are operated, and the amount of expansion and contraction is appropriately adjusted. Then, the turntables 7, 8 associated with the cylinders 11, 12 are appropriately rotated in a predetermined direction.

In this way, the front and rear support frames 9, 10
Move together with the turntables 7, 8, and the lateral guide rails 15, 15 move together with the turntables 7, 8.
15 is bent with the front and rear main bodies 3 and 4 in a plane, and the tunnel 1
The cutting device 2 can be carried in and moved according to the various curves.

Thereafter, a computer provided in the electric control device 39 stores the sectional shape of the tunnel 1 to be cut and the invert 1c, the cutting start position, and in the embodiment, the invert 1c.
, And information such as the cutting amount h, the cutting speed, and the cutting distance in the axial direction of the tunnel 1.

The computer calculates the rotation angle of the cutter arm 28 corresponding to the cutting position of the invert 1 c stored in advance, the position of the cutter body 20 on the cross guide rail 19, and the set information of the arm 28. The actuators 21 and 21 are provided on condition of the input information.
The rotation angle and number of rotations of 4, the amount of expansion and contraction of the cutter arm elevating jack 33, and the amount of operation of the traveling motor or the moving jack are calculated, and the calculation results are output to them as control signals.

When the control signal is input to the actuator 21, the actuator 21 is driven,
The drive gear 22 rotates, and the gear 22 moves along the rack 23 meshed with the drive gear 22, and the actuator 21 moves together with the gear. For this reason, the cutter body 20 integrated with the actuator 21 moves along the cross guide rail 19 and stops when the cutter body 20 moves by an amount corresponding to the control signal.

When the control signal is input to the actuator 24, the actuator 24 is driven, the drive gear 25 is rotated, and the cutter arm turning ring gear 26 meshing with the gear 25 is rotated. , An arm holder 27 integral with the gear 26 moves together with the gear 26.

For this reason, the cutter arm 28 fitted to the arm holder 27 pivots in the circumferential direction of the tunnel 1,
It stops when it moves by the amount corresponding to the control signal, that is, when it turns to a position corresponding to the cutting start position.
This situation is as shown in FIG. 3, in which the tip of one cutter drum 31 is positioned at the corner 1d of the inverting section 1c.

Further, when a control signal is input to the cutter arm lifting / lowering jack 33, the jack 33 expands and contracts, and the cutter arm 2 is moved via its piston rod 34.
8 is moved up and down by the control signal, and stops when the cutting amount h of the cutter drum 31 at the lower end of the arm 28 is set. In this case, a drive signal is input to the drive motor 29 and the speed reducer 30 before and after the input of the signal to the lifting jack 33, and these are driven to drive the power to the cutter drum 3.
1, 31 and the drums 31, 31 are synchronously rotated to enable cutting.

When a control signal is input to the traveling motor or the moving jack (not shown) under such a situation, the control signal is driven to move the pair of pedestals 17 into the guide grooves 15.
The cutter 16 moves along the line a and starts cutting. That is, the cutter 16 positions one of the cutter drums 31 at the corner 1d of the invert 1c, which is the cutting start position, and maintains the set cutting amount h and the turning angle of the cutter arm 28 in the axial direction of the tunnel 1. At the set speed, when this travels a predetermined distance, in this embodiment, the traveling wheels 18 are moved to the front and rear support frames 41, 42.
Moves up to the maximum moving distance up to the position immediately before contact with the stop, and stops.

The cutting conditions in this case are as follows: starting from the corner 1d of the invert 1c,
1 are formed in the circumferential direction of the tunnel 1 so as to be spaced apart from each other, and these grooves 36, 36 are formed at a predetermined distance in the axial direction of the tunnel 1, and are located at the corners 1d. The inner surface of the cutting groove 36 is formed in a direction normal to the concave curved surface of the invert 1c.

When the movement of the cutter 16 is stopped in this way, the cutting of the relevant portion is completed, and the signal is input to the computer. Thereafter, the computer sends a control signal to the cutter arm lifting / lowering jack 33 to extend the jack 33, pull up the cutter arm 28, and pull out the cutter drums 31, 31 from the cutting grooves 36, 36.

Next, the computer operates the actuator 2
1 and 24, among which actuator 2
1 is driven to rotate the drive gear 22, and the gear 22 is moved along the rack 23 meshing with the drive gear 22, so that the actuator 21 and the cutter body 20 are connected to the cross guide rail 1
3 is moved to the upper left in FIG. 3, and these are moved by an equivalent of a control signal, that is, by one pitch, and stopped.

Further, the actuator 24 is driven to rotate the drive gear 25, and the cutter arm turning ring gear 26 meshing with the gear 25 is rotated to move the arm holder 27 integral with the gear 26. , Cutter arm 28
Is turned clockwise in FIG. 3 in the circumferential direction of the tunnel 1, and is turned by an amount corresponding to the control signal, and is stopped at the next cutting start position.

In the embodiment, the cutter drums 31, 31 are moved toward the center of the
After moving by an amount corresponding to the individual width, one cutter drum 31 is positioned immediately above the uncut portion between the cutting grooves 36, 36, and the other cutter drum 31 is positioned immediately above the adjacent position of the cutting groove 36 on the center side.

Thereafter, the cutter arm elevating jack 33
The cutter arm 28 is lowered by the control signal via the piston rod 34, the cutting amount of the cutter drum 31 is set to the same amount h as described above, and the operation is stopped. In this case, the drive motor 29 and the speed reducer 30 continue to drive, and the cutter drum 31 can be cut.

Then, under such circumstances, the computer drives the traveling motor or the moving jack (not shown) in the reverse direction, moves the cutter 16 backward, and starts cutting.
That is, the cutter 16 cuts an uncut portion between the cutting grooves 36, 36 with one cutter drum 31, and cuts a position adjacent to the cutting groove 36 on the center side with the other cutter drum 31, and moves to the original position. Stop when done.

The cutting conditions in this case are as follows:
The uncut portion between the two is cut, and the position adjacent to the center cutting groove 36 is cut, so that the circumferential direction of the tunnel 1 is cut by the width of four cutter drums 31 and the cutting groove 3 is cut.
6 are formed in the axial direction of the tunnel 1.

When the cutter 16 returns to its original position and stops moving in this way, the computer operates the cutter arm elevating jack 33 and the actuator 2 in the same manner as described above.
By controlling the operations of the cutters 1 and 24, the cutter drums 31 and 31 are positioned at the next cutting position, and the cutter 16 is moved forward to cut the invert 1c. Thereafter, these operations are repeated to cut the entire surface of the invert 1c.

As described above, this cutting device is an invert 1
Since it is a dedicated machine that cuts only c, the position setting and position adjustment of each part by the computer is quicker and easier than a device that cuts the arch portion 1a and the side wall 1b of the tunnel 1 or the entire peripheral surface. In addition to being suitable for automatic cutting, the cutter 16 is moved in a wide range in the axial direction of the tunnel 1 for cutting.
As compared with the case of cutting in the circumferential direction, the cutting range per process can be set wider, and the cutting speed can be increased and the construction period can be shortened.

Also, since the truncated cone-shaped cutter drum 31 is used, it is more easily adapted to the cutting of the invert 1c having a generally concave curved surface than the cylinder-shaped cutter drum, and is easily adapted to the cutting of various curvatures. Can be Moreover, since the cutting amount of the cutter drum 31 can be appropriately set and the cutting amount can be adjusted, the construction does not require a large amount of work as compared with a conventional method in which all the cut portions are broken down like a giant breaker. In addition, compared with a conventional method in which a large cutting thickness cannot be obtained as in the case of a conventional chipping hammer, the cutting efficiency can be improved and the construction period can be shortened.

After the entire surface of the invert 1c has been cut in this manner, the concrete 32 is driven into the cut portion to complete a series of repair work. In this case, the cutting grooves 3 located at the corners 1d, 1d of the invert 1c as described above.
6 is accurately formed in the normal direction to the surface of the invert portion, so that the cylindrical cutter drum is
As compared with the conventional cutting method for cutting in the circumferential direction, no post-operation is required for forming the corners 1d, 1d into a square which is effective for tunnel mechanics.

After the concrete 32 is solidified,
Stress that acts on the invert 1c in the circumferential direction of the tunnel 1, that is, axial stress, is sufficiently resistant to form a strong invert 1c that does not cause slip.

The tunnel 1 has a large cross section and the invert 1
When the width of c is wide, for example, before the cutting device 2 is carried in, the driver's seat 38, the electric control device 39, and the hydraulic device 40 are removed, and the upper surfaces of the front and rear body parts 3, 4 are opened. Loosen the bolts, and a pair of left and right
4 and the frames 3a and 4a, and the front and rear support frames 9 and 10 and the connection frames 41 and 42, and the invert 1c is interposed therebetween.
After inserting spacers 43 to 46 of a required length corresponding to the width of
A driver's seat 38, an electric control device 39, and a hydraulic device 40 on the upper surface of the vehicle

In this case, a cross guide rail 19 having a length corresponding to the space between the lateral guide rails 15 after the dimension change is prepared, and the mounts 17 are mounted on both ends thereof.

Then, the gantry 17, 17 is inserted into the guide groove 1
5a and 15a, and the cutter base 2 is attached to a cross guide rail 19 connected between the mounts 17 and 17.
The cutter 20 such as a cutter holder 27, a cutter arm 28, and a cutter drum 31 is mounted on the base 20.
Assemble the main part of. The components of the cutter 16 are shared except for the cross guide rail 19.

The cutting device 2 thus assembled is as shown in FIG. 5, and a pair of right and left front and rear body members 3, 4 and frame frames 3a, 4a,
And the front and rear support frames 9 and 10 and the connection frames 41 and 42
The width is increased by the interposition of the spacers 43 to 46, and the pair of right and left crawlers 5 and 6, the side jack 14, and the outrigger 37 are provided.
The interval between the two becomes wider. Along with this, a long cross guide rail 19 is used, and the moving range of the cutter 16 along the rail 19 is widened, so that the wide invert 1c can be cut.

[0050]

As described above, the tunnel invert cutting device of the present invention has the lateral guide rails on the front and rear main bodies.
Provide front and rear support frames that support one end, and
It is possible to rotate the invert cutting device back and forth
Because it can be divided parallel to the center line of the direction,
It can correspond to the cutting of the width invert . In addition, the present invention provides an invert cutting device that is parallel to the center line in the front-rear direction.
And a spacer between each joint.
Since it is inserted and connected, it can cope with the cutting of a wide invert . The invention further Rateraruga the cutter
A cross guide that supports the guide rail so that it can move in the direction perpendicular to the guide rail.
Draft, making the cross guide rail indivisible
Configured and selectively use cross guide rails of various lengths
That it can handle the cutting of inverts of various widths
In addition, there is an effect that the cutter can move smoothly .

[Brief description of the drawings]

FIG. 1 is a front view showing an embodiment of the present invention, and shows a state where a vehicle is carried into a tunnel.

FIG. 2 is a plan view of FIG.

FIG. 3 is a cross-sectional view showing a cutting start state of an invert according to the present invention.

FIG. 4 is a cross-sectional view showing an intermediate state of cutting an invert according to the present invention.

FIG. 5 is a cross-sectional view in which the present invention is applied to the cutting of a wide invert.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Tunnel 1c Invert 2 Cutting device 3 Front main body 4 Rear main body 5, 6 Traveling means (crawler) 9 Front support frame 10 Rear support frame 15 Lateral guide rail 16 Cutter 19 Cross guide rail 28 Cutter arm 31 Cutter drum 43-46 Spacer L Center line

 ──────────────────────────────────────────────────続 き Continuing on the front page (72) Inventor Toshio Takagi 852 Saya, Itonuki-cho, Motosu-gun, Gifu Prefecture (72) Inventor Hiroyuki Hishida 127-1, Tsukina-cho, Takehana-machi, Hashima-shi, Gifu (72) Inventor Yoshiharu Aoki 541-3 Manai, Kazo City, Saitama Prefecture (72) Inventor Jun Sugiyama 30-1 Kasamatsu-cho, Hashima-gun, Gifu Prefecture (72) Inventor Osamu Takahashi 1282-2-2 Nakagamicho, Akishima-shi, Tokyo 203 (72) Inventor Yasushi Maki 1-52-8 Sakuradai, Yokkaichi City, Mie Prefecture (72) Kinji Sawada 2-62 Tobimotocho, Nakagawa-ku, Nagoya City, Aichi Prefecture (72) Inventor ▲ Akira Yoshi ▼ 7-14-10 Chuodai, Kasugai-shi, Aichi (72) Inventor Akira Inoue 10-12-2 Fujiyamadai, Kasugai-shi, Aichi (56) References JP-A-4-108999 (JP, A) Akira Tokubo 42-12043 (JP, B1) JP-B 60-12490 (JP, B2)

Claims (3)

(57) [Claims] 1. A front and rear body provided with a traveling means is separated from each other.
Arrange the lateral guide rail between these front and rear body
And the cutter can be moved along the rail.
The cutter drum is provided rotatably on the cutter,
In invert cutting device of the tunnel it was <br/> provided pivotably in the circumferential direction of the tunnel lower the serial cutter, invert
An invert cutting device for a tunnel, wherein the cutting device is configured to be able to be divided in parallel with the center line in the front-rear direction . 2. An inverting cutting device is provided with a center line in the front-rear direction.
And can be divided in parallel with each other, with a space between each joint.
2. The tunnel invert cutting device according to claim 1, wherein the tunnel invert cutting device is connected to the tunnel by an intermediary . 3. The cutter is orthogonal to the lateral guide rail.
A cross guide rail that supports the direction of movement is provided,
The cross guide rail is configured to be indivisible and has various lengths
3. The tunnel invert cutting device according to claim 2 , wherein said cross guide rail is selectively used .