JP2003206700A - Ventilating equipment in tunnel - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To dispense with a local blower, simplify equipment and further realize good ventilation to polluted air by ventilating a cutting face working area in a tunnel. <P>SOLUTION: The ventilating equipment is provided with an exhaust duct 11 for forming an air passing passage supplying the polluted air in the cutting face working area to the side of a pit mouth 21 of the tunnel 2 and a blower 12 supplying the air of the exhaust duct 11. In addition, an expansion duct 13 is provided in a suction opening side in the exhaust duct 11. Furthermore, an auxiliary blower 16 supplying the air into the expansion duct 13 when ventilation working is performed is provided in a moving suction opening part 13A in the expansion duct 13. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a ventilation device in a tunnel for reducing the concentration of dust or harmful substances in tunnel construction, for example, toxic gases such as hydrogen sulfide and sulfur dioxide (hereinafter referred to as "pollutants"). .

[0002]

2. Description of the Related Art For example, when excavating a mountain tunnel or the like, a large amount of dust is generated along with the excavating work. If such dust remains inside the tunnel, it may impair the health of workers. Therefore, dust in the work area near the face (hereinafter referred to as the "face work area") is discharged to the outside of the tunnel. Ventilators for doing this are known. As such a ventilation device, there are generally a so-called air supply type ventilation device and an exhaust type ventilation device. Of these ventilation devices, the exhaust type ventilation device 40 shown in FIG.
Is provided with a short short blower air duct 41 provided in the face working area 22 inside the tunnel 2. A local blower 42 is provided at the inlet of the short air blow pipe 41, and air is introduced into the short air blow pipe 41. The air blown out from the air outlet 43 of the short air supply air duct 41 is blown toward the face 23. Further, the exhaust type ventilation device 40 includes an exhaust wind pipe 44 extending from the face working area 22 of the tunnel to the wellhead 21 at a position above the tunnel 2.
Is equipped with. A blower 45 is provided at the inlet of the exhaust air pipe 44, which is an opening on the face 23 side. Then, by driving the blower 45, the dust in the face working area 22 is discharged to the outside of the tunnel 2 through the exhaust wind pipe 44 together with the air blown from the blowout port 43 of the short air blow pipe 41. , The dust concentration in the tunnel 2 is reduced.

On the other hand, in the air supply type ventilation device 50 shown in FIG. 7B, in the upper position of the tunnel 2, the air supply air duct 5 extending from the wellhead 21 of the tunnel 2 to the face working area 22.
Have one. A blower 52 is provided at the inlet of the blower tube 51.
Is provided, and external clean air is introduced into the air blowing tube 51. The clean air introduced into the air blowing tube 51 is blown out from the air outlet 53 of the air blowing tube 51 and is blown to the face 23. A dust collector 54 is provided at a lower position in the face working area 22. A local blower 55 is provided on the pit 21 side of the dust collector 54, and an exhaust short pipe 56 is provided on the pit 21 side. Then, the air blown out from the air outlet 53 of the air blowing tube 51 blows out dust generated near the facet 23 to the rear. The blown air is collected by the dust collector 54 by the wind force of the local blower 55, and the dust is removed. Thereafter, the clean air from which dust has been removed is exhausted to the side of the wellhead 21 through the local blower 55 and the exhaust short pipe 56.

[0004]

By the way, in the conventional exhaust type ventilation device 40, the inlet of the exhaust air duct 44 is provided at a position, for example, 60 to 80 m away from the face 23. Generally, without a local blower, the air collected by the exhaust air duct is in the range of 2-4 times the diameter of the exhaust air duct. For this reason, the local blower 42 is provided so as to blow the air containing dust toward the inlet of the exhaust air duct 44, but if the inlet of the exhaust air duct 44 is installed near the face 23, the local blower 42 will be installed. Ventilation of the face working area 22 can be performed without providing. However, if the inlet of the exhaust air duct 44 is set in the vicinity of the face 23, the exhaust air duct 4 can be used, for example, when performing blasting work.
4 may be damaged.
There was a problem that 4 entrances could not be provided.

Further, in the air supply type ventilation device 50, the air containing a large amount of dust can be sent to the dust collector 54 when the air outlet 53 of the air supply air duct 51 is located closer to the face face 23. . However, if the air outlet 53 of the air blowing tube 51 is arranged in the vicinity of the face 23, the air blowing tube 51 may be damaged during the blasting work, so that the air blowing tube 51 may be located at that position. There was a problem that could not be placed.

Therefore, an object of the present invention is to simplify the device by eliminating the need for a local blower in ventilating the working area of the face in the tunnel, and further, to contaminate the air contaminated with pollutants (hereinafter referred to as " It is to provide a ventilation device capable of achieving good ventilation for "polluted air".

[0007]

SUMMARY OF THE INVENTION The present invention, which has solved the above-mentioned problems, is directed to a ventilating apparatus for a tunnel for ventilating the inside of a tunnel, in which contaminated air in a face working area of the tunnel is removed from the wellhead side of the tunnel. An exhaust air duct that forms a ventilation passage for supplying air to the exhaust air duct and a blower that blows air in the exhaust air duct are provided, and the inlet side of the exhaust air duct expands and contracts in the direction along the tunnel tunnel. A ventilator in a tunnel, wherein a telescopic air duct is attached, and an auxiliary blower for sending air into the telescopic air duct is provided at a moving suction port of the telescopic air duct.

In such a ventilator, by using the expandable air duct, the position of the air duct can be moved back and forth with respect to the face of the face depending on the type of face work. Therefore, for example, at the time of blasting work, the tip of the expandable air tube is retracted to prevent damage, and when sliding out and spraying work,
By bringing the tip of the expandable air duct close to the face of the face, damage to the expandable air duct can be prevented and good ventilation can be achieved.

An auxiliary blower for sending air into the expandable air duct is provided at the moving suction port of the expandable air duct. By installing this auxiliary blower, the negative pressure inside the expandable air duct can be removed. Therefore, as the expandable air duct, a lightweight vinyl pipe is used, but if the internal negative pressure is used, the flow path will be blocked. can do. Therefore, since it is possible to reduce the weight of the expandable air tube, it is possible to reduce the power of the drive mechanism for driving the expandable air tube.

Further, in a ventilation device in a tunnel for ventilating the inside of the tunnel, there is provided an air blowing tube having an air outlet for blowing air to a face working area of the tunnel, and the air blowing tube is blown. It has a pollutant removal device that removes pollutants contained in the air blown from the outlet, and an expandable air duct that expands and contracts in the direction along the tunnel's gallery is attached to the suction port side of the pollutant removal device. The ventilator in the tunnel is characterized in that an auxiliary blower for sending air into the telescopic air duct is provided at the moving suction port of the telescopic air duct.

With such a ventilator, even in a so-called air supply type ventilator, the position of the tip of the telescopic air duct can be determined according to the face work, and a lightweight telescopic air duct can be used. it can.

Further, it is desirable that a diffusion preventing member is provided at the moving suction port portion. By providing the diffusion prevention member in this way, it is possible to prevent the contaminants generated near the facet from being diffused to the tunnel entrance side. Therefore, the ventilation efficiency of the face working area can be improved.

[0013]

BEST MODE FOR CARRYING OUT THE INVENTION Preferred embodiments of the present invention will now be described in detail with reference to the drawings. The same elements will be denoted by the same reference symbols, without redundant description.

FIG. 1 is a side sectional view of a tunnel provided with a ventilation device for a tunnel according to a first embodiment of the present invention. As shown in FIG. 1, the ventilation device 1 in the tunnel according to the present embodiment is a so-called exhaust type ventilation device provided in the tunnel 2 and includes, for example, an exhaust air duct 11 made of vinyl. The exhaust air duct 11 has a face 2 on which a face work area 22 is set from a well 21 of the tunnel 2.
3 extends to a position before 3, and forms a ventilation path for feeding the contaminated air in the face working area 22 to the wellhead 21 side. The cutting face work area 22 is a region where work is performed in the vicinity of the cutting face 23, and its length is slightly different depending on the type of work, but is 30 m from the cutting face 23, for example.
It is set in the range of up to 100 m.

A blower 12 is provided at an inlet 11A which is an opening of the exhaust air duct 11 on the side of the face working area 22. The blower 12 introduces the contaminated air in the face working area 22 into the exhaust air duct 11 to blow air inside the exhaust air duct 11. The outlet of the exhaust air duct 11 is located outside the tunnel 2, and the air flowing through the exhaust air duct 11 is discharged to the outside of the tunnel 2 via the outlet of the exhaust air duct 11.

A telescopic air duct 13 is attached to the side of the blower 12 opposite to the exhaust air duct 11, and the telescopic air duct 1
3 is a moving suction port portion 13 on the opposite side of the blower 12
At A, a wind tube storage device 14 is provided. The expandable air tube 13 is made of, for example, vinyl, and the expandable air tube 13 is contracted by storing it in the air tube storage device 14 while folding it into a bellows shape. The telescopic wind tube 13 is extended by unwinding. Further, an air duct moving mechanism 15 is provided above the expandable air duct 13. Air tube moving mechanism 1
5 has a guide rail 15A provided along the tunnel 24 of the tunnel 2, and the guide rail 15A is provided with a plurality of movable suspenders 15B, 15B .... The mobile suspenders 15B, 15B ... Are attached at regular intervals in the longitudinal direction of the telescopic air tube 13. Then, the movable suspenders 15B, 15B, ... Are slid, and the retractable air duct 1 is accommodated in the air duct accommodating device 14 while reducing the distance between them.
3 can be contracted. On the contrary, the mobile lifting device 15
The telescopic air duct 13 can be extended by unwinding the air duct accommodating device 14 by widening the intervals of B, 15B, ... Further, the air duct housing device 14 has an inner cylinder 14A shown in FIG.
Is equipped with. Telescopic air tube 13 by air tube moving mechanism 15
When contracted, the contracted telescopic air tubes 13 are collected and stored around the inner cylinder 14A of the air tube housing device 14 (see FIG. 2B). In this way, the telescopic wind pipe 13 is connected to the tunnel 24.
It can be expanded and contracted in the direction along.

On the side opposite to the expandable air duct 13 in the air duct housing device 14, an auxiliary blower for sending air into the expandable air duct 13 and removing the negative pressure in the expandable air duct 13 during ventilation work. 16 are provided. The auxiliary blower 16 is a small-sized blower, and has an air blowing force enough to inflate the expandable air duct 13 at least when the expandable air duct 13 is completely extended. The auxiliary blower 16 includes a moving member 1 with a motor.
It is attached to 7. The motor-equipped moving member 17 includes wheels 17A that are movable along the guide rails 15A of the wind tube moving mechanism 15, and the wheels 17A are the connecting members 1.
It is connected to the auxiliary blower 16 via 7B. Also,
The wheel 17A is provided with a motor (not shown), and by driving this motor, the auxiliary blower 16 moves along with the wheel 17A along the guide rail 15A.

Next, the operation of the ventilation device according to this embodiment will be described.

In the face work area 22 of the tunnel 2, face work such as blasting work, slide-out work and concrete spraying (hereinafter referred to as "spraying") work is performed. The ventilator 1 removes the pollutants generated during the face work to reduce the concentration of the pollutants in the tunnel 2, particularly in the face work area 22.

When the blasting work is performed in the face working area 22, the telescopic air duct 13 is contracted, and the moving suction port 13A of the telescopic air duct 13 is kept away from the face 23.
The blasting work prevents the telescopic air tube 13, the auxiliary blower 16 and the like from being damaged. At this time, for example, the moving suction port portion 13A is preferably separated from the face 23 by about 60 to 80 m. When the expandable air tube 13 is contracted, most of the expandable air tube 13 is stored in the air tube storage device 14. Normally, when performing a blasting operation, the amount of pollutants (dust) generated is small, so that a satisfactory exhaust effect can be obtained even if the position of the expandable air duct 13 is slightly separated from the face 23.

After the blasting work is completed, the work proceeds to the sliding work and the spraying work, but when performing these works, a relatively large amount of pollutants are generated in the face work area 22. In order to effectively remove this contaminant, the motor provided on the motor-equipped moving member 17 is operated to set the auxiliary blower 16 to the face 2
The telescopic air tube 13 is extended by moving it in the direction of 3, and the moving suction port portion 13A is brought closer to the face 23. At this time, the telescopic air tube 1 stored in the air tube storage device 14
3 is taken out from the air tube storage device 14, and the telescopic air tube 13 is extended.

Specifically, the moving suction port portion 13A is brought close to the face surface 23, for example, within a range of 0.5 to 2 m to, for example, 1 m. Move to this extent Suction port 13A
By bringing the blades closer to the face 23, it is possible to effectively remove a large amount of contaminants that are generated during the sliding and spraying work. In addition, when performing these sliding and spraying operations, the risk of damaging the telescopic air tube 13 as in the blasting operation is small, so the telescopic air tube 13 is cut into the face 23.
Can be close enough to.

By the way, as the telescopic wind tube 13, for example, a telescopic steel tube or the like can be used.
Since such a steel pipe is heavy in weight and volume, it is necessary to use a large power and a moving mechanism having large strength to drive the steel pipe. In order to eliminate the need for such large power, it is preferable to use a lightweight wind tube made of vinyl or the like. However, since the vinyl air tube can be deformed so as to block the air flow passage by making the inside negative pressure, remove the negative pressure inside and make the inside positive to secure this flow passage. It is necessary to maintain pressure. Here, for example, when air is sent only by the blower 12 provided at the inlet 11A of the exhaust air duct 11, if a vinyl air duct is used as the telescopic air duct 13, the inside of the telescopic air duct 13 will be It becomes a negative pressure, and the flow path is blocked. On the other hand, in the ventilation device 1 according to the present embodiment, the auxiliary blower 16 is provided at the moving suction port portion 13A of the expandable air duct 13. Since the auxiliary blower 16 sends air to the extent that a ventilation path can be maintained in the expandable air duct 13, the negative pressure in the expandable air duct 13 can be removed.

Here, for example, the suction port 1 of the exhaust air duct 11
It is also conceivable that the blower 12 provided in 1A is provided in the moving suction port portion 13A of the expandable air duct 13 and the auxiliary blower 16 is not provided. However, since the blower 12 blows air into the exhaust air pipe 11 having a long distance, it needs to have a large output, and such a blower is usually large. Further, the blower provided in the moving suction port portion 13A of the expandable air tube 13 is moved by the air tube moving mechanism 15 as the expandable air tube expands and contracts. In order to move a large-sized blower, the wind pipe moving mechanism 15 also needs to have a large size and a large output, which is not preferable. In this respect, in the present embodiment, the auxiliary blower 16 provided in the movable suction port portion 13A only needs to cancel the negative pressure in the telescopic air duct 13 having a short distance.
Since its power is small, a small blower can be used. Therefore, as the moving member with motor 17 and the wind tube moving mechanism 15, compact ones can be used.

After the sliding and spraying work is completed, the blasting work is performed again. When performing the blasting work, the telescopic air tube 13 is contracted. In order to contract the telescopic air duct 13, the motor of the moving member 17 with a motor is driven to move the auxiliary blower 16 to the exhaust air duct 11 side. Then, the expandable air tube 13 is gradually stored in the air tube storage device 14, and the expandable air tube 13 contracts. Thus, the telescopic wind tube 13
And the blasting work is performed again with the auxiliary blower 16 kept away from the face 23. After that, by repeating this procedure, the tunnel excavation work proceeds, and the ventilation work during that time can be suitably performed.

By performing ventilation in this manner, it is possible to ventilate the face working area in good condition without providing a local blower.

Further, in the ventilation device 1 according to the present embodiment, as shown in FIGS. 3 and 4, the diffusion preventing member 18 may be provided on the face 23 side of the auxiliary blower 16. The diffusion prevention member 18 is the face 23 of the auxiliary blower 16.
It is attached to the tip on the side, and as shown in FIG. 4 (b), its shape is a semi-cylindrical shape so as to substantially cover the upper part of the tunnel 2 in cross section. And the diffusion prevention member 1
Below 8 is a space reserved for use as a work area. A blower opening 18A is formed in the center of the diffusion prevention member 18. The auxiliary blower 16 is provided on the side of the blast mouth 21 of the blower opening 18A, and the contaminated air in the vicinity of the face 23 is blown to the auxiliary blower 16 through the blower opening 18A. Further, at the position above the ventilation opening 18A, the rail opening 1
8B is formed. The rail opening 18B has a shape that is slightly larger than the cross-sectional shape of the guide rail 15A of the wind tube moving mechanism 15, and can penetrate the guide rail 15A.

Telescopic air tube 13 provided with an auxiliary blower 16
The moving suction port portion 13A has a larger air suction effect as it is closer to the face face 23, but may not be so close to the face face 23 due to reasons such as slipping out and spraying work. In such a case, by providing the diffusion preventing member 18, it is possible to prevent the contaminants generated in the vicinity of the face 23 from diffusing toward the wellhead 21.

Next, a second embodiment of the present invention will be described.

FIG. 5 is a side sectional view of a tunnel provided with a ventilation device for a tunnel according to a second embodiment of the present invention. As shown in FIG. 5, the ventilation device 3 in the tunnel according to the present embodiment is a so-called air supply type ventilation device provided in the tunnel 2, and includes, for example, an air supply air duct 31 made of vinyl. There is. The air blower pipe 31 is provided at a lower position in the tunnel 2 and extends from the outside of the tunnel 2 to a position near the wellhead 21 in the face working area 22. A blower 32 is provided on the outside of the tunnel 2 in the blower tube 31. This blower 32 introduces clean outside air into the tunnel 2 through the air blow pipe 31. In addition, the air outlet 3 of the air blowing tube 31
A pollutant removing device 33 is provided at a position slightly above 1A and slightly closer to the face 23. The pollutant removal device 33 has a function of removing pollutants such as dust from polluted air, for example, a dry type, a wet type, or an electric type dust collector equipped with a bag filter, and other toxic gases. A known device such as a separating device can be appropriately used.

An air blower (not shown) is provided inside the contaminant removing device 33 integrally with the contaminant removing device 33. By driving this blower, air is introduced into the pollutant removal device 33, and the pollutant removal device 33
The air from which the contaminants have been removed is exhausted from the exhaust port on the side of the pit 21 in the contaminant removing device 33. Here, if the air outlet 31A of the air blowing tube 31 is located slightly closer to the face 23 than the discharge port of the pollutant removal device 33, air is exhausted from the discharge port of the pollutant removal device 33. Thus, the air blown out from the air outlet 31A of the air blowing tube 31 flows in the direction of the face 23.
Therefore, the air outlet 31A of the air blowing tube 31 is located slightly closer to the face 23 than the outlet of the contaminant removing device 33.

Face face 23 of pollutant removal device 33
An expandable air duct 13 made of, for example, vinyl, similar to that of the first embodiment, is provided on the side, and an air duct storage device 14 is provided on the opposite side of the expandable air duct 13 from the contaminant removing device 33. There is. Further, an air duct moving mechanism 15 is provided above the expandable air duct 13. Furthermore, the air duct storage device 1
An auxiliary blower 16 for providing a positive pressure in the expandable air duct 13 is provided on the opposite side of the expandable air duct 13 in FIG. A moving member 17 with a motor for moving the auxiliary blower 16 is provided above the auxiliary blower 16.

In the ventilation device 3 according to this embodiment,
Air is supplied to the face working area 22 from the side of the pit 21 to contain contaminants such as dust in the face working area 22. The polluted air is introduced into the pollutant removal device 33 through the expandable air duct 13 by the air blowing force of the blower provided in the pollutant removal device 33, and the pollutant removed by the pollutant removal device 33 is cleaned. Air is discharged to the side of the wellhead 21. Therefore, it is possible to prevent the polluted air from being discharged to the tunnel working area 25 on the side of the mine mouth 21 of the face working area 22.

At this time, the moving suction port portion 13A of the expandable air duct 13 has a higher ventilation effect when it is closer to the face 23, but like the first embodiment, for example, when performing blasting work, the face of the face is cut. If the expandable air duct 13 is located near the surface 23, the expandable air duct 13 and the auxiliary blower 16 may be damaged. Therefore, when performing the blasting work, the telescopic wind tube 1
3 is contracted, and the auxiliary blower 16 and the expandable air duct 13 are kept away from the face 23. Then, when the blasting work is completed and the slide-out and spraying work is performed, the telescopic wind tube 1
3 is extended and the movable suction port portion 13 of the telescopic wind tube 13 is extended.
A is arranged at a position near the face 23, specifically, a position within a range of 0.5 to 2 m from the face 23. In this way, efficient ventilation can be performed.

Further, as in the first embodiment, since the auxiliary blower 16 is provided, it is possible to use the expandable air duct 13 made of vinyl, which is easy to deform but lightweight. Further, the auxiliary blower 16 may be of a type that can maintain a positive pressure in the expandable air duct, and therefore can be of a small power. Therefore, as the moving member with a motor 17 for moving the auxiliary blower 16, a compact member can be used.

Further, as shown in FIG. 6, the ventilation device 3
In the above, the diffusion preventing member 18 similar to that of the first embodiment may be provided on the face 23 side of the auxiliary blower 16. By providing such a diffusion prevention member 18,
Pollutants generated in the vicinity of the face 23 are used for the wellhead 21.
It can be prevented from diffusing toward the direction.

By providing the diffusion preventing member 18, the amount of air supplied near the face 23 can be reduced. Therefore, the pollutant removal device 3
The amount of air sucked into 3 can be reduced.
The amount Q of air sucked into the pollutant removal device 33 at this time can be expressed by the following equation (1).

[0038] Q = 60V / (At-Ab) ... (1)

Here, Q is the amount of air sucked by the pollutant removal device 33, V is the velocity of air in a portion other than the portion sandwiched between the face 23 and the diffusion preventing member 18, At is the cross-sectional area of the tunnel, Ab Is the area of the diffusion prevention member.

Here, the velocity V of the air in the portion other than the portion sandwiched by the facet 23 and the diffusion preventing member 18 is usually about 0.5 m / s or more, and the flow velocity of the air is higher than that on the floor side on the ceiling. The side tends to be faster.

Although the preferred embodiments of the present invention have been described above, the present invention is not limited to the above embodiments. For example, in the first embodiment, the air duct housing device 14 is provided adjacent to the auxiliary blower 16, but it may be provided adjacent to the blower 12. Similarly, in the second embodiment, the air duct housing device 14 can be provided adjacent to the contaminant removing device 33. Further, although the diffusion prevention member 18 has a plate shape in the present embodiment, the shape, size, etc. are not limited to this.

[0042]

As described above, according to the present invention, the amount of pollutants generated is minimized when the face work area is ventilated in order to reduce the concentration of pollutants such as dust in the face work area of the tunnel. However, ventilation can be performed efficiently. Further, since the auxiliary blower for removing the negative pressure in the expandable air duct is used, a vinyl tube or the like can be used as the expandable air duct. For this reason,
The weight of the entire device can be reduced, and the drive mechanism for expanding and contracting the expandable air tube can be simplified.

[Brief description of drawings]

FIG. 1 is a side sectional view of a tunnel provided with a ventilation device according to a first exemplary embodiment.

FIG. 2 (a) is a side view in the vicinity of an expanding and contracting air duct,
(B) is a side view near the contracting telescopic air tube.

FIG. 3 is a side sectional view of a tunnel provided with a ventilation device according to a modified example of FIG.

FIG. 4A is a side view of a main part of a ventilation device according to a modified example,
(B) is the front view.

FIG. 5 is a side sectional view of a tunnel provided with a ventilation device according to a second exemplary embodiment.

FIG. 6 is a side sectional view of a tunnel provided with a ventilation device according to a modified example of FIG.

FIG. 7A is a side sectional view of a tunnel provided with a conventional exhaust type ventilation device, and FIG. 7B is a side sectional view of a tunnel provided with a conventional air supply type ventilation device.

[Explanation of symbols]

1, 3 ... Ventilator 2 ... tunnel 11 ... Exhaust air tube 12 ... Blower 13 ... Telescopic air tube 13A ... Moving suction port 14 ... wind tube storage device 15 ... Air tube moving mechanism 16 ... Auxiliary blower 17 ... Moving member with motor 18 ... Diffusion prevention member 21 ... Wellhead 22 ... Face working area 23 ... Face

   ─────────────────────────────────────────────────── ─── Continued front page    (72) Inventor Mitsuru Yokoyama             Kashima-ken, 1-2-7 Moto-Akasaka, Minato-ku, Tokyo             Inside the corporation (72) Inventor Shinichi Tokaji             Kashima-ken, 1-2-7 Moto-Akasaka, Minato-ku, Tokyo             Inside the corporation F-term (reference) 3L058 BD01 BE08 BG05                 3L080 AE05

Claims (3)

[Claims] 1. A ventilation device in a tunnel for ventilating the inside of a tunnel, comprising: an exhaust air duct forming an air passage for feeding contaminated air in a face working area of the tunnel to a pit side of the tunnel; A blower that blows air in the exhaust air duct, and an expandable air duct that expands and contracts in a direction along the tunnel tunnel is attached to the intake port side of the exhaust air duct. A ventilation device in a tunnel, characterized in that an auxiliary blower for sending air to the is installed at the moving suction port of the telescopic wind pipe. 2. A ventilation device in a tunnel for ventilating the inside of a tunnel, comprising an air blowing tube having an air outlet for blowing air to a face working area of the tunnel, wherein the air blowing tube blows air. It has a pollutant removal device that removes pollutants contained in the air blown from the outlet, and a telescopic wind tube that expands and contracts in the direction along the tunnel's gallery is attached to the suction port side of the pollutant removal device. A ventilation device in a tunnel, characterized in that an auxiliary blower for sending air into the telescopic air duct is provided at a moving suction port of the telescopic air duct. 3. The ventilation device in the tunnel according to claim 1, wherein a diffusion prevention member is provided at the movable suction port portion.