JPH0422080Y2 - - Google Patents

Description

[Detailed explanation of the idea] This invention relates to a rotary blower.

Underground excavation work is carried out under adverse conditions such as exhaust gas from heavy machinery, welding hems, and in some places hydrogen sulfide gas is generated. For this reason, at the above-mentioned work sites, fresh air is brought in through ventilation ducts, and at the same time, the generated gas is quickly diluted and diffused.

However, with this type of conventional ventilation method, air is supplied only in a certain direction, which means that ventilation does not reach the entire site, resulting in areas where it stagnates.
Particularly at excavation sites with large underground areas, it has been difficult to effectively ventilate the entire site due to restrictions on the installation location and number of units.

Therefore, for example, it is possible to adopt the rotating wind barrel rotating device disclosed in Japanese Utility Model Publication No. 34-2347, but with this structure, the rotational force is obtained from the wind that collides with the rotating wind barrel. Therefore, the structure was complicated and the efficiency was not good.

This idea was created in view of the above-mentioned drawbacks of the conventional technology, and has a simple structure that allows fresh air to be moved and diffused over a wider area than before. The purpose is to reduce the number of machines.

In order to achieve the above object, this invention includes an elbow that is rotatably attached to the tip of the air duct, and an elbow that is formed separately from the elbow, is fixed to the inner periphery of the mounting base, and is rotatably attached to the elbow. The elbow has the same closed cross section as the duct, and its tip is inclined outward at a predetermined angle with respect to the axis of the duct. shall be.

Hereinafter, one embodiment of this invention will be described in detail using the drawings.

FIG. 1 shows an embodiment of the blower according to this invention.

In the figure, a blower 1 includes a blower 3 coaxially mounted on the upper part of a vertical duct 2 for blowing air, an elbow mounting attachment 4 fixed to the lower part of the vertical duct 2 by flange connection, and a lower part of the attachment 4. Rotatably mounted elbow 5
It is composed of.

A bearing portion 7 supported by a plurality of stays 6 is fixed at the center of the inner circumferential portion of the attachment 4 . The peripheries of a plurality of fixed wings 8 formed separately from the elbow 5 are fixed to the inner circumference of the elbow 5 on the mounting base side, and the fixed wings 8 have a shaft 9 protruding from the center thereof. It is attached by being rotatably supported by the bearing part 7.

The tip side of the elbow 5 is opened in an inclined manner outward at an angle of about 45° with respect to the axial center of the vertical duct 2.

With the above configuration, when air is sent from the blower 3 as shown by the arrow, the air flowing through the duct 2 and attachment 4 is changed in direction by 45 degrees within the elbow 5 and is discharged to the outside as shown by the chain arrow.

Moreover, at the same time, rotational force is applied to the fixed blade 8 due to wind pressure, and the blade 8 and the elbow 5 rotate about the shaft 9 as if swinging their heads.

Therefore, the air discharged from the elbow 5 spreads over a wide circular area centered on the duct 2.

Figure 2a shows an example where the blower 1 with the above configuration is installed at an excavation site, where 10 is an earth retaining wall, 11
12 is the ground that is being excavated, and 12 is the slab that was cast using the reverse pouring method.

With the rotary blower of the present invention, as mentioned above, fresh air is sent into the space at the excavation site with a relatively strong wind pressure due to the rotation of the elbow 5, and within a wide area as shown by the arrow, and due to the stirring effect of the rotation. ,
Gas generated within the space is quickly diluted and diffused.

On the other hand, in the conventional fixed type blower 20 shown in FIG. 2b, strong wind pressure is generated only directly below the duct 20a, and the air is blown only in a relatively narrow range shown by the arrow.

In addition, the rotating wind fuselage shown in Utility Model Publication No. 34-2347 does not have a fixed blade that applies rotational force to the elbow as in the invention of the present invention, but is installed at a position eccentric from the axis of the fixed wind fuselage. Since rotational force is applied to the rotating wind cylinder by causing the wind to collide with the axial-flow fan, the wind sent from the axial fan cannot be effectively diffused laterally.

That is, the plates that the wind collides with are each tilted upward toward the exhaust stack from which the wind is blown.
Moreover, the rotating wind cylinder rotates in the opposite direction to the direction of the wind blown out from the exhaust stack, and under these conditions, the plate rotates at the moment the wind blown out from the axial fan collides with the plate. Since the plate is tilted upward, the surface that the wind actually collides with is further back than it would be if it did not rotate, which weakens the force of the wind colliding with it. .

This phenomenon occurs on the entire surface of the board,
When the colliding force is weakened in this way, the wind sent out from the axial fan has a strong tendency to travel straight, making it difficult to disperse the wind in all directions.

For example, if we assume that the wind hits a windmill, the windmill will rotate, but the direction of the wind will hardly change and it will go straight. However, it is likely to occur.

On the other hand, in the present invention, when the fixed blade 8 is hit by the wind, the fixed blade 8 rotates, after which the wind travels almost straight, and the wind that travels straight hits the inner surface of the elbow 5 and is changed direction. Can be sufficiently distributed in all directions.

Here, when the straight wind hits the inner surface of the elbow 5, since the elbow 5 is rotated by the fixed blades 8, the same phenomenon as in the device of the above publication may occur, but the elbow of the present invention 5 has the same closed cross section as the duct, so even if one surface located in the direction of rotation escapes at the moment the wind hits, the other surface approaches the wind in the opposite direction. The situation is not the same as the one above, but the wind that has traveled straight changes its direction to the side along the slope of the elbow 5, and the direction of the changed wind is efficiently and sufficiently dispersed in all directions by the rotation of the elbow 5. Ru.

Further, in the swirling wind cylinder of the above-mentioned publication, the exhaust pipe is eccentric and a plurality of exhaust pipes are provided, which makes the structure complicated and reduces efficiency, but the present invention does not have such drawbacks.

As explained in the examples above, in this invention,
Because the movement range of fresh air is greatly expanded, when used at an excavation site, the gas generated within the space can be diluted and diffused quickly and efficiently, compared to when using a conventional fixed blower. The number of installed units can be reduced.

In addition, in this invention, the elbow is rotated via fixed wings that are rotated by wind pressure, so there is no need to use any other power, and the structure is simple.

[Brief explanation of drawings]

Fig. 1 is a half-sectional side view of the blower according to this invention, Fig. 2a is an explanatory diagram showing the wind direction when the same blower is used at an excavation site, and Fig. 2b is a diagram showing the wind direction when the same blower is used at an excavation site. It is an explanatory view showing wind direction. 1...Blower, 2...Vertical duct, 3...Blower, 4...Attachment, 5...Duct, 6...
...Stay, 7...Bearing section, 8...Fixed wing, 9...
Axis, 10... Retaining wall, 11... Ground being excavated, 1
2... Floor slab, 20... Conventional blower, 20a...
duct.

Claims (1)

[Scope of utility model registration request] The elbow consists of an elbow rotatably attached to the tip of the air duct, and a fixed wing that is formed separately from the elbow and fixed to the inner periphery of the mounting base to apply rotational force to the elbow. A rotary blower having the same closed cross section as the duct, and having its tip inclined outward at a predetermined angle with respect to the axis of the duct.