JP3538252B2 - Two-stage air filtration device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a two-stage air filtration device comprising a two-stage air filtration section constituted by a double filter medium.
In particular, the present invention relates to a two-stage air filtration device capable of improving the operation efficiency of a blower or the like while maintaining the collection efficiency of dust or the like at a required value.

[0002]

2. Description of the Related Art As a conventional two-stage air filtration device, there is known an endless automatic winding type air filtration device described in Japanese Patent Publication No. 64-4809.

[0003] This endless automatic winding type air filtering apparatus will be described with reference to FIG. A portion extending from a to b inside the filter body 1 is an air discharge unit 2. The upper part of the filter body 1 is a ceiling part 3. The part extending from c to d is the air suction part 4. An endless non-woven filter medium 6 is wound around the inside of the filter body 1.
The filter medium 6 fed out from the part a of the air discharge part 2 is bridged in a zigzag shape until reaching the part b to secure a wide filtration area. The air suction portion 4 is linearly arranged from the portion c to the portion d.

[0004] With the above configuration, the air flowing from the air suction part 4 side passes through the filter medium 6 bridged from the c part to the d part of the air suction part 4, so that a large amount of dust and the like in the air is generated. Part is captured. Next, the filter medium 6 bridged from the part a to the part b of the air discharge part 2 captures the remaining dust and the like, and causes the air to flow downstream.

Further, the air to be cleaned is passed only through the filter medium on the air suction section 4 side to capture dust and the like, and is flowed from both sides to the downstream side without passing through the filter medium 6 on the air discharge section 2 side (collection). There is also a filter cloth for dust "Jitsuho 5-34730" (FIG. 4 (b)).

[0006]

By the way, in the endless self-winding type air filtering device having the above-mentioned structure, the air suction portion 4 is provided.
All air from the upstream side flows into the inside from the air suction part 4 and entirely flows out from the air discharge part 2. For this reason, the pressure loss (air resistance) between the upstream side and the downstream side of the filtration device is constant, and the energy required for blowing air is also constant.

[0007] However, the required dust-collecting ability has a certain range and is not constant. For example, it is necessary to increase the trapping capacity in air with a large amount of dust and the like, and it is sufficient to reduce the trapping ability in air with little dust and the like. For this reason,
An imbalance may occur between the energy required to blow air through the filtration device and the trapping capacity. That is,
When the amount of dust and the like in the air is small and it is not necessary to increase the trapping capacity so much, it is a waste of energy to double the filter medium 6 and pass all the air through the filter medium 6. Conversely,
When it is necessary to maintain a high collecting capacity, it is necessary to sufficiently collect dust and the like with the double filter medium 6.

Further, a filter cloth for dust collection (Japanese Utility Model Publication No. 5-4733)
In the case of 0), the energy required for blowing the air is small, but since the trapping ability is low, only a low degree of air purification can be obtained.

For this reason, it is not possible to efficiently adjust the required ability to collect dust and the like and the ability to blow air, resulting in problems such as poor air purification and large energy loss. is there.

The present invention has been made in view of the above problems, and it is possible to minimize the energy loss while maintaining the ability to collect dust and the like in the air at a required value. It is an object to provide a staged air filtration device.

[0011]

According to a first aspect of the present invention, a two-stage air filtration device is provided in which a continuous filter medium is folded back to form a double filter medium. In the two-stage air filtration device that constitutes a filtration unit, an air bypass is provided in one of the upstream filter medium and the downstream filter medium, and air that has passed through the upstream filter medium and air that has been bypassed to the air bypass circuit. And a part of the air passed through the upstream filter medium is passed through the downstream filter medium, and the remaining air is bypassed by the air bypass circuit.

[0012] A two-stage air filtration device according to a second aspect of the invention is characterized in that an air amount adjusting means for adjusting an amount of air diverted to the air detour is provided.

[0013]

According to the first aspect of the present invention, a part of the air from the upstream side is passed through the upstream filter medium or the downstream filter medium by the air bypass circuit provided in one of the upstream filter medium and the downstream filter medium to leave the remaining air. By air detour. At this time, all of the air from the upstream side passes through the upstream side filter medium or the downstream side filter medium that does not have the air bypass.

When air with little dust or the like flows in, a part of the air is diverted from the air bypass to reduce air resistance. As a result, the ability to collect dust and the like can be maintained at a required value, and energy loss can be minimized.

According to the second aspect, the amount of air to be diverted to the air bypass is appropriately adjusted by the air amount adjusting means provided in the air bypass. This makes it possible to more appropriately adjust the ability to collect dust and the like and the energy loss.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of a two-stage air filter according to the present invention will be described below with reference to the accompanying drawings.

[Configuration] FIG. 1 is a front sectional view showing a schematic configuration of a two-stage air filtration device according to the present embodiment, and FIG. 2 is a side sectional view showing a schematic configuration of the two-stage air filtration device.

In the figure, reference numeral 12 denotes a casing constituting an outer shell of the two-stage air filtration device 11. The whole of the two-stage air filtration device 11 is formed in a substantially rectangular parallelepiped shape. An air suction part 13 is formed on the upper side of the housing 12, and an air discharge part 14 is formed on the lower side.

The air suction part 13 has an endless filter medium 15.
Is installed. The endless filter medium 15 is formed in an annular band shape by connecting respective ends of the band-shaped filter medium to each other. Rollers 16 and 17 are arranged inside the both ends of the air suction portion 13 so as to face each other. An endless filter medium 15 is wound around these rollers 16 and 17 so that they can be rotated. Of the endless filter medium 15, the upstream filter medium (outer surface) is a first filtration surface 15A, and the downstream filter material (inner surface) is a second filtration surface 15B, thereby forming a two-stage air filtration unit. ing.

As a means for rotating the rollers 16 and 17, a crank (not shown) which is attached to one of the rollers 16 and 17 and rotated manually, a drive motor (not shown) which automatically rotates the roller, and the like are used. . Further, at a position in the housing 12 facing the endless filter medium 15, a removing means (not shown) for removing dust or the like adhering to the front and back surfaces of the endless filter medium 15 (for example, by suctioning or scraping off) Means). This removal means,
The endless filter medium 15 is provided on both the front surface and the back surface.

Both ends in the width direction (left and right sides in FIG. 1) of the endless filter medium 15 bridged over the rollers 16 and 17 are open, and the air that has passed through the first filtration surface 15A passes through the second filtration surface 15B. The endless filter medium 15 flows into the housing 12 while passing through the housing 12. Openings on both sides of the endless filter medium 15 constitute an air detour.

Opening plates 18 and 19 for opening and closing the openings are provided at both sides of the endless filter medium 15 in the housing 12. Each of the open / close plates 18 and 19 is formed in a rectangular shape so as to cover both side openings of the endless filter medium 15, and the surface thereof is a blind plate without punching or the like and having no air permeability. At positions facing the openings on both sides of the endless filter medium 15, there are provided opening and closing plate moving support means (not shown) for supporting and moving the opening and closing plates 18 and 19 to open and close the openings on both sides of the endless filter medium 15. As the opening / closing plate moving support means, a means for manually moving each of the opening / closing plates 18 and 19 or a means for automatically moving each of the opening / closing plates 18 and 19 by a hydraulic cylinder, an electric motor, or the like is used. The opening and closing plates 18 and 19 are moved by the opening and closing plate moving support means, so that the openings on both sides can be continuously controlled from fully open to fully closed. The opening / closing plate moving support means and the opening / closing plates 18 and 19 constitute an air amount adjusting means for adjusting the amount of air diverted to the air detour.

At the lower position of each of the open / close plates 18 and 19 in the housing 12, together with each of the open / close plates 18 and 19, an endless filter medium 15 is provided.
Are provided with lower opening / closing plates 21 and 22 for opening and closing both side openings. The lower opening / closing plates 21 and 22 are set to have substantially the same length as the inside dimensions of the housing 12 by a blind plate, and have an L-shaped cross section. Below the lower opening / closing plates 21 and 22, a lower opening / closing plate moving support means (not shown) having the same configuration as that of the opening / closing plates 18 and 19 is provided. The lower opening and closing plates 21 and 22 are controlled to be opened and closed by the lower opening and closing plate moving support means. As the lower opening / closing plate movement supporting means, a manual device, an automatic device, or the like is used as in the case of the opening / closing plate movement supporting means. The lower end of the endless filter medium 15, which is bridged between the rollers 16, 17, is provided at the lower side of the opening on both sides.
Frames 12A and 12B are provided to cover the lower side. The lower opening / closing plates 21 and 22 are in contact with the inner side wall of the housing 12 and the frames 12A and 12B to close the openings on both sides of the endless filter medium 15. The lower opening / closing plate moving supporting means and the lower opening / closing plates 21 and 22 constitute the same air amount adjusting means as the opening / closing plate moving supporting means and the opening / closing plates 18 and 19.

The two-stage air filtration device 11 having the above-described configuration is interposed in the middle of an air flow path through which air to be cleaned flows, and the air to be cleaned by a blower (not shown) is forced into the air flow path. Is blown out.

[Operation] The air sent by the blower is caused to flow into the air suction portion 13 of the two-stage air filtration device 11. When the air that has flowed into the air suction portion 13 from the upstream side passes through the first filtration surface 15A of the endless filter medium 15,
Most of the dust and the like are removed by the filtration surface 15A. The air that has passed through the first filtration surface 15A flows into the space between the first filtration surface 15A and the second filtration surface 15B.

When the opening / closing plates 18 and 19 close the openings on both sides of the endless filter medium 15, all of the inflow air flows out of the air discharge section 14 through the second filtration surface 15B. Then, at this time, dust and the like that could not be removed by the first filtration surface 15A are removed.

On the other hand, the concentration of air dust or the like that must be removed by the two-stage air filtration device 11 depends on the environment in which the two-stage air filtration device 11 is used, the condition during operation of the two-stage air filtration device 11, and the like. In some cases, it may be sufficient to filter the air only with the first filtration surface 15A, and sometimes it may be necessary to filter the air with both the first filtration surface 15A and the second filtration surface 15B.

In such a situation, the first filtration surface 15A and the second filtration surface 15B
It is wasteful to double-filter with the filter, and the burden on the blower is large. In this case, the opening and closing plates 18 and 19 are moved by the opening and closing plate moving support means to make the endless filter medium 15.
Open both sides of the opening.

The opening of the open / close plates 18 and 19 is appropriately adjusted from a slight opening to a full opening. Specifically, it is appropriately adjusted in consideration of the dust concentration in the air and the like. That is, when the amount of dust in the air is small, it is not necessary to pass air through both the first filtration surface 15A and the second filtration surface 15B,
Fully open 8,19. As a result, most of the air from the upstream side flows through the first filtration surface 15A, and then flows out from the openings on both sides of the endless filter medium 15, which is an air bypass, to the air discharge unit 14 side.

When the amount of dust in the air is large to some extent, the opening degree of the opening / closing plates 18 and 19 is adjusted so that a proportion of the air passing through the first filtering surface 15A is passed through the second filtering surface 15B in accordance with the amount. To adjust. That is, in a state where the air that has been cleaned through the second filtration surface 15B and the air that has passed through only the first filtration surface 15A are mixed in the air discharge unit 14, the dust concentration is within a required value. Next, the opening and closing of the opening and closing plates 18 and 19 are controlled appropriately.

As a result, the air resistance is not increased more than necessary, and the air can be efficiently cleaned with small energy.

In the above-described operation, a case has been described in which the opening and closing of both sides of the endless filter medium 15 is controlled by only the opening and closing plates 18 and 19. However, the opening and closing of both sides by only the lower opening and closing plates 21 and 22 is controlled. You may do so. Alternatively, the control may be performed using both the open / close plates 18 and 19 and the lower open / close plates 21 and 22.

[Effect] Since the lowest air resistance can be obtained with the dust collection efficiency maintained at a required value, the blower and the like can be operated with high operation efficiency. Energy collection can be performed efficiently while minimizing energy loss.

Since the two-stage air filtration device 11 can freely adjust the air resistance, the two-stage air filtration device 11 can be installed with the air resistance value adjusted to the capacity of the blower or the like. As a result, it can be used as various air filtration devices installed in various buildings and the like.

[Modifications] (1) In the above embodiment, the opening / closing plates 18 and 19 and the lower opening / closing plates 21 and 22 were formed as blind plates, but the surfaces were punched or the like so as to have air permeability. Is also good. In this case, the opening / closing plates 18 and 1 are provided without providing the opening / closing plate moving support means.
9 and the like may be directly fixed to both side openings of the endless filter medium 15, and the size of the hole may be appropriately adjusted to control the air flow rate.

(2) In the above-described embodiment, the air detour which bypasses the second filtration surface 15B is formed by providing both sides of the endless filter medium 15, but the air detour which bypasses the first filtration surface 15A is formed. You may. In this case, the air suction portion 13
An air detour is formed by leaving a gap between the filter member 15 and the endless filter medium 15, and the second filter surface 15B and the air discharge portion 14 side are closed. As a result, air that has flowed in from both or one of the first filtering surface 15A and the air detour is separated from the second filtering surface 15B.
Through the air outlet 14 side. Then, the opening / closing plates 18 and 19 are provided in the air bypass, and the opening and closing of the air bypass is controlled as needed.

[0037]

As described above, according to the present invention,
The following effects are obtained.

(1) An air bypass is provided in one of the upstream filter medium and the downstream filter medium, and the air passed through the upstream filter medium and the air bypassed through the air bypass circuit are combined and flow into the downstream filter medium. Or, since a part of the air that has passed through the upstream filter medium is passed through the downstream filter medium and the rest is bypassed by the air bypass, the air blower and the like are kept high while maintaining the collection efficiency of dust and the like required for the filter medium. Operational efficiency can be maintained. That is, energy loss can be minimized. As a result, it is possible to achieve mutually contradictory functions.

(2) Since the air amount adjusting means for adjusting the amount of air diverted to the air detour is provided, the amount of air diverted to the air detour can be finely adjusted, and the collection efficiency required for the filter medium And high operating efficiency of a blower or the like can be compatible with each other.

[Brief description of the drawings]

FIG. 1 is a front sectional view showing a schematic configuration of a two-stage air filtration device of the present invention.

FIG. 2 is a side sectional view showing a schematic configuration of a two-stage air filtration device of the present invention.

FIG. 3 is a side sectional view showing a conventional air filtering device.

[Explanation of symbols]

11 ... two-stage air filtration device, 12 ... housing, 13 ... air suction part, 14 ... air discharge part, 15 ... endless filter medium, 15A
... 1st filtration surface, 15B ... 2nd filtration surface, 16, 17 ... roller, 18, 19 ... opening / closing plate, 21, 22 ... lower opening / closing plate.

────────────────────────────────────────────────── (5) Continuation of the front page (56) References JP-A-5-66039 (JP, A) JP-A-51-117374 (JP, A) JP-A-8-173739 (JP, A) JP-A-49-1979 45469 (JP, A) JP-A-2-2422029 (JP, A) JP-A-3-68414 (JP, A) JP-A-5-317627 (JP, A) JP-A-3-77141 (JP, U) Jpn. Hei 5-34730 (JP, Y2) (58) Fields investigated (Int. Cl. ⁷ , DB name) B01D 46/18 B01D 46/00

Claims (2)

(57) [Claims] 1. A two-stage air filtration device comprising a continuous filter medium folded back to form a double filter medium and a two-stage air filtration unit comprising an upstream filter medium and a downstream filter medium of the double filter medium. An air bypass is provided in one of the filter media and the downstream filter media, and the air passed through the upstream filter media and the air bypassed through the air bypass are combined and flowed into the downstream filter media, or passed through the upstream filter media. A two-stage air filtration device, wherein a part of air is passed through a downstream filter medium and the rest is diverted by an air bypass. 2. The two-stage air filtration device according to claim 1, further comprising an air amount adjusting means for adjusting an amount of air diverted to the air detour.