JP7258326B2 - Dust filter cleaning device and dust collector - Google Patents

Description

TECHNICAL FIELD The present invention relates to an apparatus for cleaning a dust filter attached to a dust collector for removing dust in the atmosphere, and a dust collector using the apparatus.

As a device of this type, the applicant has proposed a technique described in Patent Document 1. According to the technique described in Patent Document 1, it is possible to obtain a cleaning effect superior to that of a dust collection filter cleaning device that uses the wind pressure of compressed air to push out dust adhering to the filter.

JP 2016-13531 A

However, since the details of the principle of why the device described in Patent Document 1 is highly effective in removing dust are unclear, there is room for further improving the cleaning effect.

SUMMARY OF THE INVENTION The present invention has been made to solve the above-described problems, and an object thereof is to provide a dust collection filter cleaning device with a higher cleaning effect than the conventional device.

The present invention can be implemented as the following application examples. In addition, the reference numerals in parentheses and supplementary explanations in this column indicate the correspondence with the embodiments described later in order to help the understanding of the present invention, and do not limit the present invention in any way. .

[Example of application]
A dust collection filter cleaning device (1) according to the present invention is a dust collection filter cleaning device for cleaning a dust collection filter (23) mounted in a dust collection device,
a valve chamber (14), a tank chamber (15) that communicates with the valve chamber and is filled with pressurized gas, and communicates with the valve chamber (14) and stores the gas released from the tank chamber (15). a casing (11) having a nozzle (16) for ejecting toward the dust collection filter (23);
a diaphragm (12) housed in the valve chamber (14);
The valve chamber (14) has a circular shape in a plan view, is formed so that the central portion of the ceiling is high, and protrudes upward from the bottom surface so as to surround the opening of the nozzle (16). A planarly annular valve seat (18) on which the formed diaphragm (12) is placed is formed,
The tank chamber (15) is formed annularly in plan view so as to surround the valve chamber (14),
A gas conduit (17) is formed in the casing (11) for communicating between an opening provided in the ceiling of the valve chamber (14) and the exterior of the casing (11),
The diameter of the gas conduit (17) is smaller than the diameter of the nozzle (16), and the gas conduit (17) is configured to switch between charging and discharging of the pressurized gas into and out of the gas conduit (17). 17) is formed in a size larger than the diameter of the opening of the casing (11) side of the electromagnetic valve (13) attached to the side of the opening communicating with the outside of the casing (11),
The diaphragm divides the valve chamber into an upper space (C1) having the same pressure as the gas conduit and a lower space (C2) having the same pressure as the tank chamber. When the pressure is higher than the pressure in the space, the peripheral edge lowers to allow the upper space and the tank chamber to communicate with each other to guide the introduced gas into the tank chamber. The gist is that when the pressure is lower than the pressure in the lower space, communication between the gas conduit and the tank chamber is closed and the nozzle is opened by separating from the valve seat.

With such a configuration, the cleaning effect can be enhanced more than the conventional one. Although the details of the principle behind how the cleaning effect can be enhanced are unclear, it has been demonstrated through experiments that the effect can be enhanced.

It is an end elevation which represents a dust collection filter cleaning device typically. It is an end elevation showing the state of a diaphragm at the time of introducing pressurized gas. FIG. 4B is an end view showing the state of the diaphragm when pressurized gas is released; It is an end elevation showing the modification of a valve-seat part. It is an end elevation showing the modification of a nozzle. It is a sectional view showing a dust collector typically.

(First embodiment)
Hereinafter, a dust collection filter cleaning device 1 as an embodiment of the present invention will be described with reference to the drawings as appropriate.
First, the configuration of the dust collection filter cleaning device 1 will be described with reference to FIGS. 1 to 6. FIG. FIG. 1 is an end view schematically showing the dust collection filter cleaning device 1 of this embodiment (the electromagnetic valve is not an end view). FIG. 2 is an end view showing the state of the diaphragm when pressurized gas is introduced (the electromagnetic valve is not an end view). FIG. 3 is an end view showing the state of the diaphragm as pressurized gas is released (the electromagnetic valve is not an end view). FIG. 4 is an end view showing a modification of the valve seat portion (the electromagnetic valve is omitted). It is an end elevation showing the modification of a nozzle (an electromagnetic valve is omitted). FIG. 6 is a schematic cross-sectional view of a dust collector to which the dust filter cleaning device 1 is applied (some parts are not cross-sectional views, such as the dust filter, the electromagnetic three-way valve, and the intake fan).

The dust collection filter cleaning device 1 is mainly composed of a casing 11 , a diaphragm 12 and an electromagnetic three-way valve 13 .

The casing 11 has a substantially rectangular parallelepiped shape and is composed of two parts 111a and 111b. The two parts 111a and 111b are bolted together by bolts (not shown). A valve chamber 14 , a tank chamber 15 , a nozzle 16 and a gas conduit 17 are formed inside the casing 11 .

The valve chamber 14 has a circular shape in a plan view, and the ceiling has a so-called dome shape obtained by cutting a sphere along a plane. In addition, in this embodiment, although it is dome-shaped, it is not limited to this, as long as the central portion of the ceiling is high. The bottom surface of the valve chamber 14 is substantially flat, and an annular valve seat 18 is formed in the center of the bottom surface at a position one step higher than the bottom surface.

Although not shown, a grid-like crosspiece for supporting the diaphragm 12 is provided inside the valve seat 18 . This is to prevent the diaphragm 12 from bending because the pressure in the upper space C1 of the valve chamber 14 is considerably higher than the pressure inside the nozzle 16 when the tank chamber 15 is filled with pressurized gas. However, the crosspiece itself does not play a role in cleaning the dust collection filter 23, but rather acts as a resistance when the gas flows, so it is better to have as few crosspieces as possible.

As shown in FIG. 1, the valve seat 18 may have a shape in which only the portion in contact with the diaphragm 12 protrudes upward from the bottom surface, but as shown in FIG. You may make it By doing so, the resistance when the gas discharged from the tank chamber 15 flows into the nozzle 16 can be reduced.

The tank chamber 15 communicates with the side surface of the valve chamber 14 . The tank chamber 15 is a space filled with pressurized gas introduced from a gas conduit 17, which will be described later. The tank chamber 15 is formed in an annular shape in plan view so as to surround the valve chamber 14 .

In a conventional dust collection filter cleaning device (Patent Document 1), a substantially rectangular parallelepiped tank chamber is provided laterally of a valve chamber and slightly downward in a predetermined direction. As a result, there will be places near and far between the tank chamber and the nozzle. Since the nozzle is the final outlet of the gas in the tank chamber, the difference in the distance to the outlet causes a long time from when the gas in the tank chamber starts to be discharged until the discharge is completed. In order to enhance the cleaning effect of this device, the inventor believes that it is important to minimize the time from when the gas in the tank chamber starts to be released until the release is completed, and to make the gas flow into the nozzle at once. As a result of earnest experiments, this shape was invented.

By arranging the tank chamber 15 to surround the valve chamber 14, the tank chamber 15 and the nozzle 16 can be brought as close as possible. Moreover, since the gas in the tank chamber 15 is discharged toward the nozzle 16 from all directions on the plane, the gas in the tank chamber 15 can flow into the nozzle 16 at once.

Further, in the conventional dust collection filter cleaning device (Patent Document 1), the gas discharged from the tank chamber is once directed upward, changed 180 degrees at the inlet of the nozzle, and is jetted downward. However, in the shape of the present embodiment, since the tank chamber 15 communicates with the side surface of the valve chamber 14, it is only necessary to change the direction by approximately 90 degrees, and the gas released from the tank chamber 15 flows into the nozzle 16. It can reduce the resistance at the time of inflow.

It has been confirmed by experiments that the dust collection filter cleaning device 1 according to the present embodiment, in which the tank chamber 15 is shaped as described above, has a higher cleaning effect than the conventional one, but the details of the principle are still unknown. There are many points. The inventor believes that this is because the pressure wave can be generated more strongly.

Nozzle 16 is a straight tube nozzle having an inlet opening inside valve seat 18 and a downwardly extending tubular portion. The lower end of the tubular portion is an open end. The nozzle 16 receives the gas released from the tank chamber 15 via the valve chamber 14 and jets it toward the dust collection filter 23 .

For the diameter and length of the nozzle 16, the maximum pressure of the pressure wave ejected from the open end of the nozzle 16 is measured, and the measured maximum pressure is equal to or greater than a predetermined value.

The top of the ceiling of the valve chamber 14, the center of the diaphragm 12, the center of the valve seat 18, and the central axis of the nozzle 16 are desirably coaxial, which is the case in this embodiment as well.

A conventional dust collection filter cleaning device (Patent Document 1) also has a tubular nozzle called an expansion part, but its role is not necessarily clear.

In the case of a straight pipe nozzle like this embodiment, the gas flowing into the nozzle is compressed and stressed by the resistance of the air inside the nozzle that cannot diffuse, in addition to the effect of expanding the gas and increasing the flow velocity. I thought that it might have the effect of creating a shock wave and releasing it at the nozzle exit. As a result of earnest experiments, the inventors discovered that the diameter and length of the nozzle are important for improving the performance of the dust collection filter cleaning device, and completed the present invention.

However, it is still unclear what influences the tank capacity, pressure, route to the nozzle, etc. as factors for determining the diameter and length of the nozzle. Therefore, the nozzle diameter and length cannot be calculated.
Moreover, even if the principle is clarified in detail, the theoretically obtained dimensions are for the case where the gas is a perfect fluid, so ultimately, they should be adjusted by experiments using an actual machine.

Further, if the speed at which the gas flows from the valve chamber 14 into the nozzle 16 is subsonic, the nozzle may be tapered to accelerate the gas flow. However, a converging nozzle cannot generate a supersonic flow at its outlet, and a converging divergent nozzle must be used to generate a supersonic flow from a subsonic flow. Therefore, the shape of the nozzle may be a tapering and diverging nozzle (also called Laval nozzle, critical nozzle, sonic nozzle, etc.).
However, it is not essential in the present invention to adopt such a method in determining the diameter and length of the nozzle 16. FIG.

The gas conduit 17 is a space formed in the casing 11 that communicates an opening provided at the top of the ceiling of the valve chamber 14 with the outside of the casing 11 . The gas conducting path 17 is configured by a through hole passing straight upward from the top of the ceiling of the valve chamber 14 .
The diameter of the gas conducting path 17 is determined by measuring the maximum pressure of the pressure wave ejected from the open end of the nozzle 16, and adopting the diameter of which the measured maximum pressure is equal to or greater than a predetermined value.
In this embodiment, the maximum pressure of the pressure wave ejected from the open end of the nozzle 16 is measured. Measure the pressure change in the tank chamber 15 or the gas conduction path 17 when may be adopted.

The electromagnetic three-way valve 13 is directly attached to the casing 11 with the gas introduction hole (not shown) aligned with the opening (not shown) of the gas conduit 17 provided outside the casing 11. there is

In the conventional dust collection filter cleaning device (Patent Document 1), the diameter of the gas conduit is substantially the same as the diameter of the nozzle. However, it was found that the greater the volume of the gas conduit, the lower the cleaning effect of this device. This is because when the gas conduit is filled with pressurized gas and the gas conduit is opened to the atmosphere, the larger the volume, the longer it takes for the gas in the gas conduit to be discharged. , It was thought that it took time for the diaphragm to completely separate from the valve seat.

Therefore, the inventor conducted extensive experiments and found that the smaller the volume of the gas conduit 17, the shorter the time for the gas in the tank chamber 15 to be discharged. As a result, the inventors have confirmed that the gas flow in the tank chamber 15 is prolonged, and the present invention has been completed.

Also, in the conventional dust collection filter cleaning device (Patent Document 1), the three-way valve was attached to the tip of the hose connected to the opening of the gas conduit, but this is because the volume of the gas conduit is increased. It was the same as and lowered the cleaning effect. It has also been found to have an even worse effect if the hose is elastic.

Therefore, the electromagnetic three-way valve 13 is directly attached to the casing 11 . The reason why the electromagnetic system is used is that when the gas conduit 17 is filled with pressurized gas and the gas conduit 17 is opened to the atmosphere, the pressurized gas in the gas conduit 17 can be discharged in an extremely short time. This is because there is a possibility that the valve cannot be opened at once if it is done manually. If it is an electromagnetic type, it can be opened at once without fail. In this embodiment, a three-way valve is used, but only the valve on the discharge side may be electromagnetically operated.

It has already been confirmed that the dust collection filter cleaning device 1 according to the present embodiment, in which the gas conduit 17 and the electromagnetic three-way valve 13 are configured as described above, has a higher cleaning effect than the conventional device. There are still many unknown points. The inventor believes that this is because the pressure wave can be generated more strongly. However, such configuration of the gas conduit 17 and the electromagnetic three-way valve 13 is not essential in the present invention.

Diaphragm 12 is housed in valve chamber 14 . The diaphragm 12 is a disc-shaped diaphragm that elastically deforms like a disc spring. Diaphragm 12 rests on valve seat 18 and is biased slightly downward by abutting the ceiling of valve chamber 14 .

In this embodiment, the valve seat 18 is made of hard rubber, but for example, a metal core (not limited to metal) may be inserted in the portion to be placed on the valve seat 18 to prevent bending. In this way, the crosspieces on the inside of the valve seat 18 can be eliminated or at least reduced.

The diaphragm 12 divides the valve chamber 14 into an upper space C<b>1 having the same pressure as the gas conduit 17 and a lower space C<b>2 having the same pressure as the tank chamber 15 . When the pressure in the upper space C1 is higher than the pressure in the lower space C2, as shown in FIG. 2, the peripheral edge of the diaphragm 12 is lowered so that the gas conduit 17 and the tank chamber 15 are communicated with each other, and the nozzle 16 is closed. . When the pressure in the upper space C1 is lower than the pressure in the lower space C2, the diaphragm 12 firmly abuts against the ceiling of the valve chamber 14, as shown in FIG. , and the diaphragm 12 is separated from the valve seat 18 to open the nozzle 16 .

As a result, the pressure of the gas pressurized in the tank chamber 15 can be accumulated, and the pressure-accumulated gas can be released instantaneously.

Next, how to use the dust collection filter cleaning device 1 will be described. First, the pump P is connected to the pressurized gas introduction side of the electromagnetic three-way valve 13 . Gas uses air. In addition, although air is used as the gas in this embodiment, helium or the like may be used. As shown in FIG. 6 , the dust collection filter 23 to be cleaned is placed below the dust collection filter cleaning device 1 with the opening facing upward.

The electromagnetic three-way valve 13 is used when connecting the gas conduit 17 and the discharge side of the pump P, when closing the gas conduit 17 and the outside of the casing 11, and when opening the gas conduit 17 to the atmosphere. It is a switching valve for selecting one of the cases.

<When filling the tank chamber with air>
When the pressure in the tank chamber 15 is lower than the discharge pressure of the pump P, when the electromagnetic three-way valve 13 is operated so as to communicate the gas conduit 17 and the pump P, the pressure in the upper space C1 of the valve chamber 14 rises to the valve Since it is higher than the lower space C<b>2 of the chamber 14 , the pressure acting on the upper surface side of the diaphragm 12 exceeds the pressure acting on the lower surface side of the diaphragm 12 . Therefore, as shown in FIG. 2, the peripheral portion of the diaphragm descends to form a gap. Air supplied from the pump P flows into the tank chamber 15 through the gap between the outer peripheral edge of the diaphragm 12 and the ceiling of the valve chamber 14 . At this time, the nozzle 16 is closed.

<Accumulated pressure>
Due to the structure of the diaphragm 12, when the gas conducting path 17 and the outside of the casing 11 are closed, the pressure in the upper space C1 of the valve chamber 14 and the pressure in the tank chamber 15 are kept substantially the same. Therefore, when the pressure in the tank chamber 15 becomes equal to the discharge pressure of the pump P, the electromagnetic three-way valve 13 is operated so as to block the gas conduit 17 and the outside of the casing 11 . This is because the generated pressure wave can be maximized. In addition, in this embodiment, the discharge pressure of the pump P is 0.6 MPa.

As a result, the tank chamber 15 and the lower space C2 of the valve chamber 14 are filled with pressurized air, and the filled state is maintained. At this time, the gas conduit 17 and the upper space C1 of the valve chamber 14 are also kept filled with pressurized air. At this time, the nozzle 16 is also closed.

In this embodiment, a pressure sensor or the like for detecting whether or not the pressure in the tank chamber 15 has become the same as the discharge pressure of the pump P is not provided. It is estimated that the pressure in the tank chamber 15 has become the same as the discharge pressure of the pump P when a predetermined time has passed since the electromagnetic three-way valve 13 was operated so as to fill the tank chamber 15 with air. The electromagnetic three-way valve 13 is actuated so as to block the outside of the casing 11 from the outside of the casing 11 .

<When blowing air from the nozzle>
The electromagnetic three-way valve 13 is operated to open the gas conduit 17 to the atmosphere. As a result, the pressure in the upper space C1 of the valve chamber 14, which is always in communication with the gas conduit 17, becomes lower than the pressure in the lower space C2, so that the central portion of the diaphragm 12 is separated from the valve seat 18 as shown in FIG. The lower space C2 of the valve chamber 14 and the nozzle 16 are communicated with each other.
At this time, the upper space C<b>1 of the valve chamber 14 and the tank chamber 15 are blocked by the diaphragm 12 .
As a result, the gas pressure-accumulated in the tank chamber 15 can be released instantaneously.

The gas released from the tank chamber 15 is jetted into the dust collection filter 23 through the nozzle 16 . At this time, pressure waves are generated.
Although the details of the principle by which dust can be removed from the dust collection filter 23 have not been clarified, it is known that the dust collection filter 23 is vibrated in an extremely short period by pressure waves to shake off the dust.

(Second embodiment)
First, the configuration of the dust collector 2 will be described with reference to FIG. FIG. 6 is a cross-sectional view schematically showing the dust collector 2 of this embodiment (there are some parts that are not cross-sectional views, such as a dust filter, an electromagnetic three-way valve, and an intake fan).

The dust collector 2 is mainly composed of a dust collection casing 21 , a dust collection filter 23 , a dust collection filter cleaning device 1 and an intake fan 25 . The dust collector 2 is a device that captures fine particles (hereinafter referred to as dust) formed by agglomeration of metal vapor generated during laser processing or welding. Since the dust collector 2 itself is a well-known technique, detailed description is omitted.

The dust collection casing 21 is provided with a first partition wall 21a and a second partition wall 21b, with a filter chamber 22a at the bottom, a dust collection filter cleaning device chamber 22b in the middle, and an intake fan chamber 22c at the top. is formed.

The dust collection filter 23 is arranged in the filter chamber 22a, the dust collection filter cleaning device 1 is arranged in the dust collection filter cleaning device chamber 22b, and the intake fan 25 is arranged in the intake fan chamber 22c. The dust collection filter cleaning device chamber 22b communicates with the inside of the dust collection filter 23 at the bottom and communicates with the intake port of the intake fan 25 at the top.

The filter chamber 22a is provided with an intake port 22d for taking in air containing dust from outside the filter chamber 22a into the filter chamber 22a, and the intake fan chamber 22c is provided with an exhaust port for discharging air to the outside of the intake fan chamber 22c. 22e is provided.

Accordingly, when the intake fan 25 is operated, air containing dust enters the filter chamber 22a from the outside of the filter chamber 22a and passes through the dust collection filter 23 from the outside to the inside. At this time, the dust collection filter 23 filters the dust in the air (atmosphere) to remove the dust in the air. Therefore, the trapped dust is accumulated on the outer peripheral surface side of the dust collection filter 23 .

The dust collection filter 23 has a cylindrical core material (not shown) made of punched metal, a bellows-folded filter paper material (not shown), and the like, and has a substantially cylindrical shape. . One axial end side (lower end side in the present embodiment) of the dust collection filter 23 is blocked by a blocking body (not shown).

After that, the air from which the dust has been removed passes through the dust collection filter cleaning device chamber 22b and is sucked into the intake fan 25. As shown in FIG. Then, it is discharged from the intake fan 25 to the intake fan chamber 22c, and finally discharged to the outside of the casing 21 from the discharge port 22e.

The intake fan 25 is a well-known technology that is configured by a centrifugal fan, a scroll casing, an electric motor, and the like (not shown), so description thereof will be omitted.

The dust collection filter cleaning device 1 is arranged on the first partition wall 22d with a slight distance from the first partition wall 22d. When viewed from the side, it appears to be floating in the air. The nozzle 16 of the dust filter cleaning device 1 is arranged coaxially with the dust filter 23, but does not enter the inside of the dust filter 23, and the open end of the nozzle 16 and the dust filter are separated. away.

The dust removed by the dust collection filter cleaning device 1 is collected in a dust collection section 22f provided in the lower portion of the filter chamber 22a.

Although the present invention has been described above based on the embodiments, the above-described embodiments of the present invention are intended to facilitate understanding of the present invention, and do not limit the present invention.

That is, the present invention can be modified and improved without departing from the spirit and scope of the claims, and the present invention includes equivalents thereof.

1... Dust collection filter cleaning device (first embodiment)
2... Dust collector (second embodiment)
DESCRIPTION OF SYMBOLS 11... Casing 12... Diaphragm 13... Electromagnetic three-way valve 14... Valve chamber 15... Tank chamber 16... Nozzle 17... Gas conduit 18... Valve seat 21... Dust collecting casing 23... Dust collecting filter 25... Intake fan

Claims (2)

A dust collection filter cleaning device for cleaning a dust collection filter installed in a dust collection device, comprising a valve chamber, a tank chamber communicating with the valve chamber and filled with pressurized gas, and the valve chamber. a casing having a nozzle that communicates with the tank chamber and ejects the gas released from the tank chamber toward the dust collection filter;
a diaphragm housed in the valve chamber,
The valve chamber has a circular shape in a plan view, and the diaphragm is formed such that the central portion of the ceiling is raised, and the bottom surface is formed so as to protrude upward so as to surround the opening of the nozzle. A ring-shaped valve seat in plan view is formed on which is placed,
The tank chamber is formed in an annular shape in plan view so as to surround the valve chamber,
A gas conduction path is formed inside the casing for communicating between an opening provided in the ceiling of the valve chamber and the outside of the casing,
The diameter of the gas conduit is smaller than the diameter of the nozzle, and the opening of the gas conduit communicates with the outside of the casing for switching between charging and discharging pressurized gas to the gas conduit. is formed to a size equal to or greater than the diameter of the opening on the casing side of the electromagnetic valve attached to the side ,
The diaphragm divides the valve chamber into an upper space having the same pressure as the gas conduit and a lower space having the same pressure as the tank chamber, and when the pressure in the upper space is higher than the pressure in the lower space , the peripheral edge is lowered to allow the upper space and the tank chamber to communicate with each other to guide the introduced gas to the tank chamber, and the nozzle is closed by closely contacting the valve seat, so that the pressure in the upper space is reduced to the pressure in the lower space. A dust collection filter cleaning device, characterized in that, when the pressure is lower than the pressure, communication between the gas conduit and the tank chamber is closed and the nozzle is opened by moving away from the valve seat. A dust collector for removing dust in the atmosphere,
a dust collection filter that removes dust from the captured atmosphere;
The dust collection filter cleaning device according to claim 1, which cleans the dust collection filter;
Dust collector with.

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