JPH09113435A - Measuring apparatus for dust holding amount of bag filter - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a measuring apparatus by which the dust holding amount of a dust filter (a bag filter) can be measured automatically by a method wherein a time-dependent change in a fiter differential pressure generated between an air-to-be- filtered storage chamber and a clean air chamber is recorded, an air suction operation is stopped when the filter differential pressure becomes a prescribed value and the compressed air is spouted from a nozzle. SOLUTION: A filter body part 1 is constituted of a test-piece mounting part 3, of a clean air chamber 4, of an air-to-be-filtered storage chamber 5 and of a floating- dust generation device. First, a test piece at a dust filter 47 is set on the test-piece mounting part 3, the floating-dust generation device is operated, and the filtering operation of the air in the air-to-be-filtered storage chamber 5 is started at a constant filtration speed. Simultaneously with the start of the filtering operation, a filter differential pressure ΔP due to the filter 47 is generated, and it is always measured and recorded by a differential pressure (ΔP) measuring and recording device. Then, when the differential pressure ΔP which is increased due to an increase in a dust accumulation amount reaches a preset value, an air suction operation by an isokinetic sampling device is stopped, and dust particles which are stuck to the test piece are blown off by the compressed air.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a bag-shaped filter material used for a dust collector, a dust collector, an air transportation device, etc., and a device for testing the filtering performance of a so-called bag filter, and more particularly to a device for testing the dust holding amount The present invention relates to a device for measuring.

[0002] In this specification, the term "dust" is used to mean that it includes a granular material to be transported in an air transportation device.

[0003]

2. Description of the Related Art In dust removal by a dust collector and transportation of powder particles by an air transportation device, dust accumulated on the surface of a bag filter as time passes, the pressure difference between air before and after passing through the filter (so-called filter differential pressure). ) Δ
P gradually rises. Then, in the dust collection, the amount of suction air decreases and the dust cannot be collected, and in air transportation, dust blows through the filter or the filter is broken. Therefore, when the differential pressure ΔP reaches a certain value or after a lapse of a certain period of time, an operation is performed (in many cases automatically) to remove the accumulated dust to reduce the differential pressure ΔP.

A bag filter, in which the differential pressure ΔP hardly rises even if dust is accumulated, is advantageous because the interval for dusting-off operation can be lengthened and the power consumption for air suction can be reduced. Therefore, it is necessary to confirm the quantitative treatment capacity of the bag filter in addition to the qualitative capacity such as exhaust concentration and separation efficiency in order to design the dust collector.

In order to show the quantitative performance of the bag filter, the mass per unit area of the dust accumulated on the filter is called the dust load, and the filtration speed is changed with respect to a certain dust load, and the differential pressure ΔP corresponding thereto is changed. The measured data is displayed. In this case, since the differential pressure ΔP varies variously depending on the complicated properties of dust and the filtration wind speed, the pressure difference under the same dust, the same filtration wind speed, and the same dust load condition can be compared to compare the filter performance. When ΔP is compared, the lower ΔP means a better filter. Also, from the same data, it is determined that the filter having the same differential pressure ΔP and the larger dust load is the better filter.

However, the term dust load is more than a mere load on the filter in the art, rather than the above meaning.
It is often used in the sense of burden, and is rarely used in the sense of the quantitative capacity of bag filters. The cause is that it is difficult to measure the dust load accurately. That is, in order to obtain the dust load as a quantitative capacity, the work of measuring the mass of dust accumulated every time it is removed is continued until the dust mass becomes stable. However, it takes a lot of time and labor to collect and weigh dust, so it is often stopped after a few times. In addition, even if the measurement is performed several hundred times until the measured dust mass is stable, the dust load also changes depending on the nature of the dust, the filtration rate, etc. It is only valid below and is not universal. It simply determines the rank of superiority or inferiority.

Conventionally, the most commonly used method for evaluating the quantitative performance of a bag filter is to repeat the suction and removal of dust under the same conditions by repeating the differential pressure ΔP measured immediately after restarting the suction. It records the (base pressure loss), compares the values when the gradually increasing base pressure loss finally becomes stable and does not rise any more, and evaluates a filter having a low value as good performance.

However, this evaluation method requires only the result of the saturation value of the base pressure loss, so that it is difficult to find the cause and it is not possible to use it technically. Therefore, the evaluation result focusing on the base pressure loss is only a reference when designing a machine / apparatus using a bag filter such as a dust collector, and in practice, experience and achievements are often emphasized.

As described above, it is essentially desirable to accurately measure the dust load and use the result rather than judging the performance of the bag filter from the result of measuring the differential pressure ΔP. From this point of view, a deep study of the relationship between the dust load and the differential pressure ΔP reveals that the dust load is particularly important when the base pressure loss becomes stable by repeating dust absorption and dust removal, and it is also used in the conventional method. We find that the term dust load, which is known, was ambiguous in meaning. Therefore, the present inventor newly introduces the concept of dust holding amount by defining dust load = residual dust amount + dust holding amount, and pays attention to this dust holding amount in order to evaluate the quantitative performance of the bag filter. And

Here, dust load (g / m ² ): total dust mass deposited on the filtration surface of the filter. Residual dust amount (g / m ² ): Mass of dust remaining on the filter surface and inside even after the dust is blown off. Dust holding amount (g / m ² ): The amount of dust newly deposited on the filter until the pressure reaches a certain value after the dust is blown off, that is, the mass of dust newly filtered by the filter. It is.

By introducing the concept of the dust holding amount, the performance of the bag filter can be evaluated more accurately than before, but the device for measuring the dust holding amount is
Not surprisingly, it didn't exist before.

[0012]

SUMMARY OF THE INVENTION An object of the present invention is to provide a dust holding amount measuring device capable of automatically measuring the dust holding amount of a bag filter.

Another object of the present invention is to provide a new means for evaluating the performance of a bag filter by enabling easy measurement of the dust holding amount of the bag filter, and to provide a bag filter and dust collection and air transportation using the bag filter. To contribute to the technical improvement of.

[0014]

A dust holding amount measuring apparatus of the present invention that has succeeded in achieving the above object has a space having a space capable of temporarily storing filtered air containing test dust at a constant concentration. Filtered air storage chamber; Means for supplying and retaining filtered air containing suspended dust at a constant concentration in the filtered air storage chamber; consisting of a pair of annular members for sandwiching the bag filter test piece in a vertically arranged state A test piece mounting portion that is separably connected to the top opening of the filtered air storage chamber; integrated with an upper side of the annular member that constitutes the test piece mounting portion, and is connected to constant velocity air suction means, Also, a clean air chamber equipped with a compressed air injection nozzle for injecting compressed air for dust removal into the room; rotatably supporting a test piece mounting portion and a clean air chamber integrated with the test piece mounting part, and supporting them with the air to be filtered. Storage A test piece mounting part supporting member that can be swung 180 degrees apart from the state where it is connected to the top opening of the swivel, and can be turned upside down; Filtered air storage chamber and clean air based on air suction by constant velocity air suction means Pressure difference Δ between filter and chamber
Means for measuring P; and recording the change over time of the differential pressure ΔP, and when the differential pressure ΔP reaches a predetermined value, the air suction by the constant velocity air suction means is stopped and compressed air is jetted from the compressed air jet nozzle. A control device;

This dust holding amount measuring device is for carrying out a dust holding amount measuring method based on the following principle devised by the present inventor.

A bag filter test piece was set in a test filtration device, and suction filtration was performed at a constant filtration rate v (m / min) while keeping the dust concentration m (g / m ³ ) of the air to be filtered constant. In this case, if the filter pressure difference reaches ΔP _t by continuing the filtration for t minutes, the dust holding amount M (g / m ² ) at the pressure difference ΔP _t is expressed by the equation M = mvt. Therefore, the dust holding amount M at that time can be calculated from the elapsed time t without stopping the filtration and weighing the dust that has been shaken off (the dust concentration m and the filtration speed v are set to the initially set filtration). It is constant because it is a condition).

The filtration speed v is the linear velocity of air that is sucked and passes through the test piece, where the filtration area is S (m ² ), and the amount of suction air per unit time is Q (m ³ / min). Then v =
Q / S.

[0018]

BEST MODE FOR CARRYING OUT THE INVENTION Next, the structure of a dust holding amount measuring device according to the present invention will be described in detail with reference to the drawings with reference to specific examples.

A typical example of the measuring device according to the present invention is, as shown in FIG. 1, a main body portion 1 which is a filter and a differential pressure ΔP.
The measurement / recording device, the sequential controller, the constant velocity suction device, the compressed air supply source 2 and the like are the main parts.

The main body portion 1 is, as shown in FIGS.
Test piece attachment part 3, clean air chamber 4, filtered air storage chamber 5,
The floating dust generator 6 is a main constituent member.

The test piece mounting portion 3 includes a pair of annular members 7 and 8 for holding the test piece S, a hinge 9 for connecting the annular members 7 and 8, and a fastening metal fitting 10 for the annular members 7 and 8.
(There are 4 in total) and so on. On the upper annular member 8, a clean air chamber 4 having a space required to equalize the suction pressure acting on the test piece S and to perform an air jet for the later-described blow-off is fixed.

The clean air chamber 4 includes a rotatable exhaust pipe 1
1 and a hose (not shown) are connected to a constant velocity suction device (a vacuum pump, a turbo blower with a rotation speed control device, or the like can be used). Further, a compressed air injection nozzle 12 and a compressed air source 2 therefor are provided on the top thereof.
A connecting pipe 13 for connecting the test piece S to the test piece S mounted on the test piece mounting portion 3 is rotatably mounted.
It is possible to radially inject compressed air toward.

A pair of test piece support members 50 are further mounted inside the clean air chamber 4, which will be described later in detail.

In the measurement state shown in the drawing, the test piece mounting portion 3 and the clean air chamber 4 have a cylindrical member 15 which stands upright from the base plate 14 (an annular seat 16 having the same diameter as the annular members 7 and 8 is fixed to the tip end thereof). However, apart from this, there is a lever 19 having a support shaft 18 at the tip of the column 17 on the base plate 14 as a pivot shaft (there are the same on the rear side of FIG. It is rotatably supported by. That is, the shaft 20 protruding from the side surface of the clean air chamber 4 is loosely fitted in the hole at the intermediate position of the lever 19, and when the lever 19 is swung, the test piece mounting portion 3 and the clean air chamber 4 are separated from each other by the annular seat body. It is separated from 16, is supported only by the lever 19, and is in a rotatable state.

Lever 19 which is a support member for the test piece mounting portion
2 is capable of turning 180 degrees in the clockwise direction in FIG. 2, and when turned to the limit, the clean air chamber 4 and the test piece attachment portion 3 can be moved laterally and then turned to the inverted state. It is possible (the inverted state is shown by a chain double-dashed line in FIG. 2. Further turning of the lever 19 is blocked by the stopper 21).

The lever 19 supports the clean air chamber 4 by the above-mentioned mechanism, and the U-shaped engaging member 22 at the tip is provided with a tightening fitting 23 (a bolt 25 and a nut 26 pivotably attached to the base plate 14 by a support shaft 24). 2), the tightening metal fitting 23 in the engaged state is tightened, and when a force for pressing in the counterclockwise direction in FIG. 2 is applied to the lever 19, the clean air chamber 4 and the test are performed via the shaft 20. The one-sided mounting portion 3 can be pressed downward to be brought into close contact with the annular seat body 16.

A rubber O-ring 28 is fixed to the lower surface of the annular member 7 to keep the annular member 7 and the annular seat body 16 in an airtight state in the tightened state. Also,
The clean air chamber 4 and the cylindrical member 15 are provided with differential pressure detection tube connection ports 29 and 30. By connecting these to the differential pressure ΔP measuring / recording device with a tube, the differential pressure Δ
P can be constantly measured and recorded.

Immediately below the cylindrical member 15, there is a filtered air storage chamber 5 fixed to a frame 31 that supports the entire apparatus. The vibration of the filtered air storage chamber 5 is transmitted to the test piece mounting portion 3. In order to prevent the filtration performance of the test piece from being affected, the opening at the top of the filtered air storage chamber 5 and the cylindrical member 1
5 is not directly connected, but a short hose 32 made of a flexible material is interposed (the base plate 14 is also provided with a rubber cushioning material 33 for preventing vibration, and the filtered air storage chamber 5
It is attached to the ceiling of. ).

In the filtered air storage chamber 5, a pair of opposing walls 35 and 36 are inclined in a funnel-shaped cross section, and a floating dust generating device 6 is attached to the rectangular lower end opening. .

The details of the floating dust generator 6 will be described with reference to FIGS. 4 and 5. The screw conveyor 37 is installed in the gutter-shaped dust storage section 38, and the dust D stored in the dust storage section 38 is slightly discharged. Each of them is fed to the left in FIG. 5 to be supplied to the dust dispersion device. The screw conveyor 37 basically uses a coil spring 37a to prevent clogging of dust. Therefore, dust feeding is intermittent or close to that, but has a large number of blades in a spiral gear shape. The adjust screw 39 is mounted at a distance from the tip of the coil spring 37a, and the dust feed by the coil spring 37a portion is temporarily interrupted (or reduced) at a portion opposite to the coil spring tip A portion. The blade 39a is protruded in the direction of the portion A to increase the amount of dust taken in, thereby making it possible to supply a fixed amount of dust.

The dust disperser comprises a rotary brush 40 having a large number of synthetic resin (for example, nylon) bristles and metal wires radially implanted, a casing 41 formed so as to be in contact with substantially the lower half thereof, and a rotary brush. Just above 40,
The partition plate 55 is installed parallel to the axis of the rotating brush 40 so as to divide the inside of the casing 41 into two parts. The rotating brush 40 is rotated by the motor M, and the dust D is dropped from the tip of the screw conveyor 37 into the portion (the right half portion in FIG. 4) where the peripheral surface of the rotating rotating brush 40 enters the casing 41, and becomes the dust D. A strong shearing force is applied to crush aggregated particles, and the crushed dust is scattered upward from the opposite side. Further, an air nozzle 42 for blowing compressed air in the tangential direction of the peripheral portion of the rotary brush 40 is opened immediately below the dust dropping portion of the casing 41 as needed.

Casing 41 partitioned by a partition plate 55
The inner space is a flat wall formed by a partition wall 56 standing in the filtered air storage chamber 5 as an extension of the casing wall between the rotary brush 40 and the motor M and a vertical wall 57 of the filtered air storage chamber 5. The space communicates with the space inside the filtered air storage chamber 5, and the flat space is also divided into two parts by a partition plate 55 a which is an extension of the partition plate 55.

At one corner of the ceiling portion of the filtered air storage chamber 5 (side of the position where the cylindrical member 15 is fixed; rear side in FIG. 2), there is a passage with a dust filter, which is schematically shown in FIG. Pores 45 are provided. That is, there is a dust filter (bug filter) 47 having a large filtration area in the filter mounting chamber 46 whose bottom is opened toward the filtered air storage chamber 5, and the outer surface of the dust filter 47 is the filtered air storage chamber. In contact with the air to be filtered in the chamber 5, the inside communicates with the outside air via the exhaust fan 48 and the ventilation hole 45. There is no shutter in the ventilation path. The exhaust fan 48 is provided to prevent dust from scattering by operating when the test dust is put into the dust reservoir 38, and is not essential to the device of the present invention.

Next, a method of using this device will be described. First, the test piece S of the bag filter is set on the test piece mounting portion 3. In that case, from the measurement state shown by the solid line in FIG.
And the lever 19 is turned 180 degrees clockwise. The clean air chamber 4 rotatably supported by the lever 19 and the test piece mounting portion 3 integrated with the clean air chamber 4 are turned upside down, so that the test piece mounting portion 3 is in a state shown by a chain line pointing upward. In this state, the tightening of the annular members 7, 8 by the tightening metal fitting 10 is released, and the annular member 7 is swung (in the direction toward the back of the paper in FIG. 2) by using the hinge 9,
The annular member 7-8 of the test piece attachment portion 3 is opened. Next, the test piece S cut into a size suitable for being sandwiched by the annular members 7 and 8 is placed on the annular member 8, the annular member 7 is returned to the original position, and the tightening fitting 10 is tightened. The test piece S is hermetically sandwiched between the eight.

During the test piece mounting operation performed by reversing the clean air chamber 4 as described above, the tip 50a of the test piece support member 50 that swivels to the position shown by the chain line in FIG. The test piece S is supported by supporting the vicinity of the portion to prevent the test piece S from loosening. (The test piece supporting member 50 and its supporting mechanism will be described with reference to FIG. 6 as well. This member is made of a steel wire bent into a substantially T shape. And is fixed to the balance weight 51 made of a steel plate which is heavier than that in the leg portion 50b.
The balance weight 51 is attached to the tip of the support column 52 standing from the wall of the clean air chamber 4 toward the center of the clean air chamber 4, and the support shaft 5 is attached.
It is supported by 3 so as to be rotatable in a vertical plane. The test piece support member 50 is fixed to the balance weight 51 in such an arrangement that the linear tip portion 50a thereof is orthogonal to the plane including the balance weight 51.
Even if the balance weight 51 rotates, the tip 50a is always parallel to the test piece S. Balance weight 51
Rotates due to the rotation moment generated when the support position O by the support shaft 53 is separated from the center of gravity G,
The rotating direction is reversed depending on the posture of the clean air chamber 4, and the rotatable range is limited by the a portion or the b portion contacting the wall surface of the clean air chamber 4. When the test piece is mounted with the clean air chamber 4 inverted, the above-mentioned rotational moment causes the balance weight 51 to rotate in the direction in which the portion a of the balance weight abuts against the wall surface of the clean air chamber 4, and the state is maintained even after the abutment. Let In that state, the balance weight 51 becomes the test piece support member 50.
Is held at a position indicated by a chain line where its tip 50a is almost in contact with the test piece S to prevent the test piece to be attached from being loosened. At the time of measurement when the clean air chamber 4 is in the upright state as shown in FIG. 3, the balance weight 51 rotates in the direction in which the portion b contacts the wall surface of the clean air chamber 4, and the tip 50a is sufficiently separated from the test piece S. It does not affect the filtration test because it is in the open position. It goes without saying that the shapes and materials of the test piece support member and the balance weight can be arbitrarily changed within the range in which the automatic test piece support and the withdrawal as described above are possible. ).

On the other hand, an appropriate amount of dust D (standard powder for testing) is put in the dust storage section 38 (a part of the dust needs to remain in the storage section 38 even during the suction cycle of the filtration test described later). is there.).

Then, the lever 19 is rotated to move the lever 19
And the test piece attachment part 3 is returned to the original position. When the tightening fitting 23 is tightened, the annular member 7 of the test piece mounting portion 3
8 comes into close contact with the annular seat body 16 and becomes in the measurable state of FIG.

After that, when the constant velocity suction device and the suspended dust generating device 6 are operated, the filtration of the air in the filtered air storage chamber 5 starts at a constant filtration speed v (m / min). In the floating dust generator 6, the dust D supplied in a fixed amount by the screw conveyor 37 is caught in the rotation of the rotating brush 40,
The agglomerated particles are crushed by a strong shearing force, and then scattered upward at a high speed. At this time, the rotating brush 40 rotating in the clockwise direction in FIG. 4 acts as a blower, and the casing 41 passes from the filtered air storage chamber 5 via the duct-shaped portion 58.
Since the airflow that enters inside and is discharged to the duct-shaped portion 59 is generated, the crushed dust rides on this airflow to rise in the duct-shaped portion 59 and is discharged to the upper space of the filtered air storage chamber 5. . In this way, the air flow generated by the rotating brush 40 conveys the dust into the filtered air storage chamber 5 and at the same time agitates the air in the chamber to homogenize the dust concentration. The air injection from the air nozzle 42 helps to disperse the dust due to the rotation of the rotary brush 40 and to reduce the load of the rotary brush 40 driving motor M when the dust amount is large.

Even when air is not jetted from the air nozzle 42 attached to the dust dispersing device, or even when air is jetted from the air nozzle 42, the amount of jetted air per unit time is smaller than the amount of air sucked through the test piece S. At this time, the supply of air to the filtered air storage chamber 5 is automatically performed by the outside air of the device flowing from the ventilation hole 45 through the dust filter 47 into the filtered air storage chamber 5 having a slightly negative pressure. Be seen. At this time, if the ventilation resistance of the dust filter 47 is large, it affects the measured value of the differential pressure ΔP, so the filtration area of the dust filter 47 is made sufficiently larger than that of the test piece S.

When a larger amount of air than the amount of air sucked through the test piece S is jetted from the air nozzle 42,
Excess air in the filtered air storage chamber 5 causes dust filter 47
The air is discharged from the ventilation hole 45 to the outside of the device via the air vent, and the pressure in the room is prevented (the exhaust fan 48 is not operated). At this time, the dust contained in the released air is collected by the dust filter 47.

As described above, the inside of the filtered air storage chamber 5 is maintained at about atmospheric pressure during the test, and the dust concentration m (g / g / g
m ³ ) is kept constant. However, even if the dust concentration in the filtered air storage chamber 5 in which the dust circulates as described above is constant on average, there may be some concentration unevenness depending on the location.
However, this concentration unevenness is also eliminated while the air to be filtered slowly rises in the cylindrical portion composed of the hose 32 and the cylindrical member 15 and reaches the test piece. That is, the cylindrical portion also serves as an adjusting space for making the dust concentration of the filtered air uniform and rectifying the air flow only toward the test piece.

A filter differential pressure ΔP is generated at the same time as the start of filtration.
A differential pressure ΔP measuring / recording device connected to 0 is constantly measured and recorded. Differential pressure Δ that increases as the amount of accumulated dust increases
P is a preset value (eg 150 mmH ₂ O)
When the value reaches, the air suction by the constant velocity suction device is stopped, and the screw conveyor 37 and the rotating brush 40 are also stopped. Next, compressed air is jetted from the compressed air jet nozzle 12 toward the test piece S for a short time to give a shock to the test piece S, and the adhered dust is blown off.

The dust blown off from the test piece S during the dust blow-off process is partly directly, and most of the dust is the filtered air storage chamber 5.
After colliding with the side walls 35 and 36 having a funnel-shaped cross section, it falls to the dust storing section 38 and is reused for preparing the air to be filtered. Further, when the amount of dust on the dust filter 47 increases, the vibration imparting device 53 vibrates the filter to remove the adhered dust during the suspension period of filtration (the dust thus removed is also the dust storage unit). 38). As a result, all the test dust except the one leaking from the test piece S circulates in the apparatus.

The above-mentioned filtration-suspension of filtration-shuffling is automatically repeated by a sequential controller for a sufficient number of cycles (usually several hundreds) to stabilize the base pressure loss. FIG. 7 is a time chart of an example thereof.

Using the above equation M = mvt, the test piece S
The dust holding amount M in each cycle can be obtained with the device set in the apparatus, and its change over time can be known. The dust concentration m at this time can be measured by the following method. First, after only the filtration in the first (or any of the initial) cycles is completed, the operation of all the devices is stopped without performing the compressed air injection for blow-off, and the air is sucked by the constant velocity suction device. The test piece mounting portion 3 is turned over in the same manner as when mounting the test piece. The accumulated dust on the test piece is kept attracted to the test piece by air suction, so it does not come off due to the reversing operation. After the reversal state, since the dust adhering surface faces upward and there is no possibility of dust falling off, the air suction is stopped and the test piece S is removed from the test piece mounting portion 3. The mass of the removed test piece S with dust is measured, and the dust load is obtained as a difference from the mass of the test piece S itself.

Then, the test piece S with dust is attached to the test piece mounting portion 3 again, the test piece mounting portion 3 is returned to the measurement state, and then compressed air is jetted from the jet nozzle 12 to remove the attached dust. . For the test piece S that has been removed (preferably, for the test piece S that has been filtered and blown off until the differential pressure ΔP reaches the set value), the test piece attachment part is the same as in the case of measuring the dust load. Remove from 3 and perform mass measurement to obtain the amount of residual dust. The dust holding amount M is obtained as the difference between the dust load measured as described above and the residual dust amount, and the dust concentration m is obtained using the relational expression of m = M / vt.

Even when it is necessary to actually measure the amount of dust accumulated or observe the adhered state after repeating filtration-stopping filtration-shuffling until the base pressure loss becomes stable,
In the same manner as above, the test piece S can be removed with the dust adhering thereto, and necessary observation and measurement can be performed.

[0048]

As described above, according to the present invention, it becomes possible to automatically measure the dust retention amount of the bag filter, and it is easy to measure the performance value other than the dust retention amount and observe the dust adhesion state. Therefore, it becomes possible to more rationally design the bag filter and the dust collecting device and the air transportation device using the bag filter.

Further, it is important to keep the dust concentration constant during the measurement in the filtration test device, but in the device of the above-mentioned embodiment, a dust dispersion device integrated with the air storage chamber to be filtered is provided to A ventilation hole with a dust filter was provided in the air storage chamber to continuously generate filtered air containing dust at a constant concentration, so that technically difficult dust concentration stabilization was achieved. Not only that, it has the advantage that expensive filtration test powder is completely recycled in the equipment.

Further, the structure in which the test piece support member is provided in the clean air chamber enables the test piece to be attached without slack even when the test piece is soft, and the test piece attachment portion (and hence the test piece) has a large diameter. Therefore, it is possible to perform a highly accurate test.

[Brief description of the drawings]

FIG. 1 is an explanatory diagram showing an outline of the configuration of a measuring apparatus according to the present invention.

FIG. 2 is a front view showing a main body portion 1 of the measuring apparatus of FIG.

3 is a partially cutaway left side view showing an upper half portion of a main body portion 1 of FIG. 1. FIG.

FIG. 4 is a partially cutaway front view of the floating dust generator 6 of the main body portion 1 of FIG.

5 is a partially cutaway right side view of the floating dust generator 6. FIG.

6 shows the test piece support member 50 and balance weight 51 of FIG. 3, FIG. 6A being a view seen from the same direction as FIG.
Figure B is a left side view thereof.

7 is a time chart of an example of a filtration test by the measuring device of FIG.

[Explanation of symbols]

 1: Main body part 2: Compressed air supply source 3: Test piece mounting part 4: Clean air chamber 5: Filtered air storage chamber 6: Floating dust generator 7,8: Annular member 12: Compressed air injection nozzle 19: Lever ( 29,30: Tube connection port for differential pressure detection 37: Screw conveyor 38: Dust storage 39: Adjust screw 40: Rotating brush 45: Vent 47: Dust filter 50: Test piece support 51 : Balance weight S: Test piece

[Procedure amendment]

[Submission date] December 1, 1995

[Procedure amendment 1]

[Document name to be amended] Drawing

[Correction target item name] Fig. 5

[Correction method] Change

[Correction contents]

[Figure 5]

Claims (3)

[Claims] 1. A filtered air storage chamber having a space capable of temporarily storing filtered air containing test dust at a fixed concentration; filtered air containing chamber containing suspended dust at a fixed concentration. Means for supplying and accumulating in the above; a test piece attachment part which is composed of a pair of annular members for sandwiching the bag filter test piece in a state of being vertically arranged, and is separably connected to the top opening part of the filtered air storage chamber; A clean air chamber that is integrated with the upper side of the annular member that constitutes the test piece mounting portion, is connected to a constant velocity air suction means, and is equipped with a compressed air injection nozzle that injects compressed air for dust removal into the room. A test piece mounting portion and a clean air chamber integral therewith can be rotatably supported, and they can be turned 180 degrees apart from the state in which they are connected to the top opening of the filtered air storage chamber to be turned to an inverted state. , Turn Rotatable test piece mounting part support member;
Means for measuring the filter pressure difference ΔP generated between the filtered air storage chamber and the clean air chamber based on the air suction by the constant velocity air suction means; and the change over time of the pressure difference ΔP is recorded so that the pressure difference ΔP is A dust filter amount measuring device for a bag filter, comprising: a control device for stopping air suction by a constant velocity air suction means when a predetermined value is reached and injecting compressed air from a compressed air injecting nozzle. 2. A filtered air storage chamber having a space capable of temporarily storing air to be filtered containing test dust at a constant concentration and having a ventilation hole with a dust filter; continuous and quantitative determination of suspended dust. Floating dust generating device connected to the bottom opening of the filtered air storage chamber that is generated and supplied to the filtered air storage chamber; a pair of annular members that sandwich the bag filter test pieces in a state of being vertically arranged And a test piece mounting portion separably connected to the top opening of the filtered air storage chamber; integrated with an upper part of an annular member constituting the test piece mounting portion and connected to a constant velocity air suction means. And a clean air chamber equipped with a compressed air injection nozzle for injecting compressed air for dust removal into the room; rotatably supporting the test piece mounting portion and the clean air chamber integrated therewith, and supporting them. The top of the filtered air storage chamber Swivelable test piece mounting part support member that can be separated from the state in which it is connected to the opening part and swiveled 180 degrees to be in an inverted state; filtered air storage chamber and clean air chamber based on air suction by constant velocity air suction means Means for measuring the filter pressure difference ΔP occurring between
A control device for recording the time-dependent change of the differential pressure ΔP and stopping the air suction by the constant velocity air suction means when the differential pressure ΔP reaches a predetermined value and injecting compressed air from the compressed air injecting nozzle. Dust retention measuring device of the characteristic bag filter. 3. The clean air chamber automatically approaches the vicinity of a central portion of a test piece attached when the clean air chamber is placed in an inverted state to support the test piece, and the clean air chamber is in an upright state. 3. A test piece support member that can be retracted to a position away from the test piece during measurement in 1).
The device for measuring the amount of dust retained according to.