JP7694409B2 - Dust solidification system and dust solidification method - Google Patents

Description

The present invention relates to a dust solidification system and a dust solidification method.

Fumes generated during laser processing, plasma processing, welding, and other processes for metal materials can pose serious health risks if inhaled by workers.
Therefore, in order to keep the working environment clean, a dust collector is operated to remove dust from the working environment.
The dust collected in the dust collector has a low bulk density and is difficult to handle in this state. Therefore, the dust is compressed, solidified, and processed into an easier-to-handle state (e.g., pellets).
Once the dust has been processed into an easier-to-handle state, it can be reused by undergoing processes such as remelting.

Patent Document 1, an example of conventional technology, discloses a technology in which dust collected by a dust collector is compressed and solidified in a pre-dust box.

JP 2000-140799 A

However, there is room for improvement in the moldability of dust, including cutting chips and particles.
The present invention has been made in view of the above, and has an object to improve the moldability of collected dust.

One aspect of the present invention for solving the above problems and achieving the object is a dust solidification system for solidifying dust that includes fumes and solidification inhibitors that are larger in mass and size than the fumes.
This dust solidification system comprises a pre-duster that sucks in dust using negative pressure generated by a negative pressure source, removes solidification inhibitors from the sucked dust, and causes the dust with a reduced content of solidification inhibitors to flow in the direction of the negative pressure source, a dust capture mechanism that captures and drops the dust flowing from the pre-duster due to the negative pressure, a storage tank that stores the dust captured and dropped by the dust capture mechanism, and a dust solidification mechanism that solidifies the dust in a molding chamber.
This dust solidification system further comprises at least one of the following mechanisms (1) to (3).
(1) A dust re-entrainment prevention mechanism that prevents dust that falls from the dust capture mechanism from being re-entrained.
(2) A stirring mechanism for stirring the dust fed into the dust solidification mechanism.
(3) An air vent mechanism that prevents air from entering the molding chamber by removing air that flows into the storage tank due to negative pressure from the dust solidification mechanism.

According to the dust solidification system having the above-mentioned configuration, the content of solidification-inhibiting substances that inhibit solidification can be relatively reduced by removing the solidification-inhibiting substances that inhibit solidification using the pre-duster.
As a result, the moldability of the dust is improved.

In one aspect of the present invention, the dust re-entrainment prevention mechanism comprises a plurality of re-entrainment prevention units arranged adjacent to each other in a direction crossing the direction in which dust falls from the dust capture mechanism, and each of the plurality of re-entrainment prevention units is formed by joining a pair of plates in a mountain shape in side view, with the ridge portion formed by joining the pair of plates facing the dust capture mechanism above, and a slit is provided along the lower end of the plate to allow dust to pass downward.
When the dust is stirred by the stirring mechanism, the dust that tends to re-scatter can be prevented from scattering upward within the device.

In one aspect of the present invention, the dust re-entrainment prevention mechanism further comprises an inclined side wall on the outside of a plate body provided on a re-entrainment prevention unit located at the outermost position among the multiple re-entrainment prevention units, and slits are provided between the lower ends of the plate bodies provided on adjacent re-entrainment prevention units and between the re-entrainment prevention unit located at the outermost position and the inclined side wall.
Dust falling from the outermost part can pass downward through the slits.

In one aspect of the present invention, the dust re-entrainment prevention mechanism comprises an upper tier re-entrainment prevention unit group and a lower tier re-entrainment prevention unit group formed by a plurality of re-entrainment prevention units, and the ridge portion of each re-entrainment prevention unit in the lower tier re-entrainment prevention unit group is positioned within a slit formed in the upper tier re-entrainment prevention unit group when viewed in a plane.
It is possible to suppress dust from being re-scattered upward from the stirring mechanism.

Another aspect of the present invention is a method for solidifying dust.
The dust solidification method includes sucking dust with negative pressure generated by a negative pressure source, removing solidification inhibitors from the sucked dust, causing the dust with a reduced content of solidification inhibitors to flow toward the negative pressure source, capturing the flowing dust due to the negative pressure and causing it to fall, storing the captured and falling dust in a storage tank, and solidifying the dust in a molding chamber by a dust solidification mechanism.
The dust solidification system further includes at least one of the following (1) to (3).
(1) The falling dust is prevented from being re-scattered by a dust re-scattering prevention mechanism.
(2) Agitating the dust fed into the dust solidification mechanism.
(3) Preventing air from entering the molding chamber by removing the air that flows into the storage tank due to negative pressure from the dust solidification mechanism.

According to the above dust solidification method, the content of solidification inhibitors can be relatively reduced by the pre-duster, which improves moldability when the dust is solidified in the molding chamber.

The present invention has the effect of improving the moldability of collected dust.

FIG. 1 is a diagram showing a schematic configuration of a dust solidification system according to the present embodiment. FIG. 2 is a diagram showing the preduster of FIG. FIG. 3 is a diagram showing the dust capturing mechanism, the dust re-scattering prevention mechanism, and the storage tank shown in FIG. FIG. 4 is an enlarged view of a part of the dust re-scattering prevention mechanism shown in FIG. FIG. 5 is a diagram showing the stirring mechanism and the dust solidifying mechanism of FIG. FIG. 6 is a diagram showing the stirring mechanism, the dust solidifying mechanism, and the air vent mechanism of FIG.

An example of the dust solidification system of the present invention will be described with reference to the drawings.
However, the present invention should not be construed as being limited to the following embodiments.

<Embodiment>
In the following description, the case of solidifying dust generated from a laser processing machine will be described as an example.
This dust contains fine fumes and coarse spatters.
Fumes are easily compressed and solidified.
Spatter has a larger mass and size than fumes and is less likely to solidify.
Spatters are an example of a solidification inhibitor that impairs moldability when the dust is solidified into pellets.
Therefore, when the generated dust (containing fine fumes and coarse spatters) is solidified, it is necessary to increase the content of fine fumes.

FIG. 1 is a diagram showing a schematic configuration of a dust solidification system 1 according to the present embodiment.
The dust solidification system 1 shown in FIG. 1 includes a pre-duster 2 that classifies sucked dust and removes solidification inhibitors, and a dust collector 3 that includes each of the components within a housing.
The dust collector 3 includes a dust capturing mechanism 31 , a dust re-scattering prevention mechanism 32 , a storage tank 33 , a stirring mechanism 34 , a dust solidification mechanism 35 , and an air vent mechanism 36 .
The dust solidification system 1 collects dust.

FIG. 2 is a diagram showing the preduster 2 of FIG.
The pre-duster 2 is installed on the side of the dust collector 3 and includes a dust inlet 21 that sucks in and introduces dust from an external dust source, and a classification section 22 that classifies the dust introduced from the dust inlet 21 and removes any substances that hinder solidification.

A duct (not shown) extending to a dust source is connected to the dust inlet 21 , and the dust inlet 21 sucks in dust by negative pressure generated by a negative pressure generating source of the dust collector 3 .
The classifier 22 removes solidification-inhibiting substances from the sucked dust to reduce the content of solidification-inhibiting substances, and causes the dust with the reduced content of solidification-inhibiting substances to flow to the dust collector 3.
The movement of dust in the preduster 2 is achieved by a negative pressure suction force generated by driving a negative pressure generating source provided in the dust capturing mechanism 31 in the dust collector 3 .

If the dust introduced into the dust collector 3 contains a high content of spatters, the moldability of the dust when it is solidified into pellets in the dust collector 3 decreases.
Therefore, the pre-duster 2 separates the fumes and spatters in the sucked dust, thereby reducing the spatter content in the dust to a predetermined ratio (or less), and then flows the dust into the dust collector 3.
This reduces the spatter content in the dust introduced into the dust collector 3, and improves the moldability when the dust is solidified into pellets in the dust collector 3.
Furthermore, the pre-duster 2 also removes steel plates or the like that are erroneously sucked up and are several millimeters or larger in size.
Therefore, the pre-duster 2 can prevent the intrusion of erroneously sucked-up objects into the dust collector 3, and can prevent abnormal stoppage and damage to the dust collector 3 due to erroneously sucked-up objects getting caught when solidifying dust in the dust collector 3.

For example, when the dust sucked into the dust inlet 21 is 50% sputter and 50% fumes, the dust flowing into the dust collector 3 can be 20% sputter and 80% fumes with the Preduster 2.

The solidification inhibitor recovery section 23 is located below the classification section 22 and recovers solidification inhibitors such as spatter that have been removed by the classification section 22 and fallen.

FIG. 3 is a diagram showing the dust capturing mechanism 31, the dust re-scattering prevention mechanism 32, and the storage tank 33 of FIG.
The dust capturing mechanism 31 is provided on the upper part of the dust collector 3 and captures the dust flowing from the pre-duster 2 and drops it.

The dust capture mechanism 31 comprises a fan 311 which is a negative pressure generating source that generates negative pressure at the top of the dust collector 3, a filter 312 which captures the dust introduced from the pre-duster 2, and a dust brushing mechanism (not shown) which scrapes off dust adhering to the filter 312.
The dust adhering to the filter 312 is scraped off by a dust-brushing mechanism (not shown), and the dust detached from the filter 312 falls by its own weight.
If the dust adhering to the filter 312 is peeled off by its own weight over time, it is not necessary to provide a dust brushing-off mechanism.
Here, dust adhering to the filter 312 is periodically brushed off while the fan 311 is in operation.
However, dust adhering to the filter 312 may be brushed off even when the fan 311 is stopped.

FIG. 4 is an enlarged view of a part of the dust re-scattering prevention mechanism 32 shown in FIG.
If the dust adhering to the filter 312 is scraped off while the fan 311 is operating as described above, the fumes, which are relatively light, are stirred up by the air current from below generated by the fan 311 and scattered again.
The dust re-scattering prevention mechanism 32 blocks the airflow from below, thereby preventing the dust that falls from the dust capture mechanism 31 from being re-scattered upward and flowing backward.
The dust re-entrainment prevention mechanism 32 may be omitted if there is no backflow due to re-entrainment of dust or if the effect is small.

The dust re-entrainment prevention mechanism 32 includes an inclined side wall 320 and a plurality of re-entrainment prevention units 321 .
The re-entrainment prevention units 321 are disposed adjacent to each other in a direction transverse to the direction in which the dust falls from the dust capture mechanism 31 .
The re-scattering prevention unit 321 is configured by joining a pair of plate bodies P1, P2 extending in the depth direction in Figure 4 so as to form a gable shape, i.e., a mountain shape when viewed from the side, and forming an apex T that constitutes the ridge line.
The ridges formed by joining the pair of plate bodies P1, P2 are disposed substantially parallel to each other and facing the dust capturing mechanism 31 above.
A slit S for allowing dust to pass downward is provided along the lower ends of the pair of plates P1, P2.
The width of the slit S may be, for example, 15 mm to 20 mm, but the present invention is not limited to this.

In addition, it is preferable that the dust re-entrainment prevention mechanism 32 further includes an inclined side wall 320 shown in Figure 3 on the outside of the plate bodies P1, P2 provided on the re-entrainment prevention unit 321 located at the outermost position among the multiple re-entrainment prevention units 321.
In the upper re-entrainment prevention unit group 32U, it is preferable that the slits S are formed not only between the lower ends of the plate bodies P1, P2 of adjacent re-entrainment prevention units 321, but also between the re-entrainment prevention unit 321 located at the outermost edge and the inclined side wall 320.

In addition, it is preferable that the dust re-entrainment prevention mechanism 32 includes an upper re-entrainment prevention unit group 32U and a lower re-entrainment prevention unit group 32L formed by a plurality of re-entrainment prevention units 321.
Furthermore, it is preferable that the apex T constituting the ridge portion of each re-entrainment prevention unit 321 of the lower re-entrainment prevention unit group 32L is positioned within a slit S formed in the upper re-entrainment prevention unit group 32U when viewed in a plane.

The storage tank 33 shown in FIG. 3 has an inclined side wall 330 and stores the dust that has passed through the dust re-entrainment prevention mechanism 32 .
In addition, when the dust re-scattering prevention mechanism 32 is omitted, the storage tank 33 may be configured to collect the dust that has fallen from the dust capture mechanism 31.

In addition, in the lower re-entrainment prevention unit group 32L, it is preferable that slits S are also formed between the multiple re-entrainment prevention units 321 and the inclined side wall 330 of the storage tank 33, similar to the upper re-entrainment prevention unit group 32U.

FIG. 5 is a diagram showing the stirring mechanism 34 and the dust solidifying mechanism 35 of FIG.
The stirring mechanism 34 shown in FIG. 5 is disposed below the storage tank 33 .
The content of fumes and spatters in the dust stored in the storage tank 33 may vary depending on the operating state of the dust solidification system 1 and the re-scattering of the dust.
The stirring mechanism 34 includes a stirring arm 340, and stirs and homogenizes the dust stored below the storage tank 33 by rotating the stirring arm 340 or the like.
The dust homogenized by stirring is transferred to the dust solidification mechanism 35 .
The stirring mechanism 34 has a simple structure and can homogenize the components of the dust, thereby stably solidifying the dust.

In addition, if the dust can be sufficiently solidified, such as when solidification inhibitors have been sufficiently removed by the pre-duster 2, the stirring mechanism 34 may be omitted.

FIG. 6 is a diagram showing the stirring mechanism 34, the dust solidifying mechanism 35, and the air vent mechanism 36 of FIG.
The dust solidification mechanism 35 shown in FIG. 6 is disposed at a position where the dust stirred by the stirring mechanism 34 is stored.
The dust solidification mechanism 35 solidifies the dust homogenized by the stirring mechanism 34 into pellets in the molding chamber 350 .

The dust solidification mechanism 35 includes a forming member 352 disposed in a forming chamber 350 and provided with a forming hole 351 , rods 353 and 354 , and a discharge hole 355 .
The rod 354 is a pressure rod that can advance into and retreat from the forming hole 351 .
The rod 353 is a closing rod, which is a stationary rod during molding of the solidified material.
Rod 353 pushes the homogenized dust in molding chamber 350 into molding hole 351, and within molding chamber 350, the homogenized dust is compressed by the pressure surfaces of rod 353 and rod 354 to form a pellet-shaped solidified material.
The formed solidified material is sandwiched between rods 353 and 354, passes through forming hole 351 together with rods 353 and 354, and is transported to discharge hole 355 and discharged.

Here, it has been described that rod 354 is a pressure rod and rod 353 is a closing rod, but the present invention is not limited to this. Rod 354 may be a closing rod and rod 353 may be a pressure rod, or both rods 353 and 354 may be capable of reciprocating motion.
The cross-sectional shape of the rods 353 and 354 may be circular or may be polygonal, such as a regular hexagon.

The air vent mechanism 36 removes air that flows into the storage tank 33 from the dust solidification mechanism 35 due to negative pressure, thereby preventing air from entering the molding chamber 350 and preventing dust from scattering in the molding chamber 350 of the dust solidification mechanism 35.
Furthermore, when dust scatters, fumes, which are relatively light, scatter preferentially. However, by preventing dust from scattering, the content of solidification inhibitors in the molded solidified product can be reduced.

The air vent mechanism 36 includes an air vent hole 360 , an air vent duct 361 , a seal portion 362 , and a partition wall 363 .
The ventilation hole 360 is provided outside the molding chamber 350 and on the path of the rods 353 and 354 .
The air vent duct 361 communicates with the ventilation hole 360 at its inside, and forms an evacuation path for the air that has flowed in from the paths of the rods 353 and 354 .
The seal portion 362 is a member that simply seals between the molding chamber 350 and the ventilation hole 360 .
The partition wall 363 is a member that surrounds the air vent duct 361 and ensures a path for the air vent duct 361 .

If there is no dust scattering in the molding chamber 350 or the effect is minimal, the air vent mechanism 36 may be omitted.

Next, the operation of the dust solidification system 1 will be described.
The operation of the fan 311 generates a negative pressure, and the dust is sucked into the preduster 2 by this negative pressure.
The sucked dust is classified by the pre-duster 2, and spatters and the like that hinder solidification are removed.

The removed spatters and the like are collected in a solidification inhibitor collection section 23 provided below the preduster 2 .
The remaining dust is transferred from the pre-duster 2 to the dust collector 3 by negative pressure.

The transported dust adheres to the filter 312 .
The adhering dust is scraped off by a dust brushing mechanism (not shown) and falls below the dust collector 3.
Dust falling below the dust collector 3 slides down the upper re-entrainment prevention unit group 32U, the lower re-entrainment prevention unit group 32L, and the inclined side wall 320 of the dust re-entrainment prevention mechanism 32, passes through the slits S at the bottom of each, and is stored in the storage tank 33 located below the dust re-entrainment prevention mechanism 32.

The dust stored in the storage tank 33 is intermittently fed into the stirring mechanism 34 located below the storage tank 33, where it is stirred to make the fumes and spatter homogenous.

The stirred dust is fed into the molding chamber 350 of the dust solidification mechanism 35 .
The dust fed into the molding chamber 350 is compressed by rods 353 and 354 and molded into a pellet-like solid.
At this time, the air inside the molding chamber 350 is removed by the air removal mechanism 36 .
The extracted air is exhausted to the storage tank 33 via the ventilation hole 360 and the air extraction duct 361, etc.

The pelletized dust is discharged through the discharge hole 355.

As described above, according to each configuration of the dust solidification system 1 according to this embodiment, the following effects can be obtained.
The pre-duster 2 can reduce the content of spatter, which is a solidification inhibitor, in the dust.
The dust capturing mechanism 31 allows dust to be introduced into the dust collector 3 and dropped there.
The dust re-entrainment prevention mechanism 32 makes it possible to send the dust to the storage tank 33 while preventing the dust from flowing back due to re-entrainment.
A stirring mechanism 34 allows homogenization of the dust below the storage tank 33 .
The homogenized dust can be solidified by the dust solidification mechanism 35 .
The air vent mechanism 36 can prevent air from entering the molding chamber 350 of the dust solidification mechanism 35, thereby preventing dust from scattering in the molding chamber 350 and suppressing the content of solidification inhibitors in the solidified material.
Therefore, according to the dust solidification system 1 of this embodiment, the collected dust can be solidified with high moldability.
Furthermore, according to this embodiment, all processes from dust collection to dust solidification can be carried out continuously in one system.

In this embodiment, a dust solidification system including a pre-duster 2, a dust capture mechanism 31, a dust solidification mechanism 35, a dust re-scattering prevention mechanism 32, a storage tank 33, a stirring mechanism 34, and an air vent mechanism 36 has been described, but the present invention is not limited to this.
The dust re-scattering prevention mechanism 32, the stirring mechanism 34, and the air vent mechanism 36 may be omitted as necessary, and it is sufficient that at least one of them is provided.

In the present embodiment, the case where dust generated from a laser processing machine is solidified has been described as an example, but the present invention is not limited to this.
The present invention can be applied to dust that contains factors that inhibit solidification, such as dust that is generated during processing with a plasma processing machine or during welding.

LIST OF SYMBOLS 1 Dust solidification system 2 Pre-duster 21 Dust inlet 22 Classifier 23 Solidification-inhibiting material recovery section 3 Dust collector 31 Dust capture mechanism 311 Fan 312 Filter 32 Dust re-entrainment prevention mechanism 32U Upper re-entrainment prevention unit group 32L Lower re-entrainment prevention unit group 320 Inclined side wall 321 Re-entrainment prevention unit T Top P1, P2 Plate body S Slit 33 Storage tank 330 Inclined side wall 34 Stirring mechanism 340 Stirring arm 35 Dust solidification mechanism 350 Forming chamber 351 Forming hole 352 Forming member 353, 354 Rod 355 Discharge hole 36 Air vent mechanism 360 Ventilation hole 361 Air vent duct 362 Sealing section 363 bulkhead

Claims (4)

A dust solidification system for solidifying dust containing fumes and solidification inhibitors having a mass and size larger than those of the fumes, comprising:
a pre-duster that sucks dust by a negative pressure generated by a negative pressure generating source, removes solidification-inhibiting substances from the sucked dust, and causes the dust with a reduced content of the solidification-inhibiting substances to flow in a direction toward the negative pressure generating source;
a dust capturing mechanism for capturing and dropping dust flowing from the pre-duster due to the negative pressure;
a storage tank for storing dust captured by the dust capturing mechanism and falling;
a dust solidification mechanism for solidifying the dust in the molding chamber;
and
a dust re-scattering prevention mechanism that prevents the dust that falls from the dust capturing mechanism from being re-scattered;
a stirring mechanism for stirring the dust fed into the dust solidification mechanism;
an air vent mechanism that prevents air from entering the molding chamber by venting air that flows into the storage tank due to the negative pressure from the dust solidification mechanism;
At least one of the following :
The dust re-entrainment prevention mechanism includes a plurality of re-entrainment prevention units arranged adjacent to each other in a direction crossing the falling direction of the dust from the dust capture mechanism,
Each of the plurality of re-entrainment prevention units is configured by joining a pair of plates to form a mountain shape in a side view,
A ridge portion formed by joining the pair of plates is disposed facing the dust capturing mechanism above,
A dust solidification system in which a slit is provided along the lower end of the plate body between the lower ends of adjacent re-entrainment prevention units to allow the dust to pass downward . The dust re-scattering prevention mechanism is provided,
The dust re-entrainment prevention mechanism further includes an inclined side wall on the outer side of a plate body provided on a re-entrainment prevention unit located at the outermost portion of the plurality of re-entrainment prevention units,
The dust solidification system according to claim 1 , wherein the slits are provided between the lower ends of the plates of the adjacent re-entrainment prevention units and between the outermost re-entrainment prevention unit and the inclined side wall. The dust re-entrainment prevention mechanism includes an upper-stage re-entrainment prevention unit group and a lower-stage re-entrainment prevention unit group formed by the plurality of re-entrainment prevention units,
The dust solidification system according to claim 2 , wherein the ridge portion of each re-entrainment prevention unit of the lower re-entrainment prevention unit group is positioned within the slit formed in the upper re-entrainment prevention unit group in a planar view. A dust solidification method for solidifying dust containing fumes and solidification inhibitors having a mass and size larger than those of the fumes, comprising:
Suctioning dust with a negative pressure generated by a negative pressure generating source, removing solidification-inhibiting substances from the sucked dust, and causing the dust with a reduced content of the solidification-inhibiting substances to flow in a direction toward the negative pressure generating source;
Capturing and dropping the dust flowing due to the negative pressure;
storing the captured and falling dust in a storage tank;
solidifying the dust in a molding chamber by a dust solidifying mechanism;
and
Preventing the falling dust from being re-scattered by a dust re-scattering prevention mechanism;
Agitating the dust fed into the dust solidification mechanism;
and removing air that flows into the storage tank due to the negative pressure from the dust solidification mechanism .
The dust re-entrainment prevention mechanism includes a plurality of re-entrainment prevention units arranged adjacent to each other in a direction transverse to the falling direction of the dust,
Each of the plurality of re-entrainment prevention units is configured by joining a pair of plates to form a mountain shape in a side view,
A ridge portion formed by joining the pair of plates is disposed facing the dust capturing mechanism above,
A slit is provided along the lower end of the plate body between the lower ends of adjacent re-entrainment prevention units to allow the dust to pass downward,
The dust that has slid down the re-entrainment prevention unit is passed through the slit and falls downward.
Dust solidification method.

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