JP5988956B2 - Paint mist collector - Google Patents

Description

The present invention relates to a paint mist collecting device that collects paint mist contained in air to be treated discharged from a coating chamber.
A filter that collects the paint mist contained in the air to be treated discharged from the coating chamber, and a dust agent that is disposed in the air guide passage that guides the air to be treated to the filter and that is to be passed through the air guide passage The filter coating layer for capturing the paint mist, which is an accumulation layer of the powder, is passed through the filter by passing the air to be treated containing the powder sprayed by the powder nozzle in a dispersed state. The present invention relates to a paint mist collecting device for collecting paint mist in a gas to be treated by a filter in a state of being formed on the surface of the filter.

  In patent document 1, in the air guide path (7, 8) which guides the to-be-processed air discharged | emitted from the coating chamber (1) in the state containing the paint mist to the bag filter (11), the air guide path (7, 8) By spraying the dust (auxiliary dust) from the dust nozzle (26) to the air to be treated passing through, the filter coating layer for collecting the paint mist consisting of the dust accumulation layer is applied to the surface of the bag filter (11). A paint mist collecting device is disclosed that collects paint mist in the air to be treated by a bag filter (11) in a state of being formed. (Note that the reference numerals in parentheses are reference numerals used in Patent Document 1).

  By the way, in the conventional paint mist collecting device disclosed in Patent Document 1, a powder mist-containing powder that falls from the surface of the bag filter (11) when the bag filter (11) is regenerated by so-called back washing or the like (that is, After receiving the paint-mixed powder that had previously formed the filter coating layer for capturing the paint mist into the receiving hopper (13), the stock hopper (20 ), A part of the powder containing the paint mist contained in the stock hopper (20) is taken out from the stock hopper (20) through the powder discharge passage (27) and sent to the reprocessing system.

  The powder mist-containing powder remaining in the stock hopper (20) is replenished with a fresh powder that is not mixed with the paint mist, so that the average paint mist content in the stock hopper (20) is averaged. Thus, the powder with reduced paint mist content is taken out from the stock hopper (20) through the powder take-out passage (23), and the powder supply passage (25) together with the carrier air by the pneumatic conveying machine (24). The pressure is supplied to the powder nozzle (26).

  That is, in this paint mist collecting device, a part of the powder in the paint mist-containing state falling from the bag filter (11) is mixed with a fresh powder, and the powder nozzle ( 26) is re-sprayed for circulation.

  Further, in the paint mist collecting device disclosed in Patent Document 1, a powder mist-containing powder in the receiving hopper (13) (that is, a powder that has a tendency to bridge due to the inclusion of the paint mist) is supplied to the pneumatic system. It has been proposed to keep the state dissolved or fluidized, or to keep the powder mist-containing powder in the stock hopper (20) in a fluidized state by using a fluidizing device.

German Patent Publication DE4211465A1

  However, if the paint mist-containing powder in the receiving hopper (13) or the stock hopper (20) is simply disassembled and kept fluidized as described above, the fluidized powder is pneumatically conveyed. Even if the carrier air is pumped to the powder nozzle (26) through the powder supply path (25) together with the carrier air, the dispersion state of the powder in the carrier air in the powder supply path (25) (in other words, the carrier air There is a problem that unevenness and unevenness are easily generated in the concentration of the powder in the powder, and the spraying of the powder from the powder nozzle (26) becomes unstable due to this, and is liable to become defective.

  And due to this, coating layer formation failure such as a part where the formation of the powder accumulation layer as a filter coating layer for capturing paint mist is partially insufficient occurs on the filter surface. There has been a problem that the paint mist is liable to be collected on the filter while directly adhering to the filter surface.

  In order to cope with this problem, if the powder supply amount per unit time to the powder nozzle (26) is made excessive, and a large safety factor is expected in the powder spray amount from the powder nozzle (26), the air pressure There is a problem in that the power required for conveying the powder by the type conveying machine (24) is increased, which is disadvantageous in terms of energy saving.

  In view of this situation, the main problem of the present invention is to effectively solve the above problem by rational improvement.

The first characteristic configuration of the present invention relates to a paint mist collecting device,
A filter that collects paint mist contained in the air to be treated discharged from the painting chamber;
A dust nozzle that is disposed in the air guide path that guides the air to be treated to the filter, and sprays the powder to the air to be treated that passes through the air guide path;
By passing the air to be treated containing the powder sprayed by the powder nozzle in a dispersed state through the filter, a filter coating layer for collecting paint mist consisting of a powder accumulation layer is formed on the surface of the filter. A paint mist collecting device for collecting paint mist in a gas to be treated by the filter,
In the sealed powder tank, a powder dispersion means is provided for dispersing the powder stored in the tank in a uniform floating dispersion state and uniformizing the powder concentration in the air in the tank,
Along with the homogenization of the powder concentration by the powder dispersion means, there is provided an air conveying means for spraying that supplies the powder powder in the suspended dispersion state in the powder tank together with the carrier air to the powder nozzle through the powder supply path. .

  According to this configuration, the powder in the tank is not only fluidized by simply disassembling the powder, but the powder in the tank is uniformly suspended and dispersed by the powder dispersion means (that is, the powder in the air in the tank). Since the powder in the suspended and dispersed state is supplied to the powder nozzle through the powder supply path together with the carrier air by the air supply means for spraying, the conventional paint mist collecting device described above is used. Compared to supplying the powder that has just been clarified and fluidized together with the carrier air to the powder nozzle through the powder supply path, the floating dispersion state of the powder in the carrier air in the powder supply path to the powder nozzle (in other words, (Powder concentration in the carrier air) can be made even more effective, so that the powder from the dust nozzle for the air to be treated As well as uniform and good atomization spray, it is possible to maintain the good powder spray stably.

  As a result, a dust accumulation layer as a filter coating layer for capturing paint mist can be formed in a uniform and good state on the filter surface, whereby the coating in the air to be treated due to poor coating layer formation. It is possible to more effectively prevent the inconvenience that the mist is collected on the filter in a state where the mist is directly adhered to the surface of the filter, and the paint mist collecting device can be further improved in the paint mist collecting property. .

  This also makes it possible to reduce the safety factor expected in the amount of dust sprayed from the dust nozzle, and to avoid excessive powder supply to the dust nozzle as described above. The power required for this can be reduced, and the paint mist collecting device can be made excellent in terms of energy saving.

The second feature configuration of the present invention specifies an embodiment suitable for the implementation of the first feature configuration.
Providing a filter regeneration means for regenerating the filter by dropping the paint mist-containing powder from the surface of the filter, and providing a receiving hopper for receiving the paint mist-containing powder falling from the surface of the filter;
In a state where the inside of the receiving hopper communicates with the inside of the powder tank through the powder discharge port formed at the bottom of the receiving hopper, the powder tank is disposed below the receiving hopper,
A partition door that opens and closes the powder discharge port is provided, and by opening the partition door, the powder mist-containing powder accumulated in the receiving hopper is dropped into the powder tank through the powder discharge port. The powder tank is housed and sealed with the operation of closing the partition door.

  According to this configuration, normally, by closing the partition door and sealing the powder tank, the powder in the tank can be kept in a uniform floating dispersion state by the powder dispersion means in the powder tank. Thereby, as described above, the powder concentration in the carrier air in the powder supply path with respect to the powder nozzle can be effectively uniformed, and a good powder spray from the powder nozzle can be stably maintained. In contrast to performing filter regeneration in a timely manner, the powder mist-containing powder that falls from the filter surface during filter regeneration can be received and temporarily stored in a receiving hopper.

  When the powder in the powder tank decreases to a certain extent, the partition door is opened, and the powder mist-containing powder accumulated in the receiving hopper while the partition door is in the closed state is passed through the powder discharge port. The powder agent tank can be refilled by dropping it into the interior of the container, and then the partition door is closed and the dust agent tank is sealed again, so that the dust agent concentration in the carrier air is made uniform. Powder supply can be resumed promptly.

  In other words, according to this configuration, the dust tank sealing operation and the powder replenishment operation from the receiving hopper to the powder tank can be easily performed only by opening and closing the partition door, thereby simplifying the device configuration. The apparatus cost can be reduced and the operation management of the apparatus can be facilitated.

The third feature configuration of the present invention specifies an embodiment suitable for the implementation of the second feature configuration.
A discharge air conveying means for discharging the powder mist-containing powder contained in the powder tank together with carrier air from the powder tank through the powder discharge path,
There is provided a new agent air conveying means for supplying fresh powder not mixed with paint mist together with carrier air to the powder tank through the new agent supply path.

  In other words, if the powder mist-containing powder accumulated in the receiving hopper is replenished and reused multiple times by opening the partition door, the powder retained in the powder circulation system from the powder tank to the receiving hopper Since the paint mist content of the coating becomes gradually higher and the tendency to form a bridge becomes stronger, the retained powder becomes increasingly unsuitable for spraying from a powder nozzle as a powder for forming a filter coating layer.

  On the other hand, according to the above configuration, when the paint mist content rate of the powder held in the powder circulation system from the powder tank to the receiving hopper becomes high to some extent, the powder is dropped from the receiving hopper by opening the partition door. The powder containing the paint mist contained in the tank is discharged from the powder tank through the powder discharge path together with the carrier air by the discharge air conveying means, and the fresh powder not mixed with the paint mist is newly added together with the carrier air by the new agent air conveying means. By supplying to the powder tank through the powder supply path, the powder held in the powder circulation system from the powder tank to the receiving hopper can be updated.

  And by performing this powder renewal in a timely manner, the paint mist is collected well over a long period of time in a state where a powder accumulation layer as a filter coating layer for capturing paint mist is formed on the filter surface by spraying the powder from the powder nozzle. can do.

  In addition, in the implementation of the above configuration, as a specific embodiment of the powder renewal, a form in which the total amount of the powder held in the powder circulation system is updated at an appropriate time, or the powder held in the powder circulation system for an appropriate time Either a form in which a part is renewed every time, or a form in which powder renewal is continuously carried out in a state where the amount of powder renewal per unit time is limited may be taken, but the powder retained in the powder circulation system If the total amount is updated at a suitable time interval, the frequency of powder update can be reduced, and the operation management of the apparatus can be facilitated accordingly.

The fourth feature configuration of the present invention also specifies an embodiment suitable for the implementation of the second feature configuration.
A discharge air conveying means for discharging the powder mist-containing powder contained in the powder tank together with carrier air from the powder tank through the powder discharge path,
In addition to providing a new agent air conveying means for supplying fresh powder not mixed with paint mist together with carrier air through the new agent supply path,
A supply path switching means for switching a supply path communicating with the powder nozzle between the powder supply path from the powder tank and the new agent supply path is provided.

  According to this configuration, when the paint mist content of the powder in the powder circulation system extending from the powder tank to the receiving hopper becomes high to some extent, the paint that is dropped from the receiving hopper by opening the partition door and stored in the powder tank Mist-containing powder is discharged from the powder tank through the powder discharge path together with carrier air by the discharge air conveying means, and the supply path communicating with the powder nozzle is replaced with the powder supply path from the powder tank. In this state, the fresh powder that has not been mixed with the paint mist is supplied to the powder nozzle through the new agent supply path together with the carrier air by the air carrier for the new agent, and sprayed from the powder nozzle. It is possible to renew the powder held in the circulatory system.

  Then, by performing this powder renewal in a timely manner, as in the case of the third feature configuration, the paint in a state in which a powder accumulation layer as a filter coating layer for capturing paint mist is formed on the filter surface by spraying the powder from the powder nozzle. Mist collection can be carried out well over a long period of time.

  Further, according to this configuration, by keeping the partition door closed, it is possible to update the powder spraying the fresh powder from the powder nozzle in parallel with discharging the powder in the powder tank by the discharge air conveying means. For this reason, even during the renewal of the powder, it is possible to continue the collection of the paint mist accompanied by the spray of the powder from the powder nozzle in a stable state as usual.

  In addition, in the implementation of the above configuration, as a specific embodiment of the powder renewal, a form in which the total amount of the powder held in the powder circulation system is updated at an appropriate time, or the powder held in the powder circulation system for an appropriate time Any of the forms in which a partial amount is updated every time may be adopted.

The fifth feature configuration of the present invention specifies an embodiment suitable for the implementation of the third or fourth feature configuration.
Provided with a control means for automatically executing the powder recovery for opening the partition door for each set recovery time and dropping the paint powder mist-containing accumulated powder in the receiving hopper into the powder tank;
This control means, in addition to the execution of the powder recovery, every time the amount of painting work in the painting chamber reaches a set threshold amount of work, or every time the number of times the partition door opens reaches the set threshold number of times, The powder renewal that discharges the powder mist-containing powder in the powder tank through the powder discharge path by the discharge air conveying means and supplies a predetermined amount of fresh powder through the new agent supply path by the new agent air conveying means Is that it is configured to execute automatically.

  According to this configuration, each of the above-described powder recovery and powder update is automatically executed by the control means, so that the operation management of the apparatus is performed as compared with the case where each of the powder recovery and powder update is performed manually. It can be made much easier.

  In addition, for powder update, as an alternative method, the powder state such as paint mist content and specific gravity of the powder held in the powder circulation system from the powder tank to the receiving hopper is measured by a sensor, and the powder update is performed based on the measurement result. Although it may be possible to have the control means execute it, it is technically difficult to accurately and stably measure the state of the powder with a sensor due to dust characteristics such as sticking and scattering, and large measurement errors are likely to occur. Because of the large measurement error caused by the powder characteristics, there is a risk of causing unexpected troubles in the operation of the apparatus.

  On the other hand, according to the above configuration, instead of the powder update based on the measurement of the powder state, every time the painting work amount in the painting chamber reaches the set threshold work amount, or the number of times the partition door is opened is set to the set threshold number. Since the control means executes the powder update every time it reaches, it is possible to avoid unforeseen troubles due to the large measurement error caused by the powder characteristics as described above, and in this respect, the reliability is further improved. Paint mist collecting device.

Similar to the second feature configuration, the sixth feature configuration of the present invention specifies an embodiment suitable for the implementation of the first feature configuration.
Providing a filter regeneration means for regenerating the filter by dropping the paint mist-containing powder from the surface of the filter, and providing a receiving hopper for receiving the paint mist-containing powder falling from the surface of the filter;
Recirculation air conveying means for returning the powder mist-containing powder deposited inside the receiving hopper to the powder tank through a powder recirculation path together with carrier air;
A discharge air conveying means for discharging the powder mist-containing powder contained in the powder tank together with carrier air from the powder tank through the powder discharge path;
There is provided a new agent air conveying means for supplying fresh powder not mixed with paint mist together with carrier air to the powder tank through the new agent supply path.

  According to this configuration, instead of dropping the accumulated powder in the receiving hopper to the powder tank through the powder discharge port at the bottom of the receiving hopper by opening the partition door as described above, the paint mist containing state accumulated in the receiving hopper is contained. Since the powder is returned to the powder tank through the powder return path together with the carrier air by the air conveying means for recirculation, the powder tank can be kept sealed at all times.

  That is, by always sealing the powder in the powder tank, the powder in the tank can be kept in a uniform floating and dispersed state by the powder dispersion means. As a result, in the carrier air in the powder supply path to the powder nozzle as described above. It is possible to effectively equalize the concentration of the powder and maintain a good powder spray from the powder nozzle stably.

  When the powder in the powder tank is reduced to a certain extent, the powder mist-containing powder accumulated in the receiving hopper is returned to the powder tank through the powder return path along with the carrier air by the recirculation air conveying means. The powder agent can be replenished, whereby the powder agent supply to the powder agent nozzle can be continued in a state where the concentration of the powder agent in the carrier air in the powder agent supply path to the powder agent nozzle is made uniform.

  Further, according to the above configuration, when the paint mist content rate of the powder held in the powder circulation system from the powder tank to the receiving hopper becomes high to some extent, the paint mist containing state returned from the receiving hopper and accommodated in the powder tank The powder is discharged from the powder tank through the powder discharge path together with the carrier air by the air conveying means for discharging, and the fresh powder not mixed with the paint mist is supplied to the powder tank through the new agent supply path together with the carrier air by the air conveying means for the new agent. Thus, it is possible to renew the powder held in the powder circulation system, and by performing this powder renewal in a timely manner, it is possible to satisfactorily collect the paint mist accompanied by the powder spray from the powder nozzle.

  In short, according to the above configuration, the powder agent can be collected from the receiving hopper to the powder tank and the powder renewal for the powder circulation system extending from the powder tank to the receiving hopper can be performed while arranging the powder tank at an appropriate location away from the receiving hopper. Thus, the degree of freedom in selecting the arrangement of each part of the apparatus can be increased, and in this respect, a paint mist collecting apparatus having excellent installation properties and versatility can be obtained.

  In addition, in the implementation of the above configuration, as a specific embodiment of the powder renewal, a form in which the total amount of the powder held in the powder circulation system is updated at an appropriate time, or the powder held in the powder circulation system for an appropriate time Either a mode in which a part amount is updated every time or a mode in which powder update is continuously performed in a state where the amount of powder update per unit time is limited may be adopted.

The seventh feature configuration of the present invention specifies an embodiment suitable for the implementation of the sixth feature configuration.
Provided is a control means for automatically executing powder recovery for returning the powder powder mist-containing accumulated powder in the receiving hopper to the powder tank through the powder reflux path by the return air conveying means for each set recovery time;
In addition to the execution of the powder recovery, the control means is configured so that the number of times the coating work in the coating chamber reaches a set threshold work quantity or the number of times the powder is returned by the recirculation air transfer means is the set threshold number of times. Each time it reaches, the discharge air conveying means discharges the powder mist-containing powder in the powder tank through the powder discharge path, and a predetermined amount of fresh powder through the new agent supply path by the new agent air transfer means Is configured to automatically update the powder supplied to the powder tank.

  According to this configuration, as in the fifth feature configuration described above, each of the powder collection and powder update is automatically executed by the control means, so that each of the powder collection and powder update is performed manually. Compared to the above, the operation management of the apparatus can be made much easier.

  In addition, for powder renewal, as described above, as an alternative method, the powder state such as the paint mist content and specific gravity of the powder held in the powder circulation system from the powder tank to the receiving hopper is measured by a sensor, and based on the measurement result. It is conceivable to have the control unit execute the powder update, but due to the powder characteristics such as sticking and splashing, it is technically difficult to measure the powder state accurately and stably with a sensor, which is a large measurement error. And a large measurement error caused by the powder characteristics may cause unexpected troubles in the operation of the apparatus.

  On the other hand, according to the above configuration, instead of the powder update based on the measurement of the powder state, every time the painting work amount in the painting chamber reaches the set threshold work amount, or the number of times the powder is returned by the recirculation air conveying means Therefore, it is possible to avoid unexpected troubles due to the large measurement error caused by the powder characteristics as described above. It is possible to make a paint mist collecting device which is more excellent in performance.

The eighth characteristic configuration of the present invention specifies an embodiment suitable for the implementation of the sixth or seventh characteristic configuration.
While providing a plurality of paint mist collecting parts provided with the filter, the powder nozzle and the receiving hopper, providing a common powder agent tank for the plurality of paint mist collecting parts,
For each of the plurality of paint mist collecting units, the spray air conveying means for supplying the powder from the common powder tank to the powder nozzle through the powder supply path, and the powder mist-containing powder from the receiving hopper The recirculation air conveying means is provided for returning the air to the common powder tank through the powder recirculation path.

  According to this configuration, a common powder tank is provided for the plurality of paint mist collecting sections, and the powder is supplied from the common powder tank to the powder nozzle of each paint mist collecting section. Since the powder mist-containing powder is returned to the common powder tank from the receiving hopper of the collection part, the entire powder mist collection part is equipped with a separate powder tank, as compared with the whole. The apparatus configuration can be simplified, the apparatus cost can be reduced, and the operation management of the apparatus can be facilitated.

The ninth characteristic configuration of the present invention specifies an embodiment suitable for the implementation of any of the first to eighth characteristic configurations,
An air diffuser plate made of a breathable material allowing permeation of pressurized air is disposed at the bottom of the powder tank, and the upper part of the powder tank accommodates the powder agent inside the powder tank by the air diffuser plate and While partitioning with the lower pressurized air chamber to which the stirring air is pressurized and supplied, a stirring nozzle is provided for ejecting the stirring air to the powder storage chamber,
These aeration plates and agitation nozzles are used as the powder dispersion means, and the agitation air that passes through the aeration plate from the pressurized air chamber and is jetted upward to the powder storage chamber, and the agitation nozzle From the above, the powder contained in the powder storage chamber is dispersed in a uniform floating dispersion state by the stirring air blown into the powder storage chamber.

  According to this configuration, the dust in the powder storage chamber can be lifted in a dispersed state and suspended by the stirring air that permeates through the diffuser plate and is ejected upward with respect to the powder storage chamber. The air in the powder storage chamber can be convectively stirred by the stirring air jetted into the powder storage chamber, and the powder in the powder storage chamber can be convectively stirred. It is possible to effectively disperse the powder in the storage chamber into a uniform floating dispersion state, and it is possible to stably maintain the uniform floating dispersion state.

The tenth characteristic configuration of the present invention specifies an embodiment suitable for the implementation of the ninth characteristic configuration.
While providing a powder delivery chamber adjacent to the powder storage chamber in the powder tank, extending the powder supply path from this powder delivery chamber,
The partition wall that separates the powder storage chamber and the powder delivery chamber is a throttle that restricts the flow rate of the powder flowing in the floating dispersion state from the powder storage chamber to the powder delivery chamber as a communication port that communicates the two chambers. An opening is formed.

  According to this configuration, the floating dispersion state of the powder in the powder storage chamber is stabilized by the ventilation resistance due to the aperture opening, and the inflow of the powder in the floating dispersion state from the powder storage chamber to the powder delivery chamber can be stabilized. It is possible to stabilize the powder supply from the powder delivery chamber through the powder supply path to the powder nozzle, and to stabilize the powder spray from the powder nozzle more effectively. Can do.

The eleventh characteristic configuration of the present invention specifies an embodiment suitable for the implementation of any of the first to tenth characteristic configurations.
The spraying air conveying means for supplying the powder to the powder nozzle through the powder supply path from the powder tank,
The powder is sucked from the powder tank by the negative pressure formed with the passage of the supplied compressed air, the compressed air after forming the negative pressure is used as carrier air, and the sucked powder is sent together with the compressed air after forming the negative pressure. Composed of ejectors,
By adjusting the supply flow rate of the compressed air to the ejector, the supply amount of the powder sprayed from the powder nozzle by adjusting the supply flow rate of the powder to the powder nozzle is provided. .

  According to this configuration, the ejector sucks the powder from the powder tank into the ejector by the negative pressure formed by the compressed air in the ejector, and the sucked powder from the ejector through the powder supply path together with the compressed air (carrier air) after the negative pressure is formed. Since it is supplied to the powder nozzle, as another air conveyance mode, the powder in the powder tank in the floating dispersion state is compared with simply pushing the powder in the powder tank from the powder tank to the powder supply path by compressed air and pumping it to the powder nozzle. The powder can be taken out from the powder tank in a smoother and more stable state, whereby the supply of the powder to the powder nozzle can be more effectively stabilized.

  Further, by adjusting the amount of dust spray from the dust nozzle using the ejector, the amount of dust spray can be adjusted smoothly and stably.

Cross section of painting booth II-II sectional view in FIG. Enlarged sectional view of the inlet The figure which shows the circulation path | route of the powder agent in 1st Embodiment The figure which shows the conveyance path | route of the fresh powder and discharge powder in 1st Embodiment. The figure which shows the circulation route of the powder agent in 2nd Embodiment. The figure which shows the conveyance path | route of the fresh powder and discharge powder in 2nd Embodiment. The figure which shows the circulation route of the powder agent in 3rd Embodiment The figure which shows the conveyance path | route of the fresh powder agent and discharge powder agent in 3rd Embodiment.

[First Embodiment]
FIG. 1 shows a painting booth. This painting booth is provided with a painting chamber 2 for painting an article 1 (automobile body in this example) with a painting gun in the room, and the article 1 is conveyed to the painting chamber 2. A transport device 3 is provided.

  The painting chamber 2 has a tunnel-like indoor space extending in the conveying direction of the article 1 (the depth direction in FIG. 1). The painting chamber 2 has ventilation air whose temperature and humidity are adjusted with respect to the entire tunnel-like chamber. SA is supplied from the ceiling 2a.

  Below the painting chamber 2, an exhaust chamber 4 is formed extending in the conveying direction of the article 1 as in the painting chamber 2, and this exhaust chamber 4 is painted along with the supply of ventilation air SA to the painting chamber 2. The to-be-processed air EA (air containing the floating paint mist produced by the overspray in the coating chamber 2) discharged downward from the chamber 2 through the lattice floor 2b is received.

  That is, as the ventilation air SA is supplied from the ceiling portion 2a of the painting chamber 2, the floating air generated in the painting chamber 2 by discharging the indoor air EA of the painting chamber 2 to the lower exhaust chamber 4 in a piston flow. The paint mist is quickly removed from the coating chamber 2 together with the indoor air EA, thereby maintaining the coating quality of the article 1 to be high and maintaining the working environment of the coating chamber 2 in good condition.

  As shown in FIGS. 1 and 2, a plurality of filter devices 5 are arranged side by side in the coating booth longitudinal direction, which is the conveying direction of the article 1, on both lateral outer sides of the exhaust chamber 4. The paint mist-containing air EA that is discharged from the exhaust chamber 4 and flows into the exhaust chamber 4 is passed through the filter devices 5 so that the paint mist contained in the air EA is collected by the filter device 5 The process air EA is purified.

  The air to be treated EA purified by the filter device 5 (that is, the processed purified air) is discharged to the outside by the exhaust fan 7 through the exhaust duct 6 connected to each filter device 5 (or air-conditioned as ventilation air SA). Return to painting room 2).

  Inside each filter device 5, a plurality of cylindrical filters 8 are arranged side by side in a horizontal orientation, and the side wall 4 a of the exhaust chamber 4 that also serves as the device wall of the filter device 5 is treated with paint mist. As the air guide path for introducing the air EA from the exhaust chamber 4 to the filter device 5 and leading it to the filter 8, two horizontally-long rectangular inlets 10 are formed in each filter device 5.

  That is, due to the suction force applied by the exhaust fan 7 through the exhaust duct 6 connected to the upper part of each filter device 5, the air to be treated EA containing the paint mist is supplied from the exhaust chamber 4 to each filter device 5 through the two inlets 10. It is caused to flow and pass through the filter 8, whereby the paint mist in the air to be treated EA is collected by the filter 8.

  On the other hand, in this paint mist collection, in order to avoid that the paint mist in the air EA to be treated adheres to the surface of the filter 8 and the filter 8 becomes unusable in a short period of time, The inlet 10 is equipped with a powder nozzle 11 that sprays the powder P for forming the filter coating layer against the air to be treated EA passing through the inlet 10.

  That is, the dust P for forming the filter coating layer is dispersed in the air to be treated EA by spraying the dust with the dust nozzle 11 and the air to be treated EA in the dust dispersion state is passed through the filter 8 to collect the dust P. A filter coating layer for capturing the paint mist made of a laminate is formed on the surface of the filter 8, and the paint mist in the air EA to be treated is collected by the filter 8 in such a manner that the filter coating layer captures the paint mist.

  Then, when the content of the captured paint mist in the powder accumulation layer as the filter coating layer is increased to a certain extent in this paint mist collection, a filter regeneration process is performed to drop the powder accumulation layer from the surface of the filter 8, and the powder nozzle 11, the filter coating layer consisting of the dust accumulation layer is formed again on the surface of the regenerated filter 8 by spraying the dust on the air EA to be treated. Thus, the paint mist in the air EA to be treated is filtered by the filter 8. Continue to collect paint mist to be collected.

  The inlets 10 of the plurality of filter devices 5 arranged side by side in the booth longitudinal direction are formed at the lower ends of both side walls 4a of the exhaust chamber 4 in a line in the booth longitudinal direction. The to-be-processed air EA flowing downward into the exhaust chamber 4 is divided into two major flows in the booth width direction, and these two-stream processed air EA maintains a uniform airflow state in the booth longitudinal direction, The interior of the exhaust chamber 4 is skewed toward the inlet 10 located at the lower end of each side wall 4 a of the exhaust chamber 4, and finally the inlet 10 of each filter device 5 near the bottom wall 4 b of the exhaust chamber 4. Evenly divided and inhaled.

  As shown in FIG. 3, a retaining recess 12 having a cross-sectional shape that opens downward is formed on the upper wall portion of each inlet 10 of the filter device 5. It forms over the full width of each inflow port 10 in the state continued in the width direction (namely, booth longitudinal direction).

  More specifically, the upstream edge of the retention recess 12 in the direction of passage of the air to be treated EA at the inflow port 10 is an upstream drooping wall 12a in a vertical posture continuous with the side wall 4a of the exhaust chamber 4, Similarly, the downstream end edge portion of the retention recess 12 is a downstream hanging wall 12b in a vertical posture.

  In addition, an inclined bottom 13 is formed on the lower wall portion of the inlet 10 so as to face the retention recess 12 of the upper wall portion and lower toward the downstream side in the passage direction of the air to be treated EA at the inlet 10. The inclined bottom 13 is also formed over the entire width of each inlet 10 in a state of being continuous in the lateral width direction of the inlet 10.

  Then, in the passage direction of the air to be treated EA at the inflow port 10, the upstream edge of the inclined bottom 13 is an upstream rising wall 13 a in a vertical posture rising toward the upstream drooping wall 12 a of the retention recess 12. is there.

  Each inflow port 10 as a whole has a rectangular tube structure consisting of a retention recess 12 in the upper wall portion, an inclined bottom 13 in the lower wall portion, and both side walls, and an upstream drooping wall 12a of the retention recess 12 and its lower part. An upstream opening 10a having a rectangular tube structure is formed between the upstream side rising wall 13a of the inclined bottom 13 positioned at the downstream side, and the downstream end wall 12b of the retaining recess 12 and the downstream edge of the inclined bottom 13 positioned therebelow. A space between the portion 13b is a downstream opening 10b having a rectangular tube structure.

  Further, in the rectangular tube structure of the inflow port 10, the downstream hanging wall 12b is disposed at a lower position than the upstream hanging wall 12a, so that the downstream opening 10b of the rectangular tube structure is lower than the upstream opening 10a. It is supposed to be located.

  In the inflow port 10 having such a rectangular tube structure, the powder nozzle 11 causes the powder P together with the carrier air a4 from the central portion in the width direction, which is the longitudinal direction of each inflow port 10, toward the inner surface of the back of the retention recess 12. It is arranged to spray.

  That is, in the situation where the flow of the air to be treated EA at the inlet 10 passes near the downward opening of the retention recess 12, the powder P is applied to the inner surface of the back of the retention recess 12 by the powder nozzle 11 as described above. By spraying together with the carrier air a <b> 4, an eddy stagnation of the air flow with the powder P over an appropriate time is generated in the stagnation recess 12.

  Then, the powder P is diffused in the horizontal direction of the inlet 10 in the retention recess 12 while the powder is stirred by the vortex-like residence, and the diffused powder P is diffused in the inlet 10 through the downward opening of the retention recess 12. The air to be treated EA is gradually taken into the passing flow of the air to be treated EA so that the powder P sprayed from the powder nozzle 11 is included in the air to be treated EA in a state of being uniformly dispersed in the lateral width direction of the inlet 10.

  Further, the powder P in the diffusion state in the retention recess 12 is guided downward together with the air flow by the upstream hanging wall 12a and the downstream hanging wall 12b of the retention recess 12, respectively. The height direction (short side direction) is also included in the air to be treated EA in an effectively dispersed state.

  Further, the powder P contained in the flow of the air to be treated EA is changed by causing the flow of the air to be treated EA at the inflow port 10 to be inclined obliquely downward by the downward flow formed by the guide by the downstream drooping wall 12b. Is partially expanded to the downstream portion of the inclined bottom 13 and the powder P is spread on the inclined bottom 13 with a vortex-like residence formed on the inclined bottom 13 due to the influence of the upstream rising wall 13a. Thus, a powder layer is also formed on the inclined bottom 13 to prevent the paint mist from adhering to the inclined bottom 13.

  In addition, since the downstream opening 10b in the rectangular tube structure of the inlet 10 is positioned lower than the upstream opening 10a as described above, the air to be treated EA that has passed through the inlet 10 obliquely downward is obliquely downward. The direction is greatly changed upward so as to be directed to the upper filter 8, and this also further promotes the diffusion of the powder P in the air to be treated EA.

  In addition, 11a is a triangular plate-shaped diffusion auxiliary tool attached to the powder nozzle 11. By arranging this diffusion auxiliary tool 11a, the powder P in the processing target air EA passing through the inflow port 10 and the retention recess 12 is provided. The air staying vortex in a state accompanied with the flow is divided in a state accompanied by the direction change to one side and the other side in the lateral width direction of the inlet 10, and the air to be treated EA and the eddy current staying air accompanying the diversion are Due to the change of direction, the diffusion of the powder P in the retention recess 12 in the lateral direction of the inlet is further promoted, and the powder P in the process of taking the powder P from the retention recess 12 into the passing air of the air EA to be treated. Promotes the spread of

  Further, in the upstream inclined wall surface 12c that forms the upstream upper bottom portion of the retention recess 12, a portion near the upstream hanging wall 12a is provided with a diffusion assist projection 12d that protrudes downward into the retention recess 12. In order to effectively generate the vortex-like staying area in the upstream portion of the staying recess 12 as described above, a part of the dust P and the carrier air a4 ejected from the dust nozzle 11 is used as the upstream inclined bottom wall surface. By colliding with the diffusion auxiliary protrusion 12d under the guidance of 12c, the diffusion of the powder P in the lateral width direction of the inlet is promoted, whereby the flow of the powder P in the retention recess 12 accompanied by stirring due to vortex retention Diffusion is further effectively promoted in the width direction of the entrance.

  As shown in FIGS. 2 and 4, two receiving hoppers 14 each having an inverted cone shape are provided at the bottom of the apparatus below the filter 8 and below the downstream opening 10 b of the inlet 10 in each filter apparatus 5. It arrange | positions in the state arranged in the booth longitudinal direction corresponding to each with respect to the inlet 10, The powder agent discharge port 14a is formed in the bottom part of each of these two receiving hoppers 14. FIG.

  Each filter device 5 is equipped with a filter regeneration device 15 that causes compressed air to act on the filter 8 in a backwashing state opposite to the direction of passage of the air to be treated EA. By operating the regenerator 15 in a timely manner, the above-described filter regeneration process for regenerating the filter 8 is performed by removing the dust accumulation layer as a filter coating layer having a paint mist content rate increased to some extent from the filter surface.

  Then, during the filter regeneration process, the paint mist-containing powder collecting layer (that is, the paint mist-containing powder P) falling from the surface of the filter 8 is received by the receiving hopper 14 below the filter.

  Below each receiving hopper 14, a powder tank 16 is provided continuously for dropping the powder P containing paint mist contained in the receiving hopper 14 into the tank through the powder discharge port 14 a at the bottom of the receiving hopper. Between the hopper 14 and the powder tank 16, a horizontal partition door 17 that opens and closes the powder discharge port 14 a is provided. By opening the partition door 17, the paint mist-containing state received in the receiving hopper 14 is provided. The powder P is dropped into the powder tank 16 and collected in the tank, and the powder tank 16 in the powder storage state is sealed by closing the partition door 17.

  At the bottom of the powder tank 16, a diffuser plate 18 formed of a breathable material that allows the passage of pressurized air due to the presence of dense micropores is arranged over the entire powder tank 16 in plan view. The inside of the powder tank 16 is communicated with the receiving hopper 14 through the powder discharge port 14a by the opening operation of the partition door 17 and the lower pressurized air chamber 16a to which the stirring air a1 is pressurized and supplied through the air passage. The upper powder storage chamber 16b is partitioned.

  In addition, a powder delivery chamber 16c adjacent to the powder storage chamber 16b is formed inside the powder tank 16 on the upper side of the pressurized air chamber 16a, and a partition wall 19 that partitions the powder storage chamber 16b and the powder delivery chamber 16c. As a communication port for communicating between the powder storage chamber 16b and the powder delivery chamber 16c, a throttle opening that restricts the inflow amount of the powder P flowing into the powder delivery chamber 16c from the powder storage chamber 16a with air by a ventilation resistance. 19a is formed.

  And each of the powder storage chamber 16b and the powder delivery chamber 16c is equipped with stirring nozzles 20a and 20b for jetting the stirring air a2 and a3 supplied through the air passages into the respective chambers.

  That is, in the powder storage chamber 16b of the powder tank 16, the stored powder P in the powder storage chamber 16b is transmitted by the stirring air a1 that passes through the diffuser plate 18 from the pressurized air chamber 16a and is jetted upward to the powder storage chamber 16b. Raised in a dispersed state and suspended in the room, and convectively stirred the suspended powder P in the powder storage chamber 16b by convectively stirring the room air with the stirring air a2 ejected from the stirring nozzle 20a, As a result, in the powder tank 16 that is closed and sealed with the partition door 17, the powder P in the powder storage chamber 16 b is not simply released and fluidized, but in a uniform floating dispersion state (that is, in the powder storage chamber 16 b. Maintain a uniform powder concentration in the air).

  The powder P, which has been suspended and dispersed in the powder storage chamber 16b, is sent out of the tank through the throttle opening 19a of the partition wall 19 and the powder delivery chamber 16c. At this time, the powder in the powder storage chamber 16b is caused by the ventilation resistance of the throttle opening 19a. While maintaining a uniform floating dispersion state of P, the powder P in the floating dispersion state is stably allowed to flow from the powder storage chamber 16b to the powder delivery chamber 16c.

  Also in the powder delivery chamber 16c, the powder P in the powder delivery chamber 16c is kept in a uniform floating dispersion state by the stirring air a1 ejected upward from the diffuser plate 18 and the stirring air a3 ejected from the stirring nozzle 20b.

  That is, the air diffusion plate 18 and the stirring nozzles 20a and 20b in the powder tank 16 disperse the powder P in a uniform floating dispersion state inside the sealed powder tank 16 so that the powder concentration in the air in the tank is uniform. Constitutes the powder dispersion means.

  The powder supply passage 21 for supplying the powder P for forming the filter coating layer to the powder nozzle 11 is extended from the powder delivery chamber 16c of the powder tank 16 and connected to the corresponding powder nozzle 11 so that each filter For each inflow port 10 in the apparatus 5, a powder circulation system is formed in the order of the powder nozzle 11 → the receiving hopper 14 → the powder tank 16 → the powder supply path 21.

  In the powder supply path 21 to the powder nozzle 11, the powder P in the powder storage chamber 16 b of the powder tank 16 is sucked through the powder delivery chamber 16 c by the negative pressure formed by the passage of the compressed air a <b> 4 supplied through the air path. In addition, an ejector 22 serving as a jetting air conveying means for feeding the sucked powder P together with the carrier air a4 to the powder nozzle 11 through the powder supply passage 21 using the compressed air a4 after the negative pressure is formed as carrier air is interposed. The powder nozzle 11 sprays the powder P supplied by the ejector 22 onto the air to be treated EA at the inlet 10 together with the carrier air a4.

  Further, by adjusting the flow rate of the compressed air a4 supplied to the ejector 22 to adjust the supply flow rate of the powder P to the powder nozzle 11, the amount of spray per unit time of the powder P sprayed from the powder nozzle 11 is treated air. It adjusts according to the air volume of EA, the paint mist density | concentration in to-be-processed air EA, etc.

  That is, to supply the powder P for forming the filter coating layer to the powder nozzle 11, the powder P is uniformly suspended and dispersed in the powder tank 16 as described above, and the powder P in the suspended dispersion state is supplied to the carrier air by the ejector 22. By supplying to the powder nozzle 11 through the powder supply path 21 together with a4, the floating dispersion state of the powder P in the carrier air in the powder supply path 21 (in other words, the concentration of the powder in the carrier air) is effectively uniformized. Thus, the powder spray from the powder nozzle 11 to the air to be treated EA is sprayed uniformly and satisfactorily, and the good powder spray is stably maintained.

  When the remaining amount of the powder P in the powder tank 16 is reduced to some extent, the partition door 17 is opened, and the paint mist containing state accumulated in the receiving hopper 14 by the filter regeneration process while the partition door 17 is in the closed state is opened. The powder P is dropped and collected in the powder storage chamber 16b of the powder tank 16, and after the recovery, the powder P in the powder storage chamber 16b is uniformly suspended and dispersed with the partition door 17 closed again and the powder tank 16 sealed. In this state, the powder P in the floating dispersion state is supplied to the powder nozzle 11 through the powder supply path 21 and sprayed onto the air to be treated EA, so that the powder P is powdered nozzle 11 → receiving hopper 14 → powder tank 16 → powder. It is used repeatedly in the form of circulation in the order of the supply path 21.

  As shown in FIGS. 4 and 5, the powder supply chamber 21 c of the powder tank 16 in each filter device 5 is connected to a powder supply path 21 to the powder nozzle 11, and the paint mist in the powder storage chamber 16 b of the powder tank 16 is used. A powder discharge path 24 that leads the contained powder P to the common waste tank 23 is connected, and the waste tank 23 passes through these powder discharge paths 24 from the powder tank 16 of each filter device 5 to the paint mist-containing state. Is provided with a suction fan 23a as a discharge air conveying means for discharging the powder P together with the carrier air a5. The powder discharge path 24 may be directly connected to the powder storage chamber 16b instead of being connected to the powder delivery chamber 16c.

  On the other hand, a powder supply chamber 16b of the powder tank 16 in each filter device 5 is connected to a new agent supply path 26 that guides the fresh powder P not mixed with paint mist from the common new agent tank 25 to the powder storage chamber 16b. In the new agent tank 25, the compressed air supplied through the air passage is used as the carrier air a6, and the fresh powder P together with the carrier air a6 is supplied to the dust agent tank 16 in each filter device 5 through the new agent supply passage 26. A blow tank 25a as an air conveying means is provided.

  The powder discharge passage 24 is equipped with a discharge agent side switching valve 24a for switching the powder agent tank 16 to be discharged, and the new agent supply passage 26 is a new agent side switching valve 26a for switching the powder agent tank 16 to be supplied with the new agent. Is equipped.

  Reference numeral 27 denotes a common controller for the filter devices 5, and the common controller 27 executes the following controls (A) to (C).

(A) Filter regeneration control For each filter device 5, the filter regeneration device 15 is operated for each set regeneration time Ts (or every time the measured ventilation resistance of the filter 8 reaches the set threshold resistance value), and the paint mist-containing state The filter covering layer (powder accumulation layer) is removed from the filter surface, and the filter 8 is regenerated.

  This filter regeneration is performed with the partition door 17 of the corresponding powder tank 16 kept closed, and the powder P (powder accumulation layer) containing paint mist falling from the filter 8 is received by the corresponding receiving hopper 14. And deposit.

(B) Powder collection control For each filter device 5, for each set collection time Tk (≧ Ts), the partition door 17 is opened and the powder mist contained in the powder mist containing state in the receiving hopper 14 is stored in the powder tank 16. It is dropped and accommodated in the chamber 16b.

  The set recovery time Tk is set in advance to a time at which the powder P recovered in the powder tank 16 by one opening operation of the partition door 17 is almost used up by spraying the powder from the corresponding powder nozzle 11.

(C) Powder update control For each filter device 5, the amount of coating work in the corresponding area in the painting chamber 2 is set threshold, such as the number of treatments of the object 1 in the corresponding area in the painting chamber 2 reaches the set threshold processing number. Every time the amount of work is reached (or every time the number of times the opening of the partition door 17 reaches the set threshold number), the partition door 17 is opened to drop the deposited powder P of the receiving hopper 14 into the powder tank 16, and then In a state where the partition door 17 is closed, the corresponding powder agent tank 16 is switched to the powder agent tank to be discharged by the switching operation of the discharge agent side switching valve 24a in the dust agent discharge passage 24, whereby the paint in the corresponding dust agent tank 16 is changed. The entire amount of powder P in the mist-containing state is discharged together with the carrier air a5 to the waste tank 23 through the powder discharge path 24.

  Then, following the discharge of the whole amount of the powder P, the switching operation of the new agent side switching valve 26a in the new agent supply path 26 switches the corresponding powder agent tank 16 to the powder agent tank to be supplied with the new agent. A predetermined amount of fresh powder P is supplied from the new agent tank 25 to the powder storage chamber 16b of the powder tank 16 through the new agent supply path 26 together with the carrier air a6.

  That is, by this powder update, in the formation of the filter coating layer by the powder spray from the powder nozzle 11 in each filter device 5, the paint mist content of the retained powder P in the powder circulation system from the powder tank 16 to the receiving hopper 14 is limited to the upper limit. Hold below the value.

[Second Embodiment]
6 and 7 show a second embodiment of the paint mist collecting apparatus according to the present invention. In the paint mist collecting apparatus of the second embodiment, the paint mist collecting apparatus shown in the first embodiment described above is used. The supply route of fresh powder P to the powder circulation system extending from the powder tank 16 to the receiving hopper 14 is modified.

  Specifically, in the first embodiment, the new agent supply path 26 from the new agent tank 25 is connected to the powder agent tank 16, whereas in the second embodiment, the new agent supply path 26 communicates with the powder agent nozzle 11. The supply path is configured to selectively switch between a powder supply path 21 from the powder tank 16 and a new agent supply path 26 from the new agent tank 25 by a three-way valve 30 as a supply path switching means.

  That is, in the paint mist collecting apparatus of the second embodiment, when the powder is renewed, the powder P containing the paint mist in the powder tank 16 is discharged together with the carrier air a5 through the powder discharge passage 24, whereas the three-way valve is used. The communication supply path to the powder nozzle 11 is switched to the new agent supply path 26 from the new agent tank 25 by the switching operation of 30 and is supplied from the new agent tank 25 together with the carrier air a6 through the new agent supply path 26. The fresh powder P is fed to the powder nozzle 11 and sprayed from the powder nozzle 11 onto the air to be treated EA, thereby supplying a predetermined amount of fresh powder P to the powder circulation system from the powder tank 16 to the receiving hopper 14. Update.

  In the paint mist collecting apparatus according to the second embodiment, the new agent supply mode is adopted, so that the powder P containing the paint mist in the powder tank 16 is passed through the powder discharge passage 24 with the partition door 17 closed. Along with discharging the whole amount together with the carrier air a5, the powder can be renewed in a simultaneous progress mode in which the fresh powder P is sprayed from the powder nozzle 11, and the paint accompanied by the dust spray from the powder nozzle 11 even during the powder renewal. Mist collection can be continued in a stable state as usual.

  That is, in the paint mist collecting device of the second embodiment, the common controller 27 performs the following (A) and (F) for the filter regeneration control and the powder recovery control as in the paint mist collecting device of the first embodiment. The control operation is performed as in (b), while the powder update control is performed as in (c).

(A) Filter regeneration control For each filter device 5, the filter regeneration device 15 is operated for each set regeneration time Ts (or every time the measured ventilation resistance of the filter 8 reaches the set threshold resistance value), and the paint mist-containing state The filter covering layer (powder accumulation layer) is removed from the filter surface, and the filter 8 is regenerated.

  This filter regeneration is performed with the partition door 17 of the corresponding powder tank 16 kept closed, and the powder P (powder accumulation layer) containing paint mist falling from the filter 8 is received by the corresponding receiving hopper 14. And deposit.

(B) Powder collection control For each filter device 5, for each set collection time Tk (≧ Ts), the partition door 17 is opened and the powder mist contained in the powder mist containing state in the receiving hopper 14 is stored in the powder tank 16. It is dropped and accommodated in the chamber 16b.

  The set recovery time Tk is set in advance to a time at which the powder P recovered in the powder tank 16 by one opening operation of the partition door 17 is almost used up by spraying the powder from the corresponding powder nozzle 11.

(C ') Powder update control For each filter device 5, the amount of painting work in the corresponding area in the painting chamber 2 is set, such as the number of treatments of the object 1 in the corresponding area in the painting chamber 2 reaches the set threshold processing number. Every time the threshold work amount is reached (or every time the number of opening of the partition door 17 reaches the set threshold number of times), the partition door 17 is opened to drop the accumulated powder P in the receiving hopper 14 into the powder tank 16, and thereafter In a state where the partition door 17 is closed, the corresponding powder agent tank 16 is switched to the powder agent tank to be discharged by the switching operation of the discharge agent side switching valve 24a in the dust agent discharge passage 24. The total amount of the powder P containing the paint mist is discharged into the waste tank 23 through the powder discharge path 24 together with the carrier air a5.

  In addition to the discharge of the whole amount of the powder P, the communication supply path for the corresponding powder nozzle 11 is switched to the new agent supply path 26 from the new agent tank 25 by the switching operation of the three-way valve 30 and the new agent supply path 26, the corresponding powder nozzle 11 is switched to the powder nozzle to be supplied with the new agent by the switching operation of the new agent side switching valve 26a, whereby a predetermined amount of fresh powder P from the new agent tank 25 to the corresponding powder nozzle 11 is switched. Is supplied through the new agent supply path 26 together with the carrier air a6, and the fresh powder P is sprayed onto the air to be treated EA from the corresponding powder nozzle 11 together with the carrier air a6. Continue.

  Then, at the stage of filter regeneration control and powder recovery control, the communication supply path for the corresponding powder nozzle 11 is switched to the powder supply path 21 from the corresponding powder tank 16 by switching operation of the three-way valve 30, thereby The operation returns to the normal paint mist collecting operation in which the powder P is circulated in the order of the tank 16 → the powder nozzle 11 → the receiving hopper 14.

In the paint mist collecting device of the second embodiment, fresh powder P taken out from the new agent tank 25 through the rotary valve 25b is supplied to each powder nozzle 11 through the new agent supply path 26 together with the carrier air a6 by the pressure blower 25c. Like to do.
About another point, it is the same as the coating material mist collection apparatus of 1st Embodiment.

[Third Embodiment]
8 and 9 show a third embodiment of the paint mist collecting device according to the present invention. In the paint mist collecting device of the third embodiment, the paint mist collecting device shown in the first and second embodiments described above is shown. In the collecting device, a modification is added to make the powder tanks 16 common to the plurality of filter devices 5.

  Specifically, in each of the first and second embodiments, each filter device 5 as a paint mist collecting unit including the filter 8, the powder nozzle 11, and the receiving hopper 14 is different from each receiving hopper 14. Whereas the powder tank 16 is continuously provided, in the third embodiment, a common powder tank 16A is provided for the plurality of filter devices 5, and the common powder tank 16A is provided separately from each filter device 5 as appropriate. It is installed in the place.

  And while connecting the powder supply path 21 extended separately from the common powder tank 16A with respect to the powder nozzle 11 of each of the several filter apparatus 5 arrange | positioned along with the coating booth longitudinal direction, it sprays to each of these powder supply paths 21 An ejector 22 is interposed as a working air conveying means.

  Further, each receiving hopper 14 of each filter device 5 is provided with a separate powder recirculation passage 31 for guiding the accumulated powder P in the receiving hopper 14 to the common powder tank 16A. Equipped with a vacuum device 32 as an air conveying means for returning the accumulated powder P in the receiving hopper 14 together with the carrier air a7 to the common powder tank 16A through the powder reflux path 31, and each powder reflux path 31 accepts a powder reflux target. A reflux switching valve 31a for selecting the hopper 14 is interposed.

  At the bottom of the common powder tank 16A, an air diffuser 18 formed of a breathable material that allows the passage of pressurized air due to the presence of dense micropores is arranged across the entire common powder tank 16A in plan view. The inside of the common powder tank 16A is diffused by the air diffuser 18 and the returned pressurized powder from each receiving hopper 14 sucked by the lower pressurized air chamber 16a to which the stirring air a1 is pressurized and supplied through the air passage and the vacuum device 32. It is divided into an upper powder storage chamber 16b for storing P, and the powder storage chamber 16b is equipped with a stirring nozzle 20a for jetting the stirring air a2 supplied through the air passage.

  That is, like each powder tank 16 in the first and second embodiments, in the powder container chamber 16b of the common powder tank 16A, the diffuser plate 18 is transmitted from the pressurized air chamber 16a to the powder container chamber 16b. The stored powder P in the powder storage chamber 16b is lifted in a dispersed state by the stirring air a1 ejected upward and suspended indoors, and the room air is convectively stirred by the stirring air a2 ejected from the stirring nozzle 20a. In this state, the floating powder P in the powder storage chamber 16b is convectively stirred, so that the powder P in the powder storage chamber 16b is not simply fluidized and fluidized in the constantly sealed common powder tank 16A. A uniform floating dispersion state (that is, a state where the concentration of the powder in the air in the powder storage chamber 16b is made uniform) is maintained.

  That is, also in the paint mist collecting device of the third embodiment, the powder P for forming the filter coating layer is applied to the powder nozzle 11 of each filter device 5 as in the paint mist collecting device of the first and second embodiments. As described above, the powder P is uniformly suspended and dispersed in the common powder tank 16A, and the powder P in the suspended and dispersed state is supplied to each powder nozzle 11 through the ejector 22 and the carrier air a4 through the powder supply passage 21. By doing so, the floating dispersion state of the powder P in the carrier air in the powder supply passage 21 (in other words, the concentration of the powder in the carrier air) is effectively uniformed, and thereby the powder nozzle 11 for the air to be treated EA. As a result, the powder spray is uniformly and satisfactorily sprayed, and the powder spray is kept stable.

  A powder supply path 21 to each powder nozzle 11 is connected to the powder storage chamber 16b of the common powder tank 16A, and a powder discharge that guides the powder P containing paint mist in the powder storage chamber 16b to a common waste tank 23. A passage 24 is connected to the waste agent tank 23, and a discharge air conveying means for discharging the powder P containing paint mist together with the carrier air a5 from the dust storage chamber 16b of the common dust tank 16A through the dust discharge passage 24. As a suction fan 23a.

  Further, a new agent supply path 26 is connected to the powder agent storage chamber 16b of the common powder agent tank 16A. The new agent supply path 26 guides the fresh powder agent P not mixed with paint mist from the common new agent tank 25 to the powder agent storage chamber 16b. 25, a new agent air conveying means for supplying compressed air supplied through the air passage as carrier air a6 and supplying fresh powder P together with the carrier air a6 through the new agent supply passage 26 to the powder containing chamber 16b of the common powder tank 16A. As a blow tank 25a.

  And in the paint mist collection apparatus of this 3rd Embodiment, the common controller 27 performs the following control (d)-(f).

(D) Filter regeneration control For each filter device 5, the filter regeneration device 15 is operated for each set regeneration time Ts (or every time the measured ventilation resistance of the filter 8 reaches the set threshold resistance value), and the paint mist-containing state The filter covering layer (powder accumulation layer) is removed from the filter surface, and the filter 8 is regenerated.

  Then, the powder P (powder accumulation layer) containing paint mist falling from the filter 8 is received and deposited in the corresponding receiving hopper 14.

(E) Powder recovery control In the form in which each receiving hopper 14 of the plurality of filter devices 5 is made into a receiving hopper subject to powder reflux by sequentially opening and closing the reflux switching valve 31a, in each receiving hopper 14 of the plurality of filter devices 5 The accumulated powder P containing the paint mist is collected in the powder storage chamber 16b of the common powder tank 16A together with the carrier air a7 through the corresponding powder reflux path 31 for each set recovery time Tk (≧ Ts).

(F) Powder update control The number of treatments of the article 1 in the corresponding area in the coating chamber 2 (here, the corresponding area for a plurality of filter devices 5 sharing one common powder tank 16A) becomes the set threshold processing number. Each time the amount of painting work in the corresponding area in the painting chamber 2 reaches the set threshold amount of work (or every time the number of times the powder returns from each receiving hopper 14 reaches the set threshold number), the common powder tank 16 The total amount of the powder P containing the paint mist is discharged into the waste tank 23 through the powder discharge path 24 together with the carrier air a5.

  Then, following the discharge of the entire amount of the powder P, a predetermined amount of fresh powder P is supplied from the new agent tank 25 to the powder storage chamber 16b of the common powder tank 16 through the new agent supply path 26 together with the carrier air a6.

  That is, by this powder update, in the formation of the filter coating layer by spraying the powder from the powder nozzle 11 in each filter device 5, the paint mist containing the powder P to be circulated in the order of the common powder tank 16A → the powder nozzle 11 → the receiving hopper 14 is contained. Keep the rate below the upper limit.

  In the paint mist collecting device of the third embodiment, vibration is generated on the inclined side wall of the receiving hopper 14 in each filter device 5 by the compressed air a8 supplied through the air passage, and the generated vibration is received by the receiving hopper. It is equipped with a bridge breaker 33 that propagates to 14 inclined side walls.

  That is, when returning the accumulated powder P in each receiving hopper 14 to the common powder tank 16A through the powder recirculation path 31, the bridge breaker 33 is vibrated to ensure that the accumulated powder P in the receiving hopper 14 is received. 14 is slid down to the bottom of 14 (that is, the inlet opening of the powder reflux path 31).

  About another point, it is the same as the coating material mist collection apparatus of 1st, 2nd embodiment.

[Another embodiment]
Next, other embodiments of the present invention will be listed.

  The filter device 5 is not limited to the one in which the plurality of filters 8 are installed in the horizontal orientation, but may be one in which one or a plurality of filters 8 are installed in the vertical orientation or the oblique orientation.

  The arrangement location of the powder nozzle 11 is not limited to the inlet 10 of the filter device 5, and may be arranged at any location as long as it is an air guide path that guides the air to be treated EA discharged from the coating chamber 2 to the filter 8. May be.

  In the sealed powder tanks 16 and 16A, the powder dispersion means for dispersing the powder P accommodated in the tank in a uniform floating dispersion state and uniformizing the powder concentration in the air in the tank is shown in each of the foregoing embodiments. The diffuser plate 18 and the stirring nozzles 20a and 20b are not limited, and various types can be adopted as long as the powder P in the tank can be dispersed in a uniform floating dispersion state.

  The spraying air conveying means for supplying the powder P in the suspended dispersion state in the powder tanks 16 and 16A together with the carrier air a4 to the powder nozzle 11 through the powder supply passage 21 is not limited to the ejector 22, and adopts various air conveying methods. be able to.

  The filter regeneration means for regenerating the filter 8 by dropping the powder P containing paint mist from the surface of the filter 8 causes the compressed air to act on the filter 8 in a direction opposite to the passing direction of the air EA to be treated. Any type of regeneration system may be used, including a system and a system that mechanically applies vibration to the filter 8.

  Discharge air conveying means for discharging the powder mist-containing powder P contained in the powder tanks 16 and 16A from the powder tanks 16 and 16A through the powder discharge passage 24 together with the carrier air a5, and fresh powder P not containing paint mist. The air transport means for the new agent for supplying the air to the powder tanks 16 and 16A or the powder nozzle 11 through the new agent supply path 26 together with the carrier air a6 is not limited to the system shown in the above-described embodiments, but various air A conveyance type can be adopted.

  Also, the air conveying means for reflux for returning the powder mist containing paint P accumulated in the receiving hopper 14 to the powder tank 16A through the powder reflux path 31 together with the carrier air a7 is the same as that shown in the third embodiment. Not limited to this, various types of conveyance methods can be adopted.

  In each of the above-described embodiments, the paint mist contained in the air to be treated EA discharged from the coating chamber 2 is shown to be shared and collected by the plurality of filter devices 5 arranged in parallel. The present invention can also be applied to a case where the paint mist contained in the air to be treated EA discharged from 2 is collected by a single filter device 5.

  The object 1 to be coated in the painting chamber 2 is not limited to an automobile body, but may be any part such as an automobile part such as a bumper, a body of an orbital vehicle or an airplane, a home appliance, or a steel material.

  The paint mist collecting device according to the present invention can be used in various painting facilities in various fields where the air to be treated EA containing the paint mist is discharged.

2 Coating chamber EA Air to be treated 8 Filter 10 Air guide path P Dust agent 11 Dust agent nozzle 16, 16A Dust agent tank 18 Dust dispersing means, diffuser plate 20a, 20b Dust dispersing means, stirring nozzle a4 Carrier air 21 Dust supply path 22 Spray Air transport means, ejector 15 Filter regeneration means 14 Receiving hopper 14a Dust outlet 17 Partition door a5 Carrier air 24 Dust discharge path 23a Discharge air transport means a6 Carrier air 26 New agent supply path 25a New agent air transport means 30 Supply Route switching means Tk Setting recovery time 27 Control means a7 Carrier air 31 Powder recirculation path 32 Air supply means for recirculation 5 Paint mist collecting part 16b Powder storage chamber a1 Stirring air 16a Pressurized air chamber 16c Powder delivery chamber 19 Partition wall 19a Aperture aperture

Claims (11)

A filter that collects paint mist contained in the air to be treated discharged from the painting chamber;
A dust nozzle that is disposed in the air guide path that guides the air to be treated to the filter, and sprays the powder to the air to be treated that passes through the air guide path;
By passing the air to be treated containing the powder sprayed by the powder nozzle in a dispersed state through the filter, a filter coating layer for collecting paint mist consisting of a powder accumulation layer is formed on the surface of the filter. A paint mist collecting device for collecting paint mist in a gas to be treated by the filter,
In the sealed powder tank, a powder dispersion means is provided for dispersing the powder stored in the tank in a uniform floating dispersion state and uniformizing the powder concentration in the air in the tank,
Along with the homogenization of the powder concentration by the powder dispersion means, a paint mist trap provided with a spray air conveying means for supplying the powder in a suspended dispersion state in the powder tank together with carrier air to the powder nozzle through the powder supply path. Collector. Providing a filter regeneration means for regenerating the filter by dropping the paint mist-containing powder from the surface of the filter, and providing a receiving hopper for receiving the paint mist-containing powder falling from the surface of the filter;
In a state where the inside of the receiving hopper communicates with the inside of the powder tank through the powder discharge port formed at the bottom of the receiving hopper, the powder tank is disposed below the receiving hopper,
A partition door that opens and closes the powder discharge port is provided, and by opening the partition door, the powder mist-containing powder accumulated in the receiving hopper is dropped into the powder tank through the powder discharge port. The paint mist collecting apparatus according to claim 1, wherein the paint mist collecting device is configured to contain and seal the powder tank in a powder containing state by closing the partition door. A discharge air conveying means for discharging the powder mist-containing powder contained in the powder tank together with carrier air from the powder tank through the powder discharge path,
3. The paint mist collecting device according to claim 2, further comprising a new agent air conveying means for supplying fresh powder not mixed with paint mist together with carrier air to the powder tank through a new agent supply path. A discharge air conveying means for discharging the powder mist-containing powder contained in the powder tank together with carrier air from the powder tank through the powder discharge path,
In addition to providing a new agent air conveying means for supplying fresh powder not mixed with paint mist together with carrier air through the new agent supply path,
3. The paint mist collecting device according to claim 2, further comprising supply path switching means for switching a supply path communicating with the powder nozzle between the powder supply path from the powder tank and the new agent supply path. Provided with a control means for automatically executing the powder recovery for opening the partition door for each set recovery time and dropping the paint powder mist-containing accumulated powder in the receiving hopper into the powder tank;
This control means, in addition to the execution of the powder recovery, every time the amount of painting work in the painting chamber reaches a set threshold amount of work, or every time the number of times the partition door opens reaches the set threshold number of times, The powder renewal that discharges the powder mist-containing powder in the powder tank through the powder discharge path by the discharge air conveying means and supplies a predetermined amount of fresh powder through the new agent supply path by the new agent air conveying means The paint mist collecting device according to claim 3 or 4, wherein: Providing a filter regeneration means for regenerating the filter by dropping the paint mist-containing powder from the surface of the filter, and providing a receiving hopper for receiving the paint mist-containing powder falling from the surface of the filter;
Recirculation air conveying means for returning the powder mist-containing powder deposited inside the receiving hopper to the powder tank through a powder recirculation path together with carrier air;
A discharge air conveying means for discharging the powder mist-containing powder contained in the powder tank together with carrier air from the powder tank through the powder discharge path;
2. A paint mist collecting device according to claim 1, further comprising: a new agent air conveying means for supplying fresh powder not mixed with paint mist together with carrier air to the powder tank through a new agent supply path. Provided is a control means for automatically executing powder recovery for returning the accumulated powder powder containing paint mist in the receiving hopper to the powder tank by the return air conveying means for each set recovery time;
In addition to the execution of the powder recovery, the control means is configured so that the number of times the coating work in the coating chamber reaches a set threshold work quantity or the number of times the powder is returned by the recirculation air transfer means is the set threshold number of times. Each time it reaches, the discharge air conveying means discharges the powder mist-containing powder in the powder tank through the powder discharge path, and a predetermined amount of fresh powder through the new agent supply path by the new agent air transfer means The paint mist collecting apparatus according to claim 6, wherein the powder renewal is automatically performed to supply the powder to the powder tank. While providing a plurality of paint mist collecting parts provided with the filter, the powder nozzle and the receiving hopper, providing a common powder agent tank for the plurality of paint mist collecting parts,
For each of the plurality of paint mist collecting units, the spray air conveying means for supplying the powder from the common powder tank to the powder nozzle through the powder supply path, and the powder mist-containing powder from the receiving hopper The paint mist collecting device according to claim 6 or 7, further comprising a return air conveying means for returning the air to the common powder tank through the powder reflux path. An air diffuser plate made of a breathable material allowing permeation of pressurized air is disposed at the bottom of the powder tank, and the upper part of the powder tank accommodates the powder agent inside the powder tank by the air diffuser plate and While partitioning with the lower pressurized air chamber to which the stirring air is pressurized and supplied, a stirring nozzle is provided for ejecting the stirring air to the powder storage chamber,
These aeration plates and agitation nozzles are used as the powder dispersion means, and the agitation air that passes through the aeration plate from the pressurized air chamber and is jetted upward to the powder storage chamber, and the agitation nozzle The paint according to any one of claims 1 to 8, wherein the powder stored in the powder storage chamber is dispersed in a uniform floating dispersion state by the stirring air jetted from the powder storage chamber to the powder storage chamber. Mist collecting device. While providing a powder delivery chamber adjacent to the powder storage chamber in the powder tank, extending the powder supply path from this powder delivery chamber,
The partition wall that separates the powder storage chamber and the powder delivery chamber is a throttle that restricts the flow rate of the powder flowing in the floating dispersion state from the powder storage chamber to the powder delivery chamber as a communication port that communicates the two chambers. The paint mist collecting device according to claim 9, wherein an opening is formed. The spraying air conveying means for supplying the powder to the powder nozzle through the powder supply path from the powder tank,
The powder is sucked from the powder tank by the negative pressure formed with the passage of the supplied compressed air, the compressed air after forming the negative pressure is used as carrier air, and the sucked powder is sent together with the compressed air after forming the negative pressure. Composed of ejectors,
2. A spray amount adjusting means for adjusting the amount of powder supplied to the powder nozzle and adjusting the amount of powder sprayed from the powder nozzle by adjusting the supply flow rate of compressed air to the ejector. The paint mist collection apparatus of any one of 10-10.

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