JPH05146727A - Device for removing mist of coating material - Google Patents

Abstract

PURPOSE:To improve the efficiency of capturing the mists of coating material and to decrease the noises leaking out to a coating chamber. CONSTITUTION:The liquid drops capturing the mists of the coating material in the gas passing a washing area S1 are received in the lower part of the washing area S1. An upward sloping wall surface (a) which guides the downflow of the liquid gathering the received liquid drops and a downward wall surface (c) which is continuous with the lower edge of this upward sloping wall surface (a) are formed in a throttling wind path. The throttling wind path 12 is so constituted that the air flow A in the wind path deflects toward the downward wall surface (c) in a wall surface deflecting part (b) between the upward sloping wall surface (a) and the downward wall surface (c). A 2nd liquid releasing part H2 for a 2nd washing area S2 which peels and splashes the downflow washing liquid W1 from the upward sloping wall surface (a) by directing the wall surface deflecting part (b) toward the prescribed washing area S2 below the downward wall surface (c) in the throttling wind path 12 in the state of entailing the formation of the finer grains in the air flow A in the wind path is provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention is provided with a throttle air passage for passing a paint mist-containing gas from a coating chamber together with a cleaning liquid at a high speed and discharging it to an exhaust chamber, and flows downward from an air passage inlet into the throttle air passage. The present invention relates to a paint mist removing device provided with a liquid spouting portion that scatters a cleaning liquid toward a predetermined cleaning area below the inlet of the air passage in the narrowed air passage in a state of being atomized in the air flow.

[0002]

2. Description of the Related Art A paint mist removing device of the above type is shown in FIG.
As shown in, the air passage inlet 12a in the throttle air passage 12
In a predetermined cleaning area S1 below the cleaning area S1, a droplet collecting area of the cleaning liquid W scattered from the liquid spraying portion H1 in a state accompanied by atomization is formed, whereby the paint mist in the passing gas A in the cleaning area S1. To collect and remove the paint mist from the gas A. The cleaning area S1 which is a droplet collecting area is
By forming it in the middle of the throttle wind passage 12 in which the air flow velocity is maintained at a high speed, for example, the throttle air passage 12 in which the air flow velocity is greatly reduced with the discharge from the throttle air passage 12 to the exhaust chamber 11.
This is to make it possible to obtain a high paint mist collection efficiency as compared with the case where a cleaning area is formed at a position after being discharged from the.

Conventionally, in this type of paint mist removing device, as shown in FIG. 4, a one-step cleaning area S1 below the air passage inlet 12a in the throttle air passage 12 and a one-stage liquid sprayer corresponding thereto. Only the part H1 was provided.

[0004]

However, in recent years, it has been desired to further improve the efficiency of collecting paint mist, but in order to increase the air flow velocity, the air passage cross-sectional area of the throttle air passage 12 is reduced. By increasing the amount of cleaning liquid that passes through the throttled air passage 12 together with the gas A, the paint mist collection efficiency is improved, but due to such a reduction in the air passage cross-sectional area and an increase in the amount of cleaning liquid. As the pressure loss in the throttle air passage 12 increases, the noise leaking from the throttle air passage 12 to the coating chamber 1 (mainly the scattering noise of the cleaning liquid) also greatly increases, which causes a deterioration of the working environment in the coating chamber 1. was there.

An object of the present invention is to make it possible to obtain a high paint mist collecting efficiency while effectively reducing the noise leaking into the coating chamber by a rational improvement.

[0006]

The paint mist removing device according to the present invention is characterized in that the paint mist-containing gas from the coating chamber is passed through the cleaning liquid at a high speed and is discharged to the exhaust chamber. Basic configuration in which a liquid spouting portion is provided to scatter the cleaning liquid toward a predetermined cleaning area below the inlet of the air duct in the throttle air duct in the state of being atomized in the airflow flowing downward from the air duct to the throttle air duct. On the other hand, the upward inclined wall surface that receives the droplet that has captured the paint mist in the passing gas in the cleaning area below the cleaning area and guides the downward flow of the collected droplet of the collected liquid, and the upward inclined wall surface Forming a downward wall surface connected to the lower edge in the throttle air passage,
The narrowed air passage is configured such that the airflow in the air passage is turned to the side of the downward wall surface at the wall turning portion between the upward inclined wall surface and the downward wall surface, and A second cleaning area for separating and splashing the falling cleaning liquid from the upward inclined wall surface toward a predetermined second cleaning area below the downward wall surface in the narrowed air passage in the state of being atomized in the air flow in the passage. It exists as a two-liquid spouting part, and its actions and effects are as follows.

[0007]

That is, in the above-mentioned characteristic structure (see FIG. 2), first, in the predetermined cleaning area S1 below the air passage inlet 12a in the throttle air passage 12, a state in which the liquid spouting portion H1 is accompanied by atomization. The paint mist in the downward passing gas A from the air passage inlet 12a is captured by the droplets of the cleaning liquid W scattered in 1., whereby the first-stage paint mist is collected.

Thereafter, the droplets that have captured the paint mist in the cleaning area S1 are received by the upward inclined wall surface a below the cleaning area S1, and the collected liquid W1 of the received droplets is turned into a high-speed gas flow in the squeezing air passage. Along with this, it is made to flow down along the upwardly inclined wall surface a, and subsequently, at the wall surface turning portion b between the upwardly inclined wall surface a and the downward wall surface c connected to the lower edge thereof, the airflow A in the air passage is directed toward the downward wall surface c. With the change to
The downwashing liquid W1 from the upward inclined wall surface a is separated and scattered toward the predetermined second cleaning area S2 below the downward wall surface c in the narrowed air passage in a state accompanied by the atomization in the air flow in the air passage, thereby , A droplet collecting region where the cleaning liquid W1 is atomized and scattered in the second cleaning region S2.

That is, the wall surface turning portion b is squeezed downstream to the second cleaning area S2 in the middle of the downstream squeezing air passage.
As 2, the droplet collecting area similar to the upstream cleaning area S1 is re-formed in the second cleaning area S2, and the residual paint mist in the passing gas A is trapped in the droplets in the second cleaning area S2. , The second-stage paint mist collection subsequent to the first-stage paint mist collection is performed in the squeezing air passage.

On the other hand, in the above-described two-stage collecting mode, noise generated by collecting the second-stage paint mist, that is, on the downstream side of the wall surface turning portion b as the second liquid discharging portion H2. Regarding the noise generated in the throttled air passage portion, the downstream side throttled air passage portion is viewed from the upstream cleaning area S1 due to the presence of the downward wall surface c and the upward inclined wall surface a (in other words, the inlet of the throttle air passage 12). Since the large number of droplets located in the blind spot position (as viewed from the side of 12a) and in the upstream cleaning region S1 have a high sound absorbing action as the original property of the droplets, noise generated by the second stage paint mist collection Squeeze airway entrance 12
Leakage to the a side is effectively suppressed.

[0011]

As a result of the above operation, according to the characteristic configuration of the present invention, the paint mist is collected in a form in which the cleaning area is formed in the middle of the air passage (that is, the cleaning area, which is a droplet collecting area, has an air velocity. The paint mist is collected in the middle of the squeezing air passage to maintain high speed.
Is performed in two stages during the passage in the throttle air passage, it is possible to obtain a very high paint mist collecting efficiency as a whole.

Moreover, while ensuring a high paint mist collecting efficiency as described above, it is possible to effectively prevent the noise generated by the second-stage paint mist collecting from leaking to the inlet side of the throttled air passage. As shown in Fig. 4, compared with the conventional type in which only a one-step cleaning area is provided below the inlet of the air passage, the efficiency of paint mist collection is improved by reducing the cross-sectional area of the air passage and increasing the amount of cleaning liquid. It is possible to reduce the noise leaking from the throttle passage to the coating room side, and improve the working environment in the coating room.

Incidentally, in order to collect the paint mist in two steps, as an alternative method, as shown in FIG. 3, the paint mist-containing gas A from the coating chamber 1 together with the cleaning liquid W is collected in the same one-step manner as in the conventional case. The cleaning liquid W that has passed through the upstream throttle air passage 12A at high speed is discharged to the upstream exhaust chamber 11A, and the cleaning liquid W discharged to the upstream exhaust chamber 11A is stored in the intermediate cleaning liquid tank 1
0A, and subsequently, the gas A in the upstream side exhaust chamber 11A, together with the overflow cleaning liquid W from the intermediate cleaning liquid tank 10A, flows at high speed in the downstream throttle air passage 12B, which also has the same one-stage trapping configuration as the conventional one. A form in which the paint is passed through and discharged to the downstream side exhaust chamber 11B (that is, a form in which the paint mist collection in the conventional form shown in FIG. 4 is simply performed in two stages) is also conceivable.

However, in this type, the trapped paint component in the cleaning liquid W discharged from the upstream throttle air passage 12A to the upstream exhaust chamber 11A is stored in the intermediate cleaning liquid tank 10A in the cleaning liquid storage process (that is, the first-stage paint mist). In the process from the collecting process to the second stage paint mist collecting process), the number of places requiring cleaning maintenance increases, and the exhaust chambers are divided into the upstream exhaust chamber 11A and the downstream exhaust chamber 11B. Each exhaust chamber 11A, 11
Since the maintenance work itself for B becomes difficult to perform, the maintainability is drastically reduced, and in order to prevent the paint accumulation in the intermediate cleaning liquid tank 10A, the cleaning liquid W discharged from the upstream throttle air passage 12A is discharged to the downstream side. Baffle 12B
If the form in which the fresh cleaning liquid is supplied to the downstream throttled air passage 12B is adopted instead of the form in which the cleaning liquid is reused, the amount of the necessary cleaning liquid as a whole is greatly increased, and the running cost is increased.

In this respect, according to the characteristic configuration of the present invention (see FIG.
In the process from the first-stage paint mist collecting step to the second-stage paint mist collecting step, the cleaning liquid W1 flows down the upwardly inclined wall surface a at a high speed due to the high-speed gas flow in the restricted air passage 12, Although the cleaning liquid W used for collecting the paint mist by the eye is reused for collecting the paint mist by the second step, it extends from the paint mist collecting step of the first step to the paint mist collecting step of the second step. The coating material can be effectively prevented from being accumulated in the process, and the exhaust chamber 11 does not need to be divided into two parts. Therefore, it is possible to avoid the deterioration of the maintainability and avoid the increase of the required cleaning liquid amount to reduce the running cost. There is an advantage that an increase can be avoided.

[0016]

EXAMPLES Next, examples will be described.

FIG. 1 shows a coating booth forming a tunnel-shaped coating chamber 1. The ceiling of the coating chamber 1 has a blow-out port 3 for blowing downward ventilation air supplied from an air conditioner 2, and the coating is performed. The floor of the chamber 1 is provided with a lattice floor 5 which allows the indoor air A to be discharged downward by the suction action of the exhaust fan 4. With this ventilation structure, the lattice floor 5 is generated in the coating chamber 1 during spray coating. Excessive paint mist floating in the room is discharged together with the room air A from the coating room 1.

In the figure, 6 is an object to be coated, 7 is a conveyor device for conveying the object, and 8 is a spray coating machine.

Below the lattice floor 5, there is provided a pair of wash water tanks 10 for maintaining a water-tight state by overflowing the wash water W from the overflow gutter 9, and below the wash water tanks 10 are provided an exhaust chamber 11. A slit-like opening 12 extending in the longitudinal direction of the booth between the both wash water tanks 10 is provided as an exhaust air passage configuration from the upper region of the wash water tank 10 to the exhaust chamber 11.
The throttle air passage 12 having a as an air passage inlet is provided continuously in the longitudinal direction of the booth.

The throttle air passage 12 allows the exhaust air A from the coating chamber 1 to pass at high speed together with the overflow wash water W from the wash water tank 10 to collect the paint mist in the exhaust air A by the wash water W. It constitutes a paint mist removing device, and the exhaust air A purified by removing the paint mist is discharged from the exhaust chamber 11 via the drainer 13 and is discharged to the outside of the system via the exhaust fan 4 and the exhaust duct 14.

The cleaning liquid W which has captured the paint mist in the exhaust air A in the above-mentioned paint mist removal is the coating chamber 11
After receiving it in the return water tank 15 at the bottom, a suitable separating device 1
In step 6, the coating material contained is separated and removed for purification, and then circulated and supplied to the overflow gutter 9 for reuse.

As for the concrete structure of the throttled air passage 12, as shown in FIG. 2, the first washing area S1 is set in the air passage immediately below the air passage inlet 12a, and the squeezed air in both washing water tanks 10 is set. The overflow weir 17 to the path 12 is set to the above first
The first wash water spouting portion H1 for the wash area S1 is used, and the wash water W is discharged from the first wash water spouting portion H1 in the downward airflow direction A from the airway inlet 12a in a state accompanied by atomization. It is configured to scatter toward the first cleaning area S1.

That is, with the above structure, a water droplet collecting area of the wash water W which is scattered from the first wash water spouting portion H1 in a state accompanied with atomization is formed in the first wash area S1 in the throttle air passage, As a result, the downward passing gas A in the first cleaning area S1
The paint mist in the inside is captured by water droplets to collect the first-stage paint mist.

Of the side wall 18 of the throttled air passage 12, a portion 18A extending from the air passage inlet 12a to the first cleaning area S1 is a vertical wall, whereas a portion 18B below the first cleaning area S1. 18C is formed in a V-shaped cross-sectional shape that bulges inside the air passage, whereby the first cleaning area S1 is formed.
An upward inclined wall surface a that receives the water droplets that have captured the paint mist at the lower side of the first cleaning area S1 and causes the collected water W1 of the received water droplets to flow down along the upper surface at a high speed along with the high-speed gas flow in the throttle air passage, Further, a downward wall surface c which is connected to the lower edge of the upward inclined wall surface a via a wall surface changing portion b is formed in the air passage.

On the other hand, with respect to the other side wall 19 of the throttle air passage 12, the upstream side portion 19A is a vertical wall, while the downstream side portion 19B is arranged in a front-down inclined posture substantially parallel to the downward wall surface c. In this way, the downstream side portion of the throttle air passage 12 is used as a downward inclined air passage, and the airflow A in the air passage is diverted to the side of the downward wall surface c at the wall surface diverting portion b.

In other words, with the above-described air passage structure after the first cleaning area S1, the air flow path A in the air passage is turned toward the downward wall surface c at the wall turning portion b.
The washing water W1 flowing downward from the wall surface is separated and scattered from the wall surface turning portion b toward the predetermined second cleaning area S2 below the downward wall surface c in the restricting air passage in the state of being atomized in the air flow A in the air passage. As a result, the wall surface deflecting portion b is used as the second cleaning water spouting portion H2 for the second cleaning area S2, and the same water droplet collecting area as the upstream first cleaning area S1 is reformed in the second cleaning area S2. Therefore, by catching the residual paint mist in the passing gas A in the second cleaning zone S2 by water droplets, the second-stage paint mist collection subsequent to the upstream first-stage paint mist collection is squeezed. This is done in the air passage 12.

Further, in the above-described air passage structure, the throttle air passage portion on the downstream side of the wall surface deflecting portion b is provided with the upward inclined wall surface a and the downward wall surface c, so that the first cleaning area S1 and the squeeze air above the first cleaning area S1. When the blind spot is seen from the passage inlet 12a, moreover, a large number of water droplets in the first cleaning area S1 are absorbed by the high sound absorption characteristic of the water droplets in response to the noise generated in the throttle wind passage portion on the downstream side of the wall surface turning portion b. The noise reduction function of the noise reduces the noise (mainly water splattering noise) generated in the throttle wind passage downstream of the wall turning portion b in order to collect the paint mist in the second stage. While suppressing leakage to the inlet 12a side, and thereby ensuring high paint mist collecting efficiency as a whole by the paint mist collecting in two stages described above,
It is intended to effectively reduce the noise leaking from the squeeze air passage 12 to the side of the coating room 1 to improve the working environment in the coating room 1.

On the side of the other side wall 19 of the first cleaning area S1 in the restricted air passage 12, a cavity 20 is formed which is surrounded on three sides by the bottom of the wash water tank 10 and the other side wall 19 of the restricted air passage 12. However, the presence of the hollow portion 20 also contributes to the reduction of leakage noise from the throttle air passage 12 to the coating chamber 1 side.

In the throttle air passage 12, the air passage cross-sectional area at the wall surface turning portion b as the second wash water outlet portion H2 is the air passage in the first wash water outlet portion H1 arranged at the throttle air passage inlet 12a. It is made smaller than the cross-sectional area, whereby the air flow velocity V2 in the second wash water spouting portion H2 is made larger than the air flow velocity V1 in the first wash water spouting portion H1, and the second wash water spouting portion is formed. The particle size of the water droplets formed by the atomization accompanying the scattering of the washing water from H2 is made smaller than the particle size of the water droplets formed by the atomization due to the scattering of the cleaning water from the first washing water spraying part H1. Therefore, in the first-stage paint mist collection in the first cleaning zone S1, a relatively large-diameter paint mist is collected by large-sized water droplets, and the second-stage paint mist in the second cleaning zone S2 is collected. Mist collection collects residual paint mist of relatively small diameter by water droplets of small diameter In the so that, it is to ensure that collected coating material mist passing gas A wide mist particle size range.

Further, at such an air flow velocity setting, the noise generated by the paint mist collection in the second stage is larger than the noise generated by the paint mist collection in the first stage. However, also from this, as described above, in order to collect the paint mist in the second stage, the noise generated in the throttle air passage portion on the downstream side of the wall turning portion b is directed to the throttle air passage inlet 12a side. It is effective to reduce the leakage noise to the coating chamber 1 side as a whole by suppressing the leakage of water by the barrier action of the upwardly inclined wall surface a and the downward wall surface c and the sound absorbing action of water droplets in the first cleaning area S1. ..

Of the one side wall 18 of the narrowed air passage 12 (that is, the air passage wall on the side forming the upward inclined wall surface a, the wall surface changing portion b, and the downward wall surface c), the wall surface changing portion b and the downward wall surface The position of the portion 18C forming the c and the position of the portion 18B forming the upward slanted wall surface a are freely adjustable in the direction indicated by the arrow f in the figure, and by this position adjustment, the air flow in the second cleaning water spouting portion H2. The speed V2 and the water droplet particle size in the second cleaning area S2 can be adjusted appropriately according to the operating conditions and the like.

The overflow weir 17 forming the first wash water spouting portion H1 is adjustable in height, and by this height adjustment, washing from the first wash water spouting portion H1 into the narrowed air passage 12 is performed. By adjusting the form of water splash, it is possible to appropriately adjust the state of paint mist collection in the first cleaning area S1.

In the figure, reference numeral 21 designates a downstream side portion 19 of the other side wall 19 in the throttle wind passage 12 which is not received by the upwardly inclined wall surface a and is on the air flow A from the first cleaning area S1.
The collected water W2 of partially scattered water droplets hitting B flows down on the other side wall downstream side portion 19B at a high speed due to the high-speed flow of the gas A, whereas the flowing-down cleaning water W2 is generated in the airflow A in the air duct. It is a step portion that is re-scattered upward in the state accompanied by atomization, and the washing water W1 that flows down from the upward inclined wall surface a
In addition to scattering the water in the wall surface turning portion b as the second wash water spouting portion H2, the wash water W2 that has not reached the upward inclined wall surface a and reaches the other side wall downstream portion 19B is also included in the step portion 21. By re-scattering with, the overall paint mist collecting efficiency is further improved.

The arrangement position of the step portion 21 in the air passage direction on the downstream side portion 19B of the other side wall is determined by which portion the washing water is to be scattered by the step portion 21. The target portion of the cleaning water splashed by the part 21 is set, for example, to a location adjacent to the downstream side or the upstream side of the second cleaning area S2 which is the target portion of the second cleaning water spraying portion H2 for the cleaning water splash. Alternatively, it may be set at a position exiting from the outlet 12b of the throttle wind passage 12, or may be set at the second cleaning area S2 itself, and the second cleaning area S2 may be formed by both the step portion 21 and the wall surface turning portion b. Various settings can be made, such as a configuration in which the second cleaning water spouting portion H2 is configured.

A standing piece 21a is provided at the tip of the step portion 21 to promote the scattering of the cleaning water W2, but this standing piece 21a may be omitted in some cases.

Another Embodiment Next, another embodiment will be described.

In the above-described embodiment, the overflow weir 17 (in other words, the overflow weir provided at the inlet 12a of the restricted air passage 12) to the restricted air passage 12 in the cleaning water tank 10 is used as the first cleaning water for the first cleaning area S1. Although the throwing portion H1 is used, a step portion that scatters the wash water W flowing down along the air passage wall of the squeezing air passage 12 into the first washing area S1 in the state of being atomized is a wind in the middle of the squeezing air passage 12. The concrete structure of the first wash water spouting portion H1 can be modified in various ways, such as being provided on the road wall and using this stepped portion as the first wash water spouting portion H1 for the first wash area S1.

The inclination angle of the upwardly inclined wall surface a and the curvature of the wall surface diverting portion b may be appropriately determined. In some cases, the upwardly inclined wall surface a is not a flat surface, but is convex upward, or For example, a curved surface that is convex downward, or a structure that has a corner instead of the wall surface turning portion b is a curved surface,
The specific structures of the upward inclined wall surface a and the wall surface changing portion b can be modified in various ways.

The angle of the downward wall surface c and the length in the direction of the air passage may be appropriately determined. In some cases, instead of using the downward wall surface c as a flat surface, a downward convex or upward convex curved surface may be used. May be

The cleaning liquid W is not limited to water,
Aqueous solutions of various agents and various liquid agents may be applied.

It should be noted that reference numerals are given in the claims for convenience of comparison with the drawings, but the present invention is not limited to the configurations of the accompanying drawings by the entry.

[Brief description of drawings]

FIG. 1 is a sectional view of a coating booth showing an embodiment.

FIG. 2 is an enlarged cross-sectional view of a throttle air passage showing an embodiment.

FIG. 3 is a sectional view showing a comparative example.

FIG. 4 is a sectional view showing a conventional example.

[Explanation of symbols]

 1 Coating Room 11 Exhaust Chamber 12 Throttling Airway 12a Airway Entrance A Gas W Cleaning Solution S1 Cleaning Area (First Cleaning Area) S2 Second Cleaning Area H1 Liquid Discharging Part (First Liquid Discharging Part) H2 Second Liquid Discharging Gutter part a Inclined wall surface b b Wall surface changing part c Downward wall surface

Claims (1)

[Claims] 1. A throttle air passage (12) for passing a paint mist-containing gas (A) from a coating chamber (1) together with a cleaning liquid (W) at high speed and discharging it to an exhaust chamber (11) is provided, and an air passage inlet ( The cleaning liquid (W) is directed toward a predetermined cleaning area (S1) below the air duct inlet (12a) in the throttle air duct in a state where the air flows downward from the air duct 12a) into the throttle air duct. A paint mist removing device provided with a liquid sparging part (H1) for scattering air, wherein droplets trapping paint mist in passing gas in the cleaning area (S1) are received below the cleaning area (S1). An upper inclined wall surface (a) for guiding the downward flow of the collected droplets of the receiving liquid, and a downward wall surface (c) connected to the lower edge of the upward inclined wall surface (a) are formed in the throttle air passage, The throttle air passage (12) is connected to the front of the upwardly inclined wall surface (a). In the wall surface changing portion (b) between the downward wall surface (c), the airflow in the air passage (A) is arranged to change to the side of the downward wall surface (c), and the wall surface changing portion (b). From the upward inclined wall surface (a) toward the predetermined second cleaning area (S2) below the downward wall surface (c) in the throttled air path in a state accompanied by grain refinement in the air flow in the air path. A paint mist removing device serving as a second liquid spraying section (H2) for a second cleaning area for peeling and scattering the cleaning liquid (W1).