JP2519550B2 - Painting system - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a coating system provided with a facility for collecting waste liquid generated by thinner cleaning, and more particularly to more effective use of reclaimed thinner from the waste liquid.

The present invention is particularly useful in a tunnel-type coating booth for coating an automobile or parts thereof in which an electrostatic coating machine or the like is provided together with a coating color changing device.

(Prior Art) Conventionally, a tunnel-type coating booth for an automobile has a waste liquid (thinner and thinner) generated by cleaning a coating machine with a thinner in the coating process, in addition to an intake collection facility for the paint mist in the coating chamber. It is equipped with a waste liquid recovery device that collects the mixed liquid of paint) from the coating booth and collects it in a tank outside the booth.

This waste liquid recovery apparatus generally comprises a waste liquid tray provided at a proper position in a coating booth and a storage tank communicating with the waste fluid tank outside the coating booth, and collects the waste fluid put in the tray into a tank, and After that, after the necessary treatment is applied to the recovered waste liquid, the treated waste thinner liquid is sent to another process for regeneration treatment such as distillation purification, thereby effectively using the used thinner.

Several proposals have hitherto been made regarding such a waste liquid recovery apparatus. For example, Japanese Examined Patent Publication No. 59-45432 proposes a more efficient and faster waste liquid recovery technique.

(Problems to be explained by the invention) Generally, in the cleaning operation by the thinner, when the color of the paint is changed, the thinner is sent from the manifold with each paint color valve assembled to the pipe to the coater and discharged from the coater. Alternatively, it is performed by discharging from a dump valve of the manifold.

Recently, in order to further enhance the effect of such cleaning, the thinner is divided into several to ten and several times in one cleaning time (paint color changing time), and alternating with air supply at intervals of each several seconds. A cleaning method is adopted in which the product is pressure-fed to a coating machine.

By the way, in recent years, the tendency toward multi-color paints for automobiles has been increasing more and more, and it is not uncommon for paint lines to use paints of about 50 to 70 colors.

Therefore, as the number of paints increases, it is extremely frequent to change the color of the paint in one painting process, and thus the consumption of thinner used for cleaning increases dramatically. Therefore, it has been required to suppress the consumption of the cleaning thinner and to make more effective use thereof.

The present invention has been made to solve such a problem, and it is possible to reduce the consumption of cleaning thinner as a whole without lowering the level of the effect of thinner cleaning.
An object of the present invention is to provide a coating system that includes a waste liquid recovery device and can be advantageously applied to a recent coating facility that performs the above-described multiple washing operations.

(Means for Solving the Problem) The present inventor has conducted repeated studies to achieve such an object,
In the process, for the first of several to ten or more thinner cleanings in one cleaning, in some cases up to a few times from the first, replace the unused thinner with the paint content. It was found that even if some thinner is sent to a painting machine and washed, the effect of thinner washing does not decrease to a level that poses a practical problem. It was confirmed that the waste liquid had the same quality as the thinner liquid obtained by separation such as rough filtration, and thus the present invention was completed.

The present invention comprises a painter, a paint valve for each paint color, an air valve, and a thinner valve assembled on a manifold.When paint is applied, the paint of each color is supplied to the connected painter, and thinner is applied multiple times during washing. Separately, a paint color changing device that is sent to the inside of the manifold and to the coating machine in cooperation with air supply, and a waste liquid discharged from the color changing device by thinner cleaning and discharged from the coating machine are collected and collected. A waste liquid recovery device, a thinner regenerator that separates and collects thinner from the recovered waste liquid, and a regenerated thinner valve are attached to the manifold of the color changing device, and the retransmitted thinner is regenerated from the regenerated device to the regenerated thinner valve. Regeneration thinner supply device for supplying and controlling the operation of the regeneration thinner valve, and among the plurality of times of thinner cleaning at the time of cleaning The first dose or first round and several times subsequent thereto, relates to coating system comprising a control device for Nagareoku playback thinner in the manifold and the sprayer.

 The coater is preferably an electrostatic coater.

The paint color changing device has one manifold or a plurality of manifolds connected to each other, usually both the BOX side and the shortening side manifold, and these manifolds have paint valves of each paint color (usually 10 to 70 colors), An air valve, thinner valve, dump valve, and if necessary, a trigger valve etc. are assembled. This device supplies paint of each color to the painter through a manifold and a paint hose at the time of coating, and at the time of cleaning, the thinner is divided into several to ten or more times, usually in alternation in cooperation with air supply,
Pour into the manifold and into the coater.

The waste liquid recovery device is a device that collects and recovers the waste thinner liquid discharged from the dump valve or the like of the color changing device and discharged from the coating machine by thinner cleaning, for example, a waste liquid receiving tray in a coating booth ( Hopper), waste liquid tank outside the booth, and associated piping equipment.
The technique disclosed in the above Japanese Patent Publication No. 59-45432 may also be referred to.

The thinner regenerator is a device that separates the thinner from the recovered waste liquid, preferably by filtration, and stores the separated thinner in a tank or the like, while discarding the waste liquid having a high solid content or providing it to another process. The regenerated thinner in the tank is supplied to the regenerated thinner valve connected to the paint color changing device by the supply device described below.

The regenerated thinner supply device is a device in which a regenerated thinner valve is assembled to the manifold of the color changing device, preferably to the BOX side manifold, and a thinner supply pipe is connected to the valve from the regenerator via a pump or the like. . The regeneration thinner valve may have the same structure as a normal thinner valve.

Finally, the control device included in the present system controls the operation of the regenerated thinner valve, and controls the valve for the first time of several to ten or more thinner cleanings in the cleaning time when changing the paint color. Activate and pump regenerated thinner into the paint color changer manifold or to the coater. And for the subsequent times, the conventional paint control system controls the operation of the ordinary thinner valve,
Supply unused thinner to a coating machine and wash them. The supply of the regenerated thinner is not limited to the first time and may be performed for the first time and several times after that as long as there is no problem in terms of cleaning effect. Further, the control device may have a single structure or may be incorporated in the coating control system.

(Operation) In the system of the present invention, among several to ten and several times thinner cleaning in the cleaning time at the time of changing the paint color,
For the first round, or for the first round and several subsequent rounds, collect the waste liquid from the previous washing operation, separate the thinner fraction to obtain regenerated thinner, and then for subsequent rounds. In the same manner as before, the paint passage to the inside of the coating machine is cleaned with an unused thinner. Therefore, the amount of cleaning thinner used in the entire system is significantly reduced as compared with the conventional system. Moreover, since the regenerated thinner is used only for the first time, the cleaning action does not decrease as a whole, and the conventional level can be maintained. Therefore, the final evaluation of the cleaning effect is good, and the situation in which the paint of the previous paint color is mixed with the paint of the present paint color does not occur at the beginning of the coating after the color change.

(Example) Hereinafter, the Example of this invention is described with reference to drawings.

The system of the embodiment is applied to a tunnel-type painting booth for automobile painting, and as shown in FIG. 1 schematically, an electrostatic painting machine 1, a paint color changing device 2, a waste liquid collecting device 3,
It consists of a thinner regeneration device 4, a regeneration thinner supply device 5 and a control device 36.

The coating machine 1 is of a general-purpose type, and the bell cup 20 is covered with a cover 19.

The color changing device 2 has a manifold 7 on the shortened side closer to the coating machine.
It is equipped with a, 7c and 7d, and a manifold 7b on the BOX side away from the coating machine.

The manifold 7a is connected to the bell cup 20 of the painting machine 1, and is activated when the paint on the BOX side is sent to the painting machine 1, and the trigger valve 11 that is turned on when the paint on the shortening side is sent to the painting machine 1. D valve 12 is assembled.

The manifold 7c is connected to the T / D valve 12, and is provided with a soft thinner valve 14, a soft air valve 15, and a cup-back thinner valve 16 in addition to a paint valve (not shown) for each paint color. The valves 14 and 15 supply thinner and air from the manifold 7c for cleaning.
12 and operate to feed coating machine 1. The valve 16 is for cleaning thinner by sending thinner to the back side of the bell cup 20 during cleaning.

The manifold 7d is connected to the trigger valve 11, the dump valve 13 is assembled, and the tip thinner valve 17 and the hub thinner valve 18 are assembled. Dump valve 13
Is turned on during cleaning, and sends the waste liquid generated by cleaning by each thinner to the recovery device 3. In addition, valve 17, valve
Reference numeral 18 is for sending thinner to the front surface and the inner side of the bell cup 20 at the time of cleaning to clean those parts.

On the other hand, the manifold 7b on the BOX side is connected to the trigger valve 11, and there are a dozen or more paint valves 8 for each paint color (most valves are omitted in the drawing), an air valve 9, and a thinner valve. 10 and regenerated thinner valve 6 is assembled. As will be described below, these valves 6, 9 and 10 are alternately a thinner and an air at the time of cleaning, and the trigger valves of the manifold 7b to the manifold 7a are alternately arranged at intervals of several seconds.
11, the manifold 7d and the dump valve 13 are supplied to wash the flow path therebetween.

As shown in FIG. 3, the waste liquid recovery device 3 has a waste liquid storage 21
Is formed laterally in the recovery chamber 35 of the coating booth, and the waste liquid discharged from the dump valve 13 passes through the recovery pipe 29 to collect 21
Is stored in. In addition, the waste liquid accumulated inside the cover 19 of the coating machine 1 is also sucked and stored in the reservoir 21 through the recovery pipe 29. Further, the apparatus 3 is provided with the waste liquid hoppers 28, ... on the left and right sides of the lower part of the coating chamber 33 in communication with the reservoir 21 by the pipes 32, ..., and the extra paint discharged from the coating machine 1 in the coating process. (For example, when spraying) is also collected in the reservoir 21 as waste liquid.

In the regenerator 4, a filtration separation tank 22 is installed outside the booth, and the separation tank 22 is provided with a pipe 31 via a pump 30 to collect the waste liquid.
The waste liquid in the reservoir 21 is filtered in the tank 22 by the operation of the pump 30 to separate the thinner content and the high solid content.

The thinner supply device 5 includes a regenerated thinner tank 24 for storing the thinner regenerated by the device 4, a pump 26, and the like. When the pump 26 is operated, the regenerated thinner is supplied to the above-mentioned regenerated thinner valve 6 through the pipe 27 ( (See FIGS. 1 and 3).

On the other hand, the separated high solid content is stored in the waste liquid tank 23, and then the pump 25 is operated to prepare a mixing chamber (not shown).
Sent to.

The final control device 36 controls the operation of the regenerating thinner valve 6 and, for example, as shown in FIG. 2, it is the first of several to ten and several times thinner cleaning in the cleaning time when changing the paint color. For this time, the valve 6 is operated and the regenerated thinner from the tank 24 is flowed out into the manifold 7b of the paint color changing device 2. The controller 36 is incorporated in an automatic painting control system (not shown) equipped on the present painting booth. This control system
Controls all operations of the above-mentioned various valves including each paint valve 8, air valve 9 and thinner valve 10, and at the time of cleaning.
While alternately supplying air and thinner at intervals of 5 seconds to several seconds, unused thinner is supplied to the manifold 7b, the coating machine 1, etc. for the first and subsequent times.

By the operation of the control device 36 and the above control system, the automobile body is automatically painted according to the valve operating procedure shown in the time chart of FIG. 2 at the time of cleaning when the paint color is changed. The waste liquid discharged from the color changing device 2 and discharged from the coating machine 1 was recovered in the reservoir 21, the thinner portion was regenerated in the separation tank 22, and then the thinner valve 6 was supplied. In the system of the example, the amount of thinner used was greatly reduced as compared with the conventional system. In addition, the effect of thinner cleaning could be maintained at the same level as before.

(Effects of the Invention) As described above, according to the present invention, in a coating system that includes a waste liquid recovery device and performs a plurality of thinner supply operations during cleaning, without substantially lowering the level of the effects of thinner cleaning. The consumption of the cleaning thinner can be remarkably reduced in the entire system, and the effect that the thinner can be used more effectively can be obtained. Therefore, this system is very economically advantageous.

[Brief description of drawings]

FIG. 1 is a schematic configuration diagram showing a coating system of an embodiment of the present invention, FIG. 2 is a time chart showing the operation of each valve on the BOX side during cleaning in the system of FIG. 1, and FIG. 3 is a system of the embodiment. It is a figure which shows the inside etc. of the tunnel type coating booth provided with. In the figure, 1 ... Painting machine 2 ... Paint color changing device 3 ... Waste liquid collecting device 4 ... Thinner regenerating device 5 ... Regenerating thinner supplying device 6 ... Regenerating thinner valve 7a, 7b, 7c, 7d ... Manifold 8 …… Paint valve 9 …… Air valve 10 …… Thinner valve

Claims (1)

(57) [Claims] 1. A coating machine and a paint valve, an air valve, and a thinner valve for each coating color are assembled to a manifold, and each color coating material is supplied to the connected coating machine at the time of coating, and a thinner is applied a plurality of times at the time of cleaning. And a paint color changing device that is sent to the inside of the manifold and to the coating machine in cooperation with air supply, and a waste liquid discharged from the color changing device by thinner cleaning and discharged from the coating machine is collected and collected. A waste liquid recovery device, a thinner regenerator that separates and collects thinner from the recovered waste liquid, and a regenerated thinner valve is installed in the manifold of the color changing device, and regenerated thinner is regenerated from the regenerated device by the regenerated thinner valve. And a regeneration thinner supply device for controlling the regeneration thinner valve to control the operation of the regeneration thinner valve so that the thinner cleaning is performed a plurality of times during cleaning. For the first round or first round and several times subsequent thereto, comprising a control device for Nagareoku playback thinner in the manifold and the coater coating system.