JPH10272388A - Color change and cleaning method for multicolor coating equipment - Google Patents

Abstract

PROBLEM TO BE SOLVED: To shorten the entire cleaning time, by completing the cleaning on the upstream side requiring longer cleaning time earlier compared with that on the downstream side from a cleaning valve mechanism interposed between a color change valve device and a coater. SOLUTION: After a coater 3 reaches a coating completing position Pe and the feed of a coating material from a color change valve device 1 is discontinued and before the coater 3 is retracted to a cleaning position Ps, the cleaning of the upstream side 4A of a cleaning valve mechanism 5 is started, and after the coater 3 is moved and retraced to the cleaning position Ps, the cleaning of the downstream side 4B of the cleaning valve mechanism 5 is started. As the cleaning starting time of the upstream side 4A of the cleaning valve mechanism 5 is quickened, the color change cleaning can be completed quicker.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for cleaning a color change of a multi-color coating apparatus for selectively supplying each color paint to a coating machine.

[0002]

2. Description of the Related Art For example, in a multicolor electrostatic coating apparatus for coating an automobile body, the coating color of a preceding color paint for coating a preceding workpiece and a subsequent color paint for coating a subsequent workpiece are different. In such a case, color change cleaning is performed so as not to cause color mixing. In the color change cleaning, the paint supply path from the color change valve device to the electrostatic coating machine is kept in a state where the coating machine is retracted to a predetermined cleaning position where the spray blown from the coating machine does not hit the workpiece. By supplying a cleaning fluid such as a cleaning air and a cleaning thinner, the paint remaining in the color change valve device, the paint supply flow path, and the electrostatic coating machine is removed. In this case, since the automobile body to be coated is placed on the conveyor and conveyed one after another at predetermined intervals, the color change cleaning is performed from the end of the application of the previous color paint to the start of the next color paint. Must be completed within a short time.

By the way, a general multicolor electrostatic coating apparatus is:
In order to reduce the load on painting robots and reciprocators that install electrostatic painting machines, color change valve devices that selectively supply each color paint are installed away from the electrostatic painting machine to supply paint hoses and other paints. Since the flow path is long, it takes time to cleanly remove the paint remaining in the color changing valve device and the long paint supply flow path.

For this reason, conventionally, as shown in FIG.
A cleaning valve mechanism 5 is interposed in the paint supply path 4 from the color changing valve device 1 for selectively supplying each color paint to the electrostatic coating machine 3 via the fixed-quantity supply means 2 near the coating machine 3. A mechanism 5 moves the paint supply flow path 4 to its upstream side 4
A and a multi-color electrostatic coating apparatus divided into a downstream side 4B have been proposed (JP-A-61-46271). According to this multicolor electrostatic coating apparatus, when performing color change cleaning, the cleaning air supplied from the color change valve apparatus 1 and the cleaning thinner upstream from the color change valve apparatus 1 to the cleaning valve mechanism 5. The side 4A is cleaned, and the waste liquid is discharged from the cleaning valve mechanism 5 to the waste liquid tank 6. At the same time, the cleaning air supplied from the cleaning valve mechanism 5, the cleaning thinner, and the downstream side 4 </ b> B from the cleaning valve mechanism 5 to the electrostatic coating machine 3.
Make sure to wash. As described above, since the long paint supply flow path 4 can be divided into the upstream side 4A and the downstream side 4B and can be individually and simultaneously cleaned, the color change cleaning time can be reduced.

[0005]

However, recently, in order to improve the production efficiency, it has been desired to further shorten the cleaning time. And according to the experiment of the inventor,
Although the downstream side 4B of the cleaning valve mechanism 5 can be cleaned in a relatively short time, the upstream side 4A of the cleaning valve mechanism 5 is compared with the cleaning because the color changing valve device 1 having a complicated flow path formed therein is connected. It turns out that it takes a long time.

Accordingly, an object of the present invention is to shorten the entire cleaning time by terminating the cleaning on the upstream side of the cleaning valve mechanism earlier.

[0007]

In order to solve this problem, the present invention relates to a color change valve device which is provided in a paint supply passage from a color change valve device for selectively supplying each color paint and a cleaning fluid to a coating machine. / Trigger valve for switching and supplying each color paint or cleaning fluid sent from the washing machine to the coating machine or the waste liquid tank, and washing for sending the cleaning fluid sent from the washing fluid supply source to the coating machine. In the color changing cleaning method for a multicolor coating apparatus in which a cleaning valve mechanism provided with a fluid supply valve is interposed and the paint supply flow path is divided into an upstream side and a downstream side by the cleaning valve mechanism, The coating machine that has been painting the object to be sprayed by spraying the paint supplied from the valve device reaches the coating end position of the object to be coated, and the supply of the paint from the color changing valve device to the coating device stops. After that, the coating machine Before retreating to a predetermined cleaning position, the cleaning fluid is supplied from the color changing valve device, and the waste liquid is discharged from a trigger / dump valve of the cleaning valve mechanism to a waste liquid tank. After the cleaning is started and the coating machine retreats to a predetermined cleaning position set in advance, a cleaning fluid supply valve of the cleaning valve mechanism is opened to supply a cleaning fluid to the coating machine, and a cleaning valve mechanism is provided. The washing on the downstream side of is started.

According to the present invention, after the painting machine reaches the painting end position and the supply of the paint from the color changing valve device is stopped, before the painting machine retreats to the washing position, the upstream of the washing valve mechanism is provided. Start cleaning the side. That is, by operating the trigger / dump valve of the cleaning valve mechanism interposed in the paint supply flow path from the color changing valve device to the coating machine, the upstream side of the cleaning valve mechanism is communicated with the waste liquid tank, and the color changing valve device is operated. When the cleaning fluid is supplied from the printer, the cleaning fluid is discharged from the color changing valve device to the waste liquid tank via the trigger / dump valve of the cleaning supply valve mechanism. As a result, the inside of the flow path from the color changing valve device to the cleaning valve mechanism is cleaned, and at this time, all the waste liquid is collected in the waste liquid tank and is not jetted from the coating machine, so that the object to be coated may be sprayed. Absent.

Next, after the coating machine moves and retreats to a cleaning position where the object is not splashed, cleaning of the downstream side of the cleaning valve mechanism is started. That is, when the cleaning fluid supply valve of the cleaning valve mechanism is opened to supply the cleaning fluid to the coating machine, the waste liquid is ejected from the coating machine and discharged, and the downstream side of the cleaning valve is cleaned. in this way,
After the painting machine reaches the painting end position and the supply of paint is stopped, before the painting machine retreats to the washing position, starts washing on the upstream side where the color changing valve device, which requires a long time for washing, is connected. As a result, the time required for the coating machine to move from the painting end position to the washing position is effectively used, and the end time of the color change washing can be shortened.

[0010]

Embodiments of the present invention will be specifically described below with reference to the drawings. FIG. 1 is a timing chart showing the method of the present invention.

[0011] The multicolor coating apparatus used in the method of the present invention includes:
An electrostatic coating machine (coating machine) from a color changing valve device 1 for selectively supplying each color paint, a cleaning air (cleaning fluid), and a cleaning solvent (cleaning fluid) via a quantitative supply means 2 such as an air operated regulator or a flashable gear pump. A cleaning valve mechanism 5 is interposed in the paint supply flow path 4 leading to 3, and the paint supply flow path 4 is divided into an upstream side 4A and a downstream side 4B by the cleaning valve mechanism 5. The color changing valve device 1 includes color changing valves V, V... Connected to each color paint supply source, a cleaning air supply valve Va and a cleaning thinner supply valve Vc connected to the cleaning air supply source and the cleaning thinner supply source. ing. The cleaning valve mechanism 5 is provided with the color changing valve device 1.
Each color paint fed from the cleaning air, a trigger / dump valve V _T for switching換送feeding the cleaning solvent sprayer 3 or waste liquid tank 6, connected wash air to the wash air supply source and the washing thinner supply source Supply valve (cleaning fluid supply valve)
V _E and washing thinner supply valve (cleaning fluid supply valves)
_VL . The trigger / dump valve _VT is
A trigger valve 8 for connecting the upstream side 4A to the downstream side 4B at the time of painting, and connecting the upstream side 4A to a waste liquid passage 7 connected to the waste liquid tank 6 at other times, and a dump valve interposed in the waste liquid passage 7 And a valve 9.

Next, the case of performing the color change cleaning according to the method of the present invention will be described. For example, when painting the side surface of the automobile body W, first, the electrostatic painting machine 3 is made to stand by at the painting start position Ps (T ₁ ), and when the automobile body W arrives, a high voltage is applied. while reciprocated up and down in state are relatively moved toward the rear of the automobile body W to painting end position Pe (T ₁ ~T _2). During this time, color change valve device 1 opens to any color change valve V for supplying a desired color of paint, cleaning valve mechanism 5 is communicated with the upstream side 4A and a downstream side 4B by the trigger / dump valve V _T,
Wash air supply valve V _E and washed thinner supply valve V _L
Is closed. Thereby, the paint supplied from the color changing valve device 1 is sprayed from the electrostatic coating machine 3 to perform the painting.

Next, when the electrostatic painting machine 3 reaches the painting end position, the application of the high voltage to the painting machine 3 is stopped, and the color changing valve V, which has supplied the paint, is closed to change the color. supply of coating material from the valve device 1 is stopped, the coater 3 starts moving toward the coating start position 3 (T ₂ through T
₃ ) At the same time, cleaning of the upstream side 4A from the color changing valve device 1 to the cleaning valve mechanism 5 is started. Specifically, first, by operating the trigger / dump valve V _T of the cleaning valve mechanism 5, thereby blocking the upstream 4A and the downstream side 4B by the trigger valve 8, by opening the dump valve 9,
The waste liquid flow path 7 from the upstream side 4A to the waste liquid tank 6 is conducted. When the cleaning air supply valve Va and the cleaning thinner supply valve Vc of the color changing valve device 1 are alternately opened to supply the cleaning air and the cleaning thinner intermittently, the coating machine 3 moves from the coating end position Pe to the coating start position Ps. 4A, the upstream side 4A from the color changing valve device 1 to the cleaning valve mechanism 5
The inside is cleaned. At this time, all the waste liquid is collected in the waste liquid tank and is not ejected from the coating machine 3, so that even if the coating machine 3 is directly facing the vehicle body W, the waste liquid does not splash on the vehicle body W.

Next, after the electrostatic coating machine 3 retreats to the coating start position (cleaning position) Ps, the downstream side 4B from the cleaning valve mechanism 5 to the coating machine 3 is cleaned. In particular,
With the atomizing head of the coating machine 3 facing the inside of the shroud (not shown), the cleaning air supply valve V of the cleaning valve mechanism 5 is set.
_E and the cleaning thinner supply valve _VL are alternately opened to supply the cleaning air and the cleaning thinner intermittently, so that the inside of the downstream side 4B from the cleaning valve mechanism 5 to the electrostatic coating machine 3 is cleaned. ejected from the coating machine 3 is collected in the shroud (T ₃ through T ₄₎

[0015] When the cleaning of both the upstream side 4A and the downstream side 4B is completed, the coating machine 3 is made to wait at the coating start position Ps, and when the following automobile body W arrives, the coating is performed with the next color paint. (T ₅ ).

That is, when the electrostatic spraying machine 3 reaches the painting end position Pe and the paint spraying is finished, the coating machine 3
Before retreating to the coating start position Ps, which is the washing position,
Since the cleaning of the upstream side 4A to which the color changing valve device 1 requiring a long time for cleaning is started is started, the time required for the electrostatic coating machine 3 to move from the coating end position to the cleaning position is effectively saved. It can be used, and the end time of the color change cleaning can be hastened. Further, since the downstream side 4B of the cleaning valve mechanism 5, which requires a relatively short cleaning time, starts cleaning when the electrostatic coating machine 3 retreats to the coating start position Ps, which is the cleaning position, the automobile body W There is no splash on the surface.
In the above description, a case is described in which a multicolor electrostatic coating apparatus including the electrostatic coating machine 3 is used. However, the present invention is not limited to this, and a multicolor electrostatic coating apparatus including a non-electrostatic coating machine such as air atomization is used. Needless to say, the present invention can be applied to a color coating apparatus.

[0017]

As described above, according to the present invention, the cleaning start timing on the upstream side of the cleaning valve mechanism to which the color changing valve device requiring a long time for cleaning is connected, and the cleaning time are relatively short. The cleaning start timing on the downstream side of the cleaning valve mechanism is shifted, and the timing on the upstream side of the cleaning valve mechanism is set so that cleaning starts when the coating machine reaches the coating end position and the supply of the paint ends. The color change cleaning can be completed early because it hastened, and at the same time, the downstream of the cleaning valve mechanism starts cleaning when the coating machine retreats to the cleaning position, so the cleaning blown out from the coating machine This is a very excellent effect that the fluid droplets do not adhere to the object to be coated.

[Brief description of the drawings]

FIG. 1 is a timing chart showing the method of the present invention.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Color change valve apparatus 2 ... Quantitative supply means 3 ... Electrostatic coating machine (coating machine) 4 ... Paint supply flow path 4A ... ... upstream 4B · · · · · downstream 5 ...... flush valve mechanism 6 ...... waste tank V _T · · · · · trigger / dump valve V _E · · · · · Cleaning air supply valve (cleaning fluid supply valve) _VL ... Cleaning thinner supply valve (cleaning fluid supply valve) W ... Car body (substrate)

Claims (1)

[Claims] 1. A color supply valve (1) for selectively supplying each color paint and a cleaning fluid to a paint supply passage (4) from a color change valve device (1) to a coating machine (3). Trigger / dump valve (V _T ) for switching and supplying each color paint or cleaning fluid to the coating machine (3) or the waste liquid tank (6).
And a cleaning fluid supply valve (V _E ) for supplying a cleaning fluid supplied from a cleaning fluid supply source to the coating machine (3).
V _L ), a cleaning valve mechanism (5) is interposed, and the cleaning valve mechanism (5) is used for the paint supply flow path (4).
Is a method for cleaning a color change of a multi-color coating apparatus divided into an upstream side (4A) and a downstream side (4B). ) Reaches the coating end position of the object to be coated (W), and the supply of the paint from the color changing valve device (1) to the coating machine (3) is stopped. After that, before the coating machine (3) retreats to a predetermined cleaning position, the cleaning fluid is supplied from the color changing valve device (1) and the waste liquid is supplied to the trigger / dump valve of the cleaning valve mechanism (5). (V _T ) to the waste liquid tank (6) to start the cleaning of the upstream side (4A) of the cleaning valve mechanism (5), and the coating machine (3) is set to a predetermined cleaning position. After the evacuation, the cleaning fluid supply valves (V _E , V _L ) of the cleaning valve mechanism (5) are opened and The cleaning fluid is supplied to the coating machine (3), and the downstream side (4B) of the cleaning valve mechanism (5).
Cleaning method for a multicolor coating apparatus, characterized by starting the cleaning of a multicolor coating apparatus.