JPH0621571Y2 - Multicolor painting equipment - Google Patents

Description

[Detailed Description of the Invention] [Industrial field of application] The present invention relates to a multicolor coating apparatus for coating each color paint by changing its color, and in particular, a diaphragm pump or the like as a pump for quantitatively supplying each color paint to a coating machine. Relates to a multi-color coating device using a double-acting reciprocating pump.

[Conventional technology]

If a double-acting reciprocating pump such as a diaphragm pump that pressurizes the paint at a predetermined flow rate according to the flow rate of the working fluid is used as a pump for quantitatively supplying the paint to the coating machine, the flow rate of the working fluid can be measured and controlled. Since the flow rate of the paint can be controlled, and there is no need to directly measure the flow rate of the paint, there is an advantage that the trouble of the flow meter, which was a problem when using high-viscosity paint, is eliminated. (See Japanese Patent Laid-Open No. 62-170166).

Also, if this reciprocating pump is applied to a multicolor coating device, the trouble of controlling the number of revolutions for each pump is eliminated, as in the case where a fixed amount of each color paint is supplied by a rotary pump such as a gear pump. There is an advantage that a very simple control is sufficient by switching the flow path of the working fluid controlled to a predetermined flow rate according to the amount and selectively supplying this to each reciprocating pump.

[Problems to be solved by the device]

By the way, in a multi-color painting device that changes the color of each color and paints, the color change time from the end of painting the previous color paint to the start of painting the next color paint is about 10 seconds. It is desired to be short.

Therefore, at the same time when the washing of the previous color paint remaining in the paint machine or the paint tube connected between this and the color change valve device is completed, the next color paint is immediately filled in the tube and the paint machine. There is a need.

For that purpose, when filling the coating machine with the next color paint, the flow rate of the working fluid supplied to the reciprocating pump is increased more than at the time of coating, and the next color paint is pressed out at a large flow rate. In this case, the rotation of the metering rotary pump, which supplies the working fluid in a fixed amount from the working fluid supply source, must be remarkably increased in rotation temporarily. The change in the discharge amount that deteriorates the quantitativeness occurs early.

In addition, even if the rotation speed of the metering rotary pump is increased to increase the flow rate of the working fluid supplied to the reciprocating pump, if the flow rate of the paint supplied to the reciprocating pump is as small as that at the time of coating, the reciprocating pump Since the working fluid presses out the paint before a sufficient amount of the paint is filled, the pressure of the working fluid rises abnormally and the pressure switch for stopping the rotary metering pump operates.

In a multicolor coating device, it is necessary to constantly circulate unpainted paint to prevent its precipitation, but this cannot be done only with a rotary metering pump.

Therefore, the present invention constantly circulates unpainted paint to prevent its precipitation, and utilizes its circulation mechanism,
It is a technical issue to be able to fill the next color paint into the coating machine that has completed the cleaning of the previous color paint in an extremely short time.

[Means for Solving the Problem] In order to solve this problem, according to the present invention, each color paint which is pressure-fed and supplied from a paint supply source to each double-acting reciprocating pump through a paint supply pipe operates from a working fluid supply source. Through the fluid supply pipe, the reciprocating pump is squeezed out at a predetermined flow rate according to the flow rate of the working fluid that is supplied and supplied to each color change valve, and the paint of a specific color selected by switching of each color change valve In a multicolor coating device configured to be supplied in a fixed amount to a coating machine, each of the reciprocating pumps is a metering rotary pump for pumping a working fluid from a working fluid supply source at a flow rate according to a paint discharge amount of the coating machine. Directional control is provided for the first working fluid supply pipe provided and for the second working fluid supply pipe provided with a rotary rotary pump for circulating a working fluid for circulating the paint not supplied to the coating machine. Each pipe that is switchably connected via a control valve and that connects between the directional control valve and the second working fluid supply pipe is connected to the coating machine that has finished cleaning the previous color paint and the next color paint. Is provided with a flow rate adjusting valve for increasing the flow rate of the working fluid supplied to the reciprocating pump for filling the same as that during the paint circulation, and
Each of the paint supply pipes is also provided with a flow rate adjusting valve for increasing the flow rate of the next-color paint supplied to the reciprocating pump for filling the next-color paint in the coating machine, compared with the case of painting and the time of paint circulation. It is characterized by being.

[Action]

According to the present invention, by switching the directional control valve, the reciprocating pump that supplies a fixed amount of paint to the coating machine is supplied with the working fluid that is pumped by the rotary metering pump, and the other fluid that does not supply the coating machine to the coating machine. The reciprocating pump is supplied with a working fluid that is pumped by a circulating rotary pump to prevent the paint from settling.

When changing the color of the paint, the double-acting reciprocating pump that fills the painter with the next color paint into the painting machine that has finished washing the previous color paint, rather than when painting and circulating the paint through the paint supply pipe. A large amount of paint is pumped and supplied, and a larger amount of working fluid is pumped and supplied through the second working fluid supply pipe equipped with a rotary pump for circulation than when the paint is circulated. It is smoothly squeezed out and the coating machine is instantly filled.

Further, according to the present invention, it is not necessary to increase the number of rotations of the measuring rotary pump at the time of filling the next color paint, so that the fluctuation of the paint discharge amount due to the leakage or wear of the shaft sealing portion of the rotary pump occurs at an early stage. Nothing.

Further, the working fluid pressure-fed from the circulation rotary pump to each reciprocating pump is always maintained at a flow rate suitable for paint circulation, and is temporarily set to a flow rate higher than that during paint circulation only during paint filling. The damage of each reciprocating pump is very small.

〔Example〕

Hereinafter, embodiments of the present invention will be specifically described with reference to the drawings.

FIG. 1 is a flow sheet diagram showing an example of a multicolor coating apparatus according to the present invention, and FIG. 2 is a time chart showing its operation.

In this example, the next-color paint which is pressure-fed and supplied from the paint supply sources to the double-acting reciprocating pumps 3a and 3b through the paint supply pipes 2a and 2b connected to the paint circulation outward pipes 1a and 1b, respectively,
Reciprocating pumps 3 a, 3 from the working fluid supply source 4 through the first working fluid supply pipe 5 or the second working fluid supply pipe 6.
It is designed to be squeezed out at a predetermined flow rate according to the flow rate of the working fluid that is pumped and supplied to b, and to be supplied to each color change valve 7a, 7b.

Each of the reciprocating pumps 3a, 3b has a first working fluid supply pipe 5
And a manifold 8 for the second working fluid supply pipe 6.
It is configured to be switchably connected to each other via directional control valves 9a and 9b.

The first working fluid supply pipe 5 is provided with a metering rotary pump 11 for pumping the working fluid from the working fluid supply source 4 at a flow rate corresponding to the amount of paint discharged from the coating machine 10, and a filter 12, and The second working fluid supply pipe 6 is provided with a coating machine 10
A circulating rotary pump 13 for pressure-feeding a working fluid for circulating paint not supplied to the filter, and a filter 14 are provided.

Then, the second working fluid supply pipe 6 and the directional control valve 9
The reciprocating pumps 3a or 3b for filling the next color paint into the coating machine 10 which has completed the washing of the previous color paint are supplied to the pipes 15a and 15b respectively connecting between the a and 9b. Flow rate adjusting valves 16a and 16b are respectively provided to increase the flow rate of the working fluid by a certain amount or more than when the paint is circulated.

In addition, the flow rate of the next color paint supplied to the reciprocating pumps 3a or 3b for filling the paint supply pipes 2a and 2b with the next color paint in the painting machine 10 after the washing of the previous color paint is completed. Flow rate adjusting valves 17a and 17b are provided to increase the flow rate by a certain amount or more than during painting and circulating paint.

The manifold 8 has a first working fluid supply pipe 5
A directional control valve 18 is provided to switch the flow path of the working fluid pressure-fed by the rotary metering pump 11 from the inside of the manifold 8 to the working fluid supply source 4 side.
When both a and 3b circulate the paint, the working fluid supply pipe 5 is connected to the working fluid supply source 4 via the direction control valve 18.
It is adapted to be connected to a return pipe 19 leading to the.

Further, the rotary metering pump 11 rotates its motor 21 based on the pressure detection signal of the pressure switch 20 which detects the pressure fluctuation of the working fluid pumped by the pump.
The inverter 22 is variably controlled according to the paint discharge amount of zero.

On the other hand, the motor 23 of the circulation rotary pump 13 is set to a constant rotation speed capable of pumping the working fluid at a flow rate higher than that required for circulating the paint.

Next, the color change valves 7a and 7b are connected to the reciprocating pumps 3a and 3b.
Direction control valve that switches the flow path of the paint supplied from b to the paint circulation return pipes 24a, 24b side communicating with the supply source of each color paint and the inside of the manifold 26 communicating with the paint hose 25 connected to the coating machine 10. It has become.

In addition, the manifold 26 provided with the color changing valves 7a and 7b has a cleaning solvent supply valve 2 including an on / off valve.
7 and a cleaning air supply valve 28 are attached.

Note that V _{1 to} V ₁₁ are the flow rate adjusting valves 16a, 16b and 1
7a, 17b, directional control valves 9a, 9b and 18, color change valves 7a and 7b, cleaning solvent supply valve 27, and cleaning air supply valve 28 are interface valves that output air signals for sequence control.

Further, R ₁ and R ₂ are an air pressure signal for setting the flow rate of the working fluid pumped by the circulation rotary pump 13 to a flow rate suitable for filling the paint, and an air pressure signal for setting a flow rate suitable for the circulation of the paint. Is a pressure controller which outputs to the flow rate adjusting valves 16a and 16b, respectively.

Further, R ₃ and R ₄ are an air pressure signal for setting the flow rate of each color paint pumped through each paint supply pipe 2a, 2b to a flow rate suitable for filling the paint, and an air pressure signal for setting a flow rate suitable for coating. Is a pressure controller that outputs to the flow rate adjusting valves 17a and 17b, respectively.

Further, R ₅ is a pressure controller for controlling the air pressure of the pilot air supplied to the direction control valves 9a, 9b and 18 and the color change valves 7a, 7b to a constant value, and R ₆ is the cleaning air supply valve 28. It is a pressure controller that controls the air pressure of the cleaning air supplied to the chamber to a constant level.

Further, 29 is a working fluid discharge pipe for returning to the working fluid supply source 4 the working fluid squeezed out from each pump by the paint supplied to each reciprocating pump 3a, 3b.

Before starting painting, as shown in Fig. 1,
The air pressure signal output from the pressure controller R ₄ is the valve V ₆ ,
Each reciprocating pump 3 is inputted through V ₇ to the flow rate adjusting valves 17a, 17b provided in the paint supply pipes 2a, 2b.
The flow rate of the paint supplied to a and 3b is set to the same flow rate as that at the time of coating.

In addition, the reciprocating pumps 3a and 3b are respectively connected to the manifold 8
Is connected to the second working fluid supply pipe 6 via the directional control valves 9a and 9b provided in the flow control valve, and the air pressure signal output from the pressure controller R ₂ is supplied to the flow control valve through the valves V ₁ and V _2. Each reciprocating pump 3 is input to 16a and 16b.
The flow rate of the working fluid supplied to the a and 3b is set to a flow rate at which the paint supplied to the reciprocating pumps 3a and 3b is squeezed out and circulated at the same flow rate as at the time of coating.

At this time, the rotary metering pump 11 provided in the first working fluid supply pipe 5 supplies the working fluid from the pipe 5 through the return pipe 19 at a predetermined flow rate according to the amount of paint discharged from the coating machine 10. It is circulated in the path returning to the working fluid supply source 4.

In addition, each color change valve 7 provided in the manifold 26
Reference numerals a and 7b respectively connect the flow paths of the paint pressure-fed from the reciprocating pumps 3a and 3b to the paint circulation return pipes 24a and 24b, respectively.

As a result, the paint that is pressure-fed and supplied to the reciprocating pumps 3a and 3b is constantly circulated at the same flow rate as at the time of coating, and the precipitation of the paint is reliably prevented.

Next, in this state, when coating is performed using, for example, red paint supplied to the reciprocating pump 3a, the valves V ₁ , V ₆ and V ₈ are switched (T _{1 in} FIG. 2) to control the pressure. Bowl R
₁ outputs an air pressure signal to the flow rate adjusting valve 16a to make the flow rate of the working fluid larger than that at the time of paint circulation, and the pressure controller R ₃ supplies the flow rate of the paint to the flow rate adjusting valve 17a at the time of coating and paint. An air pressure signal that makes the pressure higher than during circulation is output, and at the same time, the color change valve 7a switches to the coating machine 10 side.

As a result, the red paint supplied to the reciprocating pump 3a becomes
A large flow rate is squeezed out from the pump, and the interior of the coating machine 10 is instantly filled.

When the filling of the paint is completed in this way, the valves V ₁ , V ₆ and V ₈ are returned to their original state (T _{2 in} FIG. ₂ ),
Then, by the switching of the valve V _3, V ₄ and V _8, pilot air supplied from the valves, the directional control valve 18 and 9a provided on the manifold 8, the switching of the color changing valve 7a is performed ( Figure 2 _T 3).

As a result, the working fluid pressure-fed by the metering rotary pump 11 provided in the first working fluid supply pipe 5 at a predetermined flow rate according to the amount of paint discharged from the coating machine 10 is the directional control valve 18-the manifold 8. The red paint, which is supplied to the reciprocating pump 3a through the direction control valve 9a and is squeezed out of the reciprocating pump 3a by the working fluid, is discharged from the coating machine 10 at a predetermined discharge amount.

The valve V ₃ is designed to be switched in conjunction with turning on / off of the coating machine 10. When the coating machine 10 is turned off midway, the directional control valve 18 returns to the first working fluid supply pipe 5. Switched to pipe 19.

When the red paint is finished in this way, the valve V
₃ , V ₄ and V ₈ return to the original state shown in FIG.
T ₄ ), the red paint supplied from the paint circulation forward pipe 1a to the reciprocating pump 3a through the paint supply pipe 2a is squeezed out by the working fluid supplied through the second working fluid supply pipe 6 and the paint circulation return pipe The circulation will be restarted on the path from 24a to the paint supply source.

Next, this time, the valves V ₁₀ and V ₁₁ are switched alternately and intermittently (T _{5 to} T _{6 in} FIG. 2), and the cleaning solvent supplied from the cleaning solvent supply valve 27 and the cleaning air supply valve 28 and the cleaning solvent are supplied. By the air, the red paint remaining in the manifold 26, the paint hose 25, and the coating machine 10 is washed away.

Then, when the washing of the red paint, which is the previous color paint, is completed,
The valves V ₂ , V ₇ and V ₉ are switched (T _{7 in} FIG. 2), and an air pressure signal for increasing the flow rate of the working fluid to the flow rate adjusting valve 16b is output from the pressure controller R ₁ to the flow rate adjusting valve 16b. At the same time, the pressure regulator R _{3 is connected} to the flow rate control valve 1
An air pressure signal for increasing the flow rate of the paint to 7b is output to increase the flow rate of the paint than during painting and circulation of the paint.

Thereby, for example, the white paint supplied to the reciprocating pump 3b is squeezed out from the pump at a large flow rate, and the coating machine 1
It is filled up to 0 instantly.

This way, the complete filling of the white paint as the next color paint, the valves _V 2, _{V 7} and _{V 9} returns to its original state (FIG. 2 _T 8), then, the valve _V 3, _{V 5} And V ₉ by switching the pilot air supplied from the respective valves to the directional control valves 18 and 9b provided in the manifold 8,
The color change valve 7b is switched (T _{9 in} FIG. 2).

As a result, the working fluid pressure-fed by the metering rotary pump 11 provided in the first working fluid supply pipe 5 at a predetermined flow rate according to the amount of paint discharged from the coating machine 10 is the directional control valve 18-the manifold 8. The white paint that is supplied to the reciprocating pump 3b through the direction control valve 9b and is squeezed out of the reciprocating pump 3b by the working fluid is discharged from the coating machine 10 at a predetermined discharge amount.

[Effect of device]

As described above, according to the present invention, the double-acting reciprocating pump for supplying the coating material in a fixed amount to the coating machine is provided with the first working fluid supply pipe provided with the metering rotary pump and the circulating rotary pump. Since it is switched and connected to the second working fluid supply pipe, unpainted paint can be constantly circulated to prevent its precipitation, and the flow rate of the working fluid supplied to the reciprocating pump can be reduced. Since the rotation speed of the metering rotary pump does not have to be increased in order to fill the coating machine with paint in a short time, the amount of paint discharge fluctuates due to leakage or wear of the shaft sealing part of the metering rotary pump. It has a very excellent effect that it is possible to surely prevent an adverse effect that occurs at an early stage.

In addition, the working fluid that is pressure-fed and supplied from the circulation rotary pump to each reciprocating pump is always maintained at a flow rate suitable for paint circulation, and is temporarily set to a flow rate higher than that during paint circulation only during paint filling. There is also an effect that the damage of each reciprocating pump is very small.

[Brief description of drawings]

FIG. 1 is a flow sheet diagram showing an example of a multicolor coating apparatus according to the present invention, and FIG. 2 is a time chart showing its operation. Explanation of symbols 2a, 2b ... Paint supply pipe, 3a, 3b ... Double-acting reciprocating pump, 4 ... Working fluid supply source, 5 ... First working fluid supply pipe, 6 ... Second working fluid Supply piping, 7a, 7
b ... Color change valve, 9a, 9b ... Direction control valve, 10 ...
… Coating machine, 11 …… Rotary pump for metering, 13 …… Rotary pump for circulation, 15a, 15b …… Pipes, 16a, 16b
...... Flow rate adjusting valves, 17a, 17b ...... Flow rate adjusting valves.

Claims (1)

[Scope of utility model registration request] 1. Color paints which are pressure-fed from the paint supply source to the double-acting reciprocating pumps (3a), (3b) through the paint supply pipes (2a), (2b) are supplied from the working fluid supply source (4). Each reciprocating pump (3a) through the working fluid supply pipe, (3b) is supplied to each color change valve (7a), (7b) is squeezed out at a predetermined flow rate according to the flow rate of the working fluid that is pumped and supplied to the reciprocating pumps (3a), (3b), Each color change valve (7a),
The paint of the specific color selected by switching (7b)
In the multicolor coating device configured to be supplied in a constant amount to (0), each of the reciprocating pumps (3a), (3b) is a working fluid supply source (4).
Supply to the first working fluid supply pipe (5) provided with a rotary metering pump (11) for pumping the working fluid at a flow rate according to the paint discharge amount of the coating machine (10) and the coating machine (10) Circulating rotary pump that pumps working fluid to circulate unpainted paint
For the second working fluid supply pipe (6) provided with (13),
The directional control valves (9a) and (9b) are switchably connected to each other, and each of the directional control valves (9a) and (9b) is connected to the second working fluid supply pipe (6). Reciprocating pumps (3a), (3b), (16b) that fill the pipes (15a), (15b) with the next-color paint when the painter (10) that has finished cleaning the previous-color paint is filled. The paint supply pipes (2a) and (2b) are also provided with reciprocating pumps (3a) and (3b) that fill the painter (10) with the next color paint. A multicolor coating device characterized in that it is provided with flow rate adjusting valves (17a), (17b) for increasing the flow rate of the next-color paint to be applied during painting and circulating the paint.