JPH0871485A - Paint circulating feeder - Google Patents

Abstract

PURPOSE: To easily heat or cool a paint and to control the temp. even with a small-sized heat exchanger by repeatedly introducing a part of the paint flowing in a paint feeding and circulating line into a paint temp. controlling circulating line to heat or cool the paint. CONSTITUTION: A coater 6 is connected to the paint feed pipe 2 and paint return pipe 3 through which a paint is circulated with a paint feed hose 4 and a paint return hose 5 to constitute a paint feeding and circulating line S. In this paint circulating feeder, a part of the paint flowing in the line S is drawn off, heated or cooled and then returned to the line S through a paint temp. controlling circulating line H, the line H is provided with a circulating pump 9 and a heat exchanger 10, an outlet Hb to return the paint to the line S is connected to the paint feed pipe 2, and an inlet Ha to introduce the paint from the line S is connected to the line S except the passage extending from the outlet Hb to the coater 6.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paint circulating and supplying device for circulating and supplying paint to a coating machine in order to prevent the paint from settling in a paint pipe.

[0002]

2. Description of the Related Art In a paint circulating and supplying device of this type, as shown in FIG. 3, a paint tank 1 is connected with a paint forward pipe 2 and a paint return pipe 3, and the paint forward pipe 2 and the paint return pipe 3 are connected. To the coating machine 6 via the paint supply hose 4 and the paint recirculation hose 5.
Are connected to form a paint supply circulation system S.

Therefore, when the pressure pump 7 is started, the paint tank 1
The paint inside flows from the paint forward pipe 2 into the paint supply hose 4, the paint return hose 5, and the paint return pipe 3 and returns to the paint tank 1 again, so that the paint does not settle in each pipe. A heat exchanger 31 that heats or cools the paint is arranged on the upstream side of the paint forward pipe 2, so that the paint temperature and thus the paint viscosity can be maintained constant throughout the year regardless of changes in temperature. It is designed to provide uniform coating quality.

[0004]

However, in the paint supply circulation system S, a sufficient amount of paint (for example, every minute) is applied so that the flow rate of the paint sprayed from each coating machine does not become insufficient or the spray pressure does not decrease. 30 liters) is circulated and only a part of it (for example, 3 liters per minute) is sprayed from the coating machine, but in order to maintain a constant temperature of the paint sprayed from the coating machine. Therefore, all the paint that is circulated and supplied to the paint supply circulation system S must be heated / cooled to a predetermined temperature by passing through the heat exchanger 31 only once. There was a problem that the installation space wasted.

That is, although most of the paint that is circulated and supplied is not discharged from the coating machine 6 and is returned to the paint tank 1, all of this paint is heated / cooled. Most of the cooled paint is mixed with a large amount of paint in the paint tank again, heat is taken when the paint is heated, and it is heated when the paint is cooled. Therefore, a large heat exchanger 31 is used. The thermal efficiency is very low in spite of the fact. Therefore, it is a technical object of the present invention to efficiently heat or cool the paint by using a small heat exchanger so that the paint supplied to the coating machine can be adjusted to an appropriate temperature.

[0006]

In order to solve this problem, according to the present invention, a coating machine is connected to a paint forward pipe and a paint return pipe through which paint is circulated via a paint supply hose and a paint reflux hose. In a paint circulating and supplying device having a paint supplying circulating system, a paint temperature adjusting circulating system for taking out a part of the paint flowing through the paint supplying circulating system, heating or cooling it, and returning it to the paint supplying circulating system again. The paint temperature adjusting circulation system is provided with a temperature adjusting circulation pump and a heat exchanger, and the paint supply hose has an outlet for returning the paint to the paint supplying circulation system. Alternatively, it is connected to the paint forward pipe, and the inlet for taking in the paint from the paint supply circulation system is connected to the paint supply circulation system excluding the flow path from the flow outlet to the coating machine. To do.

[0007]

According to the present invention, by circulating the coating material in the coating material temperature control circulation system, the coating material passes through the heat exchanger many times and is adjusted to a temperature higher or lower than the optimum temperature. At this time, a part of the paint flowing through the paint supply circulation system is taken out and the temperature is adjusted by the paint temperature adjustment circulation system, and all the paint flowing through the paint supply circulation system is heated / cooled to an appropriate temperature. In addition, since the paint is circulated to repeatedly pass through the heat exchanger for heating / cooling, even a small heat exchanger can adjust the temperature to a temperature higher or lower than an appropriate temperature. Then, when the paint whose temperature has been adjusted by the paint temperature adjusting circulation system is caused to flow into the paint supplying circulation system at a required flow rate, the paint is adjusted to a temperature higher or lower than the optimum temperature even if the inflow is small, It is mixed with the paint flowing through the paint supply circulation system and adjusted to an appropriate temperature.

[0008]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to specific embodiments shown in the drawings. FIG. 1 is a flow sheet showing an example of the paint circulating and supplying device according to the present invention, and FIG. 2 is a flow sheet showing another embodiment.

According to this embodiment, the paint tank 1 is provided with a paint forward pipe 2
And the paint return pipe 3 are connected, and a plurality of coating machines 6,
6 are connected to the paint forward pipe 2 and the paint return pipe 3 via a paint supply hose 4 and a paint recirculation hose 5 to form a paint supply circulation system S. A pressure feed pump 7 for circulating the paint stored in the paint tank 1 is interposed in the paint forward pipe 2, and a coating machine 6 is attached to each paint supply hose 4.
A paint regulator 8 for quantitatively supplying paint is installed in the paint tank 1. When the pump 7 is started, the paint in the paint tank 1 is not affected by whether the paint is being discharged from the paint machine. It is circulated and supplied from the outward pipe 2 through the paint supply hose 4, the paint recirculation hose 5, and the paint return pipe 3 to return to the paint tank 1.

In the paint supply circulation system S, a part of the paint flowing in the circulation system S is taken in, the temperature is adjusted to a temperature higher or lower than an appropriate temperature, and then the paint supply circulation system S is returned to the paint temperature adjustment circulation system. System H is connected. A circulation pump H for adjusting temperature and a heat exchanger 10 are provided in the circulation system H for adjusting the temperature of the paint, and a part of the paint passing through the pump 9 and the heat exchanger 10 is an outlet Hb of the circulation system H. Is returned to the paint supply circulation system S, and the rest is circulated in the circulation system H. The outflow port Hb is connected to the paint outflow pipe 2 upstream of the paint regulator 8 interposed in the paint supply circulation system S, and the inflow port Ha is connected to the outflow port H.
It is connected to the paint supply circulation system S excluding the flow path from b to the coating machine 6, and in this example, is connected to the paint forward pipe 2 on the upstream side of the outlet Hb.

A circulation path F ₁ forming a paint temperature control circulation system H, a connection flow path F ₂ from the inflow port Ha to the circulation path F _1, and a flow path from the circulation path F ₁ to the outflow port Hb. Flow rate adjusting valves V ₁ , V ₂ and V ₃ are provided in F ₃ respectively. The flow rate adjusting valves V ₁ , V ₂ and V _{3 are used} to change the paint supply circulating system S to the paint temperature regulating circulating system H.
Flow rate of the paint flowing into the paint flow control system H is equal to that of the paint flow circulating from the paint temperature control circulation system H to the paint supply control system S, and is less than the paint flow rate circulating in the paint temperature control circulation system H. While being set to the flow rate, each flow rate is controlled by a control signal output from the controller C based on the paint temperature detected by the temperature sensor T provided in the paint forward pipe 2, for example.

The above is an example of the configuration of the present invention, and its operation will be described below by taking as an example the case where the temperature of the circulating paint is heated to an appropriate temperature. First, the pressure pump 7
Is activated, the paint in the paint tank 1 flows from the paint forward pipe 2 through the paint supply hose 4 and is supplied to the coating machine 6,
When the paint is not being discharged from the coating machine 6, all the paint passes through the coating machine 6, and when the paint is being discharged from the coating machine 6, the paint which is not discharged is the paint recirculation hose 5, the paint. It is circulated and supplied so as to flow through the return pipe 3 and return to the paint tank 1 again.

Then, a part of the low temperature paint flowing through the paint supply circulation system S is taken into the paint temperature adjustment circulation system H via the connection flow path F ₂ , and at the same time the paint temperature adjustment circulation system H is heated to a high temperature. The coating material heated to 1 is returned to the coating material supply circulation system S via the connection flow path F ₃ . At this time, a required amount (for example, 30 liters / minute) of the coating material circulates in the circulation path F ₁ in the coating material temperature adjusting circulation system H, passes through the heat exchanger 10 many times, and is heated to a temperature higher than an appropriate temperature. And the flow rate of the paint flowing from the paint supply circulation system S into the paint temperature adjustment circulation system H via the connection flow passage F ₂ and from the paint temperature adjustment circulation system H via the connection flow passage F _3. The flow rate of the paint returned to the paint supply circulation system S is controlled to be smaller than the flow rate of the paint circulating in the paint temperature adjustment circulation system H (for example, 5 liters per minute).

That is, when 5 liters of low temperature paint flows into the paint temperature adjusting circulation system H from the paint supplying circulation system S via the connection flow path F ₂ , 5 liters of high temperature paint is applied to the paint temperature adjusting circulation system H. Is returned to the paint supply circulation system S via the connection flow path F ₃ and 30 liters of paint is circulated in the heat circulation path F ₁ . Therefore, a large amount of low-temperature paint does not flow into the paint temperature adjusting circulation system H, and a large amount of high-temperature paint does not flow out from the paint temperature adjusting circulation system H. The temperature of the paint circulating in the tank is maintained substantially constant.

When, for example, 30 liters of paint per minute is sent to the paint supply circulation system S by the pressure pump 7,
At the same time as 5 liters of paint flow out from the paint supply circulation system S to the paint temperature adjustment circulation system H via the connection flow passage F ₂ , from the paint temperature adjustment circulation system H via the connection flow passage F _3. Since 5 liters of high-temperature paint flows into the paint supply circulation system S per minute, 5 liters of high-temperature paint is mixed with 25 liters of low-temperature paint. In this case, since the paint is heated to a temperature higher than the optimum temperature by the paint temperature adjusting circulation system H, the paint supplied to each coating machine 6 is heated to the optimum temperature even if the inflow rate is as low as 5 liters per minute. To be done.

Thus, in this example, the paint supply circulation system S
It is supplied to the coating machine 6 by not heating all the paint flowing through to a suitable temperature, but heating a small amount of the paint to a temperature higher than the optimum temperature, returning this to the paint supply circulation system S, and mixing it with the low temperature paint. The paint is heated to an appropriate temperature, and when heating a small amount of paint, the amount of heat accumulated in the paint circulating in the paint temperature control circulation system H can be used to heat the paint. Even if the exchanger 10 is used, it can be heated to a sufficiently high temperature.

FIG. 2 is a flow sheet showing another embodiment. It should be noted that, although the same parts as in FIG. 1 are denoted by the same reference numerals and detailed description thereof is omitted, in this example, the paint heated by the paint temperature adjusting circulation system H is supplied to each of the coating machines 6. It is done like this. That is, the paint temperature adjusting circulation system H includes a temperature adjusting circulation pump 9 and a heat exchanger 1.
0 is interposed and the paint heated / cooled by the heat exchanger 10 is circulated through the high temperature paint forward pipe 11, each high temperature paint hose 13 branched from the high temperature paint forward pipe 11, and the high temperature paint return pipe 12. In addition, each high-temperature paint hose 13 is connected to the upstream side of the paint regulator 8 interposed in each paint supply hose 4 via each flow rate adjusting valve V ₃ , V ₃ , V ₃ . Also, the inlet Ha of the circulation system H for adjusting the paint temperature
However, the paint return pipe 3 that returns the paint from the painting machine 6 to the paint tank 1
It is connected to the.

Therefore, in the present example, the paint flowing from the paint supply circulation system S into the paint temperature adjustment circulation system H is pressure-fed by the temperature adjustment circulation pump 9 and is sent to the heat exchanger 10.
After being heated at 1, the high temperature paint forward pipe 11, high temperature paint hose 1
3. After passing through the high-temperature paint return pipe 12, it is circulated again by circulating into the circulation pump 9 and heated to a high temperature in the same manner as the above-mentioned embodiment. By doing so, the coating material supplied to the coating machine 6 can be heated to an appropriate temperature.

As described above, also in this embodiment, by heating a small amount of paint to a high temperature and returning it to the paint supply circulation system S and mixing it with a low temperature paint, the paint supplied to the coating machine 6 is heated to an appropriate temperature. The heat amount accumulated in the paint circulating in the paint temperature adjusting circulation system H can be effectively used when heating a small amount of paint, so a small heat exchanger 10 is sufficient. .

In the embodiment, the case where the paint is heated to an appropriate temperature has been described, but the present invention is not limited to this, and the case where the refrigerant is supplied to the heat exchanger 10 to cool the paint when the temperature of the paint is higher than the optimum temperature. May be. Moreover, the number of the coating machines 6 is not limited to the case where a plurality of coating machines 6 are installed in the coating material circulation supply system S, and may be one.

Further, the inflow port Ha of the circulation system H for adjusting the temperature of the paint is provided with a paint forward pipe 2, a paint return pipe 3, a paint supply hose 4,
It is not limited to the paint recirculation hose 5 and may be connected to the paint tank 1. Furthermore, the present invention can be applied not only to the case of supplying a single color paint but also to the case of supplying a multicolor paint to each coating machine 6 through a color changing device (not shown). The coating supply circulation system S and the coating temperature control circulation system H may be provided for each color of coating.

[0022]

As described above, according to the present invention, a part of the paint flowing through the paint supply circulation system is made to flow into the paint temperature adjustment circulation system for heating or cooling, Not all the paint flowing through the paint supply circulation system is heated or cooled, and moreover, the paint is circulated in the paint temperature control circulation system to pass through the heat exchanger many times, so that the temperature higher than the appropriate temperature or Since it can be heated or cooled to a low temperature, the temperature can be adjusted efficiently even with a small heat exchanger. If this high-temperature paint or low-temperature paint is made to flow into the paint supply circulation system at the required flow rate, it will be supplied to the coating machine. It has a very excellent effect that the temperature of the entire paint can be adjusted to an appropriate temperature.

[Brief description of drawings]

FIG. 1 is a flow sheet showing an example of a paint circulating and supplying device according to the present invention.

FIG. 2 is a flow sheet showing another embodiment.

FIG. 3 is a flow sheet showing a conventional paint circulating and supplying device.

[Explanation of symbols]

 S ... Paint supply circulation system H ... Paint temperature adjustment circulation system Ha ... Inlet Hb ... Outlet 1 ... Paint tank 2 ... Paint forward pipe 3 ... Paint return pipe 4・ ・ ・ Paint supply hose 5 ・ ・ ・ Paint recirculation hose 6 ・ ・ ・ Painting machine 7 ・ ・ ・ Pressure pump 8 ・ ・ ・ Paint regulator 9 ・ ・ ・ Circulation pump for temperature adjustment 10 ・ ・ ・ Heat exchanger

Claims (1)

[Claims] 1. A paint in which a paint feeder (2) and a paint return pipe (3) in which paint is circulated are connected to a painter (6) through a paint supply hose (4) and a paint recirculation hose (5). In a paint circulating and supplying device including a supply circulating system (S), a part of the paint flowing through the paint supplying circulating system (S) is taken out, heated or cooled, and then again the paint supplying circulating system (S). A circulation system (H) for adjusting the paint temperature is formed.
The paint temperature adjusting circulation system (H) is provided with a temperature adjusting circulation pump (9) and a heat exchanger (10) for returning the paint to the paint supplying circulation system (S). Is connected to the paint supply hose (4) or the paint forward pipe (2) on the upstream side of the coating machine (6), and the inlet (Ha) for taking in the paint from the paint supply circulation system (S) is A paint circulating and supplying device characterized by being connected to a paint supplying circulation system (S) excluding a flow path from an outlet (Hb) to a coating machine (6).