JPH02149370A - Force feed system for coating material - Google Patents

Abstract

PURPOSE:To obviate the need for replacement of a high pressure tank by providing an air dryer for removing water from compressed air and a regulator for reducing the pressure of the compressed air. CONSTITUTION:Air from a compressed air source is passed through a filter 84 to remove dusts and foreign substances therefrom and reduced in pressure by a regulator 85. It is then cooled by an air dryer 87 to remove water therefrom, further reduced in pressure by a regulator 88, passed through a solvent tank 95 and, from an air line LN 6, it flows through a connector 126 into a primer tank 98. Thereafter, the inner pressure of a primer tank 98 rises and the force of a pressure is exerted upon the liquid surface of black primer BP filled in a primer container 127, thereby forcing the same out from a primer line LN 8 for delivery under pressure. This eliminates the possibility of the coating material being solidified.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a pressure feeding system for pumping coating agents such as primers, paints, or adhesives, particularly coating agents that harden or react with moisture in the air. Regarding.

[Conventional technology]

BACKGROUND ART Conventionally, when applying a coating agent, a system that uses pressure gas to forcefully transport the coating agent has often been used.

In conventional pumping systems, the pressure gas source is 150K.
A high-pressure tank filled with high-pressure nitrogen gas of approximately g/cd is used.

The pressure of nitrogen gas from the high-pressure tank is too high to pump the coating agent, so it is successively reduced by two or three stages of regulators, and the final amount is 0.1 to 0.5 kg/
It is applied to the pressure vessel as an extremely low pressure of c1g.

[Problem to be solved by the invention]

The conventional pressure-feeding system described above uses a high-pressure tank, so the difference between the pressure required to pump the coating material and the pressure required to pump the coating agent is extremely large (
, Since the accuracy of the set pressure was poor with a two-stage regulator, the pressure had to be reduced in multiple stages. Therefore, a lot of cost is required for the regulator, and depending on the number of stages of the regulator and the set pressure value, if the pressure of the nitrogen gas filled in the high-pressure tank decreases significantly due to use, the pressure applied to the pressure vessel will decrease. However, there is a problem in that the flow rate of the coating agent being pumped is reduced and uniform coating is not performed.

In addition, since high-pressure tanks are large in both volume and weight, it is not easy to replace them, and a transport path must be secured for replacement, which increases the floor space required for the pressure transfer system. there were.

In view of the above-mentioned problems, the present invention has been devised to provide a pressurized coating agent delivery system that adds pressurized gas with no pressure fluctuations to a pressure vessel to maintain a constant flow rate of coating agent, and eliminates the need to replace a high-pressure tank as in the past. is intended to provide.

[Means to solve the problem]

In order to solve the above-mentioned problems, the present invention is a pressure feeding system for pumping a coating agent using pressurized gas, and the set pressure of the second regulator that reduces the pressure of compressed air from a compressed air source is determined by the viscosity of the coating agent. For example, 0.1 to 0
．． It is selected to be around 5Kg/cd.

The pressure vessel contains a coating agent, and the coating agent is pumped by compressed air from the second regulator.

〔Example〕

Embodiments of the present invention will be described below with reference to the drawings.

FIGS. 1(a) and 1(b) are fluid circuit diagrams of a pumping system 3 according to the present invention. In this embodiment, a case will be described in which black primer BP is pumped as a coating agent.

The pressure feeding system 3 includes an adjustment section 81 for supplying clean air whose pressure has been appropriately adjusted, and a supply section 82 for supplying the black primer BP using the air pressure.

The adjustment unit 81 includes a port 83 for receiving air from a compressor (not shown), and an auto-drain filter 8.
4. A second regulator for roughly adjusting the pressure, an air dryer for removing moisture contained in the compressed air from the second regulator, and a second regulator for reducing the pressure of the compressed air from the air dryer; and a pressure vessel that pumps the coating agent using compressed air from the second regulator.

[For production]

Compressed air from a compressed air source, such as an air compressor or an air tank, is subjected to a first stage of pressure reduction by a first regulator.

The set pressure of the second regulator is selected to be lower than the pressure of the compressed air source and at which the air dryer functions efficiently, for example, 3 to 8 kg/c++.

The air dryer cools the compressed air from the first regulator and removes moisture contained in the compressed air.

Compressed air from which moisture has been removed by an air dryer is
A second stage of pressure reduction is performed by the second regulator.

regulator 85, pressure gauge 86, air dryer 87 for removing moisture and moisture, regulator 88°92 for precise pressure adjustment in normal air line LN1 and cleaning air line LN2, pressure gauge 89.93,
stop valves 90, 94, and both airlines LNI,
It is comprised of a switching valve 91 for switching air from 2 and the like.

The supply unit 82 includes a pumping device 80 having a solvent tank 95 containing the anti-hardening solvent SE, a stop valve 96, a pressure gauge 97, a primer tank 98, and the like.

The air dryer 87 lowers the temperature of input high-temperature air, discharges and removes condensed water, lowers the dew point to about 0 degrees Celsius on the liner, and prevents condensation in subsequent lines. It is of a known structure in itself, incorporating an exchanger, a pre-filter, a final filter, an automatic drainer, etc.

However, by using this air dryer 87,
There is no need to worry about the black primer BP reacting with moisture and curing, and there is no need for special piping for nitrogen gas, which is required in the conventional case of using high-pressure nitrogen gas. The pressure can be adjusted,
By adding air with no pressure fluctuation to the rear primer tank 98, the flow rate of the black primer BP can be kept constant, and there is no need to replace the high-pressure tank filled with nitrogen gas as in the conventional case. Also, black primer BP
Since the flow rate required for application is small, a small air dryer 87 can be used and the air dryer 87 can be stored compactly.

As shown in FIG. 1(b), the solvent tank 95 has a cylindrical tank body 111 sealed with a lid 112.
The solvent SE is pressurized by the air pressure from the air line LN5, and the solvent SR is sent out from the solvent line LN7. Also, the air that has entered the solvent tank 95 is connected to the air line L.
It flows out from N6 and flows into the primer tank 98.

When the solvent SR is insufficient, the solvent S is added to the hopper 113.
A pipe 122 connected to the brimer line LN8 via a connector 121 and a liquid level detection sensor 99 are attached to the R lid 117 in a sealed manner by screw type bushes 120 and 123, respectively. This primer tank 98 is attached to the mounting plate 3a of the coating agent supply device 3.
It is attached via a mounting fitting 128 to a bolt or the like (not shown).

Next, the operation of the pumping system 3 configured as described above will be explained.

The pressure in each part of the fluid circuit is set to approximately 7 kg/cIN by the regulator 85 and approximately 0.1 kg/cIN by the regulator 88.
~0.5Kg/cJ! Approximately 2 by O regulator 92
Kg/crM, respectively. The switching valve 91 switches the normal air line LNl to the air line LN5.
It is located in a position where it connects with.

The exchange valve 101 is located at a position to connect the primer line LN8 to the supply line LN9.

Air of about 10Kg/cffl from a compressed air source is
Dust, foreign matter, etc. are removed by the filter 84, and the stop valve 96 is opened to replenish the water. 114 is a safety valve.

FIG. 2 is a sectional front view of the pumping device 80 used in the pumping system 3 of FIG.

In FIG. 2, the primer tank 98 is composed of a tank body 116 and a lid 117.

The tank body 116 is composed of a bottom plate 115 and a tube 116a that are integrated by screws or welding, and an opening 116b at the top of the tank body 116 is formed by a lid 117 that is clamped by a clamp device IIB, 11B, etc. It is sealed by being removably attached.

On the bottom plate 115 is a pedestal 119 made of synthetic resin or the like.
is removably mounted on the pedestal 119, and a cartridge-type primer container 127 filled with black primer BP is placed on the pedestal 119 with its cap removed, with the inner circumferential surface 127a of the bottom facing the pedestal. It is positioned and placed so that it fits into the outer circumferential surface 119a of the convex portion 119.

It is cleaned by the regulator 85 and weighs about 7Kg/
The pressure is reduced to cIi. Thereafter, the air dryer 87 cools down and removes moisture as described above. Next, about 0, 1~
It is depressurized to 0,5 Kg/cdl, passes through the solvent tank 95, and is connected to the connector 12 from the air line LN6.
6 into the primer tank 98. As a result, the pressure inside the primer tank 98 increases, and the liquid level of the black primer BP filled in the primer container 127 is pressed. Then, the black primer BP is fed under pressure from the brimer line LN8 via the pipe 122.

The liquid level detection sensor 99 has a thermistor sealed at its tip (lowest end), and a constant current is supplied to the thermistor from the lead wire 125.
It is configured to detect a change in the heat dissipation state due to the presence or absence of P as a change in resistance value due to a change in temperature of the thermistor. This liquid amount detection sensor 99 detects that the black primer BP in the brimer container 127 is empty.

When the black primer BP in the primer container 127 is empty, the air from the air line LN6 is stopped to release the pressure in the primer tank 98, and then the clamp device 118 is operated to remove the lid 117 and the black primer BP is removed. Replace with a new, non-sedimented primer container 127 filled with primer and well shaken.

Therefore, it is extremely easy to replenish the primer tank 98 with black primer BP, and each time the primer container 127 is replaced, it can be shaken to use a container in which the black primer BP does not settle. By setting the capacity of the primer container 127 to an appropriate amount according to the daily usage amount in the pressure-feeding system 3, and by shaking it well before replacing, the black primer BP in the primer container 127 is heated until sedimentation occurs. There is no need to use it up and shake it again. It is also supplied to the primer container 127. In addition, the air supplied by the air line LN3 is input to the above-mentioned switching valve 103, and is also input to the regulator 1.
04 and the electromagnetic switching valve 105, the load is input to the parallel opening/closing drive chuck 14, and the switching valve 105 is controlled on/off to cause the parallel opening/closing drive chuck 14 to perform opening/closing operations.

To clean the switching valves 101, 102, coating material supply jig 12, etc., switch the switching valve 91 to connect the cleaning air line LN2 to the air line LN5, and switch the switching valve 101 to supply the solvent line LN7. Line LN
Connect to 9.

As a result, the solvent SE in the solvent tank 95 is pressurized at a high pressure and flows into equipment such as changeover valves 101 and 102, and black primer BP, etc. adhering to the equipment is washed away, causing clogging and malfunction. is prevented. Also,
The primer line LN8 can also be cleaned by replacing the primer container 127 in the primer tank 98 with a container containing the solvent SE.

Even if the black primer BP remains unused for a long period of time, the primer container 127 can be taken out from the primer tank 98 and shaken easily, so that the concentration of the black primer BP pumped from the primer line LN8 can be reduced. It becomes uniform, which is extremely convenient for coating in the subsequent process, and the thick liquid of the black primer B1) does not remain at the bottom of the primer container 127 (there is no uneconomical effect. The inside of the primer tank 98 is hardly contaminated. So it is easy to clean.

Since the base 119 is made of synthetic resin, it is easy to clean.

In addition, in FIG. 1(b), primer line LN8
Black primer BP and solvent line L are pumped from
The solvent SE pumped from N7 is switched by the switching valve 101 and sent to the pilot type switching valve 102, and by switching the electromagnetic type switching valve 103, the solvent SE is transferred to the black primer via the supply line LN9. Boat 6 of coating agent supply jig 12 that requires BP
7 In the embodiments described above, the fluid circuit of the pumping system 3 can be modified in various ways. For example, if the filter 84 is replaced with a two-stage configuration of a coarse mesh filter and a fine mesh filter, even cleaner air can be obtained. Further, a switching valve for relief may be provided in the middle of the airline LN5. Regulator 85.
The pressure set by 88 can be changed in various ways. The regulator may have three or more stages. Pumping device 80 may be of other constructions. It is applicable to various coating agents other than Black Brimer BP.

In the above-described embodiment, the bushings 120 and 123 are of the screw type, but they may be of the welded type. Instead of the connector 126, a socket, flange, etc. may be used. Although the inner circumferential surface 127a of the primer container H127 and the outer circumferential surface 119a of the pedestal 119 are configured to fit together, the present invention is not limited to this.

Clamping device 118 can be of various types. The structure, shape, arrangement, material, etc. of the other constituent members may be various other than those described above.

(Effects of the Invention) According to the present invention, since the pressure difference is small, precise pressure adjustment is possible, pressure gas with no pressure fluctuation can be added to the pressure vessel, and the flow rate of the coating agent is kept constant. Since there is no need for a high-pressure tank like in the past, there is no need to replace the high-pressure tank.

In addition, the air dryer can lower the dew point, which eliminates the risk of curing the coating material, eliminates the need for special piping for conventional nitrogen gas, and replaces the conventional high-pressure tank. Since it can be handled with a small air dryer, it can be stored compactly.

[Brief explanation of the drawing]

The drawings show embodiments of the invention, FIGS. 1(a) and (b)
2 is a fluid circuit diagram of the pumping system, and FIG. 2 is a sectional front view of the pumping device used in the pumping system of FIG. 3... Pressure feeding system, 85... Regulator (second
regulator), 87... air dryer, 88...
-Regulator (second regulator), 98...primer tank (pressure vessel), BP...black primer (coating agent).

Claims (1)

[Claims] (1) A pressure-feeding system for force-feeding a coating agent using pressurized gas, the system including a first regulator that reduces the pressure of compressed air from a compressed air source, and removes moisture contained in the compressed air from the first regulator. A pressure-feeding system for a coating material, comprising: an air dryer for reducing the pressure of the compressed air from the air dryer, a second regulator for reducing the pressure of the compressed air from the air dryer, and a pressure vessel for pressure-feeding the coating material by the compressed air from the second regulator. .