JPH0316186B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for applying a reaction-curing paint for carrying out a painting operation using a two-component reaction-curing paint or a three-component reaction-curing paint.

In general, reaction-curing paints such as polyurethane resin paints, unsaturated polyester resin paints, and epoxy resin paints have a low solvent content and can be reaction-cured at room temperature without requiring thermal energy to cure and dry the coating. It is attracting attention.

However, due to pot life issues, it is impossible to manufacture and distribute this reaction-curing paint in a blended or mixed state, and it is made up of two components: a base agent and a curing agent, or a three-component component: a base agent, a curing agent, and an additive. The problem is that these components must be handled as separate containers and supply systems, and must be mixed and then sprayed immediately before coating. In addition, depending on the type of base agent, the type of pigment contained in the base agent, etc., the mixing ratio of the base agent and curing agent, or the mixing ratio of the base agent, curing agent, and additive must be controlled with high precision. The problem is that it does not.

Therefore, in the conventional method, a mixture is created by mixing the base agent and hardener supplied from the base agent supply system and the hardener supply system, respectively, and this mixture is transferred from the coating machine to the object to be coated. When spraying toward the target, a two-liquid constant ratio pump consisting of a pair of pumps or a pair of measuring cylinder devices is inserted between the base agent supply system and the curing agent supply system, and the discharge volume ratio of these pumps or the distance between each measuring cylinder device is It is known that the mixing ratio is managed by changing the stroke ratio.

However, the conventional method described above has the disadvantage that the rotation ratio of the two-liquid constant ratio pump or the stroke ratio of the metering cylinder device must be mechanically changed every time the mixing ratio is changed, and the operation is extremely troublesome. It was hot. In addition, since the conventional method described above is controlled in a sequential manner, even if the mixing ratio is accurately controlled, fluctuations in the supply amount due to ambient conditions such as temperature and viscosity cannot be constantly monitored. . Furthermore, it is not possible to configure a system that continuously sprays many types of paint while changing the type of base agent or paint color, and the mixing ratio of additives must be managed separately. The disadvantage was that it had to be done.

The present invention has been made in view of the above-mentioned drawbacks.
A reaction curing type that enables mixing immediately before painting, and also measures the supply amount of the main agent and curing agent flowing from the circulation pipe, and maintains a highly accurate mixing ratio based on the measurement results. The purpose of this invention is to provide a method for applying paint.

In order to achieve the above object, the feature of the configuration adopted by the present invention is that the supply amounts respectively supplied from the main agent supply system and the curing agent supply system connected to the circulation pipe are connected to the main agent supply system and the curing agent supply system. The supply ratio of the main agent and curing agent measured by each flow meter is measured with a preset mixing ratio,
Based on the comparison result, regulators provided in the main agent supply system and the curing agent supply system are adjusted to control the supply amount of the main agent and curing agent so that the mixture ratio is set in advance. It is in.

The present invention will be described below based on embodiments shown in the drawings.

In the figure, reference numeral 1 indicates a color change valve device, and the color change valve device 1 includes a manifold 2 having a passage 2A inside, an air valve 3 whose outflow side is connected to the passage 2A, a thinner valve 4, and a plurality of main agent valves 5. , 6, 7, a curing agent valve 8 and an additive valve 9. Each of the valves 3 to 9 is, for example, an air-driven spring return type 2-port 2-position switching valve. -9 are normally in the closed position unless control air is supplied. The air valves 3 and thinner valves 4 are arranged on the most upstream side of the manifold 2, the air valves 3 are connected to an air source 11 via an air pipe 10, and the thinner valve 4 is connected to a thinner valve via a thinner pipe 12. It is connected to a circulation pipe 13 connected to the source. Note that the thinner source may be a thinner tank instead of the circulation pipe 13.
On the other hand, the main agent valves 5, 6, 7 are connected to the main agent pipes 14, 1.
The curing agent valve 8 is connected to the circulation pipes 17, 18, and 19 of A, B, and C colors through curing pipes 5 and 16. 21 and the additive valve 9 are respectively connected to an additive circulation pipe 23 via an additive pipe 22. In addition, each of the circulation pipes 17
- 19, 21, and 23 are each provided with a pump in the middle, and are circulated between the main agent tank, curing agent tank, and additive tank of colors A, B, and C.

Reference numeral 24 indicates an outflow pipe, one end of which is connected to the outlet of the passage 2A of the manifold 2, and the other end connected to a line mixer 25 such as a static mixer. Further, a paint pipe 26 is connected to the outlet of the line mixer 25, and a paint machine 27 made of, for example, an air gun or an airless gun is provided at the tip of the paint pipe 26, and the paint machine 27 can be moved to a high altitude as needed. A voltage is applied to constitute an electrostatic coating machine.

28, 29, 30, 31, 32 are pipes 14, 1
5, 26, 20, and 22, and the flow meters 28 to 32 are equipped with flow rate transmitters 33, 34, which transmit a flow rate signal proportional to the measured flow rate.
35, 36, 37 are installed, and each flow rate transmitter 3
3 to 37 are signal lines 38, 39, 40, 41, 42
It is connected to a control device, which will be described later.

Further, 43 is a control device consisting of, for example, a hard circuit, a microcomputer, etc., and 44 is a mixing ratio setting device that automatically sets the mixing ratio of the base resin, curing agent, and additive to a desired ratio according to the type of each base resin. , the control device 43 uses a predetermined mixture ratio that is preset and inputted by a mixing ratio setting device 44 and the flowmeters 28 to 3 that are inputted via signal lines 38 to 42.
It has a function of comparing the flow rate signals from the flow rate transmitters 33 to 37 of No. 2 and outputting a control signal based on the comparison result so that the valve opening of the regulator, which will be described later, becomes a preset mixing ratio.

Furthermore, 45 indicates an electro-pneumatic converter, and the electro-pneumatic converter 45 receives control signals from the control device 43 inputted via signal lines 46, 47, 48, 49, and 50, and corresponds to the control signals. It has a function to output as an air control signal. 51, 52, 53, 5
Reference numerals 4 and 55 indicate regulators provided in the middle of each of the pipes 14 to 16, 20, and 22 and upstream of the flowmeters 28 to 32. An air-driven liquid regulator is used to adjust the valve opening. Each of the regulators 51 to 55 is connected to the electro-pneumatic converter 45 via air pipes 56, 57, 58, 59, and 60, and output is output from the electro-pneumatic converter 45 via each of the air pipes 56 to 60. It has the function of adjusting the valve opening degree in response to each air control signal.

The coating apparatus used in the present invention is constructed as described above. Next, a coating method using this coating apparatus will be described.

It is now assumed that all the elements constituting the above-mentioned apparatus have been thoroughly cleaned. In this state, it is assumed that a painting operation is performed using the main agent of color A from the circulation pipe 17.

Assuming that the mixing ratio of the main material, curing agent, and additive for this color A main material is 10:2:1, the ratio is set by the mixing ratio setting device 44 when starting the painting operation. The control device 4 automatically controls the value
3 and store it in that storage area. Note that this setting operation may be a manual setting.

Next, control air is supplied to the main agent valve 5, curing agent valve 8, and additive valve 9 to switch the valves, and at the same time, the control device 43 sends an electro-pneumatic converter via signal lines 46, 49, and 50. A control signal corresponding to the above-mentioned mixing ratio is output to the converter 45, and an air control signal corresponding to this control signal is output from the electro-pneumatic converter 45,
This air control signal is input to the regulators 51, 54, 55 via the air pipes 56, 59, 60, respectively, and only the regulators 51, 54, 55 are opened to open the valve corresponding to the above-mentioned mixing ratio of 10:2:1. Set once. At this time, other regulators 52, 53
is in a closed state.

As a result, the main agent of color A from the circulation pipe 17 is transferred to the main agent pipe 14 and the regulator 5.
1. The curing agent is supplied to the line mixer 25 via the flow meter 28, the main agent valve 5, the manifold 2, and the outflow pipe 24, and the curing agent from the circulation pipe 21 is supplied to the curing agent pipe 20, the regulator 54, and the flow meter 31. , the curing agent valve 8, the manifold 2, and the outflow pipe 24 to the line mixer 25, and the additive from the circulation pipe 23 is supplied to the additive pipe 22, the regulator 55, the flow meter 32, and the additive It is supplied to the line mixer 25 via the valve 9, manifold 2, and outflow pipe 24. The mixture obtained by mixing the base agent, curing agent, and additives by the line mixer 25 is supplied to the coating machine 27 via the paint pipe 26, and from the coating machine 27 to the object to be coated. It is sprayed towards.
It goes without saying that some mixing is also performed in the middle of the outflow pipe 24 from the manifold 2 to the line mixer 25.

Meanwhile, the flow rate of the main agent, curing agent, and additives flowing in the pipes 14, 20, and 22 during this time is measured by the flowmeter 2.
8, 31, and 32, respectively, and this measured flow rate is inputted to the control device 43 via signal lines 38, 41, and 42 every moment. As a result, the control device 43 constantly compares a predetermined mixing ratio that has been set and stored in advance with the flow rate signal input from each flow rate transmitter 33, 36, 37, and based on the comparison result, the signal line A control signal for maintaining a predetermined mixing ratio is output to the electro-pneumatic converter 45 via 46, 49, and 50, and an air control signal corresponding to this control signal is output from the electro-pneumatic converter 45, The regulators 51, 54, and 55 are adjusted to valve opening degrees that provide a predetermined mixing ratio.

Furthermore, when the painting work of color A on the object to be painted is completed, the output of the control signal from the control device 43 to the electro-pneumatic converter 45 is stopped, and the output of the control signal from the control device 43 to the electro-pneumatic converter 45 is stopped.
4, 55 are closed, and the main agent valve 5, curing agent valve 8,
The supply of control air to the additive valves 9 is stopped to return them to their original switching positions, and the input of the setting value for the main ingredient of color A from the mixing ratio setting device 44 is reset.

However, since reaction-curing paints harden after their pot life, they must be cleaned as soon as possible. For this reason, after the painting work is finished, control air is automatically supplied to the air valve 3 to open it, and air from the air source 11 is supplied to the manifold 2 via the air piping 10, and the air flows out through the passage 2A. pipe 24,
Line mixer 25, paint pipe 26, paint machine 27
Purge the base agent and mixture remaining inside. When this is completed, control air is supplied to the thinner valve 4 to open it, and thinner from the circulation pipe 13 is supplied to the manifold 2 via the thinner pipe 12, and the passage 2A, the outflow pipe 24, The inside of the line mixer 25, paint pipe 26, and coating machine 27 is cleaned. Furthermore, if even a small amount of the main agent of color A remains in these systems, there is a risk of color mixing during the next painting operation, so after cleaning with thinner is completed, the air valve 3 is opened again, and the main agent of color A is removed. Purge the liquid and thinner and dry. The cleaning operation is completed in this manner, but the cleaning operation may be performed by repeating the above-mentioned steps several times as necessary.

As described above, the painting work and cleaning work using the main material of color A have been completed, but when performing the painting work using the main material of color B or C, it is sufficient to perform the same as described above. It is.

In the above example, a case was described in which a three-component reaction-curing paint consisting of a base agent, a curing agent, and an additive was used. It is suitable for low viscosity polyurethane resin paints, unsaturated polyester resin paints, etc., and for mixing surface tension lowering agents and curing retarders. On the other hand, in the case of a two-component reaction-curing paint made of a high-viscosity, high-solid paint for thick application, a solvent-free polyurethane resin paint, an epoxy resin paint, etc., additives may be unnecessary. In addition, although it has been described that the main agent valves 5 to 7, the hardener valve 8, and the additive valve 9 are provided in one manifold 2, the hardener valve 8 and the additive valve 9 are installed in separate manifolds together with separate thinner valves. They may be provided and merged on the upstream side of the line mixer 25. Further, although the line mixer 25 is used as the mixing means, an internal mixing type atomizer having a mixing mechanism inside the atomizer 27 may be used. Furthermore, although it has been described that the circulation pipes 17 to 19 circulate the base materials of colors A, B, and C, different types of base materials such as polyurethane resin paint, epoxy resin paint, unsaturated polyester resin paint, etc. It may also be something that circulates.

The method for applying the reaction-curing paint according to the present invention is as described above in detail, and the supply amount of the main agent and curing agent supplied from each supply system is measured by a flowmeter, and the supply ratio is calculated. Since the regulator installed in each system is adjusted to the preset mixing ratio by comparing it with the preset mixing ratio, fluctuations in the fluid flowing through the circulation pipe and external Even if there are changes in the environmental conditions, a highly accurate mixing ratio can be maintained at all times, and automatic color changes or main ingredient changes can be easily performed.

[Brief explanation of drawings]

The figure is a system diagram of a coating device used in the present invention. 1... Color change valve device, 2... Manifold, 3...
... Air valve, 4 ... Thinner valve, 5, 6, 7 ... Main agent valve, 8 ... Hardener valve, 9 ... Additive valve, 14, 1
5, 16...Main valve piping, 17, 18, 19, 2
1, 23...Circulation pipe, 20...
...Curing agent piping, 22...Additive piping, 24...Outflow piping, 25...Line mixer, 26...Paint pipe, 27...Painting machine, 28, 29, 30, 3
1, 32...flow meter, 33, 34, 35, 36,
37...Flow rate transmitter, 43...Control device, 44...
...Mixing ratio setter, 45...Electro-pneumatic converter, 51,
52, 53, 54, 55...Air-driven liquid regulator.

Claims (1)

[Claims] 1 A mixture is made by mixing the main agent and curing agent supplied from the main agent supply system and the curing agent supply system connected to the circulation pipe, respectively, and this mixture is directed from the coating machine to the object to be coated. In a method for applying a reaction-curing paint by spraying the paint, the amounts supplied from the main agent supply system and the curing agent supply system are measured by flowmeters installed in the main agent supply system and the curing agent supply system, respectively. The main agent and curing agent supply ratio measured by each flow meter is compared with a preset mixing ratio, and based on the comparison result, the main agent supply system and the curing agent supply system are A method for applying a reaction-curing paint, characterized in that the amount of supply of the base agent and curing agent is controlled to a preset mixing ratio by adjusting a regulator.