JPH0779979B2 - Paint exchanger - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a paint exchanger, and more particularly to a device suitable for selectively supplying different color paints to a paint applicator device.

There are many known paint exchangers that deliver paint of a selected color or component to a spray device, stop paint of a non-selected color or component, and clean the system during a selection operation, but The various types of paint exchangers used today inherently have some drawbacks.

Such defects are often due to paint parameters or properties, such as the viscosity and solids content of the paint used. For example, in many coating systems, the viscosity of the coating is high at low temperatures and spray coating is difficult, so it is necessary to heat the coating to lower the viscosity so that it can be easily spray coated.

With such heating, heat is applied to the paint at specific locations in the system. However, when the paint flow is stopped for a considerable period of time, the paint at the heating portion may be overheated, that is, overheated and scorched or damaged. On the contrary, the paint at a position away from the heater is cooled. As a result, the viscosity of the paint is affected, and the paint is atomized and the finished state varies.

Furthermore, for paints containing solids, such as metallic paints, the solids must be maintained in a uniform floating state in the paint supply and piping system during the coating operation.

However, as described above, when the paint flow is stopped for a considerable time, the solid matter in the paint settles down and the desired floating state is lost, and the sprayed paint film does not become uniform, and the electrostatic charge is also static. There are also grounding problems.

For example, known paint exchangers used in high pressure systems having operating ranges of 1000 psi (pounds per square inch) or more than 70.3 kg / cm ² are commonly referred to as dead end paint exchangers, or non-circulating color exchangers. The paint is normally transferred to the coater gun through a system that includes a paint changer manifold, but when the gun or coater is stopped or when the paint is not selected, the paint flow changes. Stops between the container manifold and the gun, and the paint circulates only between the paint supply and the manifold. The paint stopped between the gun and the manifold will cool down. Even if there is no temperature gradient, the solids settle out and become non-floating. Metallic paints and the like having such a high viscosity have two problems in the known system: cooling and sedimentation. Operating range, for example 80~200psi (5.6~14.1kg / cm ²⁾
Known recirculating paint exchangers for low pressure systems also used a bellows device to separate and seal the paint from the components of the paint valve actuator, however, such bellows could, for example, be 1000 psi (70.3 kg). If it is used in a high pressure system of / cm ² ) or more, it will be damaged.

Therefore, it is an object of the present invention to provide an improved paint exchanger.

Another object of the present invention is to provide an improved paint exchanger capable of preventing paint overheating and temperature gradients or non-floating due to settling of solids, both for selected and unselected paints. That is.

It is another object of the present invention to provide an improved paint changer that can easily increase or decrease the number of replaceable paints.

Another object of the present invention is to provide a fully recirculating paint exchanger for high pressure paint application systems.

To this end, the improved paint exchanger according to the preferred embodiment of the present invention comprises a plurality of mutually identical exchanger modules, these modules being provided for each paint selected. All paint of choice is completely recirculated, and during spraying of the high pressure painting system, the excess of select paint is continuously recirculated from its supply to the return.

The paint changer comprises a universal applicator feed manifold and a universal applicator return manifold, each of which is formed by interconnecting a plurality of module feed blocks and holes in the return block. It is formed. Each module also comprises a recirculation block forming a recirculation passage.

A normally closed supply valve provided in each module delivers unselected paint to a normally closed recirculation valve which is pneumatically opened in the recirculation block. This paint returns to its own supply through a recirculation passage. When this paint is selected, the supply valve is pneumatically opened and the recirculation valve is closed. Accordingly, the paint is delivered to the module's supply manifold block and then to the universal type supply manifold, spray gun and universal type return manifold. The paint from this return manifold flows to the return manifold block of the above module, and then to the normally closed return valve that is open at this time. This return valve is attached to the recirculation block and returns the paint to the supply via a common recirculation passage.

Each module preferably has one supply manifold block, one return manifold block, one recirculation block, and a supply valve connected to each of them.
A recirculation valve and a return valve, each of these supply, recirculation and return valves being controlled by a pneumatically actuated piston to supply the selected paint to the universal manifold and from its supply. When the paint is unselected, the paint is recycled, and when the paint is selected, the unused part of the paint is recycled.

This paint exchanger is particularly effective for high pressure airless sprays because no bellows are used for each valve.

There is one module for each paint. Also,
Each module includes a plurality of holes and a sealable port so that it can be easily articulated and secured to an adjacent module by screws. To increase the number of paints the basic paint exchanger according to the invention can handle, it is only necessary to add modules to this basic paint exchanger. For example,
The number of paints handled by the basic paint exchanger can easily be increased by simply connecting a number of additional modules equal to the number of paints desired to be added.

It is easy to assemble multiple modules, each module having a universal type return manifold and a return manifold, with the addition of piping and connections, except for the line connecting the additional paint supply and valve control solenoids. do not have to.

Furthermore, the above-mentioned complete recirculation is ensured during the paint operation,
The paint will not stagnate over long or significant areas. Also, when the paint of the selected module is being sprayed, areas of non-flo, such as between the supply valve and the recirculation valve of the selected module.
If w) is also homogenized by superheating and mixing, it is eventually recirculated through the feed and system before the subsequent application.

Since the manifold blocks are interconnected, the pressure drop in this system can be reduced by adding piping (color) between the paint valve ports or between the manifold parts of each module. In comparison, it does not grow much.

Furthermore, according to the invention, a solvent module and an air module are provided separately for cleaning the paint exchanger during paint (color) change. These solvent and air modules are located upstream of the universal return manifold, and a discharge valve is located downstream of the universal return manifold, which allows the entire system to operate during paint, e.g. color change. To be washed. A recirculation valve or recirculation block is required for the above modules, since the spent solvent is simply sent to the discharge valve via a line, and the air is also sent to the discharge valve via an exhaust hole or a line. Not.

Thus, the paint exchanger of the present invention is particularly effective when used with a high pressure airless system. If this paint exchanger is used in a high pressure system, the high pressure flow may hold the paint exchanger valves open, so these valves should have springs to assist in closing them. You may attach it.

As described above, the present invention provides a recirculation type paint exchanger in which any non-selected paint is always recirculated, and the surplus of the selected paint is returned to the supply section.

Additional modules are selected by forming part of each of the universal feed, manifold and return manifolds and easily adding to the base paint exchanger with the benefits of full recirculation described above in high pressure spray systems. You can increase the number of paints you can.

The above-mentioned and other objects and advantages will become more apparent by the detailed description of the preferred embodiments of the present invention given below with reference to the drawings.

A description will be given below with reference to the drawings. FIG. 1 shows a paint exchanger 10 according to a preferred embodiment of the present invention. This paint exchanger
The 10 is specifically configured for use in a coating system that applies two or more special colors to an object. This multicolor coating system is used in various fields.

Frequently it is desired to apply different types of paint, for example one or more conventional paints and solids-containing paints such as other metalic paints, in one paint system.

The paint exchanger 10 described herein is useful in various types of painting systems such as: That is, it is effective for various coating systems for coating two colors or two types of coatings using a special coating device such as an electrostatic coating spray gun or other type coating device.

Also, the paint exchanger approximately 1000psi (70.3kg / cm ²⁾ or more, such as those used in the high-pressure system of the order of 2000~3000psi (140~211kg / cm ^2).

As shown in the drawing, the paint exchanger 10 includes a basic two-color color exchanger or basic paint exchanger 11, and auxiliary color module means or color module 12 added to the basic paint exchanger 11. As a whole, the three-color color exchanger or paint exchanger 10 shown in FIG. 1 is constructed. This color module 12
The color paint module 12 is shown in a disassembled state from the basic paint exchanger 11 for ease of illustration, but in actual use, this color module 12 is connected to the basic paint exchanger 11 to form an integral paint exchanger 10. To do.

Further, the paint exchanger is usually used when two or more colors of paints or fluids or two or more kinds of paints or fluids are used in one application system. Furthermore, the basic paint exchanger 11 has two colors,
Alternatively, it is equipped with a selection means for selecting one paint from two kinds of paint, and when an auxiliary module such as the color module 12 is added, a multicolor or multicolor paint exchanger is constituted, whereby three colors are used. Alternatively, a desired one can be selected from three or more kinds of paints and fluids. The base paint exchanger 11 can be a one-piece construction or can be assembled from a plurality of modules, such as the color module 12, and a suitable valve component for venting and venting solvent and air.

Details of the paint exchanger of FIG. 1 will be described below. Paint exchanger
Reference numeral 10 has a universal type paint supply manifold 13 and a universal type paint return manifold 14.
As shown in FIG. 1, the paint supply manifold 13 and the paint return manifold 14 are formed in a machined aluminum block, for example, 15 and 16. Both blocks 15 and 16 are integral as shown in FIG. 1 and extend over the entire two-color or two-color basic paint exchanger 11. Blocks 15 and 16 will also be described below as color module 12, although separate assemblies may be made so that there is one block for each color or type.

Paint supply manifold 13 and paint return manifold
14 has ports 17 and 18, respectively, which are provided at end blocks 19 and 20, respectively, and which are connected, for example, to a suitable supply and return conduit leading to a suitable paint spray gun. . The end blocks 19 and 20 are provided at the end of the paint exchanger 10 for the above functions regardless of the number of modules used in the paint exchanger 10.

The color module 12 comprises a paint supply valve 25, a recirculation valve 26 and a paint return valve 27 not shown in FIG. 1 but clearly shown in FIGS. 2 and 3. The color module 12 also comprises a supply manifold block 28, a return manifold block 29 and a recirculation block 30. The paint supply valve 25 and the recirculation valve 26 are connected to each other by a connecting block 31 arranged between them. This connecting block 31 has a through hole 32 as shown in FIG. 2, and this through hole 32 is a normally open output port 33 provided in the paint supply valve.
Is connected to a normally open input port 34 provided in the recirculation valve 26. Similarly, the connection block 36 is mounted so as to extend between the return manifold block 29 and the paint return valve 27. This connection block has a through hole 37 that connects the output port 38 of the return manifold block 29 to the input port 39 of the paint return valve 27.

Both the recirculation valve 26 and the paint return valve 27 are recirculation blocks.
A common recirculation passage 41 is formed in the recirculation block 30.

As can be seen from FIGS. 1 and 2, the supply manifold block 28 is a universal type paint supply manifold.
Part 13a of 13 is built in. Similarly, on the return manifold block 29, a part 14a of the universal type paint return manifold 14 is formed. Part 13a of paint supply manifold 13 and paint return manifold 1
A portion 14a of 4 is provided in the position shown in FIG. 1 and is connected to the supply and return ports 17 and 18 of the end blocks 19 and 20. Of course, when using modules other than those described above, each module has a paint supply manifold 13 and a paint return manifold 14 similar to the color module 12.
Block for supply manifold that contains a part of each of
28 and return manifold block 29. Further, for example, a sealing means composed of a groove and an O-ring may be provided on the contact surface of these manifold blocks to prevent leakage from the paint supply manifold 13 and the paint return manifold 14.

Referring again to FIG. 1, two color or two types of basic paint exchanger 11
Also a color module for applying each color or type of paint
It includes the same structure as 12. That is, for example, a device for selecting a large number of color numbers 1 is a supply valve 25a corresponding to the supply, recirculation, and return valves 25 to 27 of the color module 12, respectively.
And a recirculation valve 26a and a return valve 27a (not shown). Similarly, a device for selecting paint color number 2 is, for example, a color module.
12 supply, recirculation, supply valve 25 corresponding to return valve 25-27
b, a recirculation valve 26b and a return valve 27b. Of course, as mentioned above, it is also possible for the device for color number 1 and the device for color number 2 to each be a separate module of the same configuration as the color module 12, but this two color or two It is convenient in terms of cost to configure the basic paint exchanger 11 of a kind as an integral unit as shown in FIG. 1 for the following reasons. That is, the basic paint exchanger 11 is used for work that requires only two colors or two kinds, and when trying to use a paint of another color or type, one or more color modules 12 of the same shape are provided in the basic paint exchanger 11. This is because it can be added.

The basic paint exchanger 11 further includes cleaning means for cleaning the entire system while changing the color or type of paint. For this purpose, the solvent supply valve 45 (Figs. 1 and 5) is blocked.
15 and is connected to a universal type paint supply manifold 13 on the upstream side of the coating devices for color numbers 1 and 2. Solvent is supplied to the inlet conduit 46 and the solvent supply valve
When the valve 45 is opened, it is introduced into the universal type paint supply manifold 13, sent from the paint supply manifold 13 to the gun, returned through the paint return manifold 14, and then sent to the discharge valve (Fig. 5). To be The apparatus for introducing this cleaning solvent into the system is somewhat similar to the color module 12 except that it does not include any recirculation valve, such as the recirculation valve 26 shown in FIG. . In this system, since it is not necessary to recirculate the solvent when not in use, the solvent supply valve 45 does not have the outlet port 33 unlike other valves, and for example, this portion is not blocked. Has been. Also used with the solvent device,
The outlet ports of recirculation blocks, such as recirculation block 30, are also blocked except where such ports lead to solvent and excess paint discharge.

Accordingly, when the solvent supply valve 45 is opened, the solvent can flow into the universal type paint supply manifold 13. The solvent flows from this paint supply manifold 13 through a conduit to the spray device, back to the universal paint return manifold 14 and then through a discharge valve 48. The discharge valve 48 is a valve similar to the paint return valve 27 shown in FIG. FIG. 5 shows an outline of this solvent apparatus. When the discharge valve 48 is opened, the solvent and waste paint are flowed to a waste paint tank (not shown).

Thus, the solvent flows into the system from the upstream side of all colors upstream of the paint supply manifold 13 and through the entire system to all paint return manifolds 14 and discharges downstream of the paint return valve 27. Flush to thoroughly clean system.

After flowing the solvent to each paint supply manifold 13 and paint return manifold 14 and the rest of the system,
It is desirable to drive out any solvent remaining in the system by sending pressurized air into those manifolds or other conduits or paint applicators. To this end, an air supply valve 50 is attached to the block 15 as well as being connected to the pressurized air supply source. This air supply valve is a universal paint supply manifold upstream of the solvent supply valve 45.
It is also connected to 13. When the air supply valve 50 is opened, the pressurized air causes the universal paint supply manifold 13, the intermediate conduit, the coating device, the universal paint return manifold 14, and the discharge valve, that is, the return valve 48.
(Fig. 5) and flows into the discharge part to expel the solvent from the system. For this reason, the discharge valve 48 is also opened during ejection by air.

The details of the particular color module 12 will now be described. The details of this color module 12 are similar to those of the module or device in the basic paint exchanger 11 for applying different or different colors of paint. Each module or coating device can be operated independently. The valves of the color module 12 are preferably controlled by pneumatically actuated pistons which control each module or the various valves 25-27 of the exchanger device in a predetermined manner. Each module is selectively operated by the paint applicator to select a particular color or type to be applied while at the same time recirculating paint of the unselected color or type.

2-5, the valve used in paint exchanger 10 is the type of valve used by the Applicant in the non-circulating dead end color exchanger, referred to as the A7A valve.

Each of valves 25, 26, 27 are similar to each other. First, the paint supply valve 25 will be described. This paint supply valve 25 is a paint supply conduit
The paint supply conduit 55 connects the paint supply to the valve port 56. The paint supply valve 25 includes a valve seat 57 and a reciprocating valve member, which reciprocating valve member is shown as a spherical valve member 58.
It is preferable that The spherical valve member 58 is a connecting rod.
It is attached to 59 and the upper end of this rod 59 is connected to a pneumatically actuated piston 60. The rod 59 is provided with a seal section above the paint inlet chamber 61, which seals the paint in the valve body and prevents the paint from leaking upward. The drain hole 64 prevents the paint leaking upward from entering the air system for the pneumatically actuated piston 60. Each module includes a plurality of air inlet ports, such as air inlet port 62 (see FIG. 1), which allows pressurized air to be supplied to expansion chamber 63. Each air inlet port 62 is equipped with a suitable air fitting and is thereby selectively connected to a source of pressurized air, or a discharge, which is selectively controlled. When it is desired to close the paint supply valve 25, the air pressure in the expansion chamber 63 is discharged from the air inlet port 62. As a result, the valve spring 65 urges the rod 59 and the spherical valve member 58 against the valve seat 57, and blocks the passage through the valve seat 57. Further, the paint supply valve 25 is normally controlled to be a normally closed valve which occupies the position shown in FIG.

In the state shown in FIG. 3, the paint flowing into the paint inlet chamber 61 through the paint supply conduit 55 is sent to the inlet port 34 of the recirculation valve 26 through the hole 32. The recirculation valve 26 is also a normally closed valve similar to the paint supply valve 25. Since the recirculation valve 26 is normally closed in this way, the paint flows into the recirculation block 30 through the recirculation valve 26 only when it is opened by air pressure. When the recirculation valve 26 is pneumatically opened, for example when no color paint is selected for this module, the paint passes through the common recirculation passage 41 and from there to a suitable conduit such as paint return conduit 67. The paint also reaches the return part through the and flows into the paint supply part of the color related to the module.

At this time, the paint return valve 27 is also in the normally closed position as shown in FIG. As a result, it is possible to prevent the paint of another selected color that returns through the universal type paint return manifold 14 from entering the return part of the non-selected paint controlled by the module of FIG. 3 as described later. To prevent. To this end, each of the return manifold blocks 29 comprises a check valve 70, which is shown schematically in FIGS. 2 and 3, by means of which the check valve 70 returns the return manifold block 29 and the paint. Paint between valve 27 and paint return manifold 14
It completely prevents you from returning to. As will be described later, when the paint return valve 27 is closed, the paint is enclosed between the seat of the paint return valve 27 and the check valve 70. Since the enclosed paint is incompressible, it holds the check valve 70 in the closed state so that the paint of any other color flows into the check valve 70 and the paint behind the check valve 70. For paint return manifold 14
To prevent inflow.

In FIG. 2, the paint supply valve 25 and the paint return valve 27 are normally closed. When the module color or type of paint in FIG. 2 is selected, both valves 25 and 27 will
The valve is opened by adding pressurized air to the expansion chamber below the working piston. At the same time this module recirculation valve
26 is discharged via the air inlet 66, whereby the return spring 73 of the recirculation valve 26 is brought into contact with the seat 75 of the recirculation valve 26 by a ball member 74.
To completely prevent the paint in the chamber 76 of the recirculation valve 26 from returning to the common recirculation passage 41.

This operation will be described. When a paint of a certain module is to be used in the paint application work, the paint flows into the paint inlet chamber 61 through the paint supply valve 25, and further the valve seat 57.
Through to the universal type paint supply manifold 13, and flows into a part 13a of the common manifold in the supply manifold block 28. Paint supply manifold 1
The paint flowing through the inside 3 flows out the port 17 at the end block 19 as shown in FIG.

Of course, in order to make the figure easier to understand, and to show how the used color paint flows in the corresponding module, the outlet and inlet leading to the paint application device are shown in FIGS.
In the figure, it is drawn roughly and at a 90 ° angle offset from the arrangement of FIG.

The paint flows from the paint supply manifold 13 to the paint applicator, but all the paint that has not been applied here is in the port.
Universal type paint return manifold via 18
Returned to 14. The paint flowing through the universal paint return manifold 14 fills the universal paint return manifold 14 and opens the check valve 70 in the return manifold block 29 of the module that controls the paint in use. After passing through the check valve 70, the paint in the open state at this time flows through the return valve 27 and the check valve 82 into the recirculation passage 41, from where it is returned to the paint supply unit in use.

Thus, the paint flow through the paint return valve 27 shown in FIG. 2 is excess paint that has not been applied by the paint applicator. In particular, while the applicator is in operation, a quantity of paint flows through the paint supply valve 25 into the system and the universal paint is actually applied without being returned to the return nidle 14. However, some of the paint will not be scorched in the system and the solids in the paint will be recirculated in the manner shown in the description of FIG. 2 so as to be kept in a floating state without settling. Returned to the supply section. If, for example, the applicator is closed, there will be some increase in paint flow through the module as shown in FIG. 2, but there will still be a recirculation flow that recirculates through the system. During this period, all other modules are closed by the paint supply valve 25 and the paint return valve 27, which are normally closed valves, and only the paint of the color being used is supplied to the paint supply manifold 13 and the paint return manifold 14. Filled with and flowing only the module of the selected color.

Check valve in manifold 14 for all paint return
Pressurize 70 and check valve of selected paint module
Only 70 is opened and the other non-return valve 70 is kept closed by the back pressure of the paint existing between it and its associated currently closed paint return valve 27.

When the paint is to be replaced with another color or another type of paint, the paint supply valve 25 and the paint return valve 27 are opened (opened) and closed, respectively, and the recirculation valve 26 is opened at the same time. Recycle the previously used color paint only through its module. After that, the solvent supply valve 45 is opened so that the solvent flows from all the upstream sides of the color module for color selection to the paint supply manifold 13, thereby causing the universal type paint supply manifold 13 and all of its downstream sides. Clean the conduit and applicator. This solvent then flows back through the port 18 and end block 20 to the paint return manifold 14 and then through the paint return manifold 14 to the module, i.e. all downstream points of the color selection device. The discharge valve 48 in the open state is reached, and from there, it is returned to the waste solvent tank (not shown). Thus, the entire system is washed with solvent and various color paints are recirculated through each module and its paint supply valve 25 and recirculation valve 26. After that, the solvent supply valve is closed. The air valve 50 is then opened, if necessary, to direct air through the common paint supply manifold 13 to the applicator gun, and through paint return manifold 14 to the discharge valve. This allows the entire system to be dried. While the air is being blown, the discharge valve 48 is held in an open state so that the air is discharged from the discharge valve, that is, the waste air valve. Even if the paint of the newly selected color is made to flow immediately after cleaning with the solvent, the solvent remaining in the system can be discharged from the discharge valve 48.

Each of the valves 25, 26, 27 within each module incorporates a check valve, such as check valves 80, 81, 82, as shown, respectively. These valves 80, 81, 82 completely prevent backflow of paint, solvent, etc., but are easily opened when valves 25, 26, 27 are opened to allow paint to flow in the correct direction.

Each valve 80, 81, 82 is defined such that the direction of its own paint working flow (paint flow for opening the valve) is the same as the opening operation direction of the spherical valve member 58. For example, the paint working flow through the valve seat 57 is in the downward direction, which means that the spherical valve member 58 causes the paint supply valve 25
Is the same as the closing direction. Thus these check valves
The valves 80, 81, 82 prevent the back pressure generated therein from opening the main spherical members of the valves 25, 26, 27, so that the valves 25, 26, 27 are opened, that is, the valves 25, 26, 27. It prevents the leakage of paint in the direction opposite to the normal direction.

The check valves 70 and 80 are extremely important to ensure that the paint colors of the two do not mix. For example, in a non-selected color module, the check valve 80 prevents the paint of another color in the paint supply manifold 13 from opening the paint supply valve 25 in the non-selected module to contaminate it. Is being prevented. When the paint return valve 27 of the non-selected module is closed, the paint of this module color is contained between the seat of the paint return valve 27 and the check valve 70. Since the enclosed paint is incompressible, the check valve 70 is kept closed and the paint return solvent 14 is prevented from entering another color paint or solvent. Thus, the check valves 70 and 80 ensure that the paint of the non-selective module is prevented from being contaminated.

Further, the paint contained in the module between the check valve 70 and the paint return valve 27 is first recirculated when the module is subsequently selected and the paint is passed through the paint return valve 27. Returned to the supply and then passed through the system to the applicator. As a result, the coating material is appropriately heated and the solid content is mixed before application.

The modules can be easily connected (laminated), that is, attached to each other, and can form respective universal supply and return manifolds. At the time of this module connection, a suitable groove or O-ring is provided at the end port of each module supply and return manifold block. Alternatively, the entire paint exchanger may be attached to a bracket such as the bracket B shown in FIGS. 2 and 5 and supported by a frame structure or an appropriate support structure.

For example, the valves such as valves 25, 26, 27 are connected to each other by suitable connecting means such as connecting screws S of the supply manifold block 28 and the return manifold block 29. For example, the paint supply valve 25 and the recirculation valve 26 can be connected to each other by means of a connecting block 31 and suitable screws (not shown) extending therethrough, as well as the return manifold block.
29 is connected to the paint return valve 27 by a connection block 36 and a screw (not shown). Also each color module 12
Can be connected to the basic paint exchanger 11 and the additional module by means of a connecting screw, such as the screw S shown in FIG.

FIG. 4 shows schematically the top of a valve 84 similar to valves 25, 26 and 27, which valve 84 is particularly suitable for use in, for example, high pressure airless paint spray systems. Valve 84 is identical to valves 25, 26 and 27 and is used in place of valves 25, 26 and 27 in each paint module for high pressure application. Valve 84 is a piston
It differs from the valve 25 and the like only in that an auxiliary spring 85 arranged above 86 is added, and this auxiliary spring 85 has the function of closing the normal spring (for example, the spring 65 in FIG. 2). I'm helping. More specifically, in a valve through which a high-pressure paint stream flows, even when air pressure is removed from the lower portion of the piston 86, the high pressure of the paint stream tends to keep the ball member away from the valve seat. . Therefore, an auxiliary spring 85 may be attached to the paint exchanger used in the high-pressure spray system so that the valve can be reliably closed when the control air is removed.

Each valve 25, 26, 27 has its own control air inlet port, such as the air inlet port 62 described for the paint supply valve. Such an inlet port corresponds to the inlet port 66 in the paint recirculation valve 26, for example. Although the inlet port 66 is shown in FIG. 1, it is omitted because it is not shown in FIGS. 2 and 3. Similarly, for a paint changer for color number 2, all return valves, such as paint return valve 27, are provided with a void inlet port, such as air inlet port 68b shown in FIG.

As can be seen from the above, the paint exchanger according to the invention is capable of using a number of different colors and suitable control means is provided for each valve of the various paint modules and the valve of the basic two-color or two-kind paint exchanger 11. Paint by adding to, for example, 1000 psi (pounds per square inch) or 70.3 kg / cm ²
With the above high pressure, paint of a specific color or type can be selectively supplied to the coating machine, and both non-selective paint and surplus of selective paint are recirculated to prevent overheating and sedimentation of solid matter. be able to.

Accordingly, the present invention provides a module type paint exchanger that selectively supplies paint to a plurality of applicators and constantly recycles the non-selected paint to the paint supply of the non-selected paint. By using the same paint module and the related parts of the universal supply and return manifolds, it is possible to easily paint a large number of colors and types on the basic paint exchanger with minimal piping and assembly. Both the selective paint and the non-selective paint can be recycled. Also, the pressure drop across the additional paint exchanger can be kept to a very low level by using a manifold block and by significantly reducing additional piping.

These and other advantages of variations and applications will be readily apparent to those of ordinary skill in the art without departing from the scope of the invention. Therefore, the invention is limited only by the claims.

[Brief description of drawings]

FIG. 1 is an exploded perspective view schematically showing a three-color color exchanger according to the present invention. FIG. 2 is a cross-sectional view of a single color module along line 2-2 of FIG. 1, showing paint flow passages of a selected color and paint flow shown in stippling. FIG. 3 is a schematic cross-sectional view similar to FIG. 2, but showing the paint flow passage and the paint flow shown in stipple when the paint color of this module is not selected. FIG. 4 is a schematic cross-sectional view of the valve actuator of the valve of FIG. 2 showing the spring used in a high pressure system. FIG. 5 is a schematic cross-sectional view similar to FIG. 2 taken along the line 5-5 of FIG. 1, showing a solvent cleaning device. 10 …… Paint exchanger, 11 …… Basic paint exchanger, 12 …… Color module, 13 …… Universal paint supply manifold, 14 …… Universal paint return manifold, 15,16 …… Block, 17, 18 …… Port, 19,20 …… End block, 25 …… Paint supply valve, 26 …… Recirculation valve, 27 …… Paint return valve, 28 …… Supply manifold block, 29 …… Return manifold Block, 30 …… Recirculation block, 70, 80, 81, 82 …… Check valve.

Claims (5)

[Claims] 1. A paint exchanger (10) for performing control for selectively introducing paints of different colors or components into a paint applicator, comprising a plurality of color module means (12), Each of the color module means (12) has a certain kind of color or composition of paint.
Is supplied to the paint coating machine by supplying it to the paint coating machine in order to return and circulate the one kind of coating material to the supply source of the one kind of coating material when not being supplied from the paint coating machine to the paint coating machine. Of the above-mentioned one kind of paint, a surplus portion which is not applied by the paint application machine is returned to the supply source of the one kind of paint and has a passage for circulation, and the plurality of color module means (12) Each has a portion of the supply tube (13a) and a portion of the return tube (14a), and when the plurality of color module means (12) are attached to each other, a portion of the supply tube (13a). And a part (14a) of the return pipe is configured to form one universal type applicator supply manifold (13) and one universal type applicator return manifold (14). Each of the color module means (12) has first, second and third valves (25, 26, 27) which are selectively operable, said first valve (25) being A flow of paint to a part (13a) of the supply pipe and a part (13a) of the supply pipe.
controlling the flow of paint from a) to the paint applicator, the third valve (27) controlling the flow of paint from a portion (14a) of the return pipe to the source of paint. Characteristic paint exchanger (10). 2. The first valve (25) comprises a normally closed paint supply valve, and when the normally closed paint supply valve is open,
A portion of the supply pipe (13
When the normally closed type paint supply valve is closed, the kind of paint is passed to a), and the kind of paint is returned to the second valve (26) and the kind of paint supply source for circulation. The paint exchanger according to claim 1, wherein: 3. The second valve (26) comprises a normally closed type circulation valve, and when the normally closed type circulation valve is open, the one type of paint is received from the first valve and the one type of The paint exchanger according to claim 2, wherein the paint exchanger is returned to the supply source of the paint and circulated. 4. The third valve (27) comprises a normally closed return valve, and when the normally closed paint supply valve and the normally closed return valve are simultaneously open, the third valve (27) is operated by the paint applicator. The surplus of the one kind of paint is received through a part (14a) of the return pipe, the surplus of the one kind of paint is returned to the supply source of the one kind of paint and recirculated, and the normally closed paint supply is performed. 4. The part (14a) of the return pipe is closed from the supply source of the kind of paint when the valve and the normally closed return valve are normally closed. Paint changer. 5. A check valve (70) is arranged between a portion (14a) of the return pipe and the normally closed return valve, and when the normally closed return valve is closed, the check valve is closed. 5. A paint exchanger according to claim 4, characterized in that a stop valve prevents backflow of paint into the part (14a) of the return pipe.