JPH0531407A - Liquid/powder paint-electrostatic painting controller - Google Patents

Abstract

PURPOSE:To obtain the liquid/powder paint-electrostatic painting controller which can be used in common by connecting in parallel an air flow switch and a terminal which can connect a trigger switch, operating a solenoid simultaneously with switching liquid and powder paints, and turning on a high-frequency generating circuit. CONSTITUTION:When a connecting shaft 16 is switched to a liquid electrostatic painting side, a first contact S1 is closed, a first and a second solenoids SOL1, 2 are turned on, and when blowing air is guided to an electrostatic painting gun 3A by operating a pump P, the pump P pressurizes a paint to saturation pressure and stops automatically. Subsequently, when the blowing air flows through by a trigger, an air flow switch FS detects it, relays R1, R2 are turned on, a high-frequency current of a high-frequency generating circuit HF is fed to the electrostatic painting gun 3A through a cord f2 and the paint is converted to electrostatic particles and blown. Also, when the connecting shaft 16 is switched, a second contact S2 is closed, air flows to a powder flow tank 8 by an opening/closing valve 12 and the paint is fluidized, and by supplying air to an air injector pump 7, powder elastrostatic painting can be executed.

Description

Detailed Description of the Invention

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a liquid and powder coating electrostatic coating control device which can be used for both liquid coating electrostatic coating and powder coating electrostatic coating.

[0003]

2. Description of the Related Art In recent years, in order to reduce the amount of dead air and blow back, and to improve the adhesion efficiency of the paint by the throwing effect to save the paint and to improve the production efficiency and the working environment, the electrostatic charge of the paint particles has been improved. An electrostatic coating method in which an attractive force is used to adhere to an object to be coated is widely used. On the other hand, powder coatings made of epoxy resin, acrylic resin, polyester resin, etc., eliminates various adverse effects of liquid coatings such as organic solvents, as well as robustness of coating film, ease of thick coating, pinholes, etc. It is widely used because it has few coating film defects and good edge coverage.

However, although the coating using this powder coating has the above-mentioned various advantages, it is difficult to adjust the colors, mix the colors, change the colors, have a high baking temperature, and make the beautiful finish rather difficult. For some reason, liquid paints using solvents such as organic solvents and water have been used before. Also in the case of this powder coating, as in the case of the liquid coating, electrostatic coating is adopted as one coating method, and the air spraying method of applying the coating using an electrostatic spraying gun that sprays the coating with air is It is often adopted as a flexible and simple coating method.

[0005]

However, although the liquid paint electrostatic coating and the powder paint electrostatic coating are common in that high pressure air and electrostatic are used, the structure of the spray gun itself is different, and In liquid paint electrostatic coating, the paint is pressure-fed using a pump such as a diaphragm or a plunger type, whereas in powder paint electrostatic coating, the powder is made into a fluid state by a powder flow tank by an air injector pump. Since many of the basic configurations, such as sending by using, are different, for liquid paint electrostatic coating and powder paint electrostatic coating,
Separate and independent ones were used as control devices, and commonality was not a consideration. In addition, liquid paint electrostatic coating and powder paint electrostatic coating are used differently depending on the application, and therefore the painter has to prepare two control devices for each, which is expensive and occupies a place. However, there was a problem to be solved such as maintenance of two devices and inferior usability.

The present invention has been completed as a result of finding out the common points of each apparatus between the liquid coating electrostatic coating and the powder coating electrostatic coating and making various studies on the sharing of the apparatus. An object of the invention is to provide a liquid paint electrostatic coating device, a liquid that can be commonly used for powder paint electrostatic coating, and a powder paint electrostatic coating control device.

Further, in the present invention, in the liquid paint electrostatic coating, the paint is turned on and off by using the trigger switch in the gun body and the air flow switch for detecting the air blown by the trigger operation. 2 with those that turn on and off
Although there are various types of electrostatic coating guns, the liquid and powder coating electrostatic coating control device of the present invention can use these two types of electrostatic coating guns for liquid coating electrostatic coating.

[0008]

SUMMARY OF THE INVENTION The present invention is directed to an air flow switch FS which operates by the flow of air blown to an electrostatic coating gun, and a trigger switch TS provided on the electrostatic coating gun.
A spray actuation line L1 in which a relay R is connected in parallel and a relay R is connected in series, and first contacts S1 and S1 which are turned on during liquid electrostatic coating, and the first contact S1. S1 is connected in parallel and the first contact S
A solenoid for turning on and off an air flow is connected in series to a changeover switch CS having, as an alternative, 1 and S1 and a second contact point which is turned on at the time of powder electrostatic coating.
A switching line L2 having a contact point turned on by the relay R is provided at the contacts S2, S2 of the above, and a liquid or powder coating static liquid to which a high frequency generator having a contact point turned on at the time of spraying by the relay R is connected. It is an electric painting control device.

[0009]

The electrostatic coating gun for liquid electrostatic coating has a trouble mainly due to the water-based coating that operates the solenoid of the control device by the trigger switch TS provided on the gun itself, and a spark due to the on / off of the switch. To prevent this, an air on / off valve is provided in the gun body, and the air flow switch FS in the control unit detects the air flow caused by opening the on / off valve by the trigger operation. Some are used for liquid paints.

In the spray operation line of the liquid / powder paint electrostatic coating control device of the present invention, a terminal to which the airflow switch FS and the trigger switch TS can be connected is connected in parallel. Either type can be used as it is.

Further, the switching line is provided with liquid paint electrostatic coating,
In addition to providing a changeover switch for changing electrostatic coating of powder paint, at the same time as changing over the changeover switch for electrostatic coating of liquid paint, the solenoid SOL is operated to send high-pressure air to the pump for feeding liquid paint and the electrostatic coating gun. Can be supplied and used.

In electrostatic coating of powder coating material, the solenoid SOL is activated by switching the changeover switch and operating the trigger switch TS by triggering the electrostatic coating gun to convey air to the powder flow tank. , It supplies powder metering air and enables spraying. In each case, the high frequency generation circuit is turned on with the operation of the solenoid SOL.

As described above, the liquid / powder paint electrostatic coating control device can be commonly used as a control device for liquid paint electrostatic coating and powder paint electrostatic coating.

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 schematically shows an embodiment of a liquid / powder coating electrostatic coating control device 1 together with a connection state when it is used as liquid coating electrostatic coating or powder coating electrostatic coating, and FIG. 2 shows its electric circuit diagram. 3 shows an example of an air system path connected to the solenoid SOL.

The liquid / powder paint electrostatic coating control device 1 has a spraying operation line L1 and a switching line L2, and comprises a main switch MS, a power lamp WL, and a step-down transformer T. A high frequency generation circuit HF is connected in parallel on the downstream side of the transformer T.

Further, as shown in FIG. 1, a high pressure air source C such as a compressor is connected to the liquid / powder coating electrostatic coating control device 1 together with a ground wire and an outlet.

Further, in the case shown in FIG. 1, an opening / closing valve 11 is provided in the box body 10 of the liquid / powder paint electrostatic coating control device 1.
Switching valves 12 and 13 having two outlet ports and a switching box 14 are arranged side by side, and the respective levers are integrally connected by a connecting shaft 16 so as to be integrated. 19 is provided.

In FIG. 1, the right side illustrates the connection state of each device for liquid paint electrostatic coating and the left side illustrates the connection state of each device for powder coating electrostatic coating, and electrostatic coating guns 3A and 3B are used respectively. In addition, in the case of liquid paint electrostatic painting, the paint tank 4 and
Pump P and are used.

In the case of powder coating electrostatic coating, the tank 6 is used.
A powder flow tank 8 provided with an air injector pump 7 above is used.

Further, the electrostatic coating gun 3A for electrostatic coating of liquid paint is, in this example, a gun for an organic solvent which is turned on and off by a trigger operation and has no trigger switch TS.
A trigger switch TS is provided on the electrostatic coating gun 3B for powder electrostatic coating, and the trigger switch TS is connected to the connector 17 via a cord a.

Further, the on-off valve 11 is connected to an inlet for the powder paint flowing air of the powder flow tank 8 through a flow path b such as a hose, and the outlet of each one of the switching valves 12 and 13. The ports are respectively connected to the carrier air intake port 7A and the powder metering air intake port 7B of the air injector pump 7 and flow paths c1 and d.
1 is connected.

Further, the carrier air supply port 7C of the air injector pump 7 is connected to the paint air intake port of the electrostatic coating gun 3B via the flow path e. Air injector pump 7
A well-known one that uses a combination of a nozzle and a Venturi insert can be used, and a well-known one that uses an automatic valve for opening and closing the paint at the paint inlet can also be used by controlling it using a relay of an electric circuit. ..

Further, the connector 17 of the switching box 14 is connected with a cord f1 leading to a high voltage electrostatic circuit (not shown) provided in the electrostatic coating gun 3B. Like the connector 19, the connector 17 is a multi-core type connector in which the cords a and f1 are simultaneously divided and connected.
When the electrostatic coating gun 3A has a trigger switch, it is similarly connected to the connector 19.

Regarding the liquid paint electrostatic coating, the other outlet ports of the switching valves 12 and 13 are connected to the pump P and the blowing air inlet of the electrostatic coating gun 3A through the flow paths c2 and d2. It The pump P is a diaphragm pump,
A plunge pump, a gear pump or the like can be used, and the pump P sucks the paint from the paint tank 4 and feeds it to the paint intake port of the electrostatic painting gun 3A via the flow path g. A high voltage electrostatic circuit (not shown) of the electrostatic coating gun 3A is connected to the connector 19 via a cord f2.

The open / close valve 11 and the switching valves 12 and 13 are
As shown in FIG. 3, connected to the high-pressure air source C, and between the on-off valve 11, the switching valves 12, 13 and the high-pressure air source C, display units 21, 22, 23 are provided. A metering valve 31, 32, 33, which can be adjusted by means of the knobs 24, 25, 26 in FIG. 1, is connected. Further, in this embodiment, as the solenoid SOL, two first solenoids SOL are used.
The first and second solenoids SOL2 are used, the switching valve 12 is provided with the first solenoid SOL1, and the switching valve 13 is provided with a detection portion of the airflow switch FS and a second solenoid.
Of the solenoid SOL2.

The first and second solenoids SOL1 and S
OL2 is arranged on the switching line L2 of the electric circuit of FIG. In the switching line L2, first contacts S1 and S2 that are turned on during the liquid electrostatic coating and second contacts S2 and S2 that are turned on during the powder electrostatic coating are connected in parallel, and are connected in parallel. The first and second solenoids SOL1 and SOL2 are connected in series.

Further, the first and second contacts S1, S1, S
The switches S and S2 are selectively turned on to form a changeover switch CS for switching between liquid electrostatic coating and powder electrostatic coating, which is housed in the switching box 14 and can be switched by the lever. Is configured as follows.

The second contact S2 for electrostatic powder coating is also provided.
A contact r1a0 of a relay R1 provided in the spray operation line L1 is interposed in S2, and in this embodiment, the relay R1 and another relay R2 are used as the relay R.

The spray actuation line L1 connects in parallel the contacts of the airflow switch FS and the terminals SO, SO to which the trigger switch TS can be connected using the cord a, and the respective spray connections are connected in parallel. Display lamp OL that lights up when attached, and the relays R1 and R2
And are connected in series.

Further, as described above, on the downstream side of the transformer T,
A high-frequency generation circuit HF that is turned on and off by contacts r1a1 and r2a1 of the relays R1 and R2 is connected, and this output is output from the connectors 17 and 19 to a high-voltage electrostatic circuit of the electrostatic coating guns 3A and 3B (Fig. (Not shown) via cords f1 and f2. The high frequency generation circuit HF can be adjusted by the knob 40, and its value is displayed on the display unit 41.
Is displayed.

Next, the operation of the device 1 will be described. Connecting shaft 16
To the liquid electrostatic coating side, the first contacts S1, S
1 is closed, and the first and second solenoids SOL1 and SOL2
Immediately turns on, operates the pump P, and conducts blowing air to the electrostatic coating gun 3A.

The pump P automatically stops when the paint is pressurized to a predetermined saturation pressure. When the trigger is operated in this state, the blowing air first flows through. This is detected by the airflow switch FS, the relays R1 and R2 are turned on, and the high-frequency current of the high-frequency generation circuit HF is sent to the electrostatic coating gun 3A via the code f2, and is discharged by the subsequent pulling of the trigger. The paint is converted into electrostatic particles and sprayed.
By releasing the trigger, the paint is first cut off, and then the blowing air is stopped, and when the airflow switch FS detects this, the relays R1 and R2 are opened and the high frequency current is cut off.

Also, the electrostatic coating gun 3A has a trigger switch T.
The same applies when S is included.

Next, when the connecting shaft 16 is switched to the electrostatic coating side for powder coating, the second contacts S2, S2 are closed. Further, air for powder flow flows into the powder flow tank 8 by the open / close valve 12 to fluidize the paint. Next, when the trigger is pulled, the trigger switch TS is turned on and the relays R1 and R2 are operated, so that the contact r1a0 causes the first and second solenoids S to operate.
The OL1 and SOL2 are closed, and the carrier air and the powder metering air are supplied to the air injector pump 7. Thereby, the flow path e
From the powder by closing the contacts r1a1, r2a1
The electrostatic coating gun 3A discharges the particles while forming them into electrostatic particles, which enables powder electrostatic coating.

In the apparatus of the present invention, the electrostatic coating guns 3A, 3B, the pump P, the powder flow tank 8, the air injector pump 7 and the like may be known ones, and air cleaners, paint pressure regulators and the like may be used. Equipment and parts are also used as needed. Furthermore, it is possible to switch using a switch instead of the connecting shaft, reduce the number of ports connected to each hose, and change the connection of the hose and cord to liquid paint electrostatic coating or powder paint electrostatic coating. Along with the switching, various modifications can be made such as automatically setting the air pressure and air amount suitable for liquid paint electrostatic coating and powder paint electrostatic coating.

[0036]

As described above, the liquid / powder coating electrostatic coating control device of the present invention can be commonly used for liquid coating electrostatic coating and powder coating electrostatic coating, which can reduce the cost of the device and enhance the usability. ..

[Brief description of drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention together with a connected state.

FIG. 2 is a diagram showing an example of an electric circuit.

FIG. 3 is a diagram showing an example of a connected state of solenoids.

[Explanation of symbols]

 3A, 3B Electrostatic coating gun 7 Air injector pump 8 Powder flow tank CS changeover switch FS Airflow switch TS Trigger switch P Pump

Claims (1)

Claims: 1. Terminals SO, SO capable of connecting an air flow switch FS that operates by the flow of blowing air to an electrostatic coating gun and a trigger switch TS provided on the electrostatic coating gun.
Is connected in parallel and the relay R is connected in series, and the first contact points S1 and S1 which are turned on during electrostatic coating of the liquid paint, and the first contact points S1 and S1 are connected in parallel and A solenoid for turning on and off an air flow is connected in series to a changeover switch CS having a first contact S1, S1 and a second contact which is turned on when powder coating electrostatic coating is applied. Electrostatic liquid or powder coating comprising switching lines L2 having contacts S2 and S2 which are turned on by the relay R, and a high frequency generator connected through contacts which are turned on at the time of spraying by the relay R Painting control device. [0001]