JPH0317955Y2 - - Google Patents

Description

[Detailed description of the invention] <Industrial application field> The present invention is applicable to the air pressure control of a paint sprayer, for example, the pressure control of compressed air that atomizes paint in an electrostatic sprayer. ) In an electrostatic coating machine, it relates to a pneumatic control device for a coating machine used to adjust the shaping pressure of atomized paint.

<Prior art> Conventionally, a mechanism combining an air-operated valve, a solenoid, an air pressure regulator, etc. is connected between an electrostatic sprayer, etc. and an air source, and is used as a pressure control device for the air sent to the sprayer. has been done. For example, air from an air source is adjusted to a predetermined pressure with a pneumatic regulator,
A mechanism is often used in which an air-operated valve is opened and closed by the operation of a solenoid to supply or stop the supply of pressure-regulated air to an electrostatic sprayer.

<Problems to be solved by the invention> By the way, in general, when mass producing multi-color painted products or multi-layer painted products using paints of various colors and types, the specific gravity, polarity and Since the electrical resistance and the like are different from each other, it is required to be able to continuously change the pressure of the air supplied to the coating machine so as to correspond to the characteristics of each coating material. Insufficient control of this air pressure may cause uneven coating thickness, poor shaping, uneven coating color, etc., and may also affect the aesthetic appearance, weather resistance, corrosion resistance, abrasion resistance, etc. of the coating film. But it becomes a problem. Further, the same thing as above is required when continuously painting a group of objects to be painted having various shapes.

However, in many conventional air pressure control devices of this type, it is possible to control the supply air at a constant pressure only at one or two or three types of air pressure values; In order to carry out continuous conversion control, it was necessary to construct an air pressure control device 1a as shown in FIG. 3, for example.
The control device 1a shown in the figure includes a coating machine 7 and an air source 8.
Six air operated valves 10a to 10f and six air pressure regulators 11a to 11f are arranged in parallel as a set of operating valves and regulators, and six solenoids 12a to 12f are arranged between them. Air operated valve 10a~
10f, respectively, and the air pressure regulators 11a to 11f are connected to the air pressure regulators 11a to 11f in advance, for example, 1Kg/cm ² , 2Kg/cm ² ,
It is set to maintain six types of air pressure values: 3Kg/cm ² , 4Kg/cm ² , 5Kg/cm ² , and 6Kg/cm ² , and the air operated valves 10a to 10f are opened and closed by solenoids 12a to 12f during painting. By changing the timely manner according to the type of object to be painted, for example, the car model,
Painting can be performed continuously while changing air pressure values in six levels as needed.

However, in the recent automobile painting process, in addition to the increase in car models and the number of parts, the shapes of objects to be painted and the required paint colors have become more diverse, so there are dozens of levels of air pressure values. There is a need to be able to convert and control the pressure of the supplied air, and in order to meet this demand, the conventional air pressure control device described above requires an air-operated valve 10 and an air pressure regulator. It is necessary to prepare dozens of combinations with 11, etc., and the entire device becomes extremely large-scale. In other words, none of the conventional control devices can sufficiently handle the conversion control of the supply air pressure between many levels of air pressure values.

The present invention was developed in consideration of the above-mentioned actual situation, and its purpose is to continuously convert the pressure of air supplied to the paint sprayer between multiple pneumatic pressure values. The purpose of the present invention is to provide a pneumatic control device for a coating machine that is very small in scale.

<Means for solving the problem> The air pressure control device for the paint sprayer of the present invention consists of an air pressure regulator that is connected to an air source and adjusts the air to a predetermined pressure, and a multi-level value for each value. a control circuit that outputs an electric signal that outputs an electric signal; and the control circuit is connected to the air pressure regulator and the coating machine, respectively, and adjusts the air pressure from the air pressure regulator to an air pressure value corresponding to the step value indicated by the electric signal. Convert to
The apparatus is characterized by being equipped with an electric/pneumatic converter that sends air at the converted pressure to the coating machine.

The electrical/pneumatic converter used in the present invention may be a single converter that converts a certain pneumatic pressure value into a desired pneumatic pressure value that directly corresponds to the semantic content of the electrical signal by a single conversion operation. However, by performing two conversion operations, a certain pneumatic pressure value is first converted to an appropriate pneumatic pressure value while maintaining the correspondence with the meaning and content of the electric signal, and then the original pneumatic pressure value is changed according to this converted pneumatic pressure value. More preferably, it consists of two converters that convert the air pressure into a desired pneumatic pressure value. This is due to the following reason. Generally, if the electric/pneumatic converter and control circuit used in this invention are installed near an electrostatic sprayer, various adverse effects (malfunction, etc.) may occur due to the high voltage and high current used in the sprayer. becomes easier to receive. on the other hand,
If the converter of the present invention is installed at a location remote from the electrostatic coating machine, a time lag generally occurs and the responsiveness of air pressure conversion deteriorates. Therefore, a converter that performs pneumatic pressure/pneumatic pressure conversion according to the meaning of the electrical signal is installed in a location away from the electrostatic coating machine, and a converter that performs pneumatic pressure/pneumatic pressure conversion according to the above converted pneumatic pressure value is installed in a static location. This is because by installing it near the electric coating machine, it is not affected by the adverse effects of the high voltage and high current used in the coating machine, and high responsiveness of air pressure conversion can be obtained.

(Function) The air pressure control device of the present invention controls the air supplied from the air source to the paint sprayer to have a multi-level pressure value of, for example, ²⁵ to 28 different types of electric signals (for example, bit signals). ) can be converted continuously according to

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

The pneumatic control device 1 of the embodiment shown in FIG. A pneumatic pressure regulator 3 (precision regulator) and an electric/pneumatic converter 5 are arranged in the route, and another electric/pneumatic converter (variable ratio relay) 6 is arranged at the branch point on the paint machine side of the two routes. It will be done. Moreover, the electric/pneumatic converter 5 is
It is connected to the control circuit 4.

The air pressure regulators 2 and 3 are connected to an air source 8, e.g.
It is preset to constantly and precisely adjust the pressure of 10 Kg/cm ² to 7 to 10 Kg/cm ² and 1 to 2 Kg/cm ² , respectively. The control circuit 4 is equipped with a microcomputer, etc., and when an operator inputs a signal specifying a specific step among 2 ⁵ (32) to 2 ⁸ (256) steps into the signal input section of the circuit, the control circuit 4 selects the specified step. The electrical signal that means electrical/pneumatic converter 5
It is now output to .

Further, the electric/pneumatic converter 5 is connected to the pneumatic regulator 3
In response to an electrical signal from the control circuit 4, the pressure of the air is converted into a pneumatic pressure value corresponding to the step value meant by the signal. That is, the converter 5 has a power output of 0 to 1 (or 2) kg/kg depending on the type of electrical signal.
Produces air with pressure values in 2 ⁵ to 2 ⁸ steps in the cm ² range.

Further, the electric/pneumatic converter 6 converts pneumatic pressure values in ^2-5 to ^2-8 steps (range of 0 to 1 (or 2) Kg/cm ² ) adjusted by the electric/pneumatic converter 5.
7 to 10 determined by air pressure regulator 2, depending on
The air pressure value of Kg/cm ² is converted into a pressure value of each desired stage (in the range of 0 to 7 or 10 Kg/cm ² ), and the air having the pressure value is sent to the cup-type atomizer 7.

Therefore, the control device 1 of the embodiment
It is possible to convert the pressure of the supplied air into 2 ^to 2 ^{to 8} steps, and depending on the shape of the object to be painted, the type and color of the paint, etc., the operator can send a signal representing the desired step to the control circuit 4. Air is sent to the coating machine 7 at a pressure value that corresponds to the shape of the object, paint color, etc., by inputting a timely conversion into the control circuit 4 or by automatically operating the control circuit 4 according to pre-made programming. Numerous micro holes 9...(second
As a result, particle formation and shaping of the paint can be carried out very smoothly. Even if the present control device 1 is connected to another electrostatic atomizer 7a or the like instead of the cup-type atomizer 7, the same effects as described above can be obtained.

<Effects of the invention> As explained above, the air pressure control device for a paint sprayer of the present invention can convert and adjust air at multiple pressure values according to the input information of the control circuit. by automatic or manual control,
Appropriate coating according to the shape and type of the object to be painted, color, polarity and type of paint, etc., that is, uniform coating without unevenness, regardless of individual differences among workers, is possible, and it is also possible to make the paint fine particles. The coating area during atomization and shaping can be controlled more smoothly, and a coated product with excellent coating film aesthetics, weather resistance, corrosion resistance, and abrasion resistance can be obtained. Moreover, in the control device of the present invention, the entire device can be extremely small-scale, and it is easy to increase or decrease the number of air pressure stages, and there is no need to increase the scale of the device in accordance with the increase or decrease.

[Brief explanation of the drawing]

Fig. 1 is a diagram showing an air pressure control device according to an embodiment of the present invention, Fig. 2 is a perspective view showing a coating machine connected to the device in Fig. 1, and Fig. 3 is a diagram showing a conventional air pressure control device for painting. It is a diagram. In the figure, 1... pneumatic control device, 2, 3... pneumatic regulator, 4... control circuit, 5, 6... electrical/pneumatic converter, 7, 7a... painting machine, 8... air source .

Claims (1)

[Claims for Utility Model Registration] An air pressure regulator that is connected to an air source and adjusts the air to a predetermined pressure; a control circuit that outputs electrical signals representing multi-level values; and the control circuit. , connected to the air pressure regulator and the coating machine, respectively, converting the air pressure from the air pressure regulator into an air pressure value corresponding to the step value indicated by the electric signal;
A pneumatic control device for a coating machine, comprising an electric/pneumatic converter that sends air at the converted pressure to the coating machine.