JPH0788409A - Flow rate control device - Google Patents

Abstract

PURPOSE:To obtain a stable paint emitting amt. regardless of the position of a spray gun in an automatic painting machine using an automatic apray gun and accompanied by the operation state diplacing the spray gun in a vertical direction. CONSTITUTION:An electropneumatic valve 130 of which the opening degree is adjustible corresponding to an electric signal is provided to the paint supply route reaching a spray gun 101 and a controller 150 receiving the position data of the spray gun 101 and determining the proper opening degree of the valve on the basis of the position data to issue the same to the electropneumatic valve 130 is provided. By this constitution, the difference generated in the paint emitting amt. per a unit time due to the position of the spray gun in a vertical direction, that is, the height thereof under the action of gravity can be suppressed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flow control device,
In particular, the present invention relates to a flow rate control device for stabilizing the paint discharge amount of a spray gun in an automatic coating machine such as a coating robot or a reciprocator that performs coating while moving a spray gun on an object to be coated.

[0002]

2. Description of the Related Art In automatic coating machines, the spray gun is often moved in the vertical direction in order to perform coating corresponding to an object to be coated. However, since an automatic coating machine generally has a form in which paint is supplied from a fixed paint supply source to a spray gun that is a movable part via a paint hose, etc. The amount of coating material discharged per unit time may differ depending on the position of the spray gun, that is, the height, and it may not be possible to keep the thickness of the coating film constant. The effect becomes more remarkable when a coating material having a high specific gravity is used. In the case of using a painting robot, conventionally, as a countermeasure, the moving speed is adjusted according to the height of the spray gun, that is, the moving speed is made smaller as the position becomes higher and the passing time at the position becomes longer. It was Also, in the case of a reciprocator equipped with a mechanism that can incline the spray axis of the spray gun with respect to the object to be coated,
This has been dealt with by operating the mechanism according to the height so that the spraying distance is adjusted.

[0003]

However, in such a measure, there is a possibility that a constant coating film cannot be maintained at the portion to be overcoated because the spraying pattern of the coating material changes with the change of the coating amount. is there. Further, there arises a problem that teaching or programming for adjusting the moving speed, or the configuration of the above mechanism or the control of its operating mechanism becomes complicated. An object of the present invention is to solve such a problem, to maintain a stable discharge amount regardless of the position of a spray gun, and to simplify the configuration and control of an automatic coating machine using a spray gun.

[0004]

To this end, the present invention provides
A flow rate control device provided in an automatic coating machine that performs coating while moving a spray gun to an object to be coated, which is arranged in a paint supply path leading to the spray gun and whose opening is adjusted according to an electric signal. It is provided with a possible electropneumatic valve and a control means for controlling the opening degree of the electropneumatic valve according to the vertical position of the spray gun.

[0005]

According to the present invention, since the valve opening is appropriately determined according to the position of the spray gun, the paint per unit time can be adjusted depending on the position of the spray gun in the vertical direction, that is, the height under the action of gravity. It is possible to suppress a difference in the discharge amount.

[0006]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the drawings. FIG. 1 shows an embodiment of an automatic coating machine to which the present invention is applied. Here, 100 is an automatic painting machine in the form of a painting robot, and painting is performed using an automatic gun 101. Automatic gun 1
01 is attached to a jig 105 at the tip of the robot hand 103, and is air for atomizing the paint from a compressed air source (not shown) (a central air for being introduced to the tip of the paint nozzle of the spray gun to atomize the paint). ) And injection pattern adjusting air (angular air introduced into the corner of the spray gun to determine the injection pattern) and the like, and the robot controller 1
Under the control of 10, the paint valve 13 from the paint source 120
The coating material supplied through 0 is jetted to coat the object to be coated. Here, the paint valve 130 can be in the form of an electropneumatic valve whose valve opening can be adjusted according to an electric signal. The robot control device 110 can set an operation control command for the robot 100 by teaching, programming, etc., and controls the operation of the robot 100 according to the setting contents, and also the position related to the operation control, that is, the robot hand 103 or the spray gun. It has a terminal capable of outputting information indicating the position of 101 and the like to the outside. Then, the controller 150 outputs a control signal for causing the paint valve 130 to adjust the valve opening degree based on the information.

The configuration of the controller 150 can be appropriately determined according to the forms of the robot controller 110 and the paint valve 130, signal standards, and the like. For example, if the robot controller 110 provides the above information in an analog amount, the paint valve 130 receives an analog amount of the control signal, and the controller 150 is configured by a microcomputer type device, the robot controller An interface having an A / D converter or the like for converting an analog amount signal presented by the device 110 into a digital amount, and a memory in which a reference table showing the relationship between the position and setting information for determining the valve opening is developed. , D / for converting the valve opening setting information read corresponding to the position from the reference table into an analog amount that the paint valve 130 can accept.
It may have an A converter and a CPU that controls them. Alternatively, in this case, if the position and the valve opening can be calculated using a predetermined calculation formula, the CPU does not have to execute the calculation each time,
It is also possible to replace the arrangement of the reference table. Further, instead of such a configuration centered on a microcomputer, the controller 150 can be configured using a digital or analog comparator or other arithmetic circuit. In any case, when the position Z of the spray gun and the discharge amount Q have a relationship as shown by the solid line in FIG. 2, for example, compensation is performed so that a stable discharge amount as shown by the broken line in the figure is obtained. Any device that outputs an electropneumatic valve control signal for

Regarding the setting of the value for the flow rate control performed by the controller 150, the controller 150 may perform the calculation each time based on the position information output from the robot control device to determine the control signal. Position information may be received at the time of teaching or programming, and calculation may be performed in advance according to the position information, or an appropriate value empirically determined according to the position may be input and expanded into a table. Also, the output timing of the electropneumatic valve control signal for determining the opening degree corresponding to the position can be appropriately determined in consideration of the responsiveness of the electropneumatic valve, and if the responsiveness is poor, for example, It is also possible to output a control signal corresponding to the position before the spray gun reaches the predetermined position. Further, although the controller 150 is provided separately from the robot control device 110 in FIG. 1, these may be integrated. In addition, in the above example, the case where the present invention is applied to an automatic coating machine in the form of a coating robot has been described.However, if the automatic coating machine that moves the spray gun vertically to the object to be coated, such as a reciprocator, Of course, the invention can be effectively applied.

[0009]

As described above, according to the present invention,
A stable discharge amount can be maintained regardless of the position of the spray gun, and the configuration and control of an automatic coating machine using the spray gun can be simplified.

[0010]

[Brief description of drawings]

FIG. 1 is a schematic view showing an embodiment of an automatic coating machine to which the present invention is applied.

FIG. 2 is a diagram for explaining the operation of the present embodiment.

[0011]

[Explanation of symbols]

 100 Painting Robot 101 Spray Gun 103 Robot Hand 110 Robot Control Device 120 Paint Supply Device 130 Paint Valve 150 Controller

Claims (1)

[Claims] 1. A flow rate control device provided in an automatic coating machine for performing coating while moving a spray gun with respect to an object to be coated, the flow control device being disposed in a paint supply path to the spray gun and responding to an electric signal. And a control means for controlling the opening of the electropneumatic valve according to the vertical position of the spray gun.