JPS6121757A - Controlling method of paint emitting amount in automatic painting by robot - Google Patents

Abstract

PURPOSE:To perform the control of a paint emitting amount with high accuracy, in performing the control of the paint emitting amount in the automatic painting by a robot, by correcting the response delay time of an operation part. CONSTITUTION:A robot mechanism 11 operates on the basis of the data stored in a robot control apparatus 2 by a robot signal control signal and performs the operation of a painting gun 13 along a desired locus. A control part 41 inputs a synchronous signal from the robot control apparatus 2, and regenerates and outputs preset and stored emitting amount data as an emitting amount control signal is synchronous relation to the operation of the robot mechanism 11 to control an operation part 42. By this method, the response delay in the alteration of the emitting amount is corrected and the control of the emitting amount is performed with high accuracy.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a method for controlling the amount of paint discharged in automatic painting by a robot. The method according to the invention is used for painting automobiles, etc.

Prior art, problems to be solved by the invention Conventionally, robots and
In paint discharge control in automatic painting by Soto,
A method for dealing with problems such as "sagging" and "sagging" by modifying the amount of paint discharged instead of modifying the robot motion trajectory, and a frequency related to the robot motion speed generated by a robot control device as a discharge amount control device for that purpose. A device has been proposed that counts the synchronization signals of −
12058.1).

In addition, conventionally, when setting and correcting discharge amount data,
Visually check the robot's movements.By manually operating a timing device that can generate binary signals, the output signal displays the cumulative count, making the operator aware of the relationship between the painted area and the cumulative count. Methods have also been proposed (for example, Japanese Patent Application No. 58-1 filed by the applicant).
59636 ``Automatic painting method and device using r robot'').

However, in general, in automobile painting equipment, there are various types of operating parts for adjusting the amount of paint discharged in response to some input signal, but no matter which one is used,
A time delay occurs between the input signal change timing and the ejection amount change timing as the output. For example, if a gear pump with rotational speed control is used as the operation unit, the accuracy in a steady state is high, but the response time is delayed by 1 to 2 seconds.

Furthermore, when an electro-pneumatic converter and an air-operated regulator are used, the accuracy is lowered, and although the response is excellent, a response delay of at least 0.2 seconds is required.

This means that the equipment installed inside the paint booth must be explosion-proof.
In the case of a gear pump method that requires an electric circuit for the gear pump motor, it must be installed in a remote location outside the paint booth, and in the case of a method that uses an electro-pneumatic converter and air-operated regulator, it must be installed at the source of the paint gun (painting The final actuator (near the gun) must be an air control device (eg, an air operated regulator), and therefore an electro-pneumatic converter must be provided. As described above, the requirement for explosion-proofness becomes a difficult point, and problems are unavoidable unless electrical control equipment with good responsiveness can be installed at the base of the coating gun.

Note that the response delay of 0.2 seconds for the air operated regulator may seem like a fast response, but when painting using a robot whose painting gun mounting part normally uses a speed of about 500 fl/sec, is about 100
This will result in a deviation of sm. In the first place, ``sauce'', ``
If you are trying to correct a defect such as "Skate" by correcting the discharge amount instead of correcting the robot trajectory, please refer to the following 10.
The deviation of 0 dragons is a value that cannot be overlooked.

An object of the present invention is to store the input/output response delay time of the operating section of the paint discharge control device in addition to the discharge amount data in a storage device provided inside the control section of the paint discharge control device, and to store the input/output response delay time of the operation section of the paint discharge control device. Based on the concept of outputting the discharge rate setting value corresponding to the discharge rate change timing at a timing earlier than the discharge rate change timing specified by the discharge rate data by the input/output response delay time, the response delay of the discharge rate change is The purpose is to perform correction and highly accurate discharge amount control.

Means for Solving the Problems In the present invention, the present invention consists of a series of paint discharge amount information and paint discharge amount switching timing information that are set and stored in advance in correspondence with synchronization signals from a robot control device used for robot control. The control unit in the paint discharge control device reads the discharge amount data in synchronization with the robot regeneration operation, controls the paint discharge control device based on the read data, and performs paint discharge based on the control. In addition to the discharge amount data, the input/output response delay time of the operating section of the paint discharge control device is stored in a storage device provided inside the robot, and during robot regeneration operation, the discharge amount change timing specified by the discharge amount data is stored. There is provided a paint discharge amount control method in automatic painting by a robot, which is characterized by outputting a discharge amount set value corresponding to the discharge amount change timing at a timing earlier by an input/output response delay time.

Embodiment FIG. 1 shows an apparatus for carrying out a method of controlling the amount of paint discharged in automatic painting by a robot as an embodiment of the present invention. The devices shown in FIG. 1 are a robot mechanism 11, a robot arm 12, a paint gun 13, a robot control device 2, and a paint discharge control device 4.
, a control section 41, an operation section 42, and a paint passage 5.

The robot mechanism 1 operates based on the data stored in the robot control bag N2 according to the robot control signal, and operates the coating gun 13 along a desired trajectory. The control unit 41 is
Input the synchronization signal 5(2) from the robot control device 2,
The discharge amount data set and stored in advance is regenerated and output as a discharge amount control signal S (41) in synchronization with the operation of the robot mechanism 11, and the flow rate of paint supplied to the coating gun 13 is controlled by controlling the operation section 42. is controlled, thereby controlling the paint discharge amount Q from the coating gun 13.

An example of the specific configuration of the operating section 42 in the device shown in FIG.
As shown in the figure. The operating section 42 includes an electropneumatic conversion device 42a, a paint reservoir 42b, a paint supply pump 42c, and an air operating regulator 42d. Note that the rotation speed of the gear pump may be controlled via a V/F converter.

Discharge rate data can be in various formats, but a set includes content that describes the discharge rate change timing in relation to a synchronization signal, and content related to the discharge rate control signal that should be output at that timing. , the data should be composed of multiple sets thereof.

In the apparatus shown in FIG. 1, the change timing of the control signal 5 (41) is corrected by taking into account the response delay time of the operating section 42. Various concrete methods can be considered depending on the synchronization signal 5(2) or the format of the ejection amount data.

Let me give you an example. As the synchronization signal 5(2), a pulse signal whose frequency changes in proportion to the regenerative operation speed of the robot mechanism 11 is used.
The discharge amount data Co=Un and the operation unit response delay time To are stored in the format shown in the figure.

The configuration of JAH (inside the control section 41 in the device shown in FIG. 1) is schematically shown in FIG. Among the data stored in the RAM shown in FIG. 3, data CO to Un consist of the synchronous pulse count cumulative number Co to Cn and discharge amount control data (generally current value signals) Uo to Un. last data T
o is response delay time data.

The ejection amount control data Un whose synchronous pulse count cumulative number corresponds to Cn is expressed as the ejection amount Qn (cc/m1n). In this way, the relationship between the robot operating position, that is, the application site, and the discharge amount is determined throughout the entire area during coating. Note that although the response delay time data TO is located at the end in the example of FIG. 3, it is not necessarily limited to this, and may be located at other positions.

Considering the background why this response delay time data To is required, in general, the control section 41 uses the discharge amount control signal S (4
1) is changed from one value to the next value, the actual change in paint flow rate occurs after To seconds. This fact is a problem with conventional methods. Ta.

In the apparatus shown in FIG. 1, the above-mentioned problem is solved by using response delay time data TO as shown in FIG.

The flow of the operation of the control section 41 in the apparatus shown in FIG. 1 is shown in FIG. X is synchronization pulse 5 from robot controller 2
Indicate the number of pulses in (2), and n indicates the application site number of the object to be coated. After setting x=Q, n-〇, if the start of the robot movement is determined, the timer is started, and if the input of the synchronization pulse is determined, X is incremented, and the result of time measurement by the timer is at time TO. A decision is made about something.

If the timer time is TO, the number of synchronizing pulses X up to the time of X is set as xo', this xo is stored, and the timer is reset.

Next, the number of synchronization pulses X is determined from the actual cumulative number of synchronization pulses Cn. is subtracted from the synchronous pulse integration at that point + I/1. x (=Cn), the ejection amount Qn corresponding to this Cn is read out, and the read out Qn is output. Then, increment n by 1.

Next, it is determined whether the robot's motion has stopped.

In other words, xo is the cumulative count of synchronous pulses when 10 seconds have elapsed from the start of robot operation, and after To seconds, rCn is used to detect the discharge rate change timing.
When xoJ matches the actual synchronous pulse cumulative count number X, a "yes" determination result is generated.

In the flowchart in Figure 4, the correction count number is calculated based on the correction time T at the start of robot regeneration operation, so even if the robot regeneration operation speed is changed due to a change in production tact, etc. There is no particular problem as long as it is reflected in the synchronization pulse frequency. That is, if the synchronous pulse cumulative count xo itself were to be stored, it would be affected by changes in production tact and would cause inconvenience, but this inconvenience can be prevented.

The flowchart shown in FIG. 4 is based on the assumption that the response delay time of the operation unit 42 is constant; however, in reality, the response time T varies depending on the amount of change in discharge amount ΔQ(-Q, ,Q- 1
>, that is, "r-f (Qn=i', , -,)" is generally used.

A flow diagram of the operation for this case is shown in FIG. In this case, the function f is stored instead of T0 in FIG. The flowchart in FIG. 5 is almost the same as the flowchart in FIG.
This differs from the third leap in that xO is obtained by multiplying by (n Q+, -+).

According to the experience of the present inventor, when an electro-pneumatic converter and an air-operated regulator are used in the operating section 42, the response changes depending on the sign of △Q and whether the Zunawaji discharge amount increases or decreases. It has been found that it is practical to set two types of time G, T(+) and T(-), and use these T(+) and T().

Effects of the Invention According to the present invention, when controlling the amount of paint discharged in automatic painting by a robot, it is possible to correct the response delay time of the operating section, and it is possible to control the amount of paint discharged with high accuracy.

[Brief explanation of drawings]

FIG. 1 is a diagram showing a device for controlling the amount of paint discharged in automatic painting by a robot as an embodiment of the present invention, FIG. 2 is a diagram showing the configuration of the operating section in the device shown in FIG. 1, and FIG. FIG. 1 is a diagram showing the storage status of data in the storage device of the control section of the apparatus, and FIG. 4 and FIG. 5 are both flowcharts showing the flow of the operation of the control section of FIG. 1. 11-robot mechanism, 12-robot arm, 13-painting gun, 2-robot control device, 4-paint discharge control device, 41-control unit, 42-operation unit, 5-paint passage.

Claims (1)

[Claims] 1. Synchronize the discharge amount data, which consists of a series of paint discharge amount information and paint discharge amount switching timing information, which are set and stored in advance in response to a synchronization signal from the robot control device used for robot control, with the robot regenerative operation operation. When controlling the paint discharge control device based on the read data and discharging paint based on the control, the discharge amount data is stored in a storage device provided inside the control section of the paint discharge control device. In addition, the input/output response delay time of the operation unit in the paint discharge control device is stored, and during robot regeneration operation, the discharge amount is changed at a timing earlier than the discharge amount change timing specified by the discharge amount data by the input/output response delay time. A method for controlling the amount of paint discharged in automatic painting by a robot, characterized by outputting a discharge amount set value corresponding to timing.