JP2000005659A - Coating robot - Google Patents

Abstract

PROBLEM TO BE SOLVED: To improve cleaning efficiency at color change. SOLUTION: A coating robot 11 has the second arm 16 which extends horizontally from the upper end of the first arm 15 and swings around a shaft C. A coating supply route 21 for supplying a coating supplied from a coating supply source to a coating gun 18 and a bypass route 22 which bypasses the route 21 are formed on the upper surface of the second arm 16. The bypass route 22 is formed to bypass a coating pump 25 arranged downstream from a color change valve unit 23 and a flow meter 26, its one end is connected to an upstream side three-way valve 24 and the other end is connected to a downstream side three-way valve 27. Therefore, thinner is circulated between the upstream side valve 24 and the downstream side valve 27, and the coating supply route 21, pump 25, and the flow meter 26 are cleaned preliminarily in order to improve cleaning efficiency.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a painting robot configured to effectively wash paint in a paint supply line formed along a robot arm.

[0002]

2. Description of the Related Art For example, in a painting process for painting a work surface by a painting robot, when a work is conveyed by a conveyor, the painting robot performs a predetermined painting operation in accordance with a painting program preliminarily taught. That is, when the work arrives at the work area, the painting robot automatically starts the painting work and ends the predetermined painting work before the work passes through the work area. And
When the predetermined painting operation is completed, the painting robot turns the arm to return to the painting start position.

[0003] In a coating system that automatically performs a coating operation using a coating robot as described above, the color of the paint is specified by the work, and when the coating color of the work is switched, the work is transferred in conjunction with the transfer of the work. The so-called color change is performed. Further, the painting robot is configured to selectively supply one kind of paint from a plurality of paints to a painting gun mounted on the tip of the arm via a paint supply system formed along the arm. In addition, a color changing valve unit is provided in the paint supply system. Note that the color changing valve unit may be configured to be mounted on an arm of a painting robot, or may be installed at a location other than the arm (for example, a base or a position near the robot).

[0004] In this color changing valve unit, a plurality of valves to which a plurality of paint tubes each having a different color and extending from each paint supply source are connected are connected in parallel to the manifold. The paint tube, air tube, and thinner tube drawn out from the discharge side of the manifold of the color changing valve unit are arranged so as not to hinder the operation of the wrist and connected to the paint gun.

[0005] As described above, a paint supply system comprising a paint tube communicating between the paint gun and the color changing valve unit is provided with a pump for pressurizing the paint supplied from the color changing valve unit and discharging the paint to the coating gun. Equipment such as a flow meter is provided. In the coating robot provided with the color changing valve unit as described above, the space between the color changing valve unit and the coating gun is washed with a cleaning liquid such as thinner when performing color changing. The paint supply line, the pump and the flow meter between the color changing valve unit and the paint gun perform a number of washing operations in which thinner and air for purging the thinner are alternately supplied until the last residual paint is removed. Repeated times.

[0006]

However, in the painting robot performing the cleaning operation as described above, the cleaning operation must be performed after the coating gun is discarded and moved to the blowing position. There is a problem that time is delayed. Also, during the cleaning operation, the inside of the pump and other equipment is complicated and difficult to clean, so the number of cleanings increases, and the paint remaining in the paint supply system and the pump and other equipment is alternated between thinner and air for a predetermined time. Since the cleaning is performed by supplying the thinner, the amount of thinner used increases accordingly.

Accordingly, an object of the present invention is to provide a painting robot which has solved the above-mentioned problems.

[0008]

In order to solve the above problems, the present invention has the following features. Claim 1
According to the invention described above, in a painting robot configured to supply paint through a paint supply system to a painting gun attached to a tip of an arm, a pump is provided in the paint supply system, and one end is provided by the pump. A bypass system is provided which is connected to the paint supply system upstream and has the other end connected to the paint supply system downstream of the pump.

Therefore, according to the first aspect of the present invention, the bypass system has one end connected to the paint supply system upstream of the pump and the other end connected to the paint supply system downstream of the pump. The paint remaining in the paint supply system is circulated through the bypass system together with the thinner supply before the paint gun moves to the throw-off position during color change, and the paint inside the painting equipment such as pumps is complicated and difficult to clean. Can be washed. Thus, the cleaning time can be reduced, and the number of times of cleaning can be reduced.

The invention according to claim 2 is the painting robot according to claim 1, wherein the pump comprises:
When the paint supply line and the pump itself are subjected to the cleaning process, a forward rotation operation and a reverse rotation operation are alternately performed so that the cleaning liquid circulates through the bypass line.

According to the second aspect of the present invention, when cleaning the paint supply system and the pump itself, the normal rotation operation and the reverse rotation operation are alternately performed so that the cleaning liquid circulates via the bypass system. Therefore, at least the paint remaining in the paint supply system and the pump can be efficiently washed, and the number of washings can be reduced, and the amount of thinner used can be reduced.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a side view showing the configuration of an embodiment of the painting robot according to the present invention. As shown in FIG. 1, the painting robot 11 is installed in a painting area where a painting operation is performed. In the painting area, a work (object to be painted) is moved at a constant speed by a conveyor (both not shown). Supplied with.

The painting robot 11 is a playback-type articulated robot that performs a painting operation pre-teached when a workpiece is conveyed. Painting robot 11
Generally includes a base 13, a turning base 14 that turns around the A axis on the base 13, a first arm 15 that stands on the turning base 14 and swings around the B axis, and a first arm 15. Second arm 1 extending horizontally from the upper end and swinging about the C axis
6 and a wrist 17 provided at the tip of the second arm 16 and rotating around the D, E, and F axes.

A coating gun 18 is attached to the tip of the wrist 17. The painting gun 18 moves to a predetermined painting height position by swinging of the first arm 15 and the second arm 16, and the paint spraying direction is changed by the operation of the wrist 17. In the coating robot 11 configured as described above, each movable portion is driven by a motor (not shown) to adjust the position and the coating direction of the coating gun 18, and each motor serves as a control device. The turning base 14, the first arm 15,
The second arm 16 and the wrist 17 are controlled to be driven. An encoder (not shown) for detecting the angle of each movable part is incorporated in each joint part of the painting robot 1, and a rotation position detection signal of each movable part is fed back to the robot controller 20. Is done.

On the upper surface of the second arm 16, a paint supply system 21 for supplying paint supplied from a paint supply source (not shown) to the coating gun 18, and a bypass system for bypassing the paint supply system 21 are provided. 22 are provided. In the paint supply system 21, a color change valve unit 23, an upstream three-way valve 24, a paint pump 25 for controlling the flow rate of paint, and a flow rate discharged from the paint pump 25 are sequentially measured from the upstream side. Each coating device including a flow meter 26 and a downstream three-way valve 27 is provided.

The bypass system 22 is provided so as to bypass the paint pump 25 and the flow meter 26 disposed downstream of the color changing valve unit 23, and one end thereof is connected to the upstream three-way valve 24. The other end is a downstream three-way valve 27
It is connected to the. FIG. 2 is a system diagram showing the configuration of the paint supply system. As shown in FIG. 2, the robot controller 20 controls the painting robot 11 and the painting gun 18, the color changing valve unit 23, the upstream three-way valve 24, the paint pump 25, the flow meter 26 based on a command from the host computer 30. The drive control of the downstream three-way valve 27 is performed.

The color changing valve unit 23 operates to selectively supply one specified paint from a plurality of paints supplied from a paint supply source (not shown) to the coating gun 18. And has a plurality of air operation valves 31a to 31h. Air operation valve 3
1a to 31f are paint valves to which a paint tube 33 is connected. Also, the air operation valve 31
g is a thinner valve to which a thinner tube 34 is connected. The air operation valve 31h is an air valve to which an air tube 35 is connected.

Each air operation valve 31a
31h are configured to be opened by air signals supplied by opening and closing operations of the electromagnetic valves 32a to 32h. Therefore, the robot controller 20 controls the coating robot 11
Each solenoid valve 32a ~ according to the type of work to be painted
By selectively opening the valve 32h and controlling the opening and closing of the air operation valves 31a to 31h, the paint of any designated color is supplied to the coating gun 18.

The air operation valves 31g and 31h are alternately opened at predetermined time intervals during the color change processing, and wash and remove the previous residual paint. The upstream three-way valve 24 and the downstream three-way valve 27 are switching valves having an inflow port a, a diversion port b, and an outflow port c, respectively. Normally, the upstream three-way valve 24 and the downstream three-way valve 27 communicate with the inflow port a and the outflow port c, respectively.
The downstream three-way valve 27 switches so as to communicate the inflow port a and the branch port b.

Thus, the paint supply line 21 and the bypass line 22 are connected to the upstream three-way valve 24 and the downstream three-way valve 27.
And a communication state is established. In this communication state, the paint pump 2
When 5 is driven, the thinner circulates through the paint supply line 21 and the bypass line 22 to clean the inside of the paint supply line 21, the paint pump 25, and the flow meter 26. Therefore, the cleaning efficiency at the time of performing the color change processing by moving the coating gun 18 to the discarding and blowing position can be increased, and the number of times of cleaning can be reduced.

FIG. 3 is a block diagram showing the configuration of the robot controller 20 and each device. As shown in FIG. 3, the robot controller 20 has a CPU 36,
The CPU 36 includes a ROM 37, a RAM 38, and a servo amplifier 4 for driving a servo motor 39 for driving the robot.
0, a servo amplifier 42 that drives a servo motor 41 of the paint pump 25, an A / D converter 43 that A / D converts a flow signal transmitted from the flow meter 26, and an i / o module 44. ing. Also, i / o module 4
4, the solenoid valves 32a to 32h, the coating gun 18, the upstream three-way valve 24, and the downstream three-way valve 27 are connected.

The ROM 37 stores the CPU 3 as described later.
6 stores a control program to be executed. Therefore, the CPU 36 performs a coating control process, a color change process, a cleaning process, and the like based on the control program. FIG. 4 is a flowchart of the control process executed by the CPU 36. As shown in FIG. 4, the CPU 36 determines in step S
Until there is a cleaning operation instruction from the host computer 30 at 11 (hereinafter "step" is omitted), the painting operation is continued at S12. In S11, when there is a cleaning work instruction from the host computer 30, the flow proceeds to the cleaning work in S13 and thereafter.

In S13, the paint pump 25 is stopped, and the discharge of the paint from the paint gun 18 is stopped. Next S1
In step 4, the painting robot 11 is operated to operate the painting gun 18.
And start moving to the blowing position. Subsequently, S15
Then, the downstream three-way valve 27 is connected to the inflow port a and the branch port b.
Switch to communicate with. In the next S16, the air operation valve 31g, which is a thinner valve of the color changing valve unit 23, is opened to supply the thinner to the paint supply system path 21. In S17, the paint pump 25 is driven to fill the thinner into the bypass passage 22.

In the next step S18, the paint pump 25 is driven until the thinner fills the bypass passage 22. Then, when thinner is filled in the bypass system passage 22, S19
Then, the paint pump 25 is stopped. In S20, the upstream three-way valve 24 is switched so that the branch port b and the outflow port c of the upstream three-way valve 24 communicate with each other. Then, S
At 21, the paint pump 25, the flow meter 26 and the bypass system 2
The thinner filled in 2 is circulated.

Accordingly, after the thinner moves in the forward rotation direction of the paint pump 25 for a predetermined time, the bypass system 22 and the paint supply system 21 formed between the upstream three-way valve 24 and the downstream three-way valve 27 are formed. , The paint pump 25 moves in the reverse rotation direction. In this way, the thinner filled in the bypass system passage 22 and the paint supply system passage 21 reciprocates, whereby the insides of the paint pump 25 and the flow meter 26 having complicated internal structures are cleaned.

In the next step S22, it is confirmed that the painting robot 11 has moved the painting gun 18 to the discarding position. When the paint gun 18 is completely moved to the discarding position, S
Proceeding to 23, the drive of the paint pump 25 is stopped. Then, in S24, the downstream three-way valve 27 is switched so that the inflow port a and the outflow port c of the downstream three-way valve 27 communicate with each other, and the inflow port a and the outflow port c of the upstream three-way valve 24 are communicated. The upstream three-way valve 24 is switched as described above.

Next, at S25, the color changing valve unit 2
Air operation valve 31, which is an air valve of No. 3
h is opened to supply air to the paint supply system path 21. Further, at S26, the paint supply system 21
The thinner and the paint filled in are discharged and the spraying is performed. Thus, the paint remaining inside the paint pump 25 and the flow meter 26 is purged together with the thinner.

In S27, the downstream three-way valve 27 is switched so that the branch port b and the outflow port c of the downstream three-way valve 27 communicate with each other, and the inflow port a and the branch port b of the upstream three-way valve 24 are communicated. So that the upstream three-way valve 2
Switch 4. As a result, the paint and thinner remaining in the bypass passage 22 are discharged from the paint gun 18 and purged.

When the purge of the bypass system passage 22 is confirmed in S28, the process proceeds to S29, in which the valve of the designated color among the paint air operation valves 31a to 31f of the color changing valve unit 23 is opened and the next time. Switch to paint for painting. Then, in S30, the painting robot 11
Start painting. In this way, the thinner is removed from the upstream three-way valve 24 and the downstream three-way valve 27 before the waste blowing process is performed.
Between the paint supply line 21 and the paint pump 2
5. The cleaning efficiency can be increased by pre-cleaning the inside of the flow meter 26. Therefore, it is possible to reduce the number of discarding blows, shorten the cleaning time, reduce the amount of thinner used, and reduce the cleaning cost.

The painting robot 11 is provided with a painting gun 18.
Since the pre-cleaning can be performed by the above-mentioned circulation processing while moving to the blowing position, the cleaning time is further shortened. FIG. 5 is a flowchart of a modified example of the control process executed by the CPU 36. In FIG. 5, S3
Steps 1 to S35 are the same as steps S11 to S15, and thus description thereof is omitted here.

In S36, the number m of washings is calculated from the characteristics of the paint (viscosity, temperature, specific gravity, metallic type, etc.). In the next step S37, the air operation valve 31h, which is an air valve of the color changing valve unit 23, is opened to supply air to the paint supply system 21, and paint remaining in the paint supply system 21 is thrown away. Subsequently, in S38, the air operation valve 31g, which is a thinner valve of the color changing valve unit 23, is opened to supply thinner to the paint supply system 21, and the paint remaining in the paint supply system 21 is thrown away. . Then, in S39, the number of discarded blows is checked. In this step S39, the number of times of discard blowing is S36.
If the number of times obtained in step m has not been reached, the above steps S37 and S38
Is repeated. However, the number of blows is m
If the number of circulations has been reached, the process proceeds to S40, and the number of circulations n is calculated from the characteristics (viscosity, temperature, specific gravity, metallic system, etc.) of the paint.

The next processing of S41 to S47 is the same as that of S
Steps S15 to S21 are the same, and a description thereof will be omitted.
In S41 to S47, the thinner moved in the forward rotation direction of the paint pump 25 for a predetermined time in the bypass system passage 22 and the paint supply system 21 formed between the upstream three-way valve 24 and the downstream three-way valve 27. Thereafter, the paint pump 25 moves in the reverse rotation direction. In this way, the thinner filled in the bypass system passage 22 and the paint supply system passage 21 reciprocates, whereby the insides of the paint pump 25 and the flow meter 26 having complicated internal structures are cleaned.

Then, in S48, the number of circulations is increased in S40.
It is checked whether or not the number of times n calculated in is reached.
In S48, if the number of circulations is n or less, the processes of S41 to S47 are repeated. However, when the number of circulations reaches n times, the processing after S49 is executed.
Note that the processing in S49 to S56 is performed in S23 to S30 described above.
Since the processing is the same as that described above, the description is omitted.

As described above, even if the circulation processing is performed after the throw-off processing is performed several times, the cleaning efficiency of the paint can be improved as in the above-described embodiment. As a result, the cleaning time can be reduced. In addition, S3
In steps 6 and S40, the number of washings m and the number of circulations n can be set according to the characteristics of the paint (viscosity, temperature, specific gravity, metallic type, etc.).
The cleaning process can be performed according to changes in the type of paint remaining in the paint and the environment, and the cleaning efficiency can be further improved.

FIG. 6 is a system diagram for explaining a modification of the present invention. As shown in FIG.
A discharge three-way valve 45 is provided between the upstream three-way valve 24 and the upstream three-way valve 24. The discharge three-way valve 45 has a bypass system 22 connected to the inflow port a, and a bypass system 4 connected to the branch port b.
6 is connected, and a thinner discharge path 47 is connected to the outflow port c.

Here, when performing the cleaning process, the paint supply line 21, the paint pump 25, the flow meter 26, and the bypass lines 22, 46 are filled with thinner, and then the paint pump 2
5 is a forward rotation operation and a reverse rotation operation to transfer the thinner to the paint supply system 2.
1 and the bypass systems 22 and 46. After this,
The discharge three-way valve 45 switches so that the inflow port a communicates with the outflow port c. As a result, the thinner circulating the thinner in the paint supply system 21 and the bypass systems 22 and 46 is discharged to the thinner discharge system 47.

For this reason, the thinner that has cleaned the inside of the paint supply line 21, the paint pump 25, and the flow meter 26 is discharged before the coating gun 18 moves to the discarding position. Therefore, the efficiency of the cleaning process can be improved. Also, when filling the thinner, the thinner is discharged to the thinner discharge system 47 via the discharge three-way valve 45 to increase the efficiency of filling the thinner so that the thinner can be discharged in a short time by the paint supply system 21 and the bypass system 22. Can be filled.

In the above embodiment, the color changing valve unit 23 is provided on the upper surface of the second arm 16 of the painting robot 11.
Although the configuration in which the coating equipment such as the paint pump 25 and the flow meter 26 is disposed has been described as an example, the configuration is not limited thereto. For example, the color changing valve unit 23, the paint pump 25, the flow meter 2
Of course, the present invention can also be applied to a configuration in which coating equipment such as 6 is disposed outside the base 13 of the coating robot 11 or in the vicinity of the coating robot 11.

[0039]

As described above, according to the first aspect of the present invention, one end is connected to the paint supply system upstream of the pump,
Since the other end is provided with a bypass system connected to the paint supply system downstream of the pump, the paint remaining in the paint supply system before the paint gun moves to the throw-off position during color change is supplied to the bypass system together with thinner supply. By circulating in a road, the inside of a coating device such as a pump, which is complicated and difficult to clean, can be cleaned. As a result, the cleaning time can be reduced, and the number of times of cleaning can be reduced, so that the amount of thinner used can be saved.

According to the second aspect of the present invention, when cleaning the paint supply line and the pump itself, the normal rotation operation and the reverse rotation operation are alternately performed so that the cleaning liquid circulates via the bypass line. Therefore, at least the paint remaining in the paint supply system and the pump can be efficiently washed, and the number of washings can be reduced, and the amount of thinner used can be reduced.

[Brief description of the drawings]

FIG. 1 is a side view showing the configuration of an embodiment of a painting robot according to the present invention.

FIG. 2 is a system diagram showing a configuration of a paint supply system.

FIG. 3 is a block diagram illustrating a configuration of a robot controller 20 and each device.

FIG. 4 is a flowchart of a control process executed by a CPU 36;

FIG. 5 is a flowchart of a modified example of the control process executed by the CPU 36;

FIG. 6 is a system diagram for explaining a modification of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 11 Painting robot 13 Base 14 Revolving base 15 1st arm 16 2nd arm 17 Wrist 18 Painting gun 20 Robot controller 21 Paint supply system 22 Bypass system 23 Color change valve unit 24 Upstream three-way valve 25 Paint pump 26 Flow meter 27 Downstream three-way valve 36 CPU 37 ROM 45 Three-way discharge valve 46 Bypass system 47 Thinner system

 ────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Yuji Fujinuma 1-3-6 Fujimi, Kawasaki-ku, Kawasaki-shi, Kanagawa Prefecture Tokiko Corporation F-term (reference) 3F060 AA06 BA00 CA21 DA10 EB13 EC13 FA01 FA03 HA00 HA03 4F033 AA01 BA03 GA00 GA01 PA11 4F035 AA03 BA05 BA12 BA15 BC02 BC06

Claims (2)

[Claims] 1. A coating robot configured to supply a paint to a coating gun mounted on a tip of an arm through a paint supply system, wherein a pump is provided in the paint supply system, and one end of the pump is provided by the pump. A coating robot, further comprising a bypass system connected to the paint supply system upstream and the other end connected to the paint supply system downstream of the pump. 2. The coating robot according to claim 1, wherein the pump circulates a cleaning liquid via the bypass system when performing cleaning processing on the paint supply system and the pump itself. A painting robot characterized by alternately performing a forward rotation operation and a reverse rotation operation.