JPH0338906B2 - - Google Patents

Description

Detailed Description of the Invention (Industrial Field of Application) The present invention relates to the application of sealant in automatic sealant application in which a sealant is applied to the necessary parts of an automobile body on a conveyance line by a sealant application robot. This concerns the supply method.

(Prior art) Sealing to provide airtightness and liquidtightness to the joints of panels, etc. that are joined to spots on the car body by welding, etc. is done manually using a sealing gun on the conveyor line. It is being carried out. There are a wide variety of locations that require such sealing, especially in the innermost parts of the engine room, where work is forced to be done in an awkward position and work must be done quickly, resulting in a large number of problems due to the limitations of manual work. Due to this problem, the current situation is that many people are involved in the sealing process.

(Problems to be Solved by the Invention) In view of the above-mentioned conventional problems, a sealing robot equipped with a sealing gun is placed on a conveyance line in order to automate the sealing work, and the sealing robot performs sealing according to the steps of the work program. Methods of having the work done have also been tried, but
There are problems that need to be improved, such as the nozzle misaligning from the panel seam of the area to be coated due to variations in the panel seam and errors in body accuracy, making it impossible to achieve good sealing. to eliminate variations in seams, etc.
Improving the accuracy of automatic sealing work using sealing robots is being researched.

By the way, in the above-mentioned sealing work performed by a robot, it is necessary to supply the sealant with a metered supply pump, and if an abnormality such as a blockage occurs on the discharge side of the pump when such a robot is supplying the sealant and applying the sealant, there is no abnormality in the piping. There is a risk that the pressure will become high and destroy piping equipment, etc.If a material supply abnormality occurs on the pump suction side, the pump will run dry,
There is a risk of damage, and if left under pressure for a long time, the sealant will solidify, so measures must be taken to release the residual pressure after the work is completed.

The present invention has been made to solve the above problems, and its purpose is to automatically apply sealant by a sealing robot, and if an abnormality occurs on the sealant supply line, This is detected and the abnormality is dealt with in order to protect the sealant supply system.

(Means for Solving the Problems) A means for solving the above problems is a sealing method in which a sealant is applied to the necessary parts of an automobile body on a conveyance line by a sealing robot. A pressure sensor for high pressure is installed downstream of the sealant metering supply pump installed in the sealant supply system, and a pressure sensor for high and low pressure is installed upstream. A bypass system is provided upstream of the high and low pressure pressure sensors in the supply system, and each system is provided with a relief valve that opens when abnormal pressure is detected by each of the sensors, and the relief valve is connected to the pressure relief bypass system. , and the operation of the metering pump is configured to be stopped when abnormal pressure is detected by the sensor.

(Effects of the above means) According to the above means, the relief valve is opened in the event of pressure abnormality to release the pressure in the sealant supply system, while the operation of the pump is stopped, and the piping, equipment, and pump are protected.

(Example) Next, an example of the present invention will be described in detail with reference to the accompanying drawings.

Fig. 1 is an explanatory diagram of a sealing robot and a sealant supply system. 1 is a robot, and a sealant application nozzle 2 is provided at the tip of the robot, a coating gun 3 is attached to this, and opening and closing of the gun 3 closes the nozzle. The sealant from 2 is supplied and shut off.

The supply system includes a sealant storage tank 4 and a main pump 5 for pumping up the sealant, and the sealant is sent from the pump 5 through a main line 6 and then to a branched supply line 7 for each robot. The line 7 has a switching valve 8 and a line stop valve 9 downstream thereof.
A filter 10 is provided downstream of the valve 9, and a regulator 11 is provided downstream of the filter 10.
A pump 12 for quantitatively supplying sealant is installed downstream of the regulator 11, and the pump 12 is driven by a motor 13,
It is operated via a reduction gear 14.

A high pressure sensor 15 is installed downstream of the pump 12 in the line 7 to detect pressure above a predetermined level in the line, and a high/low pressure sensor 15 is installed upstream to detect pressure above and below a predetermined level in the line. A sensor 16 is provided. Piping 17 is downstream of the high pressure sensor 15.
It is connected to the gun 3 of the robot 1 through the nozzle 2 to supply sealant to the nozzle 2, and a relief bypass path 18 is branched to the line downstream of the piping 17 and downstream of the sensor 15. A relief valve 19 is provided, the relief valve 19 is closed by an actuator 20, and the valve 19 is normally closed. Valve 19
A check valve 21 is provided downstream of the tank 4, and a reflux line 23 is connected to the tank 4 via a switching valve 22.
Connect to. In addition, a relief bypass line 24 is branched between the regulator 11 of the line 7 and the high/low pressure sensor 16, and a relief valve 25 that is opened and closed by an actuator 26 is interposed in this line 24. 25 is normally closed, and a check valve 27 is interposed downstream of the valve 25, and the check valve 21
It merges with the downstream and connects to the system line 23.

The actuators 20, 26 of the relief valves 19, 25 and the actuator 28 of the stop valve 9 described above are operated by a pneumatic system 2, for example, which opens and closes them.
In the figure, the solenoid valve 31 for opening and closing the gun 3 described above is also installed in the circuit, and each of the valves 30 and 31 is connected to a pressure source 32, and the solenoid valve 30 is connected to the The A position where the actuators 20, 26, and 28 are connected is the closed position of the actuators 20, 26, 28, and the B
The position is assumed to be the open position of the actuators 20, 26, and 28.

In the above, the sealing agent in the tank 4 is sent to the pump 12 via the filter 10 and the regulator 11 via the lines 6 and 7, is pressurized by the pump 12, and is sent from the nozzle 2 via the gun 3 of the robot 1 via the piping 17. It is discharged and a sealant is applied.

By the way, if the pressure sensors 15 and 16 indicate that the pressure of the sealant in the line is abnormal, the process will be as follows, and FIG. 2 is a block diagram illustrating this.

When the pressure downstream of the pump 12 is high, for example when the nozzle is clogged and the pressure exceeds a predetermined value, the pressure is compared in the comparison circuit 33, and if it is high, the detection signal is sent to the drive circuit of the motor 13 of the pump 12. 3
4 and turns it off, stopping the operation of the pump 12. On the other hand, at the same time, the signal is transmitted to the relief valve 19.
to the drive circuit 35 of the solenoid valve 30 for driving the actuator 20 and switch it from the A position to the B position in the figure, that is, the actuator 20 is opened, the relief valve 19 is opened, the pressure in the line 7 is released, and at the same time The operation of the pump 12 is stopped.

When the pressure upstream of the high/low pressure sensor 16 is high, an output is similarly obtained via the comparison circuit 36, the motor drive circuit 34 is turned off, and the operation of the pump 12 is stopped, while the actuator 26 of the relief valve 25
The output is also sent to the drive circuit 37 of the driving solenoid valve 30, the valve 30 is switched from the A position to the B position in the same way as above, the actuator 26 is opened, the relief valve 25 is opened to release pressure, and at the same time the pump Stop the operation of 12.

If the pressure upstream of the pressure sensor 16 is below a predetermined value, it is compared and detected via the comparison circuit 36, the motor drive circuit 34 is turned off, the pump 12 is prevented from running dry, and the relief valve 25 is also opened. .

When the operation of the other lines mentioned above is stopped, the solenoid valve 30 is normally closed A by turning off the power switch.
The excitation to the position is stopped, the valve 30 is returned to the B position, and the relief valves 19 and 25 are opened to release the pressure in the line and prevent the sealant from solidifying.

As described above, a pressure abnormality is detected, the operation of the pump is stopped, and the relief valve is opened to release the pressure in the line.

(Effects of the Invention) As is clear from the above, according to the present invention, during sealing work by a sealing robot, when the sealing agent is supplied by the quantitative supply pump in the sealant supply circuit, clogging, material shortage, etc. By detecting abnormalities in high or low pressure, the relief valve is opened to reduce the line pressure, and the pump operation is also stopped. This protects the supply line and pump, and reduces the line pressure after work. The sealant can be prevented from solidifying, and can be realized with a simple configuration that includes a bypass circuit, a relief valve, a sensor, and a relief valve driving means.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention, and FIG. 1 is an explanatory diagram of a sealing robot and sealant supply system, and FIG. 2 is an explanatory diagram of a block. In the drawing, 1 is a sealing robot, 7 is a supply system, 12 is a pump, 15, 16 are sensors, 19,
25 is a relief valve, and 18 and 24 are relief bypass lines.

Claims (1)

[Claims] 1. In a sealing method in which a sealant is applied to the necessary parts of an automobile body by a sealing robot on a conveyance line, a high-pressure A pressure sensor for high and low pressures is provided on the upstream side, and a bypass line is provided downstream of the high-pressure pressure sensor in the supply system and upstream of the high- and low-pressure pressure sensor in the supply system. Each system is provided with a relief valve that opens when abnormal pressure is detected by each of the sensors, the relief valve is connected to a bypass system for pressure relief, and the operation of the quantitative supply pump is stopped when abnormal pressure is detected by the sensor. A method for supplying sealant in a sealing robot, characterized in that: