JPH0760172A - Automatic coating device - Google Patents

Abstract

PURPOSE:To coat with high precision by adjusting coating width being affected by a temp. variation, a pressure variation, or the like, and changing, corresponding to its variation, to expand automation of the coating work and also to attain reduction in cost. CONSTITUTION:In an automation coating device having a driving means 2 mounted a spray means 3 by which a high viscous paint is sprayed under high pressure and applied, the device is provided with a temp. sensor 6 provided in the vicinity of the spray means 3, a pressure sensor 7 provided in the vicinity of the spray means 3, a position correcting arithmetic means 8 performing the position correction of the spray means 3 by a value detected by both sensors, and a control means 9 moving the spray means 3 based on a calculated value by the position correcting arithmetic means 8.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a device for mounting a spray means for spraying a highly viscous paint on a drive means and spraying the paint at a high pressure to apply the paint to the back and floor of a vehicle body. The present invention relates to an automatic coating device for controlling the.

[0002]

2. Description of the Related Art Conventionally, in a passenger car, a vinyl chloride resin sol-type paint (hereinafter referred to as PVC) is applied to the bottom surface of a vehicle body for the purpose of rust prevention, vibration prevention and sound insulation. In order for the PVC applied at this time to achieve effects such as rust prevention,
The coating thickness of PVC is required to be 500 μ or more. This is because if the PVC coating thickness is less than 500μ, the floor will transmit vibrations generated by the engine etc. to the entire vehicle body,
This is because there is a problem that rust may occur due to aging. On the other hand, if the thickness of PVC is 500 μ, there is no problem because the PVC function is effectively exhibited even when the thickness is more than 500 μm.

The following is a conventional apparatus for applying such a PVC to the floor and underside of a vehicle body. FIG. 3 is a schematic view showing a conventional automatic coating device. The robot 12, which is a driving unit having a plurality of joints in the shape of an arm, is supported by the fixed unit 11 in a drivable manner. An airless gun 13 (hereinafter, simply referred to as a gun) that sprays and applies PVC at high pressure is attached to the tip of the robot 12. And the fixed part 11 and the robot 1
The hose 2 is provided with a supply hose 14 and a discharge hose 15 so as to circulate the PVC through the gun 13.

With such a structure, PVC kept at a constant temperature in the tank is sent to the gun 13 via the supply hose 14 by a pump (not shown). Then, the PVC sent to the gun 13 is a nozzle 13 which is a spray port.
It is sprayed from a and applied to the floor bottom surface 16 of the vehicle body. On the other hand, the unsprayed PVC flows out of the gun 13 through the discharge hose 15, and the PVC is returned to the tank.
Here, FIG. 4 is a diagram showing the floor bottom surface of the vehicle body to which PVC is applied, FIG. 4 (A) is a diagram showing the entire floor back surface, and FIG. 4 (B) is a diagram of FIG. It is the figure which showed a part of application part of A cross section.

The coating apparatus coats the entire floor back surface 16 of the vehicle body with a thickness of 500 μm or more as shown in FIG. 4 while spraying PVC as described above. Also, FIG. 4 (B)
As shown in Fig. 1, one-time application width m to maintain the thickness of 500μ
Is about 200 mm, while the overlapping width n is set to 30 to 40 mm in the adjacent areas, and overlapping coating is performed in parallel. This is to prevent the coating width of PVC from fluctuating and producing an uncoated portion due to the influence of the temperature change of PVC as described below. As described above, when performing the coating operation, the robot 12 does not cover the PVC on a predetermined area on the bottom surface of the vehicle body.
Adjust the indirect part of the robot 12 to apply P
Guide the gun 13 so that VC is applied at regular intervals.

[0006]

However, the PVC sprayed from the gun 13 and sprayed on the vehicle body is a high-viscosity paint, and the viscosity changes greatly with temperature, and the spray pattern of the sprayed PVC is applied by the viscosity change. The width becomes uneven. That is, PV that is such a high-viscosity paint
The viscosity of C is, for example, 600 poise at a temperature of 20 degrees, whereas when the temperature changes by 10 degrees, the viscosity changes by 7 to 8% and a viscosity change of 42 to 48 poise occurs. If the viscosity changes due to temperature change, it affects the coating width of the PVC spray. Specifically, when the distance from the nozzle 13a to the floor back surface 16 of the vehicle body is 250 mm and it is attempted to spray the floor back surface with a width of 200 mm, when the temperature rises by 1 degree, that is, the viscosity changes by about 5 poise. It has been confirmed by an experiment that in the case of 7 mm, it widens, and on the contrary, when it lowers once, it narrows by 7 mm. In practice, when the coating of one vehicle is finished and the vehicle body is replaced, the coating device is stopped for 20 to 30 seconds.
This is a particular problem when the PVC cools and the temperature changes greatly, resulting in changes in the coating width.

On the other hand, regarding the relationship between the pressure and the coating width,
PVC spreads 0.6 mm when the pressure sent to the gun 13 rises by 1 kg / cm ^{2 and} 0.6 m when it falls by 1 kg / cm ^2.
The result is narrower. Therefore, the conventional automatic coating device is PVC, which is a highly viscous paint that is easily affected by temperature changes.
In order to stabilize the coating width by the spraying, the purpose was to stabilize the PVC material supply temperature.
For this reason, the fixed portion 11 of the robot is temperature-controlled by double pipes for hot and cold water, and the robot 12 is adjusted by heat retention by a heat retention hose.

However, the operation of the robot 12, which is the driving means, is restricted by the heat-insulating hose. That is, the supply and discharge hose 1 provided in the robot 12
If the durability of the heat-insulating hoses integrally provided so as to heat-insulate the heaters 4 and 15 is improved, the resistance against the operation of the drive means 12 is increased. Therefore, if the operation accuracy of the robot 12 is to be increased to some extent, the durability of the heat retaining hose is unavoidably reduced, resulting in insufficient heat retention. Therefore, the PVC in the supply hose 14 is affected by the atmosphere, the temperature of the paint at the nozzle 13a at the tip of the gun 13 changes, and the coating width of the sprayed PVC changes.
Then, this fluctuation causes the following inconvenience.

As described above, the gun 13 has a coating width of 200
PVC is sprayed so as to have an interval of mm, and an overlapping portion of 30 to 40 mm is provided so as to be adjacent to the application region. This is to prevent the uncoated portion from being generated due to the change in the coating width described above. As a result, the coating material is used more than necessary due to excessive PVC overcoating, which causes a cost increase. On the other hand, if the uncoated portion is generated by narrowing the overlapping coating width,
Defective products will occur.

FIG. 5 is a view showing a state in which PVC is applied to the back surface of the vehicle body by the above-mentioned application device. In particular, it is a diagram showing a state in which PVC has been applied beyond the predetermined region at the end of the floor bottom surface of the vehicle body. As described above, it is preferable that the PVC can be sprayed so as to maintain the thickness of 500 μ and remove the uncoated portion so that the PVC is contained in the end of the floor rear surface 16 of the vehicle body.
However, the coating width of the PVC spray may fluctuate under the influence of temperature and pressure, and the spray may exceed a predetermined area.

Therefore, when it occurs at the end of the floor bottom surface 16 of the vehicle body, the PVC wraps around the surface of the vehicle body to cause dust fog, as shown in FIG. Will result. Therefore, in order to prevent the quality failure due to dust fog on the vehicle body surface, the end portion 16a of the floor rear surface 16 of the vehicle body is provided with an uncoated portion of a predetermined width. Then, in the area where the PVC is not applied, manual work is performed in order to achieve effects such as rust prevention, vibration proofing, and soundproofing when applying the PVC. However, conventionally, there has been a problem that a considerable amount of uncoated portion has to be provided in consideration of a change in the coating width of PVC, which requires a lot of time and labor for manual work, resulting in poor production efficiency.

The present invention is an automatic method capable of improving the accuracy of the coating width by adjusting the spray width of the high-viscosity paint, which is affected by temperature changes, pressure changes, etc. and fluctuates in accordance with the changes. An object is to provide a coating device.

[0013]

An automatic coating device of the present invention comprises a spraying means for spraying a high-viscosity coating material onto a surface of an object at a high pressure, and a driving means capable of moving the spraying means three-dimensionally. In the automatic coating device having, the paint supply means for supplying the high-viscosity paint to the spraying means, the temperature sensor provided in the paint supply means, and the value detected by the temperature sensor provided in the paint supply means. Having the spraying means, and having distance correction means for correcting the distance to the surface of the object. Further, the automatic coating device of the present invention has a temperature sensor provided in the paint supply means or a pressure sensor provided in the paint supply means. Further, the automatic coating apparatus of the present invention has a temperature sensor provided in the paint supply means and a pressure sensor provided in the paint supply means.

[0014]

The automatic coating apparatus of the present invention having the above structure is
The fuel supply means supplies the high-viscosity paint to the spraying means,
With respect to the supplied fuel, the sensors provided in the paint supply means detect the pressure, the temperature, etc. near the PVC outlet. Then, the distance correction calculation means calculates the amount of movement of the spraying means that provides the predetermined coating width. After the calculation processing of the distance correction calculation means is completed, the control means controls the drive means based on the value so that the coating width becomes a predetermined coating width, and the drive means moves the spraying means three-dimensionally, Guide to a predetermined position. Then, the spraying means sprays the high-viscosity paint at high pressure.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing an embodiment of the automatic coating device of the present invention. The automatic coating apparatus of the present embodiment is provided so that a robot 2, which is an arm-shaped driving means having an indirect connection with a fixed portion 1, can be driven. At the tip of the robot 2, an airless gun (hereinafter,
3) is attached. The gun 3 is provided with a nozzle tip 3a for spraying PVC at the tip, and a supply hose 4 for supplying PVC to the gun 3 and a discharge hose 5 for discharging PVC from the gun 3. It is provided. A temperature sensor 6 and a pressure sensor 7 for detecting the temperature and pressure of PVC are attached to the supply hose 4 immediately before the gun 3.

Further, in the automatic coating apparatus of the present embodiment, the position correction calculation means 8 for performing calculation using the data detected by the temperature sensor 6 and the pressure sensor 7 is connected to the temperature sensor 6 and the pressure sensor 7. ing. The control means 9 for controlling the movement of the robot 2 based on the value output by the position correction calculation means 8 is connected to the position correction calculation means 8. Also, the control means 9
Is connected to the fixed part 1 having a control mechanism for controlling the drive of the robot 2.

With such a structure, the automatic coating apparatus of this embodiment operates as follows. First, the PVC kept at a predetermined temperature in the tank
It is sent to the gun 3 via the supply hose 4. A part of the PVC sent to the gun 3 is sprayed from the nozzle tip 3a and applied to the floor back surface 16 of the vehicle body. At this time, the robot 2 guides the gun 3 to apply the PVC to the floor bottom surface 16 of the vehicle body while keeping the overlapping width of 15 mm with the application width of 200 mm centering on the fixed portion 1. And the nozzle tip 3
The PVC not sprayed from a enters the discharge hose 5, is sent to the pump again, and is sent to the gun 3 via the supply hose 4. In this way, PVC flows so as to constantly circulate in a certain path. This is gun 3 with any amount of PVC
To supply to. Also, the fluid pressure at this time is 100
It is kg / cm ² .

The supply hose 4 and the discharge hose 5 attached along the arm of the robot 2 cannot be provided with a thick protective cover or the like in order to increase the degree of freedom of movement of the robot 2. Therefore, the temperature of the PVC changes, and the flow pressure of the circulating PVC changes. Therefore,
A temperature sensor 6 and a pressure sensor 7 attached to the supply hose 4 immediately before the gun 3 detect both the changing temperature and pressure immediately before the circulating PVC is injected toward the vehicle body. The temperature sensor 6 is detected at a level of 0.1 degree. Then, the position correction calculation device 8
However, based on the detected temperature and pressure data, the amount of change in the spray pattern width of the PVC is calculated based on the error from the respective predetermined values, and the gun position correction amount is obtained.

Specifically, the gun position correction amount X is X = (A−A ′) L / A ′ (1) A ′; estimated pattern width (mm) A; reference pattern width (mm) L; gun reference It is calculated by the distance (mm). Further, the estimated pattern width A 'is A' = C1T + C2P + C3 ... (2) T; obtained by a constant; the material temperature (in degrees) P; material pressure ^{(kg / cm 2) C1,} C2, C3. Here, the constants C1, C2, C3 are determined by conditions such as the shape of the nozzle tip 3a, and if the nozzle tip is changed, the constants are also changed accordingly. The standard condition when using the automatic coating device is P
The temperature and pressure of VC are T = 20 (degrees) and P = 100 (k
g / cm ² ), the gun reference distance L and the reference pattern width A are L = 250 (mm) and A = 200 (m, respectively).
m). Therefore, the constants C1, C2, C3 of the equation (2) satisfying the standard condition for a given nozzle tip are determined. And the temperature sensor 6 and the pressure sensor 7
Detects the temperature and pressure state of the PVC flowing through the supply hose 4, and the position correction calculation means 8 substitutes the value of the detected data into the equation (2) for calculation to determine the estimated pattern width A '.

Therefore, for example, the position correction arithmetic unit 8 sets the estimated pattern width A '= 250 mm due to temperature and pressure changes.
Finally, from the equation (1), X = (A−A ′) L / A ′ = (200−250) × 250/250 = −50 Then, the calculated data is The data is inputted to the robot control means 9, and the control means 9 drives the driving means 2 of the robot so as to move the gun 3 back and forth with respect to the vehicle body based on the data.

That is, if the estimated pattern width A'is 250 mm and the gun position correction amount X is -50, the reference pattern width is 200 mm, so overspray is 50 mm. Therefore, to correct this to the reference pattern width, as shown in FIG. 2, the robot 2 is driven to the front so as to bring the gun 3 closer to the vehicle body by X. That is, the gun position correction amount X drives the gun 3 closer to the vehicle body if the value is negative, and moves it away if the value is positive.

Therefore, in the automatic coating apparatus of the present embodiment, the temperature sensor 6 and the pressure sensor 7 for detecting the change of the PVC which is the high viscosity paint flowing through the supply hose 4 are detected by the automatic coating apparatus for spraying PVC by the gun. Since the position correction calculation means 8 for calculating the correction amount based on the paint data and the control means 9 for controlling the robot 2 based on the correction amount are used, even if the coating width changes due to the temperature change or the pressure change of the PVC, the desired value is obtained. It was possible to apply PVC with good dimensional accuracy to the area to be covered, and in the experiment, it was possible to suppress an error of 6.4 mm with respect to the reference pattern width of 200 mm. Therefore, it was possible to reduce costs by eliminating the use of extra paint with a minimum of repeated coating.

Although an example of the embodiment has been described above, the present invention is not limited to the above-described one, and various modifications can be made. For example, since the shape differs depending on the location of the vehicle body, the reference coating width may be changed and set according to the shape change, and spraying may be performed so as to obtain an appropriate coating width suitable for the shape. . Further, the approximate expression for the positioning performed by the distance correcting means is not limited to the above expression.

As is apparent from the above description,
In the automatic coating device of the present invention, the position correction calculation means calculates the position correction amount of the spraying means provided in the driving means from the value detected by the sensor provided in the fuel supply means for supplying the vinyl chloride sol of the robot, and the position thereof is calculated. Since the control means moves the spraying means by the correction amount calculated by the correction calculating means,
Since the coating width, which fluctuates due to the influence of temperature change, pressure change, etc. on the PVC, can be adjusted according to the change, highly accurate coating is possible.

[Brief description of drawings]

FIG. 1 is a diagram showing an automatic coating device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a driving position of a gun of the automatic coating apparatus according to the embodiment of the present invention.

FIG. 3 is a diagram showing a conventional example of an automatic coating device.

FIG. 4 is a diagram showing a state in which paint is sprayed on the back surface of the vehicle body floor.

FIG. 5 is a diagram showing a state of spraying paint onto a vehicle end portion performed by a conventional automatic coating device.

[Explanation of symbols]

 1 Fixed Part 2 Drive Means 3 Airless Gun 3a Nozzle 4 Supply Hose 5 Discharge Hose 6 Temperature Sensor 7 Pressure Sensor 8 Position Correction Calculator 9 Control Means

Claims (3)

[Claims] 1. An automatic coating device comprising a spraying means for spraying a high-viscosity coating material onto a surface of an object by high-pressure spraying, and a drive means capable of moving the spraying means three-dimensionally. A paint supply means for supplying a high-viscosity paint, a temperature sensor provided in the paint supply means, and a distance correction means for correcting the distance between the spraying means and the object surface based on the value detected by the temperature sensor. An automatic coating device having. 2. An automatic coating device having a spraying means for spraying a high-viscosity coating material onto a surface of an object at a high pressure and applying the spraying means in a three-dimensional manner. A paint supply means for supplying a high-viscosity paint, a pressure sensor provided in the paint supply means, and a distance correction means for correcting the distance between the spraying means and the surface of the object by the value detected by the pressure sensor. An automatic coating device having. 3. An automatic coating device comprising a spraying means for spraying a high-viscosity coating material onto a surface of an object at high pressure and applying the spraying means, and a driving means capable of moving the spraying means three-dimensionally. Paint supply means for supplying high-viscosity paint, temperature sensor and pressure sensor provided in the paint supply means, and the distance between the spraying means and the object surface is corrected by the values detected by the temperature sensor and pressure sensor. An automatic coating device, comprising: