JPH0515817A - Coating method and device thereof - Google Patents

Abstract

PURPOSE:To obtain the coating method and device which efficiently execute coating along a surface to be coated with one coating gun by providing a coating machine body movably forward and backward along the transporting direction of a material to be coated, dividing the total coating region to plural coating blocks in the forward and backward moving directions of the coating gun and variably controlling the forward and backward moving loci of the coating gun. CONSTITUTION:The entire coating region is divided to the plural coating blocks H1, HU, H2 in the forward and backward moving directions of the coating gun 7 and the coating is successively executed, by which the entire part of the coating region can be coated without allowing the coating gun 7 to make useless movements. The forward and backward moving loci of the coating gun 7 are variably controlled according to the respective coating blocks H1, HU, H2, by which the forward and backward moving stroke and gun speed of the coating gun 7 are maintained constant and the variable control of the curved surface shape of the forward and backward moving loci of the coating gun 7 is executed according to the curved surface shape of the surface to be coated. Then, the thickness of the coating film over the entire part of the coating region of the material B to be coated is uniformly maintained and the coating along the surface to be coated is efficiently executed.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention, when coating an object to be coated, which is being conveyed, applies a coating gun to the object to be reciprocated in a predetermined direction or while moving along the shape of the portion to be coated. And a device therefor.

[0002]

2. Description of the Related Art Conventionally, when coating an article to be coated that is being conveyed, the coating gun is moved along the predetermined locus and reciprocates, for example, in a direction orthogonal to the conveying direction. The coating method of coating while performing is generally well known. For example, in a car body painting line or the like, when painting a side portion of a vehicle body that has been brought into a painting station, a painting gun is applied while reciprocating vertically with respect to the side surface of the vehicle body to be painted. The painting method is commonly used.

As such a coating method and its apparatus, for example, in Japanese Unexamined Patent Publication No. 1-297168, the side coating surface of the vehicle body is divided into a plurality of parts in the height direction and the coating guns are arranged at different height positions. Then, by reciprocating each coating gun up and down by a predetermined amount to coat the side parts of the vehicle body, the substantial amount of displacement of each coating gun is greatly reduced, and the speed of the vehicle body transportation line and coating are increased. It is disclosed that the work efficiency is improved. However, in the above-mentioned conventional example, since a plurality of coating guns are provided and the displacement and spraying operation of the paint are individually controlled, the apparatus is large-scaled and the structure thereof is complicated, and a large installation space is required and the equipment cost is reduced. There is a problem of overcrowding.

On the other hand, various devices have been devised in which the side portion of the vehicle body is coated with one coating gun without using such a large-scale device.
In the 1970 publication, a guide rail that follows the curved shape of the vehicle body side guides the vertical movement of the coating gun, and
By providing a tilt mechanism on the support part of the coating gun,
It is disclosed that a vehicle body side portion formed in a curved shape can be coated while maintaining a constant coating distance and a constant coating spray angle.

By the way, when the paint is sprayed and applied to the surface of the object to be coated by a spray gun, the coating film thickness obtained by one spray coating is formed on the surface of the object to be coated as shown in FIG. 4, for example. It is known that the coating pattern is not constant in the width direction, but is thicker at the center of the pattern and thinner as it approaches both ends.

Therefore, in order to make the coating film thickness as uniform as possible and obtain good coating quality, the interval (pass pitch P) between each pass when the coating gun is reciprocated is set to the coating pattern width Wp.
However, it is necessary to regulate it to a certain value or less and to paint while wrapping the coating patterns of each pass. That is, it is necessary to secure a certain number of coatings or more for the surface portion of the object to be coated, and to keep the number of coatings constant over the entire coating surface. For this,
The stroke length and the gun speed during the reciprocating movement of the coating gun may be set to be constant.

[0007]

By the way, when the body of an ordinary automobile is viewed from the side, the front portion of the vehicle body (front fender portion), the center portion of the vehicle body (cabin side surface portion), and the rear portion of the vehicle body (rear fender portion) are separated. , Vertical lengths are quite different. When painting a vehicle body with such a side shape with a single gun, conventionally, the reciprocating stroke of the painting gun is adjusted to the side surface portion of the passenger compartment that has the longest vertical length, and the front and rear fender portions are partially Either stop spraying the paint and perform only the stroke operation, or perform partial coating by adjusting the reciprocating stroke of the coating gun to one of the front and rear fenders. By painting separately, the reciprocating stroke of the painting gun was kept constant.

However, in the above-mentioned conventional method, in the former case, the coating gun is caused to perform a stroke operation even in a portion which does not require the spraying of the coating material, so that the work efficiency of the coating process is lowered by this useless operation, Further, in the latter case, since the coating of the portion outside the above-mentioned coating range is a separate process, there is a problem that it is also disadvantageous in terms of improving productivity.

In addition, the upper half and the lower half of the vehicle body of an automobile usually have a slightly different curved surface shape on the side portion of the vehicle body. However, when a vehicle body having such a side shape is coated with one gun, Conventionally, the coating gun is generally reciprocated along an arcuate locus having a constant curvature from the upper half portion to the lower half portion. However, in such a method, the upper half and the lower half of the vehicle body cannot be separately painted according to the curved surface shape of the painted surface, which makes it difficult to coat the painted surface uniformly and efficiently. there were.

Further, when considering the vehicle body side part divided into an upper half part and a lower half part, the pillar part is considerably larger than the panel part in the upper half part. There is a problem in that efficient coating cannot be performed by simply reciprocating the coating gun in the vertical direction to coat such a coating area.

The present invention has been made in order to solve the above-mentioned problems, and when coating a transported object to be coated while operating the coating gun in accordance with a predetermined locus, one coating gun is used for coating. An object of the present invention is to provide a coating method and an apparatus therefor capable of efficiently performing coating along a coated surface.

[0012]

Therefore, the first invention of the present application is a coating method in which a coating gun is applied to an object to be coated conveyed while operating the coating gun in accordance with a predetermined locus. The coating gun is provided so as to be movable back and forth along the conveying direction of the article to be coated, and the coating gun is attached to the main body of the coating machine so as to be capable of reciprocating in a predetermined direction, and the entire coating area of the article to be coated is at least the coating gun. The coating block is divided into a plurality of coating blocks in the reciprocating direction, and the coating blocks are sequentially coated while the reciprocating trajectory of the coating gun is variably controlled according to each coating block.

A second invention of the present application is the same as the first invention, wherein when one of the coating blocks is completely coated, the coating gun is moved in a direction opposite to a coating direction, It is designed to start painting the next painting block.

Further, a third invention of the present application is the same as the first invention, wherein the coating area of the article to be coated is divided in the conveying direction of the article to be coated.

Furthermore, a fourth invention of the present application is a coating apparatus for coating a conveyed object to be coated while operating a coating gun in accordance with a predetermined locus, in the conveying direction of the object to be coated. And a reciprocating movement of at least the entire coating area of the object to be coated. Variable control means for variably controlling the reciprocating locus of the coating gun according to each of a plurality of coating blocks obtained by dividing the direction, and movement control means for sequentially moving the coating gun to each coating block. It is a thing.

Further, a fifth invention of the present application is a coating method for coating a conveyed coating object while operating a coating gun in accordance with a predetermined locus, wherein the coating machine main body is coated with the coating object. The coating gun is provided so as to be movable back and forth along the conveying direction, and the coating gun is attached to the coating machine main body so as to be reciprocable in a predetermined direction and movable along the shape of the coating portion of the coating object. The whole coating area is divided into a plurality of coating blocks at least in the reciprocating direction of the coating gun, and the coating blocks are sequentially coated while the operation of the coating gun is variably controlled according to each coating block. Is.

Further, a sixth invention of the present application is a coating apparatus for coating a conveyed coating object while operating a coating gun in accordance with a predetermined locus, in the conveying direction of the coating object. A coating machine main body provided so as to be able to move back and forth, a coating gun mounted so as to be capable of reciprocating in a predetermined direction with respect to the coating machine main body and movable along the shape of the coating portion of the coating object, Variable control means for variably controlling the operation of the coating gun in accordance with each of a plurality of coating blocks obtained by dividing the entire coating area of the object to be coated at least in the reciprocating direction of the coating gun, and the coating gun. And a movement control means for sequentially moving the coating block.

[0018]

According to the first invention of the present application, the entire coating area of the object to be coated is divided into a plurality of coating blocks at least in the reciprocating direction of the coating gun, and each coating block is sequentially coated. The entire coating area of the object to be coated can be coated without causing unnecessary movement of the coating gun. Moreover, since the reciprocating trajectory of the coating gun is variably controlled according to each coating block, the reciprocating stroke and gun speed of the coating gun can be controlled even when the curved surface shape of the surface to be coated is not constant over the entire coating area. It is possible to variably control the curved shape of the reciprocating locus of the coating gun according to the curved surface shape of the coated surface in each coating block while maintaining the constant. As a result, with one coating gun, the coating film thickness can be kept uniform over the entire coating area of the object to be coated, and coating along the surface to be coated can be efficiently performed.

According to a second invention of the present application, in the first invention, when one of the coating blocks has been painted, the painting gun is moved in a direction opposite to the painting direction. After that, the painting of the next painting block was started, so when moving the painting gun from the painting block that has finished painting to the next painting block, it is carried at a relative speed with respect to the object to be coated. By performing an advancing / retreating operation along the direction, that is, a so-called tracking operation, the length of the coating apparatus in the direction in which the coating object is conveyed can be shortened. As a result, it is possible to obtain the same effect as that of the first aspect of the invention, and it is possible to make the apparatus compact.

Further, according to the third invention of the present application, in the first invention, the coating area of the object to be coated is divided also in the transportation direction, so that the transportation of each coating block is performed. The directional length can be set to be short, and the tracking amount when sequentially moving the coating gun to each coating block can be reduced. As a result, the same effect as that of the first aspect of the invention can be obtained, and the length of the coating device in the conveyance direction of the object to be coated can be further shortened, so that the device can be made more compact. .

Further, according to the coating apparatus according to the fourth aspect of the present invention, since the variable control means and the movement control means are provided, the reciprocating locus of the coating gun can be determined according to the plurality of coating blocks. The coating blocks can be variably controlled and the coating blocks can be sequentially coated. That is, even if the curved surface shape of the surface to be coated is not constant over the entire coating area, the coating gun can be adjusted according to the curved surface shape of the surface to be coated in each coating block while keeping the reciprocating stroke and gun speed of the coating gun constant. It is possible to variably control the curvature of the reciprocating locus of, and one coating gun can be used to keep the coating thickness uniform over the entire coating area of the object to be coated, and to coat along the surface to be coated. You can do it efficiently.

Further, according to the fifth invention of the present application,
The entire coating area of the object to be coated is divided into a plurality of coating blocks at least in the reciprocating direction of the coating gun, and each coating block is sequentially coated so that the coating gun does not move uselessly. The entire painted area can be painted. Moreover, the coating gun is provided so as to be capable of reciprocating in a predetermined direction and movable along the shape of the coating portion of the object to be coated, and the operation of the coating gun is variably controlled according to each coating block. For parts where the shape of the painted part of the paint is not suitable for painting due to the reciprocating motion of the painting gun, the painting gun can be moved along that shape, and one painting gun can be used to paint along the coated surface. It can be performed more efficiently.

Further, according to the coating apparatus of the sixth aspect of the present invention, the coating gun is provided so as to be reciprocable in a predetermined direction and movable along the shape of the coating portion of the object to be coated, and the variable control is performed. Since the means and the movement control means are provided,
The operation of the coating gun can be variably controlled according to the plurality of coating blocks, and the coating blocks can be sequentially coated. That is, if the shape of the coating part of the object to be coated is not suitable for coating due to the reciprocating motion of the coating gun, the coating gun can be moved along that shape, and one coating gun It will be possible to perform more efficient painting.

[0024]

Embodiments of the present invention will now be described in detail with reference to the accompanying drawings in the case where the present invention is applied to, for example, coating on the side of a vehicle body. FIG. 1, FIG. 2 and FIG. 3 are a plan view, a front view and a side view schematically showing the configuration of a coating apparatus for carrying out the coating method according to the present invention. The coating apparatus 1 according to the present embodiment is laid on a base 2 and has two parallel traveling rails 3 extending along a vehicle body transport line Lb, and rectangular pillars arranged on the traveling rails 3, 3. Coating machine main body 4 and the coating machine main body 4
The arm support unit 5 supported by the arm support unit 5 in a direction orthogonal to the vehicle body transport line Lb in the horizontal plane (hereinafter, this direction is referred to as the front-back direction), and the vehicle body transport line Lb attached to the arm support unit 5. A coating arm 6 extending to the side and a coating gun 7 attached to the tip of the coating arm 6 are provided.

A traveling shaft Sx composed of a ball screw is extended between the two traveling rails 3 and 3 in parallel with both rails 3. One end of the traveling shaft Sx is an electric motor Mx (traveling shaft motor). ) Is connected to the output side. In addition, a box-shaped mounting unit 4u combined with the traveling shaft Sx is fixed to the bottom of the coating machine main body 4, and the traveling shaft Sx is rotatably driven by the traveling shaft motor Mx. However, it is made to travel via the mounting unit 4u. The traveling direction can be changed to the opposite direction by changing the rotation direction of the traveling shaft Sx. That is, the coating machine main body 4 can be moved back and forth in the carrying direction along the vehicle body carrying line Lb while being guided by the running rails 3 and 3 by driving the running shaft motor Mx.

A vertical elevating shaft Sz composed of a ball screw is arranged on the side surface of the coating machine body 4, and the lower end of the elevating shaft Sz is fixed to the lower portion of the coating machine body 4. Is connected to the output side of the electric motor Mz (elevating shaft motor). The arm support unit 5 is attached in a front-rear direction orthogonal to the elevating shaft Sz through the attaching unit 5u, and is rotated along the elevating shaft Sz by rotating the elevating shaft Sz by the elevating shaft motor Mz. It can reciprocate vertically.

Further, inside the main body 4 of the coating machine, a balance weight 14 is provided between the upper and lower sprockets 13a and 13b in order to assist the lifting and lowering operation of the arm supporting unit 5.
The lifting / lowering chain 12 to which is attached is installed, and the back side of the arm support unit 5 is fixed to an appropriate position of the chain 12.

On the side surface of the arm support unit 5,
An anteroposterior shaft Sy, which is formed of a ball screw and extends in the anteroposterior direction in a horizontal plane, is provided, and a rear end portion of the anteroposterior shaft Sy is an electric motor My (a longitudinal shaft motor) fixed to a rear end of the arm support unit 5. Are linked to. The coating arm 6 is attached in the same direction as the arm supporting unit 5, and is rotated in the horizontal direction along the front-rear axis Sy by rotationally driving the front-rear axis Sy by the front-rear axis motor My. The front and rear positions thereof are adjusted.

A coating gun 7 is attached to the tip end of the coating arm 6 through a tilt mechanism 8, and the coating is performed by driving an electric motor Mθ (tilt motor) attached to the tilt mechanism 8. The gun 7 can be tilted vertically in a vertical plane so that the tip of the gun 7 can be directed in a predetermined tilt direction. In addition, the painting gun,
In order to be able to point in various directions, with respect to the painting arm,
By being attached so as to be rotatable around the longitudinal axis of the front-rear axis Sy, the coating gun is not only tilted in the vertical direction but also is so-called robot-moved, and along the shape of the coating portion of the object to be coated. It can be moved.

The ball screw mechanism for moving the coating machine body 4, the coating arm 6, and the arm support unit 5 in the respective axial directions by rotationally driving the shafts Sx, Sy and Sz as ball screws, and the electric motor Mθ. The tilting mechanism 8 for tilting the coating gun 7 by driving is the same as that well known in the related art, and therefore the illustration and detailed description of the internal structure thereof are omitted.

Although not specifically shown in the drawing, the coating device 1 is provided with a control controller mainly composed of, for example, a microcomputer, while the electric motors Mx, My, Mz and Mθ are provided. Are each composed of, for example, an AC servo motor, and are connected to the controller so that signals can be exchanged. Then, according to the control signal from the controller, each of the servo motors Mx,
The drive / stop of My, Mz and Mθ, or the rotation speed and its direction are controlled appropriately.

In the above structure, when the vehicle body B is brought into the coating station, the operation of the coating apparatus 1 is started and the servomotors Mx, My, Mz and Mθ are driven. Then, while the vehicle body B is moved in the transport direction at a predetermined conveyor speed, the arm support unit 5 is reciprocated in the vertical direction on the side of the coating apparatus 1 and the front and rear of the coating arm 6 are moved in accordance with the vertical position. The position and the tilt angle of the coating gun 7 are controlled so as to correspond to the curved shape of the side surface of the vehicle body B. At the same time, the main body 4 of the coating machine
It can be moved back and forth in the vehicle body transport direction. That is, the so-called tracking operation is performed with respect to the conveyor speed of the vehicle body transport line Lb at a certain relative speed along the vehicle body transport direction.

In this embodiment, as shown in FIG. 5, the side surface of the vehicle body B to be coated is divided into an upper half portion HU and a lower half portion HL, and this lower half portion HL is referred to as a front portion H ₁ . Each of the coating blocks H ₁ and H obtained by dividing into the rear part H ₂ and dividing in this way
The coating is done sequentially for each U and H ₂ . That is,
First, after painting the coating block H ₁ on the lower half of the vehicle body, the coating machine body 4 is tracked to move the coating gun 7 to the coating block HU on the upper half of the vehicle body, and this block HU is coated. The coating machine body 4 is tracked to move the coating gun 7 to the coating block H ₂ in the lower rear part of the vehicle body, and finally the coating of the block H ₂ is performed.

The entire coating area on the side surface of the vehicle body is divided into the three coating blocks HU, H ₁ and H ₂ as described above, and the coating blocks H ₁ , HU and H ₂ are sequentially coated. With one coating gun 7, the coating film thickness can be kept uniform over the entire side of the vehicle body B to be coated, and the coating along the coated surface in each coating block H ₁ , HU, H ₂ can be performed efficiently. You can do it well.

That is, by dividing the side surface of the vehicle body B to be coated in the vertical direction which is the reciprocating direction of the coating gun 7, the upper half portion HU and the lower half portion HL of the vehicle body B are attached to the side panel of the side panel. It can be painted separately according to the curved surface shape. In this case, since the coating gun 7 does not reciprocate up and down in the uncoated portions before and after the coating block HU in the upper half of the vehicle body, the coating gun does not make unnecessary movements as in the conventional case. The entire painting area on the side surface of B can be painted, and the efficiency of the painting work is improved. Also,
By dividing the coating area into front and rear, the tracking amount when sequentially coating the divided coating blocks H ₁ , HU, H ₂ can be reduced, and the coating device 1 can be made more compact. .

The coating conditions of the coating blocks H ₁ , HU, H ₂ will be described below with reference to specific examples. First, with respect to the upper half portion HU and the lower half portion HL of the vehicle body, the trajectory when the coating gun 7 reciprocates up and down and the reciprocating stroke are calculated. In this example, the curves forming the outer shapes of the side surfaces of the upper half HU and the lower half HL of the vehicle body are approximated by, for example, an arc C having the same radius of curvature R with different center positions (see FIG. 6). .

Then, by appropriately setting the distance from the tip of the coating gun 7 to the surface of the vehicle body B (that is, the coating distance Dg) according to the coating conditions, the coating of the upper half portion HU and the lower half portion HL of the vehicle body is performed. The trajectory G of the vertical reciprocating motion of the coating gun 7 along the surface can be obtained respectively. The locus G is a composite combination of the up-and-down movement of the arm support unit 5 in the coating apparatus 1, the back-and-forth movement of the coating arm 6, and the vertical tilt operation of the coating gun 7. In the vehicle according to this specific example, the radius of curvature R of the locus G of the coating gun 7 is 1
The arc length L was 500 mm, and the arc length L when the coating gun 7 reciprocates up and down along the locus G was 800 mm in both the upper half HU and the lower half HL.

The coating gun 7 is applied to the body B continuously conveyed.
When coating while reciprocating, in order to keep the coating thickness sufficiently uniform, each coating pattern in one pass is wrapped by a predetermined amount with respect to the pattern width Wp (see FIG. 4). There is a need. In the present embodiment, this wrap amount is set to 1/2 of the coating pattern width Wp. Therefore, the movement amount per pass when the coating gun 7 is reciprocated, that is, the pass pitch P is ¼ of the coating pattern width Wp. Set to. In the specific example, the coating pattern width Wp is 300 mm. Therefore, the pass pitch P is set to 75 mm.

Further, the discharge amount Q of the coating material, the relative speed Vr in the conveying direction between the object to be coated and the coating gun, and the coating film thickness t have the relationship expressed by the following equation (1). By controlling a pump device (not shown) to adjust the discharge amount Q of the paint, or by controlling the rotation speed and the rotation direction of the traveling shaft motor Mx to adjust the relative speed Vr, a predetermined coating film thickness t can be obtained.
Can be obtained. In this embodiment, in order to prevent a change in the atomization state of the paint and obtain a stable coating quality, the formula (1)
In the above, the discharge amount Q of the paint was made constant.

Q = Vr · Lg · t · ρ ₁ · [(R−Dg) / R] / (ρ ₂ · NV · η) (1) In the above formula (1), each symbol is the following amount or Represents a constant. Lg: Stroke length of coating gun ρ ₁ : Film specific gravity of coating film (constant determined by physical properties of paint) ρ ₂ : Liquid specific gravity of coating material (constant determined by physical properties of paint) η: Efficiency (constant determined by coating equipment) R : Curvature of reciprocating motion of coating gun (constant determined by body shape) Dg: Coating distance (constant determined by coating conditions)

The stroke length Lg of the above coating gun
Is the length L of the trajectory G (arc-shaped curve) along which the coating gun 7 reciprocates in the vertical direction, and the length required for acceleration / deceleration at the time of folding back at the upper and lower ends when the coating gun 7 reciprocates. It is added, and can be calculated by the following equation (2).

[0042] Lg = L + Ta / Vg = Tp · Vg (2) In the above formula (2), each symbol represents the following amount. Vg: Tip speed of the coating gun during stroke operation Ta: Time required for acceleration / deceleration when folded back at the upper and lower ends Tp: Time required for one pass

In this example, the tip speed V of the coating gun is
g was set to 60 m / min as the highest level speed within the range in which the coating efficiency of a predetermined value or more could be reliably obtained, and the acceleration / deceleration time Ta was set to 0.3 seconds. Therefore, the required time Tp (= L / Vg + Ta) per pass is 1.1 seconds.

Since the relative velocity Vr, the pass pitch P, and the required time Tp per pass have the relationship shown in the following equation (3), the relative velocity Vr can be calculated from this equation (3). it can. P / Vr = L / Vg + Ta = Tp (3) In this example, the relative speed Vr is 4.09 m / min.
In the vehicle according to this example, the length L in the transport direction is 2.4 m for the upper half HU of the vehicle body, and 2.4 m for the lower half HL.
Has a length La of 5.1 m, and the coating time required for one vehicle was calculated from these values and the relative speed Vr to be 1.83 minutes.

Further, the discharge amount Q of the paint can be calculated by the following equation (4). Q = Vr.Lg.A = Tp.Vg.A (4) In the above equation, A is a constant term. In this specific example, the discharge amount Q was 4.50A.

The above embodiment (hereinafter referred to as the first embodiment)
Is the upper half HU of the vehicle body side where the pillar structure occupies most
As for the lower half part HL, the coating gun 7 was reciprocated up and down to perform coating.
In order to be able to point in various directions, with respect to the painting arm,
By attaching the main body of the coating machine so as to be rotatable about the longitudinal axis of the front-rear axis, when coating the upper half HU, the coating gun is caused to perform a robot operation along the pillars of the vehicle body, and the coating on this portion is further performed. It can be done efficiently. The second embodiment of the present invention will be described below.
In the following description, the same parts as those in the first embodiment are designated by the same reference numerals and further description will be omitted. The method of dividing the coating area and the coating order of each coating block in this embodiment are the same as those in the first embodiment.

FIG. 7 and FIG. 8 show the movement locus of the coating gun when the coating gun is made to behave robotly along the pillar portion of the upper half of the vehicle body of the present embodiment, and the direction in which the coating gun is conveyed. It is explanatory drawing showing an example of each movement pattern, but the coating gun moved to the coating block of the upper half HU of the vehicle body is positioned at the lowermost end a of the center pillar 21 as shown in each of the above figures. Starting from this point a, it once rises along the center pillar 21 and then falls again to the lower end side b of the center pillar. After that, it moves forward and rises diagonally backward from point c along the front pillar to point d, and then moves along the roof rail to point e. Next, after descending diagonally backward along the rear pillar, the coating is completed by moving from point f to the lowermost end of the center pillar.

In this case, the spray pattern is controlled so that the major axis of the flat pattern is always orthogonal to the pillar, as shown by the broken line in FIG. Therefore, if the pillar width is not more than a certain degree, the pillar can be covered with a sufficiently thick coating film thickness of the coating pattern, and in this case, the number of times of coating can be once. Further, in this case, the coating blocks H ₁ and H _{2 of the} lower half portion HL of the vehicle body are coated while reciprocating the coating gun in the vertical direction as in the case of the first embodiment. Instead of moving the coating gun in the above order, for example, point b → d → c → a
You may move in the order of → e → f → a.

Explaining with a concrete example, for example, the total length of the movement distance in the robot operation with respect to the portion along the pillar of the vehicle body is 5000 mm, and the attitude of the coating gun is changed seven times in one cycle. The time required for the change was 0.3 seconds, and the tip speed Vg of the coating gun in this robot operation was limited to 20 m / min. Therefore, the coating time required to coat the upper half coating block HU for one vehicle is 17.1 seconds. Also, for the entire side surface of the vehicle, the painting time per vehicle is 1.53 minutes. In this case, the paint discharge amount Q when the paint block HU in the upper half of the vehicle body is painted is expressed by the following equation. Q = Vg · W · A (where A is a constant term) In this example, the coating pattern width W is 300 mm (0.3 m), and the paint discharge amount Q at this portion is 6.0 A.

Next, various comparisons will be made between the coating method according to the first embodiment (the first embodiment of the present invention) and the second embodiment (the second embodiment of the present invention) and the conventional coating method in which the coating gun does not perform the tracking operation. The evaluation results of comparative evaluation with the examples will be described. The characteristics of the coating method, various setting conditions, and evaluation results in each comparative example are shown in Table 1.

[0051]

[Table 1]

In Comparative Examples 1 to 3, the vertical reciprocating stroke of the coating gun is set according to the central portion of the vehicle body (the side surface of the passenger compartment) having the longest vertical length without variably controlling the stroke. Before and after that area, spraying is partially stopped and only stroke operation is performed,
The entire side surface of the vehicle body is coated. In Comparative Example 1, the gun tip speed, pass pitch and paint discharge amount are used, in Comparative Example 2, the pass pitch and coating time per unit, and in Comparative Example 3, the gun tip speed and 1 unit. The coating time per hit was set to be substantially the same as that in the example of the present invention. In addition, each of the comparative examples 1, 2,
3, the vertical stroke length of the coating gun is 173
It was set to 0 mm.

In Comparative Example 4, the vertical reciprocating stroke of the coating gun is set according to the lower half portion HL of the vehicle body without variably controlling, and the upper half portion HU of the vehicle body is lowered without coating. Partial coating is performed on the side surface of the vehicle body while reciprocating the coating gun up and down only for the half portion HL. In this comparative example 4, the vertical stroke length of the coating gun is set to 1200 mm and the pass pitch is set. The same settings were made as in the case of the present embodiment.

In Table 1 above, each evaluation item was evaluated with respect to the following contents, and when the evaluation result was satisfactory, a circle was marked, and when unsatisfied, a cross was marked. Attached.・ Evaluation items: Evaluate whether the entire side of the car body can be painted. ○ is marked for the entire coating, and × is marked for the partial coating when it is necessary to coat the remaining part in a separate process. -Evaluation items: Evaluate whether the gun tip speed is appropriately suppressed. If the tip speed of the gun is too fast, the coating efficiency will be reduced and the mechanical drive mechanism for reciprocating the gun will be overloaded and the durability of the device will be reduced. -Evaluation items: Evaluate whether the pass pitch conditions are appropriate. In order to ensure the uniformity of the coating film, it is better to set this pass pitch to 1/4 of the coating pattern width.・ Evaluation item: Evaluate the discharge amount of paint. The smaller the amount, the better.・ Evaluation items: Evaluate the coating time per unit. The shorter the painting time, the better.

As shown in Table 1, in the comparative examples, at least one of the evaluation items has an unsatisfactory evaluation, whereas in the examples of the present invention, satisfactory results are obtained in all the evaluation items. Was obtained.

As described above, according to this embodiment, the entire side portion of the vehicle body to be coated is divided into the vertical direction which is the reciprocating direction of the coating gun 7, and the lower half portion HL is divided into front and rear portions. Each of the coated blocks H ₁ and H obtained by dividing
By sequentially coating U and H ₂ , it is possible to coat the entire side portion of the vehicle body without causing unnecessary movement of the coating gun. Moreover, the reciprocating locus or movement of the coating gun 7 is variably controlled by the upper half HU and the lower half HL of the vehicle body in accordance with the curved surface shape of the surface to be coated or the shape of the coating portion in each coating area. So with one painting gun,
While keeping the coating thickness constant over the entire coating area,
It is possible to efficiently paint along the surface to be coated.

In each of the above-mentioned embodiments, the coating area on the side surface of the vehicle body is divided into three coating blocks H ₁ , HU, H _2. However, as the dividing method, there are various other modes. Can be considered. For example, as shown in FIG. 9, only the upper and lower parts may be divided into two parts, the lower half part HL and the upper half part HU may be painted.

Further, for example, as shown in FIG. 10, the upper half portion HU of the vehicle body is divided into front and rear portions to form the coating blocks H ₅ and H ₆ , and the lower half portion HL is arranged in the longitudinal direction of the vehicle body. one of the paint blocks _{H 1, H 2, H 3} , divided into H _4, may be coated separately in a total of six paint blocks. In this case, the coating order is H ₁ → H ₂ → H ₅ → H ₃
→ H ₆ → H ₄ or H ₁ → H ₅ → H ₂ → H ₆ → H ₃
→ The order of H ₄ is considered. In addition, by dividing the upper and lower coating areas HU and HL into the front and rear parts, respectively, the tracking amount when moving the coating gun from one coating block to another coating block can be further reduced. The device can be made more compact and space-saving.

Although each of the above-mentioned embodiments was applied to the coating on the vehicle body side portion of the automobile, the present invention
Not limited to the above case, as long as the length in the direction of reciprocating movement of the coating gun changes, it can be effectively applied to the coating work on all other objects to be coated.
Further, it is needless to say that the present invention is not limited to the above embodiments, and various improvements and design changes can be made without departing from the scope of the invention.

[Brief description of drawings]

FIG. 1 is an explanatory plan view of a coating apparatus according to a first embodiment of the present invention.

FIG. 2 is a front explanatory view of the coating device.

FIG. 3 is a side view of the coating device.

FIG. 4 is a vertical cross-sectional explanatory view showing a film thickness distribution in a pattern width direction of a coating film on a surface of an object to be coated.

FIG. 5 is a side view showing the coating block on the side of the vehicle body of the automobile according to the first embodiment.

FIG. 6 is an explanatory diagram showing an approximate curve of a curved surface of a vehicle body and a locus of a coating gun in an upper half portion and a lower half portion of a side surface portion of the vehicle body.

FIG. 7 is an explanatory diagram showing an example of a movement trajectory of a coating gun when coating a pillar portion of an upper half of a vehicle body of an automobile according to a second embodiment of the present invention.

FIG. 8 is an explanatory diagram showing an example of a movement pattern of a coating gun in the vehicle body transport direction when coating the pillar portion. It is explanatory drawing which shows the approximate curve of the vehicle body side part of the said vehicle body, and the locus | trajectory of a coating gun.

FIG. 9 is a side view showing a coating block on a vehicle body side portion of an automobile according to another embodiment of the present invention.

FIG. 10 is a side view illustrating a coating block on a vehicle body side portion of an automobile according to still another embodiment of the present invention.

[Explanation of symbols]

1 ... coating apparatus 4 ... coating machine main body 7 ... spray gun B ... body HU _{automobile, HL, H 1, H 2} , H 3, H 4, H 5, H 6 ... paint block

Claims (6)

[Claims] 1. A coating method for coating a conveyed coating object while operating a coating gun according to a predetermined locus, wherein the coating machine main body can be moved back and forth along the conveyance direction of the coating object. In addition, the coating gun is attached to the main body of the coating machine so that the coating gun can reciprocate in a predetermined direction, and the entire coating area of the coated object is divided into a plurality of coating blocks at least in the reciprocating direction of the coating gun. A coating method, wherein the coating blocks are sequentially coated while the reciprocating locus of the coating gun is variably controlled according to the coating blocks. 2. The coating gun is moved in the direction opposite to the coating direction when one of the coating blocks has been coated, and then coating of the next coating block is started. The coating method according to Item 1. 3. The coating method according to claim 1, wherein the coating area of the article to be coated is divided also in the conveying direction of the article to be coated. 4. A coating apparatus for coating a conveyed coating object while operating a coating gun in accordance with a predetermined locus, the coating apparatus being capable of moving back and forth along the conveying direction of the coating object. A coating machine body, a coating gun attached to the coating machine body so as to reciprocate in a predetermined direction, and the entire coating area of the object to be coated are divided at least in the reciprocating direction of the coating gun. Variable control means for variably controlling the reciprocating locus of the coating gun according to each of the plurality of coating blocks,
A coating apparatus, comprising: a movement control unit that sequentially moves the coating gun to each coating block. 5. A coating method for coating a conveyed coating object while operating a coating gun according to a predetermined locus, wherein the coating machine main body can be moved back and forth along the conveying direction of the coating object. And is attached to the main body of the coating machine such that the coating gun can reciprocate in a predetermined direction and is movable along the shape of the coating portion of the coating object, and the entire coating area of the coating object is at least the coating gun. The coating method is characterized in that the coating block is divided into a plurality of coating blocks in the reciprocating direction, and the coating blocks are sequentially coated while the operation of the coating gun is variably controlled according to the coating blocks. 6. A coating apparatus for coating a conveyed coating object while operating a coating gun in accordance with a predetermined locus, the coating apparatus being provided so as to be movable back and forth along the conveying direction of the coating object. The main body of the coating machine, a coating gun which is reciprocally movable in a predetermined direction with respect to the main body of the coating machine, and which is attached so as to be movable along the shape of the coating portion of the coating object, and the entire coating area of the coating object. Variable control means for variably controlling the operation of the coating gun in accordance with each of a plurality of coating blocks obtained by dividing at least the reciprocating direction of the coating gun, and movement control for sequentially moving the coating gun to each coating block. And a coating device.