JPH0410389B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Industrial Application Field> The disclosed technology belongs to the technical field of applying a sealer material or the like to the joints of objects to be coated such as automobile body panels.

<Prior Art> As is well known, for example, in the process of painting the body of a car at a car manufacturing factory, in order to form the body, a sealing material is applied along the joints of predetermined panels joined by spot welding or the like. There is application work such as applying high viscosity filler such as sealer as a countermeasure against precipitation leakage around the body,
It is also used as a technology to prevent the occurrence of rust and corrosion.

Therefore, in the case of a conventional high-viscosity coating device that automatically applies a high-viscosity material to the joints of such panels, such as a playback type coating robot, the joints of panels are Due to misalignment of the conveyor, etc., misalignment between the body and the trolley or jig during loading, and assembly errors of the body itself, each unit of an automobile body has a considerable amount of damage. Misalignment is unavoidable, and therefore, it is difficult to maintain a constant relative position between the body and the coating device during coating work and to accurately apply the sealer material to the joints of the panels. Ta.

In particular, the application of sealants to parts of an automobile body that have complex curved surfaces, such as doors, hoods, and trunk lids, has traditionally been done manually due to the above-mentioned errors and installation errors. However, it was difficult to apply sealant along narrow seams, and it was difficult to ensure accuracy.

As a result, the following systems have recently been devised to cope with the application of high viscosity materials to automobile bodies.

That is, one of the methods is to set a coating device on the body shell or a door panel installed thereon, detect the positional deviation of these, and use the detected amount of positional deviation as a correction amount in the operation program of the coating device. In addition, by inputting a detection signal of the detected positional deviation between the panel seam and the target point of the coating device as a feedback signal to a system or coating device that eliminates positional deviation before coating, the seam can be corrected. There are systems that have a control function to match the aiming point.

<Problem to be solved by the invention> However, in the native system of the species,
When the coating device is used on a curved surface of a workpiece, especially a structure having a complicated three-dimensional curved surface such as an automobile body, there is a disadvantage that the structure of the position detection section and the control section is complicated and expensive. In the former case, there is an operational inconvenience in that it takes time to detect and correct the operation program, leading to a loss of work time for the robot, and in the latter case, the detection part must be installed in or near the coating device itself. Therefore, there was an inconvenience that the detection part interfered with the body constituent members and the application range was significantly limited.

Therefore, due to practical reasons, it has been adopted to install a coating device suitable for each part specifically so that it can be applied to the widest possible area of the body. This not only increases the number of coating devices required, but also increases the number of processes, resulting in an increase in space and costs.Furthermore, since each coating device is dedicated to each part of the workpiece to be coated, changing the vehicle model is not recommended. The disadvantage is that it is less responsive to other situations.

Furthermore, there are various negative aspects such as the operation of the robot as the coating device is wasteful and the number of required steps is increased.

To date, there are only a limited number of robots that can coat workpieces with complex curved surfaces, such as door assemblies, at the speed and accuracy that was conventionally done manually. There are restrictions in terms of equipment, and furthermore, when teaching the sealing operation, a high accuracy of approximately ±1 to 2 mm is required for teaching each point, so there is an undesirable point that it takes a lot of time and effort to teach. .

Based on this background, commercially available industrial robots can be used as coating devices without modification, and furthermore, the device will not interfere with components with complex three-dimensional structures such as automobile bodies. Without,
Slim and compact structure takes up little space.
There has been a desire for a flexible, versatile, and low-cost coating device that can perform spray coating and copy spray coating with sufficient precision for each location without limiting the work process.

The purpose of this invention is to solve the technical problem of applying a high viscosity material to the joints of workpieces such as automobile bodies having complex three-dimensional curved surfaces based on the above-mentioned prior art, and to develop a special modification of commercially available industrial robots. The gun can be installed on workpieces such as automobile bodies without any interference with the complex components of the workpiece, and the work area can be specified or limited, allowing greater freedom of work. Expensive, necessary,
In addition, spray coating and copying spray coating can be performed with sufficient accuracy, and in addition, no excessive operating force is applied to the device over time, and the structure is simple and compact, making it small and lightweight, allowing for great flexibility in work. , which can demonstrate wide versatility and is highly reliable, has a low-cost coating system, minimizes the number of processes and robots, and reduces adjustment and teaching man-hours, making it suitable for various industrial product manufacturing industries. It is an object of the present invention to provide an excellent method for applying a high viscosity material that is useful in the field of application of molding technology.

<Means for Solving the Problems> In order to solve the above-mentioned problems, the structure of the present invention, which is in line with the above-mentioned object and whose gist is the scope of the above-mentioned claims, is to apply a high-viscosity material to the seams of workpieces, etc. In this method, if there is no reference plane parallel to the application area, the actuator provided on the gun body block is operated to move the linear motion bearing back into the anti-rotation groove provided along the nozzle shaft. The nozzle is directed to a predetermined sealing area, and the application device is operated to direct the nozzle to the seam for teaching and predetermined coating and spraying work, thereby creating a door panel assembly having a reference surface. When performing copy coating work on joints of hemming parts such as A, etc., rotate the guide cylinder, guide pin, and nozzle shaft together with the gun body by a predetermined angle, and rotate the nozzle tip with the guide pin in contact with the reference surface in a predetermined manner. The distance of the discharge port to the reference plane is adjusted to a predetermined distance by approaching and separating, and the coating and spraying operations are performed in a predetermined manner, and in this way, errors in the installation of components, positional deviations, trajectory errors, etc. are absorbed. Technical measures have been taken to make it possible to use both copy coating and spray painting.

<Function> Therefore, in the painting process in an automobile manufacturing factory, etc., the seam of a workpiece consisting of a plurality of members that are integrally formed while having a mutual positional relationship or posture relationship, etc. When applying a high-viscosity material to a material, if a reference surface that is approximately parallel to the joint of multiple members is located near the joint, a guide equipped with a nozzle for this reference surface is provided. The pin is extended, contracted, or rotated to move the nozzle close to and away from it, adjusting the distance and pressing it into contact, and the high-viscosity material is applied and sprayed so that the nozzle is directed at the joint. In addition, for joints in areas where there is no reference surface, the nozzle of the coating device is directed to the joint to apply and spray the high viscosity material to the joint.

<Example> Next, an example of the present invention will be described below with reference to the drawings.

As shown in FIG. 4, in a mode in which a sealer is applied to a predetermined portion of an automobile body 1 by a robot 2 serving as a sealing device, a coating device constituting the gist of the present invention is attached to the tip of a three-dimensionally moving wrist 3 of the robot 2. 4 is provided, and the details of its structure are shown in FIGS. 1, 2, and 3.

That is, a gun body 6 forming a block body 7 is attached to the base plate 5 of the coating device 4, and the gun body 6 serves as a discharge body for a sealer material as a high-viscosity material, and a sealer material (not shown) is attached to the lower side surface of the gun body 6. A sealer supply port 8 for supplying the sealer is opened, and a gun extension 9 is connected to the lower part thereof, which is fixed with a bolt (not shown) or the like.

Therefore, in the figure, the gun extension 9
A nozzle base 12 having a needle seat 11 therein is firmly screwed to the lower part of the nozzle 12 via a packing 10.
3 is held between the nozzle tip 14 and the nozzle holder 15.
It is fixed by screwing and pressing.

Further, a cylinder 16 is fixedly installed in the upper part of the gun body 6, and a needle shaft 17 is fixedly extended downwardly to the needle seat 11, and a piston 19 integrally fixed with a nut 18 is inserted through a ring packing 20. It is slidable within the cylinder 16.

Furthermore, an air supply port 21 for turning on the gun, which communicates with the cylinder 16, is provided on the midway side of the gun body 6.
A cylinder base 22 is fixed to the lower part of the cylinder 16 by bolts (not shown), and a cylinder cap 23 is also fixed to the upper part by bolts. The cylinder 16 is kept airtight by the O-ring 25.

On the other hand, the needle shaft 17 and cylinder base 2
An O-ring 26 is also inserted between the two, and a plate 27 is fixed and sealed.

Note that there is a gun on one side of the cylinder cap 23.
An off air supply port 28 is drilled and opened.

Furthermore, a pressure spring 29 is interposed between the cylinder cap 23 and the piston 19 to press the piston 19 downward to ensure a seal with the needle shaft 17.

In addition, a V-packet 30 and a V-packet retainer 31 are inserted and set in the gun body 6 to ensure sealing against the cross-sectional ring-shaped passage 34 of the nozzle shaft 33 and needle shaft 17 extending downward from the gun extension 9 to the nozzle 32. There is.

On the other hand, a swing shaft 35 is connected and fixed to the rear side of the gun extension 9, and is supported by a swing bearing holder 37 into which a ball bearing 36 is inserted, to move the block 7 of the gun body 6 within a predetermined angle. It is made to be able to pivot relative to the base plate 5.

As shown in FIGS. 2 and 3, the base end of a swing plate 38 is fitted onto the other end of the swing shaft 35.
They are pivotally connected via a pin 39.

A guide bush 40 is provided at the tip of the swing plate 38 and faces a guide bracket 41 fixed to the base plate 5.
A tension spring 42 is interposed between the guide bush 40 and the guide bracket 41, and urges the swing plate 38 to be pulled toward the guide bracket 41.

Furthermore, an air cylinder type swing regulating cylinder 43 is connected to the base plate 5 via a cylinder bracket 44, facing the middle part of the swing plate 38.
The tip of the rod 45 faces near the center of the swinging plate 38 and can freely come into contact with and separate from the swinging plate 38, so that it swings.

A groove 46 for preventing rotation is formed on the outer surface of the nozzle shaft 33 up to the lower end of the gun extension 9, that is, near the attachment part of the nozzle base 12, and a guide pin 47 is inserted into the nozzle shaft 33. A linear motion bearing 49 having a bracket 48 extending down to the tip nozzle 32 and integrally attached thereto engages in the detent groove 46 in a splined manner and slides up and down along the nozzle shaft 33 in its axial direction. It is mounted on a shaft for free movement.

On the other hand, a guide cylinder 51 as an air cylinder type actuator is fixed to a bracket 50 at the base of the swing shaft 35, and a floating joint 53 is provided at the tip of the rod 52, and a floating joint 53 is provided at the tip of the rod 52 to actuate the linear motion bearing 49. The guide pin 47 is connected to the base end of the bearing holder 54 via a bracket 48 so as to be non-rotatably movable up and down along the nozzle shaft 33.

Note that stoppers 55 and 56 are provided at the upper and lower ends of the nozzle shaft 33 to regulate the stroke of the linear motion bearing 49.

In the above-mentioned configuration, when the robot 2 sprays a sealer to the joints of panels at a predetermined portion of the automobile body 1, the operating range of the robot 2 as a sealing device is within the range shown in a fan shape by the dashed line in FIG. If so, the door panel assembly 57 and part of the floor can be used as a sealing work area.

When performing the sealer application work, as shown in FIG. There is a real precondition that the installation position is off by d, and the required work conditions are that, of course, it is necessary to apply the door panel assembly 57 more accurately than the floor etc. If the robot 2 has the precision that allows it to apply to the floor underneath, the door panel attachment 57
The same robot 2 and coating device 4 can perform coating with sufficient accuracy.

In this case, in view of the general structure, the floor has a peripheral structure that does not have a selection reference surface such as a hemming part 58 for the gun, and on the other hand, the door panel assembly 57 is normally as shown in FIG. As shown,
It has a hemming portion 58, and therefore has a structure in which the outer periphery thereof can be used as a reference plane.

Therefore, in the case of coating the floor part, first, high pressure air is supplied from a high pressure air source (not shown) to the guide cylinder 51 of the coating device 4 of the embodiment through the air piping, and the rod 52 is drawn in to cause the flow to flow into the rod 52. By raising the linear motion bearing 49 non-rotatably along the anti-rotation groove 46 of the nozzle shaft 33 using the bearing holder 54 connected via the bearing joint 53,
The guide pin 47 is slid up and back as shown in Figures 1 and 2, so that only the nozzle 32 faces the sealing part, and on the other hand, the swing regulating cylinder 43 is operated with high pressure air to move the rod 45 back and forth by the set stroke. This causes the swing plate 38 to
is connected to the guide bush 4 via the tension spring 42.
0, the block body 7 moves back and forth between the guide brackets 41, and therefore the block body 7 swings relative to the base plate 5 at a set angle around the swing shaft 35, and the nozzle shaft 33 also swings, thereby dispensing the coating onto the robot 2. After teaching the operation, the sealer material is supplied from the sealer supply port 8, and high-pressure air is supplied from the gun-on air supply port 21, and the needle shaft 17 is raised together with the piston 19 against the pressure spring 29. The sealer is sprayed onto the floor portion from the nozzle 32 to perform the application work.

In this state, even if there is no reference plane on the floor, that is, even if there is no copying operation, the robot 2
The movement of the tip of the nozzle 32 that faithfully follows the movement of the nozzle 32 can be obtained, and since there are no interfering structures around the tip of the nozzle 32, coating can be performed over a wide range around the floor part.

Next, when sealing the door panel assembly 57, high pressure air is supplied to the guide cylinder 51, the rod 52 is lowered, and the linear motion bearing 49 is non-rotatably moved along the anti-rotation groove 46 of the nozzle shaft 33. , move the guide pin 47 forward together with the bearing holder 54, and move the green hemming portion 58 approximately parallel to the sealing line.
The coating device 4 is brought into contact with the reference surface of the robot 2 so that the reproduction path deviation and the teaching deviation of the robot 2 are absorbed by the coating device 4.
On the other hand, regarding the swing regulating cylinder 43, the rod 45 is retracted by high-pressure air in addition to the above-mentioned operation, and the coating operation is performed with the swing plate 38 being able to swing freely left and right as shown in FIG. Performs teaching and coating work.

As shown in the cross section of FIG. 7, the outer periphery of the door panel assembly 57, etc. is formed with a hemming portion 58, and the width W between the seam 58' and the outermost periphery is
is formed to have a width of 10 to 12 mm in most parts, and therefore, as shown in FIG. 8, the distance between the guide pin 47 and the nozzle 32 covers this width to perform the sealer application operation.

That is, as shown in FIG. 8, the application device 4 is oscillated in the direction
By pressing the material against the outer periphery of the hemming portion 58 and performing the application operation along this, even if the door panel assembly 57 is misaligned, as shown by the two-dot chain line in FIG. In addition, even if the movement accuracy of the robot 2 is poor and there is a deviation in the movement trajectory, the application range is limited to the reference surface of the guide pin 47, but the seal can be applied a certain distance from the outer periphery, and the seal can be applied accurately. Sealing can be done.

By the way, as mentioned above, the width W of the hemming part 58 shown in FIG. 7 is 10 to 12 mm in most parts.
However, as shown in FIG. 10, the width may vary up to about 5 mm at the fold line portion of the panel or at the end of the hemming portion 58.

Therefore, when automated sealing is performed using the coating device 4 described above, in order to cover all parts of the hemming part 58, the sealing range is from 5 mm to 12 mm, as shown in FIG. Application of a wide range of sealer materials is required to cover a wide range of areas.
There is a problem that the amount of material used increases.

The following work procedure can be used to deal with this problem.

That is, normally, as shown in FIG. 8, the guide pin 47 is perpendicular to the hemming portion 58, and as shown in FIG. The robot 2 twists and rotates the applicator 4 by a predetermined angle, so that the guide pin 47 is positioned at right angles to the edge line of the
Since the nozzle tip 14 contacts the hemming portion 58 at an angle, the distance h between the nozzle tip 14 and the nozzle hole 59 is equal to the distance H.
Therefore, the distance between the nozzle hole 59 and the edge line of the hemming portion 58 can be controlled.

Therefore, even if the amount of sealer material ejected from the nozzle hole 59 is kept constant, the sealer material can be sufficiently applied to the seam 58' even in a narrow width, and as a result, the sealer material can be used economically. In addition, the sealer can be applied in a sufficient amount to the bent hemming portion 58 as shown in FIGS. 11 and 12, and an extra control mechanism is not required and the weight of the device can be reduced. .

Note that the embodiment of the present invention is not limited to the above-described embodiment, and various embodiments may be adopted, such as controlling the amount of advance and retreat of the needle shaft 17 according to the rotation angle of the coating device 4 to control the amount of sealer material discharged. It is possible.

Also, by replacing the lifting mechanism of the needle shaft in the gun block with a cylinder and providing an appropriate spraying mechanism, it is also possible to perform spray painting using the swinging action of the gun block and nozzle shaft with a swinging cylinder. It is.

<Effects of the Invention> As described above, according to the present invention, installation errors may occur when sealing joints of members such as body panels whose positions and orientations are complicated in the coating process in an automobile manufacturing factory. However, there is no influence at all, and the excellent effect of coating with the required and desired precision is achieved.

In addition, the robot used for sealing does not need to be modified with special control circuits, etc. compared to commercially available industrial robots such as playback type robots, and can be used as is, so the structure of the equipment used can be changed. It has the advantage of being simple, lightweight, and inexpensive to manufacture, occupies little space, can be installed compactly and simply, and is easy to handle.

In addition, because there are fewer restrictions on the applicable range during coating work, fewer dedicated sealing devices are required, which reduces maintenance management, minimizes the number of work process controls, and simplifies the overall system. It also has the effect of reducing costs.

Practically speaking, the coating spraying speed can be increased to the limit, resulting in highly efficient coating work and the excellent effect of dramatically reducing the number of teaching steps.

In addition, copying in hemming parts etc. can be done accurately,
Moreover, since no telescopic spring or the like is interposed between the nozzle shaft and the guide pin, so-called "stiffness" does not occur, and the operation can be easily performed accurately.

Furthermore, since the entire coating device can be rotated, it is possible to move the nozzle hole toward and away from the hemming portion at will, reducing the amount of coating material used, which in turn reduces material costs. There are also benefits.

Further, according to the present invention, the gun can reliably perform the desired coating work on each required part without interference with the constituent members of the workpiece, resulting in improved product accuracy. There is also the effect that it is possible to aim for.

Therefore, not only can the coating work be carried out while absorbing the above-mentioned installation errors, but there is also the effect of having the flexibility to perform spray coating using an oscillating ready-made product.

By linking the guide pin attached to the nozzle shaft with the linear motion bearing that engages with the anti-rotation groove of the nozzle shaft, the guide can be used to align the hemming part with the reference plane when sealing against the hemming part, etc. By rotating the robot after each application, it has the excellent effect of being able to accurately apply high viscosity material to a predetermined position using an economical amount of material. Moreover, as mentioned above, even if there is an error in installation, this can be absorbed three-dimensionally and the desired coating can be performed accurately, which is an excellent effect.

In addition, by non-rotatingly engaging the nozzle shaft with the linear motion bearing, the entire coating device can be rotated without the need for complicated approach and separation operations. Even when the joints are complicatedly curved, it has the excellent effect of being able to accurately apply or spray the curved seams while reducing the amount of coating material. be done.

[Brief explanation of drawings]

The drawings are explanatory diagrams of one embodiment of the present invention, in which FIG. 1 is a partial cross-sectional side view of the device, FIG. 2 is a front view of the same cross-section, FIG. 3 is a partial enlarged side view of the rocking device, and FIG. The figure is a top view of how the sealer is applied to an automobile, Figure 5 is a partial front view of the door assembly installation error, Figure 6 is a side view of the door assembly, and Figure 7 is the 6th
Fig. 8 is a side view explaining the proximity of the guide pin to Fig. 7; Fig. 9 is a rear perspective view of the door panel hemming portion; Figs. 10, 11, and 12 are various sealing modes for the door panel hemming portion. The back view corresponding to the embodiment, FIGS. 13 and 14, are diagrams showing the positional relationship between the guide pin and the nozzle tip with respect to the edge line of the hemming portion. 2... Robot, 5... Base plate, 35
...Rotating axis, 32...Nozzle, 6...Gun body, 4...Coating device, 33...Nozzle shaft,
46... Detent groove, 46... Guide pin, 49
... Linear motion bearing, 51 ... Actuator.

Claims (1)

[Claims] 1 In the method of applying high viscosity material to joints of workpieces, etc., if there is no reference plane parallel to the application area, an actuator provided on the gun body block is operated to create a detent groove provided along the nozzle shaft. Then, the linear motion bearing is moved backward to direct the nozzle at the tip of the nozzle shaft to the specified sealing area, and the applicator operates to direct the nozzle to the seam to teach and perform the specified coating and spraying operations. Then, when performing copy coating work on joints of hemming parts such as door panel assemblies that have a reference surface, the guide cylinder, guide pin, and nozzle shaft are rotated together with the gun body by a predetermined angle, and the guide pin is set on the reference surface. By rotating the nozzle tip while making contact with the nozzle tip in a predetermined manner, the distance of the discharge port to the reference surface is adjusted to a predetermined value by approaching and separating, teaching, and performing coating and spraying operations in a predetermined manner. A high-viscosity material application method that absorbs installation errors, positional deviations, trajectory errors, etc. and enables both copying and spraying and spray painting.