JPH031086Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a liquid coating device using a simple industrial robot.

For example, there is an operation in which a certain amount of adhesive is applied all around the inner wall of a tank. If such coating work is performed manually, the amount of coating is not uniform along the entire circumference, making it difficult to obtain ideal quality.

Therefore, automatic liquid discharging devices are used.
The nozzle of this automatic liquid discharging device is driven by a copying device, moves along the inner circumference of the tank, and continuously applies a fixed amount of adhesive.

However, copying devices require a cam or template that has the same or similar shape as the coated portion of the workpiece, and when the workpiece changes, the cam or template naturally needs to be replaced. For this reason, in the production mode of producing a wide variety of products in small quantities, there are disadvantages in that a large amount of setup change time is wasted and equipment costs are also increased.

On the other hand, high-grade industrial robots for painting and welding perform the necessary painting and welding work by moving the nozzle, torch, etc. while always perpendicular to the workpiece by motion of the wrist. In such high-grade industrial robots, the rotation of the wrist is controlled, so that the nozzle and torch are always able to move perpendicular to the processing surface of the workpiece. Therefore, a fairly complex control program is required to control the robot, and a special mechanism is built into the wrist of the robot hand.

Of course, the above-mentioned high-grade industrial robots can also be used for applying liquids such as adhesives. However, such high-grade industrial robots are expensive and are not used for applying adhesives or the like, which is neither dangerous nor a particularly bad working environment.

Therefore, the purpose of the present invention is to use a relatively simple industrial robot and use a mechanical device to constantly keep the nozzle of the robot's head on the coating surface of the workpiece without controlling the wrist. On the other hand, it is possible to maintain it almost in the normal direction.

Based on the above object, the present invention provides a liquid discharging nozzle rotatably attached to the head of an industrial robot that moves along the coating surface of parts, etc., using a rotary joint. A contact body for direct copying of the coating surface is provided on the nozzle side of the robot, and when the head of the robot moves, the contact body is brought into contact with the coating surface in a substantially perpendicular state. At the same time, the nozzle is arranged to face the coating surface in a substantially normal direction. Since the direction of the nozzle is controlled by such mechanical means, there is no need for a complicated wrist mechanism in the robot head, and therefore linear interpolation, circular interpolation, etc. for wrist control are possible. This eliminates the need for special control programs and simplifies the electrical control of the robot.

Hereinafter, the structure and operation of the present invention will be specifically explained based on an embodiment shown in the drawings.

FIG. 1 shows a liquid coating device 1 of the present invention. This liquid application device 1 is an industrial robot 2.
A nozzle 4 for discharging liquid attached to the head portion 3 and a contact body 5 for copying the coated surface are arranged.

The robot 2 is, for example, a multi-joint polar coordinate type robot, in which a frame 8 is attached to a column 7 of a base 6, and a first arm 9 and a second arm 10 of this frame 8 are connected to vertical joint axes 11, 12.
These first arms 9
and the second arm 10 with each joint axis 11,
The drive motors 13 and 14 above 12 are configured to be able to drive each independently.

A vertically moving shaft 15 is rotatably and vertically movably supported by the head portion 3 at the tip of the second arm 10. This vertical movement shaft 15 is driven by a rotary drive motor 16 provided inside the frame 8. That is, the rotation of the rotary drive motor 16 is caused by pulleys 17 and 18 rotatably supported on the joint shafts 11 and 12, a pulley 19 fixed to the vertical movement shaft 15, and a timing belt 20 and a timing belt 20 wound around these. Slide bearing 21
is transmitted to the vertical motion shaft 15 by. Further, the vertical movement shaft 15 is driven by a cylinder 22 mounted inside the head portion 3 of the second arm 10. That is, this cylinder 22
The cylinder rod 23 is connected to the upper end portion of the vertically moving shaft 15 in a manner allowing its rotation. Further, the vertical motion shaft 15 forms a spline 24, is rotatable relative to the sliding bearing 21 of the head portion 3, and is supported so as to be slidable in the vertical direction in a non-rotating state. The nozzle 4 is rotatably supported with an inlet 25 interposed therebetween. This nozzle 4 is attached to a member on the lower side of the rotary joint 25, that is, a member on the nozzle 4 side, on the axis of the vertical movement shaft 15, and is bent in an L-shape at the lower part, and has a discharge opening. is oriented horizontally. The liquid passage 26 of the nozzle 4 is connected to a supply source 28 of liquid, for example, adhesive, via a pipe 27 through the rotary joint 25 and the interior of the vertical movement shaft 15.

As shown in FIG. 2, a horizontal guide bar 29 is attached to the back side of the nozzle 4. This guide bar 29 holds a support body 32 between the mounting side and the stoppers 30 and 31 at the tip, and a coil-shaped spring 34 is attached to the slide hole 33 of the support body 32.
It is supported slidably in the axial direction while interposing. This spring 34 is connected to an L-shaped support 32.
is always urged in the advancing direction, that is, in the direction of the nozzle 4. And this support body 32
As shown in the figure and FIG.
It is equipped with a letter-shaped arm 35, and this arm 35
A roller 37 as the abutting body 5 is rotatably supported by a shaft 36 at two tip portions thereof. These left and right rollers 37 are connected to the rotary joint 2
They are provided at left and right positions sandwiching the nozzle 4 when viewed from the direction of the rotation axis of the nozzle 5 . A pair of guide plates 38 are provided on the left and right sides of the head section 3.
When the nozzle 4 is rising, the pair of guide plates 38 sandwich the support 32 that is rising together with the nozzle 4, thereby restraining the nozzle 4 from freely rotating.

Next, the operation of the liquid coating device 1 will be explained.

The first arm 9 and the second arm 10 receive the rotational force of the drive motors 13 and 14, and the joint shafts 11 and 12
Performs a turning motion centered on . Also, the vertical movement axis 15
is in a state where it can move up and down by receiving the driving force in the vertical direction of the cylinder 22, and can also rotate relative to the head portion 3 of the second arm 10 by receiving the rotation of the rotary drive motor 16, and moves the workpiece 39 such as a part. The tip of the nozzle 4 is opposed to the application surface 40 in a perpendicular state.

Before the coating operation, the vertical movement shaft 15 is at the upper limit position. At this time, since the support body 32 is held between the pair of guide plates 38, the nozzle 4 is in a state where it cannot rotate about the vertical movement shaft 15. When starting the coating work, the nozzle 4 is lowered together with the vertical movement shaft 15 to the height of the work position in a space where the roller 37 does not hit the workpiece 39. Thereafter, the first arm 9 and the second arm 10 of the robot 2 make appropriate turning movements to advance the nozzle 4 to the coating surface 40 of the workpiece 39. At this time, the roller 37 simultaneously contacts the coating surface 40 of the workpiece 39 and restricts the direction of the guide bar 29, that is, the nozzle 4, to the normal direction of the coating surface 40. In this state, the robot 2 drives the first arm 9 and the second arm 10 to rotate the nozzle 4 to the workpiece 39.
is moved at a constant speed along the coating surface 40 of.
During this time, the liquid (adhesive) supply source 28 supplies the adhesive to the nozzle 4 via the piping 27, the fluid passage 26, and the rotary joint 25 based on a constant supply function. When the nozzle 4 moves along the application surface 40 of the workpiece 39, the left and right rollers 37
The nozzle 4 moves while contacting the coating surface 40.
is always regulated to be orthogonal to the coating surface 40. Therefore, regardless of the orientation of the head portion 3, the nozzle 4 rotates at the rotary joint 25, and its discharge port is always directed in the normal direction of the coating surface 40 of the workpiece 39. After the nozzle 4 has gone around the inner wall of the workpiece 39, it returns to its original position.
After retracting at this position, it moves up to the upper limit and waits for the next coating operation. Nozzle 4
Since the support body 32 is sandwiched between the pair of guide plates 38 when the nozzle 4 is in the raised state, the nozzle 4
This means that even if the first arm 9 and the second arm 10 turn, they will not turn in an arbitrary direction. Arm 3 above
5 is bent in a U-shape, but this is work 3
This is because even when the coating surface 40 of No. 9 changes to a convex curved surface, it is possible to continue the desired work.

In the above embodiment, the abutting body 5 is a rotatable roller 37 to reduce the resistance during contact, but the abutting body 5 may also be composed of a fixed member with low frictional resistance. can. Alternatively, the pair of arms 35 may be rotatably supported by a shaft 41 as shown in FIG. 5, and may be biased by a spring (not shown). In this case, the pair of arms 35 are prevented from approaching each other more than necessary by a grating 42 provided between the arms 35. Further, in the above embodiment, the contact body 5, that is, the roller 37 is set back from the tip of the nozzle 4, but the roller 37 is placed at the same position as the nozzle 4 or at a position further forward than the nozzle 4, depending on the shape of the workpiece 39. established in Note that the support body 32
If there is a possibility that the guide bar 29 may rotate around the guide bar 29, a sliding key or the like may be provided on the guide bar 29.

Further, in the above embodiment, the support body 32 is slidably supported by the guide bar 29 that is integral with the nozzle 4, but this support body 32 is provided integrally with the nozzle 4, and this support body 32 is provided integrally with the nozzle 4. The abutting body 5 at the part of the body 32
Alternatively, the roller 37 may be supported in a movable state in the advancing direction. Further, the industrial robot 2 is not limited to the articulated polar coordinate type, but may be, for example, a rectangular coordinate type.

In this invention, the rotatably supported nozzle is always oriented in the normal direction to the coating surface by the position regulation function of the abutting body that contacts the coating surface, so high-grade linear interpolation and circular arc Control functions such as interpolation are not required in the robot control device, and the above objective can be achieved with a popular robot. Furthermore, unlike conventional copying control, there is no need for cams or templates similar to the shape of the workpiece, making setup changes easy and simplifying control and management.

[Brief explanation of the drawing]

Figure 1 is a side view of the liquid coating device of the present invention, Figure 2 is a side view of the liquid coating device of the present invention;
The figure is an enlarged side view of the main parts of the device, Figure 3 is a front view of the abutting body, Figure 4 is a plan view of the abutting body, and Figure 5 is a support part of the abutting body and other parts. FIG. 1...liquid coating device, 2...robot, 3...
Head part, 4... Nozzle, 5... Contact body, 25...
...Rotary joint, 26...Liquid passage, 2
7...Piping, 29...Guide bar, 32...Support, 34...Spring, 35...Arm, 37
... Laura, 38 ... Information board.

Claims (1)

[Claims for Utility Model Registration] (1) A nozzle for discharging liquid is supported via a rotary joint on the head of a robot that moves along the coating surface of parts, etc., and a member on the nozzle side of the rotary joint , at left and right positions sandwiching the nozzle when viewed from the rotational axis direction of the rotary joint, the abutting body with parts etc. is urged forward and supported by a spring, and the liquid passage communicating with the nozzle is at least passed through the rotary joint. An adhesive, etc. that is formed up to the robot side and communicates with external piping so that the nozzle can be directed in a direction substantially normal to the application surface when the abutting body comes into contact with a component, etc. Liquid applicator. (2) A liquid applicator for adhesive or the like as set forth in claim 1 of the utility model registration claim, in which the abutting body is a roller.