JPS6121711B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention provides a method for painting a workpiece transported in one direction by a transport device such as a conveyor using a spray gun that reciprocates in a direction substantially perpendicular to the transport direction. More specifically, the automatic painting device irradiates light onto a model having a shape corresponding to the object to be coated, and determines the relative position of the model and a photosensitive element that operates by receiving the reflected light or transmitted light. The object to be coated and the spray gun are moved in synchronization, and a photosensitive element is activated to control whether or not the spray gun sprays paint, so that paint is only sprayed while the spray gun is pointing at the object. Regarding automatic painting equipment.

Conventional automatic painting equipment reciprocates a spray gun in a constant stroke vertically with respect to the workpiece being conveyed horizontally, and operates a pair of upper and lower limit switches while the workpiece passes in front of the spray gun. Since the paint is sprayed only at a fixed interval above and below, which is regulated by
When painting object a shown in the figure, object a
The paint is sprayed over the entire area of the rectangle b whose two sides are the full length and maximum height of the object A, but the spray is wasted on the hollow part at the bottom center of the object to be coated, resulting in extremely poor results. It was the economy. For this reason, an attempt was made to divide the injection control range by using two or more pairs of upper and lower limit switches and the corresponding number of timers, and to regulate the paint injection range with a step-like outline as shown by the constant chain line c in the figure. Attempts were made to do this, but the combination of limit switch and timer
Not only is the number of divisions limited due to the mounting position, but increasing the number of divisions complicates the structure of the control device, and it also takes a long time to set up. It is impossible to control a step-like profile with small steps like c.
Because it has to be shaped like a staircase with a small number of steps,
Depending on the shape of the object to be coated, a considerable amount of paint may be wasted.

The present invention was developed in view of the above circumstances, and it is an object of the present invention to provide an automatic coating device that can control the spray range of paint extremely accurately and easily.

Hereinafter, one embodiment of the present invention will be described in detail based on FIGS. 2 to 4.

In Figures 2 and 3, 1 is a conveyor that conveys the object to be coated in the horizontal direction, 2 is a base installed perpendicular to the conveyor 1, and 3 is a conveyor that can be moved back and forth on the base 2 by means of wheels 21. The frame of the main body A placed thereon is moved back and forth by a hydraulic drive device 22 installed horizontally on the base 2, and two screws in the front and rear directions are rotatably supported on the base 2. Bar 23,2
4, respectively, and abut against stoppers 25 and 26 that move back and forth by the rotation of each threaded rod 23 and 24, so that the front and back positions are regulated. Inside the frame 3, a main plate 31 is provided with vertical guide rails 32, 32 formed on both sides, and a motor 34 with a transmission 35 and a reducer 3 are mounted on the rear surface.
7 are fixed vertically, and a belt 41 is stretched between a pulley 36 fixed to the output shaft of the transmission 35 and a pulley 40 fixed to the input shaft of the reducer 37. The output shaft 38 on the front side of the reducer 37 penetrates the main plate 31 and protrudes to the front, and a sprocket 42 is fixed to the tip thereof. A chain 44 is stretched across the sprockets 42 and 43 so as to circulate up and down between the two sprockets 42 and 43. Reference numeral 6 denotes an elevating platform that is supported in a vertically movable manner by sandwiching the guide rails 32, 32 on both sides of the main plate 31 with several rollers 61 installed on the rear surface, and has a horizontal relative movement within it. A freely supported plate 62 is fitted into a pin (not shown) fixed to the endless chain 44, and as the endless chain 44 circulates, it reciprocates up and down along the main plate 31. An arm plate 63 is horizontally fixed to the front surface of the lifting platform 6, and flat plates 64 are fixed to both ends thereof, and upper and lower links 6 are attached to the front surface of each flat plate 64.
5, 66, and a bracket 6 supported at the tip thereof.
A trapezoidal link mechanism 70 consisting of 7 is provided, and a spray gun 68 is mounted on the bracket 67.
is attached, the trapezoidal link mechanism 70 swings up and down by the drive device 69 attached to the base of the lower link 66, and the spray gun 68 moves to the position shown by the solid line and chain line in FIG. It is designed to change its posture upward and downward. Further, the output shaft 39 on the rear side of the reducer 37 is connected to the chains 51 and 52.
It is connected to a pulse transmitter 53 installed at the bottom of the frame 3 and a cam drive device 54 that rotates two plate cams 55 and 56. The plate cams 55 and 56 rotate once for each circulation of the endless chain 44, and one of the plate cams 55 is
When the lifting platform 6 reaches the uppermost position, the other plate cam 56 engages one contact of the limit switch 57, and the other plate cam 56 engages the other contact of the limit switch 57 when the lifting platform 6 reaches the lowermost position. The pulse transmitter 53 is adapted to transmit a pulse signal each time the elevator platform 6 moves a certain distance.

FIG. 4 shows an injection range control device installed in parallel with the main body A.

In the figure, reference numeral 82 denotes a movable table which is slidably supported by a horizontal sliding guide 81 formed on the front surface of the fixed table 8, and has a rack 83 formed on the upper surface and two models 85 on the lower surface. It is suspended by a thin string 84. This model 85 is the object to be coated a.
It is constructed to have a similar shape at a scale of 1/n. Reference numeral 86 denotes a first reversible pulse motor mounted on the fixed base 8, which rotates by a fixed angle each time it receives the end signal of the upward stroke and downward stroke of the spray gun 68 issued from the limit switch 57 of the main body A. When the total number of signals reaches a certain value, the conveyor 1 is rapidly reversed, and a pinion 87 fixed to its output shaft is engaged with a rack 83 of a moving table 82, thereby controlling the conveyor 1's feeding speed. The movable table 82 is intermittently moved forward in the horizontal direction at a speed of 1/n of , and is rapidly returned to the original position after moving a certain distance.

In front of the movable table 82, an elevating body 9 with a vertical rack 91 formed on its back surface is installed to be able to move up and down freely, and a light emitting element 93 is mounted on the upper stage of a vertical bar 92 erected at the upper end of the elevating body 9, and a photo-emitting element 93 is mounted on the lower stage. Photosensitive elements 94 such as transistors are each attached to face the model 85, and the luminous flux emitted from the light emitting element 93 is directed toward the model 85.
When the photosensitive element 94 is actuated by the received light, a solenoid valve (not shown) is opened in response to the activation signal, and paint is injected from the spray gun 68. When the pump stops, the solenoid valve closes and paint injection stops. Reference numeral 95 denotes a second reversible pulse motor, which rotates forward and backward at a speed proportional to the number of pulses emitted from the pulse transmitter 53 of the main body A, and finishes the upward and downward strokes of the spray gun 68 emitted from the limit switch 57. It has a structure in which normal rotation and reverse rotation are mutually switched by a signal, and a pinion fixed to the output shaft is engaged with a rack 91 of the elevating body 9, and the elevating speed of the spray gun 68 is 1/1/1. It is designed to rise and fall at a speed of n.

Next, the operation of this embodiment will be explained.

After a limit switch (not shown) installed at the entrance of the coating booth detects the passing of the object a, the conveyor 1 moves a certain distance and the leading edge of the object a in the transport direction reaches the front of the spray gun 68. As the spray gun 68 starts to move up and down, the first and second reversible pulse motors 86 of the control device,
95 is started, the model 85 moves horizontally at a speed of 1/n of the conveyance speed of the object a, and the elevating body 9 moves up and down at a speed of 1/n of the spray gun 68. The light emitting element 93 moves in such a manner that the relative position of the light emitting point with respect to the model 85 is always the same as the relative position of the paint injection point of the spray gun 68 with respect to the object a.
While the luminous flux emitted from the light emitting element 93 hits the model 85, the photosensitive element 94 receives the reflected light and operates, and paint is sprayed from the spray gun 68 for the duration of the light reception to the object to be coated a. When the paint is applied to the model 85 and the light beam leaves the model 85, the photosensitive element 94 stops operating and the spray gun 68 stops spraying the paint. When the trailing edge of the model 85 in the traveling direction passes in front of the photosensitive element 94 and the trailing edge of the object to be coated in the conveying direction passes in front of the spray gun 68, the spray gun 68 and the elevating body 9 return to the starting position and stop. At the same time, the first reversible pulse motor 86 is reversely rotated, and the model 85 is rapidly returned to its original position. When using the spray guns 68, 68 on both the left and right sides of the main body A at the same time, the spray gun 68 on the front side in the conveying direction of the object a is controlled to eject paint with a certain stroke delay from the spray gun 68 on the rear side. do it. Note that the light emitting element 9
3 and a photosensitive element 94 are placed opposite each other with the model 85 in between, and the light emitted from the light emitting element 94 is transmitted to the photosensitive element 9.
Whether or not the spray gun 68 sprays paint may be controlled depending on whether or not the light emitting element 4 receives light, or the light emitting element 93 may be omitted and natural light may be used. Furthermore, when the photosensitive element 94 has the directivity of receiving only the light flux entering from a certain direction, the cross-sectional area of the light flux emitted from the light emitting element 93 may be increased.

Next, another embodiment of the control device will be described based on FIG. 5.

In the figure, 8a is a fixed base on which a first reversible pulse motor 86a and a bearing 84 are mounted.
a, 84a are installed, and a drum 82a is fixed to a shaft 87a which is rotatably supported by bearings 84a, 84a, and a shaft 87a is connected to the output shaft of a first reversible pulse motor 86a. A model 85a with a scale of 1/n is pasted on the outer periphery. In front of the model 82a, there is a movable table 9a with a rack 91a formed on the lower surface of the shaft 87.
A light-emitting element 93a and a photosensitive element 94a are attached to a vertical bar 92a that is installed on the upper surface of the vertical bar 92a, and the light-emitting element 9
The light beam emitted from the model 85a is reflected by the model 85a and received by the photosensitive element 94a, and when the light beam deviates from the model 85a, it is absorbed by the surface of the drum 82a painted black and is prevented from being received by the photosensitive element 94a. It's getting old. In addition, the moving table 9a
is the output shaft 9 of the second reversible pulse motor 95a.
Pinion 96a and rack 91a fixed to 6a
The meshing allows reciprocating movement in the horizontal direction. First reversible pulse motor 86a
rotates at a speed proportional to the number of pulses emitted from the pulse transmitter 53 of the main body A, and is switched between forward and reverse by the end signal of the upward stroke and downward stroke of the spray gun 68 emitted from the limit switch 57, and the second The reversible pulse motor rotates forward by a fixed angle each time it receives the end signals of the upward stroke and downward stroke, and rapidly rotates reversely when the number of received signals exceeds a fixed value.

In this embodiment, the drum 82a rotates in alternate directions at a circumferential speed of 1/n of the vertical speed of the spray gun 68, and each time the drum 82a switches the rotation direction, the light emitting element 93a and the photosensitive element 94a of the spray gun By horizontally moving 1/n of the distance that the conveyor 1 moves during one stroke, the relative position of the light projection point with respect to the model 85a changes to the relative position of the paint injection point of the spray gun 68 with respect to the object a. The paint is injected from the spray gun 68 only for the time that the light beam emitted from the light emitting element 93a hits the model 85a and the reflected light is received by the photosensitive element 94a, and the light beam is kept at the same position as the model 85a. When it comes off, the light is not received by the photosensitive element 94a and the spray gun 68 stops spraying the paint.

In this embodiment, if two models 85a are attached upside down on the surface of the drum 82a,
It is sufficient to simply rotate the drum 82a in the same direction.

As clarified by the above explanation, the automatic coating apparatus of the present invention reciprocates the spray gun in a direction substantially perpendicular to the direction of conveyance of the object to be coated, with respect to the object to be coated that is being conveyed in one direction. In an automatic painting device that sprays paint at the same time, it has a model with a shape corresponding to the object to be painted, a light source that projects light onto the model, and reflected or transmitted light emitted from a part of a certain range that includes the model. A photosensitive element that receives light and operates, and a photosensitive element or a part that receives light such that the relative position of the part that the photosensitive element receives with respect to the model maintains the same relationship as the relative position of the pointing point of the spray gun with respect to the object to be coated. a drive device that relatively moves the light source and the model in synchronization with the transport movement of the object to be coated and the reciprocating movement of the spray gun;
The gist of the present invention is to control whether or not the spray gun sprays paint by operating the photosensitive element, and the paint is sprayed only while the spray gun is directed toward the object to be coated. Since it is possible to control objects with complex shapes without wasting paint, if the object to be painted is changed, it is only necessary to replace it with a model that corresponds to the shape. It has the effect of easy setup change and high operating rate.

[Brief explanation of the drawing]

The attached drawings show an embodiment of the present invention, in which Fig. 1 is a front view of an object to be coated, Fig. 2 is a partially cutaway front view of the main body of the coating device, Fig. 3 is a side view of the same, and Fig. 4 is a control device. FIG. 5 is a perspective view of another embodiment of the control device. 1...Conveyor, 68...Spray gun, 85,8
5a...Model, 93, 93a...Light emitting element, 94,
94a...Photosensitive element, 86, 86a, 95, 95a
...Reversible pulse motor, a...Object to be coated.

Claims (1)

[Scope of Claims] 1. An automatic coating device that sprays paint onto a workpiece being transported in one direction while reciprocating a spray gun in a direction substantially perpendicular to the transport direction of the workpiece, A model with a shape corresponding to the object to be coated, a light source that emits light onto the model, a photosensitive element that operates by receiving reflected light or transmitted light emitted from a part of a certain range including the model, and the photosensitive element The photosensitive element or the light source and the model are moved to convey the workpiece so that the relative position of the part receiving light with respect to the model maintains the same relationship as the relative position of the pointing point of the spray gun with respect to the workpiece. and a drive device that moves the spray gun relatively in synchronization with the reciprocating motion of the spray gun, and is configured to control whether or not the spray gun sprays paint by operating the photosensitive element. Device.