JPH0353024B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is applied to an automatic painting line in which atomized paint ejected from a spray gun is applied to a workpiece conveyed by a conveyor. This invention relates to a device that detects when a person approaches a spray gun abnormally.

Problems to be Solved by the Prior Art and the Invention In automatic painting lines, objects to be coated are suspended from hangers on a conveyor, so they are conveyed in a state that is highly inclined with respect to the conveyance direction and protrudes laterally. If you continue to transport it, not only will the coating be uneven as it will move diagonally to the spray gun, but if the amount of lateral protrusion is large, it will collide with the spray gun and cause damage. In particular, in electrostatic painting where high voltage is applied between the spray gun and the object to be painted, there is a risk of fire. equipment is required.
In electrostatic painting, the current value flowing from the spray gun nozzle increases as the object to be coated approaches, so a high-voltage generator measures this current value and determines abnormalities based on its absolute value, rate of increase, and amount of increase. Abnormal approach was detected by using the safety mechanism of There is a drawback that the distance cannot be judged accurately, and there is no device for detecting abnormal approach other than electrostatic coating, and the appearance of this type of device has been desired.

The present invention has been made in view of the above points, and can be applied to automatic painting lines other than electrostatic painting, and can accurately detect abnormal approach of the object to be painted to the spray gun. The object of the present invention is to provide an abnormal approach detection device for an automatic painting line that can perform the following steps.

Means for Solving the Problems In order to achieve the above object, the present invention sprays atomized paint from a spray gun installed near a conveyor that transports objects to be coated in a substantially horizontal direction. In an automatic painting line configured to apply paint to a surface, an ultrasonic distance measuring device is installed at or near the spray gun, and a detection range is set near the side of the spray gun where the object to be painted approaches; The structure is configured to detect the intrusion of the object to be painted into the detection range.

Function: An abnormal approach detection range is set on the side of the spray gun where the object to be painted approaches, and an ultrasonic distance measuring device measures the distance to the object to be painted.
Based on this measured value, it is determined that the object to be painted has entered the detection range, and abnormal approach is detected.

Embodiment Hereinafter, an embodiment of the present invention will be described based on the accompanying drawings.

In the figure, 1 is a conveyor that suspends a plate-shaped workpiece a from a number of hangers 2 hanging at regular intervals and conveys it in the horizontal direction shown by the arrow in the figure.
A support member 10 that is driven in the vertical direction by a drive mechanism (not shown) is attached to a reciprocating drive device 3 erected nearby, and the end of the support member 10 protruding from the side groove 4 of the reciprocating drive device 3 has a Support rods 11 that intersect at right angles are attached, and the support rods 11
L-shaped mounting rods 12 are attached so as to intersect at right angles to each other, and the spray gun 5 is mounted horizontally by fitting the mounting portion 6 at the rear end onto the vertically rising tip of the mounting rod 12. The spray gun 5 is mounted in a horizontal position by the reciprocating drive device 3, with the paint spout 7 at its tip facing the conveying path of the object to be painted with a distance therebetween. During this time,
Atomized paint is ejected from the ejection port 7 and applied to the surface of the object to be painted a.

An ultrasonic distance measuring device 8 is provided at the tip of the mounting rod 12 that protrudes above the mounting portion 6 of the spray gun 5. The device measures the distance to the object by emitting ultrasonic waves and receiving reflected waves from the object within a measurement angle of 60°. Mounting rod 12
and the fixing screw 13 so that the center line of the measuring angle of the transmitting/receiving part 9 faces at an angle of 30° toward the side where the object to be coated a approaches the spray gun 5. The distance measuring device 8 has a control device 1 whose measured value is inputted to the distance measuring device 8.
5 is connected, and the control device 15 adjustably sets the abnormal approach detection distance l, which is taken into consideration from the point of uniform coating of the object to be coated and safe transportation. As shown in FIG. 2, within the measurement range of °, an abnormal approach detection range A is set within a distance l from the transmitting/receiving unit 9, and the measurement value from the distance measuring device 8 is set at a preset detection distance. l
When the value falls below the value of An alarm device (not shown) connected to 15 is activated, and an abnormality is notified by a buzzer or lamp (not shown).

Next, to explain the operation of this embodiment, as shown in FIG. When the spray gun 5 is transported in a state where the spray gun is conveyed, and one of its protruding ends approaches the spout 7 of the spray gun 5 from the side and enters the detection range A,
Since the measured value is less than the detection distance l, the control device 15 sends an abnormality signal.

When measuring the distance to the object to be painted, in order to ensure accuracy, it is desirable to send an abnormal signal when the measured value falls below the value of the detection distance l twice in a row. In this case, for example, if the ultrasonic emission interval is 1/125 seconds and the conveyance speed of object a is 1 m/s, then the time required from the time object a enters detection range A until it is detected is The time is 2/125 seconds at most, and the distance that the object to be painted a moves during this time is only 16 mm or less, so in practice, the abnormality signal is not sent too late.

In addition, when changing the detection range A, the detection angle can be adjusted by replacing the transmitting/receiving section 9 with another transmitting/receiving section with a different measurement angle, and the relative angle made with respect to the spray gun 5 can be adjusted using the fixing screw. 13 and rotate the distance measuring device 8 around the mounting rod 12, the detection distance l can be further adjusted by loosening the control device 15.
By adjusting the setting knob 16 of
Since each can be changed, any detection range can be set by adjusting these.

In this embodiment, the distance measuring device 8 is attached to the mounting rod 12 into which the spray gun 5 is fitted, but instead of this, the distance measuring device 8 may be attached directly to the spray gun 5.

The present invention is not limited to a painting line in which the spray gun 5 reciprocates up and down as in this embodiment, but can also be applied to a painting line in which the spray gun 5 is fixed at a fixed position. This can be applied to all automatic painting lines using spray guns, regardless of the painting method such as electrostatic painting or airless painting.

Effects of the Invention As specifically explained in the above embodiments,
The abnormal approach detection device for an automatic painting line of the present invention includes:
Since an ultrasonic distance measuring device is used, the distance measuring function is not impaired even in a painting booth filled with paint particles where an optical distance measuring device cannot be used, and also on an electrostatic painting line. Ultrasonic waves can measure distances without being affected by high voltage like electromagnetic waves or by the shape and size of the object to be coated or the humidity in the painting booth like the current value of a spray gun nozzle. This has the effect of accurately detecting abnormal approach of the object to be painted to the spray gun.

[Brief explanation of drawings]

FIG. 1 is a perspective view of one embodiment of the present invention, and FIG. 2 is a partially cutaway plan view thereof. 1: Conveyor, 5: Spray gun, 8: Distance measuring device, A: Detection range, a: Object to be painted.

Claims (1)

[Claims] 1. In an automatic painting line in which atomized paint is ejected from a spray gun installed near a conveyor that conveys objects to be painted in a substantially horizontal direction and applied to the objects to be painted, the spray gun or the vicinity thereof An ultrasonic distance measuring device is attached to set a detection range near the side of the spray gun where the object to be painted approaches, and an intrusion of the object to be painted into the detection range is detected. An abnormal approach detection device for automatic painting lines featuring: