JPH06160066A - Apparatus for visual inspection - Google Patents

Abstract

PURPOSE:To easily conduct the optimum inspection from an arbitrary direction with a small number of facilities. CONSTITUTION:Photographing means 4a, 4b for photographing a part to be inspected of an inspection object, illumination means 3a, 3b for obtaining their images, a robot for freely moving in a three-dimensional direction so as to arrange the part to be inspected of the object at a focus point of an optical system composed of the photographing means 4a, 4b and the illumination means 3a, 3b in a condition to hold another part not to be inspected of the object and an image processing means 2 for performing quality discrimination of the object on the basis of its processing result are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an appearance inspection device for inspecting the appearance of a three-dimensional object from all directions.

[0002]

2. Description of the Related Art Conventionally, there is an apparatus shown in FIG. 5 to FIG. 7 as an apparatus for automatically performing an appearance inspection such as a chipping defect occurring at each place of a three-dimensional object.

First of all, as shown in FIG.
Multiple cameras 54 in front of each part to be inspected
a, 54b, 54c and illuminations 53a, 53b, 53c are installed, and there is a device for judging the quality of image data obtained from each of these cameras 54a, 54b, 54c by image processing.

Further, FIG. 7 shows an actual flat plate 3-1134109.
2 is a schematic diagram showing the configuration disclosed in FIG. The pump 1 to be inspected is placed on the positioning device 72, and a camera 74 and a lighting device are held at the tip of the articulated robot 73 installed on the side of the positioning device 72. The lighting fixture can be moved in a three-dimensional and arbitrary posture. The operating range of the articulated robot 73 is set so that the pump 71 to be inspected can be observed from all directions. The image signal photographed by the camera 74 is sent to the image processing device 77 and subjected to image processing. Further, the image processed image data is sent to the personal computer 7.
The quality is judged by comparing it with the reference data taught in advance. In addition, the image processing device 7
7 and a personal computer 78 are provided with a system control panel 79 for giving a predetermined command.

[0005]

However, the former conventional example described above requires as many cameras as the number of inspection points. Therefore, for example, when inspection of many points is required, it is a large-scale facility. If there is a space limitation, it may be difficult to install the camera, which is a problem. Further, in the latter conventional example, the illumination device is held at the tip of the robot simultaneously with the camera. Therefore, in the case of inspecting an object by the transillumination method, it is necessary to hold a large illumination device 63 on the extension line of the field of view of the camera 64 as shown in FIG. there were. In this case, there is also a method of fixing the lighting device, but at this time the lighting conditions change depending on the position of the camera, and it is not possible to implement inspection from all directions with optimal illumination, which leads to a decrease in inspection accuracy. was there.

The present invention has been made in order to solve these problems, and when performing a visual inspection of a three-dimensional object, an external appearance that can be easily and optimally inspected from any direction with a small amount of equipment. An object is to provide an inspection device.

[0007]

In order to achieve the above-mentioned object, the appearance inspection apparatus of the present invention is shown in FIG.
With reference to FIG. 4, cameras 4a and 4b for picking up an image of a portion to be inspected of an inspection object, illumination devices 3a and 3b for irradiating light to obtain an image of the portion to be inspected, and an object to be inspected A robot that freely moves in a three-dimensional direction such that a portion to be inspected of the target object is held at a focus position of an optical system including cameras 4a and 4b and illumination devices 3a and 3b while holding a portion other than the portion with a hand 1a. 1 and an image processing device 2 for determining the quality of an inspection object based on image data obtained by performing image processing on images obtained by driving the cameras 4a and 4b and the illumination devices 3a and 3b.
It is characterized by being composed of and.

[0008]

[Operation] By driving a robot that freely moves in the three-dimensional direction, a portion of the inspection object which is not the inspected portion is held,
The inspected portion of the inspection object is arranged at the focal position of the optical system including the image pickup means and the illumination means, with the inspected portion facing the image pickup means, and the image pickup means obtains a clear image of the inspected portion. be able to.

By repeating such driving of the robot, it is possible to obtain an image from any direction, that is, a clear image of a plurality of inspection points.

[0010]

FIG. 2 is a schematic diagram showing the apparatus configuration of an embodiment of the present invention. Embodiments of the present invention will be described below with reference to the drawings.

In this embodiment, the appearance of the injection-molded product is inspected. First, FIG. 4 shows a schematic shape of an injection-molded product of this inspection object. The defect to be detected in this molded product is a chipping defect, and this chipping defect is almost determined by the position of the gate that injects the resin into the mold, and in this object, it is shown in Fig. 4 (1). --- Defects may occur at the seven locations shown in (7). Therefore, it is configured so that all of these seven locations to be inspected can be inspected.

A camera for picking up an image of a portion to be inspected of an inspection object is provided with a reflection camera 14a and a transmission camera 14b. These cameras are preset with an illumination method that can most clearly obtain an image of a defect that occurs at an inspected portion, and the reflection camera 14a depends on the inspected portion.
Alternatively, the robot and the image processing apparatus are programmed so that the transparent camera 14b is used properly.
Further, a transmissive / reflective illuminating device 13 is provided for illuminating when imaging with these cameras 14a and 14b. The cameras 14a and 14b and the transmission / reflection illumination device 13 are installed on a robot / illumination stand 24. Further, the articulated robot 11 is installed on the robot / lighting stand 24, and a molded product hand 11a for holding a molded product is provided at the tip thereof. The articulated robot 11 has the degree of freedom and size to move all the inspected portions of the object to the positions of the focal lengths of the cameras 14a and 14b. Also, molded product hand 1
As shown in FIG. 4, the la 1a is configured to hold a portion having no obstacle in any of the inspection portions. The articulated robot 11 is driven by a drive signal from the robot controller 21. Furthermore, the above-mentioned camera 14
The images obtained by a and 14b are subjected to defect determination by the image processing described later in the image processing device 12.
Information such as the result of this determination is displayed on the monitor 23, and a molded product determined to be a non-defective product is discharged to the non-defective product conveyor 28, and a molded product determined to be a non-defective product is discharged to the defective product chute 25 as a result of the determination. It

The operation of the appearance inspection apparatus of the embodiment of the present invention having the above configuration will be described below. First, the molded product molded by the injection molding machine 26 is taken out of the mold by the unloader 29, and the simple position is determined and fixed by the molded product receiving jig 27. The control panel 22 receives the discharge completion signal from the unloader 29 and outputs an operation start signal to the robot controller 21. The robot controller 21 is the control panel 2
In response to the operation start signal from 2, the molded product is lifted by the molded product hand 11a attached to the end of the articulated robot 11 while holding a portion other than the inspected part, and the molded product is The inspection points can be sequentially moved to the focus position of the camera. The selection of the camera at this time is made by a program installed in the robot controller 21 in advance. That is, the illumination system is set in this program according to the inspected portion, and the program is controlled to move to the focal position of the camera in each system.

When the robot completes the movement to the proper focus position of the camera in this way, the movement completion signal is output from the control panel 22 so that the image processing device 12 takes in the image from the camera. At this time, the reflection camera 1
Which of the 4a camera and the transmissive camera 14b is used to capture an image is preprogrammed in the image processing apparatus 12 in accordance with a program previously incorporated in the robot controller 21 described above.

Here, the image taken in the image processing device 12 is subjected to the determination of the molded product according to the processing procedure shown in FIG. The procedure will be described below. First, CCD
After the image from the camera 34 is A / D converted (STEP.1),
It is binarized with a preset threshold value (STEP.2). Here, the area within a preset rectangular area is measured (STE
P.3). Then, with the preset reference value (STEP.3)
It is compared with the area measured in (STEP.4), and if it is less than the judgment reference value, it is judged to be defective (STEP.5).

In this way, when it is determined that the defect is present,
A defect determination signal is output from the image processing device to the robot. The robot moves all seven inspected points to the focus position of the camera, and if a defect determination signal is output, the molded product is sent to the defective chute 25. If not, the molded product is delivered to the non-defective conveyor. After discharging to, return to origin.

In the embodiment of the present invention, the method of binarizing and measuring the area in the rectangular area is used as the method of judging the quality by image processing. Alternatively, a detection method according to the edge shape or the like may be used.

Further, the type of camera is not limited to CCD, but may be MOS or the like, and the illuminating device may be any one capable of obtaining an image of an inspected portion such as a fluorescent lamp or a halogen lamp. Needless to say, any number of cameras and lighting devices may be attached.

[0019]

As described above, according to the present invention, an image pickup means for picking up an inspected portion of an inspection object, an illuminating means for obtaining the image, and a portion of the object which is not the inspected portion are held. In this state, the robot that freely moves in the three-dimensional direction so that the inspected portion of the object is located at the focal position of the optical system including the image pickup means and the illumination means, and the obtained image is image-processed Since the image processing means for judging the quality of the inspection object based on the result is provided, the optimum inspection can be easily performed from any direction, and the inspection can be easily performed with a small amount of equipment. Can be done.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a configuration of an embodiment of the present invention.

FIG. 2 is a schematic diagram showing a device configuration in an embodiment of the present invention.

FIG. 3 is an explanatory diagram showing a processing order in the embodiment of the present invention.

FIG. 4 is a schematic shape of an object to be inspected used in an embodiment of the present invention.

FIG. 5 is a schematic diagram showing a device configuration of a conventional example.

FIG. 6 is a diagram illustrating a transillumination system used in a conventional example.

FIG. 7 is a schematic diagram showing the configuration of another conventional device.

[Explanation of Codes] 1 ... Robot 1a ... Hand 2 ... Image processing device 3a, 3b ... Lighting device 4a, 4b ... Camera

Claims (1)

[Claims] 1. An image pickup means for picking up an image of a portion to be inspected of an inspection object, an illumination means for irradiating light to obtain an image of the portion to be inspected, and a portion of the object which is not the portion to be inspected are held. In this state, the robot is freely movable in the three-dimensional direction so that the inspected portion of the object is arranged at the focal position of the optical system including the image pickup means and the illumination means, and the robot is obtained by driving the image pickup means and the illumination means. And an image processing unit that determines whether the inspection target is good or bad based on image data obtained by performing image processing on the image.