JPH079405B2 - Appearance inspection device - Google Patents

Description

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a visual inspection apparatus capable of visual inspection of electronic parts such as ICs and transistors by imaging.

2. Description of the Related Art Conventionally, when recognizing lead pins of electronic parts such as ICs and transistors, the appearance inspection apparatus shown in FIGS. 4 and 5 has been used.

Hereinafter, this conventional visual inspection device will be described.

In FIG. 4, 1 is an electronic component of the object to be inspected, 2 is a lead pin of the electronic component 1, 3 is an illumination source for illuminating the lead pin 2, and 4 is a line sensor for detecting light reflected from the lead pin 2. It is a camera. Further, in FIG. 5A, 5 is a line sensor area showing a range detected by the line sensor camera 4, and 6 is a light irradiation section of the illumination source 3.

Next, the operation of the appearance inspection device configured as described above will be described. The light emitted from the illumination source 3 is the lead pin 2
The light reflected by the line sensor area 5 is received by the camera 4. The output waveform T shown in FIG. 5B was obtained from the camera 4, and the lead pin pitch P, the number N of lead pins, and the lead pin width W were detected.

Problems to be Solved by the Invention In such a conventional configuration, since the recognition of the lead pin 2 is seen by the output waveform T shown in FIG. 5 (b), the lead pin 2 of the electronic part 1 to be inspected has an external bending defect or an internal bend. It was difficult to detect bending defects. Also, depending on the surface treatment state of the lead pin 2, for example, in the case of a lead pin having a solder dip, the surface of the lead pin becomes rounded by the solder dip, and when the irradiation light is reflected, it diffuses in various directions, and the line sensor camera Since the reflected light to be output as an output waveform cannot be received, it is difficult to detect the lead pin pitch P and the lead pin width W.

In addition, when the line sensor camera 4 is a two-dimensional sensor, for example, a charge-coupled device (CCD) camera, the lead pin is directly recognized as an image, the influence of diffusion of reflected light from the lead pin 2 is small, and the lead pin pitch P Therefore, it is possible to detect the lead pin width W, but it is not possible to detect the delicate outer bending or inner bending state of the lead pin 2.

It is an object of the present invention to provide an appearance inspection apparatus which has a simple structure and can inspect lead pins such as lead pin pitch, lead pin width, number of lead pins, lead pin shape, lead pin inner bend, and outer bend.

Means for Solving the Problems In order to achieve this object, a visual inspection apparatus of the present invention provides a camera for imaging an inspection object, an illumination system for irradiating the inspection object, and a reflection from the inspection object. It has an image reflection plate that guides light to the camera, and an adjustment plate that can be swung by an angle to change the amount of irradiation light and the irradiation direction from the illumination system, and recognizes the appearance state of the inspection object.

With the above configuration, the image of the object to be inspected is picked up by the camera, and for example, not only the pitch, width, shape and number of the lead pins of the electronic part to be inspected but also the lightness and darkness of the reflection image from the image reflection plate are detected. As a result, it is possible to recognize the inward bending and the outward bending of the lead pin.

Embodiment FIG. 1 is a sectional side view of an appearance inspection apparatus according to an embodiment of the present invention. The device configuration will be described below. 7 is CC
D camera, 8 is a light source such as a high-frequency fluorescent lamp, 9 is a light source cover attached near the light source 8, 10 is a rail cover, 11 is a low distortion image reflector, and 12 is an image reflector 11 inclined at a predetermined angle. A holding plate that holds at an angle, 13 is a transport rail for the object to be inspected, 14 is a rotatable adjusting plate, 15 is a supporting plate, and 16 is an adjusting plate 14
Is a mooring pin for rotatably attaching to the support plate 15.

The operation of this embodiment will be described below. By the light source 8,
The lead pin 2 of the electronic component 1 to be inspected is irradiated, and the irradiation light amount and the irradiation direction are adjusted by the adjusting plate 14 which can oscillate the irradiation light.
Guide to camera 7. Then, the CCD camera 7 detects an image on the upper surface as a direct image of the lead pin 2 and an image on the side surface as a reflection image through the image reflection plate. The lead pin pitch, width, and number are recognized based on the detected image. Further, when an image is recognized by the CCD camera 7, the mutual relationship between the illumination optical path S and the reflectance of the image reflection plate 11 can be easily adjusted to an appropriate state by changing the angle of the adjustment plate 14. After adjusting the irradiation light adjusting plate 14 in this way, the second
As shown in the drawing, the lead pin 2 has a shape of a normal body 2a, an outer curved body 2b, or an inner curved body 2c.
When viewed from the position of the D-camera 7, as shown in the example of the recognition image in FIG. 3, the lead pin image 17 in the state of inward bending has a low light reflectance, and thus the reflection image is dark and the image in the image processing 2
It can be compared and recognized with the lead pin in the normal state at the value-ized level. In addition, the image of the lead pin with the external bending defect
18 is the same as the comparative recognition of the lead pin image 17 with the inward bend, and can be directly recognized as the image 18a without passing through the image reflection plate 11, and the image recognition processing by the direct image 18a is appropriately binarized. 2 by doing at the level
The direction can be inspected, and a highly accurate recognition process can be obtained.

Although a CCD camera is used as an image sensor for picking up an image of the object to be inspected in the above embodiment, a camera using an image pickup tube may be used instead of the CCD camera.

As described above, according to the present invention, the amount of irradiation light from the light source and the irradiation direction are adjusted by the adjustment plate capable of swinging the angle, and the reflection image is recognized and processed through the image reflection plate. This has an effect that image recognition processing with high recognition accuracy can be performed in the mutual relationship between the reflectance and the image reflector.

[Brief description of drawings]

1 is a side sectional view of an appearance inspection apparatus according to an embodiment of the present invention, FIG. 2 is a side view of an object to be inspected, FIG. 3 is a front view of a recognition image projected on a monitor or the like, and FIG. FIG. 5 is a side sectional view of the appearance inspection apparatus of FIG. 5, and FIG. 5 is a view for explaining a typical output waveform from the line sensor camera. 1 ... Inspected object, 7 ... CCD camera, 8 ... Light source, 11 ...
… Image reflector, 14 …… Adjuster.

Claims (1)

[Claims] 1. An image reflecting plate provided with a predetermined inclination angle, a camera for picking up an image of an object to be inspected through the image reflecting plate, and an illumination system for irradiating the object to be inspected with an amount of light that can be picked up by the camera. And an adjusting plate that can be swung by an angle to change the amount of light emitted from the illumination system and the direction of irradiation.