JPH0676048A - Image pickup device for parts terminal detection - Google Patents

Abstract

PURPOSE:To discriminate the direction of parts by utilizing the property that the front end of a terminal pin of parts to be examined irregularly reflects the light from a light source by its cut end and illuminating only the front end of the terminal of parts to be examined and allowing the obtained image to pass prescribed recognition procedures. CONSTITUTION:Parts 20 to be examined is grasped and stationarily stopped in a light shielding wall part 22, which is so formed that almost all of parts 20 are not irradiated with light from an illumination part 23, by a parts grasping part 21, and only the front end part of the terminal attached to parts 20 is irradiated with light from the illumination part 23 when the image of the terminal projecting from parts 20 is picked up by an image pickup part 27, thus easily picking up the image of the terminal pin by a television camera.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an image pickup device for inspecting component terminals. More specifically, the present invention relates to an image pickup apparatus for inspecting the position, number, arrangement direction, etc. of terminal tips of a component having terminals such as lead components.

[0002]

2. Description of the Related Art In recent years, electronic devices have become lighter, thinner, shorter and smaller, and along with this, parts used for assembling these devices are
It is standardized as much as possible so that the automatic component insertion device can be handled easily from the design stage. However, there are still many processes that use irregularly shaped parts that cannot be standardized, and it is difficult to handle them with a dedicated automatic part insertion device. For this reason, generally, general-purpose assembling equipment such as robots are often used in the production process of electronic equipment. Furthermore, in order to inspect for missing or bending terminals of assembled parts and to detect the position and direction of parts, it is necessary to take images with a TV camera. After that, recognition processing of this is also generally performed.

Here, as the odd-shaped components to be handled, cylindrical transformers and the like are mainly used, and in many cases, the direction of insertion into the substrate is unclear even when observed from the upper surface. Taking this case as an example, a conventional technique will be described based on FIGS. 1 to 4 (a cylindrical transformer that is a deformed component and a pallet that stores the same).

The external appearance of the cylindrical transformer is as shown in FIG. 1, and usually, an insulated wire wound around a core (3) is covered with a polyethylene insulating film (2) for sealing. . A terminal pin (1) is mechanically attached to the core, and the insulated wire wound around the core can be fed with power from this terminal pin (1).

In such a transformer, the terminal pin (1) looks like a dot from the bottom surface as shown in FIG. 2, and the arrangement thereof has directionality. On the other hand, since the core (3) is simply covered with the film (2) from the top surface as shown in FIG. 3, it is not possible to obtain a clue to determine its directionality.

Further, in the assembly process, the transformer is usually placed and supplied with the bottom face down in the pallet chamber (6) divided into the pallet (5) as shown in FIG. Therefore, the direction of the parts cannot be determined while the transformer is in the pallet.

Conventionally, in the deformed parts arranged on the pallet as described above, the part (10) is once taken out by the robot manipulator (12) and placed on the ground glass (9) as shown in FIG. The camera (8) picks up the image from the bottom surface, and the direction is determined by image processing. This is because by adopting such a configuration, the image of the terminal pin portion can be detected as a dark spot because light from the illumination unit (11) in the obliquely upper portion is blocked, and the processing is facilitated.

Here, according to the prior art, when the plurality of terminals protruding from the component to be inspected have the same length, the rabbit does not come into contact with the ground glass. As shown in, the image of the contacted terminal (14) becomes lighter than the image of the contacting terminal (15), and this may not be detected during the recognition process. Therefore, all terminals are inspected. Therefore, the intended component direction cannot be determined. In particular, when the element to be inspected is inexpensive, the terminal length often varies, and if such an element cannot be automatically inspected, the cost of the assembly process may not be reduced.

On the other hand, by using an image pickup device such as a CCD device,
When inspecting the position and shape of the terminal tip of the part to be inspected, simply illuminating the part to be inspected produces an image other than the terminal tip to be inspected. Was difficult to inspect.

[0010]

SUMMARY OF THE INVENTION The present invention has been made in order to eliminate the above-mentioned drawbacks of the prior art. The purpose of the present invention is that the light emitted from the illumination section is the tip of the terminal of the inspected part. By holding the terminal tip of the part to be inspected so that it only hits, only the image of the terminal tip can be obtained clearly, and the position of the terminal can be reliably detected even if the terminal pin length varies. The present invention is to provide an image pickup device.

That is, in the present invention, the tip of the terminal pin utilizes the property of diffusely reflecting the light from the light source at its cut end,
By holding the part to be inspected so that the light emitted from the illuminating unit hits only the tip of the part of the part to be inspected, only the tip of the terminal of the part to be inspected is illuminated, an image of that is obtained, and after a predetermined recognition procedure, the part It is intended to determine the direction.

[0012]

An image pickup device for inspecting a component terminal according to the present invention comprises an image pickup section for taking an image and converting it into an electric signal.
An illumination unit that generates light including a frequency band to which the imaging unit is exposed, an inspection member gripping unit that grips a component to be inspected, and substantially the entire component to be inspected are formed so as not to be exposed to the light emitted from the illumination unit. And a light-blocking wall portion, the light emitted from the illumination unit is applied only to the substantially tip portion of the terminal attached to the inspected component when the imaging unit captures an image of the terminal emerging from the detected component. Thus, the inspected part is held.

[0013]

Here, the image pickup section can convert optical information into electrical information by using a television camera or the like and input it to the image processing apparatus. The illuminating unit that emits light including the frequency band that the image pickup unit sensitizes acts as a light source for causing diffused reflection at the tip of the terminal pin. Therefore, it is necessary to generate light of a color that can be accurately imaged by the imaging unit.

The light-shielding wall portion formed so that substantially the whole of the inspected component does not hit the light emitted from the illuminating portion acts so as to shield the light from the light source so as not to transmit to the back side of the light-shielding wall portion. . The inspection part gripping part that grips the part to be inspected allows the part to be gripped and transported, and prevents the bottom surface of the part to be inspected, which does not include the terminal pin, from being irradiated with light, It works so that it can move so that only the light hits it.

[0015]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described below with reference to FIGS. FIG. 8 shows the configuration of an embodiment of the present invention. The illumination section (23) generates irradiation light for illuminating the terminal pins of the inspected component (20). Therefore, the type may be a single light source, a plurality of light sources, or even an annular light source, but in order to obtain an image that is easy to process, an annular light source is used. It seems better to use. This is because the tip of the terminal pin can be captured as a circular image.

The component (20) to be inspected is such that the orientation of the component cannot be known unless the arrangement of the terminal pins is seen, and in this embodiment, the gripping direction of the component is detected. The terminal pin has a metallic luster because it is a conductor, and generally has a property of reflecting light even at its tip. Of course, some parts may have a coating on the tip of the terminal pin, and even in this case, if the coating has a surface gloss, it is expected that the same effect will be exerted in carrying out the present invention. be able to. The inspected part gripping part (21) has a tip capable of adsorbing the inspected part (20) by negative pressure and the other end connected to the action point of the robot, so that the inspected part can be freely moved. It can be transferred.

The image pickup camera (27) is a camera for taking in an original image used for recognizing the terminal pin positions of the parts to be inspected, and any method such as NTSC or SECAM can be used. Normally, the camera focuses on the tip of the terminal pin when the inspected component is in the inspection position, but the focus can be accurately adjusted even if it is easier to detect if it is slightly displaced due to the reflection condition of the terminal pin. There is no need to match it first. Further, by arranging the camera so that the image pickup is performed from below, it is possible to easily perform the inspection as it is taken out from the pallet.

The light shielding wall portion (22) is adapted to prevent the light emitted from the illumination portion (23) from entering the inside of the light shielding wall portion. Therefore, it is necessary to use a material that can substantially shield light. In addition, since it is not known in which direction the inspected part is facing, it is considered appropriate to use a cylindrical shape with the same diameter, but if it is inconvenient due to the surrounding equipment arrangement, take another shape. I don't mind.

The fixed stand (24) is provided with the light shielding wall (2
2) and the illumination unit (23) can be fixed to the mount (25). The background light-shielding part (26) is an umbrella attached to the inspection part gripping part (21) so that an unnecessary image does not appear around the inspected part in the image picked up from below. Therefore, it is not necessary to confine the shape to an umbrella shape (conical shape) as shown in the figure, but it is desirable to apply a black matte coating treatment or the like inside.

Next, the inspection operation according to this embodiment will be described with reference to FIGS. First, the robot takes out the parts to be inspected from a pallet (not shown), passes through the inside of the cylinder of the light shielding wall part (22) from the upper part of the light shielding wall part, and uses the part to be inspected (21) to make the terminal pin tips slightly shield the light shielding wall. Lower it until it reaches the position of the bottom end of the section. At this position, the background light-shielding portion (26) covers the upper end of the cylinder of the light-shielding wall portion (22) to prevent unnecessary light from entering from the outside. At this time, it is not known in which direction the inspected part faces. At this point, the imaging camera (27) can take an image for inspection.

Here, the positional relationship of each element when imaging for inspection becomes possible will be described with reference to FIG. The inspected component (10) is still held by the inspected component gripping portion (12), and the tip of the terminal pin stands still at a position slightly near the lower end of the light shielding wall portion (22). The light emitted from the illumination light source (30) included in the illumination unit (23) is a condenser lens (31).
Through, the tip of the terminal pin (1) of the inspected component (10) is irradiated.

At this time, although the light from the optical path A (32, 32) reaches the element to be inspected, the light from the optical path B (33, 33) is the light at the boundary position which is blocked by the light shielding wall, and this is the main body of the element to be inspected. Unless this happens, only the tip of the terminal pin (1) of the inspected component (10) is irradiated. Of course, since the light on the optical path B is diffracted at the lower end of the light shielding wall, it slightly hits the element body to be inspected, but since the illuminance is not high, the image obtained by the imaging camera and
It will not be detected as a characteristic part in the binarized image.

An image obtained by this positional relationship is shown in FIG.
It becomes like 1. Here, the background image (42) is a portion with the lowest illuminance, and the residual image (40) is a portion of the bottom surface of the inspected element visible due to the diffracted light. However, this can be removed in the processing of the image processing apparatus described later. Since the terminal pin tip image (41) is the reflected light of the illumination light source, an image with considerable brightness can be obtained, and its removal processing is extremely easy.

As another imaging example, the one shown in FIG. 12 may be obtained. Here, (51) to (53) are images of the tips of the terminal pins. The half-moon image (51) is a normal image of the terminal pin tip. When the tip of the terminal pin has a hemispherical shape, the spherical surface in the direction of the light source is reflected, so that the terminal pin has such a shape.
Although this is an image when the camera is focused on the tip of the terminal pin, a circular image is obtained when the camera is slightly displaced or intentionally filtered by a blur filter. Further, if an annular illumination is used for illumination, a circular image can be obtained in the same manner.

The circular image (52) is a normal image when the tip of the terminal pin is obliquely cut. If the tip of the terminal pin has a plane cut by cutting, a circular reflected image can be uniformly obtained. This is because light is reflected on the entire surface of the cut as shown in FIG. The deformed oval image (53) shows that the tip of the terminal pin is deformed in some way. This modification includes bending of the terminal pins.

By the way, there are cases where the grip position of the inspected component (10) gripped by the inspection component gripping portion becomes uncertain. This often occurs when styrofoam is spread all over the pallet, there is a step in the pallet compartment, and the mounting heights of the parts to be inspected are different from each other. In such a case, in the conventional example (FIG. 5), the component to be inspected is once placed on the frosted glass and re-gripped to adjust the height.

In the present embodiment, if this is necessary, FIG.
As shown in FIG. 4, a transparent plate (70) that transmits light may be arranged in the gap between the illumination section (23) and the light shielding wall section (22). That is, if the transferred parts (10) are once placed on the light transmission plate (70) and gripped again, the height can be adjusted. In addition to the above-mentioned inspection for each pin, it is also possible to confirm the bending or loss of the pin itself by measuring the pin interval.

The image obtained in the above embodiment may be processed by a known image processing apparatus. FIG. 13 shows this configuration. In the present embodiment, the image obtained by the image pickup camera (27) is temporarily stored in the image memory (60) of the image processing apparatus, and the CPU (61) is stored according to the program stored in the ROM (63). Performs binarization. By this binarization, it is possible to remove an unnecessary low brightness background image and the like. The CPU subsequently performs recognition processing on the remaining tip image of the terminal pin, and the predetermined inspection process can be completed. The inspection result is transferred to the numerical controller of the robot through the communication interface (62) so that the robot can perform the subsequent processing.

[0029]

As described above, according to the present invention,
By holding the terminal tip of the inspected part so that the light emitted from the illumination unit hits only the terminal tip of the inspected part, only the image of the terminal tip can be obtained clearly and the terminal pin length variation Even if there is a certain one, the position can be surely detected. Since the present invention can be applied to many parts with terminals, its effect is extremely large.

[Brief description of drawings]

FIG. 1 is an overall perspective view of a component to be inspected.

FIG. 2 is a bottom view of the inspected component.

FIG. 3 is a top view of a component to be inspected.

FIG. 4 is a diagram showing a state in which parts to be inspected are arranged on a pallet.

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

FIG. 6 is a diagram showing how light is reflected at the tip of a terminal pin of a component to be inspected.

FIG. 7 is a diagram showing an image obtained when there are variations in terminal pin lengths of a component to be inspected in a conventional example.

FIG. 8 is a diagram showing an example of the present invention.

FIG. 9 is a perspective view showing a positional relationship immediately before image capturing according to an embodiment of the present invention.

FIG. 10 is a cross-sectional view showing the positional relationship immediately before imaging, which is one embodiment of the present invention.

FIG. 11 is a diagram showing an example of an image obtained in one example of the present invention.

FIG. 12 is a diagram showing another image example obtained in one embodiment of the present invention.

FIG. 13 is a diagram showing a configuration example of an image processing apparatus connected to one embodiment of the present invention.

FIG. 14 is a diagram showing another embodiment of the present invention.

FIG. 15 is a diagram showing an optical path when a tip of a terminal pin of a component to be inspected is obliquely cut.

[Explanation of symbols]

 21 inspection part gripping part 22 light-shielding wall part 23 illuminating part 27 imaging camera

Claims (3)

[Claims] 1. An image pickup unit for taking an image and converting it into an electric signal, an illumination unit for generating light including a frequency band sensitized by the image pickup unit, an inspection component holding unit for holding an inspection target component, A light-shielding wall portion formed so that substantially the entire inspection component does not hit the light emitted from the illumination unit, and the light emitted from the illumination unit when the image pickup unit images the terminal protruding from the component to be inspected. An image pickup device for inspecting a component terminal, wherein the inspected component is held at a position where is irradiated only to a substantially tip portion of a terminal attached to the inspected component. 2. The imaging device for inspecting a component terminal according to claim 1, further comprising a light transmitting plate on which the inspected component can be temporarily placed, and a terminal protruding from the inspected component. Arranging the light transmitting plate so that the component to be inspected can be placed at a position where the light emitted from the illuminating part is emitted only to the substantially tip portion of the terminal attached to the component to be inspected when the image capturing section captures an image. An imaging device for inspecting component terminals. 3. Claims 1 or 2
The imaging device for inspecting a component terminal according to claim 1, wherein the light shielding wall portion is a cylinder having a light shielding property.