JP5553657B2 - Appearance inspection device - Google Patents

Description

  The present invention relates to an appearance inspection apparatus, and more particularly to an appearance inspection apparatus that images and inspects the outer peripheral surface of a long object to be inspected with a plurality of cameras.

Conventionally, the surface of a rod-shaped object is inspected by performing image processing on an irradiation unit that irradiates light on the object surface, a CCD camera that images an irradiated portion of the object surface, and a captured image captured by the CCD camera.
For example, an appearance inspection apparatus for inspecting the surface of a cigarette includes a hopper into which the cigarette to be inspected is put, a transport means for rotating and transporting the cigarette put into the hopper, and an inspection means for inspecting the surface of the cigarette that rotates. A tray for storing non-defective tobacco products and a discharge tray for storing defective products. The inspection means arranges the CCD camera and the irradiation means above the cigarette conveyance path, images one outer circumference of the cigarette rolling on the conveyance means, and the image processing means performs image processing on the picked-up image. Inspecting the surface.
That is, the entire outer peripheral surface of the cigarette is imaged by the CCD camera by rolling the cigarette.

  However, in the appearance inspection apparatus having the above-described configuration, since the inspection target is a short rod-like object, the entire periphery of the outer peripheral surface can be imaged by rolling the inspection target cigarette within the field of view of the CCD camera. However, when the length of the object to be inspected is long, for example, in the case of a long article manufactured by extrusion molding, the object to be inspected cannot be rotated because the article is continuously manufactured. . For this reason, it is not possible to inspect the entire region of the outer peripheral surface of the long object to be inspected. Therefore, a method of imaging the outer peripheral surface by rotating the CCD camera in the circumferential direction along the outer peripheral surface of the object to be inspected in the appearance inspection apparatus having the above configuration can be considered, but the apparatus configuration for rotating the CCD camera is complicated. turn into. In addition, depending on the molding speed of extrusion molding, only thinning-out inspection could be performed.

JP 05-180777 A

  In order to solve the above-described problems, an appearance inspection apparatus capable of inspecting all the outer peripheral surfaces of a long object to be inspected continuously manufactured with a simple apparatus configuration is provided.

As construction of the present invention, the resin material moves in the extending direction A visual inspection apparatus long object to be inspected as a raw material, a guide cylinder extending direction and the center axis of the inspected object are matched, the Five or more cameras that are arranged so as to surround the inspection object from the outside and are guided by the guide cylinder, and provided at the camera-side tip of the guide cylinder, An annular illuminator that illuminates the imaging position along the outer peripheral surface of the object to be inspected, and an image processing means for processing an appearance image of the object to be inspected in the extending direction by using five or more cameras It comprised so that.
According to the present invention, since the plurality of cameras are positioned so as to surround the object to be inspected, the entire outer periphery thereof can be imaged without causing imaging omission, and a highly reliable appearance inspection apparatus can be obtained. Moreover, since the outer peripheral surface of the inspection object to be imaged by the camera can be irradiated with light in the circumferential direction, the imaging accuracy can be further improved, and the configuration can be simplified and the cost can be reduced.
Further, as a configuration of the present invention, the imaging direction of the camera is arranged to be inclined from a direction perpendicular to the extending direction of the inspection object.
According to the present invention, since the imaging direction of the camera is slightly inclined, the captured image can be observed in a three-dimensional manner, and irregularities in the appearance can be detected, and the observation accuracy can be improved .
In addition, as a configuration of the present invention, the appearance inspection apparatus includes a positioning unit that positions the position of the camera with respect to the object to be inspected.
According to the present invention, since the camera can be positioned in accordance with various cross-sectional shapes of the object to be inspected, it is possible to deal with a variety of products.
As a configuration of the present invention, the appearance inspection apparatus includes an imaging cycle control unit that controls the imaging cycle of five or more cameras in accordance with the moving speed of the object to be inspected.
According to the present invention, since the imaging cycle control means controls the imaging cycle of each camera in accordance with the moving speed of the longitudinal object to be inspected, continuous imaging can be performed over the entire length, and high reliability is obtained. .
In addition, as a configuration of the present invention , a moisture removing member that removes moisture adhering to the inspection object is provided before the inspection object is imaged by the camera.
According to the present invention, since the appearance can be inspected in a state where the moisture of the object to be inspected is removed, it is possible to accurately observe without causing an error.

The schematic process side view to which the external appearance inspection apparatus of the shaping | molding tube which concerns on this invention is applied. The side view and front view of the external appearance inspection apparatus of the molded tube which concern on this invention. 1 is a detailed view of a molded tube appearance inspection apparatus according to the present invention. The principal part sectional view of the appearance inspection device of the forming tube concerning the present invention. The figure of a tube when the external appearance test | inspection of the shaping | molding tube which concerns on this invention is carried out.

  Hereinafter, the present invention will be described in detail through embodiments of the invention. However, the following embodiments do not limit the claimed invention, and all combinations of features described in the embodiments are inventions. It is not necessarily essential to the solution means, but includes a configuration that is selectively adopted.

  FIG. 1 is a schematic process side view showing an embodiment in which an appearance inspection apparatus according to the present invention is applied to an apparatus for manufacturing a tube A manufactured by, for example, extrusion molding as an object to be inspected. In FIG. 1, the forming process of the tube A includes a resin forming process in which the tube A is formed by an extruder 9, a cooling process having a cooler 14 that is cooled after the tube A is formed, and the formed tube A. It consists of a take-up process with a take-out machine not shown. As a material of the resin material 7 which is a raw material of the tube A, molybdenum resin, polypropylene (PP), polyethylene (PE), olefin plastic elastomer (TPE), styrene TPE, polyamide TPE, or Resin having flexibility after solidification of urethane-based TPE or the like is used.

  In the molding process having the extrusion molding machine 9 corresponding to the mold extrusion molding machine, the resin material 7 is put into the cylinder 10 from the hopper 8 of the extrusion molding machine 9. The resin material 7 put into the cylinder 10 is heated, melted and stirred at a constant temperature by the cylinder 10 and is extruded by the screw 11 in the direction of the extrusion head 12 attached to the tip of the cylinder 10. A head die 13 is attached to the extrusion head 12. The resin discharge port side of the head die 13 is formed into an opening having a hollow cross-sectional shape, and the resin extruded from the head die 13 is formed into a hollow small-diameter tube A.

In the cooling process for cooling the extruded resin, the tube A molded by the extrusion molding machine 9 is cooled to near room temperature by the cooler 14 having the cooling tank 15 containing water. The cooled tube A is taken out of the cooler 14 with a predetermined tension by the take-up machine in the take-up process. After passing through the cooler 14, the moisture attached to the tube A is scattered by the gas blow 59. In place of the gas blow 59, moisture may be wiped off with a moisture wiping cloth sponge or the like.
The tube A is used, for example, for water supply piping instead of a conventional PVC pipe, and is rich in elasticity, flexibility, and airtightness. The appearance of the tube A is inspected by the inspection device 20.

As shown in FIGS. 2A and 2B, the inspection apparatus 20 fixes the bent piece 1c of the L-shaped support frame 1b to the surface of the floor installation board 1a, and the vertical rising piece of the support frame 1b. On both sides of 1d, there are support members 30 on which vertical pieces 1e, 1e are fixed by upper and lower bridges 1f, 1f. A guide cylinder 32 having a tube guide hole 31 is supported on the upper ends of the vertical pieces 1e and 1e of the support member 30. The outer peripheral side of the guide tube 32 is fixed to the inner peripheral side of the disk 34 with a plurality of support pieces 33.
The lower part of the outer periphery of the disk 34 is screwed to the upper ends of the two vertical pieces 1e, 1e, and the disk 34 faces the direction perpendicular to the moving direction of the tube A and is supported on the center side of the disk 34. The central axis of the guide cylinder 32 coincides with the extrusion extension direction P of the tube A.
In this case, a plurality of CCD cameras (in this example, six CCD cameras 35 to 40) are maintained on the outer peripheral side of the disc 34 positioned on the discharge side of the tube A of the disc 34, with an angle of 60 degrees. Is fixed. In the present embodiment, six CCD cameras 35 to 40 are used. However, a plurality of CCD cameras may be used, but at least two, preferably five or more CCD cameras may be used. For example, when imaging with two cameras, the angle captured by one CCD camera is 180 degrees, and there is no overlap in the field of view captured by each other, so images acquired near the boundary of the field of view are not reliable. In some cases, an area that is not imaged is created. In addition, when three or four CCD cameras are used, the images can be overlapped with each other, so that it is possible to capture images reliably over the entire circumference. However, the curvature of the tube A is harder than the CCD camera. However, it is not certain in the detection of scratches. Therefore, by using at least five or more CCD cameras and narrowing the imaging range of each CCD camera as much as possible, it becomes possible to reliably detect a scratch. The CCD cameras 35 to 40 are constituted by, for example, line cameras, and are arranged along the circumferential direction so that a range where each image is captured has an overlapping portion in the circumferential direction on the outer circumferential surface of the tube A. Further, the CCD cameras 35 to 40 are configured to take an image at an angle α inclined (inclined in the moving direction of the tube A) from the perpendicular component F to the exit direction of the guide tube 32 with respect to the extending direction of the tube A. .
The six CCD cameras 35 to 40 are supported by a slider 42 by a band 41, and a driving body 43 that moves and adjusts the slider 42 inward and outward is fixed to the support body 44 in the above-described tilted state together with the slider 42. The The support body 44 protrudes from the outer periphery of the disk 34.
The slider 42 and the driving body 43 are configured such that the driving body 43 is configured by a gear motor, and the slider 42 moves inward and outward on the disk 34 along the support body 44 via the gear. The slider 42 and the driving body 43 may be configured by a cylinder mechanism.
Both the slider 42 and the driving body 43 constitute positioning means 60 for positioning the six CCD cameras 35 to 40 with respect to the outer peripheral surface of the tube A. The CCD cameras 35 to 40 are cross-sectional shapes of the tube A (quadrangular, elliptical). Each of them is positioned at a predetermined position in synchronism with the outer periphery of the shape, circle, etc.

  As shown in FIG. 3, a ring-shaped illuminator 45 is attached to the tip of the guide tube 32 to irradiate the discharge side outer peripheral surface of the tube A in a ring shape (see FIG. 2A). The entire surface of the tube A irradiated by the ring-shaped illuminator 45 is imaged by the six CCD cameras 35 to 40 at 360 degrees. As an example, the ring-shaped illuminator 45 is configured to irradiate the entire circumferential direction along the extending direction of the tube A by arranging a light source such as an LED and an optical fiber that guides light from the light source in a ring shape. Therefore, when there are irregularities due to scratches on the outer peripheral surface of the tube A, the light irradiated along the extending direction of the tube A is blocked by the concave portion or the convex portion, and a shadow is generated. Unevenness on the surface of the tube A is detected with high accuracy when the irradiated region is imaged. The ring-shaped illuminator 45 is movable along the extending direction of the tube A so as to be optimal with respect to the imaging position of the CCD cameras 35 to 40 as the CCD cameras 35 to 40 move. It is attached to the tip of 32.

In FIG. 4, reference numeral 50 denotes a camera control device that controls six CCD cameras 35 to 40. In FIG. 4, reference numeral 51 denotes an image of the six CCD cameras 35 to 40 corresponding to the transport speed signal of the tube A. An imaging cycle control means for controlling the cycle, 52 is a speed sensor that detects the conveying speed of the tube A and outputs a signal to the imaging cycle control means 51, and 53 synthesizes images taken by the six CCD cameras 35 to 40. An image processing means 54 is a computing means for optimizing images taken by the six CCD cameras 35 to 40, and 55 is a storage means for automatically accumulating the taken images.
If the conveyance speed of the tube A is increased by the imaging cycle control means 51, the cycle of capturing an image is shortened, and if the conveyance speed of the tube A is decreased, the cycle of capturing an image is increased, thereby extending the entire length of the tube A. Control to prevent missing images. That is, control is performed so that the imaging period of the CCD cameras 35 to 40 constituted by line cameras and the transport speed of the tube A are synchronized and the surface of the tube A is continuously imaged. Although the CCD cameras 35 to 40 are constituted by line cameras, the front frame is obtained by taking an image with an area camera so that the rear edge of the previous frame of the captured image overlaps the front edge of the next frame after imaging. In addition, the tube A may be controlled so as not to be leaked between the rear frames, and the tube A may be continuously imaged over the entire length. Therefore, captured images continuously captured by the CCD cameras 35 to 40 are output to the image processing unit 53 and subjected to image processing.
The image processing means 53 combines the images K1 to K6 picked up by the six CCD cameras 35 to 40 and outputs them as a combined image F1, and sequentially outputs the combined images F2, F3, ..., Fn-1, Fn. In this way, the appearance of the surface of the tube A is obtained by continuously synthesizing. The images K <b> 1 to K <b> 6 have overlapping portions that overlap each other in the circumferential direction, but are synthesized as one synthesized image by the image processing unit 53.
56 is a switch, 57 is a power source, and 58 is an alarm. The speed sensor 52 is constituted by a tachometer or an encoder that detects the number of rotations per unit time of the rotating body provided in the take-up machine.

With the above configuration, in FIG. 1, the tube A as the object to be inspected is extruded based on the operation of the extrusion molding machine, cooled by the cooling machine 14, and taken up by the take-up machine. As shown in (b), it is guided through the tube guide hole 31 of the guide cylinder 32.
In this case, the switch 56 is turned on, the ring-shaped illuminator 45 is turned on, and the CCD cameras 35 to 40 operate at a cycle corresponding to the speed of the tube A by the imaging cycle control means 51 of the camera control device 50 shown in FIG. . That is, in accordance with the speed of the tube A, the entire circumference of the surface of the tube A is continuously imaged by the six CCD cameras 35 to 40, and the images K1 to K6 of the surface of the tube A that are output are output by the image processing means 53. By combining the composite image as a composite image and pattern matching the composite image with the normal reference pattern image stored in advance in the storage unit 55 based on the shape of the captured image and the luminance value, the presence or absence of unevenness Is detected, that is, if the composite image matches the reference pattern image, no alarm signal is output to the alarm 58 and no alarm is issued.

On the other hand, as shown in FIG. 5, when the tube A in which the concave portion T is formed in the extending direction passes through the imaging positions of the six CCD cameras 35 to 40, the concave portion T is formed by any one of the CCD cameras 35 to 40. Is imaged. The composite image obtained by capturing the image of the concave portion T is subjected to pattern matching with the reference pattern by the calculation means 54, and a difference in luminance of the concave portion T is detected and an alarm is issued from the alarm 58. Based on the alarm, the storage means 55 stores the length position in the extending direction of the tube A as flaw information together with the captured image.
According to the present invention, since each CCD camera 35 to 40 is positioned so as to surround the object to be inspected constituted by the tube A, the entire outer periphery can be observed, and no inspection omission occurs.
It is also possible to know how the tube A is deformed by comparing the captured images captured by the CCD cameras 35 to 40 with the reference pattern. Moreover, since the images K1 to K6 can be continuously detected over the entire length of the tube A by controlling the imaging cycle, no detection omission occurs. Further, since the inspection of the image is performed in a dry state in which moisture is blown off by the blow of the gas blow 59, a high-precision appearance inspection can be performed without causing an error due to moisture adhesion.
Further, since the camera is inclined at an angle α to the exit direction of the guide tube 32 from the right angle component F and the cameras 35 to 40 with respect to the direction of the tube A, a three-dimensional effect can be given to the captured image, and the uneven portion of the tube A Can also be detected, and pass / fail judgment can be made accurately.

For example, when the cross-sectional shape of the object to be inspected is an ellipse or a polygon such as a triangle or a quadrangle, the positioning unit 60 sets the camera position to a preferable position with respect to the outer periphery of the object to be inspected. Appearance inspection corresponding to the product type is possible.
Further, the object to be inspected is not limited to a tube, and may be another long material such as a conductive material coated with a coating machine, an element wire, a tire cord, a fiber material, or a carbon material.
Further, the object to be inspected is a long material, and may be a fixed size made of a slightly soft material.
Also, a configuration may be adopted in which a stereoscopic image is formed by image processing based on the images K1 to K6 and this is determined.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. Various modifications or improvements can be added to the above embodiment.

9 Extruder, 14 Cooler, 20 Inspection device, 30 Support member,
31 Tube guide hole, 32 guide tube, 33 support piece, 34 disc,
35 to 40 CCD camera, 41 band, 42 slider, 43 driver,
44 support body, 45 ring-shaped illuminator, 46 light source, 47 optical fiber,
48 light output end, 50 control device, 51 imaging cycle control means, 52 speed sensor,
53 image processing means, 54 computing means, 55 storage means, 56 switches,
57 power supply, 58 alarm, 59 gas blow, 60 positioning means.

Claims (6)

An appearance inspection device for a long object to be inspected using a resin material that moves in an extending direction as a raw material ,
A guide tube whose center axis coincides with the extension direction of the inspection object;
Five or more cameras that are arranged so as to surround the object to be inspected from the outside and that image the object to be inspected guided by the guide cylinder ;
An annular illuminator that is provided at a tip of the guide tube on the camera side and that irradiates an imaging position of the inspection object by the camera along an outer peripheral surface of the inspection object;
An appearance inspection apparatus comprising: an image processing unit that processes an appearance image of the inspection target object obtained by imaging the inspection target object in the extension direction by the five or more cameras. The appearance inspection apparatus according to claim 1, wherein the image processing unit sequentially synthesizes the appearance images captured at a predetermined imaging cycle by the five or more cameras. Imaging direction of the camera, the appearance inspection apparatus according to claim 1 or claim 2, characterized in that it is disposed inclined from a direction perpendicular to the extending direction of the object to be inspected.   The appearance inspection apparatus according to any one of claims 1 to 3, wherein the appearance inspection apparatus includes positioning means for positioning a position of the camera with respect to the object to be inspected. The said appearance inspection apparatus is provided with the imaging period control means which controls the imaging period of the said 5 or more cameras according to the moving speed of the said to-be-inspected target object. Appearance inspection apparatus as described.   6. The appearance inspection apparatus according to claim 1, further comprising a moisture removing member that removes moisture attached to the object to be inspected before imaging the object to be inspected by a camera. .

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