JP2017067622A - Article inspection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an article inspection device capable of accurately inspecting an entire seal area of an object under inspection.SOLUTION: A light-emitting region E of a light source unit 3 is divided into a region E1 and regions E2 in a conveying direction A, where light with a center wavelength λ1 is emitted from the region E1 and light with a center wavelength λ2 is emitted from the regions E2. A line sensor 4 receives light with center wavelengths λ1, λ2 emitted from the light source unit 3 and transmitted through an object under inspection W, and generates a detection signal that is based on volumes of split transmission rays with center wavelengths λ1, λ2. Linear light source images and surface light source images are separately generated from detection information that is based on transmission light volumes represented by the detection signal from the line sensor 4 to obtain two kinds of transmission images, which are used to identify a seal area of a seal section Wc of the object under inspection W and determine the presence or absence of anomaly in the seal area.SELECTED DRAWING: Figure 2

Description

  The present invention relates to an abnormality in the seal area of an object to be inspected in which the contents are wrapped in a translucent packaging material (for example, the contents, the contents are debris, the foreign matter is bitten, the seal is poor (adhesion failure due to wrinkles) And the like).

  For example, in the case of a product in which contents are stored in a bag-shaped packaging material, the opening portion is sealed after the contents are stored in the packaging material. At this time, the contents, the contents of the contents, or foreign matter may be caught in the seal area of the packaging material, and this defective seal product needs to be excluded as a defective product.

  In particular, as a seal part defect detection device for inspecting the presence or absence of a seal failure of a test object by using a product in which the contents are wrapped in a translucent packaging material and sealed. For example, what is disclosed in Patent Document 1 below is known.

  The seal portion defect detection device disclosed in Patent Document 1 includes a light projecting unit and a plurality of light intensity detection units, and uses a difference image based on outputs from the two light intensity detection units.

  More specifically, as shown in FIG. 5, the seal portion defect detection device 51 disclosed in Patent Document 1 includes a light projecting means 52, a plurality of light intensity detecting means 53 (53a, 53b), a reference value setting means 54, Difference detection means 55 and comparison determination means 56 are provided. The light projecting means 52 projects light onto the seal portion 28 of the package 57. The plurality of light intensity detecting means 53 (53a, 53b) are provided at positions facing the light projecting means 52 with the seal portion 58 of the package 57 therebetween. The light intensity detecting means 53 (53a, 53b) detects light transmitted through the seal portion 58 of the package 57 by the projection of light from the light projecting means 52. The reference value setting means 54 sets in advance a reference value for determining whether or not the contents are caught in the seal portion 58 of the package 57. The difference detection means 55 calculates the difference in output from two of the plurality of light intensity detection means 53a and 53b. The comparison determination unit 56 includes an integration circuit 56a and a comparator 56b, integrates the output from the difference detection unit 55 by the integration circuit 56a, and compares this integration output with the reference value from the reference value setting unit 54. If the integrated output is larger than the reference value from the reference value setting means 54, it is determined that the contents are caught in the seal portion 58 of the package 57.

  As described above, in the seal portion defect detection device 51 disclosed in Patent Document 1 described above, the difference detection unit 55 calculates the difference between the outputs from two of the plurality of light intensity detection units 53a and 53b, and performs comparison and determination. The means 56 compares the reference value from the reference value setting means 54 with the output from the difference detection means 55, and determines whether or not the contents are caught in the seal portion 58 of the package 57 based on the comparison result. Yes.

JP 7-146251 A

  However, the seal portion defect detection device 51 disclosed in Patent Document 1 described above has a plurality of light intensity detection units 53a and 53b at a specific height (position) in a direction parallel to the conveyance direction of the package 57. In this configuration, the presence / absence of biting of the contents in the seal portion 58 is determined based on a comparison between the difference between the two outputs and the reference value. It was not possible to inspect the presence of biting of the contents in the entire seal area by specifying the seal area.

  Therefore, the inventors of the present invention use an imaging technique using a light source and a line sensor in order to specify the seal area of the above-described seal portion of the object to be conveyed W and to check whether or not the contents are bitten in the entire seal area. The test of bite inspection was attempted using two types of light sources, a surface light source and a line light source, having different light emission areas with respect to the inspection object W (conveying surface on which the inspection object W is conveyed). An example of the transmission image obtained by this experiment is shown in FIGS. The surface light source irradiates the inspection object W with planar light, and the line light source irradiates the inspection object W with linear light having a light emission area smaller than that of the surface light source. FIG. 6A is a transmission image when the light source is a surface light source, and FIG. 6B is a transmission image when the light source is a linear ray. When the light source is a surface light source, as shown in FIG. 6 (a), the contents Wb of the object W to be inspected and the foreign matter Wd caught in the seal area of the seal portion Wc are clearly visible, but the packaging material Wa It has been found that the boundary We of the seal portion Wc is difficult to understand. On the other hand, when the light source is a line light source, as shown in FIG. 6B, the seal portion Wc of the object W can be clearly seen and the boundary We of the seal region can be clearly distinguished, whereas the seal portion It was found that the foreign matter Wd caught in the Wc seal region and the line-shaped noise X are difficult to distinguish.

  By the way, the above-described imaging technique can be employed when inspecting a transport line while transporting an object to be inspected with a seal portion in a direction perpendicular to the transport direction. In that case, generally, the surface light diffused to the object to be inspected is irradiated to reduce the influence of the unevenness of the seal portion for improving the sealing property, thereby improving the accuracy of foreign object detection. However, as can be seen from the experimental results showing the characteristics of the surface light source described above, the boundary of the seal portion is difficult to understand and the seal region cannot be specified. On the other hand, when a line light source is used so that the seal area of the object to be inspected can be identified, the detection accuracy of the abnormality in the seal area is lowered this time, as can be seen from the experimental results showing the characteristics of the line light source. Arise.

  For this reason, in inspecting the entire seal area of the inspection object with high accuracy, it is possible to use both the surface light source and the line light source and take advantage of the features of both of the above, but each of the surface light source and the line light source A plurality of line sensors for receiving the light from the light source are also required, and there are problems in terms of the captain (device size) and cost.

  Therefore, the present invention has been made in view of the above problems, and provides an article inspection apparatus that can solve the problem of the length and cost and can inspect the entire seal area of the inspection object with high accuracy. The purpose is that.

In order to achieve the above object, an article inspection apparatus according to claim 1 of the present invention transports an inspection object W in which a content Wb is wrapped in a packaging material Wa and irradiates the inspection object with light. , An article inspection apparatus 1 that performs an inspection in a sealing region of the packaging material based on a transmission image obtained by detecting the transmitted light,
A line sensor 4 in which a plurality of elements for detecting the transmitted light are arranged in a direction intersecting a transport direction A of the inspection object;
A surface that traverses each element of the line sensor and that is perpendicular to the transport surface 2c on which the object to be inspected is transported is defined as a reference surface L, and first from a plurality of angles centered on the reference surface. A light source unit 3 that emits second light from a direction along the reference plane that includes at least a wavelength λ1 different from the wavelength λ2 of the first light,
A processing unit 7 that specifies the seal region based on a detection signal obtained from the line sensor according to light of each wavelength irradiated by the light source unit, and determines whether there is an abnormality in the seal region. It is characterized by that.

The article inspection apparatus according to claim 2 is the article inspection apparatus according to claim 1,
The processing unit 7 is characterized in that the seal region is specified from a detection signal when the line sensor 4 receives light having a wavelength λ1 of light of the reference plane L.

The article inspection apparatus according to claim 3 is the article inspection apparatus according to claim 1 or 2,
The line sensor 4 includes a plurality of cameras 11 and 12 having sensitivities corresponding to the wavelengths λ1 and λ2 of the plurality of lights emitted from the light source unit 3, respectively.

The article inspection apparatus according to claim 4 is the article inspection apparatus according to claim 1 or 2,
The line sensor 4 includes a single camera 13 having a spectral function.

The article inspection apparatus according to claim 5 is the article inspection apparatus according to claim 1 or 2,
The line sensor 4 is provided in front of any of the plurality of cameras 14 and 15 having sensitivity to the wavelengths of the plurality of lights emitted from the light source unit 3 and the light of the reference plane L. And a filter 16 that allows the light on the reference surface to pass through in correspondence with the wavelength λ1.

  According to the article inspection apparatus according to the present invention, light along a reference surface and light from a plurality of angles centered on the reference surface are irradiated from the light source unit, and among the light irradiated from the light source unit, the reference surface The light along the surface is scattered by the unevenness of the seal area of the seal part of the inspection object, and the amount of light transmitted is reduced, so that light having a wavelength included only in the light along the reference plane is detected. The seal area of the seal portion is specified. In addition, the light emitted from the entire light emitting region of the light source unit reduces the influence of the unevenness of the seal region of the seal portion, and is received only when there is a foreign object in the seal region of the seal portion, and the light received by the element of the line sensor Using the decrease in the amount, the light in the entire light emitting region of the light source unit is detected to detect an abnormality in the seal region of the seal unit. With such a configuration, it is not necessary to prepare a line light source and a surface light source separately to prepare two types of light source sections, shorten the length of the apparatus, avoid an increase in the size of the apparatus, and reduce the cost. The entire seal area can be inspected with high accuracy.

It is a block diagram which shows schematic structure of the article inspection apparatus which concerns on this invention. It is a schematic explanatory drawing in the case of inspecting an inspected object using two wavelengths λ1 and λ2 in the light source part of the article inspection apparatus according to the present invention. (A) An example of a line sensor in an article inspection apparatus according to the present invention, in which a camera having sensitivity to light having a central wavelength λ1 and a camera having sensitivity to light having a central wavelength λ2 are used as line sensors. FIG. (B) It is a figure which shows the intensity | strength of the light of two cameras in (a). (A) It is another example of the line sensor in the article inspection apparatus according to the present invention, and is a schematic explanatory diagram when a line sensor with a spectral function is used as a line sensor. (B) Another example of the line sensor in the article inspection apparatus according to the present invention, in which one of the two cameras having sensitivity to the light having the center wavelengths λ1 and λ2 has the wavelength of the center wavelength λ1. It is a schematic explanatory drawing at the time of using the line sensor provided with the filter which lets only light pass. It is a block diagram which shows one structural example of the seal | sticker part defect detection apparatus disclosed by patent document 1 as a prior art. (A) It is a figure which shows an example of the picked-up image when a linear light source is used as a light source part. (B) It is a figure which shows an example of the picked-up image when a surface light source is used as a light source part.

  The article inspection apparatus according to the present invention is incorporated in a part of a conveyance line or a packaging apparatus, and irradiates light while conveying an object (article) whose contents are wrapped in a packaging material, and detects the transmitted light. Based on the transmission image obtained in this way, the presence or absence of abnormalities in the seal area of the packaging material (for example, contents, content debris, foreign matter biting, seal failure (adhesion failure or breakage due to wrinkles), etc.) is inspected. To do.

  As shown in FIG. 1, the article inspection apparatus 1 includes a transport unit 2, a light source unit 3, a line sensor 4, an operation unit 5, a drive control unit 6, a processing unit 7, and a display unit 8.

  The conveyance unit 2 is configured by, for example, a belt conveyor, and the introduction-side conveyor 2a and the discharge-side conveyor 2b are arranged on the conveyance line with a predetermined gap S therebetween. The conveyance unit 2 introduces and conveys the inspection object W to be inspected by the introduction side conveyor 2a, and discharges and conveys the inspection object W after the inspection by the discharge side conveyor 2b.

  As shown in FIG. 2, the inspection object W to be inspected contains the contents Wb in a packaging material Wa having translucency through which light emitted from the light source unit 3 can pass. The inspected object W seals the inner part by a predetermined width from the opposite ends of the packaging material Wa, and the area from the both ends of the packaging material Wa to the sealing part is used as a sealing area of the seal portion Wc. As shown in FIG. 1, the inspection object W is transported by the transport unit 2 in a state where both sides of the packaging material Wa are sealed in the direction perpendicular to the transport direction A (the depth direction on the paper surface).

  Note that the inspection object W to be inspected may be a so-called continuous package in which a plurality of packaging materials Wa containing the contents Wb are continuously arranged via the seal portion Wc.

  As shown in FIG. 1, the light source unit 3 is provided above the transport unit 2 so as to face the line sensor 4 through the gap S, and has a predetermined wavelength toward the inspection object W transported by the transport unit 2. (Light having a center wavelength λ1, light having a center wavelength λ2, and light including center wavelengths λ1 and λ2 described later).

  The light source unit 3 has a surface in the direction perpendicular to the conveyance surface 2c on which the inspection object W passing through a line traversing each element (all elements) in the longitudinal (element arrangement) direction of the line sensor 4 is defined as a reference plane L. (The surface indicated by the dotted line in FIG. 2), the light at a different angle (incident angle θ with respect to the transport surface 2c in FIG. 1) around the reference plane L and the wavelength of this light (λ2 in this example) are different. Light is irradiated along the reference plane L including the wavelength (λ1 in this example).

  As shown in FIG. 2, the light source unit 3 irradiates light toward the inspection object W with the following irradiation pattern (irradiation pattern 1 or irradiation pattern 2).

  As shown in FIGS. 3A and 3B, the light source unit 3 of the irradiation pattern 1 has a central portion of the light emitting region E as a region E1 that emits light having a central wavelength λ1, and both sides of the region E1 have a central wavelength. The region E2 emits light having a center wavelength λ2 in a wavelength band that does not overlap with the wavelength band of λ1. The light having the center wavelength λ1 from only the region E1 functions as a line light source having a predetermined incident angle range centered on the reference plane L1 that can specify the seal region of the seal portion Wc of the inspection object W. Further, the light having the center wavelengths λ1 and λ2 from both the regions E1 and E2 of the entire light emitting region E is a surface having a predetermined incident angle range for determining an abnormality in the seal region of the seal portion Wc of the inspection object W. Functions as a light source.

  Note that the surface light source and the line light described above have different light emission areas of light emitted toward the inspection object W, and the line light source emits linear light having a light emission area smaller than that of the surface light source. The light transmitted through W reaches the light receiving surface 4 a of the line sensor 4. Moreover, the light source part 3 may comprise the part (the whole or part of the area | region E2) which functions as a surface light source mentioned above with a some line light source. In that case, an arbitrary number of line light sources can be provided at arbitrary positions within the range of the region E2 according to the inspection conditions. Furthermore, the length in the width direction orthogonal to the transport direction A of the light emitting region E in the light source unit 3 may be at least equal to or greater than the detection region of the inspection object W.

  In addition, the light source unit 3 is provided with an optical filter at each of the emission port of the region E1 and the emission port of the region E2 in the light emission region E, emits light with the central wavelength λ1 from the region E1, and emits light with the central wavelength λ2 from the region E2. It can also be configured by appropriately selecting the pass wavelength of the optical filter so as to emit light.

  On the other hand, the light source unit 3 of the irradiation pattern 2 emits white light including the center wavelengths λ1 and λ2 from the entire region (region E1 and region E2) of the light emitting region E, and passes only the center wavelength λ2 to the exit of the region E2. An optical filter is provided to irradiate white light including the center wavelengths λ1 and λ2 from the region E1 of the light emitting region E, and irradiate light having only the center wavelength λ2 through the optical filter from the region E2.

  In addition, when irradiating the light of the irradiation pattern 1 or the irradiation pattern 2 described above, the light source unit 3 appropriately sets the wavelength of light emitted from the regions E1 and E2 of the light emitting region E without using an optical filter. It can also be configured.

  As shown in FIG. 1, the line sensor 4 is provided below the transport unit 2 so as to face the light source unit 3 with a gap S therebetween. The line sensor 4 includes a plurality of elements including, for example, a condensing lens and a photodiode (phototransistor), and is orthogonal to the direction in which the inspection object W is conveyed (arrow A in FIG. 1) (conveyed by the conveying unit 2). A plurality of elements are arranged in a line at a predetermined pitch in a plane (reference plane L) direction orthogonal to the plane 2c.

  The line sensor 4 detects light from the light source unit 3, and for example, the configuration shown in FIG. 3A, FIG. 4A, or FIG.

  The line sensor 4A in FIG. 3A is configured by arranging a first camera 11 and a second camera 12 side by side in the transport direction A. The first camera 11 has sensitivity corresponding to the light with the center wavelength λ1 in the light emitted from the light source unit 3, and the second camera 12 has the center wavelength λ1 and the center in the light emitted from the light source unit 3. Sensitivity corresponding to light of wavelength λ2. As a result, when light of the central wavelength λ1 and light of the central wavelength λ2 are irradiated from the light source unit 3 onto the inspection object W, the light of the central wavelength λ1 passing through the inspection object W is transmitted to the first camera 11. The second camera 12 receives the light, and the second camera 12 receives the light having the center wavelength λ2 that passes through the inspection object W. Then, the first camera 11 outputs a detection signal based on the amount of transmitted light having the received center wavelength λ1 to the processing unit 7. Further, the second camera 12 outputs a detection signal based on the amount of transmitted light of the received center wavelength λ1 and center wavelength λ2 to the processing unit 7.

  The line sensor 4B in FIG. 4A is configured by a single third camera 13 having a spectral function. As a result, when the light with the central wavelengths λ1 and λ2 is irradiated from the light source unit 3 onto the inspection object W, the light with the central wavelengths λ1 and λ2 passing through the inspection object W is reflected by the camera 4C having a spectroscopic function. The light is split into light having a central wavelength λ1 and light having a central wavelength λ2. Then, a detection signal based on the transmitted light amount of the center wavelength λ1 and a detection signal based on the transmitted light amount of the center wavelength λ2 are output to the processing unit 7.

  The line sensor 4C in FIG. 4B has a fourth camera 14 and a fifth camera 15 arranged side by side in the transport direction A, and one camera (the fifth camera 15 in the example of FIG. 4B). ) Is provided in front of the light receiving surface. The fourth camera 14 and the fifth camera 15 have sensitivities corresponding to both the light with the central wavelength λ1 and the light with the central wavelength λ2 irradiated by the light source unit 3. In addition, the filter 16 has a characteristic of allowing only light having the center wavelength λ1 to pass through the light emitted from the light source unit 3. As a result, when light of the center wavelengths λ1 and λ2 is irradiated from the light source unit 3 onto the inspection object W, the fourth camera 14 receives the light of the center wavelengths λ1 and λ2 passing through the inspection object W. Of the light having the center wavelengths λ1 and λ2 passing through the inspection object W, only the light having the center wavelength λ1 passes through the filter 16 and is received by the fifth camera 15. Then, the fourth camera 14 outputs a detection signal based on the amount of transmitted light having the received center wavelengths λ 1 and λ 2 to the processing unit 7. In addition, the fifth camera 15 outputs a detection signal based on the transmission amount of the light having the center wavelength λ 1 received through the filter 16 to the processing unit 7.

  Note that the second camera 12 of the line sensor 4A in FIG. 3A and the fourth camera 14 of the line sensor 4C in FIG. It has a sensitivity corresponding to the center wavelength λ <b> 2 of the light emitted by the light source unit 3, and outputs a detection signal based on the amount of transmitted light having the received center wavelength λ <b> 2 to the processing unit 7.

  In this example, the configuration in which light having the central wavelength λ1 is emitted from the region E1 of the light emitting region E in the light source unit 3 and light having the central wavelength λ2 is emitted from the region E2 is mainly described. Is not to be done. That is, the light source unit 3 only has to irradiate a plurality of lights having different angles around the reference plane L and light along the reference plane L including a wavelength different from the wavelength of the light, and a part of the wavelength range is limited. It may be duplicated. At that time, the line sensor 4 separates the light passing through the reference surface L and the light at other angles by the difference in the wavelength, with the light from the light source unit 3 irradiating the inspection object W and passing therethrough. It is only necessary to have a function that can be detected. For example, it is configured to irradiate light having wavelengths λ1 and λ2 along the reference plane L and light having a wavelength of only λ2 at other angles, and the line sensor 4 emits light of λ1 and λ2. Separate and detect. Further, as in the irradiation pattern 2, an optical filter is provided to allow light from a light source that irradiates white light (including λ 1 and λ 2) to pass only the wavelength λ 2 at the exit port of the region E 2 of the wavelength region E. The inspection object W can be configured to irradiate light having a desired wavelength, and the line sensor 4 can detect the light having wavelengths λ1 and λ2 separately.

  The arrangement direction of the plurality of elements constituting the line sensor 4 is not limited to the direction orthogonal to the conveyance direction A of the inspection object W, but the incident angle of the light emitted from the light source unit 3, the inspection target It can be set as appropriate according to the type of the item W.

  The operation unit 5 includes, for example, a plurality of keys and switches operated by the user, soft keys on the display screen of the display unit 9, and the like. The operation unit 5 instructs to start or stop the operation of the article inspection apparatus 1, sets the type and number of inspections of the inspection object W, sets the conveyance speed of the conveyance unit 2, and starts the drive control unit 6 and the processing unit 7. It is operated when performing etc.

  The drive control unit 6 performs on / off control of the light source unit 3 so as to irradiate the inspection target W with light having a desired wavelength according to the irradiation pattern of the light source unit 3.

  The drive control unit 6 may control the line sensor 4 at a detection timing synchronized with the irradiation timing of the light source unit 3. In that case, the drive control unit 6 receives the light passing through the inspection object W at the detection timing synchronized with the irradiation timing at which the regions E1 and E2 of the light emitting region E in the light source unit 3 are turned on. To control.

  The processing unit 7 acquires two types of transmission images based on the detection signal from the line sensor 4, specifies the seal region of the seal portion Wc in the inspection object W, determines whether there is an abnormality in the seal region, and displays the inspection result. The storage unit 7a, the image acquisition unit 7b, the seal area specifying unit 7c, the abnormality determination unit 7d, and the display control unit 7e are provided.

  The storage unit 7a sequentially stores detection information based on the detection signal from the line sensor 4. That is, the storage unit 7a uses the amount of received light when receiving light with the center wavelength λ1 emitted from the light source unit 3 as the line light source detection information of the line sensor 4, and uses the center wavelengths λ1 and λ2 emitted from the light source unit 3. The amount of light received when the line sensor 4 receives light is sequentially stored as surface light source detection information of the line sensor 4.

  The image acquisition unit 7b separately acquires two types of transmission images from the detection information (line light source detection information and surface light source detection information) of the line sensor 4 stored in the storage unit 7a. The two types of transmission images are a line light source image for specifying the seal area of the seal portion Wc in the inspection object W, and an abnormality (content Wb, content Wb in the seal area of the seal portion Wc in the inspection object W. It is a surface light source image for determining the presence or absence of defects such as fogging, foreign object biting, and sealing failure due to wrinkling. The image acquisition unit 7b acquires the line light source image by reading the line light source detection information stored in the storage unit 7a and imaging it. Moreover, the image acquisition part 7b acquires a surface light source image by reading the surface light source detection information memorize | stored in the memory | storage part 7a, and imaging it.

  The seal area specifying unit 7c specifies the seal area of the seal part Wc in the inspection object W from the line light source image acquired by the image acquisition unit 7b. Specifically, the gray value (luminance) of each pixel of the line light source image acquired by the image acquisition unit 7b (an image in which the horizontal direction is the transport direction and the vertical axis is the direction perpendicular to the transport direction and parallel to the transport surface 2c). (Value) is binarized, the contour and boundary line of the inspection object W are obtained, and the region from the contour to the boundary line is specified as the seal region of the seal portion Wc. For example, when the seal area is at both ends in the horizontal direction, the vertical lines drawn inward from the innermost vertical line by a predetermined distance (boundary adjustment value) among the vertical lines appearing in the contour are obtained as boundary lines. To identify the seal area.

  The abnormality determination unit 7d detects an abnormal portion from the surface light source image acquired by the image acquisition unit 7b, and determines whether or not the detected abnormal portion exists in the seal region of the seal portion Wc of the inspection object W. The presence or absence of abnormality is determined. Specifically, the gray value (luminance value) of each pixel of the surface light source image acquired by the image acquisition unit 7b is binarized, and the area of the pixel “1” is detected as an abnormal portion, and the line light source image is detected. In the superimposed image obtained by superimposing the image in which the seal area is specified and the surface light source image, an abnormality in the seal area is determined based on whether or not the abnormal part exists in the seal area specified by the seal area specifying unit 7c. The presence or absence of is determined.

  Note that when the abnormality determination unit 7d determines whether there is an abnormality in the seal area of the seal portion Wc in the inspection object W, the threshold value, boundary adjustment value, and seal portion Wc for specifying the seal area of the seal portion Wc are determined. In order to determine whether or not there is an abnormality in the seal region, a determination reference value corresponding to the abnormality content can be set in advance and stored in the storage unit 7a. In this case, the seal area specifying unit 7c compares the gray value (luminance value) of each pixel of the line light source image acquired by the image acquisition unit 7b with a threshold value, and the contour of the inspection object W from the image of the pixel exceeding the threshold value. The vertical line appearing in the contour is extracted, the inner side of the innermost vertical line is obtained as the boundary line by the boundary adjustment value, and the region from the contour to the boundary line is specified as the seal region of the seal portion Wc. Then, the abnormality determination unit 7d sets a determination reference value in the seal area specified by the seal area specifying unit 7c in the superimposed image obtained by superimposing the line light source image and the surface light source image acquired by the image acquisition unit 7b. Whether or not there is an abnormality in the seal region is determined based on whether or not there are more pixels. The boundary adjustment value may be calculated by a statistical method (average, maximum value, median value, etc.) from the interval between vertical lines appearing in the contour.

  The display control unit 7e includes, for example, two types of transmission images (line light source image and surface light source image) of the inspection object W acquired by the image acquisition unit 7b, the inspection result of the inspection object W based on the determination of the abnormality determination unit 7d, The display of the display unit 9 is controlled so as to display various information such as the total number of inspections, the number of non-defective products, and the total number of NG.

  The display unit 9 is composed of a display device such as a liquid crystal display, for example, and displays various types of information including the inspection result of the inspection object W under the control of the display control unit 7e.

  Next, in the article inspection apparatus 1 configured as described above, an operation in the case where the light of the irradiation pattern 1 is irradiated from the light source unit 3 to inspect the seal portion Wc of the inspection object W will be described.

  When the inspection object W to be inspected is introduced and conveyed by the introduction-side conveyor 2a of the conveyance section 2, the inspection object W is irradiated with light having the center wavelength λ1 from the light emission area E1 of the light source section 3. At the same time, the region E2 is irradiated with light having the center wavelength λ2.

  The line sensor 4 receives the light passing through the inspection object W when the light of the center wavelength λ1 and the light of the center wavelength λ2 are irradiated from the light source unit 3 to the inspection object W, and receives the received light. Is split into light having the center wavelengths λ 1 and λ 2, and a detection signal based on the amount of transmitted light of each of the split center wavelengths λ 1 and λ 2 is output to the processing unit 7.

  Here, in the case where the line sensor 4 has the configuration of FIG. 3A, the light having the center wavelengths λ <b> 1 and λ <b> 2 is irradiated from the light source unit 3 to the inspection object W and passes through the inspection object W. The first camera 11 and the second camera 12 receive the light having the center wavelength λ1, and the second camera 12 receives the light having the center wavelength λ2 that passes through the inspection object W. Then, the first camera 11 outputs a detection signal based on the amount of transmitted light having the received center wavelength λ1 to the processing unit 7. Further, the second camera 12 outputs a detection signal based on the amount of transmitted light of the received center wavelength λ1 and center wavelength λ2 to the processing unit 7.

  When the line sensor 4 has the configuration shown in FIG. 4A, the center passing through the inspection object W when the light of the center wavelengths λ <b> 1 and λ <b> 2 is irradiated from the light source unit 3. Lights with wavelengths λ1 and λ2 are split into light with central wavelength λ1 and light with central wavelength λ2 by camera 4C having a spectral function. Then, a detection signal based on the transmitted light amount of the center wavelength λ1 and a detection signal based on the transmitted light amount of the center wavelength λ2 are output to the processing unit 7.

  Further, in the case where the line sensor 4 has the configuration of FIG. 4B, the center passing through the inspection object W when the light of the center wavelengths λ 1 and λ 2 is irradiated from the light source unit 3 to the inspection object W. The fourth camera 14 receives the light with the wavelengths λ1 and λ2, and only the light with the center wavelength λ1 out of the light with the center wavelengths λ1 and λ2 passing through the inspection object W passes through the filter 16 and passes through the filter 16. The camera 15 receives light. Then, the fourth camera 14 outputs a detection signal based on the amount of transmitted light having the received center wavelengths λ 1 and λ 2 to the processing unit 7. In addition, the fifth camera 15 outputs a detection signal based on the transmission amount of the light having the center wavelength λ 1 received through the filter 16 to the processing unit 7.

  When the detection signal is input from the line sensor 4, the processing unit 7 sequentially stores the transmission amount of light having the center wavelength λ 1 in the storage unit 7 a as line light source detection information of the line sensor 4. Further, the total transmission amount (integrated value) of the transmission amount of the light having the central wavelength λ1 and the transmission amount of the light having the central wavelength λ2 is sequentially stored as the surface light source detection information of the line sensor 4 in the storage unit 7a.

  And the image acquisition part 7b acquires a line light source image from the line light source detection information memorize | stored in the memory | storage part 7a, and acquires a surface light source image from the surface light source detection information memorize | stored in the memory | storage part 7a.

  Subsequently, the seal area specifying unit 7c specifies the seal area of the seal part Wc in the inspection object W from the line light source image acquired by the image acquisition unit 7b.

  Next, the abnormality determination unit 7d detects an abnormal part from the surface light source image acquired by the image acquisition unit 7b, and the detected abnormal part exists in the seal region of the seal unit Wc specified by the seal region specifying unit 7c. Whether or not there is an abnormality in the seal area is determined based on whether or not it is present.

  Then, the display control unit 7e controls the display of the display unit 8 so as to display information such as the inspection result of the inspection object W based on the determination of the abnormality determination unit 8c, the total number of inspections, the number of non-defective products, and the total number of NG.

  Next, in the article inspection apparatus 1 having the above-described configuration, an operation when the light of the irradiation pattern 2 is irradiated from the light source unit 3 to inspect the seal portion Wc of the inspection object W will be described.

  As described above, when the inspection object W to be inspected is introduced and conveyed by the introduction-side conveyor 2a of the conveyance unit 2, the center wavelength λ1 from the region E1 of the light emitting region E of the light source unit 3 with respect to the inspection object W. , Λ2 and the central wavelength λ2 from the region E2.

  The line sensor 4 receives the light passing through the inspection object W when the light including the center wavelengths λ1 and λ2 and the light having the center wavelength λ2 are irradiated from the light source unit 3 to the inspection object W. Then, the received light is split into light having the center wavelengths λ1 and λ2, and the light having the center wavelengths λ1 and λ2 is split in any of the configurations shown in FIGS. 3A, 4A, and 4B. A detection signal based on the transmission amount of the signal is output to the processing unit 7.

  In the processing unit 7, similarly to the irradiation pattern 1 described above, the seal region of the seal portion Wc in the inspection object W is specified from the line light source image, the abnormal portion is detected from the surface light source image, and the detected abnormal portion is specified. Whether or not there is an abnormality in the seal area is determined based on whether or not it exists in the seal area of the sealed portion Wc.

  The display unit 8 displays information such as the inspection result of the inspection object W based on the determination in the predetermined unit 7, the total number of inspections, the number of non-defective products, and the total number of NG.

  As described above, in the article inspection apparatus 1 according to the present embodiment, the light emitting region E of one light source unit 3 is divided into the region E1 and the region E2 with respect to the transport direction A, and the center wavelength λ1 (or the center wavelength) from the region E1. (including λ1 and λ2) and light having a central wavelength λ2 from the region E2. The line sensor 4 receives the light emitted from the light source unit 3 and passing through the inspection object W, and sends a detection signal based on the transmission amount of the light separated for each of the center wavelengths λ1 and λ2 to the processing unit 7. Output. Then, the processing unit 7 separates the line light source image and the surface light source image from the detection information based on the detection signal from the line sensor 4 and acquires two types of transmission images. Subsequently, the processing unit 7 specifies the seal region of the seal portion Wc in the inspection object W using these two types of transmission images, and determines whether there is an abnormality in the seal region. This eliminates the need to prepare two types of light source sections by separately configuring the line light source and the surface light source, shortens the length of the apparatus, avoids an increase in the size of the apparatus, and reduces costs while also sealing the object to be inspected. The region can be inspected with high accuracy.

  At that time, among the light irradiated from the light source unit 3, the amount of light transmitted in the region E1 along the reference plane L is scattered and transmitted by the unevenness of the seal region of the seal portion Wc of the object W to be inspected ( Since the light does not reach the element of the line sensor 4 and becomes dark), light having a wavelength (λ1) included only in the light along the reference plane L is detected, and the seal region of the seal portion Wc is detected. It can be specified with high accuracy.

  The unevenness of the seal region of the seal portion Wc is caused by light from a plurality of angular directions including the reference plane L emitted from the light source unit 3, that is, light of the entire light emission region E (region E1 and region E2) of the light source unit 3. The light of the entire light emitting area E of the light source section 3 is utilized by utilizing the fact that the light receiving amount received by the element of the line sensor 4 is reduced. Can detect the abnormality of the seal region of the seal portion Wc by detecting the light of the wavelength (λ1, λ2) included in the, and inspect the entire seal region for abnormality.

  The best mode of the article inspection apparatus according to the present invention has been described above, but the present invention is not limited by the description and drawings according to this mode. That is, it is a matter of course that all other forms, examples, operation techniques, and the like made by those skilled in the art based on this form are included in the scope of the present invention.

DESCRIPTION OF SYMBOLS 1 Item inspection apparatus 2 Conveyance part 2a Introduction side conveyor 2b Discharge side conveyor 2c Conveyance surface 3 Light source part 4 Line sensor 4a Light-receiving surface 5 Operation part 6 Drive control part 7 Processing part 7a Storage part 7b Image acquisition part 7c Seal area | region identification part 7d Abnormality judgment unit 7e Display control unit 8 Display unit A Transport direction E Light emission region E1, E2 region L Reference plane S Air gap W Inspected object Wa Packaging material Wb Contents Wc Sealing unit Wd Foreign material We Boundary X Noise λ1, λ2 Center wavelength θ Incident angle with respect to the transfer surface

Claims (5)

The inspection object (W) in which the contents (Wb) are wrapped in the packaging material (Wa) is conveyed to irradiate the inspection object with light, and the transmitted light is detected based on the transmitted image. An article inspection apparatus (1) for inspecting a sealing area of a packaging material,
A line sensor (4) in which a plurality of elements for detecting the transmitted light are arranged in a direction crossing a transport direction (A) of the inspection object;
A plane that intersects each element of the line sensor and is perpendicular to the transport surface (2c) on which the inspection object is transported is defined as a reference plane (L), and a plurality of angles with the reference plane as the center The light source unit 3 emits the second light from the direction along the reference plane that includes at least the wavelength (λ1) different from the wavelength (λ2) of the first light. When,
A processing unit (7) that identifies the seal region based on a detection signal obtained from the line sensor in accordance with light of each wavelength emitted by the light source unit, and determines whether there is an abnormality in the seal region; An article inspection apparatus comprising: The said processing part (7) specifies the said seal | sticker area | region from the detection signal when the said line sensor (4) receives the light of the wavelength ((lambda) 1) of the light of the said reference plane (L), It is characterized by the above-mentioned. Item inspection apparatus according to Item 1. The line sensor (4) comprises a plurality of cameras (11, 12) having sensitivities corresponding to the wavelengths (λ1, λ2) of a plurality of lights emitted from the light source unit (3). Item inspection apparatus according to Item 1 or 2. 3. The article inspection apparatus according to claim 1, wherein the line sensor (4) comprises a single camera (13) having a spectroscopic function. The line sensor (4) is provided on a front surface of a plurality of cameras (14, 15) having sensitivity to a plurality of wavelengths of light emitted from the light source unit (3) and any of the plurality of cameras. 3. The article inspection apparatus according to claim 1, further comprising a filter (16) that allows the light on the reference surface to pass through in correspondence with the wavelength (λ1) of the light on the reference surface (L).

Images