JP3943002B2 - X-ray inspection apparatus and inspection method - Google Patents

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an X-ray inspection apparatus and an inspection method for inspecting a conveyed article.
[0002]
[Prior art]
Conventionally, when inspecting products with multiple contents wrapped in packaging materials such as Wiener and chicken nuggets, products that are judged as rejected products are broken, and defective products are identified from among the multiple contents And follow the process of repacking only good products.
Therefore, using a conventional X-ray inspection apparatus, the re-inspection of such a product re-inspects a plurality of contents individually in a separate process after the inspection of the normal product is completed. Therefore, it took a lot of time to complete the inspection.
[0003]
An X-ray inspection apparatus for solving the above problem has been proposed (see, for example, Patent Document 1). In such an apparatus, normal inspection and re-inspection can be performed in parallel, so that the inspection time can be shortened. Moreover, since the X-ray source and the detection unit are shared, the equipment cost can be reduced.
[0004]
[Patent Document 1]
Japanese Patent Laid-Open No. 1-254848 (page 2 to page 3, FIG. 2)
[0005]
[Problems to be solved by the invention]
However, this apparatus has the following problems.
1) At the time of re-inspection, since a plurality of articles are inspected at the same time as in the normal inspection, it is impossible to specify which of the individual articles is defective. Therefore, in the case of a product in which a plurality of articles are packaged, it can be excluded only in packaging units including both defective products and non-defective products.
2) In the re-inspection, just narrowing the width of the path through which the article passes, and the inspection conditions such as the setting of the threshold value that is the criterion of the X-ray intensity and pass / fail criteria are the same as the normal inspection, The inspection accuracy of re-inspection is equivalent to that of normal inspection. On the other hand, in the X-ray inspection, the inspection result may change depending on the direction of contamination of the foreign matter. Therefore, in the re-inspection, if the conditions are the same as the normal inspection, the re-inspection may all pass. There is no sense of re-examination.
[0006]
Therefore, an object of the present invention is to reliably eliminate a product in which foreign matters are mixed while performing re-inspection and normal inspection in parallel.
[0007]
[Means for Solving the Problems]
In order to achieve the above object, an inspection apparatus according to the first aspect of the present invention includes a transport unit that transports an article, and a normal inspection section and a re-inspection section that are partitioned in a width direction perpendicular to the transport direction in which the article is transported. The X-ray source for irradiating the article conveyed through the normal inspection unit and the re-inspection unit with X-rays, a line sensor for detecting X-rays transmitted through the article, and the normal inspection unit and the re-inspection unit For each part of the line sensor, a first pass / fail judgment is made by comparing the storage unit storing the set first and second threshold values, and the first threshold value and the detection value in the normal inspection unit. And a control means for comparing the second threshold value set to a value smaller than the first threshold value and the detection value in the reexamination unit to make a second pass / fail judgment. .
[0008]
On the other hand, the apparatus of the second invention is provided in parallel with the normal inspection unit that inspects the article by irradiating the article with X-rays while conveying the article, and is defective in the normal inspection. An X-ray inspection apparatus including a re-inspection unit that re-inspects an article that has been determined to have a threshold value that is a criterion for pass / fail that is smaller than that of the normal inspection unit. The ratio between the area of the inspection unit and the area of the re-inspection unit can be changed .
[0009]
Test method of the present invention was determined and performing normal inspection by supplying products several contents double it is packaged in packaging material to normal inspection unit, failed by the normal inspection not A step of breaking the packaging of the acceptable product, and a step of supplying the contents of the rejected product to the re- inspection unit in a state of being separated from each other in the transport direction and performing a re-inspection. .
[0010]
In the present invention, since the threshold value of the pass / fail criterion in the re-inspection is set to a small value, when it is determined that a defective product exists in the normal inspection, the detected value varies due to the change in the posture of the foreign matter. Even if it occurs, there is no possibility of detection failure of the defective product in the re-inspection.
[0011]
In the present invention, “the threshold value for pass / fail criteria is set to a small value” means that the re-inspection unit has a stricter acceptance standard value than the normal inspection unit.
[0012]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, an embodiment of the present invention will be described with reference to the drawings.
As shown in FIG. 1, the X-ray inspection apparatus 1 for an article includes a conveyor (conveying means) 5 and an optical system 20. The optical system 20 includes an X-ray source 21 and a line sensor 22. The X-ray source 21 generates X-rays L and irradiates the X-rays L toward the line sensor 22.
[0013]
A resin plate (partitioning means) 7 is provided above the conveying surface 51 of the conveyor 5, and a space for conveying articles is divided into a width direction D orthogonal to the conveying direction Y, and the normal inspection unit 2 and the reinspection unit 3. It is divided into and. In the normal inspection unit 2, a product (article) M in which a plurality of contents (articles) q are packaged with a packaging material is conveyed. On the other hand, the re-inspection unit 3 individually conveys the contents q taken out by breaking the product M (in a state of being separated from each other in the conveyance direction Y).
[0014]
The X-ray source 21 irradiates both the product M and the contents q conveyed through the normal inspection unit 2 and the re-inspection unit 3 with X-rays L, respectively. The line sensor 22 is arranged below the normal inspection unit 2 and the re-inspection unit 3 so as to detect the X-ray L transmitted through the product M and the content q.
Distributing devices 9a and 9b for line-out of defective products are provided downstream of the normal inspection unit 2 and the re-inspection unit 3, respectively.
[0015]
As shown in FIG. 2, the line sensor 22 is formed by arranging a large number of detection elements S _i (i = 1 to n) in a substantially straight line. Among the numerous detection elements S _i , the first to m-th m first detection elements S _{1 to} S _m are arranged at positions corresponding to the normal inspection unit 2 and are transmitted through the product M. L is detected. On the other hand, corresponding to one (m + c + 1) -th from to n-th (n- (m + c)) pieces of the second detection element S _{m + c +} 1 ~S _n is the re-inspection unit 3 of the plurality of detection elements S _i The X-ray L which is arrange | positioned in the position and permeate | transmitted the content q is detected.
The c third detection elements from the (m + 1) th detection element S _{m + 1} to the (m + c) th detection element S _{m + c} are arranged at positions corresponding to the resin plate 7.
[0016]
Next, the control configuration of the X-ray inspection apparatus will be described.
As shown in FIG. 3A, the X-ray inspection apparatus 1 has a microcomputer (control means) 10. The microcomputer 10 is connected to the X-ray source 21, the line sensor 22, and the local control device 25 through an interface (not shown). The local control device 25 controls the operation of the conveyor 5 and the operations of the sorting devices 9a and 9b.
[0017]
The microcomputer 10 includes a CPU 11 and a memory (storage unit) 12.
The memory 12 includes a threshold storage unit 12a. As shown in FIG. 3B, the threshold value storage unit 12a includes a first threshold value set for the first detection elements S _{1 to} S _m and the second detection elements S _{m + c + 1} to the second threshold value are stored in advance set for S _n. The second threshold is set to a value smaller than the first threshold.
[0018]
Here, since the product M and the contents q do not pass over the third detection elements S _{m + 1 to} S _{m + c} as shown in FIG. 2, the third detection elements S _{m + 1 to} S _{m A} threshold value is not set for _{+ c} , and detection values from the third detection elements S _{m + 1 to} S _{m + c} are ignored in the pass / fail determination described later.
[0019]
The CPU 11 performs a pass / fail determination process for the product M and the contents q in the following manner with respect to the detection value of the detection element S _i of the line sensor 22.
(1) the normal detection value in the inspection unit 2, i.e. by comparing the detection value and the first threshold value of the first detection element S ₁ to S _m, whether the foreign matter in the product M is attached to contamination The first pass / fail determination is performed. When the detection values of the first detection elements S _{1 to} S _m are smaller than the first threshold value (when the amount of X-ray transmission is small), the product M is rejected, and the distribution device 9a Send a sort signal to.
(2) in parallel with said first acceptance judgment, the detected value of the re-examination section 3, i.e. that the detection value of the second detection element S _{m + c + 1} ~S _n comparing said second threshold value Then, a second pass / fail determination is made as to whether or not foreign matter is attached to or mixed in the content q. If the detected value of the said than second threshold second detecting element S _{m + c + 1} ~S _n is a small value (when the amount of transmission of X-rays is small), the the contents q Fail Then, a distribution signal is transmitted to the distribution device 9b.
(3) The detection values of the third detection elements S _{m + 1 to} S _{m + c} are ignored and no pass / fail determination is performed.
[0020]
Next, an inspection method using the present X-ray inspection apparatus will be described.
An operator performs a predetermined operation to start the apparatus. Note that a product to be inspected may be specified by a controller (not shown), and the first and second threshold values may be set and changed based on the specification.
When the apparatus is started, first, the commodity M is supplied to the normal inspection unit 2 by the operator. When the product M conveyed by the conveyor 5 passes through the optical system 20 in the normal inspection unit 2, X-rays transmitted through the product M are detected by the first detection elements S _{1 to} S _m . Based on the detection values from the first detection elements S _{1 to} S _m , the CPU 11 performs the first pass / fail determination, and the product M determined to be rejected is lined out.
[0021]
When re-inspecting the product M determined to be unacceptable in the normal inspection, the packaging of the unacceptable product is broken by the operator. The contents q of the rejected product thus obtained are individually supplied to the reinspection unit 3.
The X-ray L is irradiated to the supplied contents q to recheck unit 3, X-ray L transmitted through the contents q is detected in the second detecting element _{S m + c + 1 ~S n} , CPU11 Thus, the second pass / fail determination is performed. As a result of the second pass / fail determination, the contents q determined to be unacceptable are individually lined out by the downstream sorting device 9b.
[0022]
By the way, the ratio of the region (width) of the normal inspection unit 2 and the region (width) of the re-inspection unit 3 may be changeable. The change of the region changes the position of the resin plate 7 in the width direction D, and the first detection elements S _{1 to} S _m and the second detection elements S _{m + c +} according to the position of the resin plate 7. the proportion of ₁ ~S _n to change settings. For example, after the position of the resin plate 7 is changed, X-rays are irradiated from the X-ray source 21 toward the line sensor 22 without changing the position of the resin plate 7, and the line sensor 22 detects the resin plate 7. and the portions S _{m + 1} ~S _{m + c} to the boundary, as the first detecting element S ₁ to S _m and the second detection element S _{m + c + 1} ~S _n is automatically set Also good.
[0023]
Further, an image may be created based on a detection signal from the detection element, and a foreign object image as an X-ray inspection result may be printed out. At that time, if the output level is printed together with the level meter of the threshold value for each trigger item, it is possible to know the margin at the time of foreign object detection by checking the content of the level meter after printing. Thereby, the stability of detection can be confirmed at any time.
[0024]
Further, the X-ray inspection apparatus may be connected to a general-purpose network so that the X-ray inspection apparatus and a personal computer on the network are linked. By using this X-ray inspection system to inform the administrator's mobile phone or personal computer of information such as changes in system status, the administrator does not need to be at the site, and all status changes can be made anywhere. In addition, it is possible to obtain more detailed information by accessing the network.
[0025]
As described above, the preferred embodiments have been described with reference to the drawings. However, those skilled in the art will readily understand various changes and modifications within the obvious scope by looking at the present specification.
For example, two sets of X-ray sources and line sensors may be provided, and two different cross sections may be inspected to further improve the inspection accuracy.
Moreover, the object of normal inspection is not necessarily limited to the one wrapped in the packaging material.
In addition, the first threshold value and the second threshold value need not be constant values, and the first threshold value (and / or the second threshold value) may be different from each other depending on the position of the detection element.
In this case, the average value of the second threshold is set to a value smaller than the average value of the first threshold.
Accordingly, such changes and modifications are to be construed as within the scope of the present invention as defined by the claims.
[0026]
【The invention's effect】
As described above, according to the present invention, normal inspection and re-inspection can be performed in parallel on one line, so that inspection efficiency is remarkably improved.
In particular, since the threshold value of the re-inspection unit is set to a smaller value than the normal inspection unit, the sensitivity of the re-inspection is increased, so that defective products can be reliably identified.
[0027]
Furthermore, if a partition means is provided and a threshold value is set according to the area partitioned by the partition means, normal inspection and re-inspection can be performed in parallel and individually. Become more certain.
Further, if both the normal inspection and the re-inspection are performed with one line sensor, the equipment cost can be suppressed.
[0028]
In addition, if the article is transported in the horizontal direction, compared to a device that drops the article in the vertical direction and inspects it during the fall, the individual transport of the unwrapped single item is carried (separately transported separately) Since it becomes easy, a defective article can be identified easily and reliably.
[0029]
Further, if the ratio between the two inspection units can be changed, the inspection according to the size of the article or the contents can be performed, so that the versatility of the apparatus is increased.
[Brief description of the drawings]
FIG. 1 is a schematic perspective view showing an X-ray inspection apparatus according to the present invention.
FIG. 2 is a schematic front view showing a main part of the X-ray inspection apparatus.
FIG. 3A is a schematic configuration diagram showing an X-ray inspection apparatus, and FIG. 3B is a chart showing storage contents of a storage unit.
[Explanation of symbols]
2: Normal inspection unit 3: Re-inspection unit 5: Conveyor (conveying means)
7: Resin plate (partitioning means)
10: Microcomputer (control means)
11: CPU
12: Memory (storage unit)
21: X-ray source 22: Line sensor S _i : Detection elements S _{1 to} S _m : First detection elements S _{m + c + 1 to} S _n : Second detection elements S _{m + 1 to} S _{m + c} : Third Detection element M: commodity (article)
q: Contents (article)
L: X-ray Y: Transport direction D: Width direction

Claims (9)

Conveying means for conveying the article;
A normal inspection section and a re-inspection section partitioned in the width direction orthogonal to the transport direction in which the article is transported ;
An X-ray source for irradiating an article conveyed through the normal inspection unit and the re-inspection unit with X-rays;
A line sensor for detecting X-rays transmitted through the article;
For each part of the line sensor corresponding to the normal inspection part and the re-inspection part , a storage part for storing the set first and second threshold values , respectively ,
The first threshold value and the detection value in the normal inspection unit are compared to make a first pass / fail determination, and the second threshold value set to a value smaller than the first threshold value and the detection in the re-inspection unit An X-ray inspection apparatus comprising control means for comparing the values and performing a second pass / fail determination. In claim 1 ,
One x-ray source;
There is one line sensor,
The first and second thresholds are set for the one line sensor,
An X-ray inspection apparatus capable of performing the first and / or second pass / fail judgment by detecting X-rays from the one X-ray source by the one line sensor. In claim 1 ,
The line sensor is formed by arranging a large number of detection elements in a substantially straight line, and is arranged so as to straddle the divided two regions, and a plurality of second sensors that detect X-rays in the normal inspection unit. The first threshold value is set for one detection element, and the second threshold value is set for a plurality of second detection elements that detect X-rays in the reexamination unit. X-ray inspection equipment. In claim 1, 2 or 3 ,
An X-ray inspection apparatus characterized in that a conveying means for conveying an article conveys the article in a substantially horizontal direction. In any one of Claims 1 thru | or 4 ,
An X-ray inspection apparatus capable of changing a ratio between the area of the normal inspection section and the area of the re-inspection section. An inspection method using the X-ray inspection apparatus according to any one of claims 1 to 5 ,
Supplying the normal inspection unit with a product in which a plurality of contents are packaged with a packaging material, and performing a normal inspection;
A step of breaking the packaging of the rejected product determined to be rejected in the normal inspection;
A step of supplying the contents of the rejected products to the re-inspection unit in a state of being separated from each other in the transport direction and performing a re-inspection. A normal inspection unit for inspecting an article by irradiating the article with X-rays while conveying the article;
An X-ray inspection apparatus provided in parallel with the normal inspection unit and provided with a re-inspection unit for re-inspecting an article determined to be defective in the normal inspection,
The re-inspection unit is set to a threshold value that is a criterion for pass / fail than the normal inspection unit,
An X-ray inspection apparatus capable of changing a ratio between the area of the normal inspection section and the area of the re-inspection section. An X-ray inspection method using the X-ray inspection apparatus according to claim 7 ,
Supplying the normal inspection unit with a product in which a plurality of contents are packaged with a packaging material, and performing a normal inspection;
A step of breaking the packaging of the rejected product determined to be rejected in the normal inspection;
A step of supplying the contents of the rejected products to the re-inspection unit in a state of being separated from each other in the transport direction and performing a re-inspection. While conveying the article, the normal test 査部 inspecting the article is irradiated with X-rays to the article,
An X-ray inspection method using an X-ray inspection apparatus provided in parallel with the normal inspection unit and provided with a re-inspection unit for re-inspecting an article determined to be defective in the normal inspection ,
The re-inspection unit is set to a threshold value that is a criterion for pass / fail than the normal inspection unit,
Supplying the normal inspection unit with a product in which a plurality of contents are packaged with a packaging material, and performing a normal inspection;
A step of breaking the packaging of the rejected product determined to be rejected in the normal inspection;
A step of supplying the contents of the rejected products to the re-inspection unit in a state of being separated from each other in the transport direction and performing a re-inspection.

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