X-ray inspection equipment and item handling system

Abstract

To provide a worker with information showing whether a raw material to transfer is transferred with a proper quantity.SOLUTION: An X-ray inspection device 1 includes: a transfer unit 5 for transferring an object G; an X-ray irradiation unit 6 for irradiating the object G transferred by the transfer unit 5 with an X-ray; an X-ray detection unit 7 for detecting an X-ray having passed through the object G; an image generation unit 10A for generating an X-ray transmission image on the basis of the result of detection by the X-ray detection unit 7; and a calculation unit 10C for calculating the total quantity of the object G transferred per predetermined time by the transfer unit 5 on the basis of the X-ray transmission image.SELECTED DRAWING: Figure 3

Description

Technical Field

[0001] One aspect of the present invention relates to an X-ray inspection apparatus and an article processing system.

Background Art

[0002] For example, Patent Document 1 describes a production line of products including a plurality of article processing apparatuses. In such a production line for producing products, a conveyance path for conveying raw materials or the like, which is a stage before being bagged or a stage before being processed, may be provided.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] In such a production line, when conveying a larger amount of raw materials than the estimated amount, problems such as an increase in the overlap of raw materials and a decrease in the inspection accuracy in the inspection apparatus in the downstream process, or raw materials exceeding the processing capacity and being unable to be properly processed may occur. On the other hand, when conveying a smaller amount of raw materials than the estimated amount, a problem of a decrease in production capacity occurs. Therefore, an operator who manages the production line has a desire to appropriately adjust the amount of raw materials flowing through the conveyance path.

[0005] Therefore, an object of one aspect of the present invention is to provide an X-ray inspection apparatus and an article processing system that can provide an operator with information on whether the amount of raw materials conveyed in a conveyance path is appropriate.

Means for Solving the Problems

[0006] An X-ray inspection apparatus according to one aspect of the present invention comprises a transport unit for transporting articles, an X-ray irradiation unit for irradiating the articles transported by the transport unit with X-rays, an X-ray detection unit for detecting X-rays that have passed through the articles, an image generation unit for generating an X-ray transmission image based on the detection results from the X-ray detection unit, and a calculation unit for calculating the total amount of articles transported by the transport unit per predetermined time based on the X-ray transmission image.

[0007] In this configuration, the total amount of items transported per predetermined time by the transport unit is calculated based on the X-ray transmission image. In other words, the X-ray inspection device can provide the operator with information on whether the amount of raw materials transported from the X-ray inspection device to the downstream process (in other words, the amount of raw materials supplied from the upstream process to the X-ray inspection device) is appropriate. As a result, the operator, having obtained the calculated total amount, can, for example, adjust the item processing device in the upstream process so that the transport amount is appropriate.

[0008] In one aspect of the present invention, the X-ray inspection apparatus may further include a display unit for displaying the total quantity, and the calculation unit may cause the display unit to display a warning when the total quantity falls outside a first predetermined range that includes a first upper limit and a first lower limit stored in advance. In this configuration, it is possible to explicitly indicate to the worker that the amount of raw materials being transported is inappropriate.

[0009] In an X-ray inspection apparatus according to one aspect of the present invention, the calculation unit may cause an article processing device, which is provided upstream and / or downstream of the X-ray inspection apparatus and processes articles, to execute error processing when the total quantity falls outside a second predetermined range that includes a second upper limit value greater than a pre-stored first upper limit value and a second lower limit value less than the first lower limit value. In this configuration, the necessary processing is automatically executed without the operator having to obtain the total quantity calculated by the calculation unit and take any action on the article processing device. This reduces the burden on the operator.

[0010] In one aspect of the present invention, the article processing system comprises the above-mentioned X-ray inspection device and an article supply device as one of the article processing devices that supply articles to the X-ray inspection device. The calculation unit may be controlled to change the article supply amount, which is preset in the article supply device, when the total quantity falls outside a first predetermined range. In this configuration, the necessary processing is automatically performed in the article processing device that constitutes the article processing system without the operator having to obtain the total quantity calculated by the calculation unit and take any action on the article processing device. This reduces the burden on the operator. [Effects of the Invention]

[0011] According to one aspect of the present invention, it is possible to provide workers with information on whether the amount of raw materials being transported in the transport path is appropriate or not. [Brief explanation of the drawing]

[0012] [Figure 1] Figure 1 is a diagram showing the configuration of an X-ray inspection apparatus according to one embodiment. [Figure 2] Figure 2 is a diagram showing the internal configuration of the shield box shown in Figure 1. [Figure 3] Figure 3 is a block diagram showing the functional configuration of an X-ray inspection device. [Figure 4] Figure 4 shows an example of the inspection results screen displayed on the display operation unit. [Figure 5] Figure 5 illustrates a method for calculating the total amount of goods transported per unit time. [Figure 6] Figure 6 is a diagram showing the configuration of the article processing system according to Modification Example 1. [Modes for carrying out the invention]

[0013] An embodiment of the present invention will be described below with reference to the drawings. In the description of the drawings, the same elements are denoted by the same reference numerals, and redundant descriptions are omitted.

[0014] As shown in Figure 1, the X-ray inspection device 1 comprises a main body 2, support legs 3, a shield box 4, a transport unit 5, an X-ray irradiation unit 6, an X-ray detection unit 7, a display operation unit 8, and a control unit 10. The X-ray inspection device 1 transports an item G while generating an X-ray transmission image of the item G, and performs inspection of the item G (for example, checking the number of items stored, checking for foreign objects, checking for missing items, checking for cracks and chips, etc.) based on the X-ray transmission image.

[0015] Before inspection, items G are brought into the X-ray inspection device 1 by an input conveyor 51. The transport speed of the input conveyor 51 is approximately the same as the transport speed of the item processing device connected upstream. After inspection, items G are discharged from the X-ray inspection device 1 by an output conveyor 52. The transport speed of the output conveyor 52 is approximately the same as the transport speed of the item processing device connected downstream. Items G determined to be defective by the X-ray inspection device 1 are sorted out of the production line by a sorting device 20 located downstream of the output conveyor 52. Items G determined to be good by the X-ray inspection device 1 pass straight through the sorting device 20.

[0016] The sorting device 20 is a device that removes items G that have been determined to be defective by the X-ray inspection device 1 from the transport path. Examples of sorting devices include arm-type sorting devices using arms, drop-up belt-type sorting devices, pusher-type sorting devices using pusher devices, drop-flap type sorting devices, air-jet type sorting devices, and fin-type sorting devices.

[0017] Article G does not have a fixed size, shape, or thickness (in other words, it does not have a fixed weight), and is a so-called bulk product. Examples of bulk products include dry products such as nuts, dried fruits, dried ingredients, and rice crackers, and wet products such as minced meat, meat, seafood, frozen foods, and agricultural products. When such bulk products are transported by the transport unit 5, there are parts where articles G overlap with each other, and parts where gaps are formed between adjacent articles G.

[0018] The apparatus main body 2 houses the control unit 10 and the like. The support legs 3 support the apparatus main body 2. The shield box 4 is provided on the apparatus main body 2. The shield box 4 prevents the leakage of X-rays (electromagnetic waves) to the outside. Inside the shield box 4, an inspection area R where inspection of the article G by X-rays is carried out is provided. The shield box 4 is formed with a carry-in port 4a and a carry-out port 4b. The article G before inspection is carried into the inspection area R through the carry-in port 4a from the carry-in conveyor 51. The article G after inspection is carried out from the inspection area R to the carry-out conveyor 52 through the carry-out port 4b. X-ray shielding curtains (not shown) for preventing the leakage of X-rays are provided at each of the carry-in port 4a and the carry-out port 4b.

[0019] The conveyance unit 5 is a member for conveying the article G and is arranged so as to penetrate the center of the shield box 4. The conveyance unit 5 conveys the article G along the conveyance direction A from the carry-in port 4a through the inspection area R to the carry-out port 4b. The conveyance unit 5 is, for example, a belt conveyor stretched between the carry-in port 4a and the carry-out port 4b. Note that the conveyance unit 5 which is a belt conveyor may project outside the carry-in port 4a and the carry-out port 4b. The conveyance speed of the conveyance unit 5 substantially coincides with that of the carry-in conveyor 51 and the carry-out conveyor 52.

[0020] As shown in FIGS. 1 and 2, the X-ray irradiation unit 6 is an electromagnetic wave irradiation unit (X-ray source) arranged inside the shield box 4. The X-ray irradiation unit 6 has, for example, an X-ray tube that emits X-rays and an aperture unit that spreads the X-rays emitted from the X-ray tube in a fan shape within a plane perpendicular to the conveyance direction A. The X-rays irradiated from the X-ray irradiation unit 6 may include X-rays in various energy bands from low energy (long wavelength) to high energy (short wavelength).

[0021] The X-ray detection unit 7 is a sensor element that detects electromagnetic waves. The X-ray detection unit 7 is located inside the shield box 4 and is positioned opposite the X-ray irradiation unit 6 in the vertical direction. The X-ray detection unit 7 may be capable of detecting X-rays in a specific energy band, or it may be capable of detecting X-rays using a photon counting method. The X-ray detection unit 7 may be a direct conversion type detection unit or an indirect conversion type detection unit. The sensors are arranged, for example, in a direction (width direction) perpendicular to the transport direction and vertical direction of the transport unit 5. The elements may be arranged not only in the width direction but also in the transport direction. That is, the X-ray detection unit 7 may be a line sensor or a group of sensors arranged two-dimensionally. The sensors are, for example, photon detection type sensors such as CdTe semiconductor detectors.

[0022] As shown in Figure 1, the display and operation unit 8 is provided on the main body 2 of the device. The display and operation unit 8 displays various information and accepts input operations for various conditions from the outside. The display and operation unit 8 is, for example, a liquid crystal display and displays an operation screen as a touch panel. In this case, the operator can input various conditions via the display and operation unit 8.

[0023] The control unit 10 is located within the main body 2 of the device. The control unit 10 controls the operation of each part of the X-ray inspection device 1 (in this embodiment, the transport unit 5, the X-ray irradiation unit 6, the X-ray detection unit 7 and the display operation unit 8, and the distribution device 20 located downstream of the X-ray inspection device 1). The control unit 10 includes a processor such as a CPU (Central Processing Unit), memory such as ROM (Read Only Memory) and RAM (Random Access Memory), and storage such as an SSD (Solid State Drive). The ROM contains a program for controlling the X-ray inspection device 1. As shown in Figure 3, the control unit 10 includes an image generation unit 10A, an inspection unit 10B, and a calculation unit 10C. In the control unit 10, the image generation unit 10A, the inspection unit 10B, and the calculation unit 10C are configured as software. However, each of these parts may be configured as hardware.

[0024] The image generation unit 10A receives the signal output from the X-ray detection unit 7 and converted using A / D. The inspection unit 10B generates an X-ray transmission image of the item G based on the signal and inspects the item G based on the X-ray transmission image. The inspection unit 10B checks whether or not foreign matter is present in the item G being transported into the inspection area R. In this embodiment, when inspecting bulk product items G, the inspection unit 10B repeatedly performs inspections for each predetermined transport area, for example, for groups of items transported per second. In other words, the inspection unit 10B performs inspections in units of X-ray transmission images of a predetermined length in the transport direction. The inspection unit 10B displays an inspection result screen 80, for example, as shown in Figure 4, on the display operation unit 8. The inspection result screen 80 includes, for example, a foreign matter display unit 81 that displays the location of the detected foreign matter, and a result display unit 83 that displays the inspection result, such as OK or NG.

[0025] The calculation unit 10C calculates the total amount of items G transported per unit time by the transport unit 5 based on the X-ray transmission image. In other words, the calculation unit 10C calculates the total amount of items G passing through the X-ray inspection device 1 per unit time. An example of the total amount is weight (mass), which can be calculated by the method detailed below. Alternatively, the total amount may be volume (capacity) which can be calculated based on the weight and density of the items G.

[0026] The calculation unit 10C determines the article region in which article G exists from the X-ray transmission image of article G generated as described above. The calculation unit 10C estimates the weight of article G in each article region by applying image processing to the article region. This weight estimation process is performed based on the following principle, utilizing the property that in an X-ray transmission image, materials that are thicker in the direction of X-ray irradiation appear darker.

[0027] The brightness I of a pixel that captures a substance of thickness t on an X-ray transmission image is expressed by the following equation (1), where I0 is the brightness of a pixel in a region where no substance exists. I / I0=e -μt ...(1) Here, μ is the linear absorption coefficient, which depends on the energy of the X-rays and the type of material. Solving equation (1) for the thickness t of the material, we get equation (2) below. t = -1 / μ × ln(I / I0) ... (2)

[0028] Furthermore, the weight of a minute part of object G is proportional to the thickness of that minute part. Therefore, the weight m of a minute part of object G captured by a pixel with brightness I can be approximately calculated using the following equation (3) with an appropriate constant α. m = -αln(I / I0) ... (3) The calculation unit 10C estimates the total weight of item G by calculating and summing the weights m corresponding to all pixels (item regions) that make up item G.

[0029] Next, a method for calculating the total amount (e.g., weight or volume) of articles G transported per unit time by the transport unit 5 will be described using the weight estimation method described above. As described above, the X-ray inspection device 1 repeatedly performs inspection for each predetermined transport area, for example, for each group of articles transported per second. In addition to this, it repeatedly estimates the weight for each group of articles transported per second.

[0030] Figure 5 shows X-ray transmission images of items G being transported into the inspection area R, acquired continuously every second. Each image U (U1, U2, ..., UN) shown in Figure 5 is an image of a group of items transported in one second (hereinafter also referred to as a unit image U). The calculation unit 10C adds the weight estimates obtained from each of the six unit images U to calculate the estimated weight of items G transported in six seconds (i.e., the total amount of items G transported in six seconds). Then, the calculation unit 10C multiplies the estimated weight of items G transported in six seconds by 10 to calculate the weight of items G per minute transported by the transport unit 5 (i.e., the total amount of items G transported per unit time).

[0031] More specifically, the calculation unit 10C calculates the total amount of goods G transported per minute based on five X-ray transmission images acquired up to 5 seconds prior to the acquisition of a predetermined unit image U. For example, when unit image U6 is acquired, the total amount of goods G transported per minute is calculated based on unit image U6 and the six unit images U1 to U5. Similarly, when unit image U7 is acquired, the total amount of goods G transported per minute is calculated based on unit image U7 and the six unit images U2 to U6.

[0032] The calculation unit 10C displays the calculated total amount of goods G transported per minute in the display area 85 of the inspection result screen 80 shown in Figure 4. The total amount of goods G transported per minute displayed in the display area 85 switches every second. In addition to or instead of displaying the total amount of goods G transported per minute displayed in the display area 85, the calculation unit 10C may also display the words "over" or "under" which are stored in association with the total amount calculated as described above. When the calculated total amount of goods G transported per minute falls outside the first predetermined range which includes a first upper limit and a first lower limit that have been stored in advance, the calculation unit 10C causes a warning to be displayed on the inspection result screen 80 on the display operation unit 8. In addition to or instead of displaying a warning, the calculation unit 10C may also output a warning sound.

[0033] When the calculated total amount of goods G per minute falls outside a second predetermined range, which includes a second upper limit value greater than a pre-stored first upper limit value and a second lower limit value less than a pre-stored first lower limit value, the calculation unit 10C causes the goods processing equipment, which is provided upstream and / or downstream of the X-ray inspection device 1 and processes the goods G, to execute error processing. Examples of error processing include, for example, causing the goods processing equipment provided upstream and / or downstream to display that the amount of goods G supplied is too much or too little, or causing the goods processing equipment provided upstream to stop supplying goods G or to change the supply amount.

[0034] The effects and advantages of the X-ray inspection apparatus 1 of the above embodiment will now be explained. In the X-ray inspection apparatus 1 of the above embodiment, the total amount of articles G transported per predetermined time by the transport unit 5 is calculated based on the X-ray transmission image. The X-ray inspection apparatus 1 can provide the operator with information via the display operation unit 8 on whether the amount of raw materials transported from the X-ray inspection apparatus 1 to the downstream process (in other words, the amount of raw materials supplied from the upstream process to the X-ray inspection apparatus 1) is appropriate. As a result, the operator who has obtained the calculated total amount can, for example, adjust the article processing device in the upstream process so that the supply amount is appropriate. Furthermore, by the operator appropriately adjusting the supply amount, for example, the sorting device 20 can prevent the sorting from not being able to keep up if the supply amount is too high, or prevent many articles from being discarded together. This makes it possible to improve the sorting accuracy of the sorting device 20 (the probability of correctly sorting defective products as defective products).

[0035] In the X-ray inspection apparatus 1 of the above embodiment, the calculation unit 10C causes the display operation unit 8 to display a warning when the total amount falls outside a first predetermined range that includes a first upper limit and a first lower limit that have been stored in advance. This makes it possible to explicitly show the worker that the amount of raw materials being transported is inappropriate.

[0036] In the X-ray inspection apparatus 1 of the above embodiment, the calculation unit 10C causes the article processing apparatus provided upstream and / or downstream of the X-ray inspection apparatus 1 to execute error processing when the total amount falls outside a second predetermined range, which includes a second upper limit value greater than a pre-stored first upper limit value and a second lower limit value less than a pre-stored first lower limit value. With this configuration, the necessary processing is automatically executed without the operator having to obtain the total amount calculated by the calculation unit 10C and take any action on the article processing apparatus. This reduces the burden on the operator.

[0037] Although one embodiment has been described above, one aspect of the present invention is not limited to the above embodiment. Various modifications are possible without departing from the spirit of the invention.

[0038] (Variation 1) Hereinafter, a modification 1 of the present invention will be described. As shown in Figure 6, modification 1 of the present invention can be configured as an article processing system 100 that is used, for example, in a frozen food production line and comprises the above-mentioned X-ray inspection device 1, a first article processing device (article supply device) 60 provided upstream of the X-ray inspection device 1, a second article processing device 70 provided downstream of the X-ray inspection device 1, a conveying device 55A provided between the first article processing device 60 and the X-ray inspection device 1, and a conveying device 55B provided between the X-ray inspection device 1 and the second article processing device 70.

[0039] An example of the first product processing device 60 is a food processing device. For example, it manufactures product G, which will become frozen food before freezing, and supplies it to the downstream process. An example of the second product processing device 70 is a freezing device. The second product processing device 70 freezes the product G that is transported from the upstream process. Downstream of the second product processing device 70, although not shown in the diagram, various inspection devices, packaging devices, boxing devices, etc., are arranged. In such a product processing system 100, the X-ray inspection device 1 inspects the product G transported (supplied) from the first product processing device 60 in the upstream process for the presence or absence of foreign matter, and calculates the total amount of product G supplied from the first product processing device 60. Note that the foreign matter inspection and the method of calculating the total amount in the X-ray inspection device 1 are the same as in the above embodiment, so an explanation is omitted here.

[0040] The X-ray inspection device 1, the first item processing device 60, and the second item processing device 70 are configured to communicate with each other via a network N, such as a wired or wireless network. The calculation unit 10C of the X-ray inspection device 1 causes the first item processing device 60 and the second item processing device 70 to perform error processing when the calculated total amount of items G per minute falls outside a first predetermined range that includes a first upper limit and a first lower limit that are stored in advance, and when it falls outside a second predetermined range that includes a second upper limit that is greater than the first upper limit and a second lower limit that is smaller than the first lower limit that are stored in advance.

[0041] Specifically, when the calculated total amount of items G per minute falls outside the first predetermined range, the calculation unit 10C, via the control unit 62 of the first item processing device 60 connected via the network N, illuminates the abnormality lamp 61 provided on the first item processing device 60. When the calculated total amount of items G per minute falls outside the second predetermined range, the calculation unit 10C controls the supply amount of items G that will become food before freezing, which is preset in the first item processing device 60, via the control unit 62 of the first item processing device 60 connected via the network N, to change the supply amount. Note that the calculation unit 10C does not have to perform the control when the amount falls outside the second predetermined range as described above. In this modified example 1, the calculation unit 10C also displays a warning on the inspection result screen 80 on the display operation unit 8 when the calculated total amount of items G per minute falls outside the first predetermined range.

[0042] Furthermore, when the calculated total amount of goods G per minute falls outside the first predetermined range, the calculation unit 10C illuminates an abnormality lamp 71 provided on the second goods processing device 70 via the control unit 72 of the second goods processing device 70 connected via the network N. When the calculated total amount of goods G per minute falls outside the second predetermined range, the calculation unit 10C stops the operation of the second goods processing device 70 via the control unit 72 of the second goods processing device 70 connected via the network N. Note that the calculation unit 10C does not have to perform the control described above when the amount falls outside the second predetermined range.

[0043] In the configuration described in this modified example 1, the necessary processing is automatically performed in the first and second item processing devices 60 and 70, which constitute the item processing system 100, without the operator having to obtain the total amount calculated by the calculation unit 10C and take any action on the first item processing device 60 and the second item processing device 70. This reduces the burden on the operator.

[0044] Furthermore, as described above, the calculation unit 10C controls the first item processing device 60, ensuring that a total amount of items G suitable for inspection is supplied to the X-ray inspection device 1, thereby improving the inspection accuracy of the X-ray inspection device 1. In addition, the second item processing device 70 is supplied with a total amount of items G suitable for freezing, resulting in fewer items G that are unsuitable for freezing and improving the yield rate.

[0045] Furthermore, as a further variation of the above modified example 1, the calculation unit 10C may, when the calculated total amount of items G per minute falls outside the first predetermined range, control the supply amount of items G to be food before freezing, which is pre-set in the first item processing device 60, via the control unit 62 of the first item processing device 60 connected via the network N, and stop the operation of the second item processing device 70, via the control unit 72 of the second item processing device 70 connected via the network N.

[0046] (Other variations) In the above modified example 1, a freezing apparatus was used as an example to describe the second article processing apparatus 70, which is located downstream of the X-ray inspection apparatus 1 and connected to the calculation unit 10C of the X-ray inspection apparatus 1. However, it may also be a combination weighing apparatus, various inspection apparatuses, etc. Even in this case, if the calculated total amount of articles G per minute falls outside the first predetermined range or the second predetermined range, the calculation unit 10C may appropriately control the combination weighing apparatus or various inspection apparatuses, etc.

[0047] Instead of the first item processing device 60 in the above modified example, a first work area may be provided in the area where the first item processing device 60 is located, and a second work area may be provided in the area where the second item processing device 70 is located. In this case, the worker can monitor the inspection results of the items G being inspected by the X-ray inspection device 1, and monitor the total amount of items G displayed on the display operation unit 8 of the X-ray inspection device 1, thereby arranging personnel in the first area so that the amount supplied to the second area is an appropriate total amount.

[0048] In the above embodiments and modifications, an example was given in which the calculation unit 10C of the X-ray inspection apparatus 1 controls the first article processing apparatus 60 and / or the second article processing apparatus 70. However, a control device configured separately from the X-ray inspection apparatus 1 may also control the first article processing apparatus 60 and / or the second article processing apparatus 70. [Explanation of symbols]

[0049] 1...X-ray inspection device, 2...Device body, 5...Transport unit, 6...X-ray irradiation unit, 7...X-ray detection unit, 8...Display operation unit, 10...Control unit, 10A...Image generation unit, 10B...Inspection unit, 10C...Calculation unit, 60...First item processing unit, 70...Second item processing unit, 80...Inspection result screen, 85...Display area, 100...Item processing system, G...Item, U...Unit image.

Claims

1. A conveying unit for transporting goods, An X-ray irradiation unit that irradiates the article being transported by the transport unit with X-rays, An X-ray detection unit for detecting the X-rays that have passed through the aforementioned article, An image generation unit generates an X-ray transmission image based on the detection result from the X-ray detection unit, An X-ray inspection apparatus comprising: an X-ray transmission image that performs image processing on the X-ray transmission image to identify the region of an article, and a calculation unit that calculates the total amount of articles to be transported per predetermined time by the transport unit based on the pixel values ​​of the pixels within the identified region of the article.

2. The system further includes a display unit for showing the total amount, The X-ray inspection apparatus according to claim 1, wherein the calculation unit causes the display unit to display a warning when the total amount falls outside a first predetermined range which includes a first upper limit and a first lower limit that have been stored in advance.

3. The X-ray inspection apparatus according to claim 2, wherein when the total amount falls outside a second predetermined range which includes a second upper limit value greater than the first upper limit value and a second lower limit value less than the first lower limit value, the calculation unit causes an article processing device provided upstream and / or downstream of the X-ray inspection apparatus to perform error processing on the article.

4. An X-ray inspection apparatus according to claim 2 or 3, The system includes an article supply device as one of the article processing devices for supplying the article to the X-ray inspection apparatus, The calculation unit controls the article supplying device to change the article supplying amount, which is pre-set, when the total amount falls outside the first predetermined range, thus forming an article processing system.

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