JP2006058134A - X-ray inspection device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an X-ray inspection device for detecting the occurrence of a stay of an article with higher accuracy than in the past. <P>SOLUTION: In this X-ray inspection device 10, a control computer 20 determines whether the stay of a conveyed article G in a shield box 11 has occurred or not based on the detection timing of the article G by sensors 17a, 17b, 18a and 18b, disposed on carry-in and carry-out openings 11a and 11b, and by an X-ray line sensor 14. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an X-ray inspection apparatus that inspects an article based on the amount of transmitted light by irradiating the article with X-rays.

  Conventionally, in the production line of products such as food, in order to prevent the defective product from being shipped when foreign matter is mixed into the product or the product is cracked or broken, the product has failed using an X-ray inspection device. Inspection is being conducted. In this X-ray inspection apparatus, X-rays are irradiated to an object to be inspected continuously conveyed by a conveyer, the X-ray transmission state is detected by an X-ray light receiving unit, and foreign matter is detected in the object to be inspected. It is determined whether there is no contamination, whether the inspection object is cracked or missing, or whether the quantity of unit contents in the inspection object is insufficient. Moreover, the X-ray inspection apparatus may perform an inspection for counting the number of unit contents in the inspection object.

Among such X-ray inspection apparatuses, there is an apparatus that performs stay detection using a line sensor for X-ray detection in order to detect occurrence of stay of an article during conveyance (see Patent Document 1).
JP 2003-121388 A (published April 23, 2003) JP 2002-181735 A (published on June 26, 2002)

However, the conventional X-ray inspection apparatus has the following problems.
That is, in the X-ray inspection apparatus disclosed in the above publication, the stagnation of the article is detected when there is no change in the detection signal in the line sensor. For this reason, when stagnation occurs at a position from the downstream side of the line sensor to the carry-out port, this cannot be detected as stagnation, so there is a possibility that highly accurate stagnation detection cannot be performed.

  An object of the present invention is to provide an X-ray inspection apparatus capable of detecting the occurrence of stagnation of articles with higher accuracy than before.

  An X-ray inspection apparatus according to a first aspect of the present invention is an X-ray inspection apparatus that inspects an article by irradiating an article conveyed through a housing with X-rays and detecting the amount of transmission. An article detection unit and a determination unit are provided. The plurality of article detection units are arranged along the article conveyance path and detect the passage of the article. The determination unit includes, among the plurality of article detection units, a timing at which an article is detected by the first article detection unit arranged on the upstream side in the conveyance path, and a second article detection arranged on the downstream side of the first article detection unit. The presence / absence of the stay of the article is determined based on the timing at which the article is detected in the section.

Here, the presence or absence of the occurrence of the stagnation of the article is determined based on the timing at which the article is detected in the article detection unit arranged in plural along the article conveyance path.
For example, when the first article detection unit is arranged at the carry-in port in the housing and the second article detection unit is arranged at the carry-out port in the housing, the timing at which the article conveyed by the first article detection unit is detected Article passage time calculated from the detection timing of the article conveyed in the second article detector, and passage calculated from the article conveyance speed and the distance between the first article detector and the second article detector. Compare the predicted time.

Here, when the passage time and the predicted passage time are within a predetermined error range, the determination unit determines that the conveyance of the article is normal. On the other hand, when the passage time and the predicted passage time are not within a predetermined error range, the determination unit determines this as occurrence of stagnation of the article.
In this way, by determining the presence / absence of article retention based on the detection timing in the article detection units arranged in a plurality along the conveyance path, the presence / absence of article retention can be determined based on only the detection result in one article detection unit. Compared with the conventional X-ray inspection apparatus for determining, it is possible to detect the conveyance stay of the article with high accuracy.

An X-ray inspection apparatus according to a second invention is the X-ray inspection apparatus according to the first invention, wherein the determination unit includes an article conveyance speed and a distance between the first article detection unit and the second article detection unit. The predicted passage time calculated based on the above and the passage time calculated based on the detection timing in the first and second article detection units are compared to determine the presence or absence of the article.
Here, the article retention is performed by comparing the time calculated based on the detection timing in the first / second article detection unit, the conveyance speed of the article and the distance between the first / second article detection unit, respectively. The presence or absence of occurrence is determined.

Accordingly, it is possible to easily determine whether or not an article is staying by detecting an article in an article detection unit arranged in a plurality along the conveyance path.
An X-ray inspection apparatus according to a third aspect of the present invention is the X-ray inspection apparatus according to the first or second aspect of the present invention, wherein the determination unit passes the actual article in the first article detection unit or the second article detection unit. The presence / absence of article retention is determined by comparing the time, the article transit time in each article detection unit calculated based on the article conveyance speed and the article size.

Here, in each article detection unit, the article detection time is compared with the passage time calculated based on the conveyance speed and the article size to determine whether or not the article stays.
Thereby, even when an article stays in an individual article detection unit and continues to be detected, it can be easily determined as an article transport stay.
An X-ray inspection apparatus according to a fourth aspect of the present invention is the X-ray inspection apparatus according to any one of the first to third aspects of the present invention, wherein the first article detection unit carries in an article formed in the casing. Placed in the mouth.

Here, the 1st article | item detection part is arrange | positioned in the carrying-in port formed in the housing | casing.
Thereby, it is possible to determine the occurrence of stagnation in the housing in which the articles are likely to stay with reference to the detection timing of the articles in the first article detection unit arranged at the carry-in port corresponding to the most upstream side of the casing. it can.
An X-ray inspection apparatus according to a fifth aspect of the present invention is the X-ray inspection apparatus according to any one of the first to fourth aspects of the present invention, wherein the second article detection unit carries the article formed in the housing. Located at the exit.

Here, the 2nd goods detection part is arrange | positioned in the carrying-out port formed in the housing | casing.
Thereby, it is possible to determine the occurrence of stagnation in the housing in which the articles are likely to stay with reference to the detection timing of the articles in the second article detection unit arranged at the carry-out port corresponding to the most downstream side of the casing. it can.
An X-ray inspection apparatus according to a sixth invention is the X-ray inspection apparatus according to any one of the first to fifth inventions, wherein the first article detection unit or the second article detection unit In order to detect X-rays that are irradiated and transmitted, the line sensor is disposed inside the housing.

Here, a line sensor for X-ray detection that has passed through the article is used as the article detection unit.
Accordingly, it is possible to easily determine whether or not the stagnation of the article has occurred based on the detection timing of the article in the line sensor provided in the housing and the detection timing of the article in the other article detection unit. Further, since the line sensor is arranged in the housing, it can be detected as soon as the article stays.

An X-ray inspection apparatus according to a seventh aspect of the present invention is the X-ray inspection apparatus according to any one of the first to sixth aspects of the present invention, wherein the X-ray irradiation amount when the determination unit determines that the article is stagnant. Is further provided with a control unit that controls the amount to be equal to or less than a predetermined amount.
Here, the control unit controls the X-ray irradiation amount to be a predetermined amount or less, for example, the X-ray irradiation amount becomes 0 when the article stays in the housing or the like.

Thereby, it is possible to prevent a large amount of X-rays from being irradiated to the staying article. Furthermore, even when an operator puts his / her hand into the casing in order to remove the articles staying in the casing, it is possible to prevent the operator from being exposed and to ensure safety.
An X-ray inspection apparatus according to an eighth aspect of the present invention is the X-ray inspection apparatus according to any one of the first to seventh aspects, wherein the X-ray inspection apparatus is disposed at an entrance and an exit of an article formed in the housing. And a shielding curtain for preventing X-rays from leaking to the outside of the housing.

Here, shielding curtains for preventing X-ray leakage are provided at the carry-in and carry-out ports formed in the housing.
Usually, such a shielding curtain is formed of lead because it is necessary to prohibit the transmission of X-rays. For this reason, when a relatively lightweight article passes through the carry-in port or the carry-out port, the weight of the curtain itself hinders the conveyance of the product and may cause stagnation.

  Therefore, in the X-ray inspection apparatus of the present invention, a plurality of article detection units are arranged along the conveyance path including the housing, and the presence or absence of the stay is determined in accordance with the timing at which the article detection unit detects the article. As a result, even if a relatively lightweight article that is prone to stay due to the shielding curtain is an object to be inspected, it is possible to detect the stay as soon as the stay occurs, thus minimizing damage caused by stay. Can do.

  According to the X-ray inspection apparatus of the present invention, the detection of the conveyance and retention of articles is improved compared to the conventional X-ray inspection apparatus that determines the presence or absence of article retention based only on the detection result in one article detection unit. It becomes possible to carry out with accuracy.

An X-ray inspection apparatus according to an embodiment of the present invention will be described below with reference to FIGS.
[Configuration of X-ray inspection system as a whole]
As shown in FIG. 1, the X-ray inspection apparatus 10 of the present embodiment is one of apparatuses that perform quality inspection in a production line for products such as food. The X-ray inspection apparatus 10 irradiates X-rays to products that are continuously conveyed, and inspects whether or not foreign substances are mixed in the products based on the X-ray dose that has passed through the products.

  As shown in FIG. 2, the product G that is the inspection object of the X-ray inspection apparatus 10 is carried to the X-ray inspection apparatus 10 by the front conveyor 60. The product G is determined by the X-ray inspection apparatus 10 for the presence or absence of contamination. The determination result in the X-ray inspection apparatus 10 is transmitted to a distribution mechanism 70 disposed on the downstream side of the X-ray inspection apparatus 10. The distribution mechanism 70 sends the product G to the regular line conveyor 80 as it is when the product G is determined to be a non-defective product in the X-ray inspection apparatus 10. On the other hand, when the product G is determined to be a defective product in the X-ray inspection apparatus 10, the arm 70a having the downstream end as a rotation shaft rotates so as to block the conveyance path. As a result, the product G determined to be defective can be collected by the defective product collection box 90 arranged at a position off the conveyance path.

  As shown in FIG. 1, the X-ray inspection apparatus 10 mainly includes a shield box (housing) 11, a conveyor (conveying unit) 12, a shielding noren (shielding curtain) 16, and a monitor (display device) with a touch panel function. 26). And inside, as shown in FIG. 3, the conveyor 12, X-ray irradiator (irradiation part) 13, X-ray line sensor (article detection part, 1st, 2nd article detection part) 14, sensor (article detection) Section, first article detection section) 17a, 17b, sensors (article detection section, second article detection section) 18a, 18b (see FIGS. 4 to 6), and control computer (control section, determination section) 20 shown in FIG. It has.

[Shield box]
The shield box 11 has a loading / unloading port 11a and a loading / unloading port 11b for loading and unloading the product on both the entrance side and the exit side of the product G. In this shield box 11, a conveyor 12, an X-ray irradiator 13, an X-ray line sensor 14, a control computer (control unit, determination unit) 20 (see FIG. 4) and the like are accommodated.

Further, as shown in FIG. 1, the carry-in port 11 a and the carry-out port 11 b are closed by a shielding nore (shielding curtain) 16 in order to prevent leakage of X-rays to the outside of the shield box 11. This shielding nolen 16 has a rubber nolene portion containing lead, and is pushed away by the product when the product is carried in and out.
Further, in addition to the monitor 26, a key insertion slot and a power switch are arranged on the upper front portion of the shield box 11.

〔Conveyor〕
The conveyor 12 conveys commodities within the shield box 11, and is driven by a conveyor motor 12f included in the control block shown in FIG. The conveyance speed of the conveyor 12 is finely controlled by the inverter control of the conveyor motor 12f by the control computer 20 so as to be the set speed input by the operator.

  Moreover, the conveyor 12 has the conveyor belt 12a, the conveyor frame 12b, the opening part 12c, and the conveyor guide (guide part) 12d, as shown in FIG. The conveyor 12 is attached to the shield box 11 in a removable state. As a result, even when food or the like is handled as an inspection target, the conveyor can be removed and frequently washed to keep the inside of the shield box 11 clean.

The conveyor belt 12a is an endless belt, and is supported by the conveyor frame 12b from the inside of the belt. And the object mounted on the belt is conveyed in a predetermined direction by receiving the driving force of the conveyor motor 12f and rotating.
The conveyor frame 12b supports the conveyor belt 12a from the inside of the endless belt, and has an opening 12c that is long in the direction orthogonal to the conveying direction at a position facing the inner surface of the conveyor belt 12a. ing.

  The opening 12c is formed on a line connecting the X-ray irradiator 13 and the X-ray line sensor 14 in the conveyor frame 12b. In other words, the opening 12c is formed in the X-ray irradiation region from the X-ray irradiator 13 in the conveyor frame 12b. Thereby, the X-ray which permeate | transmitted the goods G permeate | transmits the conveyor belt 12a, and is detected in the X-ray line sensor 14 without being shielded by the conveyor frame 12b.

  The conveyor guide 12d is provided on both sides of the conveyor belt 12a that forms the conveyance path for the product G, and guides the article so that the article moving on the conveyor 12 does not deviate from the conveyance path. In other words, as shown in FIG. 3, the conveyor guide 12 d crosses the X-ray line sensor 14 disposed below the conveyor 12 and intersects the X-ray line sensor 14 in a plan view. These are arranged in the irradiation region of the X-rays irradiated from the X-ray irradiator 13. Furthermore, the conveyor guide 12d is attached to the shield box 11 together with the conveyor 12 in a detachable state. For this reason, even when food or the like is handled as an inspection target, the inside of the shield box 11 can always be kept clean by removing and cleaning the entire conveyor 12.

[X-ray irradiator]
As shown in FIG. 3, the X-ray irradiator 13 is disposed above the conveyor 12 and is disposed below the conveyor 12 through an opening 12c formed in the conveyor frame 12b. (Light receiving part, line sensor) X-rays are irradiated in a fan shape toward the light 14 (see the hatched part in FIG. 3).

In addition, the X-rays irradiated from the X-ray irradiator 13 are irradiated over a region including the pixels 14a at both ends of the X-ray line sensor 14, as shown in FIG.
[X-ray line sensor]
The X-ray line sensor 14 is disposed below the conveyor 12 and detects X-rays transmitted through the product G and the conveyor belt 12a. The X-ray line sensor 14 includes a plurality of pixels arranged horizontally in a straight line in a direction orthogonal to the conveying direction by the conveyor 12.

  Further, the X-ray line sensor 14 detects the timing at which the product G has passed over the X-ray line sensor 14 in addition to the detection of the X-rays transmitted through the product G to be inspected. The detected passage timing (ON / OFF signal) of the product G is transmitted from the X-ray line sensor 14 to the control computer 20 and used as a reference for determining the stay of the product G, which will be described later.

〔monitor〕
The monitor 26 is a full dot display liquid crystal display. Further, the monitor 26 has a touch panel function, and displays a screen that prompts input of parameters relating to initial setting and defect determination. In addition, the monitor 26 displays the inspection result of the product G, a warning when the conveyance stay of the product G occurs, and the like.

[Control computer]
As shown in FIG. 4, the control computer 20 includes a CPU 21 and a ROM 22, a RAM 23, and a CF (compact flash: storage unit) 25 as main storage units controlled by the CPU 21. In the CF 25, the stay determination reference information 25 a such as the passage timing of the product G for determining whether or not an abnormality such as the stay of the product G in the shield box 11 described later has occurred, the transport speed of the conveyor 12, etc. An inspection result log file 25b for storing inspection images and inspection results is stored.

The control computer 20 also includes a display control circuit that controls data display on the monitor 26, a key input circuit that captures key input data from the touch panel of the monitor 26, and an I / O for controlling data printing in a printer (not shown). USB 24 as an external input terminal is provided.
Storage units such as the CPU 21, ROM 22, RAM 23, and CF 25 are connected to each other via bus lines such as an address bus and a data bus.

The control computer 20 is connected to a conveyor motor 12f, a rotary encoder 12g, an X-ray irradiator 13, an X-ray line sensor 14, and the like.
The rotary encoder 12g is attached to the conveyor motor 12f, detects the conveying speed of the conveyor 12, and transmits it to the control computer 20.
The X-ray irradiator 13 is controlled by the control computer 20 to control X-ray irradiation timing, X-ray irradiation amount, X-ray irradiation prohibition, and the like.

The X-ray line sensor 14 transmits a signal value based on the X-ray dose detected in each pixel to the control computer 20.
The sensors 17a and 17b and the sensors 18a and 18b are composed of a pair of light-emitting elements and light-receiving elements that are arranged with a conveyor interposed therebetween in order to detect the passage of the product G that is an object to be inspected. The transmitted signal is transmitted to the control computer 20.

[Sensor]
As shown in FIGS. 5 and 6, the sensors 17a and 17b have a pair of light emitting / receiving elements 17aa and 17ab and light receiving and emitting elements 17ba and 17bb arranged on the carry-in entrance 11a side of the shield box 11. The sensors 17a and 17b receive light emitted from the light emitting elements 17aa and 17ba at the light receiving elements 17ab and 17bb when the operation is started. And if the goods G conveyed by the conveyor 12 pass the predetermined detection position in the carry-in entrance 11a, the light emitted from the light emitting elements 17aa and 17ba cannot be detected by the light receiving elements 17ab and 17bb. For this reason, the control computer 20 detects the non-light receiving state in the light receiving elements 17ab and 17bb as the passage of the commodity G in the carry-in entrance 11a.

  The sensors 18a, 18b have a pair of light emitting / receiving elements 18aa, 18ab and light receiving / emitting elements 18ba, 18bb arranged on the carry-out port 11b side of the shield box 11. Similar to the sensors 17a and 17b, the sensors 18a and 18b receive light emitted from the light emitting elements 18aa and 18ba at the light receiving elements 18ab and 18bb at the start of operation. And if the goods G pass the predetermined detection position in the carry-out port 11b, the light irradiated from the light emitting elements 18aa and 18ba cannot be detected by the light receiving elements 18ab and 18bb. For this reason, the control computer 20 detects the non-light receiving state in the light receiving elements 18ab and 18bb as the passage of the commodity G in the carry-out port 11b.

  The sensors 17a to 18b transmit ON / OFF signals indicating the light receiving states of the light receiving elements 17ab, 17bb, 18ab, and 18bb to the control computer 20 described above. The control computer 20 stores the ON / OFF signal received from the sensors 17a to 18b in the CF 25. Further, the control computer 20 detects the passing timing of each commodity G on the carry-in port 11a, the X-ray line sensor 14, and the carry-out port 11b based on the ON / OFF signal stored in the CF 25. And the passage time of the goods G between the article | item detection parts (sensors 17a-18b, X-ray line sensor 14) calculated from these passage timings is compared with the passage prediction time previously memorize | stored in CF25. Then, it is determined whether or not an abnormality such as retention of the product G in the shield box 11 has occurred. Note that the determination of the presence or absence of stagnation by the control computer 20 will be described in detail later.

  In addition, the sensor 17a has the light emitting element 17aa and the light receiving element 17ab disposed on both sides of the conveyor 12 on the carry-in entrance 11a side and at a height position where the product G conveyed by the conveyor 12 can be detected. The sensor 18a arranges the light emitting element 18aa and the light receiving element 18ab at the height positions on both sides of the conveyor 12 on the side of the carry-out port 11b where the product G can be detected. On the other hand, the sensor 17b arranges the light emitting element 17ba and the light receiving element 17bb on both sides of the conveyor 12 on the carry-in entrance 11a side, at a height position where the product G can be detected and higher than the sensor 17a. . The sensor 18b has a light emitting element 18ba and a light receiving element 18bb arranged on both sides of the conveyor 12 on the carry-out port 11b side and at a position higher than the sensor 18a.

  The light irradiated from each light emitting element 17aa, 17ba, 18aa, 18ba in parallel to the transport surface of the conveyor 12 is received by the corresponding light receiving elements 17ab, 17bb, 18ab, 18bb arranged on the opposite side across the conveyor 12. Each is detected. And the light reception state in light receiving element 17ab-18bb is transmitted to the control computer 20 (refer FIG. 4) as an ON / OFF signal. Note that an ON signal is transmitted when the light receiving elements 17ab, 17bb, 18ab, and 18bb are in a light receiving state, and an OFF signal is transmitted when the light receiving element is not receiving light.

[Detection of stay by this X-ray inspection system]
In the X-ray inspection apparatus 10 of the present embodiment, the occurrence of an abnormality such as a conveyance stay of the product G in the shield box 11 is detected using the configuration described above. Such conveyance stay of the product G occurs, for example, when the product G is caught on the shielding nol 16 or when the product G is caught on the conveyor guide 12d or the like. In particular, when the product G is light, when passing the lead-containing shielding nolen 16 provided so as to block the carry-in entrance 11a and the carry-out exit 11b in order to shield X-rays, the noren portion is pushed away. It is easy to stay.

  As a specific detection method, the estimated passing time of the product G between the article detection units calculated from the conveyance speed of the conveyor 12 and the distance between the article detection units (sensors 17a to 18b, X-ray line sensor 14). And the actual passage time of the commodity G between the article detection units calculated from the detection timing detected in each article detection unit, and the product G when the actual passage time is longer than the predicted passage time Is determined to be staying in transit. When this determination is made, it is not determined that the stay has not occurred only when the predicted passage time and the passage time completely match. What is necessary is just to judge.

As the article detection unit, the above-described sensors 17a, 17b, 18a, 18b and the X-ray line sensor 14 can be used. For example, when the sensors 17a and 17b are used as the first article detection unit and the X-ray line sensor 14 is used as the second article detection unit, the determination is performed in the following procedure.
First, the article detection by the X-ray line sensor 14 from the article detection position by the sensors 17a and 17b, based on the passage timing of the commodity G detected by the sensors 17a and 17b and the detection timing of the commodity G detected by the X-ray line sensor 14. The actual passing time t1 to the position (see FIG. 5) is calculated. On the other hand, in the CF 25, sensors 17a, 17b to X-ray lines calculated based on the distance between the article detection position by the sensors 17a, 17b and the article detection position by the X-ray line sensor 14 and the conveying speed of the conveyor 12. The estimated passage time to the sensor 14 is stored. Here, when the estimated passage time is compared with the actual passage time, the actual passage time is longer than the passage prediction time, or the product G is not detected by the X-ray line sensor 14 even when the passage prediction time is reached. The control computer 20 determines that the product G is staying between the sensors 17a and 17b and the X-ray line sensor 14 and causes the monitor 26 to display a warning of occurrence of abnormality on the screen. Control is performed so as to stop the X-ray irradiation from the X-ray irradiator 13.

In addition, when the conveyance speed by the conveyor 12 changes by a setting change etc., it is necessary to change passage measurement time according to this. For this reason, when there is a change in the conveyance speed by the conveyor 12, the control computer 20 calculates a new estimated passage time based on the changed conveyance speed and stores it in the CF 25.
[Features of this X-ray inspection system]
(1)
In the X-ray inspection apparatus 10 of the present embodiment, the control computer 20 is based on the detection timing of the product G in the sensors 17a17b, 18a, 18b and the X-ray line sensor 14 disposed at the carry-in port 11a, the carry-out port 11b. It is determined whether or not the product G conveyed in the shield box 11 has stayed.

  Specifically, while calculating the passage time between each article detection part based on the detection timing by the some article detection part arrange | positioned along the conveyance path, the conveyance speed by the conveyor 12 and the distance between each article detection part Are compared with the estimated passage time of the product G calculated from the above. Here, when the actual passage time is longer than the predicted passage time, it is determined that the commodity G is staying.

  Thus, between the carry-in port 11a (sensors 17a and 17b) and the X-ray line sensor 14, between the X-ray line sensor 14 and the carry-out port 11b (sensors 18a and 18b), and the carry-in port 11a (sensors 17a and 17b) and the carry-out port. It is possible to easily determine whether or not the conveyance of the product G has occurred between 11b (sensors 18a and 18b). As a result, it is possible to determine the presence or absence of stagnation with higher accuracy compared to the conventional X-ray inspection apparatus that determines that stagnation occurs when detection by one sensor is not detected for a predetermined period.

(2)
In the X-ray inspection apparatus 10 of the present embodiment, the control computer 20 is based on the detection timing in the sensors 17a and 17b and the detection timing in the X-ray line sensor 14 disposed downstream of the sensors 17a and 17b. The passing time between the sensors 17a, 17b and the X-ray line sensor 14 is calculated. The control computer 20 passes the product G between the sensors 17a, 17b and the X-ray line sensor 14 based on the distance between the sensors 17a, 17b and the X-ray line sensor 14 and the conveyance speed of the product G by the conveyor 12. Calculate the predicted time.

Thereby, it is possible to easily determine whether or not the product G stays between the sensors 17a and 17b to the X-ray line sensor 14 only by comparing the actual product G transit time and the estimated passage time. .
(3)
In the X-ray inspection apparatus 10 of this embodiment, sensors 17a and 17b as first article detection units are provided on the carry-in entrance 11a side.

Thereby, the presence or absence of the stay between the carry-in port 11a and the X-ray line sensor 14 and the presence or absence of the stay between the carry-in port 11a and the carry-out port 11b can be easily determined by the above method.
(4)
In the X-ray inspection apparatus 10 of this embodiment, sensors 18a and 18b as second article detection units are provided on the carry-out port 11b side.

Thereby, the presence or absence of the stay between X-ray line sensor 14 and carry-out port 11b and the presence or absence of the stay between carry-in port 11a and carry-out port 11b can be easily determined by the above method.
(5)
In the X-ray inspection apparatus 10 of the present embodiment, the X-ray line sensor 14 is used as the first article detection unit or the second article detection unit.

  For example, in the case where the X-ray line sensor 14 is used as the second article detection unit, it is easy to determine whether or not the conveyance of the product G has occurred between the sensors 17a and 17b arranged at the carry-in entrance 11a. Can be determined. On the other hand, when the X-ray line sensor 14 is used as the first article detection unit, it is easy to check whether or not the conveyance of the product G has occurred between the sensors 18a and 18b arranged at the X-ray line sensor 14 to the carry-out port 11b. Can be determined.

(6)
In the X-ray inspection apparatus 10 according to the present embodiment, when the control computer 20 determines that the product G is staying in the shield box 11, the X-ray irradiation from the X-ray irradiator 13 is stopped. Controlled.
This prevents the product G from staying in the shield box 11 for a longer time than usual due to staying from being continuously irradiated with more X-rays than necessary, and prevents the product G from accumulating X-rays. Can do. Furthermore, since the product G staying in the shield box 11 when the stagnation occurs is eliminated, it is safe to avoid exposure of the worker by reducing the X-ray irradiation amount to zero. A highly reliable X-ray inspection apparatus 10 can be obtained.

(7)
In the X-ray inspection apparatus 10 of the present embodiment, a shielding nole 16 for preventing X-rays from leaking to the outside of the shield box 11 is attached to the carry-in port 11a and the carry-out port 11b.
Usually, the shielding nolen 16 for shielding X-rays contains lead in order to prevent transmission of X-rays and is heavy. For this reason, when the product G is lightweight, the product G cannot pass through the noren due to the weight of the shielding nolen 16 and is likely to stay.

Therefore, in the X-ray inspection apparatus 10 according to the present embodiment, it is possible to determine whether or not the product stays due to the product trapped on the shielding nolen 16. Can be minimized.
[Other Embodiments]
As mentioned above, although one Embodiment of this invention was described, this invention is not limited to the said embodiment, A various change is possible in the range which does not deviate from the summary of invention.

(A)
In the above-described embodiment, an example in which the sensors 17a and 17b are used as the first article detection unit and the X-ray line sensor 14 is used as the second article detection unit has been described. However, the present invention is not limited to this.
For example, when the X-ray line sensor 14 is used as the first article detection unit, and the sensors 18a and 18b are used as the second article detection unit, the sensors 17a and 17b are used as the first article detection unit, and the sensor 18a is used as the second article detection unit. 18b may be used. Even in this case, similarly to the above, it is possible to easily determine the presence or absence of conveyance of the product G by comparing the actual passage times t2 and t3 (see FIG. 5) with the predicted passage time.

(B)
In the above embodiment, an example in which presence / absence of stagnation is determined based on the detection timing in the sensors 17a and 17b as the first article detection unit and the detection timing in the X-ray line sensor 14 as the second article detection unit. And explained. However, the present invention is not limited to this.

  For example, the presence / absence of stay may be determined based on the detection time of the product G in each article detection unit. In this case, the expected detection time of the product G when there is no stagnation is calculated from the transport speed of the product G by the conveyor 12 and the size in the transport direction of the product G, and stored in the CF 25. When the actual detection time is longer than the expected detection time by comparing the time detected by the sensors 17a and 17b and the X-ray line sensor 14 with the predicted detection time stored in the CF 25. In this case, it is possible to obtain the same effect as described above by determining that the stagnation has occurred. In addition, by performing the determination using the detection time in each article detection unit as described above, it is possible to detect not only the stay of the product G but also the care at the carry-in port 11a or the carry-out port 11b.

(C)
In the above embodiment, an example has been described in which the control computer 20 calculates the estimated passage time corresponding to the new transport speed each time the transport speed is changed by the conveyor 12. However, the present invention is not limited to this.
For example, a table relating to the estimated passage time corresponding to the conveyance speed by the conveyor 12 is stored in the CF 25, and when the conveyance speed is changed, the presence or absence of occurrence of stagnation is detected using the corresponding estimated passage time from the table. You may judge.

Such a table relating to the predicted passage time can be easily created when the distance between the article detection units is unchanged. Further, in the case of an X-ray inspection apparatus in which the distance between each article detection unit changes, the estimated passage time may be extracted using a plurality of tables created for each distance.
(D)
In the embodiment described above, an example in which the sensors 17a and 17b and the sensors 18a and 18b are arranged in both the carry-in port 11a and the carry-out port 11b has been described. However, the present invention is not limited to this.

For example, even when any one of the carry-in port 11a and the carry-out port 11b is equipped with a sensor, it is possible to determine whether or not the stagnation has occurred from the detection result of the sensor and the detection result of the X-ray line sensor 14. The same effects as described above can be obtained.
(E)
In the above embodiment, an example in which two sensors 17a and 17b and sensors 18a and 18b are arranged at the carry-in port 11a and the carry-out port 11b has been described. However, the present invention is not limited to this.

For example, one sensor may be arranged in at least one of the carry-in port 11a and the carry-out port 11b.
However, it is more preferable to arrange a plurality of sensors at the carry-in port 11a and the carry-out port 11b as in the present embodiment, in addition to the retention of the product G, the maintenance in the shield box can be detected.

(F)
In the above-described embodiment, an example in which a pair of light emitting / receiving elements is used as the sensors 17a and 17b and the sensors 18a and 18b has been described. However, the present invention is not limited to this.
For example, a reflective photoelectric tube or a capacitive sensor can be used as an alternative to a set of light emitting and receiving elements. Among these, when a capacitive sensor is used, it can be detected by utilizing the property that the dielectric constant changes when a human hand enters the detection position of the sensor. There is an advantage that it is wider than the sensor to irradiate.

(G)
In the said embodiment, when the control computer 20 determined with generation | occurrence | production of the stay of the goods G, the X-ray irradiation amount from the X-ray irradiator 13 was set to the example and demonstrated. However, the present invention is not limited to this.
For example, instead of setting the X-ray irradiation amount to 0, the control computer 20 may control the X-ray irradiator 13 so as to be a predetermined X-ray dose or less. Even in this case, it can be avoided that a large amount of X-rays are irradiated to the product G staying in the shield box 11 and X-rays are accumulated in the product G.

  The X-ray inspection apparatus of the present invention has the effect of being able to detect the stay of an article with higher accuracy than before, and thus can be widely applied to various inspection instruments that inspect while conveying an article. .

1 is an external perspective view of an X-ray inspection apparatus according to an embodiment of the present invention. The figure which shows the structure before and behind an X-ray inspection apparatus. The simple block diagram inside the shield box of a X-ray inspection apparatus. The block block diagram of a control computer. The side view which shows the inside of a shield box. The top view which shows the inside of a shield box.

Explanation of symbols

10 X-ray inspection equipment 11 Shield box (housing)
11a Carry-in port 11b Carry-out port 12 Conveyor 12a Conveyor belt 12b Conveyor frame 12c Opening part 12d Conveyor guide 12f Conveyor motor 12g Rotary encoder 13 X-ray irradiator (irradiation part)
14 X-ray line sensor (article detection unit, first and second article detection unit)
16 Shielding Noren 17a, 17b Sensor (article detection unit, first article detection unit)
18a, 18b sensor (article detection unit, second article detection unit)
20 control computer 21 CPU
22 ROM (storage unit)
23 RAM (storage unit)
24 USB (external connection terminal)
25 CF (compact flash, storage unit)
26 Monitor G Product t1-t3 Passing time

Claims (8)

An X-ray inspection apparatus that inspects the article by irradiating the article conveyed in the housing with X-rays, detecting the amount of transmission thereof,
A plurality of article detectors arranged along a conveyance path of the article, and detecting the passage of the article;
Among the plurality of article detection units, a timing at which the article is detected in the first article detection unit arranged on the upstream side in the conveyance path, and a second article detection arranged on the downstream side of the first article detection unit. A determination unit that determines the presence or absence of occurrence of retention of the article based on the timing at which the article is detected in the unit;
X-ray inspection apparatus. The determination unit
A predicted passage time calculated based on the conveyance speed of the article and the distance between the first article detection unit and the second article detection unit;
A transit time calculated based on the detection timing in the first and second article detection units;
To determine whether there is an article retention,
The X-ray inspection apparatus according to claim 1. The determination unit is an individual article detection unit that is calculated based on the actual passage time of the article in the first article detection unit or the second article detection unit, the conveyance speed of the article, and the size of the article. Comparing the passage time of the article in to determine the presence or absence of the article retention,
The X-ray inspection apparatus according to claim 1 or 2. The first article detection unit is disposed at a carry-in port of the article formed in the housing.
The X-ray inspection apparatus according to any one of claims 1 to 3. The second article detection unit is disposed at a carry-out port of the article formed in the housing.
The X-ray inspection apparatus according to any one of claims 1 to 4. The first article detection unit or the second article detection unit is a line sensor disposed inside the housing in order to detect X-rays that are irradiated and transmitted through the article.
The X-ray inspection apparatus according to any one of claims 1 to 5. When the determination unit determines that the article is stagnant, the control unit further includes a control unit that controls the X-ray irradiation amount to be a predetermined amount or less.
The X-ray inspection apparatus according to any one of claims 1 to 6. Arranged at the carry-in and carry-out ports of the article formed in the housing, further comprising a shielding curtain for preventing the X-ray from leaking outside the housing;
The X-ray inspection apparatus according to any one of claims 1 to 7.

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