JP4737427B2 - Inline X-ray fluoroscope - Google Patents

Description

  According to the present invention, an inspection object is sequentially passed between an X-ray source and an X-ray line sensor arranged opposite to each other by a conveyor, and X-ray fluoroscopy of the inspection object is performed using X-ray transmission data obtained at that time. More particularly, the present invention relates to an inline X-ray fluoroscopy device that displays an image on a display, and more specifically, an inline X-ray fluoroscopy device that visually checks an X-ray fluoroscopic image of an inspection object displayed on the display to determine whether the inspection is acceptable. About.

  Using the X-ray transmission data obtained when the inspection object is sequentially conveyed by the conveyor between the X-ray source and the X-ray line sensor and each inspection object passes between the X-ray source and the X-ray line sensor. An apparatus for displaying an X-ray fluoroscopic image of an inspection object on a display is known.

In this type of fluoroscopic apparatus, as a method of forming a fluoroscopic image, conventionally, a method in which the fluoroscopic image moves on the screen in synchronization with the conveyance direction of the object to be inspected, that is, the fluoroscopic image is animated with respect to the conveyance direction of the conveyor. The X-ray transmission data is stored in the memory until the X-ray transmission data capable of displaying the entire fluoroscopic image of the inspection object and the X-ray transmission data that can display the entire fluoroscopic image of the inspection object are obtained. There is a method of displaying a still image and switching the display for each frame (one inspection object) (see, for example, Patent Document 2).
JP-A-11-230918 JP 2006-71423 A

  By the way, when inspecting for the presence of dangerous foreign substances in shoes, bags, stuffed animals, futons, clothes, etc. using the inline X-ray fluoroscope as described above, normal products also contain metal parts. In this case, it is difficult to automatically inspect for the presence or absence of foreign matter by image processing of an X-ray fluoroscopic image, that is, automatic inspection. In such a case, the X-ray fluoroscopic image is visually inspected.

  When visual inspection using X-ray fluoroscopic images is performed, it is difficult to find small dangerous objects such as needles and nails in the former conventional in-line X-ray fluoroscopic apparatus that displays the former moving image. Moreover, in order to reliably determine the presence or absence of such a small dangerous article, it is necessary to reduce the conveyor speed, which is not suitable for a product with a large production volume. In addition, in a product that is long in the conveyance direction, only a part of the fluoroscopic image appears at all times, and there is a problem that it is difficult to specify the position of a foreign substance in the product.

  On the other hand, in the latter device that displays still images, it is relatively easy to find small foreign objects such as needles and nails even if the conveying speed by the conveyor is increased as compared to the case of moving image display. Even if the product is long in the transport direction, it is necessary to reduce the display magnification in order to display a perspective image of the entire product on the display screen. In this case, small foreign objects such as needles and nails It will be difficult to find.

  The present invention has been made in view of such a situation, and has a high inspection work efficiency, and even a long product can reliably determine the presence or absence of foreign matter by visual inspection, and the foreign matter in the product. An object of the present invention is to provide an in-line X-ray fluoroscopy device that can easily specify the location.

In order to solve the above-described problems, an in-line X-ray fluoroscopic apparatus of the present invention includes an X-ray source and an X-ray line sensor that are arranged to face each other, and an object to be inspected between the X-ray source and the X-ray line sensor. An X-ray fluoroscopic image of the object to be inspected is constructed by using the conveyer and the X-ray transmission data taken when the object to be inspected passes between the X-ray source and the X-ray line sensor by the conveyor. In an X-ray fluoroscopic apparatus provided with display means for displaying on a display device,
Input means for inputting the length along the conveyance direction of the inspection object, setting means for setting the conveyance speed of the conveyor, the length of the inspection object input by the input means, and the setting means And calculating means for calculating the scan interval of the line sensor so that the object to be inspected fits on the screen of the display device, and the X-ray line sensor is scanned at the calculated scan interval. Control means and detection means for detecting that the object to be inspected has reached between the X-ray source and the X-ray line sensor. The display means starts from the detection signal and the object to be inspected is the X-ray. While passing over the line sensor, X-ray fluoroscopic data from the X-ray line sensor is stored, and an X-ray fluoroscopic image of the inspection object is displayed after the inspection object has passed. Both, each time switching the X-ray fluoroscopic image displayed on the indicator, Ru characterized by that it comprises a notifying means for notifying to that effect.

The present invention displays an X-ray fluoroscopic image of an object to be inspected as a still image, and sets the scan interval of the X-ray line sensor in the direction of conveyance by calculation based on the input direction length and conveyance speed of the object to be inspected. The X-ray fluoroscopic image of a long inspected object will fit within the display screen of the display , and every time the image displayed on the display is switched, a notification to that effect is made to solve the problem. To do.

  That is, the detection means detects that the object to be inspected has been transported to the position where the X-ray source and the X-ray line sensor are arranged, and X-ray transmission data captured by scanning of the X-ray line sensor is completed for one frame. The point that the X-ray fluoroscopic image of the inspection object is displayed as a still image every time is the same as the conventional still image display method described above, but in the present invention, the length of the inspection object in the conveyance direction and the conveyance speed are the same. Accordingly, the scan interval of the X-ray line sensor is changed. The scan interval is an interval in which the X-ray fluoroscopic image of the inspection object is within the display screen.

  Here, in a state where normal display (display with an aspect ratio of 1: 1) is performed, if only the scan interval of the X-ray line sensor is increased, for example, the X-ray fluoroscopic image becomes an image compressed in the transport direction. . In the present invention, the X-ray fluoroscopic image of the inspected object displayed on the display device is changed in the magnification in the conveyance direction by appropriately determining the scan interval according to the conveyance direction length and the conveyance speed. Fit in the display screen.

  According to such a display method, since the fluoroscopic image is a still image, it is easy to find even a small foreign object, and even if the inspection object is long in the transport direction, the image in that direction is compressed. Since the direction orthogonal thereto is performed at a normal magnification, it is easier to determine the presence or absence of foreign matter as compared to reducing the overall display magnification of the fluoroscopic image. And even if the inspection object is long in the transport direction, the entire perspective image is displayed, so that it is easy to specify the position of the foreign object.

Further, X-ray transmission image of the object to be displayed as a still image, not whether the difficulty know whether switched to those after the preceding object to be inspected. Therefore, in the present invention, by, for example, a buzzer or the like each time the switches are X-ray fluoroscopic image you notification to that effect. Thereby , the inspector can surely know that the inspection object has changed.

  According to the present invention, the entire X-ray fluoroscopic image is displayed on a single screen as a still image even for a product that is long in the conveying direction. Therefore, in a visual inspection using the X-ray fluoroscopic image, small foreign matters such as needles and nails are displayed. Even if the object to be inspected is long in the transport direction, the scan interval of the X-ray line sensor is changed by the input of the length, and the fluoroscopic image is compressed in the same direction. Since the entire perspective image is displayed on the container, the position of the foreign object can be easily specified.

In addition , every time the fluoroscopic image of the inspection object changes, the fact is notified, so that the inspector can surely know that the inspection object has changed, and the inspection object that is the object of the visual inspection result The possibility of making mistakes can be eliminated.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a configuration diagram of an embodiment of the present invention, and is a diagram illustrating a schematic diagram showing a mechanical configuration and a block diagram showing a system configuration. FIG. 2 is a diagram of the mechanical configuration of FIG. 1 viewed from the conveyance direction.

  The inspection object W is conveyed by the conveyor 1 in the direction indicated by the arrow in the figure. On the conveyance path by the conveyor 1, the X-ray source 2 and the X-ray line sensor 3 are arrange | positioned facing the vertical direction.

  X-rays from the X-ray source 2 are formed in a fan beam shape by slits (not shown) or the like, and the X-ray line sensor 3 is arranged so that pixels are arranged in the X-ray spreading direction. The X-ray transmission data enters the X-ray line sensor 3 when the inspection object W passes between them. Note that the periphery of the X-ray source 2 and the X-ray line sensor 3 is surrounded by a shield box (not shown).

  A photoelectric switch 4 is provided upstream of the arrangement position of the X-ray source 2 and the X-ray detector 3, and a detection signal is output when the inspection object W passes through the arrangement position of the photoelectric switch 4. Is done. The photoelectric switch 4 is disposed at a position immediately before the tip of the inspection object W reaches between the X-ray source 2 and the X-ray line sensor 3.

  The X-ray line sensor 3 scans in synchronization with the line pulse supplied from the control unit 5 and outputs image data for one line. The image data is stored in one of the two frame memories 7a and 7b via an image data capturing circuit 6 such as a capture board. The frame memories 7a and 7b alternately store frame data as described later under the control of the control unit 5. That is, if the frame data of one inspection object W is stored in, for example, one frame memory 7a, the frame data of the next inspection object W is stored in the other frame memory 7b. Each time a set of frame data is stored in each of the frame memories 7a and 7b, the contents are displayed on the display 9 via the display changeover switch 8 controlled by the control unit 5.

  In addition to the X-ray line sensor 3, the frame memories 7a and 7b, and the display changeover switch 8, the control unit 5 places the conveyor 1 and the X-ray source 2 under control. An operation unit 10 is connected to the control unit 5, and the operation unit 10 can set the conveyance speed by the conveyor 1, and by inputting the length in the conveyance direction of the inspection object W, The scan interval of the X-ray line sensor 3 is automatically set as shown below so that the X-ray fluoroscopic image fits the screen of the display 9 even if the length of the inspection object W in the transport direction is long. The In addition, a buzzer 11 is connected to the control unit 5 for notifying that effect when switching images.

Next, the operation of the above embodiment will be described together with its usage.
While the conveyance speed V by the conveyor 1 is set by operating the operation unit 10, the conveyance direction length L of the inspection object W is input. The control unit 5 calculates the scan interval of the X-ray line sensor 3 using these values V and L. As an example of the calculation method, assuming that an X-ray line sensor 3 having 1024 pixels at a pitch of 0.5 mm is used, and obtaining an image of 1024 × 1024 by the output of the X-ray line sensor 3, When the conveyance speed of the conveyor 1 is 10 m / min and the length of the inspection object in the conveyance direction is 512 mm, the time required for the X-ray fluoroscopic image to fill one screen of the display 9 is defined as a basic time t ₀ . That is,
The basic time t ₀ = (512 [mm] / 1024) / (10000/60) [mm / s] = 3 ms.

From the set transport speed V and the input transport direction length L of the inspection object W, the scan interval t is set to t = (V / 10) × (L / 512) × t _0.
Calculated by A line pulse signal is supplied to the X-ray line sensor 3 at the obtained scan interval t, and scanning is performed for each pulse.

  FIG. 3 shows a time chart representing the operation of the apparatus. When the inspection object W is conveyed by the conveyor 1 and approaches the arrangement position of the X-ray source 1 and the X-ray line sensor 3, first, the photoelectric switch 4 detects the inspection object W and the product passage signal is turned ON. . In FIG. 3, this first inspection object W is represented as a product 0. The controller 5 raises the image capture signal a simultaneously with the rise of the product passage signal. The image capture signal a is a signal for capturing data into the frame memory 7a out of the two frame memories 7a and 7b. The X-ray transmission data for one column obtained by the scanning operation of the X-ray line sensor 3 is sequentially obtained. It is taken into the frame memory 7a. The duration of the image capture signal a is (L / 512) / (V / 10). At the end of the image capture signal a, one frame of data is prepared in the frame memory 7a. An X-ray fluoroscopic image is displayed on the display 9. At this time, a drive signal is issued to the buzzer 11 to sound the buzzer.

  Eventually, when the next inspection object W (product 1) is conveyed by the conveyor 1, the product passing signal based on the output of the photoelectric switch 4 rises and the image capture signal b is raised as described above. This image capture signal b is a signal for capturing data into the frame memory 7b, and data for one column obtained by the scanning operation of the X-ray line sensor 3 is sequentially captured into the frame memory 7b. The duration of the image capture signal b is the same as that of the image capture signal a described above. When the image capture signal b is completed and X-ray transmission data for one frame is prepared, the image stored in the frame memory 7b is stored. The data is displayed on the display 9 through the switch 8 and the buzzer 11 is sounded at the same time.

  The above operation is repeated, and each time the inspection object W conveyed on the conveyor 1 passes through the arrangement positions of the X-ray source 2 and the X-ray line sensor 3, the X-ray fluoroscopic images are sequentially displayed as still images. The buzzer 11 sounds each time the image is switched. In the above embodiment, the point to be particularly noted is that X-ray fluoroscopy of the object W that is long in the transport direction is obtained by obtaining the scan interval t of the X-ray line sensor 3 by the above-described calculation. The point is that the entire still image is displayed without the image missing on the screen of the display 9.

  That is, when performing fluoroscopy of the inspection object W as shown in FIG. 4, the X-ray line sensor 3 obtained by calculation using the conveyance speed V and the conveyance direction length L of the inspection object W as described above. As shown in FIG. 5A, the X-ray fluoroscopic image captured and displayed with the X-ray transmission data under the scan interval becomes a whole image compressed in the same direction by reducing only the magnification in the conveyance direction. . On the other hand, if the overall magnification is reduced in order to display the whole image while maintaining the same vertical and horizontal magnifications, the presence or absence of foreign matter is determined when visual inspection is performed as shown in FIG. Further, in the display with the normal magnification, the entire image is not displayed and visual inspection cannot be performed as shown in FIG.

  In a conventional moving image display apparatus, in order to find small foreign matters such as nails and needles in a product having a length of 350 mm in the conveyance direction, it is necessary to inspect it at a conveyance speed of 2 m / min and a product interval of 350 mm. On the other hand, in the embodiment of the present invention, it was found that, in performing the equivalent inspection, it is possible to inspect at a product speed of 1150 mm at a conveyance speed of 12 m / min. Compared with the processing amount, it was 2.6 / min in the past, but in the embodiment of the present invention, it could be 8 / min, and the efficiency could be improved about 3 times. In addition, since the product interval can be increased, there is an advantage that errors in selecting a product determined to be NG are reduced.

In the configuration diagram of the embodiment of the present invention, a schematic diagram showing a mechanical configuration and a block diagram showing a system configuration are shown together. It is the figure which looked at the mechanical structure of embodiment of FIG. 1 from the conveyance direction. It is a time chart showing operation | movement of embodiment of this invention. It is explanatory drawing of the example of the product with which it uses for visual inspection using embodiment of this invention. 3A and 3B are explanatory diagrams of an example of an X-ray fluoroscopic image of the product of FIG. 3, wherein FIG. 3A is an example of an X-ray fluoroscopic image according to an embodiment of the present invention, and FIG. (C) is a figure which shows the example which respectively displayed the example of the fluoroscopic image, without reducing the image.

DESCRIPTION OF SYMBOLS 1 Conveyor 2 X-ray source 3 X-ray line sensor 4 Photoelectric switch 5 Control part 6 Image data taking circuit 7a, 7b Frame memory 8 Display changeover switch 9 Display 10 Operation part 11 Buzzer W Inspected object

Claims (1)

An X-ray source and an X-ray line sensor that are arranged opposite to each other, a conveyor that conveys the inspection object between these X-ray source and X-ray line sensor, and the inspection object that is to be inspected by the conveyor. In an X-ray fluoroscopic apparatus comprising display means for constructing an X-ray fluoroscopic image of an inspection object and displaying it on a display using X-ray transmission data captured when passing between line line sensors,
Input means for inputting the length along the conveyance direction of the inspection object, setting means for setting the conveyance speed of the conveyor, the length of the inspection object input by the input means, and the setting means And calculating means for calculating the scan interval of the line sensor so that the object to be inspected fits on the screen of the display device, and the X-ray line sensor is scanned at the calculated scan interval. Control means and detection means for detecting that the object to be inspected has reached between the X-ray source and the X-ray line sensor. The display means starts from the detection signal and the object to be inspected is the X-ray. While passing over the line sensor, X-ray fluoroscopic data from the X-ray line sensor is stored, and an X-ray fluoroscopic image of the inspection object is displayed after the inspection object has passed. Both, each time switching the X-ray fluoroscopic image displayed on the display device is in-line X-ray fluoroscopic apparatus characterized by comprising informing means for informing to that effect.

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