X-ray inspection equipment and X-ray inspection system

Abstract

To provide an X-ray inspection device and an X-ray inspection system that can obtain a clear transmission image with less noise without reducing a conveyance speed of an object to be inspected.SOLUTION: An X-ray inspection device has an X-ray generator and an X-ray detector that can reciprocate in a direction parallel to a conveyance direction of a workpiece W, picks up an image of the workpiece W while moving in the conveyance direction from an imaging start position P1 to an imaging end position P2 at a speed equal to a conveyance speed of the workpiece W, and after the completion of imaging, returns to the imaging start position P1 before a next workpiece W reaches the imaging start position P1. The X-ray inspection device comprises: a reference image information storage section in which reference image information which is image information of a reference image obtained by picking up an image of the workpiece W in advance is stored; a determination section that determines whether or not image information of an X-ray image obtained through imaging matches the reference image information; and a control section that, when the determination section determines that the image information of the X-ray image obtained through imaging does not match the reference image information, adjusts a moving speed of an imaging unit.SELECTED DRAWING: Figure 9

Description

Technical Field

[0001] The present invention relates to an X-ray inspection apparatus and an X-ray inspection system.

Background Art

[0002] Patent Document 1 discloses an X-ray foreign object inspection apparatus including an X-ray generator that is disposed at a predetermined height above an inspection space in the middle of a conveyance path and irradiates an object to be inspected that is sequentially conveyed with X-rays in the inspection space, and an X-ray line sensor that is disposed opposite to the X-ray generator in a conveyance unit and detects X-rays transmitted through the object to be inspected.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, in the X-ray foreign object inspection apparatus described in Patent Document 1, if the exposure time for the object to be inspected is short, the obtained transmission image becomes a noisy image. Also, for example, when inspecting an object to be inspected with a relatively large thickness, if the exposure time is short, the obtained transmission image becomes an unclear image. Therefore, if the exposure time for the object to be inspected is short, the inspection accuracy cannot be improved.

[0005] On the other hand, if the exposure time is increased, a transmission image with less noise and clear can be obtained. However, as the exposure time is increased, it is necessary to slow down the conveyance speed of the object to be inspected or, in some cases, temporarily stop it, and an efficient inspection cannot be performed.

[0006] The present invention has been made in view of the circumstances described above, and aims to provide an X-ray inspection apparatus and an X-ray inspection system that can obtain clear transmission images with low noise without reducing the transport speed of the object to be inspected. [Means for solving the problem]

[0007] The X-ray inspection apparatus according to the present invention comprises an X-ray generator that irradiates objects to be inspected with X-rays as they are sequentially transported, and an X-ray detector that detects the X-rays that have passed through the objects to be inspected, wherein the X-ray generator and the X-ray detector are arranged opposite each other across a transport path through which the objects to be inspected pass, and the X-ray generator, when imaging the objects to be inspected, The object under inspection reciprocates in a direction parallel to the transport direction. It is configured to be movable, and the X-ray detector is Connected to the aforementioned X-ray generator, and the X-ray generator The X-ray generator and X-ray detector are configured to move back and forth in a direction parallel to the transport direction of the object to be inspected, in conjunction with the movement of the object to be inspected. The X-ray generator and X-ray detector are configured to perform tracking movement that follows the object to be inspected as the object moves from the imaging start position to the imaging end position. and The X-ray detector and The X-ray inspection device is configured to move in the transport direction while imaging the object to be inspected, and after the previous object to be inspected has moved to the imaging end position, before the next object to be transported reaches the imaging start position, it returns to a position where the object to be inspected located at the imaging start position can be imaged. The X-ray inspection device includes a reference image information storage unit which stores reference image information, which is image information of a reference image of the object to be inspected taken in advance, a determination unit which determines whether the image information of the X-ray image obtained by imaging matches the reference image information, and if the determination unit determines that the image information of the X-ray image obtained by imaging does not match the reference image information, The aforementioned X-ray generator and the X-ray detector The aforementioned tracking movement It includes a control unit that adjusts the speed of movement.

[0008] With this configuration, the X-ray inspection apparatus according to the present invention has an X-ray generator that moves in a tracking manner to follow the object being inspected from the imaging start position to the imaging end position. and X-ray detector andSince the X-ray generator and X-ray detector move in the transport direction while imaging the object under inspection, the exposure time can be extended without reducing the transport speed of the object under inspection, compared to a configuration where the X-ray generator and X-ray detector are fixed for imaging.

[0009] Furthermore, if the judgment unit determines that the image information of the X-ray image obtained through imaging does not match the reference image information, X-ray generator and X-ray detector Follow movement Since it is equipped with a control unit that adjusts the movement speed, the movement of the object being inspected and X-ray generator Furthermore, even if a discrepancy occurs between the tracking movement of the X-ray detector and the X-ray image, resulting in, for example, the object being inspected in the X-ray image becoming unclear, or the position of the object being inspected in the X-ray image shifting from the position of the workpiece image in the reference image, and thus degrading the quality of the X-ray image, X-ray generator and X-ray detector Follow movement The quality of X-ray images can be improved by adjusting the movement speed. Therefore, the X-ray inspection apparatus according to the present invention can obtain a clear transmission image with low noise without reducing the transport speed of the object to be inspected.

[0010] The X-ray inspection apparatus according to the present invention comprises an X-ray generator that irradiates an object to be inspected with X-rays as it is sequentially transported, and an X-ray detector that detects the X-rays that have passed through the object to be inspected, wherein the X-ray generator and the X-ray detector are arranged opposite each other across a transport path through which the object to be inspected passes, the X-ray generator is configured to be rotatable within a predetermined angular range when imaging the object to be inspected, the X-ray detector is connected to the X-ray generator and is configured to reciprocate in a direction parallel to the transport direction of the object to be inspected in conjunction with the rotation of the X-ray generator, and the X-ray generator and the X-ray detector are configured to rotate and move in a manner that follows the object to be inspected as the object moves from the imaging start position to the imaging end position, the X-ray generator rotates and the X-ray detector moves in a manner that follows the object to be inspected. The X-ray inspection apparatus is configured to move in the transport direction while imaging the object to be inspected, and after the previous object to be inspected has moved to the imaging end position, before the next object to be transported reaches the imaging start position, it is configured to return the object to be inspected at the imaging start position to a position where it can be imaged. The X-ray inspection apparatus includes a reference image information storage unit which stores reference image information, which is image information of a reference image of the object to be inspected taken in advance; a determination unit which determines whether the image information of the X-ray image obtained by imaging matches the reference image information; and a control unit which adjusts the movement speed of the tracking movement caused by the rotation of the X-ray generator and the movement of the X-ray detector when the determination unit determines that the image information of the X-ray image obtained by imaging does not match the reference image information. With this configuration, the X-ray inspection apparatus according to the present invention rotates to follow the object to be inspected from the imaging start position to the imaging end position, and the X-ray detector moves in the transport direction while imaging the object to be inspected. Therefore, compared to a configuration in which the X-ray generator and X-ray detector are fixed for imaging, the exposure time can be extended without reducing the transport speed of the object to be inspected. Furthermore, if the judgment unit determines that the image information of the X-ray image obtained by imaging does not match the reference image information, the system is equipped with a control unit that adjusts the speed of the tracking movement caused by the rotation of the X-ray generator and the movement of the X-ray detector. Therefore, even if a discrepancy occurs between the movement of the object under inspection and the tracking movement caused by the rotation of the X-ray generator and the movement of the X-ray detector, resulting in, for example, the object under inspection becoming unclear in the X-ray image or the position of the object under inspection in the X-ray image shifting from the position of the workpiece image in the reference image, thus degrading the quality of the X-ray image, the quality of the X-ray image can be improved by adjusting the speed of the tracking movement caused by the rotation of the X-ray generator and the movement of the X-ray detector. Therefore, the X-ray inspection apparatus according to the present invention can obtain a clear transmission image with low noise without reducing the transport speed of the object to be inspected.

[0011] In the X-ray inspection apparatus according to the present invention, the determination unit determines that the image information of the X-ray image obtained by imaging does not match the reference image information when the contrast of the object to be inspected in the X-ray image obtained by imaging is different from the contrast of the object to be inspected in the reference image, and the control unit preferably adjusts the movement speed of the tracking movement in the case of the first pattern.

[0012] With this configuration, the X-ray inspection apparatus according to the present invention determines that the image information of the X-ray image obtained by imaging does not match the reference image information when the contrast of the object to be inspected in the X-ray image obtained by imaging differs from the contrast of the object to be inspected in the reference image, and in this case adjusts the tracking movement speed. X-ray generator Furthermore, the tracking speed of the X-ray detector can be matched to the transport speed of the object being inspected. This allows the contrast of the object being inspected in the X-ray image obtained through imaging to be matched with the contrast of the object being inspected in the reference image, thereby improving the quality of the X-ray image.

[0013] In the X-ray inspection apparatus according to the present invention, the determination unit determines that the position of the object to be inspected in the X-ray image obtained by imaging is different from the position of the object to be inspected in the reference image, and that this is a second pattern in which the image information of the X-ray image obtained by imaging does not match the reference image information. The control unit preferably adjusts the movement speed of the return movement in the case of the second pattern.

[0014] With this configuration, the X-ray inspection apparatus according to the present invention determines that if the position of the object to be inspected in the X-ray image obtained by imaging differs from the position of the object to be inspected in the reference image, it is a second pattern in which the image information of the X-ray image obtained by imaging does not match the reference image information, and in this case, it adjusts the movement speed of the return movement. X-ray generator Furthermore, the timing at which the X-ray detector returns the object under inspection, which is located at the imaging start position, to a position where it can be imaged can be adjusted. This makes it possible to synchronize the timing at which the object under inspection reaches the imaging start position with the timing at which the X-ray generator and X-ray detector start imaging. As a result, the position of the object under inspection in the X-ray image obtained by imaging can be matched with the position of the object under inspection in the reference image, thereby improving the quality of the X-ray image.

[0015] In the X-ray inspection apparatus according to the present invention, when the position of the object to be inspected in the X-ray image obtained by the imaging is different from the position of the object to be inspected in the reference image, the determination unit determines that it is a second pattern in which the image information of the X-ray image obtained by the imaging does not match the reference image information. In the case of the second pattern, it is preferable that the control unit notifies the outside that the image information of the X-ray image obtained by the imaging does not match the reference image information.

[0016] With this configuration, when the position of the object to be inspected in the X-ray image obtained by imaging is different from the position of the object to be inspected in the reference image, the X-ray inspection apparatus according to the present invention determines that it is a second pattern in which the image information of the X-ray image obtained by imaging does not match the reference image information. In this case, since it notifies the outside that the image information of the X-ray image obtained by imaging does not match the reference image information, it is possible to inform the user that it is necessary to improve the quality of the X-ray image. The user can change the settings of, for example, a transport device that transports the object to be inspected to the X-ray inspection apparatus or a loading device that loads the object to be inspected into the transport device in response to the above notification.

[0017] In the X-ray inspection apparatus according to the present invention, the X-ray generator and the X-ray detector are configured to perform imaging even during the return movement. The determination unit determines whether or not there is an object to be inspected in the X-ray image captured during the return movement. When it is determined by the determination unit that there is an object to be inspected in the X-ray image captured during the return movement, it is preferable that the control unit notify the outside that there is an abnormality in the conveyance of the object to be inspected.

[0018] With this configuration, when it is determined that there is an object to be inspected in the X-ray image captured during the return movement, the X-ray inspection apparatus according to the present invention notifies the outside that there is an abnormality in the conveyance of the object to be inspected. X-ray generatorDepending on the adjustment of the moving speed of the X-ray detector, it may not be possible to correspond to the conveyance interval or conveyance speed of the object to be inspected, and it may be possible to inform the user that the conveyance interval of the object to be inspected may become smaller or the conveyance speed may become faster. Upon receiving the aforementioned notification, the user can change the settings of, for example, the conveyance device that conveys the object to be inspected to the X-ray inspection apparatus or the input device that inputs the object to be inspected to the conveyance device.

[0021] The X-ray inspection system according to the present invention is as set forth in claim 1 or claim 2 An X-ray inspection system including the X-ray inspection apparatus described in the above, a conveyance device that conveys an object to be inspected to the X-ray inspection apparatus, and an input device that inputs the object to be inspected to the conveyance device, wherein the determination unit determines that when the position of the object to be inspected in the X-ray image obtained by the imaging is different from the position of the object to be inspected in the reference image, the image information of the X-ray image obtained by the imaging does not match the reference image information, and is a second pattern, and the control unit has a configuration that outputs a signal to the input device to adjust the timing of inputting the object to be inspected to the conveyance device in the case of the second pattern.

[0022] With this configuration, when the position of the object to be inspected in the X-ray image obtained by imaging is different from the position of the object to be inspected in the reference image, the X-ray inspection system according to the present invention determines that the image information of the X-ray image obtained by imaging does not match the reference image information, and is a second pattern. In this case, a signal is output to the input device to adjust the timing of inputting the object to be inspected to the conveyance device, so that the timing of inputting the object to be inspected in the input device can be adjusted. As a result, the timing at which the object to be inspected reaches the imaging start position and the timing at which the X-ray generator and the X-ray detector start imaging can be made to coincide. As a result, the position of the object to be inspected in the X-ray image obtained by imaging and the position of the object to be inspected in the reference image can be made to coincide, and the quality of the X-ray image can be improved.

Advantages of the Invention

[0023] According to the present invention, it is possible to provide an X-ray inspection apparatus and an X-ray inspection system that can obtain clear transmission images with low noise without reducing the transport speed of the object to be inspected. [Brief explanation of the drawing]

[0024] [Figure 1] Figure 1 is a schematic diagram of an X-ray inspection apparatus according to one embodiment of the present invention. [Figure 2] Figure 2 is a schematic perspective view of an X-ray inspection apparatus according to one embodiment of the present invention. [Figure 3] Figure 3 is a graph showing the movement transition of the imaging unit of an X-ray inspection apparatus according to one embodiment of the present invention. [Figure 4] Figures 4(a) to 4(e) show the positional relationship between the imaging unit and the workpiece of an X-ray inspection apparatus according to one embodiment of the present invention, in chronological order. [Figure 5] Figure 5 shows a workpiece image in an X-ray image captured by an imaging unit of an X-ray inspection apparatus according to one embodiment of the present invention, where (a) shows a case where the workpiece image is blurred, and (b) shows a case where the position of the workpiece image in the X-ray image is shifted from the position of the workpiece image in the reference image. [Figure 6] Figure 6 is a time chart for the case where the tracking speed of the imaging unit of the X-ray inspection apparatus according to one embodiment of the present invention does not match the transport speed of the workpiece (first pattern). [Figure 7] Figure 7 is a time chart for the case where the timing at which the imaging unit of the X-ray inspection apparatus according to one embodiment of the present invention starts imaging does not coincide with the timing at which the workpiece reaches the imaging start position (second pattern). [Figure 8] Figure 8 is a time chart showing the case where the first pattern in Figure 6 and the second pattern in Figure 7 occur simultaneously. [Figure 9] Figure 9 is a flowchart showing the flow of the tracking misalignment determination process performed in an X-ray inspection apparatus according to one embodiment of the present invention. [Figure 10]Figure 10 is a schematic block diagram showing an X-ray inspection system including an X-ray inspection apparatus according to one embodiment of the present invention. [Figure 11] Figure 11 is a perspective view showing a modified example of an X-ray inspection apparatus according to one embodiment of the present invention. [Modes for carrying out the invention]

[0025] The following describes an X-ray inspection apparatus according to one embodiment of the present invention, with reference to the drawings.

[0026] (Configuration of X-ray inspection equipment) As shown in Figure 1, the X-ray inspection apparatus 1 of this embodiment is an X-ray inspection apparatus that irradiates a workpiece W, which is an object to be inspected, with X-rays, detects the transmitted X-rays, and uses the transmitted image obtained to inspect the workpiece W for foreign matter contamination, shape, etc.

[0027] In this embodiment, the workpiece W is described using, for example, a cylindrical article such as a bottle product, but the workpiece W is not limited to this.

[0028] The X-ray inspection apparatus 1 of this embodiment includes a housing (not shown), an X-ray generator 10 that generates X-rays, an X-ray detector 11 that detects X-rays that have passed through the workpiece W, and a control circuit 20. The X-ray generator 10, the X-ray detector 11, and the control circuit 20 are housed in the housing (not shown).

[0029] The enclosure is incorporated into a conveyor 2 that transports the workpiece W. The conveyor 2 is part of the production equipment for the workpiece W and is configured separately from the X-ray inspection device 1. Thus, the X-ray inspection device 1 is an integrated type X-ray inspection device that is incorporated into a separate conveyor 2, and is incorporated into existing conveyors that transport workpiece W horizontally, such as top chain conveyors or belt conveyors.

[0030] The X-ray generator 10 and the X-ray detector 11 are positioned opposite each other in the width direction of the conveyor 2, with the conveyor path 3 through which the workpiece W on the conveyor 2 passes.

[0031] The X-ray generator 10 generates X-rays by irradiating an electron beam from the cathode of an X-ray tube (not shown) located inside it onto a target at the anode, and irradiates the generated X-rays radially so that the area indicated by the dashed line in Figure 1 is imaged. In this way, the X-ray generator 10 irradiates the workpieces W on the conveyor belt 2 as they are sequentially transported with X-rays.

[0032] The X-ray detector 11 comprises a photodiode (not shown) and a plurality of X-ray detection elements (not shown) consisting of scintillators provided on the photodiode. The X-ray detector 11 is composed of an area sensor in which the X-ray detection elements are arranged in a planar manner in the transport direction and in a direction perpendicular to this transport direction.

[0033] The X-ray detector 11 captures a transmission image (hereinafter referred to as "X-ray image") of the X-rays that have passed through the workpiece W on the transport path 3 after being irradiated with X-rays from the X-ray generator 10. Specifically, the X-rays are converted into an optical signal by the scintillator of the X-ray detection element, and this optical signal is converted into an electrical signal by a photodiode. Further processing such as noise reduction is then performed to generate an X-ray image of the density distribution based on the amount of X-ray transmission.

[0034] The control circuit 20 is connected to the display unit 12, the setting operation unit 13, and the drive unit 14.

[0035] The display unit 12 consists of a flat-panel display or the like, and is configured to output information to the user. The display unit 12 displays images such as inspection results and judgment results from the control circuit 20.

[0036] Furthermore, the display unit 12 displays the pass / fail judgment result of the workpiece W using characters or symbols such as "OK" or "NG". The display unit 12 also displays statistical values ​​such as the total number of inspections, the number of good items, and the total number of NG items. In addition, the display unit 12 displays, in addition to the judgment result from the judgment unit 27 described later, whether there is an abnormality in the transport of the workpiece W based on that judgment result, using characters or symbols.

[0037] The display content and display mode of the display unit 12 are determined based on default settings or requests made by predetermined key operations from the setting operation unit 13.

[0038] The setting operation unit 13 is used to input various parameters and other settings to the control circuit 20. The setting operation unit 13 consists of multiple keys and switches operated by the user, and is used to input various parameters and other settings to the control circuit 20 and to select the operating mode.

[0039] In this embodiment, the display unit 12 and the setting operation unit 13 are integrated as a touch panel display and are located on the upper front of a housing (not shown).

[0040] The drive unit 14 is configured as a drive source that moves the imaging unit 30 (described later) back and forth in a direction parallel to the transport direction of the workpiece W, and consists of an actuator such as a motor.

[0041] The control circuit 20 includes an X-ray image storage unit 21, an image processing unit 22, a determination unit 23, a control unit 25, a reference image information storage unit 26, and a decision unit 27.

[0042] The X-ray image storage unit 21 is configured to store the X-ray images received from the X-ray detector 11.

[0043] The image processing unit 22 applies various image processing algorithms to the X-ray image read from the X-ray image storage unit 21 to perform image processing. Here, the image processing algorithm consists of a combination of multiple image processing filters.

[0044] The determination unit 23 distinguishes between the workpiece W and foreign matter in the X-ray image processed by the image processing unit 22 to determine whether or not foreign matter is present, and also determines whether or not the shape of the workpiece W is good.

[0045] The control unit 25 has a CPU and memory that serves as a storage area or work area for the control program, and controls the entire X-ray inspection apparatus 1. The control contents of the control unit 25 include control of the display content and display format of the display unit 12.

[0046] Furthermore, the control unit 25 controls the drive of the drive unit 14. By controlling the drive of the drive unit 14, the control unit 25 controls the reciprocating movement of the imaging unit 30 and adjusts the movement speed of the imaging unit 30.

[0047] The reference image information storage unit 26 stores image information (hereinafter referred to as "reference image information") of an X-ray image (hereinafter referred to as "reference image") of a sample of the workpiece W that has been captured in advance. As the reference image, for example, a still image of the sample of the workpiece W may be used, or an X-ray image may be used that is captured while tracking the sample of the workpiece W after the movement speed of the imaging unit 30, the transport speed of the workpiece W, and the transport interval of the workpiece W have been adjusted.

[0048] Reference image information includes various types of information that can identify the reference image, such as contrast information of workpiece W in the reference image and the central coordinates of workpiece W in the reference image.

[0049] The determination unit 27 determines whether the image information of the X-ray image acquired while tracking the workpiece W matches the reference image information. Here, "matching the reference image information" includes not only cases where the image information is a perfect match with the reference image information, but also cases where, for example, the difference between the various numerical values ​​indicating the image information of the acquired X-ray image and the various numerical values ​​indicating the reference image information falls within an acceptable range.

[0050] (Imaging unit) As shown in Figure 2, in the X-ray inspection apparatus 1 of this embodiment, the X-ray generator 10 and the X-ray detector 11 are connected to each other by a movable bracket 31, and are unitized so that they can move back and forth in a direction parallel to the transport direction B of the workpiece W.

[0051] In this embodiment, the imaging unit 30 is composed of an X-ray generator 10, an X-ray detector 11, and a movable bracket 31.

[0052] The movable bracket 31 is configured to reciprocate on a linear slider 32 that extends in a direction parallel to the transport direction B of the workpiece W. The reciprocating movement of the movable bracket 31 is achieved by the drive unit 14.

[0053] A pair of guide rails 33 and 34 are provided at the bottom of the movable bracket 31, positioned opposite each other in a direction perpendicular to the transport direction B, with the linear slider 32 in between. The movable bracket 31 moves back and forth while being guided by the pair of guide rails 33 and 34.

[0054] As a result, the X-ray generator 10 and the X-ray detector 11 move back and forth between the imaging start position (the position shown in Figure 4(a)) and the imaging end position (the position shown in Figure 4(b)).

[0055] Specifically, the X-ray generator 10 and the X-ray detector 11 are configured to move in the transport direction B from the transport speed of the workpiece W to the end of the imaging position, at a speed equal to the transport speed of the workpiece W, while imaging the workpiece W. In other words, the X-ray irradiation range from the X-ray generator 10 moves in the transport direction B, following the workpiece W during imaging. The X-ray detector 11 also moves in a direction parallel to the transport direction B in conjunction with the movement of the X-ray irradiation range.

[0056] The X-ray generator 10 and X-ray detector 11 are configured to return to the imaging start position after the previous workpiece W has moved to the imaging end position, but before the next workpiece W to be transported reaches the imaging start position. In this embodiment, it is desirable that the next workpiece W is located at the imaging start position when the X-ray generator 10 and X-ray detector 11 return to the imaging start position. In other words, it is desirable that the timing of the X-ray generator 10 and X-ray detector 11 returning to the imaging start position coincides with the timing of the next workpiece W reaching the imaging start position.

[0057] It is desirable that the movement speed of the X-ray generator 10 and X-ray detector 11 back to the imaging start position is faster than the transport speed of the workpiece W. In other words, it is desirable that the movement speed of the X-ray generator 10 and X-ray detector 11 in the direction opposite to the transport direction B is faster than the movement speed in the transport direction B. This makes it possible to reduce the interval between sequentially transported workpieces W, and to increase the number of workpieces W inspected per unit time.

[0058] (Transition of the imaging unit's movement) Next, the transition of movement of the imaging unit 30 will be described with reference to Figures 3 and 4.

[0059] In Figure 3, the dashed line shows the transition of movement of the workpiece W, and the solid line shows the transition of movement of the imaging unit 30. In Figure 3, the transition of movement of the imaging unit 30 is explained using the workpiece W1, which is transported first, and the workpiece W2, which is transported next, as an example. In Figure 3, P1 indicates the imaging start position, and P2 indicates the imaging end position.

[0060] Figures 4(a) to 4(e) show the positional relationship between the imaging unit 30 and the workpiece W at each time from time t0 to time t4 shown in Figure 3, with Figure 4(a) corresponding to time t0, Figure 4(b) to time t1, Figure 4(c) to time t2, Figure 4(d) to time t3, and Figure 4(e) to time t4, respectively.

[0061] As shown in Figure 3, when the workpiece W1 reaches the imaging start position P1 at time t0, the imaging unit 30 starts imaging the workpiece W1 while moving toward the imaging end position P2 at a speed equal to the transport speed of the workpiece W1, following the workpiece W1. In other words, as shown in Figure 4(a), when the center of the transport direction of the workpiece W1 coincides with the imaging axis A perpendicular to the imaging plane of the X-ray detector 11, the X-ray generator 10 and the X-ray detector 11 start imaging the workpiece W1 and begin following the workpiece W1.

[0062] Subsequently, the imaging of the workpiece W1 is performed while the workpiece W1 and the imaging unit 30 move at a constant speed until the imaging of the workpiece W1 is completed, that is, until the workpiece W1 reaches the imaging completion position P2.

[0063] Next, when the workpiece W1 and the imaging unit 30 reach the imaging completion position P2 (the position shown in Figure 4(b)) at time t1, imaging of the workpiece W1 is completed, and the imaging unit 30 begins to return to the imaging start position P1. Specifically, the control unit 25 starts the reverse drive of the drive unit 14.

[0064] At this point, the imaging unit 30 slightly overshoots the imaging end position P2 in the transport direction B, then reverses its direction of movement at that position (the position shown in Figure 4(c)) and begins to return to the imaging start position P1.

[0065] At time t2, as the imaging unit 30 begins to return to the imaging start position P1, a positive acceleration is applied to the imaging unit 30. In other words, the imaging unit 30 accelerates and moves from the position shown in Figure 4(c) towards the imaging start position P1.

[0066] Next, at time t3, the acceleration applied to the imaging unit 30 is switched from positive to negative. That is, the drive unit 14 is controlled by the control unit 25 so that the imaging unit 30, which was moving with positive acceleration, is given negative acceleration at time t3, and it begins to decelerate.

[0067] Time t3 is, for example, the timing when the imaging unit 30 reaches half the distance it has traveled, i.e., the midpoint between the imaging start position P1 and the imaging end position P2 (the position shown in Figure 4(d)), and can also be defined as t3 = (t2 + t4) / 2. Note that the timing for switching between positive and negative acceleration applied to the imaging unit 30 is not limited to the timing described above, but may be changed as appropriate according to the specifications of the imaging unit 30 and the drive unit 14.

[0068] Next, the decelerating imaging unit 30 slightly overshoots the imaging start position P1 in the opposite direction to the transport direction B, and then decelerates at time t4. At this point, the direction of movement reverses, and it begins moving towards the imaging end position P2. At this time, as shown in Figure 4(e), the workpiece W2 has not yet reached the imaging start position P1.

[0069] Subsequently, when the workpiece W2 reaches the imaging start position P1 at time t5, the imaging unit 30 moves toward the imaging end position P2 at a speed equal to the transport speed of the workpiece W2, following the workpiece W2, and begins imaging the workpiece W2. From this point onward, the process is the same as for workpiece W1.

[0070] In this manner, the drive unit 14 is controlled by the control unit 25 so that the X-ray generator 10 and the X-ray detector 11 periodically repeat reciprocating movements.

[0071] (Adjusting the movement speed of the imaging unit) Next, we will explain how to adjust the movement speed of the imaging unit, referring to Figures 5 to 8.

[0072] When imaging the workpiece W, if the movement of the workpiece W and the movement of the imaging unit 30 are not synchronized, for example, the workpiece image Ir in the acquired X-ray image may be blurred relative to the workpiece image Is in the reference image (as shown in Figure 5(a)), or the position of the workpiece image Ir in the acquired X-ray image may be shifted relative to the workpiece image Is in the reference image (as shown in Figure 5(b)), resulting in a decrease in the quality of the acquired X-ray image.

[0073] Here, examples of patterns in which the movement of the workpiece W and the movement of the imaging unit 30 are not synchronized include the following first and second patterns.

[0074] The first pattern, as shown in Figure 6, is one in which the transport speed of workpiece W1 is different from that of workpiece WH and workpiece WL, while the transport speed of workpiece W1 is the same as the transport speed of the imaging unit 30 during tracking movement (hereinafter referred to as "tracking speed"). Workpiece WH is transported at a faster transport speed than workpiece W1. Workpiece WL is transported at a slower transport speed than workpiece W1.

[0075] In the first pattern, the workpiece image in the acquired X-ray image is blurred. For example, Figure 5(a) shows a comparison of the workpiece image Ir, obtained when the workpiece WH was imaged, with the workpiece image Is in the reference image.

[0076] When imaging workpiece W, imaging is performed at a frame rate such as 20 frames / second. Therefore, if workpiece WH moves at a speed faster than the imaging unit 30, as shown in Figure 5(a), the workpiece image of workpiece WH will be stretched in the transport direction (right in Figure 5), as shown in workpiece image Ir, and the contrast will gradually decrease towards both ends in the direction parallel to the transport direction of the workpiece image, resulting in a blurred image. Note that when imaging workpiece WL, the direction of stretching will be opposite to the transport direction (left in Figure 5).

[0077] Therefore, the determination unit 27 of this embodiment determines that the image information of the X-ray image obtained by imaging does not match the reference image information when the contrast of the work image in the X-ray image obtained by imaging during tracking movement is different from the contrast of the work image in the reference image.

[0078] In this embodiment, in order to eliminate the first pattern, the control unit 25 adjusts the tracking speed of the imaging unit 30 during tracking movement.

[0079] Specifically, the control unit 25 controls the drive unit 14 to increase the tracking speed of the imaging unit 30 if the tracking speed of the imaging unit 30 is slower than the transport speed of the workpiece W. Conversely, the control unit 25 controls the drive unit 14 to decrease the tracking speed of the imaging unit 30 if the tracking speed of the imaging unit 30 is faster than the transport speed of the workpiece W.

[0080] If the control unit 25 needs to adjust the movement speed of the imaging unit 30 during the return movement by adjusting the tracking speed of the imaging unit 30 as described above, it is preferable to also adjust the movement speed of the imaging unit 30 during the return movement.

[0081] The second pattern, as shown in Figure 7, is one in which the timing at which the imaging unit 30 is positioned at the imaging start position P1 is different from the timing at which the workpiece W reaches the imaging start position P1.

[0082] Workpiece W(-) represents the transition of a workpiece when it reaches the imaging start position P1 at a faster time than the imaging unit 30 is positioned at the imaging start position P1. For example, if the interval between sequentially transported workpieces becomes narrow, the workpiece may reach the imaging start position P1 before the imaging unit 30 is positioned at the imaging start position P1, as shown in workpiece W(-).

[0083] Workpiece W(+) represents a transition of the workpiece when it reaches the imaging start position P1 at a later time than when the imaging unit 30 is positioned at the imaging start position P1. For example, if the interval between sequentially transported workpieces widens, the workpiece will reach the imaging start position P1 at a later time than when the imaging unit 30 is positioned at the imaging start position P1, as shown by workpiece W(+).

[0084] In the second pattern, the position of the workpiece image Ir in the acquired X-ray image is shifted from the position of the workpiece image Is in the reference image. For example, Figure 5(b) compares the workpiece image Ir when workpiece W(+) is acquired with the workpiece image Is in the reference image.

[0085] When workpiece W(+) is imaged, as shown in Figure 5(b), the workpiece image Ir of workpiece W(+) is shifted in the opposite direction to the transport direction (to the left in Figure 5) relative to the workpiece image Is in the reference image. Similarly, when workpiece W(-) is imaged, the workpiece image Ir of workpiece W(-) is shifted in the transport direction (to the right in Figure 5) relative to the workpiece image Is in the reference image.

[0086] Therefore, the determination unit 27 of this embodiment determines that if the position of the workpiece image in the X-ray image obtained by imaging during tracking movement is different from the position of the workpiece image in the reference image, it is a second pattern in which the image information of the X-ray image obtained by imaging does not match the reference image information.

[0087] In this embodiment, in order to eliminate the second pattern, the control unit 25 adjusts the movement speed of the imaging unit 30 during the return movement, i.e., the acceleration and deceleration (hereinafter collectively referred to as "acceleration and deceleration").

[0088] Specifically, if the workpiece W reaches the imaging start position P1 at a timing earlier than the timing when the imaging unit 30 is positioned at the imaging start position P1 (in the case of workpiece W(-) in Figure 7), the control unit 25 controls the drive unit 14 to increase the acceleration / deceleration of the imaging unit 30 during the return movement. Conversely, if the imaging unit 30 reaches the imaging start position P1 at a timing later than the timing when the imaging unit 30 is positioned at the imaging start position P1, the control unit 25 controls the drive unit 14 to decrease the acceleration / deceleration of the imaging unit 30 during the return movement.

[0089] Furthermore, if the second pattern occurs, the control unit 25 may adjust the timing of acceleration and deceleration instead of, or in addition to, adjusting the acceleration and deceleration of the imaging unit 30 during the return movement.

[0090] Here, the first and second patterns described above can occur simultaneously. In this case, the transition of workpiece W will be, for example, a transition such as workpiece WH(-) or workpiece WL(+) as shown in Figure 8.

[0091] This represents the transition of the workpiece WH(-) when it moves at a speed faster than the imaging unit 30 and reaches the imaging start position P1 at a time earlier than when the imaging unit 30 is positioned at the imaging start position P1.

[0092] Workpiece WL(+) is the transition of a workpiece that moves at a slower speed than the imaging unit 30 and reaches the imaging start position P1 at a later time than the time when the imaging unit 30 is positioned at the imaging start position P1.

[0093] Work WH(-) and Work WL(+) are just examples of combinations that occur when the first pattern and the second pattern occur simultaneously. Other combinations that result in transitions such as Work WL(-) or Work WH(+) are also possible.

[0094] When the first pattern and the second pattern occur simultaneously, the control unit 25 preferably adjusts the tracking speed of the imaging unit 30 during tracking movement and the acceleration / deceleration degree of the imaging unit 30 during return movement.

[0095] The patterns in Figures 6 to 8 described above are examples of the transition of the workpiece W when a tracking misalignment occurs, where the movement of the workpiece W and the movement of the imaging unit 30 are not synchronized, but are not limited to these examples.

[0096] (Tracking discrepancy detection process) Next, referring to the flowchart in Figure 9, the flow of the tracking deviation determination process performed by the control circuit 20 will be explained.

[0097] As shown in Figure 9, the control circuit 20 captures an image of the workpiece W as the imaging unit 30 moves in a tracking motion (step S1).

[0098] Next, the control circuit 20 compares the image information of the X-ray image acquired in step S1 with the reference image information stored in the reference image information storage unit 26 (step S2).

[0099] If the control circuit 20 determines, as a result of the comparison in step S2, that the difference between the image information of the X-ray image acquired in step S1 and the reference image information stored in the reference image information storage unit 26 falls within an acceptable range (including an agreement), it proceeds to step S9.

[0100] If the control circuit 20 determines, based on the comparison in step S2, that the tracking speed of the imaging unit 30 during tracking movement does not match the transport speed of the workpiece W (the first pattern), it proceeds to step S3.

[0101] If the control circuit 20 determines, based on the comparison in step S2, that there is a second pattern in which the timing at which the imaging unit 30 is positioned at the imaging start position P1 and the timing at which the workpiece W reaches the imaging start position P1 are different, it proceeds to step S6.

[0102] In step S3, the control circuit 20 determines whether the tracking speed of the imaging unit 30 is less than the transport speed of the workpiece W. Specifically, the control circuit 20 can determine whether the tracking speed of the imaging unit 30 is less than the transport speed of the workpiece W by determining whether the workpiece image in the X-ray image acquired in step S1 is stretched in either the transport direction or the opposite direction relative to the workpiece image in the reference image.

[0103] If the control circuit 20 determines in step S3 that the tracking speed of the imaging unit 30 is less than the transport speed of the workpiece W, it increases the tracking speed of the imaging unit 30, i.e., speeds up the tracking speed (step S4), and then proceeds to step S9.

[0104] If the control circuit 20 determines in step S3 that the tracking speed of the imaging unit 30 is not less than the transport speed of the workpiece W, that is, that the tracking speed of the imaging unit 30 is greater than the transport speed of the workpiece W, then it reduces the tracking speed of the imaging unit 30, i.e., slows down the tracking speed (step S5), and proceeds to step S9.

[0105] Here, if the tracking speed and the transport speed match, it is determined to be within the acceptable range in step S2. Therefore, if the answer is "No" in step S3, the case where the tracking speed and the transport speed match is not included.

[0106] In step S6, the control circuit 20 determines whether the position of the workpiece image in the X-ray image acquired in step S1 is ahead of the workpiece image in the reference image in the transport direction of the workpiece W.

[0107] If the control circuit 20 determines in step S6 that the position of the workpiece image in the X-ray image acquired in step S1 has advanced further in the transport direction of the workpiece W than the workpiece image in the reference image, it increases the acceleration and deceleration of the imaging unit 30 during the return movement, that is, it increases the absolute value of the acceleration and deceleration (step S7), and proceeds to step S9. As a result, both the acceleration and deceleration of the imaging unit 30 during the return movement increase.

[0108] If the control circuit 20 determines in step S6 that the position of the workpiece image in the X-ray image acquired in step S1 is not ahead of the workpiece image in the reference image in the direction of workpiece W transport, that is, it is lagging in the opposite direction to the transport direction, then it reduces the acceleration and deceleration of the imaging unit 30 during the return movement, i.e., it reduces the absolute value of the acceleration and deceleration (step S8), and proceeds to step S9. As a result, both the acceleration and deceleration of the imaging unit 30 during the return movement are reduced.

[0109] Here, if the position of the workpiece image in the X-ray image acquired in step S1 matches the position of the workpiece image in the reference image, it is judged as within the acceptable range in step S2. Therefore, if the answer in step S6 is "No", the case in which the position of the workpiece image in the X-ray image acquired in step S1 matches the position of the workpiece image in the reference image is not included.

[0110] In step S9, the control circuit 20 determines whether or not the workpiece image is present in the X-ray image captured within a predetermined period during the return movement. In other words, the control circuit 20 is configured to perform imaging during a predetermined period during the return movement, separate from the imaging in step S1, and determines whether or not the workpiece image is present in the X-ray image captured within that predetermined period.

[0111] The predetermined period is the period during which the workpiece W will not appear in the X-ray image if no tracking misalignment occurs. For example, in this embodiment, this corresponds to the period from time t2 to time t4 in Figure 3.

[0112] If the control circuit 20 determines in step S9 that there is no workpiece image in the X-ray image captured within a predetermined period during the return movement, it terminates the tracking misalignment determination process.

[0113] If the control circuit 20 determines in step S9 that a workpiece image is present in the X-ray image captured within a predetermined period during the return movement, it determines that the workpiece transport interval has become so narrow that the tracking misalignment cannot be resolved by increasing or decreasing the tracking speed or acceleration / deceleration rate as described above. In this case, it notifies an external party, for example via the display unit 12 (step S10), of a workpiece transport abnormality indicating that there is an abnormality in the transport of the workpiece, and terminates the tracking misalignment determination process.

[0114] (Effects and Benefits) As described above, in this embodiment, the X-ray inspection apparatus performs imaging of the workpiece W while the X-ray generator 10 moves to follow the workpiece W from the imaging start position P1 to the imaging end position P2, and the X-ray detector 11 moves in the transport direction. Therefore, compared to a configuration in which the X-ray generator 10 and X-ray detector 11 are fixed for imaging, the exposure time can be extended without reducing the transport speed of the workpiece W.

[0115] Furthermore, the system includes a control unit 25 that adjusts the movement speed of the imaging unit 30 if the determination unit 27 determines that the image information of the X-ray image obtained by imaging during tracking movement does not match the reference image information. Therefore, even if a discrepancy occurs between the movement of the workpiece W and the tracking movement of the imaging unit 30, causing, for example, the workpiece image in the X-ray image to become unclear or the position of the workpiece image in the X-ray image to shift from the position of the workpiece image in the reference image, thus degrading the quality of the X-ray image, the quality of the X-ray image can be improved by adjusting the movement speed of the imaging unit 30.

[0116] Therefore, the X-ray inspection apparatus according to this embodiment can obtain a clear transmission image with low noise without reducing the transport speed of the object to be inspected.

[0117] Furthermore, in this embodiment, if the contrast of the workpiece image in the X-ray image obtained by imaging during tracking movement differs from the contrast of the workpiece image in the reference image, it is determined that this is a first pattern in which the image information of the X-ray image obtained by imaging during tracking movement does not match the reference image information. In this case, the tracking movement speed of the imaging unit 30 is adjusted, so that the tracking movement speed of the imaging unit 30 can be matched to the transport speed of the workpiece W. As a result, the contrast of the workpiece image in the X-ray image obtained by imaging during tracking movement can be matched with the contrast of the workpiece image in the reference image, thereby improving the quality of the X-ray image.

[0118] Furthermore, in this embodiment, if the position of the workpiece image in the X-ray image obtained by imaging during tracking movement differs from the position of the workpiece image in the reference image, the X-ray inspection apparatus determines that this is a second pattern in which the image information of the X-ray image obtained by imaging during tracking movement does not match the reference image information. In this case, the movement speed of the return movement of the imaging unit 30 is adjusted, thereby adjusting the timing at which the imaging unit 30 returns to the imaging start position P1. This makes it possible to match the timing at which the workpiece W reaches the imaging start position P1 with the timing at which the X-ray generator 10 and the X-ray detector 11 start imaging. As a result, the position of the workpiece image in the X-ray image obtained by imaging during tracking movement can be matched with the position of the workpiece image in the reference image, thereby improving the quality of the X-ray image.

[0119] Furthermore, the X-ray inspection apparatus according to this embodiment notifies the outside of a workpiece transport abnormality if it is determined that a workpiece W is present in the X-ray image captured within a predetermined period during the return movement of the imaging unit 30. This allows the user to be informed that the workpiece transport interval may have become too small or the transport speed too fast, to the point where adjusting the movement speed of the imaging unit 30 may not be sufficient to accommodate the transport interval and transport speed of the workpiece W. Upon receiving the notification, the user can, for example, change the settings of the transport device that transports the workpiece W to the X-ray inspection apparatus 1 or the input device that loads the workpiece W into the transport device.

[0120] Furthermore, in this embodiment, the X-ray inspection apparatus is unitized so that the X-ray generator 10 and the X-ray detector 11 can move together in a direction parallel to the transport direction B, allowing the X-ray generator 10 and the X-ray detector 11 to move at the same speed without any misalignment.

[0121] (modified version) In this embodiment, an example has been described in which the X-ray inspection apparatus according to the present invention is applied to a horizontal irradiation type X-ray inspection apparatus in which the X-ray generator 10 and the X-ray detector 11 are arranged facing each other in a horizontal direction perpendicular to the transport direction of the workpiece W, with the transport path 3 in between. However, it may also be applied to an X-ray inspection apparatus of the type in which the X-ray generator 10 and the X-ray detector 11 are arranged facing each other in a vertical direction with the transport path 3 in between.

[0122] Furthermore, although the X-ray inspection apparatus according to this embodiment is configured to have one set of X-ray generator 10 and X-ray detector 11, it may also be configured to have two or more sets of X-ray generator 10 and X-ray detector 11. In this case, it is preferable to unitize these two or more sets of X-ray generator 10 and X-ray detector 11 so that they can be moved as a single unit.

[0123] Furthermore, in the X-ray inspection apparatus according to this embodiment, the X-ray generator 10 and the X-ray detector 11 are configured to be unitized and reciprocate as a single unit. However, the apparatus is not limited to this configuration, and the X-ray generator 10 and the X-ray detector 11 may be configured to be reciprocate independently. In this case, the control unit 25 synchronizes the movement of the X-ray generator 10 and the movement of the X-ray detector 11.

[0124] Furthermore, in the X-ray inspection apparatus according to this embodiment, if the second pattern occurs, the control unit 25 may, in addition to or instead of adjusting the acceleration / deceleration degree of the imaging unit 30 during the return movement, notify the outside, for example via the display unit 12, that the image information of the X-ray image obtained by imaging during the tracking movement does not match the reference image information.

[0125] In this case, the system notifies the external system that the image information of the X-ray image obtained during tracking movement does not match the reference image information, thereby informing the user that the quality of the X-ray image needs to be improved. Upon receiving the notification, the user can, for example, change the settings of the transport device that transports the workpiece W to the X-ray inspection device 1 or the loading device that loads the workpiece W into the transport device.

[0126] Furthermore, in the X-ray inspection apparatus according to this embodiment, if the first pattern or the second pattern occurs, or if the first pattern and the second pattern occur simultaneously, the position of the workpiece image in each X-ray image may be corrected by image processing so that it matches the position of the workpiece image in the reference image, and the corrected X-ray images may be superimposed to generate a single X-ray image. Moreover, when generating a single X-ray image as described above, X-ray images that are heavily degraded due to disturbances, for example, may not be superimposed.

[0127] Furthermore, in the X-ray inspection apparatus according to this embodiment, an emitter and receiver may be provided in front of the imaging start position P1, with the transport path 3 in between. The emitter and receiver detect the workpiece W being transported along the transport path 3 toward the imaging start position P1.

[0128] In this case, the presence or absence of the workpiece W can be monitored by the light emitter and receiver. For example, if the transport interval of the workpiece W becomes so large that it is difficult to synchronize the movement of the workpiece W with the movement of the imaging unit 30 by adjusting the movement speed of the imaging unit 30, the operation of the imaging unit 30 can be stopped.

[0129] If the workpiece W is detected by the light transmitter / receiver after the imaging unit 30 has stopped, the imaging unit 30 can be restarted upon detection of the workpiece W by the light transmitter / receiver. In this case, the start timing of the tracking movement of the imaging unit 30 should be set based on the timing of detection of the workpiece W by the light transmitter / receiver.

[0130] (X-ray inspection system) As shown in Figure 10, the X-ray inspection apparatus 1 of this embodiment may be used in an X-ray inspection system 100 which is interconnected with an input device 4 and a transport device 5 via a network 6.

[0131] The input device 4 is a device that loads the workpieces W into the conveying device 5. As the input device 4, for example, a timing screw type input device can be used, which uses a timing screw to align multiple workpieces W that are transported from the conveyor of the previous process in an irregular or close-contact state to a predetermined interval and then feed them out at a predetermined speed.

[0132] The transport device 5 has the conveyor 2 described above and transports the workpiece W fed in from the input device 4 to the X-ray inspection device 1.

[0133] In the X-ray inspection system 100 of this embodiment, when the determination unit 27 of the X-ray inspection device 1 determines that a second pattern has occurred, the control unit 25 of the X-ray inspection device 1 outputs a signal to the input device 4 to adjust the timing of inputting the workpiece W into the transport device 5.

[0134] In this case, the control unit 25 of the X-ray inspection apparatus 1 outputs the above-mentioned signal to the input device 4 for adjusting the timing of inputting the workpiece W, in addition to or instead of adjusting the acceleration / deceleration rate of the imaging unit 30 during the return movement.

[0135] Thus, in this embodiment, the X-ray inspection system 100 determines that the position of the workpiece image in the X-ray image obtained by imaging during tracking movement differs from the position of the workpiece image in the reference image, and in this case outputs a signal to the input device 4 to adjust the timing of inputting the workpiece W into the transport device 5, so that the input device 4 can adjust the timing of inputting the workpiece W.

[0136] This allows the timing at which the workpiece W reaches the imaging start position P1 to coincide with the timing at which the X-ray generator 10 and X-ray detector 11 begin imaging. As a result, the position of the workpiece image in the X-ray image obtained by imaging during tracking movement can be matched with the position of the workpiece image in the reference image, thereby improving the quality of the X-ray image.

[0137] (X-ray inspection devices with different tracking methods) The X-ray inspection apparatus to which the present invention is applied may also be an X-ray inspection apparatus 101, as shown in Figure 11, which has a different tracking method than the X-ray inspection apparatus 1 of this embodiment.

[0138] As shown in Figure 11, the X-ray inspection apparatus 101 is a unit in which the X-ray generator 10 and the X-ray detector 11 are connected to each other via a connecting bracket 51. This allows the X-ray detector 11 to reciprocate in a direction parallel to the transport direction B of the object to be inspected, in conjunction with the rotation of the X-ray generator 10.

[0139] In the X-ray inspection device 101, the imaging unit 50 is composed of an X-ray generator 10, an X-ray detector 11, and a connecting bracket 51.

[0140] The lower part of the connecting bracket 51, on the X-ray generator 10 side, is connected to the rotary table 53. The rotary table 53 is rotatably supported by a rotary support unit 52, which houses a drive unit 14, and is rotated by the drive unit 14. Therefore, the connecting bracket 51 is configured to rotate with the X-ray generator 10 side as the pivot point.

[0141] A support base 54 is connected to the upper end of the connecting bracket 51 on the side facing the X-ray detector 11. The X-ray detector 11 is supported by the support base 54.

[0142] An arc-shaped elongated hole (not shown) is formed at the end of the connecting bracket 51 on the X-ray detector 11 side, penetrating the connecting bracket 51 in the vertical direction. This elongated hole is elongated in the short direction of the connecting bracket 51, that is, in the horizontal direction perpendicular to the central axis A of the X-ray, and is formed to bulge in an arc toward the X-ray generator 10 side.

[0143] A guide pin (not shown) is formed at the lower part of the support base 54 so as to protrude downward. This guide pin passes through the elongated hole of the connecting bracket 51 described above and is configured to reciprocate on a linear slider 55 that extends in a direction parallel to the conveying direction B of the workpiece W.

[0144] As a result, the support base 54 can move linearly back and forth along the linear slider 55 even if the positional relationship between the end of the connecting bracket 51 on the X-ray detector 11 side and the linear slider 55 changes due to the rotation of the connecting bracket 51. Therefore, even if the connecting bracket 51 rotates, the X-ray detector 11 can move back and forth in a direction parallel to the transport direction while maintaining the distance between it and the transport path 3.

[0145] In the X-ray inspection apparatus 101, the X-ray generator 10 is configured to be rotatable within a predetermined angle range so that the X-ray irradiation range can reciprocate in a direction parallel to the transport direction B when imaging the workpiece W.

[0146] While embodiments of the present invention have been disclosed, it will be apparent to those skilled in the art that modifications can be made without departing from the scope of the invention. All such modifications and equivalents are intended to be included in the following claims. [Explanation of Symbols]

[0147] 1.101 X-ray inspection equipment 2 Conveyor 3. Conveyor path 4 Feeding device 5. Conveying device 6 Network 10 X-ray generator 11 X-ray detectors 12 Display section 13. Setting Operation Unit 14 Drive Unit 20 Control circuits 21 X-ray image storage unit 22 Image Processing Unit 23 Judgment section 25 Control Unit 26 Reference Image Information Storage Unit 27 Judgment Department 30, 50 imaging units 31 Moving bracket 32, 55 Linear Slider 33, 34 Guide rails 51 Connecting Bracket 52 Rotating support part 53 Rotating Table 54 Support stand 100 X-ray inspection systems W, W1, W2 Workpiece (object to be inspected) P1 Imaging start position P2 imaging end position

Claims

1. An X-ray generator (10) that irradiates the objects to be inspected (W) as they are transported sequentially, The system includes an X-ray detector (11) that detects the X-rays that have passed through the object to be inspected, An X-ray inspection apparatus in which the X-ray generator and the X-ray detector are arranged opposite each other across a transport path (3) through which the object to be inspected passes, The X-ray generator is configured to reciprocate in a direction parallel to the transport direction of the object to be inspected when imaging the object to be inspected. The X-ray detector is connected to the X-ray generator and is configured to reciprocate in a direction parallel to the transport direction of the object to be inspected, in conjunction with the movement of the X-ray generator. The X-ray generator and the X-ray detector are configured to move in the transport direction while imaging the object to be inspected, following the object to be inspected as it moves from the imaging start position (P1) to the imaging end position (P2). After the previous object to be inspected has moved to the imaging end position, the X-ray generator and the X-ray detector are configured to move back to a position where the object to be inspected at the imaging start position can be imaged before the next object to be transported reaches the imaging start position. The aforementioned X-ray inspection apparatus, A reference image information storage unit (26) stores reference image information, which is image information of a reference image of the object to be inspected taken in advance, A determination unit (27) that determines whether the image information of the X-ray image obtained by the imaging matches the reference image information, An X-ray inspection apparatus comprising: a control unit (25) that adjusts the tracking speed of the X-ray generator and the X-ray detector when the determination unit determines that the image information of the X-ray image obtained by the aforementioned imaging does not match the reference image information.

2. An X-ray generator (10) that irradiates X-rays onto objects (W) to be inspected as they are transported sequentially, The system includes an X-ray detector (11) that detects the X-rays that have passed through the object to be inspected, An X-ray inspection apparatus in which the X-ray generator and the X-ray detector are arranged opposite each other across a transport path (3) through which the object to be inspected passes, The X-ray generator is configured to be rotatable within a predetermined angular range when imaging the object under inspection. The X-ray detector is connected to the X-ray generator and is configured to reciprocate in a direction parallel to the transport direction of the object to be inspected, in conjunction with the rotation of the X-ray generator. The X-ray generator and the X-ray detector are configured such that, while the object to be inspected moves from the imaging start position (P1) to the imaging end position (P2), the X-ray generator rotates to follow the object to be inspected, and the X-ray detector moves in the transport direction while imaging the object to be inspected. After the previous object to be inspected has moved to the imaging end position, and before the next object to be transported reaches the imaging start position, the X-ray generator and the X-ray detector are configured to return the object to the imaging start position to a position where it can be imaged. The aforementioned X-ray inspection apparatus, A reference image information storage unit (26) stores reference image information, which is image information of a reference image of the object to be inspected taken in advance, A determination unit (27) that determines whether the image information of the X-ray image obtained by the imaging matches the reference image information, An X-ray inspection apparatus comprising: a control unit (25) that adjusts the speed of the tracking movement caused by the rotation of the X-ray generator and the movement of the X-ray detector when the determination unit determines that the image information of the X-ray image obtained by the aforementioned imaging does not match the reference image information.

3. The determination unit determines that if the contrast of the object to be inspected in the X-ray image obtained by imaging is different from the contrast of the object to be inspected in the reference image, it is a first pattern in which the image information of the X-ray image obtained by imaging does not match the reference image information. The X-ray inspection apparatus according to claim 1 or 2, wherein the control unit adjusts the movement speed of the tracking movement in the case of the first pattern.

4. The determination unit determines that if the position of the object to be inspected in the X-ray image obtained by imaging is different from the position of the object to be inspected in the reference image, it is a second pattern in which the image information of the X-ray image obtained by imaging does not match the reference image information. The X-ray inspection apparatus according to claim 1 or 2, wherein the control unit adjusts the movement speed of the return movement in the case of the second pattern.

5. The determination unit determines that if the position of the object to be inspected in the X-ray image obtained by imaging is different from the position of the object to be inspected in the reference image, it is a second pattern in which the image information of the X-ray image obtained by imaging does not match the reference image information. The X-ray inspection apparatus according to claim 3, wherein the control unit adjusts the movement speed of the return movement in the case of the second pattern.

6. The determination unit determines that if the position of the object to be inspected in the X-ray image obtained by imaging is different from the position of the object to be inspected in the reference image, it is a second pattern in which the image information of the X-ray image obtained by imaging does not match the reference image information. The X-ray inspection apparatus according to claim 1 or 2, wherein the control unit, in the case of the second pattern, notifies the outside that the image information of the X-ray image obtained by imaging does not match the reference image information.

7. When the position of the object to be inspected in the X-ray image obtained by imaging is different from the position of the object to be inspected in the reference image, the determination unit determines that the image information of the X-ray image obtained by imaging does not match the reference image information, and The X-ray inspection apparatus according to claim 3, wherein the control unit, in the case of the second pattern, notifies the outside that the image information of the X-ray image obtained by imaging does not match the reference image information.

8. The X-ray generator and the X-ray detector are configured to perform imaging even during the return movement. The determination unit determines whether or not the object to be inspected is present in the X-ray image captured during the return movement. The X-ray inspection apparatus according to claim 1 or 2, wherein the control unit notifies the outside that there is an abnormality in the transport of the object to be inspected when the determination unit determines that the object to be inspected is present in the X-ray image captured during the return movement.

9. An X-ray inspection apparatus (1) according to claim 1 or claim 2, The X-ray inspection apparatus is equipped with a transport device (5) for transporting the object to be inspected, An X-ray inspection system comprising a loading device (4) for loading the object to be inspected into the transport device, The determination unit determines that if the position of the object to be inspected in the X-ray image obtained by imaging is different from the position of the object to be inspected in the reference image, it is a second pattern in which the image information of the X-ray image obtained by imaging does not match the reference image information. The control unit, in the case of the second pattern, is an X-ray inspection system that outputs a signal to the input device to adjust the timing of inputting the object to be inspected into the transport device.

Images