X-ray inspection equipment

Abstract

To provide an X-ray inspection device with which it is possible to obtain transmission images which are free of noise and clear, without decelerating the conveyance speed of the object to be inspected.SOLUTION: Provided is an X-ray inspection device comprising an X-ray generator 10 that irradiates the successively conveyed object W being inspected with an X-ray and an X-ray detector 11 that detects the X-ray having passed through the object W being inspected, with the X-ray generator 10 and the X-ray detector 11 being arranged so as to face each other across a conveyance path which the object W being inspected passes through. The X-ray generator 10 is constituted to be capable of rotating in the range of a prescribed angle θ when capturing an image of the object W being inspected, and the X-ray detector 11 is constituted to be capable of reciprocating, in conjunction with the rotation of the X-ray generator 10, in a direction parallel to a conveyance direction B of the object W being inspected. The X-ray generator 10 and the X-ray detector 11 perform imaging of the object W being inspected, for a duration while the object W being inspected moves from an imaging start position Pw1 to an imaging end position Pw2, with the X-ray generator 10 rotating so as to track the object W being inspected and the X-ray detector 11 moving in a conveyance direction B.SELECTED DRAWING: Figure 5

Description

Technical Field

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

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 having 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, for the increased exposure time, it is necessary to slow down the conveyance speed of the object to be inspected or, in some cases, temporarily stop it, and 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 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 includes an X-ray generator that irradiates objects to be inspected with X-rays as they are sequentially transported, and a detector that detects the X-rays that have passed through the objects to be inspected. And, capture the transmission image. The system comprises an X-ray detector and an X-ray generator, 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 presence or absence of foreign matter is determined by image processing of the aforementioned transparent image. An X-ray inspection apparatus, wherein the X-ray generator is configured to be rotatable within a predetermined angular range when imaging the object to be inspected, and the X-ray detector 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 move in the transport direction while the object to be inspected moves from the imaging start position to the imaging end position, the X-ray generator rotates to follow the object to be inspected and the X-ray detector moves in the transport direction, The aforementioned X-ray detector is The aforementioned object to be inspected From the time (t0) when the imaging start position is reached to the time (t1) when the imaging end position is reached It is configured to perform imaging.

[0008] With this configuration, the X-ray inspection apparatus according to the present invention performs imaging of the object to be inspected while the X-ray generator rotates to follow the object to be inspected and the X-ray detector moves in the transport direction as the object moves from the imaging start position to the imaging end position. 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. Therefore, the X-ray inspection apparatus according to the present invention can obtain a clear transmission image with less noise without reducing the transport speed of the object to be inspected. Therefore, there is no need to increase the current or voltage of the X-ray source in the X-ray generator to irradiate with high-power X-rays, and the output of the X-ray source can be reduced. It is possible. Furthermore, by reducing the power output of the X-ray source, it is possible to miniaturize the X-ray generator.

[0009] In the X-ray inspection apparatus according to the present invention, It is incorporated into the conveyor (2) that transports the object to be inspected,Preferably, the X-ray generator and the X-ray detector are configured such that, after the previous object to be inspected has moved to the imaging end position, they return to a position where the object to be inspected located at the imaging start position can be imaged before the next object to be transported reaches the imaging start position.

[0010] With this configuration, the X-ray inspection apparatus according to the present invention allows the X-ray generator and the X-ray detector to return the object currently at the imaging start position to an imageable position after the previous object has moved to the imaging end position and before the next object to be transported reaches the imaging start position. This allows the X-ray generator and the X-ray detector to use the time between sequentially transported objects to return the object currently at the imaging start position to an imageable position in preparation for imaging the next object.

[0011] In the X-ray inspection apparatus according to the present invention, it is preferable that the X-ray detector is configured as an area sensor.

[0012] With this configuration, the X-ray inspection apparatus according to the present invention has an X-ray detector composed of an area sensor, so a still image can be obtained without stopping the transport of the object to be inspected.

[0013] In the X-ray inspection apparatus according to the present invention, the X-ray generator and the X-ray detector are connected via a connecting bracket to form a unit, and it is preferable that the X-ray detector reciprocates in a direction parallel to the transport direction in conjunction with the rotation of the X-ray generator.

[0014] With this configuration, the X-ray inspection apparatus according to the present invention is a unit in which the X-ray generator and the X-ray detector are connected via a connecting bracket, and the X-ray detector moves back and forth in a direction parallel to the transport direction in conjunction with the rotation of the X-ray generator, so that the rotation of the X-ray generator and the movement of the X-ray detector can be synchronized without any discrepancy. [Effects of the Invention]

[0015] According to the present invention, it is possible to provide an X-ray inspection apparatus that can obtain a clear transmission image with less noise without reducing the conveyance speed of the inspected object.

Brief Description of the Drawings

[0016] [Figure 1] FIG. 1 is a schematic configuration diagram of an X-ray inspection apparatus according to an embodiment of the present invention. [Figure 2] FIG. 2 is a schematic perspective view of an X-ray inspection apparatus according to an embodiment of the present invention. [[ID=第十二]] [Figure 3] FIG. 3 is a graph showing the transition of the movement of an X-ray detector of an X-ray inspection apparatus according to an embodiment of the present invention. [Figure 4] FIG. 4 is a graph showing the transition of the rotation of an X-ray generator of an X-ray inspection apparatus according to an embodiment of the present invention. [Figure 5] FIGS. 5(a) to (e) are diagrams showing the positional relationship between an imaging unit and an inspected object of an X-ray inspection apparatus according to an embodiment of the present invention in time series. [Figure 6] FIG. 6 is a diagram showing a modified example of an X-ray inspection apparatus according to an embodiment of the present invention.

Mode for Carrying Out the Invention

[0017] Hereinafter, an X-ray inspection apparatus according to an embodiment of the present invention will be described with reference to the drawings.

[0018] (Configuration of X-ray Inspection Apparatus) As shown in FIG. 1, the X-ray inspection apparatus 1 of the present embodiment irradiates an inspected object W to be conveyed with X-rays, and inspects for foreign matter contamination, shape, etc. in the inspected object W using a transmission image obtained by detecting the transmitted X-rays. It is an X-ray inspection apparatus.

[0019] In the present embodiment, as the inspected object W, for example, a cylindrical article such as a bottle product will be described as an example, but the inspected object W is not limited to this.

[0020] The X-ray inspection apparatus 1 of this embodiment comprises 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 object W to be inspected, 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).

[0021] The enclosure is incorporated into a conveyor 2 that transports the object to be inspected W. The conveyor 2 is part of the production equipment for the object to be inspected 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 the object to be inspected W horizontally, such as top chain conveyors or belt conveyors.

[0022] 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 transport path 3 through which the object to be inspected W passes on the conveyor 2 in between.

[0023] 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 objects to be inspected W on the conveyor belt 2 as they are sequentially transported with X-rays.

[0024] 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.

[0025] The X-ray detector 11 captures a transmission image of the X-rays that have passed through the object W being irradiated with X-rays from the X-ray generator 10 onto the object W on the transport path 3. 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 applied to generate a transmission image of the density distribution based on the amount of X-ray transmission.

[0026] The control circuit 20 is connected to the display unit 12, the setting operation unit 13, and the drive unit 14.

[0027] 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 from the control circuit 20.

[0028] Furthermore, the display unit 12 displays the pass / fail judgment result of the inspected object W using characters or symbols such as "OK" or "NG". The display unit 12 also displays statistical values ​​such as the total number of inspected items, the number of good items, and the total number of NG items.

[0029] 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.

[0030] 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.

[0031] 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).

[0032] The drive unit 14 is configured as a drive source for rotating the imaging unit 30 (described later) within a predetermined angular range, and consists of an actuator such as a motor.

[0033] The control circuit 20 includes an X-ray image storage unit 21, an image processing unit 22, a determination unit 23, and a control unit 25.

[0034] The X-ray image storage unit 21 is configured to store the X-ray images received from the X-ray detector 11.

[0035] 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.

[0036] The determination unit 23 performs image processing on the X-ray image processed by the image processing unit 22 to distinguish between the object to be inspected W and foreign matter, determine whether or not foreign matter is present, and also determines whether the shape of the object to be inspected W is good or bad.

[0037] 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.

[0038] 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 rotational movement of the imaging unit 30.

[0039] (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 via a connecting bracket 31 and are unitized. As a result, the X-ray detector 11 can 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.

[0040] In this embodiment, the imaging unit 30 is composed of an X-ray generator 10, an X-ray detector 11, and a connecting bracket 31.

[0041] The lower part of the connecting bracket 31, on the X-ray generator 10 side, is connected to the rotary table 33. The rotary table 33 is rotatably supported by a rotary support unit 32, which houses a drive unit 14, and is rotated by the drive unit 14. Therefore, the connecting bracket 31 is configured to rotate with the X-ray generator 10 side as the pivot point.

[0042] A support base 34 is connected to the upper end of the connecting bracket 31 on the side facing the X-ray detector 11. The X-ray detector 11 is supported by the support base 34.

[0043] An arc-shaped elongated hole (not shown) is formed at the end of the connecting bracket 31 on the X-ray detector 11 side, penetrating the connecting bracket 31 in the vertical direction. This elongated hole is elongated in the short direction of the connecting bracket 31, 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.

[0044] A guide pin (not shown) is formed at the lower part of the support base 34 so as to protrude downward. This guide pin passes through the elongated hole of the connecting bracket 31 described above and is configured to reciprocate on a linear slider 35 that extends in a direction parallel to the transport direction B of the object to be inspected W.

[0045] As a result, the support base 34 can move back and forth linearly along the linear slider 35 even if the positional relationship between the end of the connecting bracket 31 on the X-ray detector 11 side and the linear slider 35 changes due to the rotation of the connecting bracket 31. Therefore, even if the connecting bracket 31 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.

[0046] The X-ray generator 10 is configured to rotate within a predetermined angle θ (see Figure 5(e)) when imaging the object W under inspection. Here, the angle of the X-ray generator 10 when the central axis A of the X-ray is perpendicular to the transport path 3 (the angle shown in Figure 5(d)) is defined as 0°, and rotation toward the transport direction B (downstream side of the transport direction) is called "advancing the angle," and rotation toward the opposite side of the transport direction B (upstream side of the transport direction) is called "retarding the angle."

[0047] In this embodiment, the angle at which the X-ray generator 10 is most retarded within a predetermined angle θ range is called the retarded angle DM1 (the angle shown in Figure 5(e)), and the angle at which it is most advanced is called the advanced angle DM2 (the angle shown in Figure 5(c)). The predetermined angle θ is the angle between the central axis A of the X-ray at the retarded angle DM1 and the central axis A of the X-ray at the advanced angle DM2.

[0048] The X-ray generator 10 is configured to rotate in both forward and reverse directions within a predetermined angle θ range. In other words, the X-ray generator 10 rotates in both the advance and retard directions between the slowest angle DM1 and the fastest angle DM2. The forward direction is the direction in which it follows the object being inspected W (clockwise direction in Figure 5), and the reverse direction is the direction opposite to the forward direction (counterclockwise direction in Figure 5).

[0049] Furthermore, in this embodiment, within the range of the predetermined angle θ described above, an imaging start angle D1 (the angle shown in Figure 5(a)) for starting imaging of the object under inspection W, and an imaging end angle D2 (the angle shown in Figure 5(b)) for ending imaging of the object under inspection W are set. The imaging start angle D1 is an angle that is slightly advanced from the slowest angle DM1, and is the angle of the X-ray generator 10 when imaging of the transported object under inspection W begins. The imaging end angle D2 is an angle that is slightly retarded from the fastest angle DM2, and is the angle of the X-ray generator 10 when imaging of the object under inspection W ends.

[0050] Here, the position of the object W under inspection when imaging begins is defined as the imaging start position Pw1 (see Figure 5), and the position of the object W under inspection when imaging ends is defined as the imaging end position Pw2 (see Figure 5). When the object W under inspection is located at the imaging start position Pw1, it is preferable that the central axis A of the X-ray beam passes through the center of the transport direction of the object W under inspection.

[0051] Furthermore, the position of the X-ray detector 11 when imaging begins is defined as the imaging start position Ps1 (see Figure 5), and the position of the X-ray detector 11 when imaging ends is defined as the imaging end position Ps2 (see Figure 5). In this embodiment, the position of the imaging axis perpendicular to the imaging plane of the X-ray detector 11 is treated as the position of the X-ray detector 11.

[0052] In this embodiment, the travel distance of the X-ray detector 11 from the imaging start position Ps1 to the imaging end position Ps2 is longer than the travel distance of the object under inspection W from the imaging start position Pw1 to the imaging end position Pw2. This is because there is a distance between the object under inspection W and the X-ray detector 11, and the irradiation range of the X-ray generator 10 rotates. The travel distance of the X-ray detector 11 depends on the magnification of the imaging system, and becomes longer as the magnification increases.

[0053] The X-ray generator 10 and the X-ray detector 11 are configured to follow the object W under inspection as it moves from the imaging start position Pw1 to the imaging end position Pw2. The X-ray generator 10 rotates from the imaging start angle D1 to the imaging end angle D2, while the X-ray detector 11 moves in the transport direction B, and imaging of the object W under inspection is performed.

[0054] The X-ray generator 10 and X-ray detector 11 are configured to return to a position where the object W currently at the imaging start position Pw1 can be imaged (hereinafter referred to as the "unit home position") after the previous object W has moved to the imaging end position Pw2, and before the next object W to be transported reaches the imaging start position Pw1.

[0055] The unit home position refers to the positions of the X-ray generator 10 and X-ray detector 11 shown in Figure 5(a). Specifically, for the X-ray generator 10, it is the imaging start angle D1, and for the X-ray detector 11, it is the imaging start position Ps1.

[0056] At this time, by increasing the speed at which the X-ray generator 10 and the X-ray detector 11 return to their unit home positions, that is, by increasing the angular velocity of the imaging unit 30, the interval between the sequentially transported objects W can be reduced, and the number of objects W inspected per unit time can be increased.

[0057] (Transition of the imaging unit's movement) Next, the transition of movement of the imaging unit 30 will be explained with reference to Figures 3 to 5.

[0058] In Figure 3, the dashed line shows the transition of movement of the object under inspection W, and the solid line shows the transition of movement of the X-ray detector 11. In Figure 3, the transition of movement of the X-ray detector 11 is explained using the example of the object under inspection W1, which is transported first, and the object under inspection W2, which is transported next, among the objects under inspection W that are transported sequentially. Note that in the dashed line showing the transition of movement of the object under inspection W, there are some thick solid lines, which indicate that the object under inspection W is being imaged.

[0059] Figures 5(a) to 5(e) show the positional relationship between the imaging unit 30 and the object under inspection W at each time from time t0 to time t4 shown in Figures 3 and 4, with Figure 5(a) corresponding to time t0, Figure 5(b) to time t1, Figure 5(c) to time t2, Figure 5(d) to time t3, and Figure 5(e) to time t4.

[0060] As shown in Figure 3, when the object under inspection W1 reaches the imaging start position Pw1 at time t0, the X-ray generator 10 advances from the imaging start angle D1 to follow the object under inspection W1 (see Figure 4), and in conjunction with this, the X-ray detector 11 starts imaging the object under inspection W1 while moving toward the imaging end position Ps2 at a speed faster than the transport speed of the object under inspection W1.

[0061] In other words, as shown in Figure 5(a), when the center of the transport direction of the object to be inspected W1 coincides with the central axis A of the X-ray generator 10, the X-ray generator 10 and the X-ray detector 11 begin imaging the object to be inspected W1 and begin tracking the object to be inspected W1.

[0062] Subsequently, until imaging of the object under inspection W1 is completed, that is, until the object under inspection W1 reaches the imaging completion position Pw2, imaging of the object under inspection W1 is performed while maintaining the positional relationship between the center of the transport direction of the object under inspection W1 and the central axis A of the X-ray beam. During imaging of the object under inspection W1, the angular velocity of the X-ray generator 10 and the moving speed of the X-ray detector 11 remain constant. In other words, during imaging of the object under inspection W1, the X-ray generator 10 moves in a uniform circular motion, and the X-ray detector 11 moves in a uniform linear motion.

[0063] Next, when the object under inspection W1 reaches the imaging completion position Pw2 (the position shown in Figure 5(b)) at time t1, imaging of the object under inspection W1 is completed, and the operation to return the X-ray generator 10 and X-ray detector 11 to their unit home positions begins. Specifically, the control unit 25 starts the reverse drive of the drive unit 14.

[0064] At this time, the X-ray generator 10 and the X-ray detector 11 reverse their rotation and movement directions at the position shown in Figure 5(c) after the X-ray generator 10 has advanced beyond the imaging completion angle D2 to the maximum advance angle DM2 and the X-ray detector 11 has slightly passed the imaging completion position Ps2 in the transport direction B.

[0065] At time t2, as the X-ray generator 10 and X-ray detector 11 begin to return to their unit home positions, a positive angular acceleration is applied to the rotation of the X-ray generator 10, and consequently, a positive acceleration is applied to the X-ray detector 11. In other words, the X-ray generator 10 and X-ray detector 11 accelerate and rotate and move toward the unit home position from the position shown in Figure 5(c).

[0066] Next, at time t3, the angular acceleration applied to the rotation of the X-ray generator 10 is switched from positive to negative (see Figure 4). That is, the drive unit 14 is controlled by the control unit 25 so that the X-ray generator 10, which was rotating with positive angular acceleration, is given negative angular acceleration at time t3, and it begins to decelerate. The X-ray detector 11 also begins to decelerate accordingly.

[0067] Time t3 is, for example, the timing when the central axis A of the X-ray generator 10 reaches half the distance traveled by the object W under inspection, i.e., an intermediate position between the imaging start position Pw1 and the imaging end position Pw2 (the position shown in Figure 5(d)), and can also be defined as t3 = (t2 + t4) / 2. Note that the timing of switching between positive and negative angular acceleration applied to the rotation of the X-ray generator 10 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, as the X-ray generator 10 and X-ray detector 11 are decelerating, the X-ray generator 10 is delayed beyond the imaging start angle D1 to the slowest angle DM1, and the X-ray detector 11 has slightly passed the imaging start position Ps1 in the opposite direction to the transport direction B (upstream of the transport direction). At time t4, the deceleration ends, and at this timing, the rotation direction and the movement direction are reversed. At this time, as shown in Figure 5(e), the object to be inspected W2 has not yet reached the imaging start position Pw1.

[0069] Subsequently, when the object under inspection W2 reaches the imaging start position Pw1 at time t5, the X-ray generator 10 advances its angle to follow the object under inspection W2, and in conjunction with this, the X-ray detector 11 moves toward the imaging end position Ps2 at a speed faster than the transport speed of the object under inspection W2, and begins imaging the object under inspection W2. From this point onward, the process is the same as for the object under inspection 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 rotational motion and reciprocating motion.

[0071] (Effects and Benefits) As described above, in the X-ray inspection apparatus according to this embodiment, the X-ray generator 10 and the X-ray detector 11 rotate to follow the object under inspection W as it moves from the imaging start position Pw1 to the imaging end position Pw2, and the X-ray detector 11 moves in the transport direction B while imaging the object under inspection W. Therefore, compared to a configuration in which the X-ray generator 10 and the X-ray detector 11 are fixed, the exposure time can be extended without reducing the transport speed of the object under inspection W. For this reason, the X-ray inspection apparatus according to this embodiment can obtain a clear transmission image with less noise without reducing the transport speed of the object under inspection W.

[0072] In this case, if the transport of the object to be inspected W is stopped each time it is exposed in order to extend the exposure time, for example, if the object to be inspected W is a container filled with liquid, the liquid surface will shake each time it is stopped, and transport cannot be started again until the shaking of the liquid surface subsides. For this reason, it is not possible to increase the number of objects to be inspected W per unit time.

[0073] Since the X-ray inspection apparatus according to this embodiment does not require stopping the transport of the object to be inspected W, the liquid level fluctuations described above do not occur, and the number of objects to be inspected W per unit time can be increased.

[0074] Furthermore, as described above, the X-ray inspection apparatus according to this embodiment obtains a clear transmission image with less noise by ensuring a long exposure time by moving the X-ray generator 10 and the X-ray detector 11 back and forth. Therefore, it is not necessary to increase the current or voltage of the X-ray source of the X-ray generator 10 to irradiate with high-power X-rays, and the output of the X-ray source can be reduced. Moreover, by reducing the output of the X-ray source, the X-ray generator 10 can be made smaller.

[0075] Furthermore, in the X-ray inspection apparatus according to this embodiment, the X-ray generator 10 and the X-ray detector 11 return to their unit home positions after the previous object to be inspected W has moved to the imaging completion position Pw2, but before the next object to be inspected W reaches the imaging start position Pw1. Therefore, the gap time between sequentially transported objects to be inspected W can be used to return the X-ray generator 10 and the X-ray detector 11 to their unit home positions in preparation for imaging the next object to be inspected W.

[0076] Furthermore, since the X-ray inspection apparatus according to this embodiment is configured with an area sensor as the X-ray detector 11, a still image can be obtained without stopping the transport of the object to be inspected W.

[0077] Furthermore, in this embodiment, the X-ray inspection apparatus is a unit in which the X-ray generator 10 and the X-ray detector 11 are connected via a connecting bracket 31. Since the X-ray detector 11 reciprocates in a direction parallel to the transport direction B in conjunction with the rotation of the X-ray generator 10, the rotation of the X-ray generator 10 and the movement of the X-ray detector 11 can be synchronized without any discrepancy.

[0078] (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 object to be inspected 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.

[0079] 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 rotate and move as a single unit.

[0080] Furthermore, in the X-ray inspection apparatus according to this embodiment, the X-ray generator 10 and the X-ray detector 11 are configured as a single unit that can rotate and reciprocate together. 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 rotate and reciprocate independently. In this case, the control unit 25 synchronizes the rotation of the X-ray generator 10 with the movement of the X-ray detector 11.

[0081] Furthermore, in this embodiment, an example has been described in which the X-ray inspection apparatus according to the present invention is applied to an X-ray inspection apparatus incorporated into a conveyor 2 having a straight transport path 3. However, the invention is not limited to this, and may also be applied to an X-ray inspection apparatus incorporated into a conveyor 2 having a curved transport path 3, as shown in Figure 6.

[0082] In this case, the X-ray detector 11 is positioned relative to the X-ray generator 10 so that it can reciprocate while the central axis A of the X-rays from the X-ray generator 10 and the imaging axis of the X-ray detector 11 remain aligned. In the example shown in Figure 6, the X-ray generator 10 and the X-ray detector 11 may be unitized so that they rotate and move together, or they may be configured to rotate and move independently.

[0083] 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]

[0084] 1. X-ray inspection device 2 Conveyor 3. Conveyor path 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 30 imaging units 31 Connecting Bracket 32 Rotating support section 33 Rotating Table 34 Support stand 35 Linear Slider W, W1, W2 Test object θ Predetermined angle D1: Imaging start angle D2 imaging end angle DM1 Most retarded angle DM2 Maximum advance angle Pw1, Ps1 imaging start position Pw2, Ps2 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 and captures a transmitted image, An X-ray inspection apparatus is provided 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, and the transmitted image is processed to determine whether or not foreign matter is present, 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 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 an X-ray inspection apparatus in which, while the object to be inspected moves from an imaging start position (Pw1) to an imaging end position (Pw2), the X-ray generator rotates to follow the object to be inspected and the X-ray detector moves in the transport direction, and the X-ray detector performs imaging from the time (t0) when the object to be inspected reaches the imaging start position to the time (t1) when it reaches the imaging end position.

2. Incorporated into a conveyor (2) that transports the object to be inspected, The X-ray inspection apparatus according to claim 1, characterized in that the X-ray generator and the X-ray detector are configured to return to a position where the object to be inspected located at the imaging start position can be imaged 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.

3. The X-ray inspection apparatus according to claim 1 or 2, characterized in that the X-ray detector is configured by an area sensor.

4. The X-ray inspection apparatus according to claim 1 or 2, characterized in that the X-ray generator and the X-ray detector are connected and unitized via a connecting bracket (31), and the X-ray detector reciprocates in a direction parallel to the transport direction in conjunction with the rotation of the X-ray generator.

5. The X-ray inspection apparatus according to claim 3, wherein the X-ray generator and the X-ray detector are connected via a connecting bracket (31) to form a unit, and the X-ray detector reciprocates in a direction parallel to the transport direction in conjunction with the rotation of the X-ray generator.

Images