JP2009216679A - X-ray fluoroscopic inspection apparatus - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an X-ray fluoroscopic inspection apparatus capable of achieving facilitation such as validation operation after inspection by easily grasping 3-D positional information of the internal defects in an inspecting object even after the X-ray fluoroscopic inspection. <P>SOLUTION: The X-ray fluoroscopic inspection apparatus includes: an optical camera 10 for photographing a workpiece W arranged on a sample stage 7 provided between an X-ray generation unit 1 and an X-ray detector 2; a viewing position/direction display means for hourly displaying the fluoroscopic image viewing position and direction on the display 25 together with the X-ray fluoroscopic image of the workpiece W using the appearance image of the workpiece taken by the optical camera for time sequentially continuously or intermittently recording the X-ray fluoroscopic image of the workpiece W displayed on the display 25; and a recording means 29 for recording contents by the viewing position/direction display means displayed corresponding to the hourly X-ray fluoroscopic image. By reproducing the recoded contents, the display similar to the viewing X-ray fluoroscopic image can be freely reproduced and capable of three-dimensionally grasping the position or structure etc. of the defects in the workpiece W. <P>COPYRIGHT: (C)2009,JPO&INPIT

Description

  The present invention relates to an industrial X-ray fluoroscopic inspection apparatus that uses X-rays to inspect an inspection object such as various industrial products, and in particular, to inspect internal defects of a three-dimensional article such as an aluminum die casting. The present invention relates to a suitable fluoroscopic inspection apparatus.

  In an industrial X-ray fluoroscopic inspection apparatus that irradiates an inspection object with X-rays and constructs and displays an X-ray fluoroscopic image of the inspection object using the transmitted X-rays, in general, an X-ray generator and an X-ray generation apparatus A structure is adopted in which the line detectors are arranged so as to face each other and a sample stage for placing an object to be inspected therebetween is provided. In this type of X-ray fluoroscopic inspection apparatus, normally, a rotating table, an XY table, or the like is disposed in combination with a sample stage, and the rotating table or the XY table is driven by an operator's operation, whereby an object to be inspected is X-rayed. By rotating or moving between the X-ray detector and the X-ray detector, the fluoroscopic observation direction and the fluoroscopic observation position of the inspection object can be arbitrarily changed.

  This type of X-ray fluoroscopic inspection apparatus normally has a function of storing a fluoroscopic image as a still image by giving a command while the fluoroscopic image is displayed. For example, a fluoroscopy in which a defect is found By storing the image, verification is possible after inspection.

  Here, in such an X-ray fluoroscopic inspection apparatus, a usage method of inspecting an inspection object at a high magnification and inspecting for the presence or absence of an internal defect or the like is frequently used. In such a case, the fluoroscopic field is inspected. In some cases, it becomes a part of the object, and it is difficult for the operator to determine which part of the inspection object is seen through on the inspection object. Also, with regard to the fluoroscopic observation direction, it may be difficult to determine from which direction the obtained fluoroscopic image is seen through.

In order to solve such a problem, an optical camera such as a CCD camera is conventionally provided in this type of X-ray fluoroscopic inspection apparatus, and an object to be inspected placed on the sample stage is photographed with the optical camera prior to the fluoroscopic inspection. An apparatus is known in which an external appearance image is displayed together with an X-ray fluoroscopic image, and the fluoroscopic observation position and direction are displayed using the external appearance image (see, for example, Patent Document 1). Specifically, the inspection object is mounted on a rotary table and rotated, and the inspection object is photographed from a plurality of directions by an optical camera placed on the side, and an appearance image from each direction is stored. Whenever the fluoroscopic observation direction is changed by rotating the rotary table during fluoroscopic inspection, an external appearance image is displayed from the same direction as the fluoroscopic direction, and the fluoroscopic observation position (the center of the fluoroscopic visual field) is displayed on the external appearance image. By superimposing and displaying the mark representing the position, it is possible to inform the operator of the fluoroscopic observation position and direction every moment, so that the operator can intuitively grasp the fluoroscopic observation position and direction.
JP 2006-90792 A

  By the way, in the internal observation of the article by X-ray fluoroscopy, the X-ray transmitted through the article includes information on all the parts existing in the traveling direction, and therefore, for example, the inside of a three-dimensional article such as aluminum die casting is used. When inspecting for defects such as the presence or absence of voids or cracks inside the article, or the presence or absence of foreign matter, etc. by performing fluoroscopic observation, on the fluoroscopic image with the observation position and observation direction fixed during fluoroscopic observation Even if a defect such as a void is recognized, position information (depth information) in the X-ray fluoroscopic direction of the defect cannot be obtained from the stationary X-ray fluoroscopic image. In such inspection, the aforementioned fluoroscopic observation position is obtained by observing the transition of the position of the defect on the live fluoroscopic image while changing the fluoroscopic observation direction by appropriately driving a rotary table or the like by an operator's operation. In addition to the display of the direction and the direction, it is possible to grasp the three-dimensional information such as the position and shape / structure of the defect in the inspection object.

  However, even if an X-ray fluoroscopic image in which a defect such as a void is stored using an apparatus having a function of storing a fluoroscopic image at an arbitrary time point as a still image as described above, the still image is stored later. Even if the defect is to be verified, the position of the void or the like on the one two-dimensional X-ray fluoroscopic image cannot be known.

  The present invention has been made in view of such circumstances, and it is an object of the present invention to provide an X-ray fluoroscopic inspection apparatus capable of easily grasping depth information of defects such as voids even after live fluoroscopic observation. Yes.

  In order to solve the above-described problems, in the X-ray fluoroscopic inspection apparatus of the present invention, a sample stage for arranging an object to be inspected is arranged between an X-ray generator and an X-ray detector that are arranged to face each other. A fluoroscopic image based on the detection result of the X-ray transmitted through the inspection object placed on the stage is displayed on the display, and the relative position between the pair of the X-ray generator and the X-ray detector and the sample stage is displayed. In an X-ray inspection apparatus having a moving mechanism that changes the fluoroscopic observation position and direction of an inspection object by changing the optical camera for imaging the inspection object placed on the sample stage, and the inspection by the optical camera An observation position / direction display means for displaying an external appearance image of the object and displaying the fluoroscopic observation position and direction of the inspection object using the external appearance image, and the inspection object displayed on the display By means of recording means for storing continuously or intermittently over time, and for recording together with the display contents by the observation position / direction display means displayed corresponding to the respective fluoroscopic images. Characterized (Claim 1).

  Here, in the present invention, there is provided reproducing means for reproducing the display of the fluoroscopic observation position and direction using the momentary fluoroscopic image stored in the recording means and the appearance image stored correspondingly. The structure (claim 2) can be preferably employed.

  In the present invention, as a specific configuration of the moving mechanism, the moving mechanism crosses the inspection object placed on the sample stage with a line connecting the X-ray generator and the X-ray detector. It includes a rotary table that rotates around an axis, and is configured to change the fluoroscopic observation direction by driving the rotary table. The rotary table is driven prior to fluoroscopy and continuously from a plurality of directions by the optical camera. External image storage means for storing an external appearance image of the inspection object photographed periodically or intermittently, and the observation position / direction display means is a fluoroscopic observation by rotation of the rotary table when the inspection object is viewed through X-rays. Corresponding to the change in direction, images are taken from the direction that is the same as or close to the fluoroscopic observation direction from the appearance images stored in the appearance image storage means. Configured to display the appearance image can be adopted (claim 3).

  The present invention continuously or intermittently records the temporal change of the fluoroscopic image of the object to be inspected due to the change of the fluoroscopic observation direction and the fluoroscopic observation position by the operator during actual fluoroscopic observation, and at the same time, the observation position and the observation direction. The problem is to be solved by recording the display in synchronization.

  That is, the fluoroscopic image of the inspection object displayed on the display device during actual fluoroscopic observation is recorded continuously or intermittently over time, and when the recording is reproduced, the operator's operation can be performed during actual fluoroscopic observation. Changes in the fluoroscopic image when the fluoroscopic observation direction is changed as appropriate are reproduced. It is possible to grasp the three-dimensional position and shape information such as a defect in the inspection object only by looking at such a temporal change of the fluoroscopic image. Since the display of the fluoroscopic observation position and direction at the time of observation is recorded together, the display of the fluoroscopic observation position and direction is displayed synchronously at the time of reproduction, such as a defect in the inspection object. It becomes easy to imagine the place and structure.

  Such a recording of the fluoroscopic image and the display of the fluoroscopic observation position and direction can be reproduced by a personal computer placed at an arbitrary position through a recording medium or through a line. As described above, the X-ray fluoroscopic inspection apparatus itself may be configured to have a reproduction function.

  The invention according to claim 3 embodies a moving mechanism for changing the fluoroscopic observation direction and the like, and a fluoroscopic observation position / direction display means for displaying the fluoroscopic observation position and direction. Between the line detectors, there is provided a rotary table that rotates an object to be inspected around an axis that intersects the line connecting them, and is configured so that the fluoroscopic observation direction can be changed by the rotation of the rotary table. Prior to the fluoroscopic observation, the rotating table is driven to rotate the inspection object, and the optical camera intermittently or continuously captures and stores the inspection object from a plurality of directions. Appearance image taken from the same direction or appearance image taken from the nearest direction corresponding to the rotation of the rotary table by the operator's operation, and therefore corresponding to the change of the fluoroscopic observation direction By Rukoto, the display of the perspective viewing direction. According to this configuration, there is an advantage that it is easy to grasp a three-dimensional position or the like in the entire inspection object such as a defect on a fluoroscopic image during reproduction.

  According to the present invention, the fluoroscopic image of the inspection object displayed on the display device during actual fluoroscopic observation is recorded continuously or intermittently with time, along with the display of the fluoroscopic observation position and direction. By reproducing the record, the position and structure of a defect such as a void in the inspection object can be easily grasped, and the accuracy of inspection result verification and confirmation work can be greatly improved.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a configuration diagram of an embodiment of the present invention, and is a diagram showing a perspective view showing an apparatus structure and a block diagram showing a system configuration.

  The X-ray generator 1 and the X-ray detector 2 are supported by a common support arm 3 so as to face each other. The support arm 3 is supported with respect to the column 4 via a tilting mechanism 5 and a Z stage 6. By driving the tilting mechanism 5, the X-ray generator 1 and the X-ray detector 2 are kept horizontal while maintaining an opposing state. While tilting (turning) around the axis and driving the Z stage 6, the pair of the X-ray generator 1 and the X-ray detector 2 maintains the opposite state in the same manner, and the tilting mechanism 5 and the vertical direction (z-axis direction). )

  The X-ray generator 1 generates cone-beam X-rays, and the X-ray detector 2 is a two-dimensional X-ray detector such as an FPD (flat panel detector).

  A sample stage 7 is arranged adjacent to the column 4. The sample stage 7 mounts the inspection object W and rotates around a vertical rotation axis, and moves the rotation table 8 in two axial directions (x and y axis directions) orthogonal to each other on a horizontal plane. The XY table 9 is mainly used. In performing X-ray fluoroscopy of the inspection object W, X-rays from the X-ray generator 1 are irradiated in a state where the inspection object W is mounted at a specified position on the rotary table 8. To change the fluoroscopic observation position on the inspection object W, the Z stage 6 is driven to move the pair of the X-ray generator 1 and the X-ray detector 2 in the z-axis direction, and the XY table 9 is moved in the y-axis direction. This can be done by moving. Further, the fluoroscopic observation direction can be changed by rotating the rotary table 8 and can also be performed by driving the tilting mechanism 5 and turning the support arm 3.

  A CCD camera 10 is arranged in a state of being fixed to an apparatus frame (not shown) at a position facing the column 4 with the sample stage 7 interposed therebetween. This CCD camera 10 is for photographing the inspection object W on the rotary table 8, and prior to the fluoroscopic observation of the inspection object W, the rotation table 8 is rotated through 360 °, and every fixed rotation angle. The object W is photographed intermittently. Appearance images from a plurality of directions of the inspected object W thus obtained are stored in the appearance image storage unit 23 via the control unit 22 via the image data capturing circuit 21 such as a capture board.

  Further, the output of the X-ray detector 2 is taken in through the image data taking-in circuit 24 and displayed as a live image on the display unit 25 through the control unit 22.

  The control unit 22 puts an X-ray controller 26 for controlling the tube current and tube voltage of the X-ray generator 1 described above under control, and also drives and controls the CCD camera 10. The control unit 22 is connected to an operation unit 27 including a joystick, a mouse, and a keyboard. By operating the operation unit 27, the tilt mechanism 5 and the Z stage 6 described above are connected via the axis control unit 28. Drive control signals can be supplied to the rotary table 8 and the XY table 9 to drive them arbitrarily. The operator can arbitrarily change the fluoroscopic observation position, the fluoroscopic direction, and the fluoroscopic magnification by operating the operation unit 27 during fluoroscopic observation of the inspection object W.

  The X-ray fluoroscopic image of the inspection object W is displayed on the display unit 25 as a live image as described above. For the display unit 25, an external appearance image of the inspection object W taken in advance by the CCD camera 10 is used. Thus, the fluoroscopic observation position and the fluoroscopic observation direction are displayed every moment. In this embodiment, the display content of the display 25 is stored in the display image storage unit 29 as a moving image continuously with time by operating the operation unit 27 as will be described later.

  Note that the above-described control unit 22, appearance image storage unit 23, display image storage unit 29, and the like are actually configured by a computer and its peripheral devices, and realize various functions based on installed programs. In FIG. 1, for simplification of description, each function is represented by a block.

  Now, FIG. 2 shows an example of a display mode by the display 25 according to the embodiment of the present invention. The screen of the display unit 25 includes an X-ray fluoroscopic image display area AX based on the current fluoroscopic field, and an external appearance image from a plurality of directions that is captured by the CCD camera 10 and stored in the external appearance image storage unit 23. A front appearance image display area AO1 displaying an appearance image taken from the direction closest to the fluoroscopic observation direction based on the rotation position of the turntable 8 at that time, and a right side appearance image display taken from the direction corresponding to the right side view thereof An area AO2 is set. Specifically, if the angle formed by the optical axis of the CCD camera 10 and the X-ray optical axis connecting the X-ray generator 1 and the X-ray detector 2 is, for example, 90 °, the rotary table at that time point An appearance image captured in advance at a rotation angle shifted by 90 ° with respect to the rotation angle of 8 is selected and displayed in the front appearance image display area AO1. From the appearance image displayed in the front appearance image display area AO1, the operator can grasp the perspective observation direction in the rotation direction of the rotary table 8, that is, the perspective observation direction around the z axis.

  In the front appearance image display area AO1, a mark MC representing the center of the visual field of the X-ray detector 2 at that time is displayed so as to be superimposed on the appearance image of the inspection object W. The position of this mark MC is based on the y-axis direction position of the XY table 9 when the CCD camera 10 captures the appearance image and the z-axis direction position of the Z stage 6 as a reference, and the y-axis position of the XY table 9 at that time. And a change in the z-axis position of the Z stage 6 can be determined. From this mark MC, a perspective image of the inspection object W under a high perspective magnification is displayed, and even if the perspective image is only a local part of the inspection object W, the operator has the perspective field of view to be inspected. It is possible to grasp which position of the whole object W is seen through.

  On the other hand, in the side appearance image display area AO2, an arrow mark MA indicating the fluoroscopic observation direction based on the tilt angle of the tilt mechanism 5 is displayed so as to be superimposed on the appearance image of the inspection object W. This arrow mark MA can be uniquely determined from the tilt angle of the tilt mechanism 5, and the display of this arrow mark MA allows the operator to perform the fluoroscopic observation direction in the tilt direction of the tilt mechanism 5 at that time, that is, the x-axis. It is possible to grasp the direction of fluoroscopic observation around.

  Now, on the screen of the display unit 25, a button group 30 for recording, reproducing, etc. the display screen is displayed. By operating these buttons using the mouse of the operation unit 27, the corresponding button group 30 is displayed. It is configured to perform operations. That is, the button group 30 includes a record button 31, a playback button 32, a stop button 33, a fast forward button 34, a rewind button 35, and a repeat button 36. When the recording button 31 is clicked by operating the mouse, all images displayed on the display device 25 are continuously stored in the display image storage unit 29 over time.

  When performing fluoroscopic observation of the inspection object W, the operator appropriately changes the fluoroscopic observation position and the transmission observation direction by operating the operation unit 27, for example, in order to detect defects such as voids in an aluminum die cast part as the inspection object W. When there is a defect on the perspective image at a certain point in time, the rotary table 8 is rotated in order to find position information in the direction orthogonal to the screen (position information in the X-ray fluoroscopic direction). Change the fluoroscopic observation direction and watch the transition of the position of the defect on the screen. In this operation, for example, when the fluoroscopic observation direction is changed by rotating the turntable 8, the display of the front appearance image display area AO1 and the side appearance image display area AO2 is changed from the state of FIG. ) And changes in the fluoroscopic observation direction are displayed. The position in the inspection object W can be imaged three-dimensionally from the display of the change in the fluoroscopic observation direction and the transition of the position of the defect or the like on the fluoroscopic image.

  When the recording button 31 is clicked and recording of the display screen is designated before the transmission observation operation as described above, the fluoroscopic image display area AX, the front appearance image display area AO1 and the side face appearance on the display 25 are described. The display of the image display area AO2 is taken into the display screen storage unit 29 as a moving image.

  Accordingly, by operating the playback button 32 at any time after the transmission observation operation, the display screen at the time of the transmission observation operation is reproduced as it is, and the position and structure of the defect in the inspection object W, etc. As in the case of fluoroscopic observation, a three-dimensional image can be easily obtained, which is an extremely effective tool for verifying inspection results.

  In the above embodiment, an example in which a fluoroscopic image is stored as a moving image has been shown. However, for example, it may be stored as a set of still images at a certain minute interval. Verification etc. can be performed under the same sense.

  In the above embodiment, an example in which a playback function is provided in addition to the function of recording the display screen of the display unit 25 has been described. However, the playback function is not necessarily required, and the playback of the recorded contents is not necessary. May be configured such that the recorded content is reproduced on an arbitrary personal computer using an appropriate storage medium, or the recorded content is transferred to an arbitrary personal computer via a LAN cable or the like for reproduction.

In the configuration diagram of the embodiment of the present invention, a perspective view showing the device structure and a block diagram showing the system configuration are shown together. It is explanatory drawing of the example of the display mode of the indicator in embodiment of this invention. It is explanatory drawing of the example of a change of the front external appearance image display area AO1 and the side external appearance image AO2 when rotating the turntable 8 at the time of fluoroscopic observation by embodiment of this invention.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 X-ray generator 2 X-ray detector 3 Support arm 4 Column 5 Tilt mechanism 6 Z stage 7 Sample stage 8 Rotation table 9 XY table 10 CCD camera 21, 24 Image data acquisition circuit 22 Control part 23 Appearance image memory | storage part 25 Display Device 26 X-ray controller 27 Operation unit 28 Axis control unit 29 Display image storage unit 30 Button group AX Perspective image display area AO1 Front appearance image display area AO2 Side appearance image display area

Claims (3)

A sample stage for placing an object to be inspected is arranged between an X-ray generator and an X-ray detector arranged opposite to each other, and based on the detection result of X-rays transmitted through the object to be inspected placed on the sample stage. A moving mechanism that displays a fluoroscopic image on a display and changes the fluoroscopic observation position and direction of the object to be inspected by changing the relative position of the pair of the X-ray generator and X-ray detector and the sample stage. In an X-ray inspection apparatus comprising:
An optical camera for photographing the inspection object placed on the sample stage, an appearance image of the inspection object by the optical camera, and a perspective observation position and direction of the inspection object are displayed using the appearance image. The observation position / direction display means is provided, and the fluoroscopic image of the inspection object displayed on the display is stored continuously or intermittently with time, and is displayed corresponding to the fluoroscopic image at every moment. An X-ray fluoroscopic examination apparatus comprising recording means for recording the display contents of the observation position / direction display means together.   The reproduction means for reproducing the display of the fluoroscopic observation position and the direction using the fluoroscopic image stored in the recording means and the appearance image stored correspondingly. The X-ray fluoroscopic inspection apparatus according to 1.   The moving mechanism includes a rotary table that rotates an object to be inspected arranged on the sample stage around an axis intersecting a line connecting the X-ray generator and the X-ray detector, and driving the rotary table Appearance is configured to change the fluoroscopic observation direction, and to store an external appearance image of the inspection object taken continuously or intermittently from a plurality of directions by the optical camera by driving the rotary table prior to fluoroscopy The observation position / direction display means is stored in the appearance image storage means in response to a change in the fluoroscopic observation direction due to rotation of the rotary table when the object to be inspected is X-rayed. The X-ray fluoroscopic examination according to claim 1 or 2, wherein an appearance image photographed from a direction that coincides with or is closest to the fluoroscopic observation direction is displayed from among the external appearance images that are present. Apparatus.