X-ray inspection device

Abstract

To provide an inexpensive X-ray inspection device that allows a person to peer inside a housing irradiated with X-rays without using an expensive shielding member such as lead-containing glass.SOLUTION: The inspection device inspects an article for cracking or chipping by irradiating the article with X-rays. The inspection device is provided with: a window allowing the inside to be visually recognized on a side surface of a housing where X-rays for inspection are scattered; and an X-ray shielding plate for shielding the X-rays inside the window, but allowing the inside of the housing to be peeped. The shielding plate is composed of a plurality of plate-like members, and the plate-like members are disposed inside the window at positions for shielding the X-rays leaking from the window at a predetermined interval.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to an X-ray inspection device provided with a window through which the state inside a housing where X-rays are irradiated can be seen from the outside. [Background technology]

[0002] The housing of an X-ray inspection device is designed to prevent X-rays from leaking to the outside. Therefore, if you want to see what is happening inside the housing, you need to provide a window that is sealed with leaded glass or an acrylic resin plate, as disclosed in Patent Document 1, for example.

[0003] However, the use of leaded glass or resin materials increases the cost of the equipment, and since European countries are about to ban the use of leaded glass, there is a demand for X-ray inspection equipment that can peer inside the housing without using such expensive shielding materials. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2004-125646 Summary of the Invention [Problem to be solved by the invention]

[0005] An object of the present invention is to provide an inexpensive X-ray inspection device that allows viewing into the housing where X-rays are irradiated without using an expensive shielding member. [Means for solving the problem]

[0006] An X-ray inspection apparatus according to one aspect of the present invention comprises: a housing having a window through which an operator can view the inside; a conveying unit that conveys an article into the housing; an X-ray irradiation unit in the housing that irradiates the object with X-rays; an X-ray detection unit that detects X-rays that have passed through the article; an inspection unit that inspects the item based on the detection result of the X-ray detection unit; an X-ray shielding plate that blocks the X-rays leaking to the outside through the window of the housing, The X-ray shielding plate is composed of a plurality of plate-shaped members, each of which is located inside the window and spaced at a predetermined interval in a position to block X-rays leaking from the window.

[0007] This allows the inside of the housing to be seen through the gaps between the plate-like members arranged at predetermined intervals, and also prevents scattered X-rays inside the housing from leaking out through the window, making it possible to provide an inexpensive X-ray inspection device to the market.

[0008] In the X-ray inspection device according to one aspect of the present invention, the plurality of plate-like members may be arranged so as to intersect with the direction of travel of the X-rays irradiated from the X-ray irradiation unit toward the window, and at least a portion of adjacent plate-like members may overlap each other when viewed from the direction of travel of the X-rays.

[0009] This allows the plate-like members arranged at predetermined intervals to prevent scattered X-rays within the housing from leaking to the outside, while allowing the inside of the housing to be seen through the gaps between the plate-like members.

[0010] In the X-ray inspection apparatus according to one aspect of the present invention, the width of the plate-like members may be wider than the predetermined interval. Thus, if wider plate-like members are used, the interval between the plate-like members can be increased accordingly. Therefore, for example, by appropriately selecting the width of the plate-like members and the interval between the plate-like members, the field of view for viewing inside the housing through the interval can be increased.

[0011] The X-ray inspection apparatus according to one aspect of the present invention may include a sorting unit downstream of the transport unit that sorts the items based on the inspection results, and the window may be located to the side of the sorting unit.

[0012] When using a sorting unit, it is necessary to actually run known defective products through the sorting unit to check whether they can be reliably sorted by the sorting unit. In the X-ray inspection device according to one aspect of the present invention, the window is disposed on the side of the sorting unit, so that the sorting timing can be adjusted while checking the sorting operation of the sorting unit through the window.

[0013] In the X-ray inspection apparatus according to one aspect of the present invention, the plate members are configured to be movable along the transport direction, thereby making it possible to adjust the intervals between the plate members.

[0014] In the X-ray inspection device according to one aspect of the present invention, the plate-like member is configured to be rotatable about a vertical axis, so that by facing the plane of the plate-like member toward a sorting unit or the like in the housing that one wishes to check, one can check the operation of the sorting unit or the state of the object to be inspected. [Effects of the Invention]

[0015] According to one aspect of the X-ray inspection device of the present invention, it is possible to provide an inexpensive X-ray inspection device that can peer into the housing without using a window blocked with an expensive shielding member and without allowing X-rays to leak. [Brief explanation of the drawings]

[0016] [Figure 1] 1 is a front view of an embodiment of an X-ray inspection device according to the present invention; [Figure 2] FIG. 2 is an external perspective view of the X-ray inspection device with the inside of the housing exposed. [Figure 3] FIG. 2 is a perspective view showing the appearance of an X-ray shielding plate, illustrating the structure of a window that blocks X-rays. [Figure 4] FIG. 4(a) is a perspective view showing the appearance of one plate-like member that constitutes the X-ray shielding plate, and FIG. 4(b) is an enlarged perspective view of the circled portion shown in FIG. 4(a). [Figure 5] FIG. 10 is a schematic plan view of plate-like members arranged at predetermined intervals. [Figure 6] FIG. 10 is a schematic plan view of a plate-shaped member in which the width of the plate-shaped member is increased and the interval between the plate-shaped members is widened. [Figure 7] FIG. [Figure 8] FIG. 1 is a functional block diagram of an X-ray inspection device. DETAILED DESCRIPTION OF THE INVENTION

[0017] An embodiment of the present invention will be described below with reference to the drawings. However, this embodiment does not limit the technical scope of the present invention. In addition, in the description of the drawings, identical or similar parts are designated by the same or similar reference numerals. However, the drawings are schematic, and the ratios of dimensions, etc., differ from those of the actual product. In addition, in this specification and drawings, elements having substantially the same function and configuration are designated by the same reference numerals, and elements not directly related to the present invention are not shown.

[0018] Fig. 1 shows a front view of the X-ray inspection device 10, and Fig. 2 shows an external perspective view with the inside of the housing 1 of the X-ray inspection device 10 partially exposed. In these figures, the X-ray inspection device 10 inspects, for example, packaged candies for cracks, chips, and foreign matter, but the objects to be inspected are not limited to packaged candies and can be applied to a variety of items.

[0019] This X-ray inspection device 10 includes a transport unit 2 that transports an item M (inspection object) into the housing 1, an X-ray irradiation unit 3 that irradiates the item M with X-rays within the housing 1, an X-ray detection unit 4 that detects the X-rays that have passed through the item M, an inspection unit 5 (see Figure 8) that inspects the item M for cracks, chips, etc. based on the detection results of the X-ray detection unit 4, a window 6 for viewing inside the housing 1, an X-ray shielding plate 7 that blocks X-rays that leak out of the housing 1 through the window 6, a sorting unit 8 that sorts items into good and bad products based on the inspection results of the inspection unit 5, and a touch panel 9 that operates the X-ray inspection device 10.

[0020] The housing 1 is a structure in which the internal space is enclosed by stainless steel material that blocks X-rays, and is equipped with a protective cover 1a on the entrance side, a central body 1b with an opening / closing door D, and a protective cover 1c on the exit side.

[0021] The entrance-side protective cover 1a is tunnel-shaped with openings on both sides, and a protective curtain (not shown) is hung from the entrance on the right side. The exit-side protective cover 1c is box-shaped with openings on the bottom and the surface that contacts the central body 1b, and inspected items M are discharged from the opening on the bottom side of the protective cover 1c through the sorting section 8.

[0022] The transport section 2 is composed of a first transport section 2a covered by a protective cover 1a on the entrance side, a second transport section 2b inside the central body 1b, and a chute 2c connecting these transport sections 2a and 2b. Both transport sections 2a and 2b are composed of belt conveyors, and the transport surface of the first transport section 2a is located one step higher than the transport surface of the second transport section 2b. Therefore, the downwardly sloping chute 2c located between the two transport sections 2a and 2b is attached in a floating state without contacting the transport surfaces of the two transport sections 2a and 2b. The belt receiver that supports the backside of the endless belt of the second transport section 2b has a slit in the direction perpendicular to the transport direction (width direction) at the central position where X-rays are irradiated, and the X-ray detection unit 4 is located widthwise along the slit.

[0023] An X-ray irradiation unit 3 is installed in the upper part of the central body 1b, and an X-ray detection unit 4 is installed in the hollow part surrounded by the travel path of the endless belt of the second conveyor unit 2b. The X-ray irradiation unit 3 is composed of an X-ray source (not shown) located behind the touch panel 9, and a collimator that focuses the X-rays emitted from the X-ray source into a fan-shaped beam and irradiates the X-ray detection unit 4. The X-ray detection unit 4 is also composed of a line sensor arranged in the width direction perpendicular to the conveying direction of the second conveyor unit 2b. The line sensor includes a photodiode and a scintillator placed on top of it, and is configured to convert X-rays that have passed through the article M and the endless belt into an electrical signal and output it.

[0024] A window 6 is provided on the front side of the protective cover 1c on the exit side, and a sorting unit 8 is located inside the protective cover 1c, which sorts items that have an NG inspection result. The window 6 is located in a position where the sorting operation of the sorting unit 8 can be confirmed. The sorting timing of the sorting unit 8 varies depending on the conveying speed of the items M and the timing of the output of the inspection results from the inspection unit 5, so before starting operation, it is necessary to run a known defective item through the window 6 and check whether it is being properly sorted. Then, if the sorting timing is off, the sorting timing of the sorting unit 8 is adjusted while checking the sorting operation through the window 6.

[0025] As shown in Fig. 3, an X-ray shielding plate 7 that blocks X-rays leaking from the window 6 is attached to the inside of the window 6. The window 6 is made up of a stainless steel frame 61, and a circular opening 62 is formed on the front side, with the X-ray shielding plate 7 attached to the back (rear side) of the opening 62. The X-ray shielding plate 7 is made up of a plurality of rectangular plate-like members 71 that are also made of stainless steel, and these plate-like members 71 are arranged in the left-right direction at predetermined intervals to prevent X-ray leakage.

[0026] Longitudinal elongated holes 62 are formed in the top and bottom surfaces of the framework 61, and bolts 63 are inserted into the elongated holes 62 and connected to the top and bottom ends of each plate-like member 71, thereby fixing each plate-like member 71 to the framework 61. Note that although only two heads of the bolts 63 are shown in FIG. 3 and the heads of the other bolts 63 are omitted, a bolt 63 is attached to the top and bottom of each plate-like member 71 corresponding to it. The bolts 63 inserted into the elongated holes 62 are movable along the elongated holes 62, and as will be described later, the bolts 63 can be moved along the elongated holes 62 while connected to the plate-like members 71, and when a nut is screwed onto the bolt 63 and tightened at an appropriate position, the plate-like members 71 can be fixed to the framework 61.

[0027] FIG. 4(a) shows a perspective view of the appearance of plate-shaped member 71, and FIG. 4(b) is an enlarged perspective view of the circled end in FIG. 4(a) rotated 90 degrees. In these figures, plate-shaped member 71 has a rectangular main body 72 extending vertically and upper and lower end portions 73 extending horizontally. The upper and lower end portions 73 are formed by bending both ends of main body 72 into an L-shape. Before bending, both ends 73 of main body 72 have perforated openings 75, leaving semicircular tongues 74. When end portions 73 connected to main body 72 on both sides of tongue 74 are bent into an L-shape along widthwise fold line L passing through the center line of circular hole 76 in the center of tongue 74, end portions 73 are bent horizontally, and consequently tongue 74 tilts horizontally, so that vertical line V of main body 72 coincides with the center of circular hole 76 in tongue 74.

[0028] The round holes 76 of the tongue pieces 74 are holes through which the bolts 63 shown in Figure 3 are inserted. After inserting the plate-shaped members 71 between the upper and lower surfaces of the frame 61, the round holes 76 and the long holes 62 are aligned, and the bolts 63 are inserted toward the round holes 76. Then, nuts (not shown) are screwed onto the inserted bolts 63 to tighten them, so that both end portions 73 of each plate-shaped member 71 are fixed to the upper and lower surfaces of the frame 61.

[0029] Furthermore, when the bolts 63 are loosened and moved along the elongated holes 62, the spacing between the plate-shaped members 71 can be adjusted. Furthermore, when the plate-shaped members 71 are rotated about a vertical line V passing through the axes of the upper and lower bolts 63, the orientation of the plate-shaped members 71 can be changed. When changing the orientation of the plate-shaped members 71, it is necessary to adjust the spacing between the plate-shaped members 71 in accordance with the width of the plate-shaped members 71 so that scattered X-rays within the housing 1 do not leak to the outside through gaps between adjacent plate-shaped members 71. When changing the width of the plate-shaped members 71, it is preferable to extend one side 72a of the main body 72 in the width direction and leave the other side 72b as is.

[0030] 5 and 6 show plan views of plate-like members 71 arranged so that X-rays do not leak from the gaps d between them. In particular, Fig. 5 shows an example in which multiple plate-like members 71 of the same width are used, and they are arranged at equal intervals d so that they face in a direction perpendicular to the conveying direction F of the article M. Fig. 6 also shows an example of the intervals d between plate-like members 72 when plate-like members 72 of different widths are used and they are arranged with their orientations slightly changed.

[0031] Within the housing 1 in Figure 5, the source of scattered X-rays is the X-ray irradiation region R. Of the X-rays that leave this region R, the X-ray with the largest incident angle α to the window 6 is X-ray B, which is emitted from the rearmost X-ray irradiation point P. As the irradiation direction of this X-ray B shifts to the left, the angle of incidence of the X-ray to the window 6 gradually decreases. Therefore, as shown in Figures 5 and 6, if this X-ray B is represented by a dashed dotted line, and the right-hand plate-like member 72 of two plate-like members 72 spaced apart by a predetermined distance d blocks X-ray B, it will not pass through the distance d between the plate-like members 72. In this case, if the width of the right-side plate-like member 72, i.e., the length in the front-to-rear direction, is short, X-rays B will leak, but if the width is long, X-rays B will not leak, so if the distance d between two adjacent plate-like members 72 and the width and orientation of the plate-like member 72 on the right are set appropriately, X-rays B will not leak. The width, distance d, and orientation of each plate-like member 72 are determined under these conditions.

[0032] The sorting section 8 sorts out good products and defective products based on the inspection results of the inspection section 5. In this embodiment, as shown in FIG. 7, if the inspection result is a good product, the good product M1 discharged from the second conveying section 2b is transported downstream via a chute 81 and a slider 82, and if the inspection result is a defective product M2, the chute 81 is lifted up and the defective product M2 discharged from the second conveying section 2b is dropped into a collection box 83 shown in FIG. 2 for collection.

[0033] Specifically, a bracket 84 is attached to the bottom surface of the chute 81, and the chute 81 and bracket 84 are configured to swing up and down around a horizontal shaft 85 attached to the bracket 84. An air cylinder 86 is used as the actuator, and when a piston 87 connected to the bracket 84 extends, the chute 81 jumps up, and when the piston 86 retracts into the cylinder, the chute 81 returns to its initial position, and operates to send the non-defective product M1 to the slider 82.

[0034] 8 shows a block diagram of the control system of the X-ray inspection apparatus 10. In this diagram, the inspection section 5 is made up of a control unit made up of a microcomputer, and is electrically connected to the touch panel 9, transport section 2, X-ray irradiation section 3, X-ray detection section 4, and sorting section 8, and is programmed to drive and control these.

[0035] The touch panel 9 allows the user to start and stop the X-ray inspection device 10 and set the necessary operating and inspection conditions by operating the screen displayed on the liquid crystal display. Furthermore, on the initial screen before operation starts, the speed of the transport unit 2 and the X-ray intensity of the X-ray irradiation unit 3 can be set. Furthermore, after operation starts, a screen for adjusting the sorting timing of the sorting unit 8, for example, is displayed.

[0036] Although one embodiment has been described above, the present invention is not limited to this embodiment, and other embodiments are also possible. For example, a sorting device may be used in which a third conveyor is connected to the exit side of the second conveyor 2b, and an arm that swings on the conveying surface is attached to the side of the third conveyor, and defective products conveyed from the second conveyor 2b are discharged to the side in the conveying direction by the arm. Also, a drop-type belt conveyor may be disposed at the exit side of the second conveyor 2b. In this case, the swinging fulcrum of the belt conveyor is disposed adjacent to the exit side of the second conveyor 2b. Also, a protective curtain is hung at the exit side of the second conveyor 2b.

[0037] Furthermore, in the above-described embodiment, each plate-like member 72 is configured to be able to rotate individually around the vertical line V passing through the central axis of the bolt 63, but each plate-like member 72 may be connected by a common link mechanism so that by operating the link mechanism, the orientation of each plate-like member 72 changes simultaneously. In this case, the movable range of the link mechanism may be limited so that the X-ray irradiation region R is not visible through the gaps d between each plate-like member 72.

[0038] In addition, in the above embodiment, the upper and lower ends 73 of the plate-shaped member 72 are movably fixed to the long holes 62 of the frame-shaped frame 61, but only the upper end 73 of the plate-shaped member 72 may be fixed to the long holes 62 of the frame-shaped frame 61. [Explanation of symbols]

[0039] 1 chassis 2. Conveyor section 3 X-ray irradiation section 4 X-ray detection unit 5. Inspection Department 6. Windows 7 X-ray shielding plate 72 Plate-shaped members 8 Sorting section d-spacing M Goods

Claims

1. a housing having a window through which an operator can view the inside; a conveying unit that conveys an article into the housing; an X-ray irradiation unit configured to irradiate the object with X-rays within the housing; an X-ray detection unit that detects X-rays that have passed through the article; an inspection unit that inspects the item based on the detection result of the X-ray detection unit; an X-ray shielding plate that blocks the X-rays leaking to the outside through the window of the housing, an X-ray inspection device, wherein the X-ray shielding plate is composed of a plurality of plate-shaped members, each of which is located inside the window and spaced a predetermined distance apart in a position to block X-rays leaking from the window.

2. 2. The X-ray inspection device according to claim 1, wherein the plurality of plate-shaped members intersect with a direction of travel of the X-rays irradiated from the X-ray irradiation unit toward the window, and at least a portion of adjacent plate-shaped members overlap each other when viewed from the direction of travel of the X-rays.

3. The width of the plate-like member is wider than the predetermined interval.

3. The X-ray inspection apparatus according to claim 1 or 2.

4. a sorting section downstream of the conveying section that sorts the articles based on the inspection results, and the window is located to the side of the sorting section; 3. The X-ray inspection apparatus according to claim 1 or 2.

5. The plate-like member is movable along the conveying direction.

3. The X-ray inspection apparatus according to claim 1 or 2.

6. The plate-like member rotates around a vertical axis.

3. The X-ray inspection apparatus according to claim 1 or 2.

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