JP2013002936A - Conveyance structure for object to be irradiated - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely shield radiation which is generated on the basis of electron beams, and to reduce an area for installing a conveyance structure which shields an electron beam irradiation device.SOLUTION: A conveyance structure 200 comprises: an electron beam irradiation device 100; an irradiation region R which is provided on a conveyance passage 350 partitioned with a wall surface; a first passage 352 which constitutes a part of the conveyance passage; a second passage 354 which has a height in a perpendicular direction different from that of the first passage and is positioned in a distance from the irradiation region longer than that of the first passage; a first elevating passage 370 which connects the first passage and the second passage; and a shield section 330 which is provided at least either on a wall surface partitioning the first passage or on a wall surface partitioning the first elevating passage and shields the straight incidence of radiation from the first passage to the second passage.

Description

  The present invention relates to a transport structure for an object to be irradiated using an electron beam irradiation apparatus that irradiates the object to be irradiated with an electron beam.

  Conventionally, electron beam irradiation apparatuses (for example, Patent Documents 1 and 2) used in various fields such as sterilization of medical instruments and foods, cross-linking and curing of resins, and removal of lesions such as malignant tumors are known. Yes. Such an electron beam irradiation apparatus is equipped with a cathode electrode and an accelerator. By supplying electric power to the cathode electrode, the electron beam is emitted from the cathode electrode, and the electron beam is accelerated by the accelerator to irradiate the irradiated object. To do.

  When an electron beam collides with the irradiated object or the like in an irradiation region where the irradiated object is irradiated with an electron beam, radiation such as X-rays is generated. Therefore, the electron beam irradiation device is surrounded by the shielding wall so that the generated radiation does not leak outside. Here, the shielding wall is made of concrete or metal (lead or stainless steel) having a thickness that can sufficiently shield the generated radiation. Further, the shielding wall surrounds the electron beam irradiation device and also has a function as a building.

  On the other hand, in order to efficiently irradiate an irradiated object with an electron beam, the irradiated object is often continuously transferred to an irradiation region by a transfer device such as a conveyor. Therefore, in order to prevent the leakage of radiation to the outside through the conveyance path in which the conveyance device is installed, the shielding wall is formed so that the conveyance path forms a maze structure.

JP 2001-349998 A JP 2003-139898 A

  11 is a plan view for explaining the entire image of the conventional electron beam irradiation system 10, FIG. 12 is a sectional view taken along line XII-XII in FIG. 11, and FIG. 13 is a sectional view taken along line XIII-XIII in FIG. FIG.

  As shown in FIGS. 11 to 13, the electron beam irradiation system 10 is configured to include a building 20 composed of a floor portion 12 and a shielding wall 14 formed of concrete or the like. A transport device 40 that transports the irradiated object W in the horizontal direction and an electron beam irradiation device 50 that irradiates the irradiated object W transported by the transport device 40 with an electron beam are installed.

  More specifically, the building 20 accommodates the electron beam irradiation device 50 in the center and the irradiation path 22 extending linearly in the horizontal direction and the irradiated object W from the carry-in entrance 24a. Communication passage 26b, the communication passage 26 communicating the carry-in passage 24b and the irradiation passage 22, the unloading passage 28b for unloading the irradiated object W to the unloading port 28a, and the communication communicating the irradiation passage 22 and the unloading passage 28b. It is formed so as to be partitioned into a passage 30 and a power supply chamber 32 that houses a high-frequency power supply device 52 that supplies power to the electron beam irradiation device 50.

  As shown in FIGS. 12 and 13, in the electron beam irradiation system 10, when the electron beam irradiation device 50 is installed so as to irradiate the electron beam vertically downward, the electron beam irradiation device 50 is positioned vertically below the electron beam irradiation device 50. Radiation is generated by the electron beam colliding with the irradiation object W, the transport device 40 and the floor 12. In other words, a region (irradiation region) R below the electron beam irradiation apparatus 50 is a radiation generation source. And the radiation | emission direction of the radiation from the irradiation area | region R reaches 360 degree | times.

  When radiation collides with a wall, the radiation after the collision is roughly divided into radiation that passes through the wall (transmitted radiation), radiation that is absorbed by the wall (absorbed radiation), and radiation that is reflected by the wall (reflected radiation). The

  Therefore, for transmitted radiation and absorbed radiation, the right wall 14 a, the left wall 14 b, the front wall 16 a, and the electron beam irradiation device 50, in the shielding wall 14, in which the radiation with the highest dose generated in the irradiation region R is linearly incident. Leakage to the external E is blocked by forming the ceiling wall 18 positioned above to a thickness that prevents radiation from being transmitted (absorbed) to the external E. The radiation with the highest dose of radiation enters the intermediate wall 16b that partitions the irradiation passage 22 and the power supply chamber 32, but the back wall 16c that partitions the power supply chamber 32 is interposed between the intermediate wall 16b and the outside E. Therefore, the sum of the horizontal thickness of the intermediate wall 16b and the back wall 16c is formed to be equal to the thickness of the right side wall 14a and the like.

  Here, since the radiation incident on the side walls 14c, 14d, and 14e is reflected radiation reflected by the right side wall 14a and the left side wall 14b, the dose is smaller than the radiation generated in the irradiation region R. Therefore, as shown in FIG. 11, the horizontal thickness of the side walls 14c, 14d, and 14e can be made shorter by the length L than the right side wall 14a and the left side wall 14b.

  As for the reflected radiation, when the energy of the electron beam irradiated from the electron beam irradiation device 50 is, for example, about 10 MeV, the reflected radiation is reflected at least three times from the irradiation region R, and the dose of the reflected radiation is made sufficiently small to the external E. It needs to be reached. Accordingly, the irradiation passage 22, the carry-in passage 24b, the communication passage 26, and the carry-out passage 28b are so reflected that the radiation generated in the irradiation region R is reflected at least three times such as the reflection points T1, T2, and T3 and reaches the outside E. A communication passage 30 is provided.

  As described above, in order to block the transmission of the radiation with the highest dose generated in the irradiation region R to the outside E, the irradiation passage 22 in which the irradiation region R is located has other walls (side walls 14c, 14d, 14e). It is necessary to be surrounded by thick walls (right side wall 14a, left side wall 14b, front wall 16a), but other passages (loading path 24b, communication path 26, discharge path 28b, communication path 30) are surrounded. Compared to the walls (side walls 14c, 14d, 14e), the installation area is increased by a length of 2L.

  Therefore, the place where the electron beam irradiation system 10 is installed may be limited, and it is desired to develop the electron beam irradiation system 10 that further reduces the installation area while reliably preventing leakage of radiation to the external E. ing.

  Therefore, in view of such problems, the present invention can reliably shield the radiation generated based on the electron beam irradiated by the electron beam irradiation device by devising the conveyance path, and the electron beam irradiation device. The object of the present invention is to provide an object transportation structure that can reduce the installation area (occupied area) of the transportation structure that shields the object.

  In order to solve the above-described problems, an object to be irradiated transport structure according to the present invention is provided on an electron beam irradiation device that irradiates an electron beam to the object to be irradiated, and a transport path that is partitioned by a wall surface. The irradiation area is an area where an electron beam is irradiated to the irradiated object, and the irradiation area is an area where radiation is generated based on the electron beam, and the irradiation object is placed from the carry-in portion to the irradiation area. Carrying in and carrying out the irradiated object from the irradiation area to the carry-out unit, the first passage constituting a part of the conveyance passage, the height of the first passage in the vertical direction is different from that of the first passage, and irradiation is performed. A second passage located at a distance from the region farther than the first passage, an elevating passage connecting the first passage and the second passage, a wall surface defining the first passage, and elevating Provided on at least one of the walls that define the passage , Characterized in that a shielding unit for shielding the straight incidence of radiation from the first passage to the second passage.

  The irradiation area may be provided in the first passage.

  The first passage may be located vertically below the second passage.

  The electron beam irradiation apparatus may irradiate the electron beam vertically downward.

  The shielding portion is a ceiling wall surface that defines the first passage, and is arranged on a straight line connecting a radiation source in the irradiation region and an end portion on the irradiation region side of the bottom surface that defines the second passage. The ceiling wall of the passage may be located.

  One end side of the first passage is connected to the second passage through the lifting passage, and the other end side of the first passage is connected to the first passage and the second passage through the other lifting passage. You may connect to the channel | path different from a channel | path.

  The transport passage may be configured to include a third passage having a height equal to that of the second passage in the vertical direction and perpendicular to the second passage and the horizontal direction.

  According to the present invention, by devising the transport path, radiation generated based on the electron beam irradiated by the electron beam irradiation device can be reliably shielded, and the transport structure for shielding the electron beam irradiation device is provided. It is possible to reduce the installation area.

It is an external appearance perspective view of an electron beam irradiation apparatus. It is the figure which looked at the electron beam irradiation apparatus from the Z-axis direction in FIG. It is a top view for demonstrating the whole image of a conveyance structure. It is IV-IV sectional drawing in FIG. It is VV sectional drawing in FIG. It is explanatory drawing for demonstrating a conveyance path | route. It is explanatory drawing for demonstrating an example of an raising / lowering apparatus. It is explanatory drawing for demonstrating the emission direction of the radiation which generate | occur | produced in the irradiation area | region. It is explanatory drawing for demonstrating reflection of the radiation which generate | occur | produced in the irradiation area | region. It is explanatory drawing for demonstrating the other example of a shielding part. It is a top view for demonstrating the whole image of the conventional electron beam irradiation system. It is XII-XII sectional drawing in FIG. It is XIII-XIII sectional drawing in FIG.

  Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings. The dimensions, materials, and other specific numerical values shown in the embodiments are merely examples for facilitating the understanding of the invention, and do not limit the present invention unless otherwise specified. In the present specification and drawings, elements having substantially the same function and configuration are denoted by the same reference numerals, and redundant description is omitted, and elements not directly related to the present invention are not illustrated. To do.

(Electron beam irradiation apparatus 100)
1 is an external perspective view of the electron beam irradiation apparatus 100, and FIG. 2 is a view of the electron beam irradiation apparatus 100 viewed from the Z-axis direction in FIG. In FIG. 1, a support mechanism for supporting the electron beam irradiation apparatus 100 is omitted for easy understanding.

  As shown in FIGS. 1 and 2, the electron beam irradiation apparatus 100 includes an electron gun 110, a high frequency power source 112, a waveguide 114, a prebuncher 116, an accelerator 118, and a scan horn 120. ing. The electron gun 110, the prebuncher 116, the accelerator 118, and the scan horn 120 are continuous in an internal space (vacuum chamber). The internal space is changed from a high vacuum state to an ultrahigh vacuum state by a vacuum pump 102 such as an ion pump. (For example, 10E-5 Pa or less).

  In the electron beam irradiation apparatus 100, the thermoelectrons emitted from the electron gun 110 are accelerated by the prebuncher 116 and the accelerator 118, pass through the scan horn 120, and travel toward the irradiation object W transported in the transport path 350. 1 is irradiated in the Y-axis direction. Hereinafter, each functional unit of the electron beam irradiation apparatus 100 will be described in detail.

(Electron gun 110)
The electron gun 110 is, for example, a triode electron gun, and heats the cathode electrode with electric power supplied from a cathode power supply (AC power supply) 104, and the high voltage grid voltage (extraction voltage) applied in a pulsed manner causes electrons to be emitted. Release the line.

(High-frequency power source 112, waveguide 114)
The high-frequency power source 112 is configured by a klystron or the like, and supplies, for example, 3 GHz pulsed high-frequency power corresponding to the S band to the prebuncher 116 and the accelerator 118 through the waveguide 114. The waveguide 114 supplies a high-frequency voltage supplied from the high-frequency power source 112 to the accelerator 118 through RF windows 114a and 114b made of ceramic or the like. An insulating gas such as sulfur hexafluoride (SF ₆ ) is filled between the RF window 114 a and the RF window 114 b in the waveguide 114, and the waveguide 114 is discharged by the voltage output from the high-frequency power source 112. Avoid the situation. The RF windows 114a and 114b serve as boundaries that separate the SF ₆ and the vacuum.

(Prebuncha 116)
The prebuncher 116 is provided between the electron gun 110 and the accelerator 118, and is connected to the high frequency power source 112 through the waveguide 114. The prebuncher 116 bunches the electron beam incident from the electron gun 110 (density compression (velocity modulation)) and sends the electron beam to the accelerator 118. More specifically, a high-frequency electric field is formed in the prebuncher 116 by a high-frequency voltage supplied from the high-frequency power source 112, and the electron beam that has passed through the prebuncher 116 is bunched and enters the accelerator 118. By bunching the electron beam with the prebuncher 116, the dispersion of the energy of the electron beam accelerated by the accelerator 118 can be reduced, and the uniformity of the energy of the electron beam can be improved.

  Here, the electron beam is efficiently accelerated by the accelerator 118 only when the incident timing of the electron beam compressed by the prebuncher 116 to the accelerator 118 is synchronized with the high-frequency positive phase in the accelerator 118. Therefore, in order to adjust the incident timing of the electron beam from the prebuncher 116 to the accelerator 118, the high frequency introduction unit 116a of the prebuncher 116 is provided with a phase adjusting unit (not shown). In addition, since the compression rate of the electron beam (the length of the bunched electron beam) also affects the acceleration efficiency by the accelerator 118, that is, the shorter the electron beam length, the higher the acceleration efficiency. Therefore, in order to adjust the length of the electron beam by adjusting the strength of the high frequency to be supplied, the high frequency introducing section 116a of the prebuncher 116 is provided with an attenuation (attenuator) means (not shown).

(Accelerator 118)
The accelerator 118 is made of stainless steel (for example, SUS) or the like, and has a plurality of acceleration spaces inside. When a high-frequency voltage (for example, 3 GHz) is supplied from the high-frequency power source 112, the plurality of acceleration spaces of the accelerator 118 function as a spatial resonator, and an electric field that changes with time is generated in the spatial resonator. Then, the electron beam compressed by the prebuncher 116 is accelerated by this time-varying electric field.

  Here, the frequency of the voltage supplied from the high-frequency power supply 112 and the distance of the acceleration space are designed so that the speed of the electron beam and the timing of positive charging (becomes a positive phase) in the acceleration space are synchronized. The electron beam is gradually accelerated in the accelerator 118, and finally accelerated to, for example, about 10 MeV and is incident on the scan horn 120.

  In this case, a standing wave type linear accelerator is used as the accelerator 118. However, a traveling wave type linear accelerator or a circular accelerator such as a synchrotron or a cyclotron is used as long as electrons can be accelerated. You can also

(Scan horn 120)
The internal space of the scan horn 120 is connected to the accelerator 118, the scan electromagnet 122 provided near the exit of the accelerator 118, and the electron beam extraction part 124 provided at the end facing the end connected to the accelerator 118. (See FIGS. 1 and 2).

  The scanning electromagnet 122 scans (scans) the electron beam incident from the accelerator 118 in the horizontal direction (X-axis direction in FIG. 1). Since the traveling direction of the electron beam is the vertical direction (Y-axis direction in FIG. 1), the scanning electromagnet 122 scans the electron beam traveling in the vertical direction in the horizontal direction, so that the irradiated object W having a width in the horizontal direction. It is possible to reliably irradiate an electron beam.

  The electron beam extraction part 124 is made of, for example, a Ti foil having a thickness of about 50 μm and serves as a boundary that separates the internal space from the atmosphere. The electron beam extracted from the electron beam extraction unit 124 to the atmosphere is irradiated to the irradiation object W.

  In this way, the electron beam emitted by the electron gun 110 is accelerated by the accelerator 118 and is irradiated to the irradiation object W through the electron beam extraction unit 124.

  By the way, in the irradiation area | region R where the to-be-irradiated object W is irradiated with an electron beam, an electron beam collides with the to-be-irradiated object W, the conveying apparatus which conveys the to-be-irradiated object W, and the floor part in which a conveying apparatus is installed. If it does so, a radiation will generate | occur | produce from the location which the electron beam collided. Therefore, it is necessary to surround the electron beam irradiation apparatus 100 with a shielding wall so that the generated radiation does not leak outside.

  Hereinafter, the transport structure 200 that prevents leakage of radiation generated based on the electron beam irradiation by the electron beam irradiation apparatus 100 to the outside will be described in detail.

(Conveying structure 200)
3 is a plan view for explaining the entire image of the transport structure 200, FIG. 4 is a sectional view taken along line IV-IV in FIG. 3, and FIG. 5 is a sectional view taken along line VV in FIG. In FIG. 3, the ceiling wall is not shown for easy understanding.

  As shown in FIGS. 3 to 5, the transport structure 200 includes an electron beam irradiation apparatus 100 (in FIGS. 3 to 5, an electron beam irradiation unit 150 including an electron gun 110, a prebuncher 116, an accelerator 118, and a scan horn 120. , A high frequency power source 112 and a waveguide 114), a building 300, and a transport device 400 that transports the irradiated object W.

  The building 300 is made of concrete or the like, and includes a floor portion 310, a shielding wall 312, and a ceiling wall 314. Inside the building 300, an electron beam irradiation device 100, a power supply chamber 302 that accommodates the high frequency power source 112 of the electron beam irradiation device 100, a transfer passage 350, and a transfer device 400 installed in the transfer passage 350 are provided. . The power supply chamber 302 and the transfer passage 350 are partitioned by the wall surface of the floor portion 310, the shielding wall 312 and the ceiling wall 314.

  FIG. 6 is an explanatory diagram for explaining the conveyance path 350. As shown in FIG. 6, the conveyance passage 350 includes a first passage 352, a second passage 354a, 354b, a third passage 356a, 356b, a fourth passage 358a, 358b, a fifth passage 360a, 360b, Sixth passages 362a and 362b, first elevating passages 370a and 370b, and second elevating passages 372a and 372b are configured.

  In the present embodiment, the first passage 352, the fifth passage 360a, 360b, the sixth passage 362a, 362b are provided on the first floor (ground level), the second passage 354a, 354b, the third passage 356a, 356b, The four passages 358a and 358b are provided on the second floor whose height in the vertical direction is higher than the ground level. Accordingly, the first elevating passage 370a functions to connect the first passage 352 on the first floor and the second passage 354a on the second floor. The first elevating passage 370b serves to connect the first passage 352 on the first floor and the second passage 354b on the second floor. The second lift passage 372a functions to connect the fifth passage 360a on the first floor and the fourth passage 358a on the second floor. The second elevating passage 372b functions to connect the fifth passage 360b on the first floor and the fourth passage 358b on the second floor.

  In the first floor portion, the fifth passages 360 a and 360 b are parallel to the first passage 352. In the first floor portion, the fifth passage 360a and the sixth passage 362a are provided to be orthogonal to the horizontal direction, and the fifth passage 360b and the sixth passage 362b are provided to be orthogonal to the horizontal direction. In the second floor portion, the third passage 356a is provided to be orthogonal to the second passage 354a in the horizontal direction, and the third passage 356b is provided to be orthogonal to the second passage 354b in the horizontal direction. In the second floor portion, the fourth passages 358a and 358b are parallel to the second passages 354a and 354b. In the second floor portion, the second passage 354a and the third passage 356a are provided to be orthogonal to the horizontal direction, and the second passage 354b and the third passage 356b are provided to be orthogonal to the horizontal direction.

  In the present embodiment, since the electron beam irradiation unit 150 is provided at the center of the first passage 352, the irradiation region R is located in the first passage 352, and the second passages 354a and 354b are connected to the irradiation region R from the irradiation region R. The distance is located at a distance farther than the first passage 352.

  The transfer device 400 is installed in the transfer passage 350, and as shown by the white arrow in FIG. 6A, the sixth passage 362a, the fifth passage 360a, the second elevating passage 372a, the second passage 372a from the carry-in portion 376a. The irradiated object W is carried into the irradiation region R of the first passage 352 through the four passages 358a, the third passage 356a, the second passage 354a, and the first elevating passage 370a. The transfer device 400 then irradiates the irradiated object W irradiated with the electron beam in the irradiation region R with the first passage 352, the first elevating passage 370b, the second passage 354b, the third passage 356b, the fourth passage 358b, and the second passage. It is carried out to the carry-out part 376b through the up-and-down passage 372b, the fifth passage 360b, and the sixth passage 362b.

  The conveyance apparatus 400 is comprised with a conveyor, for example, mounts the to-be-irradiated object W on a conveyor, and conveys it. In addition, the direction switching portion in the transfer device 400, specifically, the connection portion between the second passage 354a and the third passage 356a, the connection portion between the second passage 354b and the third passage 356b, the third passage 356a and the fourth passage. 358a, the third passage 356b and the fourth passage 358b, the fifth passage 360a and the sixth passage 362a, the fifth passage 360b and the sixth passage 362b, An extrusion device for extruding the irradiation object W is provided, and the conveyance direction of the irradiation object W can be changed by 90 degrees.

  Further, as shown in FIG. 7, the transfer device 400 provided in the first elevating passages 370a and 370b includes an elevating device 410a such as an elevator that elevates and lowers the irradiation object W in the vertical direction. In FIG. 7, since the first elevating passage 370a is taken as an example, the elevating device 410a lowers the irradiated object W conveyed by the conveying device 400b provided in the second passage 354a on the second floor vertically downward. Then, it is transferred to the transfer device 400c provided in the first passage 352. The first elevating passage 370b and the second elevating passages 372a and 372b are also provided with an elevating device (not shown), and the elevating device provided in the second elevating passage 372b is similar to the elevating device 410a. The irradiated object W is lowered vertically downward, and the lifting devices provided in the first lifting / lowering path 370b and the second lifting / lowering path 372a raise the irradiated object W vertically upward.

  FIG. 8 is an explanatory diagram for explaining the emission direction of the radiation generated in the irradiation region. As shown in FIG. 8, the radiation generated in the irradiation region R is emitted in all directions of 360 degrees. The radiation generated in the irradiation region R becomes the radiation with the highest dose inside the transport structure 200.

  Therefore, the shielding wall 312 (front wall 312a) that defines the first passage 352 is formed with a thickness in the Z-axis direction that is thick enough to absorb the radiation emitted in the Z-axis direction in FIG. 8A. . The radiation with the highest dose also enters the shielding wall 312 (intermediate wall 312b) that partitions the first passage 352 and the power supply chamber 302, but the power supply chamber 302 is placed between the intermediate wall 312b and the outside E. Since the partitioning shielding wall 312 (rear wall 312c) is provided, the intermediate wall 312b and the rear wall so that the sum of the thicknesses in the Z-axis direction of the intermediate wall 312b and the rear wall 312c is equal to the thickness of the front wall 312a. 312c is formed.

  As shown in FIG. 8B, the floor 310 and the ceiling wall 314 absorb the radiation emitted in the vertical direction (the Y-axis direction in FIG. 8). More specifically, the ground exists vertically below the irradiation region R. Since the ground can absorb radiation, the radiation emitted vertically downward is absorbed by the floor 310 and the ground. Accordingly, the floor 310 can be made thinner than the front wall 312a in consideration of the amount of radiation that the ground can absorb. The ceiling wall 314 is formed to have a thickness that can absorb the radiation emitted vertically upward and block the leakage to the outside E (the same thickness as the front wall 312a).

  Further, as shown in FIG. 8B, the radiation generated in the irradiation region R is emitted in the horizontal direction (X-axis direction in FIG. 8B). Therefore, the right side wall 312d and the left side wall 312e located in the horizontal direction of the irradiation region R are formed to have the same thickness as the front wall 312a.

  In the present embodiment, since the conveyance passage 350 is formed on the first floor and the second floor, the first-floor shielding wall 312 (right side wall 312d) corresponding to the width in the X-axis direction of FIG. And the left side wall 312e) may be formed inside the building 300. In other words, the floor on the second floor can function as the shielding wall 312 on the first floor. Therefore, the radiation emitted in the X-axis direction in FIG. 8B can be reliably blocked and the installation area of the transport structure 200 can be made smaller than before.

  Further, as shown in FIG. 8B, a part of the radiation generated in the irradiation region R and emitted at an angle α (0 <α <90) from the horizontal plane (FIG. 8B ) (Shown by broken arrows) may pass directly from the first passage 352 to the second passages 354a and 354b through the first elevating passages 370a and 370b. Then, the shielding wall 312 (the right side wall 312f and the left side wall 312g) on the second floor needs to have the same thickness as the front wall 312a.

  Therefore, in this embodiment, a part of the ceiling wall 314 that defines the first passage 352 protrudes vertically downward to form the shielding part 330. And the top part 330a of the shielding part 330 (the ceiling wall surface 330a of the first passage 352) is a radiation source (P1, P2) and the end part Q on the irradiation region R side of the bottom surface that defines the second passages 354a, 354b. The shielding part 330 is configured so as to be positioned on the straight lines P1Q and P2Q connecting the two. Here, the generation source P1 is a radiation generation source when the electron beam collides with the irradiation object W, and the generation source P2 is a radiation generation source when the electron beam collides with the floor portion 310.

  Then, the radiation with the highest dose emitted from the generation sources P1 and P2 is always reflected by the shielding unit 330 without directly entering the second floor (second passage 354). Therefore, it is possible to shield the straight incidence of radiation from the generation sources P1 and P2 of the first passage 352 to the second passages 354a and 354b. Thereby, the thickness of the right side wall 312f and the left side wall 312g of the second floor can be made thinner than the front wall 312a.

  Then, as shown in FIGS. 9A and 9B, the radiation whose dose is reduced by the first reflection (T1) at the shielding unit 330 is the floor 310 (FIG. 9A), or Second shielding (T2) is performed by the shielding walls 312 (the right side wall 312d and the left side wall 312e) (FIG. 9B) that divide the first elevating passages 370a and 370b, and the first elevating passages 370a and 370b are divided. The third reflection (T3) is performed on the ceiling wall 314, and the fourth reflection (T4) is performed on the shielding walls 312 (the right side wall 312f and the left side wall 312g) that define the second passages 354a and 354b.

  Thus, the radiation generated in the irradiation region R is reflected four times at the reflection points T1, T2, T3, and T4 before reaching the second passages 354a and 354b. Therefore, even if the energy of the electron beam irradiated from the electron beam irradiation apparatus 100 is, for example, about 10 MeV, it is reflected four times before reaching the second passages 354a and 354b from the irradiation region R. It becomes possible to reduce the dose so that there is no problem even if it is released into E.

  As described above, according to the transport structure 200 according to the present embodiment, the installation area of the building 300 can be reduced, and the radiation E generated based on the electron beam irradiated by the electron beam irradiation apparatus 100 is directed to the outside E. It is possible to reliably block the leakage.

  As mentioned above, although preferred embodiment of this invention was described referring an accompanying drawing, it cannot be overemphasized that this invention is not limited to this embodiment. It will be apparent to those skilled in the art that various changes and modifications can be made within the scope of the claims, and these are naturally within the technical scope of the present invention. Is done.

  For example, in the above-described embodiment, the first passage is the first passage 352, the second passage is the second passages 354a and 354b, and the third passage is the third passages 356a and 356b. The passage may be the third passages 356a and 356b, and the second passage may be the fourth passages 358a and 358b.

  In the above-described embodiment, the first passage (first passage 352) is located vertically below the second passage (second passages 354a and 354b), but the shielding portion 330 extends from the first passage 352. The first passage may be positioned vertically higher than the second passage as long as it can block the rectilinear incidence of radiation into the two passages 354a and 354b.

  Furthermore, in the above-described embodiment, the shielding unit 330 projects a part of the ceiling wall 314 that defines the first passage 352 vertically downward, but the radiation travels straight from the first passage to the second passage. What is necessary is just to be able to shield incidence. For example, as shown in FIG. 10, the shielding part 330 may be provided on the wall surface that divides the first elevating passages 370a and 370b.

  INDUSTRIAL APPLICABILITY The present invention can be used for an object transport structure using an electron beam irradiation apparatus that irradiates an object with an electron beam.

R ... Irradiation area W ... Irradiated object 100 ... Electron beam irradiation apparatus 200 ... Conveying structure 312 ... Shielding wall 314 ... Ceiling wall 330 ... Shielding part 350 ... Conveying passage 352 ... First passage (first passage)
354 ... Second passage (second passage)
356 ... 3rd passage (3rd passage)
370 ... 1st raising / lowering passage 376a ... Carry-in part 376b ... Carry-out part 400 ... Conveyance apparatus

Claims (7)

An electron beam irradiation apparatus for irradiating an object with an electron beam;
An irradiation area provided on a conveyance path defined by a wall surface, wherein the irradiation object is irradiated with an electron beam by the electron beam irradiation device, and radiation is generated based on the electron beam When,
A transport device installed in the transport path and carrying the irradiated object from the carry-in section to the irradiation area and carrying the irradiated object from the irradiation area to the carry-out section;
A first passage constituting a part of the transport passage;
A second passage having a vertical height different from that of the first passage and a distance from the irradiation region being a distance farther than the first passage;
An elevating passage connecting the first passage and the second passage;
A shielding portion that is provided on at least one of a wall surface that defines the first passage and a wall surface that defines the lifting passage, and that shields the radiation from entering the second passage straight from the first passage; ,
A structure for transporting an object to be irradiated.   The said irradiation area | region is provided in a said 1st channel | path, The conveyance structure of the to-be-irradiated object of Claim 1 characterized by the above-mentioned.   The transport structure for an irradiated object according to claim 2, wherein the first passage is positioned vertically below the second passage.   The said electron beam irradiation apparatus irradiates the said electron beam to a perpendicular downward direction, The conveyance structure of the to-be-irradiated object of Claim 3 characterized by the above-mentioned. The shielding portion is a ceiling wall surface defining the first passage;
The ceiling wall surface of the first passage is located on a straight line connecting the radiation generation source in the irradiation region and the end of the bottom surface defining the second passage on the irradiation region side, The transport structure of the irradiated object according to claim 3 or 4.   One end side of the first passage is connected to the second passage through the lifting passage, and the other end side of the first passage is connected to the first passage through another lifting passage. The transport structure for an irradiated object according to any one of claims 3 to 5, wherein the transport structure is connected to a path different from the second path. The conveyance path is
The height of the said 2nd channel | path is equal to the said 2nd channel | path, and it is comprised including the 3rd channel | path orthogonal to the said 2nd channel | path and a horizontal direction. The transport structure of the irradiated object described in 1.