Target substrate loading apparatus and radioisotope manufacturing apparatus

Abstract

A target substrate loading device arranges and holds a plurality of target substrates for loading into a target device along the thickness direction, and automatically delivers the target substrates to the target device, which holds the target substrates so that they are irradiated by a charged particle beam from a particle accelerator.

Description

Technical Field

[0001] This invention relates to a target substrate loading apparatus and a radioactive isotope manufacturing apparatus. Background Technology

[0002] Previously, target devices for manufacturing radioactive isotopes using solid targets were known (for example, see Patent Document 1). In such target devices using solid targets, accelerated particles are introduced from a particle accelerator such as a cyclotron, causing them to undergo a nuclear reaction with the elements constituting the solid target, thereby generating a radioactive isotope within the solid target. Then, the radioactive isotope is obtained by recovering the solid target that has undergone the nuclear reaction from the target device and treating it with a strong acid or strong base liquid to dissolve the solid target.

[0003] Previous technical documents Patent documents Patent Document 1: Japanese Patent Application Publication No. 61-246699 Summary of the Invention

[0004] The technical problem to be solved by the invention However, when loading and unloading the target substrate, which serves as a solid target, into the target device, it is necessary to stop the particle accelerator, confirm that the radiation intensity has decreased to below a specified level, and then allow personnel to enter the shielding enclosure to perform the work. Therefore, each time the target substrate is placed into the target device, the personnel are exposed to radiation. The object of the present invention is to provide a target substrate loading device and a radioactive isotope manufacturing apparatus capable of automatically loading target substrates into the target device.

[0005] means for solving technical problems The main idea of ​​this invention is in the following [1] to [5].

[0006] [1] A target substrate loading device, which arranges and holds a plurality of target substrates for loading into a target device along the thickness direction, and automatically delivers the target substrates to the target device, wherein the target device holds the target substrates and irradiates them with a charged particle beam from a particle accelerator.

[0007] [2] The target substrate loading apparatus according to [1] includes: a magazine section for holding a plurality of target substrates arranged along the thickness direction; and a substrate delivery section for delivering the target substrates held by the magazine section to the target device.

[0008] [3] According to the target substrate loading apparatus of [2], the substrate delivery unit includes: a substrate discharge hole disposed below the target substrate held by the hopper unit for the target substrate to pass through and fall; and a hopper drive unit for driving the hopper unit relative to the substrate discharge hole along the arrangement direction of the target substrate.

[0009] [4] According to the target substrate loading device of [3], the hopper drive unit includes: a ratchet part disposed in the hopper part and having a plurality of ratchet teeth arranged in the same direction as the target substrate; and a claw part engaged with the ratchet part and reciprocating along the arrangement direction of the target substrate.

[0010] [5] A radioactive isotope manufacturing apparatus comprising: a target substrate loading device as described in any one of [1] to [4]; and the target device for receiving and holding the target substrate delivered from the target substrate loading device; and manufacturing a radioactive isotope by irradiating the target substrate held by the target device with a beam of charged particles.

[0011] Invention Effects According to the present invention, a target substrate loading device and a radioactive isotope manufacturing device are provided, which can automatically load target substrates into a target device. Attached Figure Description

[0012] Figure 1 This is a side view schematically illustrating an embodiment of a radioactive isotope manufacturing apparatus.

[0013] Figure 2 This is a top view schematically illustrating an embodiment of a radioactive isotope manufacturing apparatus.

[0014] Figure 3 It is a top view schematically showing the target device in the open state.

[0015] Figure 4 (a) is a cross-sectional view showing the substrate slot near the target device in the open state, (b) is a cross-sectional view showing the substrate slot near the target device in the closed state, and (c) is a cross-sectional view of IVc-IVc in (b).

[0016] Figure 5 (a) is a top view showing the mechanism of the target substrate loading device, and (b) is a side sectional view of it.

[0017] Figure 6 (a) is a top view showing the target substrate loading device in operation, and (b) is a side sectional view of it.

[0018] Figure 7 (a) is the successor Figure 6 The following is a top view of the target substrate loading device in operation, and (b) is its side sectional view.

[0019] Figure 8 (a) is a continuation Figure 7 The following is a top view of the target substrate loading device in operation. Figure 8 (b) is its side sectional view. Detailed Implementation

[0020] The radioactive isotope manufacturing apparatus 100 of this embodiment will be described with reference to the accompanying drawings. Figure 1 This is a schematic side view of a radioactive isotope manufacturing apparatus 100. Figure 2 This is its top view. As shown in the figure, the radioactive isotope manufacturing apparatus 100 includes a target device 101 and a target substrate loading device 103 disposed above the target device 101.

[0021] The target device 101 is a device for holding the target substrate 10. The target substrate 10 is, for example, configured as an elongated plate, and a metal layer formed of target material is formed on its surface. In the manufacturing process of a radioactive isotope, the target substrate 10 is placed in the target device 101, and the target device 101... Figure 1 and Figure 2 The target device 101 is moved to the left. Then, the front end of the target device 101 is inserted into the manifold 201 of the particle accelerator 200, so that the front end face of the target device 101 is pressed tightly against the receiving surface of the manifold 201, thereby installing the target device 101 in the manifold 201 of the particle accelerator 200. The target substrate 10 is held by the target device 101 in an orientation tilted about a vertical axis relative to the irradiation direction of the charged particle beam B. In this state, the particle accelerator 200 irradiates the target substrate 10 within the target device 101 with the charged particle beam B. In the portion of the irradiated charged particle beam B, trace amounts of radioactive isotopes are generated through nuclear reactions in the target material.

[0022] In the radioisotope manufacturing apparatus 100 of this embodiment, the target substrate 10 is a dissolving metal target, which can dissolve the target material at the irradiation location after irradiation by the charged particle beam B. Then, after the dissolution action, liquid is supplied to a purification device (not shown) in the hot cell for subsequent processes. Furthermore, the purification of metal nuclides with this structure can be achieved by adding a single infusion line to an existing facility.

[0023] Figure 3 This is a schematic top view showing the target device 101 in the open state. (Example) Figures 1-3 As shown, the target device 101 is cylindrical. The target device 101 includes a main body 2, a front surface flange 3 disposed in front of the main body 2 (upstream of the charged particle beam B), and an intermediate retainer 4 disposed between the main body 2 and the front surface flange 3. The main body 2, the intermediate retainer 4, and the front surface flange 3 are divided along the irradiation direction of the charged particle beam B. The joints between the main body 2 and the intermediate retainer 4, and between the intermediate retainer 4 and the front surface flange 3, are provided along vertical surfaces that obliquely intersect the irradiation direction of the charged particle beam B.

[0024] The front surface flange 3 can reciprocate relative to the main body 2 along the irradiation direction of the charged particle beam B, and the intermediate holder 4 can also reciprocate relative to the main body 2 along the irradiation direction of the charged particle beam B. In order to enable such reciprocating movement, a drive unit (not shown) is provided on the target device 101, and a guide rod 42 is provided to guide the above movement.

[0025] In the main body 2, a cooling water circulation hole 13 is formed for cooling the target substrate 10. During the irradiation process of the charged particle beam B, the cooling water in the cooling water circulation hole 13 contacts and flows with the back side of the target substrate 10 in the intermediate holder 4, thereby cooling the heated target substrate 10.

[0026] A through hole 32 is formed in the front surface flange 3 to allow the charged particle beam B to pass through. An O-ring (not shown) is provided on the front surface of the front surface flange 3 around the opening of the through hole 32. During the irradiation process of the charged particle beam B, the front surface of the front surface flange 3 is pressed against the manifold 201 of the particle accelerator 200. Figure 1 The receiving surface of the through hole 32 is used to connect the beam exit of the particle accelerator 200.

[0027] The intermediate holder 4 is a component for holding the target substrate 10. The target substrate 10 is held in the substrate slot 47 of the intermediate holder 4 in an inclined position about a vertical axis relative to the irradiation direction of the charged particle beam B. The intermediate holder 4 includes a front plate 43 and a rear plate 44 that clamp the target substrate 10 in the thickness direction and are parallel to each other. The substrate slot 47 for loading the target substrate 10 is formed as the space between the front plate 43 and the rear plate 44. In addition, the intermediate holder 4 does not have a top plate and a bottom plate for the substrate slot 47, so the target substrate 10 cannot be supported in the substrate slot 47 by the intermediate holder 4 alone. The structure for supporting the target substrate 10 in the substrate slot 47 will be described later.

[0028] Figure 4 (a) is a cross-sectional view showing the area near the substrate slot 47 with the target device 101 in the open state. Figure 4 (b) is a cross-sectional view showing the area near the substrate slot 47 when the target device 101 is in the closed state. Figure 4 (c) is a cross-sectional view of IVc-IVc in (b). Figure 4As shown, a hole 43a of a predetermined shape is formed on the front plate 43, through which the target substrate 10 cannot pass. During the irradiation process of the charged particle beam B, the rear surface 3b of the front surface flange 3 is pressed against the surface of the target substrate 10 in the substrate slot 47 through the hole 43a, and the opening end face of the through hole 32 faces the target material on the target substrate 10. Similarly, a hole 44a of a predetermined shape is formed on the rear plate 44, through which the target substrate 10 cannot pass. During the irradiation process of the charged particle beam B, the front surface 2a of the main body 2 is pressed against the back side of the target substrate 10 in the substrate slot 47 through the hole 44a, and the cooling water circulation hole 13 is connected to the back side of the target substrate 10. Thus, in the target device 101, the target substrate 10 is clamped between the front surface flange 3 and the main body 2.

[0029] Furthermore, a boss 20 is formed below the cooling water circulation hole 13 on the front surface 2a of the main body 2. The boss 20 protrudes outward toward the intermediate retainer 4 by an amount equal to the thickness of the substrate slot 47. When the main body 2 is engaged with the intermediate retainer 4, the boss 20 is inserted into the lower end of the substrate slot 47 through the hole 44a, thereby forming the bottom wall of the substrate slot 47. Then, the target substrate 10, which is inserted into the substrate slot 47 from above, is supported by the boss 20 located at the lower end of the substrate slot 47 and remains in the substrate slot 47. Furthermore, by separating the main body 2 and the intermediate retainer 4 in the irradiation direction of the charged particle beam B, the boss 20 is removed from the substrate slot 47, causing the unsupported target substrate 10 to fall downward from the substrate slot 47.

[0030] Next, the target substrate loading apparatus 103 will be described. Hereinafter, as... Figure 2 The reference axis A is shown to illustrate the positional relationship of each part. In a top view, the reference axis A extends in a direction orthogonal to the target substrate 10 held by the target device 101. Figure 5 (a) is a top view showing the mechanism of the target substrate loading device 103. Figure 5 (b) is its side sectional view. The target substrate loading device 103 is a device for storing multiple new target substrates 10 and automatically loading the target substrates 10 one by one into the substrate slots 47 of the target device 101.

[0031] The target substrate loading device 103 includes: a housing 51; a hopper 53 disposed inside the housing 51 and forming a frame for holding a plurality of target substrates 10; and a substrate delivery 55 that automatically delivers the target substrates 10 held by the hopper 53 one by one to the target device 101.

[0032] A groove 53a is formed within the frame of the hopper section 53, capable of receiving target substrates 10 one by one. The groove 53a can receive the target substrates 10 in a vertically upright position (with the surface and back side forming a vertical plane), and the target substrates 10 within the groove 53a are orthogonal to the reference axis A. That is, the target substrates 10 are received within the groove 53a with the reference axis A as the thickness direction. The target substrates 10 are not firmly held within the groove 53a; the groove 53a restricts horizontal displacement but does not restrict vertical movement. The lower end of the target substrates 10 received within the groove 53a contacts the bottom surface of the housing 51, and the target substrates 10 are supported by the bottom plate of the housing 51 and remain within the groove 53a. Without the bottom plate of the housing 51, the target substrates 10 would detach from the groove 53a and slide downwards.

[0033] As described above, multiple grooves 53a are arranged along the reference axis A with a pitch of, for example, about 2 to 3 times the thickness of the target substrate 10. Therefore, in the hopper section 53, the multiple target substrates 10 are maintained in a state in which they are arranged along the thickness direction with a pitch of, for example, about 2 to 3 times the thickness.

[0034] The hopper section 53 is configured to move parallel to the reference axis A within the housing 51. Specifically, a guide shaft 52 extending along the reference axis A is provided within the housing 51, and the side of the hopper section 53 is slidably engaged with the guide shaft 52. The hopper section 53 is guided by the guide shaft 52 and moves parallel to the reference axis A within the housing 51.

[0035] The substrate delivery unit 55 includes a hopper drive unit 57 and a substrate discharge hole 59. The hopper drive unit 57 drives the hopper unit 53 relative to the substrate discharge hole 59 along the reference axis A. Specifically, the hopper drive unit 57 drives the hopper unit 53 within the housing 51 along the reference axis A. The hopper drive unit 57 includes: a ratchet portion 61 provided on the side of the hopper unit 53 opposite to the guide shaft 52 side; a pawl portion 63 engaging with the ratchet portion 61; and a drive device 67 that reciprocates the pawl portion 63. The ratchet portion 61 has a plurality of ratchet teeth 61a arranged linearly along the reference axis A at the same pitch as the groove 53a. The ratchet teeth 61a are teeth that are inclined only on one side, and the pawl portion 63 is a ratchet pawl that engages only on the other side of the ratchet teeth 61a. The ratchet portion 61 and the pawl portion 63 constitute a ratchet mechanism that causes the hopper unit 53 to move only in one direction. In addition, in Figure 5 In this example, the ratchet mechanism is only provided on one side of the hopper section 53, but it is also possible to provide one on each of the two side sides of the hopper section 53.

[0036] A drive unit 67 is fixed to the outer side of the housing 51; for example, a cylinder is used as the drive unit 67. The drive unit 67 reciprocates the piston 67a along the reference axis A. The aforementioned claw 63 is fixed to the piston 67a of the drive unit 67 via a predetermined connecting part 67b, and the drive unit 67 can cause the claw 63 to reciprocate along the reference axis A. The drive unit 67 causes the claw 63 to reciprocate with a stroke equal to one pitch of the ratchet teeth 61a, thereby pulling one ratchet tooth 61a by the claw 63, which allows the hopper section 53 to move to the left in the reference axis A direction. At this time, the amount of movement of the hopper section 53 is the same as one pitch of the target substrate 10 arrangement. That is, in Figure 5 In the example, whenever the claw 63 reciprocates once with a stroke of one pitch of the ratchet tooth 61a, the bin 53 moves to the left by one pitch.

[0037] A spring (not shown) is provided on the guide shaft 52, and the spring applies a force to the hopper section 53 in the opposite direction to the movement direction of the hopper section 53. When the hopper section 53 stops, the force applied by the spring causes the ratchet tooth 61a to press tightly against the pawl section 63, thereby positioning the hopper section 53.

[0038] The substrate discharge hole 59 is a hole provided on the bottom plate of the housing 51 and extending vertically through the bottom plate. The substrate discharge hole 59 is an elongated hole extending in a direction orthogonal to the reference axis A, and has a size and shape that allows the target substrate 10 in a vertical position to pass through with a small gap. Such a substrate discharge hole 59 is provided at one point within the movable range of the hopper section 53.

[0039] The operation of the target substrate loading device 103 described above will be explained. When the target substrate loading device 103 is in operation, the substrate slot 47 of the target device 101 is located vertically below the substrate discharge hole 59, and the target substrate loading device 103 is configured such that the substrate discharge hole 59 overlaps with the substrate slot 47 when viewed from above. Furthermore, in the target device 101, the intermediate retainer 4 is engaged with the main body 2, and the boss 20 is inserted into the lower end of the substrate slot 47.

[0040] During operation, the target substrate loading device 103 operates as follows: (e.g.) Figure 5 As shown in (a) and (b), at the start of operation, a target substrate 10 is pre-prepared and placed in each slot 53a of the material storage section 53. From this state onwards, as... Figure 6 (a) and (b) and Figure 7 As shown in (a) and (b), when the drive device 67 is driven to reciprocate the claw 63 once, the hopper 53 moves one pitch of the ratchet tooth 61a along the reference axis A. As a result, the target substrate 10 at the foremost position reaches the position of the substrate discharge hole 59. Thus, as... Figure 7As shown in (a) and (b), the target substrate 10 falls into the substrate discharge hole 59 and detaches from the hopper section 53, falling freely downwards through the substrate discharge hole 59. Alternatively, as shown, the substrate discharge hole 59 may also be conical to allow the target substrate 10 to fall smoothly into and pass through the substrate discharge hole 59.

[0041] The falling target substrate 10 is embedded into the vertically downward substrate slot 47, thus being filled into the substrate slot 47. The target device 101, after being filled with the target substrate 10, is installed in the manifold 201 of the particle accelerator 200 as described above. Figure 1 This process irradiates the target substrate 10 with a charged particle beam B. After irradiation with the charged particle beam B, and following a prescribed treatment, the intermediate holder 4 separates from the main body 2, the boss 20 exits from the substrate slot 47, and the target substrate 10 slides out of the substrate slot 47 and is discharged.

[0042] In the next operation, the drive unit 67 is driven again, and the hopper section 53 moves the ratchet teeth 61a by one pitch along the reference axis A. As a result, the second target substrate 10, starting from the foremost position, falls through the substrate discharge hole 59 and is inserted into the substrate slot 47 of the target device 101. By repeating the above actions, the target substrate loading device 103 can load the target device 101 with target substrates 10 one by one. Finally, as... Figure 8 As shown in (a) and (b), after the number of target substrates 10 prepared in advance has been used up, for example, the operator can manually replenish the target substrates 10 to the hopper section 53.

[0043] The effects of the target substrate loading device 103 and the radioactive isotope manufacturing device 100 equipped with the target substrate loading device 103 described above will be explained.

[0044] According to the target substrate loading device 103, the drive device 67 can automatically load the target substrates 10 prepared in advance in the hopper section 53 into the target device 101 one by one. Therefore, there is no need for manual operation of loading the target substrates 10 into the target device 101, thus avoiding radiation exposure for operators. Furthermore, there is no need for skills such as disassembling or assembling the target device 101 when loading the target substrates 10.

[0045] Furthermore, in the target substrate loading apparatus 103, the target substrates 10 are arranged along the thickness direction and held by the hopper section 53. Therefore, multiple target substrates 10 can be prepared in the target substrate loading apparatus 103 without increasing the volume. Thus, the size of the hopper section 53 can be kept small, and the target substrate loading apparatus 103 can be miniaturized, thereby achieving miniaturization of the radioisotope manufacturing apparatus 100.

[0046] Furthermore, the target substrate 10 is fed out by moving the hopper section 53 by one pitch at a time through a ratchet mechanism. Therefore, the automatic loading of the target substrate 10 can be achieved by a simple drive device such as a cylinder that only performs reciprocating movement.

[0047] The present invention, exemplified by the embodiments described above, can be implemented in various ways with modifications and improvements based on the knowledge of those skilled in the art. Furthermore, variations can be constructed using the technical aspects described in the above embodiments. The structures of various embodiments can also be appropriately combined.

[0048] For example, in one embodiment, the target substrate 10 is allowed to fall freely from the target substrate loading device 103 and be loaded into the substrate slot 47. However, a guide may also be provided to guide the gravity-based movement of the target substrate 10 from the substrate discharge hole 59 of the target substrate loading device 103 to the substrate slot 47.

[0049] [Symbol Explanation] 10-Target substrate, 53-Feed bin section, 55-Substrate delivery section, 57-Feed bin drive section, 59-Substrate discharge hole, 61-Ratchet section, 61a-Ratchet tooth, 63-Claw section, 100-Radioactive isotope manufacturing apparatus, 101-Target apparatus, 103-Target substrate loading apparatus, 200-Particle accelerator, B-Charged particle beam.

Claims

1. A target substrate loading apparatus that arranges and holds a plurality of target substrates for loading into a target device along the thickness direction, and automatically delivers the target substrates to the target device, wherein the target device holds the target substrates and irradiates them with a charged particle beam from a particle accelerator.

2. The target substrate loading apparatus according to claim 1, wherein, have: The hopper section holds a plurality of target substrates arranged along the thickness direction; and The substrate delivery unit delivers the target substrate held by the hopper unit to the target device.

3. The target substrate loading apparatus according to claim 2, wherein, The substrate delivery section includes: A substrate discharge hole is provided below the target substrate held by the hopper section, allowing the target substrate to pass through and fall; and The hopper drive unit drives the hopper unit relative to the substrate discharge hole along the arrangement direction of the target substrate.

4. The target substrate loading apparatus according to claim 3, wherein, The hopper drive unit includes: A ratchet portion, disposed in the hopper portion and having a plurality of ratchet teeth arranged in the same direction as the target substrate; and The claw engages with the ratchet portion and reciprocates along the arrangement direction of the target substrate.

5. A radioactive isotope manufacturing apparatus, comprising: The target substrate loading apparatus according to claim 1; and The target device receives and holds the target substrate delivered from the target substrate loading device. Radioactive isotopes are produced by irradiating the target substrate held by the target device with the beam of charged particles.

Images