Accelerator and proton therapy apparatus

Abstract

To provide an accelerator and a proton beam treatment device capable of reducing an occupied area space of related components of a conductor and a water pipe of the accelerator.SOLUTION: An accelerator 1 includes a yoke 4, a conductor 21 connected to the yoke 4, and a water pipe 29 connected to the yoke 4, and the conductor 21 and the water pipe 29 are housed together in a cable carrier 25 arranged outside the yoke 4.SELECTED DRAWING: Figure 4

Description

[Technical Field]

[0001] The present invention relates to an accelerator and a proton beam therapy device. [Background technology]

[0002] A conventional technique in this field is a charged particle beam therapy device described in Patent Document 1 below. This charged particle beam therapy device is a device that performs radiation therapy by irradiating a tumor or the like of a patient with a charged particle beam. The charged particle beam therapy device is equipped with an accelerator that accelerates charged particles and emits the charged particle beam. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2016-207688 Summary of the Invention [Problem to be solved by the invention]

[0004] In this type of accelerator, the conductors and water piping may be arranged outside the yoke. It is desirable to reduce the space occupied by such wiring and piping and related components from the viewpoint of reducing the installation space of the accelerator and the charged particle beam therapy system. The present invention aims to provide an accelerator and a proton beam therapy system that realizes a reduction in the area and space occupied by the conductors and water piping related components of the accelerator. [Means for solving the problem]

[0005] The gist of the present invention lies in the following [1] to [8].

[0006] [1] An accelerator comprising a yoke, a conductor connected to the yoke, and a water pipe connected to the yoke, the conductor and the water pipe being housed together in a cable carrier.

[0007] [2] The accelerator described in [1], wherein the conductor includes a first conductor and a second conductor, and the cable carrier houses the water piping between the first conductor and the second conductor.

[0008] [3] The accelerator according to [2], wherein the first conductor is a conductor that can be a source of noise, and the second conductor is a conductor that should be prevented from being affected by the noise.

[0009] [4] The accelerator according to [2] or [3], wherein the first conducting wire is a power line for transmitting electric power, and the second conducting wire is a measurement line for transmitting an electrical signal for measurement.

[0010] [5] The accelerator described in any one of [2] to [4], wherein the first conductor is a conductor having a rated current value equal to or greater than a predetermined threshold, and the second conductor is a conductor having a rated current value less than the threshold.

[0011] [6] An accelerator according to any one of [1] to [5], wherein the yoke comprises a first yoke portion and a second yoke portion that are separable and relatively movable, and the conducting wire and the water piping connect the first yoke portion and the second yoke portion.

[0012] [7] The accelerator according to any one of [1] to [6], wherein the conductor wires include a power line for transmitting electric power and a measurement line for transmitting an electric signal for measurement.

[0013] [8] The accelerator according to any one of [1] to [7], which is a cyclotron.

[0014] [9] A proton beam therapy device comprising the accelerator according to any one of [1] to [8]. [Effects of the Invention]

[0015] SUMMARY OF THE INVENTION An object of the present invention is to provide an accelerator and a proton beam therapy system that realizes a reduction in the area and space occupied by the accelerator's lead wires and related components such as water piping. [Brief explanation of the drawings]

[0016] [Figure 1] FIG. 1 is a diagram showing a proton beam therapy apparatus according to a first embodiment. [Figure 2] FIG. 1 is a perspective view of an accelerator. [Figure 3] FIG. 2 is a side view showing a simplified appearance of the accelerator. [Figure 4] 4 is a cross-sectional view of the cable carrier taken along line IV-IV in FIG. 3. [Figure 5] FIG. 10(a) is a cross-sectional view of a cable carrier of an accelerator according to a second embodiment, and FIG. 10(b) is a cross-sectional view of a cable carrier according to a modified example. DETAILED DESCRIPTION OF THE INVENTION

[0017] [First embodiment] A first embodiment of an accelerator and a proton beam therapy system according to the present invention will be described in detail below with reference to the drawings. As shown in FIG. 1, an accelerator 1 according to this embodiment is incorporated into a proton beam therapy system 51, which is a type of charged particle beam therapy system. For example, the accelerator 1 in this embodiment is a superconducting cyclotron. The proton beam therapy system 51 is a system that irradiates a lesion (e.g., a tumor) inside a patient P with a proton beam to provide therapy. The proton beam therapy system 51 includes the accelerator 1 described above, which accelerates protons (hydrogen ions) and emits the proton beam, an irradiation unit 52 that irradiates the patient P with the proton beam, a rotating gantry 53 that rotates the irradiation unit 52 about a rotation axis A around a treatment table 57 on which the patient P is placed, and a transport line 54 that connects the accelerator 1 and the irradiation unit 52 and transports the proton beam emitted from the accelerator 1 to the irradiation unit 52.

[0018] The above-mentioned accelerator 1 will now be described. FIG. 2 is a perspective view showing the accelerator 1 with the yoke 4 open so that the components housed inside the yoke 4 can be seen. The accelerator 1 generates a proton beam by accelerating protons (hydrogen ions) supplied from an ion source (not shown) inside a vacuum vessel 3 to generate and emit the proton beam. The vacuum vessel 3 is made of, for example, stainless steel. A vacuum pump (not shown) is connected to the vacuum vessel 3. The vacuum vessel 3 creates a vacuum environment inside in which the ions are accelerated.

[0019] The accelerator 1 includes a yoke 4 that can be opened and closed in the vertical direction, and an excitation coil 5 that forms a magnetic field within the vacuum vessel 3. The accelerator 1 also includes a cavity 6 that generates a high-frequency electric field to impart energy to the proton beam, and an RF tuner 11 that adjusts the resonant frequency of the cavity 6. The magnetic field formed within the vacuum vessel 3 by the yoke 4 and excitation coil 5, and the high-frequency electric field formed by the cavity 6, cause the proton beam to orbit in a spiral trajectory, and the traveling speed of the proton beam increases as the radius of the orbit increases.

[0020] The accelerator 1 is also equipped with a deflector 7 that is installed on the inner side of the sidewall of the vacuum vessel 3 and that extracts the accelerated proton beam, a gradient collector 8 that corrects the magnetic field gradient, a collimator 9 that emits the proton beam in a predetermined direction (horizontal direction), and a permanent quadropole magnet 10 that adjusts the focus of the extracted proton beam. The proton beam accelerated within the vacuum vessel 3 is extracted by the deflector 7, the magnetic field gradient is corrected by the gradient collector 8, and the extraction direction is adjusted by the collimator 9. The beam focus of the extracted proton beam is adjusted by the permanent quadropole magnet 10.

[0021] FIG. 3 is a side view showing a simplified external appearance of the accelerator 1. The yoke 4 of the accelerator 1 is circular in plan view and includes a pair of upper and lower yokes: an upper yoke 4a (first yoke portion) and a lower yoke 4b (second yoke portion). The yoke 4 can be opened by vertically raising the upper yoke 4a relative to the lower yoke 4b, allowing for maintenance and the like inside the accelerator 1. The accelerator 1 is provided with a support pillar 12 that guides the up and down movement of the upper yoke 4a and supports the upper yoke 4a. Note that the support pillar 12 is not shown in FIG. 2.

[0022] The accelerator 1 includes a number of conductors 21 connecting the upper yoke 4a and the lower yoke 4b. The conductors 21 include a power line (power line) 22a for transmitting electric power and a measurement line 22b for transmitting electrical signals for measurement. The power line 22a and the measurement line 22b are primarily illustrated in FIG. 5(a). These conductors 21 may be in the form of an "electrical line" consisting of a single conductor, or may be in the form of a "cable" consisting of multiple conductors bundled in a single sheath. Among the conductors 21, the power line 22a is an electric wire or cable having a rated current value equal to or greater than a predetermined threshold, and the measurement line 22b is an electric wire or cable having a rated current value less than the threshold. This threshold may be appropriately determined by the designer of the accelerator 1, e.g., 500 mA or 1 A. The conductors 21 pass outside the yoke 4 and are housed in a cable carrier 25, which will be described later. Both ends of the conductor 21 are connected to conductor ports 27, 27 provided on the outer surfaces of the upper yoke 4a and the lower yoke 4b, respectively.

[0023] The power lines 22a are basically cables connected to a power source. For example, motor cables, coil cables, chopper cables, and ion source cables belong to the power lines 22a. The above motors are used in drive mechanisms such as probes. The coils related to the above coil cables are used in main coils and harmonic coils. The measurement lines 22b are cables connected to measuring instruments and communication devices. For example, analog cables for current detection, analog cables for voltage detection, digital signal cables, and optical cables belong to the measurement lines 22b.

[0024] Conductor 21 includes conductor 23a (hereinafter referred to as "noise source conductor 23a") that can be a noise source due to the current flowing through conductor 21, and conductor 23b (hereinafter referred to as "noise-averse conductor 23b") that is a noise-averse conductor, i.e., a conductor that should be prevented from being affected by noise. Note that noise source conductor 23a and noise-averse conductor 23b are mainly illustrated in FIG. 4.

[0025] Since the power line 22a carries a current, the power line 22a is generally classified as a noise source conductor 23a. As an exception, power lines 22a that have a small effect on the noise-inhibiting conductor 23b are not classified as noise source conductor 23a. For example, power lines 22a with a small applied voltage or power lines 22a carrying a current are not classified as noise source conductor 23a. Furthermore, power lines 22a that have noise countermeasures such as shielding (e.g., a shield for radiated noise countermeasures) are not classified as noise source conductor 23a.

[0026] If the measurement line 22b is exposed to noise, an appropriate measurement signal will not be transmitted, making accurate measurement difficult. Therefore, the measurement line 22b is generally classified as a noise-insensitive conductor 23b. As an exception, measurement lines 22b that are not easily affected by noise are not classified as noise-insensitive conductors 23b. For example, digital signal cables and optical cables are not classified as noise-insensitive conductors 23b because they are relatively less affected by noise. Also, measurement lines 22b that have noise countermeasures such as shielding (shielding to prevent radiated noise, twisted wires, etc.) are not classified as noise-insensitive conductors 23b.

[0027] Among the conductors 21, electric wires or cables whose rated current value is equal to or greater than a predetermined threshold may be classified as noise source conductors 23a, and electric wires or cables whose rated current value is less than the threshold may be classified as anti-noise conductors 23b. The threshold may be appropriately determined by the designer of the accelerator 1, and may be, for example, 500 mA or 1 A.

[0028] The accelerator 1 also includes a number of water pipes 29 connecting the upper yoke 4a and the lower yoke 4b. The water pipes 29 are primarily pipes for circulating cooling water that cools the various components of the accelerator 1. Both ends of the water pipes 29 are connected to water pipe ports 28, 28 on the upper yoke 4a and the lower yoke 4b, respectively. The water pipe ports 28, 28 are provided near the conductor ports 27, 27 on the outer surfaces of the upper yoke 4a and the lower yoke 4b, respectively. The water pipes 29 include, for example, coil pipes through which cooling water for the coils passes and cavity pipes through which cooling water for the cavities passes. The water pipes 29 pass outside the yoke 4 and are housed together with the conductors 21 in a cable carrier 25, which will be described later.

[0029] The conductors 21 and water pipes 29 are provided with a length that allows them to slacken on the sides of the yoke 4 so that they can follow the up and down movement of the upper yoke 4a. The conductors 21 and water pipes 29 are housed together in a single cable carrier 25 located on the outside of the yoke 4. A cable carrier is a mechanical component that reliably supports and guides cables and tubes for power signals and the like that move in conjunction with the moving parts of a device, protecting them from wear and tear. A cable carrier is also sometimes called a "Cableveyor (registered trademark)" or a "cable drag chain." Note that the conductors 21, water pipes 29, and cable carrier 25 are not shown in Figure 2.

[0030] The cable carrier 25 is configured by connecting a large number of cable carrier components (not shown) in a chain shape in the extension direction of the conductors 21 and the water piping 29. Adjacent cable carrier components are connected to each other so as to be rotatable around a rotation axis extending in the width direction of the cable carrier 25. This structure enables the cable carrier 25 to bend in a plane perpendicular to the width direction, and as shown by the two-dot chain line in Figure 3, it can bend together with the conductors 21 and the water piping 29 as the upper yoke 4a moves up and down.

[0031] Figure 4 is a cross-sectional view of cable carrier 25 taken along cross section IV-IV in Figure 3. A cable carrier component of cable carrier 25 has a shell portion 31 made of, for example, a resin material and having a rectangular cylindrical shape, and the hollow portion of shell portion 31 defines storage space 33 for storing conductors 21 and water piping 29. Here, the cross section of storage space 33 is divided into three in the width direction of cable carrier 25, and three regions are considered, which are arranged in order as regions 41, 42, and 43.

[0032] In the accelerator 1 of this embodiment, a large number of water pipes 29 are housed in region 42, which is the center of the three regions. Conductors 21 are housed in regions 41 and 43, sandwiching the water pipe 29 in region 42. More specifically, a large number of noise-source conductors 23a (first conductors) among the conductors 21 are housed in region 41, and a large number of anti-noise conductors 23b (second conductors) among the conductors 21 are housed in region 43. Conductors 21 that are not classified as either noise-source conductors 23a or anti-noise conductors 23b may be housed in either region 41 or 43. In order to clearly define the storage positions of the conductors 21 and the water pipes 29, a large number of partitions 32 that partition the cross section of the storage space 33 are formed integrally with the shell portion 31 within the storage space 33. The presence of the partitions 32 also prevents the conductors 21 and the water pipes 29 from unintentionally moving to other regions.

[0033] As described above, power line 22a is generally classified as noise source conductor 23a, and therefore power line 22a is included in noise source conductor 23a within region 41. Furthermore, measurement line 22b is generally classified as anti-noise conductor 23b, and therefore measurement line 22b is included in anti-noise conductor 23b within region 43. Therefore, in cable carrier 25 of this embodiment, it can be said that many power lines 22a of conductor 21 are housed in region 41, and many measurement lines 22b of conductor 21 are housed in region 43.

[0034] The following describes the effects of the accelerator 1 and proton beam therapy system 51 of this embodiment as described above. For example, in some conventional accelerators, the conductor wires and the water piping are housed in separate cable carriers, and multiple cable carriers are located around the periphery of the yoke. In contrast to this type of accelerator, in the accelerator 1 of this embodiment, the conductor wires 21 and the water piping 29 are housed together in a cable carrier 25 located outside the yoke 4. By housing the conductor wires 21 and the water piping 29 together in a single cable carrier 25 in this way, it is possible to reduce the space occupied by the components related to the conductor wires 21 and the water piping 29 in the accelerator 1.

[0035] In the proton beam therapy device 51, it is preferable to miniaturize the accelerator 1 from the viewpoint of reducing manufacturing costs and reducing the installation space in the building, and for this reason, it is preferable to employ a miniaturized superconducting cyclotron as the accelerator 1. In such a compact accelerator 1, the outer peripheral wall surface of the yoke 4 is also narrow, making it difficult to ensure installation space outside the yoke 4 for the components related to the conductors 21 and the water piping 29. Therefore, when a compact accelerator 1 is employed in the proton beam therapy device 51, a configuration that realizes a reduction in the space occupied by the components related to the conductors 21 and the water piping 29, as described above, is particularly suitable.

[0036] Furthermore, in the storage space 33 of the cable carrier 25, a water pipe 29 is stored in a position between the noise source conductor 23a and the unpleasant noise conductor 23b. In this way, the unpleasant noise conductor 23b, which should be prevented from being affected by noise, is located away from the noise source conductor 23a, which may be a noise source, thereby reducing the influence of noise on the unpleasant noise conductor 23b. Furthermore, since the water pipe 29 is stored between the noise source conductor 23a and the unpleasant noise conductor 23b, which are arranged apart from each other, the storage space 33 is used effectively. In other words, the noise source conductor 23a and the unpleasant noise conductor 23b can be separated while effectively utilizing the cross-sectional area of ​​the cable carrier 25.

[0037] In this embodiment, it is sufficient that at least some of the conductors 21 classified as noise source conductors 23a are housed in region 41, and at least some of the conductors 21 classified as unpleasant noise conductors 23b are housed in region 43. For example, all of the conductors 21 classified as noise source conductors 23a may be housed in region 41, and all of the conductors 21 classified as unpleasant noise conductors 23b may be housed in region 43.

[0038] Furthermore, for example, when the frequency of the current flowing through the power line 22a classified as the noise source conductor 23a is sufficiently low (including DC) or sufficiently high relative to the measurement signal of the measurement line 22b classified as the noise source conductor 23b, the power line 22a and the measurement line 22b may be stored in the same area 41 or 43.

[0039] Second Embodiment A second embodiment of the accelerator and proton beam therapy device according to the present invention will be described. In this embodiment, the arrangement of the conductors 21 and water pipes 29 in the cable carrier 25 is different from that of the first embodiment. Since the other configurations are the same as those of the first embodiment, redundant explanations will be omitted. Fig. 5(a) is a cross-sectional view of the cable carrier 25 in this embodiment. In this embodiment, a large number of water pipes 29 are housed in a central region 42 of the cable carrier 25. A large number of power lines 22a (first conductors) of the conductors 21 are housed in region 41, and a large number of measurement lines 22b (second conductors) of the conductors 21 are housed in region 43.

[0040] The accelerator 1 and proton beam therapy system of this embodiment can also achieve the same effects as those of the first embodiment. Because a current flows through the power line 22a, it is preferable to treat the power line 22a as a noise source. If the measurement line 22b is exposed to noise, an appropriate measurement signal will not be transmitted, making accurate measurement difficult. Therefore, it is preferable to treat the measurement line 22b as a conductor 21 that should be protected from the influence of noise. In the accelerator 1 of this embodiment, the measurement line 22b, which should be protected from the influence of noise, is located away from the power line 22a, which is a noise source, so the influence of noise on the measurement line 22b can be reduced.

[0041] In this embodiment, it is sufficient that at least some of the power lines 22a are housed in the area 41, and at least some of the measurement lines 22b are housed in the area 43. For example, all of the power lines 22a may be housed in the area 41, and all of the measurement lines 22b may be housed in the area 43.

[0042] The present invention can be implemented in various forms, including the above-described embodiment, with various modifications and improvements based on the knowledge of those skilled in the art. Furthermore, it is also possible to configure modified forms by utilizing the technical matters described in the above-described embodiment. The configurations of the respective embodiments may be used in appropriate combination.

[0043] For example, in the first and second embodiments, the storage space 33 of the cable carrier 25 is divided into three regions 41, 42, and 43, but the storage space 33 may be divided into more regions. For example, as shown in FIG. 5(b), the storage space 33 may be divided into a number of (e.g., nine) regions 61, 62, ..., 69, with the conductors 21 and the water pipes 29 stored alternately in each region. In this case, a condition may be satisfied that the noise source conductor 23a and the anti-noise conductor 23b are not stored together in the same region. Alternatively, a condition may be satisfied that the power line 22a and the measurement line 22b are not stored together in the same region.

[0044] Furthermore, although the accelerator 1 exemplified as the first and second embodiments is a type that accelerates charged particles in a horizontal plane and the yoke 4 is capable of opening and closing in the vertical direction, the present invention is not limited to this. That is, the present invention can also be applied to an accelerator that accelerates charged particles in a vertical plane and the yoke 4 is capable of opening and closing in the horizontal direction. Furthermore, the cable carrier 25 that houses the conductor 21 and the water piping 29 may be disposed inside the yoke 4. [Explanation of symbols]

[0045] 1...accelerator, 4...yoke, 4a...upper yoke, 4b...lower yoke, 21...conductor, 22a...power line, 22b...measurement line, 23a...noise source conductor, 23b...anti-noise conductor, 25...cable carrier, 29...water piping, 51...proton beam therapy device.

Claims

1. York and a conductor connected to the yoke; a water pipe connected to the yoke, The accelerator, wherein the conductor and the water pipe are housed together in a cable carrier.

2. the conductive wires include a first conductive wire and a second conductive wire; The accelerator according to claim 1 , wherein the water pipe is housed between the first conductor and the second conductor in the cable carrier.

3. the first conducting wire is a conducting wire that may be a noise source, The accelerator according to claim 2 , wherein the second conductor is a conductor that is to be prevented from being affected by the noise.

4. the first conducting wire is a power line for transmitting power, The accelerator according to claim 2 , wherein the second conducting wire is a measurement wire for transmitting an electrical signal for measurement.

5. the first conductor has a rated current value equal to or greater than a predetermined threshold; The accelerator according to claim 2 , wherein the second conductor has a rated current value less than the threshold value.

6. The yoke includes a first yoke portion and a second yoke portion that are separable and relatively movable, 2. The accelerator according to claim 1, wherein the conducting wire and the water pipe connect the first yoke part and the second yoke part.

7. The accelerator according to claim 1 , wherein the conducting wires include a power line for transmitting electric power and a measurement line for transmitting an electrical signal for measurement.

8. The accelerator according to any one of claims 1 to 7, which is a cyclotron.

9. A proton beam therapy system comprising the accelerator according to any one of claims 1 to 7.

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