JP6813410B2 - Charged particle beam therapy device and power supply device - Google Patents

Description

The present invention relates to a charged particle beam therapy device and a power supply device.

Conventionally, as a charged particle beam therapy device that treats an affected part of a patient by irradiating it with a charged particle beam, for example, the device described in Patent Document 1 is known. In the charged particle beam therapy apparatus described in Patent Document 1, the charged particle beam accelerated by the accelerator is scanned by a scanning electromagnet according to a predetermined scanning path, and the irradiated body is irradiated (scanning method).

Japanese Unexamined Patent Publication No. 2004-358237

Here, the charged particle beam therapy apparatus as described above stops the irradiation of the charged particle beam when an error occurs during the irradiation of the charged particle beam. For example, the following method may be adopted as an operation when the irradiation of the charged particle beam is stopped in this way. That is, the charged particle beam therapy device may store the stop position of the charged particle beam in the scanning path at the time of stop, and after the error is resolved, start irradiating the charged particle beam from the stored stop position. is there. In order to restart the irradiation of the charged particle beam from the accurate position as described above, it is necessary to accurately grasp the stop position of the charged particle beam. Here, the stop position of the charged particle beam can be indirectly grasped from the current value of the scanning electromagnet. In the conventional charged particle beam therapy apparatus, there is room for improving the measurement accuracy of the current value of the scanning electromagnet in order to accurately grasp the stop position of the charged particle beam.

Therefore, an object of the present invention is to provide a charged particle beam therapy device and a power supply device capable of improving the measurement accuracy of the current value of the scanning electromagnet.

In order to solve the above problems, the charged particle beam therapy device according to the present invention is a charged particle beam therapy device that irradiates an irradiated object with a charged particle beam, and includes a scanning electromagnet that scans the charged particle beam and a scanning electromagnet. It is provided so as to cover the periphery of the electromagnet power supply that supplies electric power, the first wire that connects the electromagnet power supply and the scanning electromagnet, and the first wire, and one end on the electromagnet power supply side is connected to the first wire. As a result, the second wire, which is parallel to the first wire, is connected to the first wire on the scanning electromagnet side of the connection between the first wire and the second wire, and the current of the first wire is connected. It is provided with a current measuring unit for measuring.

The charged particle beam therapy apparatus according to the present invention includes a first wire connecting the electromagnet power supply and the scanning electromagnet, and a second wire provided so as to cover the periphery of the first wire. By covering the circumference of the first line with the second line, a distributed capacitance is formed between the first line and the second line. Further, a distributed capacitance is formed between the second line on the outer peripheral side and the external structure. Here, since the second line is parallel to the first line, the first line and the second line have the same potential. Therefore, no current flows through the distributed capacitance between the first line and the second line. On the other hand, a current flows through the distributed capacitance between the second line and the external structure. However, the current flows through the second line but not through the first line. Therefore, the current measured by the current measuring unit connected to the first wire on the scanning electromagnet side of the connecting portion between the first wire and the second wire is between the second wire and the external structure. It is possible to prevent the current flowing to the distributed capacitance of. As a result, the measurement accuracy of the current value of the scanning electromagnet can be improved.

The charged particle beam therapy apparatus according to the present invention is provided between the first wire and the second wire on the scanning electromagnet side of the connection portion, and insulates the first wire and the second wire. The insulating material and the second insulating material provided so as to cover the periphery of the second wire may be further provided, and the second insulating material may be connected to the installation potential member which is the installation potential. As a result, the first wire and the entire second wire can be suitably insulated while improving the measurement accuracy of the current value of the scanning electromagnet.

The power supply device according to the present invention is a power supply device that supplies power to a scanning electromagnet that scans a charged particle beam irradiated to an irradiated body, and is an electromagnet power supply that supplies power to the scanning electromagnet, and an electromagnet power supply and a scanning electromagnet. A first wire for connecting to and a first wire, which is provided so as to cover the periphery of the first wire, and is parallel to the first wire by connecting one end on the electromagnet power supply side to the first wire. The second wire and a current measuring unit which is connected to the first wire on the scanning electromagnet side of the connecting portion between the first wire and the second wire and measures the current of the first wire are provided.

According to this power supply device, the same actions and effects as those of the above-mentioned charged particle beam therapy device can be obtained.

The power supply device according to the present invention is provided between the first wire and the second wire on the scanning electromagnet side of the connection portion, and is a first insulating material that insulates the first wire and the second wire. And a second insulating material provided so as to cover the periphery of the second wire, and the second insulating material may be connected to the installation potential member which is the installation potential. As a result, the first wire and the entire second wire can be suitably insulated while improving the measurement accuracy of the current value of the scanning electromagnet.

According to the present invention, the measurement accuracy of the current value of the scanning electromagnet can be improved.

It is a schematic block diagram of the charged particle beam therapy apparatus which concerns on one Embodiment of this invention. It is a schematic block diagram near the irradiation part of the charged particle beam therapy apparatus of FIG. It is a figure which shows the layer set for a tumor. It is a schematic diagram which shows the structure around the connection part of the electromagnet power source of the power source device which concerns on this embodiment, and a cable. It is a cross section of the cable of the power supply device which concerns on this embodiment. It is a circuit diagram of the power supply device which concerns on this embodiment. It is a circuit diagram of the power supply device which concerns on a comparative example.

Hereinafter, the charged particle beam therapy apparatus according to the embodiment of the present invention will be described with reference to the accompanying drawings. In the description of the drawings, the same elements are designated by the same reference numerals, and duplicate description will be omitted.

As shown in FIG. 1, the charged particle beam therapy apparatus 1 according to the embodiment of the present invention is an apparatus used for cancer treatment by radiation therapy and the like, and charged particles generated by an ion source (not shown). An accelerator 3 that accelerates and emits as a charged particle beam, an irradiation unit 2 that irradiates the irradiated body with the charged particle beam, and a beam transport line 41 that transports the charged particle beam emitted from the accelerator 3 to the irradiation unit 2. , Is equipped. The irradiation unit 2 is attached to a rotating gantry 5 provided so as to surround the treatment table 4. The irradiation unit 2 is made rotatable around the treatment table 4 by the rotating gantry 5.

FIG. 2 is a schematic configuration diagram of the vicinity of the irradiation portion of the charged particle beam therapy apparatus of FIG. In the following description, the terms "X direction", "Y direction", and "Z direction" will be used. The "Z direction" is a direction in which the base axis AX of the charged particle beam B extends, and is a depth direction of irradiation of the charged particle beam B. The "base axis AX" is the irradiation axis of the charged particle beam B when it is not deflected by the scanning electromagnet 6 described later. FIG. 2 shows how the charged particle beam B is irradiated along the base axis AX. The "X direction" is one direction in a plane orthogonal to the Z direction. The "Y direction" is a direction orthogonal to the X direction in a plane orthogonal to the Z direction.

First, with reference to FIG. 2, a schematic configuration of the charged particle beam therapy apparatus 1 according to the present embodiment will be described. The charged particle beam therapy device 1 is an irradiation device according to a scanning method. The scanning method is not particularly limited, and line scanning, raster scanning, spot scanning, or the like may be adopted. As shown in FIG. 2, the charged particle beam therapy device 1 includes an accelerator 3, an irradiation unit 2, a beam transport line 41, and a control unit 7.

The accelerator 3 is a device that accelerates a charged particle and emits a charged particle beam B having a preset energy. Examples of the accelerator 3 include a cyclotron, a synchrotron, a synchrotron, a linac, and the like. When a cyclotron that emits a charged particle beam B having a predetermined energy is adopted as the accelerator 3, the energy of the charged particle beam B sent to the irradiation unit 2 is adjusted (decreased) by adopting the energy adjusting unit 20. It becomes possible to make it. Since the synchrotron can easily change the energy of the emitted charged particle beam B, the energy adjusting unit 20 may be omitted when the synchrotron is adopted as the accelerator 3. The accelerator 3 is connected to the control unit 7, and the supplied current is controlled. The charged particle beam B generated by the accelerator 3 is transported to the irradiation nozzle 9 by the beam transport line 41. The beam transport line 41 connects the accelerator 3, the energy adjusting unit 20, and the irradiation unit 2, and transports the charged particle beam B emitted from the accelerator 3 to the irradiation unit 2.

The charged particle beam therapy device 1 is further provided with a beam chopper 16 which is arranged in the accelerator 3 and blocks the charged particle beam B emitted from the ion source. In the operating state (ON) of the beam chopper 16, the charged particle beam B emitted from the ion source is blocked and is not emitted from the accelerator 3. In the stopped state (OFF) of the beam chopper 16, the charged particle beam B emitted from the ion source is emitted from the accelerator 3 without being cut off. The operating state and the stopped state of the beam chopper 16 can be switched by a beam chopper switch (not shown). A device other than the beam chopper may be used as a means for switching between irradiation and non-irradiation of charged particle beams. For example, a shutter may be provided in the beam transport line to block the charged particle beam with the shutter. Alternatively, the charged particle beam may be emitted from the accelerator 3 only when the charged particle beam is irradiated using the deflector (electrode) provided in the accelerator 3.

The irradiation unit 2 irradiates the tumor (irradiated body) 14 in the body of the patient 15 with the charged particle beam B. The charged particle beam B is a high-speed acceleration of a charged particle, and examples thereof include a proton beam, a heavy particle (heavy ion) beam, and an electron beam. Specifically, the irradiation unit 2 is a device that irradiates the tumor 14 with a charged particle beam B emitted from an accelerator 3 that accelerates charged particles generated by an ion source (not shown) and transported by a beam transport line 41. .. The irradiation unit 2 includes a scanning electromagnet 6, a quadrupole electromagnet 8, a profile monitor 11, a dose monitor 12, flatness monitors 13a and 13b, and a degrader 30. The scanning electromagnet 6, the monitors 11, 12, 13a, 13b, the quadrupole electromagnet 8, and the degrader 30 are housed in the irradiation nozzle 9. The quadrupole electromagnet 8, the profile monitor 11, the dose monitor 12, the flatness monitors 13a and 13b, and the degrader 30 may be omitted.

The scanning electromagnet 6 includes an X-direction scanning electromagnet 6a and a Y-direction scanning electromagnet 6b. The X-direction scanning electromagnet 6a and the Y-direction scanning electromagnet 6b are each composed of a pair of electromagnets, and the magnetic field between the pair of electromagnets is changed according to the current supplied from the control unit 7, and charged particles passing between the electromagnets. Scan line B. The X-direction scanning electromagnet 6a scans the charged particle beam B in the X direction, and the Y-direction scanning electromagnet 6b scans the charged particle beam B in the Y direction. These scanning electromagnets 6 are arranged on the base axis AX in this order on the downstream side of the charged particle beam B with respect to the accelerator 3.

The quadrupole electromagnet 8 includes an X-direction quadrupole electromagnet 8a and a Y-direction quadrupole electromagnet 8b. The X-direction quadrupole electromagnet 8a and the Y-direction quadrupole electromagnet 8b narrow and converge the charged particle beam B according to the current supplied from the control unit 7. The X-direction quadrupole electromagnet 8a converges the charged particle beam B in the X direction, and the Y-direction quadrupole electromagnet 8b converges the charged particle beam B in the Y direction. The beam size of the charged particle beam B can be changed by changing the current supplied to the quadrupole electromagnet 8 to change the aperture amount (convergence amount). The quadrupole electromagnet 8 is arranged on the base axis AX between the accelerator 3 and the scanning electromagnet 6 in this order. The beam size is the size of the charged particle beam B in the XY plane. The beam shape is the shape of the charged particle beam B in the XY plane.

The profile monitor 11 detects the beam shape and position of the charged particle beam B for alignment at the time of initial setting. The profile monitor 11 is arranged on the base axis AX between the quadrupole electromagnet 8 and the scanning electromagnet 6. The dose monitor 12 detects the intensity of the charged particle beam B. The dose monitor 12 is arranged on the base axis AX and downstream of the scanning electromagnet 6. The flatness monitors 13a and 13b detect and monitor the beam shape and position of the charged particle beam B. The flatness monitors 13a and 13b are arranged on the base axis AX and on the downstream side of the charged particle beam B with respect to the dose monitor 12. Each of the monitors 11, 12, 13a and 13b outputs the detected detection result to the control unit 7.

The degrader 30 reduces the energy of the passing charged particle beam B to fine-tune the energy of the charged particle beam B. In the present embodiment, the degrader 30 is provided at the tip 9a of the irradiation nozzle 9. The tip 9a of the irradiation nozzle 9 is the downstream end of the charged particle beam B.

The control unit 7 is composed of, for example, a CPU, a ROM, a RAM, and the like. The control unit 7 controls the accelerator 3, the scanning electromagnet 6, and the quadrupole electromagnet 8 based on the detection results output from the monitors 11, 12, 13a, and 13b. Further, in the present embodiment, the control unit 7 feeds back the detection results of the monitors 11, 12, 13a, and 13b, and controls the quadrupole electromagnet 8 so that the beam size of the charged particle beam B becomes constant. ..

Further, the control unit 7 of the charged particle beam therapy device 1 is connected to a treatment planning device 100 that performs a treatment plan for the charged particle beam therapy. The treatment planning device 100 measures the tumor 14 of the patient 15 by CT or the like before treatment, and plans the dose distribution (dose distribution of charged particle beams to be irradiated) at each position of the tumor 14. Specifically, the treatment planning device 100 creates a treatment planning map for the tumor 14. The treatment planning device 100 transmits the created treatment planning map to the control unit 7.

When irradiating a charged particle beam by the scanning method, the tumor 14 is virtually divided into a plurality of layers in the Z direction, and the charged particle beam is scanned and irradiated in one layer so as to follow the scanning path defined in the treatment plan. To do. Then, after the irradiation of the charged particle beam in the one layer is completed, the irradiation of the charged particle beam in the adjacent next layer is performed.

When the charged particle beam therapy device 1 shown in FIG. 2 irradiates the charged particle beam B by the scanning method, the quadrupole electromagnet 8 is set to the operating state (ON) so that the passing charged particle beam B converges.

Subsequently, the charged particle beam B is emitted from the accelerator 3. The emitted charged particle beam B is scanned so as to follow the scanning path defined in the treatment plan under the control of the scanning electromagnet 6. As a result, the charged particle beam B is irradiated to the tumor 14 while being scanned within the irradiation range in one layer set in the Z direction. When the irradiation of one layer is completed, the charged particle beam B is irradiated to the next layer.

The charged particle beam irradiation image of the scanning electromagnet 6 under the control of the control unit 7 will be described with reference to FIGS. 3A and 3B. FIG. 3 (a) shows an irradiated body virtually sliced into a plurality of layers in the depth direction, and FIG. 3 (b) shows a scanned image of a charged particle beam in one layer viewed from the depth direction. , Each is shown.

As shown in FIG. 3A, the irradiated body is virtually sliced into a plurality of layers in the irradiation depth direction, and in this example, from the deep layer (the range of the charged particle beam B is long). turn, the layer _{L 1,} the layer _{L 2,} ... layer _{L n-1,} layer _{L n,} a layer _{L n + 1,} ... layer _{L n-1,} are virtually slicing the layer _{L n} and n layer. Further, as shown in FIG. 3 (b), the charged particle beam B is irradiated to a plurality of irradiation spots of the layer L _n while drawing the beam trajectory TL (scan path). That is, the irradiation unit 2 is controlled by the control unit 7, and the charged particle beam B irradiated from the irradiation unit 2 moves on the beam trajectory TL.

When an error occurs during irradiation of the charged particle beam B, the control unit 7 stops the irradiation of the charged particle beam B. The control unit 7 stops the emission of the charged particle beam B from the accelerator 3 by turning on the beam chopper 16. Then, the control unit 7 stores the stop position of the charged particle beam B at the time of stop. After the error is resolved, the control unit 7 starts irradiating the charged particle beam B from the stored stop position. The error means that an abnormal value is detected by any monitor provided in the charged particle beam therapy device 1. The monitors include, for example, a detector that monitors the output (current value) of ions from the ion source, a detector that monitors the output of the charged particle beam B from the accelerator 3, various monitors in the irradiation nozzle 9, and the movement of the patient. Examples include detectors that detect. Further, the stop of the charged particle beam B is not limited to that by the beam chopper 16, and may be stopped by another method. For example, a shutter may be provided in the beam transport line 41, and the charged particle beam B may be physically shielded by the shutter.

Here, the charged particle beam therapy device 1 includes a power supply device 150 that supplies electric power to the scanning electromagnet 6 that scans the charged particle beam B irradiated to the tumor 14. The power supply device 150 includes an electromagnet power source 50 that supplies electric power to the scanning electromagnet 6, a cable 60 that connects the electromagnet power source 50 and the scanning electromagnet 6, and a current measuring unit 51 that measures a current. The cable 60 is crawled from the back side of the rotating gantry 5 and accommodated in a winding portion 55 provided on the back side of the rotating gantry 5 (see FIG. 1). The cable 60 crawls inside the rotating gantry 5 by a predetermined path and is connected to the scanning electromagnet 6 of the irradiation unit 2.

A detailed configuration of the power supply device 150 will be described with reference to FIGS. 4 to 6. FIG. 4 is a schematic view showing a configuration in the vicinity of a connection portion between the electromagnet power supply 50 and the cable 60 of the power supply device 150. FIG. 5 is a cross section of the cable 60. FIG. 6 is a circuit diagram of the power supply device 150.

As shown in FIGS. 4 and 5, the cable 60 includes a core wire (first wire) 61, an insulating material (first insulating material) 62, a shield (second wire) 63, and an insulating material (second wire). A second insulating material) 64 and the like.

The core wire 61 is made of a conductive material and connects the electromagnet power source 50 and the scanning electromagnet 6. The core wire 61 is connected to an output terminal (connection portion) 52 that supplies electric power in the electromagnet power supply 50. The periphery of the core wire 61 is covered with an insulating material 62. As a result, in the cable 60, the core wire 61 is insulated from the shield 63.

The shield 63 is provided so as to cover the periphery of the core wire 61. The shield 63 is composed of, for example, a conductive mesh member. The shield 63 is parallel to the first wire by connecting one end to the first wire (see FIG. 6). The end of the shield 63 on the electromagnet power supply 50 side is connected to the core wire 61 via the output terminal 52 in the electromagnet power supply 50. On the other hand, at the end of the shield 63 on the scanning electromagnet 6 side, the shield 63 is not connected to the core wire 61. That is, the shield 63 is not connected to the core wire 61 on the scanning electromagnet 6 side of the connection portion on the electromagnet power supply 50 side. With such a configuration, the shield 63 has the same potential as the core wire 61. The periphery of the shield 63 is covered with an insulating material 64. As a result, in the cable 60, the shield 63 is insulated from the outside.

As shown in FIG. 4, the insulating material 64 is removed from the cable 60 at the end on the electromagnet power supply 50 side. Further, the core wire 61 and the extension portion 63a of the shield 63 are separated from each other. In such a state, the current measuring unit 51 is connected to the core wire 61. The current measuring unit 51 is connected to the core wire on the scanning electromagnet 6 side of the output terminal 52, which is a connecting portion between the core wire 61 and the shield 63. The current measuring unit 51 measures the current of the core wire 61. On the other hand, the extension portion 63a of the shield 63 extends so as to bypass the current measurement portion 51 and is connected to the output terminal 52. As a result, the current measuring unit 51 can detect only the current flowing through the core wire 61 without detecting the current flowing through the shield 63.

With the above-described configuration, the insulating material 62 is provided between the core wire 61 and the shield 63 on the scanning electromagnet 6 side of the output terminal 52 which is the connection portion between the core wire 61 and the shield 63. And the shield 63 are insulated. The insulating material 64 is provided so as to cover the periphery of the shield 63. The insulating material 64 is connected to an installation potential member which is an installation potential. In the present embodiment, the installation potential member is, for example, an external structure, such as an installation surface 80 of a cable rack. That is, when the cable 60 is installed on the installation surface 80, the insulating material 64 is connected to the installation potential member.

Next, the circuit configuration of the power supply device 150 will be described with reference to FIG. As shown in FIG. 6, the core wire 61 extends from the output terminal 52 of the electromagnet power supply 50 to the load 70 (here, the scanning electromagnet 6). Further, a shield 63 having the same potential as the core wire 61 extends from the output terminal 52. The core wire 61 has a predetermined inductance L1. The shield 63 has a predetermined inductance L2.

Further, the core wire 61 and the shield 63 are adjacent to each other in the radial direction via the insulating material 62. Therefore, a distributed capacitance C1 is formed between the core wire 61 and the shield 63. Further, the shield 63 is arranged on the outer peripheral side of the core wire 61, and is adjacent to the external structure via the insulating material 64. The external structure is, for example, the installation surface 80 of the cable rack (see FIG. 5). Such a structure functions as an earth G with respect to the shield 63. As a result, the distributed capacitance C2 is formed between the shield 63 and the earth G.

Next, the actions and effects of the charged particle beam therapy device 1 and the power supply device 150 according to the present embodiment will be described.

First, the power supply device 200 according to the comparative example will be described with reference to FIG. 7. The power supply device 200 does not have a shield 63 like the power supply device 150 of this embodiment. Therefore, a capacitance distribution C3 is formed between the core wire 61 and the external structure. In this state, in addition to the current A2 flowing through the scanning electromagnet 6, the core wire 61 also generates a current A1 flowing through the capacitance distribution C3. Therefore, the current A1 also flows through the current measuring unit 51. In this case, the irradiation of the charged particle beam is stopped due to an error, and when the irradiation is started from the stop position, the current A1 flowing through the capacitance distribution C3 is generated, and the current measuring unit 51 also measures the current A1. As a result, an error occurs in the measurement result of the current measuring unit 51. If an error occurs in the measurement result in this way, the current value to the scanning electromagnet 6 when the irradiation of the charged particle beam is stopped cannot be accurately detected. This causes a problem that the stop position of the charged particle beam cannot be accurately grasped.

On the other hand, the charged particle beam therapy device 1 and the power supply device 150 according to the present embodiment include a core wire 61 for connecting the electromagnet power supply 50 and the scanning electromagnet 6, a shield 63 provided so as to cover the periphery of the core wire 61. To be equipped. By covering the circumference of the core wire 61 with the shield 63, a distributed capacitance C1 is formed between the core wire 61 and the shield 63. Further, a distributed capacitance C2 is formed between the shield 63 on the outer peripheral side and the external structure. Here, since the shield 63 is parallel to the core wire 61, the core wire 61 and the shield 63 have the same potential. Therefore, no current flows through the distributed capacitance C1 between the core wire 61 and the shield 63. On the other hand, a current A2 flows through the distributed capacitance C2 between the shield 63 and the external structure. However, the current A2 flows through the shield 63, but does not flow through the core wire 61. Therefore, it is possible to prevent the current A2 from flowing through the current measuring unit 51 connected to the core wire. The current measuring unit 51 can detect only the current A3 flowing from the core wire 61 to the scanning electromagnet 6. As a result, the measurement accuracy of the current value of the scanning electromagnet 6 can be improved. If the measurement accuracy can be improved in this way, the current value to the scanning electromagnet 6 when the irradiation of the charged particle beam is stopped can be accurately detected. As a result, the stop position of the charged particle beam can be accurately grasped.

The charged particle beam therapy device 1 and the power supply device 150 according to the present embodiment are provided between the core wire 61 and the shield 63 on the scanning electromagnet 6 side of the output terminal 52 which is a connection portion, and are provided between the core wire 61 and the shield 63. An insulating material 62 that insulates the shield 63 and a 64 that is provided so as to cover the periphery of the shield 63 are further provided. The insulating material 64 is connected to the installation surface (installation potential member) 80, which is the installation potential. As a result, the entire cable 60 (core wire 61 and shield 63) can be suitably insulated while improving the measurement accuracy of the current value of the scanning electromagnet 6.

The present invention is not limited to the above-described embodiment.

For example, the structure, connection mode, and the like of the power supply device 150 and the cable 60 are not limited to the above-described embodiments, and may be appropriately changed within the scope of the gist of the present invention.

Further, the configuration of the irradiation unit 2 is not limited to that shown in FIG. 2, and can be changed as appropriate.

1 ... charged particle beam therapy device, 2 ... irradiation unit, 3 ... accelerator, 6 ... scanning electromagnet, 14 ... tumor (irradiated body), 50 ... electromagnet power supply, 51 ... current measuring unit, 52 ... output terminal (connection unit) , 61 ... Core wire (first wire), 62 ... Insulating material (first insulating material), 63 ... Shield (second wire), 64 ... Insulating material (second insulating material), 80 ... Installation surface (Installation potential member), 150 ... Power supply device.

Claims (4)

A charged particle beam therapy device that irradiates an irradiated body with a charged particle beam.
A scanning electromagnet that scans the charged particle beam and
An electromagnet power supply that supplies power to the scanning electromagnet,
A first wire connecting the electromagnet power supply and the scanning electromagnet,
A second wire, which is provided so as to cover the periphery of the first wire and is parallel to the first wire by connecting one end on the electromagnet power supply side to the first wire.
A charge including a current measuring unit that is connected to the first wire on the scanning electromagnet side of the connecting portion between the first wire and the second wire and measures the current of the first wire. Particle beam therapy device. A first insulating material provided between the first wire and the second wire on the scanning electromagnet side of the connecting portion to insulate the first wire and the second wire.
A second insulating material provided so as to cover the periphery of the second wire is further provided.
The charged particle beam therapy apparatus according to claim 1, wherein the second insulating material is connected to an installation potential member which is an installation potential. A power supply device that supplies electric power to a scanning electromagnet that scans a charged particle beam that irradiates an irradiated object.
An electromagnet power supply that supplies power to the scanning electromagnet,
A first wire for connecting the electromagnet power supply and the scanning electromagnet,
A second wire, which is provided so as to cover the periphery of the first wire and is parallel to the first wire by connecting one end on the electromagnet power supply side to the first wire.
A power supply including a current measuring unit which is connected to the first wire on the scanning electromagnet side of the connecting portion between the first wire and the second wire and measures the current of the first wire. apparatus. A first insulating material provided between the first wire and the second wire on the scanning electromagnet side of the connecting portion to insulate the first wire and the second wire.
A second insulating material provided so as to cover the periphery of the second wire is further provided.
The power supply device according to claim 3, wherein the second insulating material is connected to an installation potential member which is an installation potential.

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