Synchronization control device, synchronization control method and heavy particle beam emitting system

Abstract

To enable a synchronous drive for both rotation frames which support a heavy object when the two rotation frames are driven, and to accomplish a highly precise positioning.SOLUTION: A synchronization control device 6 includes: two circular-arc rails 14; two rotation frames 15 that support one supported member 7; two drive sources 16; two torque transmitting units 17; two displacement sensors 23 each being a component to form the torque transmitting unit 17 and measuring the displacement amount of a component that is displaced due to torque transmission; two lower control units 22 that control the respective drive sources 16 in such a way that the respective rotation frames 15 reach respective positions of target rotation angles which are input target position command values while performing a feedback for the measured displacement amounts measured by the respective displacement sensors 23; and two upper control units 21 which correct the respective target position command values based on a correction value table in which a correction value for correcting the target position command value is registered in advance, and which output, to the respective lower control units 22, the respective corrected target position command values.SELECTED DRAWING: Figure 8

Description

Technical Field

[0001] Embodiments of the present invention relate to synchronization control technology.

Background Art

[0002] When moving a plurality of rotating frames of a predetermined gantry with a plurality of drive shafts, it is necessary to perform synchronous operation of both drive shafts. However, due to factors such as mechanical differences, machining errors, and deformations of components, there is a possibility that the stop position of the rotating frame may have an error with respect to the target command position. Therefore, it is necessary to create a correction value table for each target command position and eliminate the position error. However, even if feedforward control using correction values is performed, there is a possibility that the position error of the rotating frame may not be eliminated due to aging deterioration. Therefore, it is necessary to periodically correct the correction value table, which causes a lot of trouble.

[0003] For example, in a two-axis synchronization control device, there is a known technique of using, as a correction value, the position error between the two axes when only one axis is servo-on and moved to a predetermined position. In this technique, it is possible to suppress the influence of an external force that interferes with the moving part due to the misalignment of the encoders in the all-axis type positioning control as the position control of each of the two axes. However, in this technique, since the correction value is set with one side being free-run, it cannot be applied to a mechanism that cannot be moved by only one axis. Also, from the viewpoint of driving only one side, it is necessary to perform the driving for updating the correction value separately from the actual operation. Furthermore, since the correction value is the relative position error between the two axes, when the absolute position of the main axis is shifted from the command position due to equipment error, the desired positioning cannot be achieved.

[0004] Also, there is a known technique of moving a moving part to a predetermined position by two-axis synchronous operation and then moving the moving part to a predetermined posture by moving each axis independently using a sensor that detects the posture of the moving part. At this time, the newly given command value for correction is used as the correction value, and during actual driving, this correction value is added to the position command value for positioning. In this technique, there are only two measurement positions for determining the correction value, lacking accuracy.

[0005] Furthermore, in a multi-axis synchronous control device, a technique is known in which axes are divided into a main axis and slave axes, the relative position error between the main axis and the slave axes is used as a correction value, and this correction value is added to the position command value to perform positioning. In this technique, since the correction value is the error in the relative position between the main axis and the slave axes, when the absolute position of the main axis is deviated from the commanded position due to a device error, the desired positioning cannot be achieved.

Prior Art Documents

Patent Documents

[0006]

Patent Document 1

Patent Document 2

Patent Document 3

Summary of the Invention

Problems to be Solved by the Invention

[0007] In a heavy particle beam irradiation system that has become popular in recent years, a high-weight irradiation port moves along a rail having an arc shape. For example, one irradiation port is attached to two rotating frames that move along two parallel arc-shaped rails. These rotating frames are driven by drive units connected to both side surfaces.

[0008] Also, a mechanism for driving the rotating frame using pin gears can be considered. For example, a mechanism can be considered in which a drive source is placed only on one side surface of one rotating frame, and two pin gears that mesh with both side surfaces of the two rotating frames are simultaneously rotated by a shaft. However, the shaft interferes with the irradiation port that moves together with the rotating frame.

[0009] Therefore, in a drive mechanism using two pinions, a mechanism can be considered in which two drive sources are placed, one on each side surface of two rotating frames, and two pinions meshing with the side surfaces of the rotating frames are synchronously controlled to rotate simultaneously. However, when driving the rotating frames, there is a risk of positional deviation between the two rotating frames due to a slight synchronization deviation between the two drive sources, and high-precision positioning control technology is required.

[0010] The problem to be solved by the present invention is to be able to drive both rotating frames synchronously and perform high-precision positioning when driving two rotating frames that support heavy objects.

Means for Solving the Problem

[0011] A synchronization control device according to an embodiment of the present invention includes at least two arc rails that are fixedly provided, form an arc shape, and are arranged such that their arcs are parallel to each other, at least two rotating frames that rotate along the arc rails about the center of the arc rails and support one supported portion, at least two drive sources that generate a torque for rotating the rotating frames, at least two torque transmission portions that are provided on the drive sources and transmit the torque to the rotating frames, at least two displacement sensors that are provided on the torque transmission portions and measure the displacement amount of the components that constitute the torque transmission portions and are displaced by the transmission of the torque, at least two lower control portions that control the drive sources so that the rotating frames reach a target position, which is an input target position command value, at a position of a target rotation angle while feeding back the displacement amount measured by the displacement sensors, and at least two upper control portions that correct the target position command value based on a correction value table in which correction values for correcting the target position command value are registered in advance and output the corrected target position command value to the lower control portions.

Brief Description of the Drawings

[0012]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Figure 18

Figure 19

Figure 20

Figure 21

MODE FOR CARRYING OUT THE INVENTION

[0013] (First Embodiment) Hereinafter, embodiments of a synchronization control device, a synchronization control method, and a heavy particle beam irradiation system will be described in detail with reference to the drawings. First, the first embodiment will be described with reference to FIGS. 1 to 9.

[0014] Reference numeral 1 in FIG. 1 is the heavy particle beam irradiation system of the present embodiment. This heavy particle beam irradiation system 1 is a so-called heavy particle beam cancer treatment device that irradiates a lesion tissue (cancer) of a patient P as an irradiation target with a heavy particle beam B that is a beam using carbon ions or the like as therapeutic radiation for treatment.

[0015] The radiation treatment technology using the heavy particle beam irradiation system 1 is called particle beam cancer treatment technology. This technology can pinpoint a cancer lesion (affected part) with carbon ions, damage the cancer lesion, and minimize damage to normal cells. Note that the heavy particle beam B is defined as a beam using an element heavier than a helium atom.

[0016] In addition, although this embodiment exemplifies the heavy particle beam B using carbon, other embodiments may also be used. For example, the heavy particle beam B using helium, oxygen, or neon may be used.

[0017] In cancer treatment using the heavy particle beam B, compared with conventional cancer treatment using X-rays, gamma rays, and proton beams, it has a higher ability to kill cancer lesions, a lower radiation dose on the surface of the patient P's body, and a characteristic that the radiation dose peaks at the cancer lesion. Therefore, the number of irradiations and side effects can be reduced, and the treatment period can be made shorter.

[0018] For example, when the heavy particle beam B passes through the body of the patient P, it loses kinetic energy and its speed decreases. At the same time, it is subject to a resistance that is approximately inversely proportional to the square of the speed, and when it decreases to a certain speed, it suddenly stops. The stopping point of this heavy particle beam B is called the Bragg peak, and high energy is released. The heavy particle beam irradiation system 1 can kill only the lesion tissue while suppressing damage to normal tissue by aligning this Bragg peak with the position of the lesion tissue (affected part) of the patient P.

[0019] The heavy particle beam irradiation system 1 includes an ion generator 2, an accelerator 3, a transport device 4, a slit-type irradiation device 5, a synchronization control device 6, and an irradiation port 7.

[0020] The ion generator 2 has an ion source for carbon ions which are charged particles, and the heavy particle beam B is generated by these carbon ions. The accelerator 3 accelerates the heavy particle beam B generated by the ion generator 2. The accelerator 3 includes a linear accelerator and a circular accelerator. Here, the heavy particle beam B is accelerated to about 70% of the speed of light while orbiting the circular accelerator about one million times. Then, the heavy particle beam B accelerated by the circular accelerator is transported to the slit-type irradiation device 5 by the transport device 4.

[0021] Note that the ion generator 2, the accelerator 3, and the transport device 4 are internally evacuated and are provided with a vacuum duct 8 (beam pipe) that extends integrally. The heavy particle beam B travels inside this vacuum duct 8. The vacuum duct 8 forms a transport path for guiding the heavy particle beam B from the ion generator 2 to the slit-type irradiation device 5. That is, the vacuum duct 8 is a sealed continuous space having a sufficient degree of vacuum to allow the heavy particle beam B to pass through.

[0022] Next, the slit-type irradiation device 5 will be described with reference to FIGS. 2 to 3. Note that the right side of the paper surface of FIG. 2 will be described as the front side (frontward side) of the slit-type irradiation device 5. When the direction in which the vacuum duct 8 of the transport device 4 extends and the direction in which the heavy particle beam B flies are defined as the X direction, the vertical direction of the paper surface orthogonal to this is defined as the Y direction, and the direction orthogonal to these is defined as the Z direction for the description.

[0023] First, a deflection electromagnet 52 is provided at the end of the vacuum duct 8 of the transport device 4. An enlarged duct 53 that spreads in a triangular shape (sector shape) when viewed from the side is provided from this deflection electromagnet 52. The enlarged duct 53 extends in the Y direction from the end of the vacuum duct 8 of the transport device 4. A main body 54 is connected to the tip of this enlarged duct 53. The main body 54 has a vertically long rectangular shape when viewed from the side. The inside of the enlarged duct 53 and the main body 54 is a sealed space having a degree of vacuum continuous from the vacuum duct 8 of the transport device 4.

[0024] Inside the main body 54, a number of deflection electromagnets 55 (FIG. 3) are provided that deflect the heavy particle beam B incident from a wide angular range and converge it to the isocenter C. These deflection electromagnets 55 generate an effective magnetic field region R (FIG. 2). The isocenter C is set as the position where the heavy particle beam B is most intensively irradiated, and the affected part of the patient P is placed at this isocenter C.

[0025] For example, a pair of deflection electromagnets 55 is provided inside the main body 54 in the Z direction. And two sets of deflection electromagnets 55 are arranged side by side in the Y direction. One effective magnetic field region R is generated by one set of deflection electromagnets 55. In the example of FIG. 2, two upper and lower effective magnetic field regions R can be generated by the upper and lower two sets of deflection electromagnets 55.

[0026] The effective magnetic field region R is generated so as to have a crescent shape when viewed from the side. By controlling the strength of the effective magnetic field region R, the trajectory of the heavy particle beam B can be controlled. The heavy particle beam B can be irradiated at an arbitrary angle around the isocenter C. For example, when the inclination of the reference trajectory when the heavy particle beam B is not deflected is set to 0 degrees, the irradiation angle of the heavy particle beam B can be changed over a range of a predetermined +θ degrees to -θ degrees around the isocenter C.

[0027] Note that the reference trajectory is the trajectory in which the heavy particle beam B flies straight from the vacuum duct 8 toward the isocenter C.

[0028] In the example of FIG. 2, the upper and lower two effective magnetic field regions R have the same shape and the same strength. That is, the upper and lower symmetric effective magnetic field regions R are generated, but other embodiments are also possible. For example, the effective magnetic field regions R may be asymmetric in the vertical direction. That is, the upper and lower two effective magnetic field regions R may have different shapes and strengths. Furthermore, an embodiment in which one effective magnetic field region R is generated on either the upper or lower side may also be possible. Note that the center of the range of the angle of the heavy particle beam B that varies in the circumferential direction around the isocenter C may be deviated from the reference orbit of the heavy particle beam B.

[0029] The patient P is placed on the movable mounting table 50. This movable mounting table 50 is supported by a moving arm 51, moves with the patient P placed thereon, and arranges the affected part of the patient P at the isocenter C. By moving this movable mounting table 50, the patient P can be moved to the irradiation position of the heavy particle beam B for alignment. Therefore, the heavy particle beam B can be irradiated with optimal accuracy to the lesion tissue of the patient P.

[0030] The front side of the main body 54 is a concave portion 56 that is recessed in a semicircular shape in a side view. The isocenter C is set at the center of the semicircle of this concave portion 56, and the patient P is arranged at this isocenter C. Here, the movable mounting table 50 can enter the concave portion 56 on the front side of the main body 54 with the patient P and be arranged at the isocenter C. For example, the movable mounting table 50 on which the patient P is placed can enter from the front direction of the slit type irradiation device 5 (the direction of the white arrow D in FIG. 2). In this way, the patient P can be made to enter from an appropriate direction and arranged at the isocenter C.

[0031] A slit 57 is formed on the front side of the main body 54 so as to extend in the circumferential direction around the isocenter C where the patient P is arranged. For example, a vertically long slit 57 (FIG. 3) is formed. The slit type irradiation device 5 emits the heavy particle beam B at an arbitrary angle from this slit 57 toward the isocenter C. Note that the slit 57 is closed with a super heat-resistant and super cold-resistant polyimide film, and the vacuum inside the main body 54 is maintained in a state where the heavy particle beam B can pass through.

[0032] In the vicinity of the slit-type irradiation device 5, an irradiation port 7 capable of changing the irradiation direction of the heavy particle beam B with respect to the isocenter C is provided. This irradiation port 7 is equipped with a ridge filter, a position monitor, a dose monitor, and a scanning electromagnet. Thus, the irradiation port 7 is a heavy object equipped with a number of devices.

[0033] This irradiation port 7 moves circumferentially at a position equidistant from the isocenter C around the isocenter C where the patient P is placed.

[0034] For example, when the inclination of the reference orbit of the heavy particle beam B is set to 0 degrees, the irradiation port 7 can move within a range from a predetermined +θ degrees to -θ degrees. For example, the irradiation port 7 can be rotated by a predetermined angle in each of the two directions in the circumferential direction. This irradiation port 7 moves along an arc rail 14 (FIG. 4) having a C shape in a side view provided in the synchronization control device 6 (FIG. 4).

[0035] The irradiation port 7 moves along the shape (boundary shape) of the exit side of the effective magnetic field region R in a side view. The heavy particle beam B traveling from the exit side of the effective magnetic field region R toward the isocenter C passes through the irradiation port 7, and the traveling direction of the heavy particle beam B is finely adjusted by the irradiation port 7.

[0036] In FIGS. 2 to 3, for the sake of understanding, the X direction of the slit-type irradiation device 5 is shown in a state where it coincides with the horizontal direction. However, when actually installing the slit-type irradiation device 5, as shown in FIG. 4, the entire slit-type irradiation device 5 is tilted. For example, it is installed on the floor surface F in a state where the longitudinal direction (Y direction) of the main body 54 is inclined.

[0037] In this embodiment, the upper part of the main body 54 is tilted so as to face the patient P. The irradiation range of the heavy particle beam B is an arbitrary angular range centered on the isocenter C, but due to the inclination of the slit-type irradiation device 5, the heavy particle beam B can be irradiated from directly above the patient P.

[0038] That is, the slit type irradiation device 5 is installed in an inclined state such that the reference orbit when the orbit of the heavy particle beam B is not deflected by the slit type irradiation device 5 is inclined from the horizontal direction (horizontal axis). By doing so, the range of the angle at which the heavy particle beam B is irradiated to the patient P, which is the irradiation target of the heavy particle beam B, becomes practical.

[0039] In addition, in the present embodiment, the upper part of the main body 54 of the slit type irradiation device 5 is inclined so as to face the patient P, but the upper part of the main body 54 may be inclined so as to be away from the patient P. Further, the slit type irradiation device 5 may be used without being inclined.

[0040] Next, the synchronization control device 6 of the first embodiment will be described with reference to FIGS. 4 to 9. A synchronization control method is implemented using this synchronization control device 6. Note that, in the description, the right side of the paper surface in FIGS. 4 to 6 is defined as the front side (frontward side) of the synchronization control device 6. Also, in FIG. 7, the left side of the paper surface is defined as the left side of the synchronization control device 6, and the right side of the paper surface is defined as the right side of the synchronization control device 6.

[0041] As shown in FIG. 4, the synchronization control device 6 is a device for moving the irradiation port 7 in an arc shape along the inner peripheral surface of the recess 56 of the slit type irradiation device 5. Note that this recess 56 is located on the front side of the main body 54 as shown in FIG. 2. The irradiation port 7 moves within the range where the slit 57 (FIG. 3) of the slit type irradiation device 5 is provided, and finely adjusts the heavy particle beam B emitted from the slit 57.

[0042] As shown in FIG. 7, the synchronization control device 6 is a device having left - right symmetry. Here, the members and devices arranged on the left side of the synchronization control device 6 are referred to as the first unit 10A, and the members and devices arranged on the right side of the synchronization control device 6 are referred to as the second unit 10B. The first unit 10A and the second unit 10B have the same configuration. When moving the irradiation port 7, the first unit 10A and the second unit 10B perform the same operation and are controlled so that their operations coincide, that is, are synchronized.

[0043] The synchronous control device 6 includes two support structures 11. These support structures 11 form a wall shape, with their bottoms fixed to the floor surface F, and they stand upright side by side with a predetermined interval. A plurality of beam members 12 are spanned between the left and right support structures 11.

[0044] Furthermore, the synchronous control device 6 includes one port base 13, two arc rails 14, two rotating frames 15, two drive sources 16, two torque transmission parts 17, and two angle sensors 18.

[0045] In the following description, the members and devices corresponding to the first unit 10A may be referred to as the first arc rail 14A, the first rotating frame 15A, the first drive source 16A, the first torque transmission part 17A, and the first angle sensor 18A. Also, the members and devices corresponding to the second unit 10B may be referred to as the second arc rail 14B, the second rotating frame 15B, the second drive source 16B, the second torque transmission part 17B, and the second angle sensor 18B.

[0046] The port base 13 is a plate-shaped member that supports the irradiation port 7 as a supported part. The irradiation port 7 is fixed at the center of this port base 13.

[0047] The arc rail 14 is a member that is fixedly provided by the support structure 11, forms an arc shape, and is arranged such that their arcs are parallel to each other.

[0048] The rotating frame 15 is guided by the arc rail 14 and rotates within a predetermined rotation angle range with the center of the arc rail 14 as the axis (central axis J (Figure 7)). The two left and right rotating frames 15 are fixed to the left and right sides of the port base 13. That is, one irradiation port 7 is supported by the two rotating frames 15. Note that the central axis J of the arc rail 14 extends in the horizontal direction and includes the isocenter C. As the rotating frame 15 rotates, the irradiation port 7 rotates around the isocenter C. The first rotating frame 15A and the second rotating frame 15B rotate around the same (one) central axis J.

[0049] The drive source 16 is a device that is fixedly provided by the support structure 11 and generates torque for rotating the rotary frame 15 along the arc rail 14. The drive source 16 is, for example, a motor.

[0050] The torque transmission unit 17 is a device that is fixedly provided by the support structure 11 and is provided in the vicinity of the drive source 16, and transmits the torque generated by the drive source 16 to the rotary frame 15. The drive source 16 and the torque transmission unit 17 are connected by a timing belt 19 for torque transmission.

[0051] The angle sensor 18 is provided on the rotary frame 15. The angle sensor 18 is a device that detects the inclination of the rotary frame 15 and the rotation angle when the rotary frame 15 rotates. When the rotary frame 15 rotates (moves) along the arc rail 14, the position of the rotary frame 15 on the arc rail 14 can be specified by the rotation angle detected by the angle sensor 18. In the following description, the rotation angle detected by the angle sensor 18 may be referred to as the absolute position of the rotary frame 15.

[0052] As shown in FIG. 4, the arc rail 14 and the rotary frame 15 form a C shape in which a part of a circle is cut out in a side view. The side view is a view from a direction intersecting the front-rear direction of the synchronization control device 6 and coincides with the direction in which the central axis J extends. The opening dimension of the cut-out portion of the arc rail 14 and the rotary frame 15 is set to a dimension that allows the patient P as an object to enter from a direction intersecting (orthogonal) to the central axis J of the arc rail 14 when the patient P is arranged near the irradiation port 7. In this way, the patient P can be made to enter from an appropriate direction (the direction of the white arrow D in FIG. 4) and be arranged at the isocenter C on the central axis J of the arc rail 14.

[0053] As shown in FIG. 5, when moving the irradiation port 7 above the patient P to irradiate the heavy particle beam B from above the patient P, the rotary frame 15 rotates (moves) upward along the arc rail 14.

[0054] As shown in FIG. 6, when moving the irradiation port 7 obliquely downward of the patient P to irradiate the heavy particle beam B from obliquely downward of the patient P, the rotary frame 15 rotates (moves) downward along the arc rail 14.

[0055] As shown in FIG. 4, a plurality of beam members 12 connecting the left and right support structures 11 are provided at the front and bottom of the support structures 11. And between the left and right support structures 11, the main body 54 of the slit type irradiation device 5 is provided. This main body 54 is disposed at the rear of the support structure 11. Further, the vertical dimension of the main body 54 is larger than the vertical dimension of the support structure 11.

[0056] Since the main body 54 of the slit type irradiation device 5 is disposed at the rear of the support structure 11, the beam members 12 connecting the left and right support structures 11 cannot be provided at the rear of the support structure 11. Therefore, it is difficult to ensure the rigidity of the rear part of the support structure 11. In this case, for example, it is necessary to correct so that no displacement occurs at the stop positions of the left and right rotary frames 15.

[0057] Next, the system configuration of the synchronization control device 6 will be described with reference to the block diagram shown in FIG. 8. Note that the arrows in FIG. 8 are an example showing the flow of data including predetermined values or signals, and there may be a flow of data other than the arrows. Also, necessarily, the order of each process is not fixed, and the order of some processes may be interchanged. Also, some processes may be executed in parallel with other processes. Further, the synchronization control device 6 may include components other than those shown in FIG. 8, or some of the components shown in FIG. 8 may be omitted.

[0058] In addition to the above-described configuration, the synchronization control device 6 includes one control computer 20, two upper control units 21, two lower control units 22, two displacement sensors 23, and one origin return result integration unit 24.

[0059] In the following description, the device corresponding to the first unit 10A may be referred to as the first upper control unit 21A, the first lower control unit 22A, and the first displacement sensor 23A. Also, the device corresponding to the second unit 10B may be referred to as the second upper control unit 21B, the second lower control unit 22B, and the second displacement sensor 23B.

[0060] The control computer 20 is a device that controls the synchronization control device 6 in response to a user's input operation. For example, the control computer 20 outputs a target position command value to the upper control unit 21 in response to a user's input operation. The target position command value is a value indicating the rotation angle (absolute position) that is the target for reaching the rotation frame 15.

[0061] Note that the angle sensor 18 is connected to the control computer 20 and sends the measured rotation angle of the rotation frame 15 to the control computer 20. The control computer 20 can determine whether the rotation frame 15 has reached the position of the target position command value based on the rotation angle detected by the angle sensor 18.

[0062] The upper control unit 21 includes a correction value table storage unit 25 that stores a correction value table in which correction values for correcting the target position command value are registered in advance. The upper control unit 21 is a device that corrects the target position command value based on the correction value table stored in the correction value table storage unit 25 and outputs the corrected target position command value to the lower control unit 22.

[0063] Also, the upper control unit 21 has hardware resources such as a processor and a memory, and is configured as a computer in which software-based information processing is realized using the hardware resources by the CPU (Central Processing Unit) executing various programs. The upper control unit 21 is configured by, for example, a PLC (Programmable Logic Controller). Furthermore, the synchronization control method of the present embodiment is realized by causing a computer, the upper control unit 21, to execute various programs.

[0064] As shown in FIG. 9, in the correction value table, correction values are registered for respective rotation angles when the rotation frame 15 rotates, in association with respective target position command values. In the correction value table, correction values corresponding to the first rotation frame 15A and correction values corresponding to the second rotation frame 15B are registered every 10 degrees of the rotation angle. Note that in FIG. 9, for ease of understanding, the correction value table stored in the first upper control unit 21A and the correction value table stored in the second upper control unit 21B are shown as one correction value table.

[0065] The correction value is a value indicating a correction rotation angle necessary to cause the rotation frame 15 to reach the target position when the rotation frame 15 does not actually reach the target position due to factors such as distortion of the arc rail 14, machining error, and deformation due to aging deterioration.

[0066] For example, assume that "10 degrees" is input as the target position command value from the control computer 20 to the first upper control unit 21A and the second upper control unit 21B. Here, the first upper control unit 21A outputs a value obtained by adding "-0.25 degrees" to "10 degrees" to the first lower control unit 22A based on the correction value table. On the other hand, the second upper control unit 21B outputs a value obtained by adding "+0.05 degrees" to "10 degrees" to the second lower control unit 22B based on the correction value table.

[0067] Note that in this embodiment, "addition" includes a mode of adding a negative value. For example, "addition" includes a mode of subtracting the absolute value of a predetermined value.

[0068] Also, when the correction value corresponding to the target position command value is not registered in the correction value table, an interpolation value calculated from the vicinity before and after the target position command value may be used. For example, assume that "15 degrees" is input as the target position command value from the control computer 20 to the first upper control unit 21A and the second upper control unit 21B. Here, the correction value corresponding to the target position command value of "15 degrees" is not registered in the correction value table. Therefore, the first upper control unit 21A calculates "+0.025 degrees", which is an intermediate value between "-0.25 degrees", the correction value of "10 degrees", and "+0.30 degrees", the correction value of "20 degrees", as the correction value (interpolation value). On the other hand, the second upper control unit 21B calculates "+0.075 degrees", which is an intermediate value between "+0.05 degrees", the correction value of "10 degrees", and "+0.10 degrees", the correction value of "20 degrees", as the correction value (interpolation value).

[0069] As shown in FIG. 8, the lower control unit 22 is a device that controls the drive source 16 based on the input target position command value. The lower control unit 22 is, for example, a driver for the drive source 16. The corrected target position command value from the upper control unit 21 is input to the lower control unit 22.

[0070] The displacement sensor 23 is provided in the torque transmission unit 17 and is a device that measures the displacement amount of a component that constitutes the torque transmission unit 17 and is displaced by torque transmission. The displacement sensor 23 is, for example, a resolver incorporated in the torque transmission unit 17. The displacement sensor 23 measures the rotation amount of a predetermined component such as the transmission shaft (not shown) of the torque transmission unit 17.

[0071] Also, the lower control unit 22 controls the drive source 16 so that the rotation frame 15 reaches the position of the target rotation angle, which is the input target position command value, while feeding back the displacement amount measured by the displacement sensor 23.

[0072] For example, the measured value (displacement amount) of the first displacement sensor 23A of the first torque transmission unit 17A is input to the first lower control unit 22A. The first lower control unit 22A grasps the movement amount of the first rotation frame 15A based on the input measured value, and drives the first drive source 16A until the first rotation frame 15A reaches the target position on the first arc rail 14A.

[0073] On the other hand, the measured value (displacement amount) of the second displacement sensor 23B of the second torque transmission unit 17B is input to the second lower control unit 22B. The second lower control unit 22B grasps the movement amount of the second rotation frame 15B based on the input measured value, and drives the second drive source 16B until the second rotation frame 15B reaches the target position on the second arc rail 14B.

[0074] The origin return result integration unit 24 is a device that performs a process of adding the value of the origin offset to the target position command value when an origin offset for setting a control origin that can be arbitrarily set by the user at a position different from the mechanical origin unique to the device is performed. In this way, the value of the origin offset can be reflected in the target position command value, and the accurate positioning of the rotation frame 15 can be performed. This origin return result integration unit 24 is connected to the control computer 20 and is controlled by the control computer 20.

[0075] Note that the origin "0 degrees" registered as the target position command value in the correction value table (Figure 9) is the control origin. When the value of the origin offset is not reflected in the correction value, the upper control unit 21 adds the value of the origin offset to the correction value. Then, each upper control unit 21 outputs the corrected target position command value to each lower control unit 22.

[0076] Each lower control unit 22 controls each drive source 16 based on the input corrected target position command value, and causes the rotation frame 15 to reach the position of the target rotation angle. Since each drive source 16 is controlled based on the corrected target position command value, each rotation frame 15 can be stopped at an accurate position.

[0077] In the first embodiment, when driving the two rotating frames 15 that support the irradiation port 7, which is a heavy object, both rotating frames 15 can be driven synchronously, and the irradiation port 7 can be positioned with high precision. Then, the heavy particle beam B can be accurately irradiated from the irradiation port 7 to the affected part of the patient P.

[0078] (Second Embodiment) Next, the second embodiment will be described with reference to FIGS. 10 to 15. Note that the same reference numerals are given to the same components as those shown in the above-described embodiment, and redundant descriptions are omitted.

[0079] As shown in FIG. 10, each upper control unit 21 of the second embodiment includes a feedback adjustment unit 26 and a correction value update unit 27 in addition to the configuration of the first embodiment described above. Further, the synchronization control device 6 of the second embodiment includes an angle deviation detection unit 30 in addition to the configuration of the first embodiment described above.

[0080] The feedback adjustment unit 26 determines whether there is a difference (first difference) between the target rotation angle targeted by the target position command value and the actual rotation angle (absolute position) detected by the angle sensor 18. Then, the feedback adjustment unit 26 adjusts the target position command value of the rotating frame 15 so that this difference falls within a predetermined range (first threshold). Further, the correction value update unit 27 updates the correction value registered in the correction value table of the corresponding rotating frame 15 based on the adjusted target position command value when the difference (first difference) falls within the predetermined range. In this way, it is possible to adjust the difference (first difference) caused by factors such as aging deterioration, and it is possible to automatically update the correction value table.

[0081] The angular deviation detection unit 30 calculates the difference (second difference) in the rotation angles of the first rotating frame 15A and the second rotating frame 15B based on the rotation angles (absolute positions) detected by the first angle sensor 18A and the second angle sensor 18B while the rotating frame 15 is rotating. Then, when this difference exceeds a predetermined threshold value (second threshold value), the angular deviation detection unit 30 is a device that performs a process of stopping the rotation of the first rotating frame 15A and the second rotating frame 15B. In this way, when a problem occurs in the rotation of the first rotating frame 15A and the second rotating frame 15B, the first rotating frame 15A and the second rotating frame 15B can be safely stopped. This angular deviation detection unit 30 is connected to the control computer 20 and is controlled by the control computer 20. Note that the threshold value is set in advance by the user.

[0082] As shown in FIG. 11, the first angle sensor 18A is fixed to the first rotating frame 15A, and the second angle sensor 18B is fixed to the second rotating frame 15B. Here, the rotation angles (absolute positions) detected by the first angle sensor 18A and the second angle sensor 18B may be different. Since the target position command value is a specific one rotation angle, when the rotation angles of the left and right rotating frames 15 are different, there will be the aforementioned difference (first difference or second difference) in both or either one of the rotating frames 15.

[0083] First, the feedback adjustment unit 26 adjusts the target position command value of the rotating frame 15 based on the measured value (rotation angle) of the angle sensor 18 so that the difference (first difference) falls within a predetermined range. For example, as shown in FIG. 12, the rotation of the first rotating frame 15A with insufficient rotation is advanced, and the rotation of the second rotating frame 15B with excessive rotation is suppressed for adjustment. The feedback adjustment unit 26 adjusts (corrects) the target position command value so that the difference (first difference) is eliminated by this adjustment. Note that an arbitrary range for making the difference (first difference) fall within is set in advance by the user.

[0084] When the adjustment by the feedback adjustment unit 26 is successful, the correction value update unit 27 updates the correction value table. For example, the correction value update unit 27 calculates the adjustment amount of the correction value adjusted by the feedback adjustment unit 26 based on the target position command value before correction input from the control computer 20 and the target position command value adjusted by the feedback adjustment unit 26. Then, the correction value update unit 27 adds the calculated adjustment amount to the corresponding correction value in the correction value table stored in the correction value table storage unit 25 and registers it in the correction value table as a new correction value. This updated correction value table is stored in the correction value table storage unit 25.

[0085] FIG. 13 is a graph of an approximate function schematically showing the relationship between the target position command value before correction and the target position command value after correction (the amount corrected by the correction value). As shown in this graph, when there are a plurality of correction values, the relationship between the target position command value before correction and the target position command value after correction can be represented by a predetermined correction function. If there is a correction value that greatly deviates from this correction function, that correction value may not be correct. The correction value updated by the correction value update unit 27 will approach this correction function. Also, the correction value update unit 27 may perform a process of updating the correction value table so that the correction value approaches the correction function.

[0086] Also, when the adjustment by the feedback adjustment unit 26 cannot be performed, the angle deviation detection unit 30 stops the rotation of both rotation frames 15. For example, when the difference in the rotation angles of the first rotation frame 15A and the second rotation frame 15B (the second difference) exceeds a predetermined threshold value, the angle deviation detection unit 30 stops the rotation of both rotation frames 15.

[0087] Next, the synchronization control process will be described using the flowchart of FIG. 14. Refer to the block diagram shown in FIG. 10. The following steps are at least a part of the processes included in the synchronization control process, and other steps may be included in the synchronization control process.

[0088] First, in step S1, the control computer 20 inputs the target position command value (before correction) to the upper control unit 21.

[0089] In the next step S2, the origin return result integration unit 24 adds the value of the origin offset to the target position command value input from the control computer 20.

[0090] In the next step S3, the upper control unit 21 acquires the corresponding correction value based on the correction value table stored in the correction value storage unit 25.

[0091] In the next step S4, the upper control unit 21 adds the acquired correction value to the target position command value to which the origin offset value has been added.

[0092] In the next step S5, the corrected target position command value is input from the upper control unit 21 to the lower control unit 22.

[0093] In the next step S6, the lower control unit 22 executes drive control processing. Here, the lower control unit 22 controls the drive source 16 based on the corrected target position command value and continues the drive control processing until the rotating frame 15 reaches the position indicated by the target position command value. The lower control unit 22 ends the drive control processing when the rotating frame 15 reaches the position indicated by the target position command value.

[0094] In the next step S7, the feedback adjustment unit 26 determines whether the difference (first difference) between the target rotation angle (position) targeted by the target position command value and the actual rotation angle (absolute position) detected by the angle sensor 18 is within a predetermined range (first threshold). Here, if the difference is within the predetermined range (YES in step S7), the synchronization control process is completed. On the other hand, if the difference is not within the predetermined range (NO in step S7), the process proceeds to step S8.

[0095] In the next step S8, the origin return result integration unit 24 adds the value of the origin offset to the target position command value input from the control computer 20.

[0096] In the next step S9, the upper control unit 21 inputs, to the feedback adjustment unit 26, a value obtained by subtracting (or adding) the measured value (rotation angle) of the angle sensor 18 of the corresponding rotation frame 15 from the target position command value to which the origin offset value is added. If the value input to the feedback adjustment unit 26 includes the origin offset value, the origin offset value is subtracted from this input value so that the origin offset value is not added twice.

[0097] In the next step S10, the upper control unit 21 acquires a correction value corresponding to the target position command value to which the origin offset value is added, based on the correction value table stored in the correction value storage unit 25.

[0098] In the next step S11, the upper control unit 21 adds the acquired correction value to the target position command value from which the measured value (rotation angle) of the angle sensor 18 is subtracted (or added).

[0099] In the next step S12, the upper control unit 21 inputs the corrected target position command value to the lower control unit 22.

[0100] In the next step S13, the lower control unit 22 executes the drive control process again. The lower control unit 22 ends the drive control process when the rotation frame 15 reaches the position indicated by the target position command value.

[0101] In the next step S14, the correction value update unit 27 updates the correction value registered in the correction value table of the corresponding rotation frame 15, based on the correction value newly generated by the processes from step S8 to step S12. Then, the synchronization control process is completed.

[0102] Next, the angle deviation detection process will be described using the flowchart of FIG. 15. Refer to the block diagram shown in FIG. 10. The following steps are at least part of the processes included in the angle deviation detection process, and other steps may be included in the angle deviation detection process.

[0103] First, in step S21, the angle deviation detection unit 30 determines whether the rotation frame 15 is rotating. Here, if the rotation frame 15 is not rotating (NO in step S21), the angle deviation detection process is completed. On the other hand, if the rotation frame 15 is rotating (YES in step S21), the process proceeds to step S22.

[0104] In the next step S22, the angle deviation detection unit 30 calculates the difference (second difference) in the rotation angles of the first rotation frame 15A and the second rotation frame 15B based on the rotation angles (absolute positions) detected by the first angle sensor 18A and the second angle sensor 18B.

[0105] In the next step S23, the angle deviation detection unit 30 determines whether the calculated difference exceeds a predetermined threshold value (second threshold value). Here, if the difference does not exceed the predetermined threshold value (NO in step S23), the angle deviation detection process is completed. On the other hand, if the difference exceeds the predetermined threshold value (YES in step S23), the process proceeds to step S24.

[0106] In the next step S24, the angle deviation detection unit 30 executes an emergency stop process to stop the rotation of the rotation frame 15 while it is rotating.

[0107] In the second embodiment, since the angle deviation detection unit 30 is provided, it is possible to avoid equipment damage due to the left - right angle deviation of the rotation frame 15 during synchronous control.

[0108] Also, since the correction value update unit 27 is provided, the correction value table is updated every time it is driven, and it can be kept in the latest state, eliminating the need for the user to separately perform a test for updating the correction value table.

[0109] (Third Embodiment) Next, a third embodiment will be described with reference to FIGS. 16 to 21. Note that the same components as those shown in the above-described embodiments are denoted by the same reference numerals, and redundant descriptions thereof are omitted.

[0110] As shown in FIG. 16, each upper control unit 21 of the third embodiment includes a feedback adjustment unit 26 and a correction value update unit 27, similarly to the configuration of the second embodiment described above. Further, the synchronization control device 6 of the third embodiment includes, in addition to the configuration of the first embodiment described above, a home position return control unit 31, two home sensors 32 (FIG. 17), and two pairs of limit sensors 33 (FIG. 17).

[0111] In the following description, the devices corresponding to the first unit 10A may be referred to as the first home sensor 32A and the first limit sensor 33A. Also, the devices corresponding to the second unit 10B may be referred to as the second home sensor 32B and the second limit sensor 33B.

[0112] As shown in FIG. 17, the home sensors 32 are provided on the respective arc rails 14. These home sensors 32 detect the upper end portions of the rotating frames 15 that have reached the mechanical home positions unique to the devices. For example, as shown in FIG. 18, in the first arc rail 14A, when the upper end portion of the first rotating frame 15A reaches the first home position Q1 (mechanical home position), the first home sensor 32A detects the arrival. Also, as shown in FIG. 19, in the second arc rail 14B, when the upper end portion of the second rotating frame 15B reaches the second home position Q2 (mechanical home position), the second home sensor 32B detects the arrival.

[0113] As shown in FIG. 16, the home position return control unit 31 performs control for returning the rotating frame 15 to the mechanical home position. This home position return control unit 31 is connected to the control computer 20 and is controlled by the home position return control unit 31.

[0114] The origin return result integration unit 24 of the third embodiment detects the positional deviation between the mechanical origin and the position (absolute position) of the actual rotation angle detected by the angle sensor 18 when the rotation frame 15 returns to the origin. For example, there may be an origin offset in which a software origin Qf (control origin) that can be arbitrarily set by the user is set at a position different from the first origin Q1 (mechanical origin) and the second origin Q2 (mechanical origin). Here, there may be a positional deviation between the first origin Q1 and the second origin Q2. When this origin offset is performed, the origin return result integration unit 24 performs a process of adding the value of the origin offset and the value of the positional deviation to the target position command value.

[0115] As shown in FIG. 17, the limit sensors 33 are provided on the side surfaces of the respective arc rails 14. These limit sensors 33 detect the upper end or the lower end of the rotation frame 15 that has reached the end of the rotatable range. The limit sensors 33 indicate the boundary of the movable range of the rotation frame 15. For example, the first arc rail 14A is provided with a pair of upper and lower first limit sensors 33A provided near one and the other ends. The second arc rail 14B is provided with a pair of upper and lower second limit sensors 33B provided near one and the other ends.

[0116] Note that since the attachment work of the origin sensor 32 and the limit sensor 33 to the arc rail 14 is performed manually by the operator, the attachment positions on the left and right may be slightly deviated. For example, the first origin Q1 defined by the first origin sensor 32A of the first arc rail 14A and the second origin Q2 defined by the second origin sensor 32B of the second arc rail 14B may not necessarily be the same and may be deviated. Similarly, the attachment positions of the first limit sensor 33A and the second limit sensor 33B may not necessarily be the same and may be deviated. Therefore, in the third embodiment, the origin return process is executed.

[0117] Next, the home return process will be described with reference to the flowchart of FIG. 21. Refer to the block diagram shown in FIG. 16. The following steps are at least part of the processes included in the home return process, and other steps may also be included in the home return process.

[0118] Here, during the home return process, the first rotation frame 15A and the second rotation frame 15B are always in a synchronous operation, but each one of them is in a mode of returning to the origin. For example, the first rotation frame 15A returns to the origin first, and then the second rotation frame 15B returns to the origin.

[0119] First, in step S31, the home return control unit 31 inputs a target position command value with the first origin Q1 as the target position to the first lower control unit 22A and the second lower control unit 22B. Then, the execution of the home return of the first rotation frame 15A is started. Here, the first rotation frame 15A and the second rotation frame 15B move to the position of the first origin Q1 (FIG. 18).

[0120] In the next step S32, when the first rotation frame 15A and the second rotation frame 15B move to the position of the first origin Q1 (FIG. 18), the home return control unit 31 completes the home return of the first rotation frame 15A.

[0121] In the next step S33, the home return control unit 31 inputs a target position command value with the second origin Q2 as the target position to the first lower control unit 22A and the second lower control unit 22B. Then, the execution of the home return of the second rotation frame 15B is started. Here, the first rotation frame 15A and the second rotation frame 15B move to the position of the second origin Q2 (FIG. 19).

[0122] In the next step S34, when the first rotation frame 15A and the second rotation frame 15B move to the position of the second origin Q2 (FIG. 19), the home return control unit 31 completes the home return of the second rotation frame 15B.

[0123] In the next step S35, the origin return control unit 31 executes origin teaching. Here, the software origin Qf in the target position command value of the rotation frame 15 is set (FIG. 20). For example, the origin return result integration unit 24 sets the value obtained by adding the origin offset value to the first origin Q1 as the software origin Qf, and sets the value obtained by adding the origin offset value to the second origin Q2 as the software origin Qf.

[0124] Note that the correction value update unit 27 updates the correction value table based on the origin offset value obtained by the origin return result integration unit 24.

[0125] In the third embodiment, the value of the origin offset and the value of the positional deviation can be reflected in the target position command value, and the irradiation port 7 can be accurately positioned.

[0126] As described above, the present invention has been described based on the first to third embodiments. However, the configuration applied in any of the embodiments may be applied to other embodiments, or the configurations applied in each embodiment may be combined.

[0127] In the above-described embodiments, the determination of any value (first difference, second difference) using a reference value (range, threshold value) may be a determination of "whether or not the arbitrary value is greater than or equal to the reference value". Further, this determination may be a determination of "whether or not the arbitrary value exceeds the reference value". Further, this determination may be a determination of "whether or not the arbitrary value is less than or equal to the reference value". Further, this determination may be a determination of "whether or not the arbitrary value is less than the reference value". Also, the reference value may not be fixed but may change. Therefore, instead of the reference value, a value within a predetermined range may be used, and it may be determined whether or not an arbitrary value falls within the predetermined range. Further, the error generated in the device may be analyzed in advance, and a predetermined range including the error range centered on the reference value may be used for the determination.

[0128] In the above flowchart, an example is shown where each step is executed in series. However, the sequence of the steps is not necessarily fixed, and the sequence of some steps may be reversed. Also, some steps may be executed in parallel with other steps.

[0129] Note that the program executed by the above-described synchronization control device 6 is provided by being pre-embedded in a ROM or the like. Additionally or alternatively, this program is provided by being stored in a computer-readable non-transitory storage medium as an installable or executable file. This storage medium includes a CD-ROM, a CD-R, a memory card, a DVD, a flexible disk (FD), and the like.

[0130] Also, the program executed by this synchronization control device 6 may be stored in a computer connected to a network such as the Internet and provided by being downloaded via the network. That is, the program may be provided from the resources of cloud computing. Also, a server on the cloud may execute the program and only the processing result thereof may be provided via the cloud.

[0131] Note that the number of members and devices provided in the synchronization control device 6 is not limited to the above-described embodiment and may be appropriately changed. For example, the number of arc rails 14 may be not only two but also three or more. Also, the number of upper control units 21 may be not only two but also three or more.

[0132] According to at least one of the embodiments described above, the upper control unit 21 corrects the target position command value based on the correction value table and outputs the corrected target position command value to the lower control unit 22. Thereby, when driving the two rotating frames 15 that support the heavy object, both rotating frames 15 can be driven synchronously and highly accurate positioning can be achieved.

[0133] Although some embodiments of the present invention have been described, these embodiments are presented by way of example and are not intended to limit the scope of the invention. These embodiments can be implemented in various other forms, and various omissions, replacements, changes, and combinations can be made without departing from the gist of the invention. These embodiments or their modifications are included in the scope and gist of the invention, as well as in the invention described in the claims and the equivalent scope thereof.

Explanation of Reference Numerals

[0134] 1... Heavy particle beam irradiation system, 2... Ion generator, 3... Accelerator, 4... Transport device, 5... Slit type irradiation device, 6... Synchronization control device, 7... Irradiation port, 8... Vacuum duct, 10A... First unit, 10B... Second unit, 11... Support structure, 12... Beam member, 13... Port base, 14... Arc rail, 14A... First arc rail, 14B... Second arc rail, 15... Rotating frame, 15A... First rotating frame, 15B... Second rotating frame, 16... Drive source, 16A... First drive source, 16B... Second drive source, 17... Torque transmission part, 17A... First torque transmission part, 17B... Second torque transmission part, 18... Angle sensor, 18A... First angle sensor, 18B... Second angle sensor, 19... Timing belt, 20... Control computer, 21... Upper control part, 21A... First upper control part, 21B... Second upper control part, 22... Lower control part, 22A... First lower control part, 22B... Second lower control part, 23... Displacement sensor, 23A... First displacement sensor, 23B... Second displacement sensor, 24... Origin return result integration part, 25... Correction value storage part, 26... Feedback adjustment part, 27... Correction value update part, 30... Angle deviation detection part, 31... Origin return control part, 32... Origin sensor, 32A... First origin sensor, 32B... Second origin sensor, 33... Limit sensor, 33A... First limit sensor, 33B... Second limit sensor, 50... Moving mounting table, 51... Moving arm, 52... Deflection electromagnet, 53... Expansion duct, 54... Main body, 55... Deflection electromagnet, 56... Recess, 57... Slit, B... Heavy particle beam, C... Isocenter, D... White arrow, F... Floor surface, J... Central axis, P... Patient, Q1... First origin, Q2... Second origin, Qf... Software origin, R... Effective magnetic field region.

Claims

1. At least two arc-shaped rails that are fixedly provided, form an arc shape, and are arranged such that their arcs are parallel to each other, At least two rotating frames that rotate along the arc-shaped rails about the center of the arc-shaped rails and support one supported part, At least two drive sources that generate torque for rotating the rotating frames, At least two torque transmission parts provided on the drive sources for transmitting the torque to the rotating frames, At least two displacement sensors provided on the torque transmission parts, which are components constituting the torque transmission parts and measure the displacement amount of the components that are displaced by the transmission of the torque, At least two lower control parts that control the drive sources so that the rotating frames reach the target position command value, which is the input target position and the position of the target rotation angle, while feeding back the displacement amount measured by the displacement sensors, At least two upper control parts that correct the target position command value based on a correction value table in which correction values for correcting the target position command value are registered in advance and output the corrected target position command value to the lower control parts, Comprising Synchronous control device.

2. The arc-shaped rails and the rotating frames form a C shape, The opening dimensions of the cut-out parts of the arc-shaped rails and the rotating frames are such that the object can enter from a direction intersecting the axis of the center of the arc-shaped rails when the object is arranged near the supported part, The synchronous control device according to Claim 1.

3. At least two angle sensors provided on the rotating frames for detecting the inclination of the rotating frames and the rotation angle when the rotating frames rotate, Based on there being a difference between the rotation angle targeted by the target position command value and the actual rotation angle detected by the angle sensor, at least two feedback adjustment units that adjust the target position command value of the rotation frame so that the difference falls within a predetermined range; At least two correction value update units that update the correction value registered in the correction value table of the corresponding rotation frame based on the adjusted target position command value when it falls within the range; Comprising; The synchronization control device according to claim 1 or claim 2.

4. At least two angle sensors provided on the rotation frame that detect the rotation angle when the rotation frame rotates, which is the inclination of the rotation frame; During the rotation of the rotation frame, based on the rotation angle detected by the angle sensor, calculate the difference in the rotation angles of the two rotation frames, and based on the difference exceeding a predetermined threshold value, an angle deviation detection unit that stops the rotation of the rotation frame; Comprising; The synchronization control device according to claim 1 or claim 2.

5. Comprising an origin return result integration unit that adds the value of the origin offset to the target position command value based on the origin offset being performed to set a control origin that can be arbitrarily set by the user at a position different from the mechanical origin inherent to the device; The synchronization control device according to claim 1 or claim 2.

6. At least two angle sensors provided on the rotation frame that detect the rotation angle when the rotation frame rotates, which is the inclination of the rotation frame; At least two origin sensors provided on the arc rail that detect the rotation frame that has reached the mechanical origin inherent to the device; An origin return control unit that controls the origin return to bring the rotation frame to the mechanical origin; Based on the fact that the origin has been restored, a position deviation between the mechanical origin and the position of the actual rotation angle detected by the angle sensor is detected, and an origin offset integration unit that adds the value of the origin offset and the value of the position deviation to the target position command value is performed based on the fact that an origin offset for setting a control origin that can be arbitrarily set by the user at a position different from the mechanical origin has been performed. Comprising The synchronization control device according to claim 1 or claim 2.

7. At least two arc rails that are fixedly provided, form an arc shape, and are arranged so that their arcs are parallel to each other. At least two rotating frames that rotate along the arc rail around the center of the arc rail and support one supported part. At least two drive sources that generate torque to rotate the rotating frame. At least two torque transmission parts provided on the drive source for transmitting the torque to the rotating frame. At least two displacement sensors provided on the torque transmission part for measuring the displacement amount of the parts that constitute the torque transmission part and are displaced by the transmission of the torque. At least two lower control parts that control the drive source so that the rotating frame reaches the position of the target rotation angle, which is the input target position command value, while feeding back the displacement amount measured by the displacement sensor. At least two upper control parts that output the target position command value to the lower control part. A method performed using The upper control part Corrects the target position command value based on a correction value table in which a correction value for correcting the target position command value is registered in advance. Outputs the corrected target position command value to the lower control part. Synchronization control method.

8. The synchronization control device according to claim 1 or claim 2, and An ion generator that generates a heavy particle beam, An accelerator that accelerates the heavy particle beam generated by the ion generator, An irradiation port as the supported part for irradiating the heavy particle beam accelerated by the accelerator toward an object to be irradiated, comprising A heavy particle beam irradiation system.

Images