Particle beam rotational irradiation apparatus and particle beam therapy system

1. A particle beam rotational irradiation apparatus which radiates a charged particle beam in a rotatable manner around an irradiation target, comprising:

an irradiation nozzle that radiates the charged particle beam to the irradiation target;

a frame that supports the irradiation nozzle and rotates centering on an isocenter that is an irradiation reference for the charged particle beam;

an irradiation-nozzle support member that is provided on an inner-circumference side of the frame and supports the irradiation nozzle;

a movable floor that has a roller movable in a circumferential direction centering on a rotation axis of the frame;

a brake arranged to release or lock the roller to allow or prevent the roller from rotating; and

a movable-floor rail that is provided in the circumferential direction on the inner-circumference side of the frame, and supports the roller;

wherein the irradiation-nozzle support member includes a first coupling portion and the movable floor includes a second coupling portion and the first coupling portion is configured to be attachable/detachable to/from the second coupling portion during operation of the particle beam rotational irradiation apparatus in the circumferential direction centering on the rotation axis of the frame; and

a sensor configured to detect an attachment/detachment state of the first coupling portion and the second coupling portion for releasing or locking the brake.

2. The particle beam rotational irradiation apparatus of claim 1 , wherein the movable-floor rail has at its both ends, guide portions facing to the roller.

3. The particle beam rotational irradiation apparatus of claim 2 , wherein, when the movable floor is at a non-interfering position where it does not interfere with the irradiation nozzle, a face of the movable floor placed toward the rotation axis is positioned at a height that is the same or nearly the same as an upper face of an access floor on which a treatment table for moving the irradiation target toward the isocenter is placed.

4. The particle beam rotational irradiation apparatus of claim 2 , wherein the irradiation-nozzle support member has a planar portion extending in the inner-circumference side of the frame.

5. The particle beam rotational irradiation apparatus of claim 2 , further comprising a beam transport portion that rotates with the frame and leads the charged particle beam into the irradiation nozzle, wherein the beam transport portion has a plurality of bending magnets that are arranged so that a beam path of the charged particle beam is once deviated from a beam transport plane that includes the rotation axis of the frame and an irradiation axis of the irradiation nozzle and then returns to the beam transport plane again.

6. A particle beam therapy system comprising: a beam generation apparatus that generates a charged particle beam and accelerates the charged particle beam using an accelerator; a beam transport system that transports the charged particle beam accelerated by the accelerator; an irradiation nozzle that radiates the charged particle beam transported by the beam transport system to an irradiation target; and the particle beam rotational irradiation apparatus of claim 2 that mounts the irradiation nozzle therein.

7. The particle beam rotational irradiation apparatus of claim 1 , wherein, when the movable floor is at a non-interfering position where it does not interfere with the irradiation nozzle, a face of the movable floor placed toward the rotation axis is positioned at a height that is the same or nearly the same as an upper face of an access floor on which a treatment table for moving the irradiation target toward the isocenter is placed.

8. The particle beam rotational irradiation apparatus of claim 7 , wherein the irradiation-nozzle support member has a planar portion extending in the inner-circumference side of the frame.

9. The particle beam rotational irradiation apparatus of claim 7 , further comprising a beam transport portion that rotates with the frame and leads the charged particle beam into the irradiation nozzle, wherein the beam transport portion has a plurality of bending magnets that are arranged so that a beam path of the charged particle beam is once deviated from a beam transport plane that includes the rotation axis of the frame and an irradiation axis of the irradiation nozzle and then returns to the beam transport plane again.

10. A particle beam therapy system comprising: a beam generation apparatus that generates a charged particle beam and accelerates the charged particle beam using an accelerator; a beam transport system that transports the charged particle beam accelerated by the accelerator; an irradiation nozzle that radiates the charged particle beam transported by the beam transport system to an irradiation target; and the particle beam rotational irradiation apparatus of claim 7 that mounts the irradiation nozzle therein.

11. The particle beam rotational irradiation apparatus of claim 1 , wherein the irradiation-nozzle support member has a planar portion extending in the inner-circumference side of the frame.

12. The particle beam rotational irradiation apparatus of claim 11 , further comprising a beam transport portion that rotates with the frame and leads the charged particle beam into the irradiation nozzle, wherein the beam transport portion has a plurality of bending magnets that are arranged so that a beam path of the charged particle beam is once deviated from a beam transport plane that includes the rotation axis of the frame and an irradiation axis of the irradiation nozzle and then returns to the beam transport plane again.

13. A particle beam therapy system comprising: a beam generation apparatus that generates a charged particle beam and accelerates the charged particle beam using an accelerator; a beam transport system that transports the charged particle beam accelerated by the accelerator; an irradiation nozzle that radiates the charged particle beam transported by the beam transport system to an irradiation target; and the particle beam rotational irradiation apparatus of claim 11 that mounts the irradiation nozzle therein.

14. The particle beam rotational irradiation apparatus of claim 1 , further comprising a beam transport portion that rotates with the frame and leads the charged particle beam into the irradiation nozzle, wherein the beam transport portion has a plurality of bending magnets that are arranged so that a beam path of the charged particle beam is once deviated from a beam transport plane that includes the rotation axis of the frame and an irradiation axis of the irradiation nozzle and then returns to the beam transport plane again.

15. A particle beam therapy system comprising: a beam generation apparatus that generates a charged particle beam and accelerates the charged particle beam using an accelerator; a beam transport system that transports the charged particle beam accelerated by the accelerator; an irradiation nozzle that radiates the charged particle beam transported by the beam transport system to an irradiation target; and the particle beam rotational irradiation apparatus of claim 14 that mounts the irradiation nozzle therein.

16. A particle beam therapy system comprising: a beam generation apparatus that generates a charged particle beam and accelerates the charged particle beam using an accelerator; a beam transport system that transports the charged particle beam accelerated by the accelerator; an irradiation nozzle that radiates the charged particle beam transported by the beam transport system to an irradiation target; and the particle beam rotational irradiation apparatus of claim 1 that mounts the irradiation nozzle therein.

17. The particle beam rotational irradiation apparatus according to claim 1 , wherein the movable-floor rail is provided on less than 360° of the inner circumference side of the frame.