Patent Number: 051732483
Section: claims

1. A remote control apparatus for maintaining a tokamak type nuclear fusion reactor comprising a vessel having a torus space formed therein and a plurality of maintenance ports extending radially for communicating said torus space with the outside of said vessel, and in-vessel components arranged in said vessel, comprising: a rail having generally similarly arcuated links pivoted to one after another and extendable in the circumferential directions in said torus space, said links forming, in said torus space, a continuous semi-circular arc having a center substantially coincident with a center of said torus space when said links are extended;  a vehicle carrying at least one manipulator for handling said in-vessel components and guided along said rail extended in said torus space;  rail housing means arranged outside of said vessel, for housing said rail when said remote control device is not used;  rail mounting means supporting the last link of said rail and delivering, into said torus space, said links housed in said rail housing means from the first link to the last link in succession through one of the maintenance ports and causing the links to form the continuous semi-circular arc; and  a rail supporting device inserted in said torus space through another maintenance port adjacent to the first mentioned maintenance port, for supporting a central portion of said rail.  controlling means for controlling said mechanisms in position, speed and force;  monitoring means for monitoring said mechanisms in operating force and position, and for signaling a measured data to monitor the operating condition of said mechanisms;  performing changeover means for changing the operating mode of said controlling means to change the rigidity of the position control for said mechanisms depending on the monitored operating condition of said mechanisms; and  generating command means for generating commands to correct said mechanisms in position, speed and force depending on the monitored operating condition of said mechanisms. 2. An apparatus according to claim 1, wherein said rail comprises a plurality of joints for preventing the adjacent arcuated links from rotating inwardly thereof and allowing said adjacent arcuated links to rotate outwardly, and said rail housing means guides said arcuated links in a folded state on one after another by rotating said arcuated links outwardly around the respective joints. 3. An apparatus according to claim 1, wherein said rail mounting means comprises a fixed guide fixed at the outside of said torus space at a position on a line extended from said one maintenance port, slide links slidable in said one maintenance port and a rail carriage movable along said slide links for sending said arcuated links in succession from said rail housing means into said torus space through said one maintenance port. 4. An apparatus according to claim 3, wherein one of said slide links is a second link driven along said fixed guide and the other link is a first link driven along said second link and having guide means for sending said arcuated links in said one maintenance port. 5. An apparatus according to claim 4, wherein said first link has an end close to said torus space and a support arm drivingly pivoted to said end, said rail carriage has fixed thereto a swing link pivoted by means of one of said joints to the arcuated link which is sent to said torus space last, for supporting said rail via said joint which is sent last when said rail is extended to form a continuous arc in said torus space. 6. An apparatus according to claim 5, wherein said first slide link has a guide groove for housing rollers and a roller holder driven along said guide groove, for causing said rollers of said rail to slide in said guide groove for a predetermined stroke (A). 7. An apparatus according to claim 5, wherein said vehicle is detachably mounted on said support arm and has driving means for moving said arcuated links along said arc defined by the extended arcuated links. 8. An apparatus according to claim 5, wherein said swing link is intermittently driven for sending said arcuated links from said rail housing means to said first slide link, said roller holder reciprocates in said guide groove in synchronism with said swing link, and said driving means for moving said vehicle are driven in synchronism with said swing link and said roller holder. 9. An apparatus according to claim 1, wherein said rail has a plurality of mechanical locking mechanisms for locking the adjacent arcuated links so as not to be pivoted when said adjacent links form an arc, and said vehicle has operating means for actuating said mechanical locking mechanisms. 10. An apparatus according to claim 9, wherein each of said mechanical locking mechanisms comprises a hook having a support shaft pivoted to an end of one of the adjacent two arcuated links, said support shaft being provided with a projection extending toward an inner side of said one arcuated link, and said operating means has a recess engaging with said projection. 11. An apparatus according to claim 1, wherein said rail has a projection formed on an outer periphery of the arcuated link adjacent to said another maintenance port, and said rail supporting device comprises a base disposed at the outside of said torus space, a slide link reciprocating along said base in said another maintenance port and having a distal end which is accessible to said rail when said slide link is advanced, and a pair of holding members provided on said distal end of said slide link, for firmly holding said projection of said rail. 12. An apparatus according to claim 11, wherein said distal end of said slide link has a guide roller for supporting an undersurface of the respective arcuated link of said rail moved in an circumferential direction of said torus space in said torus space when said rail is extended in said torus space, said guide roller being selectively moved to a position at which said roller supports said respective arcuated link and to a position remote from said respective arcuated link. 13. An apparatus according to claim 1, further comprising an in-vessel component transporting device disposed below said rail supporting device, for transporting said in-vessel components from an interior of said torus space to the outside thereof and from the outside of said torus space to said interior thereof through said another maintenance port. 14. An apparatus according to claim 1, wherein said vehicle is detachably provided with another manipulator and a transporting device transports said another manipulator. 15. An apparatus according to claim 1, wherein said vehicle is movable over the whole length of said rail extended in said torus space, and comprises a frame having an inner passage, an opening for preventing interference with said joints of said rail and said projection adapted to be held by the paired holding members and a plurality of wheels rolling on an outer surface of said rail. 16. An apparatus according to claim 15, wherein said vehicle driving means has a servo motor and a pinion driven by said servo motor, and said arcuated links are provided in an inner surface thereof with a rack engageable with said pinion. 17. An apparatus according to claim 1, further comprising a cable system comprising cable means connected to said vehicle, for supplying a power to said vehicle from the outside thereof and transmitting signals between said vehicle and an external control device, a cable drum disposed at the outside of said torus space, for taking up and taking off said cable means, a drive roller rotatably mounted on said rail carriage, for moving said cable means in a direction according to a position of said swing link, and a plurality of cable supports mounted on the respective joints, for taking up and taking off said cable means. 18. An apparatus according to claim 3, wherein said swing link firmly supports a distal end portion of an arcuated link at a distal end of another rail extended through said another maintenance port after the last arcuated link has been sent into said torus space so as to form a circular rail assembly together with the first mentioned rail in said torus space. 19. An apparatus according to claim 18, wherein said vehicle is moved along said first mentioned rail and said another rail. 20. An apparatus according to claim 1, further comprising a plurality of driving mechanisms with servo motors at least for extending and restoring the rail and for handling said in-vessel components, and a control device for said plurality of driving mechanisms, said control device including: 21. An apparatus according to claim 1, wherein said vehicle carries a manipulator having a telescopic arm and an actuator for swinging said telescopic arm in a plane perpendicular to said rail. 22. An apparatus according to claim 2, further comprising rotatable rollers coaxially provided under said joints, said rail housing means having a guide groove for guiding said rollers, and said guide groove being formed in a circular form.