| 摘要 |
PROBLEM TO BE SOLVED: To provide a control rod drive mechanism having a guide tube which allows a control rod to ascend/descend smoothly and can be easily fabricated.SOLUTION: A control rod drive mechanism 10 according to an embodiment includes: a cylindrical guide tube 11; an ascending/descending member 12 provided so as to be able to ascend/descend in the guide tube 11; a piston 15 placed on the ascending/descending member 12 and connected to a control rod 8; and a plurality of rollers 41 provided on the outer peripheral part of the ascending/descending member 12 and the outer peripheral part of the piston 15 respectively. The guide tube 11 has: a first guide tube body 50 including a pair of first circumferential ends 51 extending in the axial direction; a second guide tube body 60 including a pair of second circumferential ends 61 in contact with the corresponding first circumferential ends 51; and a guide part 70 arranged between a pair of the rollers 41 to guide the rollers 41 in the axial direction. The guide part 70 is formed integrally with the first guide tube body 50. |
