| 摘要 |
PROBLEM TO BE SOLVED: To reduce the weight of a large roller made of ceramics while securing its rigidity by forming an outer peripheral part made of ceramics into a hollow cylinder and providing a reinforcing means. SOLUTION: An outer peripheral part 2 made of ceramics is formed into a hollow cylinder by using alumina, zirconia, etc., and a reinforcing member 8 is provided inside the outer peripheral part 2. The reinforcing member 8 is a reinforcing means for reinforcing the rigidity of the outer peripheral part made of ceramics and is a disc-shaped body which is formed into an integral structure with the outer peripheral part 2 and has the same core as that of the outer peripheral part. One or a plurality of holes 9 for reducing weight are provided in the reinforcing member 8 to reduce its weight. Moreover, a material having substantially equal coefficient of thermal expansion to that of the material of the outer peripheral part 2, for example, titanium, a titanium material, is used. As for a material of a shaft 3, titanium or titanium alloy having substantially equal expansion coefficient to that of the material of the outer peripheral part 2 made of ceramics is used. Consequently, since the outer peripheral part 2 and the shaft 3 are expanded and shrunk simultaneously at the same rate when temperature of a large roller LR made of ceramics is changed, the peeling and deviation of a joint part 4 do not occur. |
