| 摘要 |
PURPOSE:To reduce the weight of a pressure fixing roller by providing it with a hollow cylindrical member made of ceramics and a metallic shaft member, and a space between them. CONSTITUTION:The pressure fixing roller has the shaft 7 made of a metal, such as steel, and the hollow cylindrical member 8 made of ceramics having a specific gravity of 3.4-3.9, a longitudinal elasticity coefficient of 2.7X10<6>-3.7X10<6>kg/cm<2>, and a surface hardness Hv of 1,200-1,800 (Vickers hardness), such as alumina, a mixture of alumina and zirconia, silicon nitride, or, silicon carbide, and a prescribed space (a) around the shaft 7. The presence of the space (a) effectively reduces the weight as compared with the case of using the solid body of a simple combination of the ceramic and metallic materials.
|
