| 摘要 |
<p>PURPOSE: To keep nip width almost uniform all over the roller by making the outside diameter of an elastic layer at the central part larger than the diameter of the elastic layer at the end part. CONSTITUTION: A roller main body 3 is constituted by providing the flexible elastic layer on the outer circumference of a shaft. The outside diameter D1 of the roller main body 3 at the center part is made larger than the outside diameter D2 at the end part. The shaft is arranged in the core part of the roller along the axial length direction, and the shaft is formed into a columnar shape and formed out of a metal, or resin material. As for the roller main body 3, the central part has the outside diameter D1 =ϕ20.4mm, and the end part has the outside diameter D2 =ϕ20.1mm, D1 is made larger than D2 . The difference between both diameters, the diameter difference (D1 -D2 )=0.3mm, is designed based on an extent how the center part floats up and the flexibility extent of the elastic layer, then, the nip width of the roller main body 3 with reference to the photoreceptor drum is made almost uniform in the length direction.</p> |
