| 摘要 |
PROBLEM TO BE SOLVED: To steadily form a good quality image by preventing displacement of each of the magnetic poles of a magnet roller by securely fixing the magnet roller and metal core of a developing roller to each other. SOLUTION: The magnet roller 41 having fixed magnetic poles, of the developing roller 31 is formed by extrusion molding. The periphery of the metal core 43 which is pressed into the magnet roller 41 formed by extrusion molding is axially provided with a groove 47. Before the inside diameter of the magnet roller 41 formed by extrusion molding completely contracts , the metal core 43 is pressed into the roller 41. Thereby, part of the internal surface of the magnet roller 41 contracting due to the change of the inside diameter over time is bitten into the groove 47 of the metal core 43. COPYRIGHT: (C)2004,JPO |
