| 摘要 |
PURPOSE:To form a lightweight magnet roll and obtain high characteristics by making a magnet piece of a plastic magnet and magnetizing it so that magnetic paths are formed from the external surface to both flanks. CONSTITUTION:Magnet pieces 2 fitted to the outer circumference of a roll shaft are made of plastic magnets molded by injection, and the magnet pieces 2 are magnetized so that magnetic paths are each formed so that magnetic paths are formed from the outer circumferential surface 2b to both flanks 2c in a section while the shapes and magnetization states of the magnet pieces 2 are uniform and highly precise. Consequently, the magnet roll for the magnetic brush development of a dry type electronic copying machine is lightweight and manufactured easily, and it has high characteristics, i.e., high surface magnetic flux density and uniform magnetic flux distribution. |
