| 摘要 |
PURPOSE:To obtain a toner powder of a sharp particle size distribution in good efficiency, by feeding grinding feeds to 1st and 2nd classification means and to 1st and 2nd grinding means through specified routes and feeding the ground product of the coarse powder from the 2nd grinding means to the 2nd classification means. CONSTITUTION:A powder feed is fed from a feed hopper 1 through a feed supply pipe 2 to a 1st classifier 3, and the classified coarse powder from the 1st classifier 3 is fed to a grinder 4, ground, and re-fed through the pipe 2 to the 1st classifier 3. On the other hand, the classified fine powder from the 1st classifier 3 is fed to a collection cyclone 6 and collected, withdrawn from the cyclone with an injection feeder 7, fed through a pipe 8 to a 2nd classifier 9 and classified. The classified coarse powder from the 2nd classifier 9 is reground in a 2nd grinder 13, and the ground product from the 2nd grinder is fed through a pipe 14 to the 1st classifier 3 together with the feed and the ground product from the 1st grinder. The classified fine powder from the 1st classifier 3 is further classified with the 2nd classifier 9, and the coarse powder from the 2nd classifier 9 is ground with the 2nd grinder and re-fed to the 2nd classifier 9. |
