| 摘要 |
1,213,493. Developing electrostatic images. RANK XEROX Ltd. March 20, 1968 [March 23, 1967], No. 13513/68. Heading G2H. An apparatus for dispensing toner particles 52 comprises a guide 39 to direct developer 36 comprising carrier and toner particles in a path towards a development zone, a roller 40 having a core 45 and a cover 47 of a material having tribolectric characteristics similar to the carrier particles, a hopper enclosing toner particles above the roller 40, such that upon rotation of the roller toner particles are dispensed from the hopper in an amount to replace toner particles depleted from the carrier particles 39. The transfer of toner particles 52 from the roller 40 to the carrier particles in the developer 36 continuing until such time as the electrostatic attraction between the carrier and toner particles equals that between the cover 47 and toner particles. A variable D. C. potential 70 connected to the core 45 varies the electrostatic attraction of toner to the cover 47, to control the toner concentration in the developer and so provides selective development of images. |
