| 摘要 |
PURPOSE:To obtain a nonmagnetic single component system not affected with the humidity, by applying the negative pressure to numbers of vent holes provided at the outer circumference part of a developer supply means by means of a sucking means for adsorption of the developer and then supplying the develper to an electrostatic image holder. CONSTITUTION:A case 3 of a developing device 2 is set close to a photosensitive drum 1 with its aperture part 3a set opposite to the drum 1, and a development roller 6 consisting of a cylinder 7 containing numbers of vent holes 9 is set in the case 3. The cylinder 7 is turned, and at the same time a compressor 10 functioning as a sucking means is actuated. As a result, the toner 5 is forcibly stuck to the surface of the cylinder 7. Thus the toner 5 can be supplied to the drum 1 regardless of the humidity. In addition, the sticking force of the toner can be varied to the cylinder 7 by changing the sucking force of the compressor 10. As a result, the concentration of an image can be controlled. |
