| 摘要 |
PURPOSE:To prevent generation of a defective image of a first copy by starvation of a toner by providing a control means for impressing a developing bias to a developing means and detecting the residual amt. of the toner at the point of the time before the first image is formed. CONSTITUTION:This image forming device is mounted with an antenna type detecting means 13 for the residual amt. of the toner which detects the residual amt. of the toner in a developing device 4. Said means is constituted of a developing sleeve 8, an antenna 14 disposed in parallel therewith and a resistor R provided between the antenna 14 and the earth. The control means 18 impresses the developing bias to the developing sleeve 8 at the time of the power source supply which is the point of the time before the first image is formed. The residual amt. of the toner is thereby detected at the point of the time before the first copy is formed even if the antenna type detecting means 13 for the residual amt. of the toner is used. The generation of the defective image of the first copy by the toner starvation is, therefore, prevented. |
