| 摘要 |
PURPOSE:To detect the remaining amount of toner without imposing physical load and having the effect of light on the toner by providing a signal projecting means and a signal detecting means for detecting the signal of the light, a sound wave and a radio wave in an area where the toner is not sensitized. CONSTITUTION:This device is provided with a toner tank 21 where the toner 22 is stored, the signal projecting means 26 which is provided at an upper part than the upper surface of the toner in the toner tank 21 and projects the signal of the light, the sound wave and the radio wave in the area where the toner 22 is not sensitized, and the signal detecting means 27 which is installed on a base inside the toner tank 21 and detects the signal of the light, the sound wave and the radio wave in the area where the toner 22 is not sensitized from the means 26. In a state where the toner 22 exists in the toner tank 21, the light, the sound wave and the radio wave in the area where the toner 22 is not sensitized from the means 26 are not detected by the means 27. However, the intensity of the signal received by the means 27 gets higher as the toner 22 is decreased. Thus, the remaining amount of the toner 22 is detected and known. |
