发明名称 |
Electrostatic copying apparatus |
摘要 |
First and second sensors (37), (39) are provided in a developing tank (36) containing a liquid developer consisting of a liquid carrier or dispersant and toner particles dispersed in the carrier. The first sensor (37) measures the electrical resistivity of the developer whereas the second sensor (39) measures the optical transmissibility thereof. Additional toner is supplied into the developer to maintain the transmissivity at a value which is a predetermined function of the resistivity. The transmissibility value is reduced as the resistivity increases, thereby maintaining the copy image density constant. The first sensor (37) includes two electrodes immersed in the developer and an A.C. or D.C. voltage is applied thereacross. The current flow through the electrodes (37) and thereby the developer is measured to determine the resistivity of the developer. Where the applied voltage is D.C., an arrangement is provided to mechanically scrape accumulated developer off the electrodes (37) at intermittent intervals.
|
申请公布号 |
US4310238(A) |
申请公布日期 |
1982.01.12 |
申请号 |
US19800181609 |
申请日期 |
1980.08.27 |
申请人 |
RICOH COMPANY, LTD. |
发明人 |
MOCHIZUKI, MANABU;MIYAKAWA, SEIICHI;KIMURA, TARO;HASHIMOTO, JUNICHIRO |
分类号 |
G03G15/10;(IPC1-7):G03G15/00 |
主分类号 |
G03G15/10 |
代理机构 |
|
代理人 |
|
主权项 |
|
地址 |
|