Toner end detection device and method
US5621221A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Dec 22, 1994 |
| Grant date | Apr 15, 1997 |
| Priority date | — |
| Expiry date | Dec 22, 2014 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G2215/0894
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
An apparatus and method for detecting an empty condition of toner cartridges containing toner for copiers, fax machines, printers and the like is disclosed. The cartridges may be mounted to a rotary developing device. According to one embodiment, when a toner cartridge has been rotatably positioned to a developing position, an empty condition is detected by emitting light into the toner cartridge and detecting the light coming out of its bottom. To accomplish this detection, a light source and a light sensor are fixedly located near a bottom corner of the toner cartridge at the developing position. Light is emitted into the toner cartridge at a predetermined oblique angle with respect to a side wall of the toner cartridge. Light exits out from the bottom wall if a predetermined amount of toner does not exist in the toner cartridge. Due to the oblique angle, the distance between the light source and the light sensor is substantially reduced and provides an accurate measurement. This reduced distance also results in a smaller end detection system.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.