Measuring toner level in a closed container
US6600882B1 · kind B1 · utility
Assignee
Inventors
Key dates
| Filing date | Oct 17, 2002 |
| Grant date | Jul 29, 2003 |
| Priority date | — |
| Expiry date | Oct 17, 2022 |
Classification
- Technology area (CPC G)Physics
- CPC primaryG03G15/0872
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
Toner (5) is measured in a toner cartridge (1) by compressing the air in the upper part (7) of the toner hopper (3). The result of the compression is observed by a diaphragm (13) or, alternatively, by a pressure transducer (25). The volume of air is inversely proportional to the resonant frequency of diaphragm (13) or the pressure at pressure transducer (25). This is converted by control system (23) using direct equations or table look-up of empirical data. The diaphragm (13) carries a magnet (15), which is driven by coil (19) from the imaging device and then frequency of current induced by magnet (15) is then sensed by coil (19). Uneven toner piling is not a significant factor in the results measured.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.