Toner density sensor for electrostatic copying machine
US4200388A · kind A · utility
3Cited by
2References
5Claims
0Family size
Assignee
Inventors
Key dates
| Filing date | Nov 16, 1977 |
| Grant date | Apr 29, 1980 |
| Priority date | — |
| Expiry date | Nov 16, 1997 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S222/01
- WIPO fieldOptics
- WIPO sectorInstruments
Abstract
A toner mixture comprising ferromagnetic carrier particles and non-magnetic toner particles are caused to flow through a conduit for measuring the toner density which is the ratio of toner particles to carrier particles in the mixture. The effective inductance of an electromagnetic coil disposed in the conduit varies in accordance with toner density. The coil is designed so that the magnetic lines of force thereof are substantially confined within the conduit and are not influenced by external bodies.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.