US4147127A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Toner concentration detecting apparatus
Assignee: Hitachi Ltd
•
Filing: 1977-10-13
•
Granted: 1979-04-03
•
Expires: 1997-10-13
Abstract
Abstract A detecting coil is placed in the flow of a developer (developing agent) including a magnetic carrier and a coloring toner, which is fed by developer-feeding means. The detecting coil is shaped in a flat plate in a direction perpendicular to the coil axis, which in turn is substantially at right angles to the direction of the flow of the developer.
Inventors
- 👤 Isamu Terashima
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-24 08:38
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G15/0822; G03G15/0848; G03G15/0849; G03G15/0853
Claims Analysis
Total Claims: 7
Claim 1
Independent Claim
144 words
In an apparatus used with a developing apparatus for detecting the concentration of a toner comprised in a developer, said detecting apparatus comprising developer feeder means and said developer including a magnetic carrier and a coloring toner, said developer feeding means including a fixed permanent magnet and a non-magnetic sleeve rotatably mounted around the outer periphery of said permanent magnet, said developing apparatus being adapted for image development by use of a developer magnet brush made of said permanent magnet, the improvement further comprising at least one detecting coil magnetically acting upon said developer, said detecting coil being formed in a flat plate perpendicular to the axis thereof, said detecting coil being located in the flow of said developer in such a manner that said coil axis intersects with the direction of the flow of said developer substantially at right angles to each other.
Claim 2
Dependent Claim
144 words
In an apparatus used with a developing apparatus for detecting the concentration of a toner comprised in a developer, said detecting apparatus comprising developer feeder means and said developer including a magnetic carrier and a coloring toner, said developer feeding means including a fixed permanent magnet and a non-magnetic sleeve rotatably mounted around the outer periphery of said permanent magnet, said developing apparatus being adapted for image development by use of a developer magnet brush made of said permanent magnet, the improvement further comprising at least one detecting coil magnetically acting upon said developer, said detecting coil being formed in a flat plate perpendicular to the axis thereof, said detecting coil being located in the flow of said developer in such a manner that said coil axis intersects with the direction of the flow of said developer substantially at right angles to each other.
Claim 3
Dependent Claim
36 words
A toner concentration-detecting apparatus according to claim 1, in which a plurality of said detecting coils are arranged at predetermined spacial intervals to each other with the axes thereof perpendicular to the flow of said developer.
Claim 4
Dependent Claim
34 words
A toner concentration-detecting apparatus according to claim 1, in which said detecting coil is located in selected one of the positions on and in the vicinity of the polar line of said permanent magnet.
Claim 5
Dependent Claim
27 words
A toner concentration-detecting apparatus according to claim 1, in which the axis of said detecting coil is substantially in parallel to the rotational axis of said sleeve.
Claim 6
Dependent Claim
61 words
A toner concentration-detecting apparatus according to claim 1, in which detecting coils are mounted on a common support and the assembly of said detecting coils and the common support is removably mounted on a case containing said developer from outside of said case in such manner that the detecting coils are inserted through apertures provided in said case into said developer.
Claim 7
Dependent Claim
19 words
A toner concentration-detecting apparatus according to claim 5, in which the detecting coils and common support are formed integrally.
References Cited (Backward Citations)
US3058405A
Cited
US3802381A
Cited
US3572551A
Cited
US3892672A
Cited
US3932034A
Cited
US3893408A
Cited
US3999687A
Cited
US4054230A
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1982-04-02 | 1982-10-02 | 1983-04-03 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1986-04-02 | 1986-10-02 | 1987-04-03 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1990-04-02 | 1990-10-02 | 1991-04-03 | $7700.00 | Window Closed / Lapsed |