Patent US4956668A successfully refreshed from Google Patents.
US4956668A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Developer mix monitoring for replaceable developer stations
Assignee: Eastman Kodak Co
•
Filing: 1988-07-05
•
Granted: 1990-09-11
•
Expires: 2008-07-05
Abstract
Abstract A toner monitor in an electrostatographic machine is automatically calibrated when a new replaceable development station is loaded into the machine. The detected toner concentration in the development station is used by the monitor as a reference signal against which future readings are compared. The reference signal is reset upon machine power-up to correspond to the detected toner concentration in the development station, but only when there is a fresh development station in the machine. Resetting the reference signal only when there is a fresh development station prevents erroneous reference signals which would result if the developer mix concentration was other than perfect at power-down.
Inventors
- 👤 Kenneth A. Arnold
- 👤 Wunan Chang
- 👤 Kelly S. Robinson
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-01 16:12
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G15/0896; G03G15/0822; G03G15/0848; G03G15/0849; G03G15/0853
Claims Analysis
Total Claims: 17
Claim 1
Independent Claim
121 words
An electrostatographic machine comprising: means for receiving replaceable development stations of the type having (1) a chamber containing a developer mix of carrier particles and toner powder in a predetermined desired concentration and (2) means for indicating whether the developer mix in the development station is fresh; means for producing a signal representative of the concentration of toner powder in the developer mix in the chamber; means for setting a reference signal; means for sensing the indicating means of a received development station for determining if the development mix therein is fresh; and means, operable only upon determining that the developer mix in the received development is fresh, for adjusting the reference signal until it substantially equals the toner concentration signal.
Claim 2
Dependent Claim
121 words
An electrostatographic machine comprising: means for receiving replaceable development stations of the type having (1) a chamber containing a developer mix of carrier particles and toner powder in a predetermined desired concentration and (2) means for indicating whether the developer mix in the development station is fresh; means for producing a signal representative of the concentration of toner powder in the developer mix in the chamber; means for setting a reference signal; means for sensing the indicating means of a received development station for determining if the development mix therein is fresh; and means, operable only upon determining that the developer mix in the received development is fresh, for adjusting the reference signal until it substantially equals the toner concentration signal.
Claim 3
Dependent Claim
26 words
An electrostatographic machine as set forth in claim 1 wherein said means for adjusting the reference signal is operable only upon power-up of said electrostatographic machine.
Claim 4
Dependent Claim
15 words
An electrostatographic machine as set forth in claim 1 wherein said development station is disposable.
Claim 5
Dependent Claim
37 words
An electrostatographic machine as set forth in claim 1 further comprising means for adjusting the indicating means of a received development station upon power-up of the machine to indicate that the developer mix therein is not fresh.
Claim 6
Dependent Claim
196 words
An electrostatographic machine comprising: means for receiving replaceable development stations of the type having (1) a first chamber containing a developer mix of carrier particles and toner powder in a predetermined desired concentration, (2) a second chamber for a supply of toner powder to be delivered to the first chamber to maintain the predetermined concentration of toner powder in the developer mix, (3) feed means for delivering toner powder from the second chamber to the first chamber; and (4) means for indicating whether the developer mix in the first chamber is fresh; means for producing a signal representative of the concentration of toner powder in the developer mix in the chamber; means for setting a reference signal; means for sensing the indicating means of a received development station for determining if the development mix therein is fresh; means, operable only upon determining that the developer mix in the received development is fresh, for adjusting the reference signal until it substantially equals the toner concentration signal; and means for comparing the reference signal and the toner concentration signal and for operating the feed means when the difference between the reference and concentration signals reaches a predetermined threshold.
Claim 7
Dependent Claim
196 words
An electrostatographic machine comprising: means for receiving replaceable development stations of the type having (1) a first chamber containing a developer mix of carrier particles and toner powder in a predetermined desired concentration, (2) a second chamber for a supply of toner powder to be delivered to the first chamber to maintain the predetermined concentration of toner powder in the developer mix, (3) feed means for delivering toner powder from the second chamber to the first chamber; and (4) means for indicating whether the developer mix in the first chamber is fresh; means for producing a signal representative of the concentration of toner powder in the developer mix in the chamber; means for setting a reference signal; means for sensing the indicating means of a received development station for determining if the development mix therein is fresh; means, operable only upon determining that the developer mix in the received development is fresh, for adjusting the reference signal until it substantially equals the toner concentration signal; and means for comparing the reference signal and the toner concentration signal and for operating the feed means when the difference between the reference and concentration signals reaches a predetermined threshold.
Claim 8
Dependent Claim
26 words
An electrostatographic machine as set forth in claim 5 wherein said means for adjusting the reference signal is operable only upon power-up of said electrostatographic machine.
Claim 9
Dependent Claim
15 words
An electrostatographic machine as set forth in claim 5 wherein said development station is disposable.
Claim 10
Dependent Claim
123 words
An electrostatographic machine comprising: means for receiving replaceable development stations of the type having (1) a chamber containing a developer mix of carrier particles and toner powder in a predetermined desired concentration and (2) frangible means for indicating whether the developer mix in the development station is fresh; means for producing a signal representative of the concentration of toner powder in the developer mix in the chamber; means for setting a reference signal; means for sensing the frangible means of a received development station for determining if the development mix therein is fresh; and means, operable only upon determining that the developer mix in the received development station is fresh, for adjusting the reference signal until it substantially equals the toner concentration signal.
Claim 11
Dependent Claim
123 words
An electrostatographic machine comprising: means for receiving replaceable development stations of the type having (1) a chamber containing a developer mix of carrier particles and toner powder in a predetermined desired concentration and (2) frangible means for indicating whether the developer mix in the development station is fresh; means for producing a signal representative of the concentration of toner powder in the developer mix in the chamber; means for setting a reference signal; means for sensing the frangible means of a received development station for determining if the development mix therein is fresh; and means, operable only upon determining that the developer mix in the received development station is fresh, for adjusting the reference signal until it substantially equals the toner concentration signal.
Claim 12
Dependent Claim
26 words
An electrostatographic machine as set forth in claim 8 wherein said means for adjusting the reference signal is operable only upon power-up of said electrostatographic machine.
Claim 13
Dependent Claim
27 words
An electrostatographic machine as set forth in claim 8 further comprising means for breaking the frangible means in a received development station upon power-up of the machine.
Claim 14
Dependent Claim
111 words
An electrostatographic machine comprising: means for receiving replaceable development stations of the type having (1) a chamber containing a developer mix of carrier particles and toner powder in a predetermined desired concentration and (2) an electrical fuse; means for producing a signal representative of the concentration of toner powder in the developer mix in the chamber; means for setting a reference signal; an electrical circuit connectable to the fuse of a received development station for determining if the fuse is blown; and means, operable only upon determining that the fuse in a received development station is not blown, for adjusting the reference signal until it substantially equals the toner concentration signal.
Claim 15
Dependent Claim
111 words
An electrostatographic machine comprising: means for receiving replaceable development stations of the type having (1) a chamber containing a developer mix of carrier particles and toner powder in a predetermined desired concentration and (2) an electrical fuse; means for producing a signal representative of the concentration of toner powder in the developer mix in the chamber; means for setting a reference signal; an electrical circuit connectable to the fuse of a received development station for determining if the fuse is blown; and means, operable only upon determining that the fuse in a received development station is not blown, for adjusting the reference signal until it substantially equals the toner concentration signal.
Claim 16
Dependent Claim
26 words
An electrostatographic machine as set forth in claim 11 wherein said means for adjusting the reference signal is operable only upon power-up of said electrostatographic machine.
Claim 17
Dependent Claim
26 words
An electrostatographic machine as set forth in claim 11 further comprising means for blowing the fuse in a received development station upon power-up of the machine.
References Cited (Backward Citations)
US4155638A
Cited
US4551000A
Cited
US4607941A
Cited
US4699494A
Cited
DE3428587A1
Cited
US4674790A
Cited
US4707748A
Cited
US4708458A
Cited
US4711555A
Cited
JPS6243311A
Cited
US4671646A
Cited
US4742370A
Cited
EP0302415A2
Cited
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-09-10 | 1994-03-12 | 1994-09-11 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-09-10 | 1998-03-12 | 1998-09-11 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-09-10 | 2002-03-12 | 2002-09-11 | $7700.00 | Window Closed / Lapsed |