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US4647185A Expired / Lapsed US ⏱️ 0.0 years remaining

Developer detecting device

Assignee: Canon Inc
•
Filing: 1985-02-22
•
Granted: 1987-03-03
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Expires: 2005-02-22
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Abstract

Abstract A developer detecting device includes a developing unit for developing latent images with developer, a stirring unit for stirring the developer, a detector for detecting, during a stirring period, a decrease in the amount of developer and circuitry which outputs a signal detection only after a detection by the detector for at least one stirring period.

Inventors

  • 👤 Hiroaki Takeda
  • 👤 Masato Ishida

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-25 12:57
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G15/0822; G03G15/0848; G03G15/0856; G03G15/086; G03G15/0865; G03G15/0875

Claims Analysis

Total Claims: 17
Claim 1
Independent Claim 84 words
A developer detecting device comprising: container means for containing a developer; developing means for developing latent images with developer from said container means; stirring means for periodically stirring the developer in said container means; detecting means for detecting the amount of developer in said container means a plurality of times during at least one stirring period; and decision means for deciding, in accordance with the number of detections by said detecting means, whether or not the amount of developer is below a predetermined amount.
Claim 2
Dependent Claim 84 words
A developer detecting device comprising: container means for containing a developer; developing means for developing latent images with developer from said container means; stirring means for periodically stirring the developer in said container means; detecting means for detecting the amount of developer in said container means a plurality of times during at least one stirring period; and decision means for deciding, in accordance with the number of detections by said detecting means, whether or not the amount of developer is below a predetermined amount.
Claim 3
Dependent Claim 41 words
A developer detecting device according to claim 1, wherein when all of the plurality of detections show that the amount of the developer is less than the predetermined amount, the decision means decides that the developer is below the predetermined amount.
Claim 4
Dependent Claim 14 words
A developer detecting device according to claim 1, wherein the developer is a toner.
Claim 5
Dependent Claim 18 words
A developer detecting device according to claim 1 further comprising means for displaying the amount of the developer.
Claim 6
Dependent Claim 169 words
A recording apparatus comprising: container means for recording with a recording agent; means for containing the recording agent; and means for detecting and outputting a signal indicating the condition of the recording agent in said container means, wherein the criterion for outputting a signal indicating a decrease in the amount of the recording agent is different from the criterion for outputting a signal indicating a recovery in the amount of the recording agent, wherein the decrease criterion is that the amount of the recording agent is detected a plurality of times during a first predetermined time period and all of the plurality of detections shows a reduction in the amount of the recording agent to a level less than a predetermined level and the recovery criterion is that the amount of the recording agent is detected a plurality of times during a second predetermined time period and all of the plurality of detections show recovery in the amount of the recording agent to a level above the predetermined level.
Claim 7
Dependent Claim 169 words
A recording apparatus comprising: container means for recording with a recording agent; means for containing the recording agent; and means for detecting and outputting a signal indicating the condition of the recording agent in said container means, wherein the criterion for outputting a signal indicating a decrease in the amount of the recording agent is different from the criterion for outputting a signal indicating a recovery in the amount of the recording agent, wherein the decrease criterion is that the amount of the recording agent is detected a plurality of times during a first predetermined time period and all of the plurality of detections shows a reduction in the amount of the recording agent to a level less than a predetermined level and the recovery criterion is that the amount of the recording agent is detected a plurality of times during a second predetermined time period and all of the plurality of detections show recovery in the amount of the recording agent to a level above the predetermined level.
Claim 8
Dependent Claim 19 words
A recording apparatus according to claim 5, wherein the first time period is longer than the second time period.
Claim 9
Dependent Claim 13 words
A recording apparatus according to claim 6, wherein the recording agent is developer.
Claim 10
Dependent Claim 26 words
A recording apparatus according to claim 7, further comprising means for periodically stirring the recording agent at a predetermined period shorter than the first time period.
Claim 11
Dependent Claim 101 words
A recording apparatus comprising: means for recording with a recording agent; container means for containing the recording agent; means for detecting the amount of the recording agent in said container means a plurality of times during at least one stirring period; and means for outputting a signal indicating the condition of the recording agent in accordance with the number of detections by said detecting means, wherein the criterion for outputting a signal indicating a decrease in the amount of the recording agent is different from the criterion for outputting a signal indicating a recovery in the amount of the recording agent.
Claim 12
Dependent Claim 101 words
A recording apparatus comprising: means for recording with a recording agent; container means for containing the recording agent; means for detecting the amount of the recording agent in said container means a plurality of times during at least one stirring period; and means for outputting a signal indicating the condition of the recording agent in accordance with the number of detections by said detecting means, wherein the criterion for outputting a signal indicating a decrease in the amount of the recording agent is different from the criterion for outputting a signal indicating a recovery in the amount of the recording agent.
Claim 13
Dependent Claim 19 words
A recording apparatus according to claim 9, wherein the recovery criterion is easier to satisfy than the decrease criterion.
Claim 14
Dependent Claim 103 words
A recording apparatus according to claim 9, wherein the decrease criterion is that the amount of the recording agent is detected a plurality of times during a first predetermined time period and all of the plurality of detections show a reduction in the amount of the recording agent to a level less than a predetermined level and the recovery criterion is that the amount of the recording agent is detected a plurality of times during a second predetermined time period and all of the plurality of detections show recovery in the amount of the recording agent to a level above the predetermined level.
Claim 15
Dependent Claim 19 words
A recording apparatus according to claim 11, wherein the first time period is longer than the second time period.
Claim 16
Dependent Claim 13 words
A recording apparatus according to claim 12, wherein the recording agent is developer.
Claim 17
Dependent Claim 26 words
A recording apparatus according to claim 13, further comprising means for periodically stirring the recording agent at a predetermined period shorter than the first time period.

References Cited (Backward Citations)

US4200665A Cited
US4226525A Cited
US4240375A Cited
US4270487A Cited
US4241696A Cited
US4338019A Cited
US4332467A Cited
US4405226A Cited
US4423948A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1990-03-02 1990-09-01 1991-03-03 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1994-03-02 1994-09-01 1995-03-03 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1998-03-02 1998-09-01 1999-03-03 $7700.00 Window Closed / Lapsed

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