Patent US5995751A successfully refreshed from Google Patents.
Patent US5095331A successfully refreshed from Google Patents.
US5095331A
Expired / Lapsed
US
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Image forming apparatus having toner-empty detecting and indicating mechanism
Assignee: Toshiba Corp
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Filing: 1989-10-25
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Granted: 1992-03-10
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Expires: 2009-10-25
Abstract
Abstract The density of a toner in a developing device is detected by a magnetic sensor if the density is lower than a reference value, a toner-empty state is indicated on a control panel. When a copy key is operated in this toner-empty state, the number of copies in the toner-empty state is counted by means of a counter. If the count value is not larger than a preset value, the copying operation is allowed. If the count value exceeds the predetermined value, the copying operation is prohibited.
Inventors
- 👤 Shouji Takano
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-09 15:07
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G15/0822; G03G15/0848; G03G15/0849; G03G15/0853
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
91 words
An image forming apparatus comprising: means for developing an original image on an image carrier to form an image thereon with a toner; means for detecting the density of the toner; means for displaying a toner-empty status when the toner density detected by the detecting means is lower than a predetermined value; means for counting the cycles of image forming operation when the toner-empty status is displayed by the displaying means; and means for performing the image forming operation before the count value in the counting means attains a predetermined value.
Claim 2
Dependent Claim
91 words
An image forming apparatus comprising: means for developing an original image on an image carrier to form an image thereon with a toner; means for detecting the density of the toner; means for displaying a toner-empty status when the toner density detected by the detecting means is lower than a predetermined value; means for counting the cycles of image forming operation when the toner-empty status is displayed by the displaying means; and means for performing the image forming operation before the count value in the counting means attains a predetermined value.
Claim 3
Dependent Claim
20 words
An apparatus according to claim 1, wherein the developing means contains a developing agent having a toner and a carrier.
Claim 4
Dependent Claim
17 words
An apparatus according to claim 1, further comprising means for supplying the toner to the developing means.
Claim 5
Dependent Claim
26 words
An apparatus according to claim 3, further comprising means for driving the supply means in response to the result of the detection by the detecting means.
Claim 6
Dependent Claim
40 words
An apparatus according to claim 4, further comprising means for identifying a toner-empty state when the toner density detected by the detecting means is lower than the predetermined value after the drive means is driven a preset number of times.
Claim 7
Dependent Claim
14 words
An apparatus according to claim 5, wherein said detecting means includes a magnetic sensor.
Claim 8
Dependent Claim
74 words
An apparatus according to claim 8, wherein said magnetic sensor includes means for generating a highfrequency signal, transformer means supplied with the high-frequency signal produced by the generating means, means for supplying a reference signal to the transformer means, means for comparing the phase of an electromotive force corresponding to the toner density, delivered from the transformer means, with that of the high-frequency signal, and means for integrating the output of the comparing means.
Claim 9
Independent Claim
91 words
An apparatus for determining the density of a toner comprising: means for supplying the toner to the developing means; means for detecting the density of the toner; means for driving the supplying means in response to the result of the detection by the detecting means; means for identifying a toner-empty status when the toner density detected by the detecting means is lower than a predetermined value after the drive means is driven a preset number of times; and means for displaying information showing the toner-empty status identified by the identifying means.
Claim 10
Independent Claim
91 words
An apparatus for determining the density of a toner comprising: means for supplying the toner to the developing means; means for detecting the density of the toner; means for driving the supplying means in response to the result of the detection by the detecting means; means for identifying a toner-empty status when the toner density detected by the detecting means is lower than a predetermined value after the drive means is driven a preset number of times; and means for displaying information showing the toner-empty status identified by the identifying means.
Claim 11
Dependent Claim
20 words
An apparatus according to claim 8, wherein the developing means contains a developing agent having a toner and a carrier.
Claim 12
Dependent Claim
14 words
An apparatus according to claim 8, wherein said detecting means includes a magnetic sensor.
Claim 13
Dependent Claim
74 words
An apparatus according to claim 10, wherein said magnetic sensor includes means for generating a high-frequency signal, transformer means supplied with the high-frequency signal produced by the generating means, means for supplying a reference signal to the transformer means, means for comparing the phase of an electromotive force corresponding to the toner density, delivered from the transformer means, with that of the high-frequency signal, and means for integrating the output of the comparing means.
Claim 14
Dependent Claim
26 words
An apparatus according to claim 8, further comprising means for indicating information of the toner-empty state if the toner-empty state is identified by the identifying means.
Claim 15
Dependent Claim
28 words
An apparatus according to claim 8, further comprising means for setting a flag indicative of the toner-empty state if the toner-empty state is identified by the identifying means.
Claim 16
Dependent Claim
53 words
An image forming method comprising: detecting the density of a toner; displaying a toner-empty status when the detected toner density is lower than a predetermined value; counting the cycles of image forming operation when the toner-empty status is displayed; and performing the image forming operation before the count value attains a predetermined value.
Claim 17
Dependent Claim
53 words
An image forming method comprising: detecting the density of a toner; displaying a toner-empty status when the detected toner density is lower than a predetermined value; counting the cycles of image forming operation when the toner-empty status is displayed; and performing the image forming operation before the count value attains a predetermined value.
Claim 18
Dependent Claim
90 words
A magnetic sensor for detecting the density of toner in an image forming apparatus, comprising: means for generating a high-frequency signal; transformer means for receiving the high-frequency signal produced by the generating means; means for supplying a reference signal to the transformer means; means for comparing the phase of an electromotive force corresponding to the toner density, delivered from the transformer means, with the phase of the high-frequency signal; and means for integrating the output of the comparing means, the integrated output indicating if a toner-empty state has been reached.
Claim 19
Dependent Claim
90 words
A magnetic sensor for detecting the density of toner in an image forming apparatus, comprising: means for generating a high-frequency signal; transformer means for receiving the high-frequency signal produced by the generating means; means for supplying a reference signal to the transformer means; means for comparing the phase of an electromotive force corresponding to the toner density, delivered from the transformer means, with the phase of the high-frequency signal; and means for integrating the output of the comparing means, the integrated output indicating if a toner-empty state has been reached.
Claim 20
Dependent Claim
27 words
The magnetic sensor of claim 15 further including means for driving the image forming apparatus a preset number of times following the indication of the toner-empty state.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1995-03-10 | 1995-09-09 | 1996-03-10 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1999-03-10 | 1999-09-09 | 2000-03-10 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2003-03-10 | 2003-09-09 | 2004-03-10 | $7700.00 | Window Closed / Lapsed |