US4682875A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Image forming system having external signal generating means
Assignee: Canon Inc
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Filing: 1985-12-30
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Granted: 1987-07-28
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Expires: 2005-12-30
Abstract
Abstract An image forming system comprises an image forming apparatus, a plurality of signal generators for issuing inquiry signals to the image forming apparatus, and a device for receiving the inquiry signal from the signal generator and transmitting a signal indicating a state of the image forming apparatus to the inquiring signal generator.
Inventors
- 👤 Tadashi Suzuki
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-07 02:03
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/55; G03G15/50; G03G15/5075; G03G15/5079; G03G15/553; G03G2215/00; G03G2215/00025; G03G2215/00122
Claims Analysis
Total Claims: 5
Claim 1
Independent Claim
156 words
An image forming system comprising: an image forming apparatus; a plurality of signal generating devices for generating respective inquire signals to said image forming apparatus, while said apparatus is supplied with power, wherein the respective inquire signals are for inquiring as to the states of said apparatus; means for receiving the respective inquiry signals from each of said plurality of signal generating devices; means for recognizing which one of said signal generating devices has generated a respective inquiry signal received by said receiving means; and means for transmitting an answer signal, responsive to the respective inquiry signal received by said receiving means, to said one of said signal generating devices recognized by said recognizing means, the answer signal indicating the states of said apparatus, wherein each of said signal generating devices includes means for receiving an answer signal and means for informing an operator of the states of said apparatus in response to the answer signal.
Claim 2
Dependent Claim
156 words
An image forming system comprising: an image forming apparatus; a plurality of signal generating devices for generating respective inquire signals to said image forming apparatus, while said apparatus is supplied with power, wherein the respective inquire signals are for inquiring as to the states of said apparatus; means for receiving the respective inquiry signals from each of said plurality of signal generating devices; means for recognizing which one of said signal generating devices has generated a respective inquiry signal received by said receiving means; and means for transmitting an answer signal, responsive to the respective inquiry signal received by said receiving means, to said one of said signal generating devices recognized by said recognizing means, the answer signal indicating the states of said apparatus, wherein each of said signal generating devices includes means for receiving an answer signal and means for informing an operator of the states of said apparatus in response to the answer signal.
Claim 3
Dependent Claim
22 words
An image forming system according to claim 1, wherein said plurality of signal generating means generate respective inquiry signals having respective frequencies.
Claim 4
Dependent Claim
24 words
An image forming system according to claim 2, wherein said recognizing means detects the frequency of the inquiry signal received by said receiving means.
Claim 5
Dependent Claim
28 words
An image forming system according to claim 1, wherein said transmitting means varies the frequency of the answer signal in response to an output from said recognizing means.
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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) | 1990-07-27 | 1991-01-26 | 1991-07-28 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1994-07-27 | 1995-01-26 | 1995-07-28 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1998-07-27 | 1999-01-26 | 1999-07-28 | $7700.00 | Window Closed / Lapsed |