EP0281372A1
Expired / Lapsed
EP
⏱️ 0.0 years remaining
Device for detecting life of image forming process unit, opening of seal of the unit and attachement of the unit to an image forming apparatus
Assignee: Kyocera Mita Industrial Co Ltd
•
Filing: 1988-03-02
•
Granted: —
•
Expires: 2008-03-02
Abstract
Abstract A device is provided for detecting the life expiry of a process unit detachably attached to an image forming apparatus for detecting the initial opening of a seal of the unit and for detecting attachment of the unit to the image forming apparatus. The device judges when the process unit has reached its life expiry by comparing the output of a sensor (65) for detecting the density of toner contained in the developing device with a predetermined value and detecting when the output of the sensor is above the predetermined value. When the process unit has a developer storage section defined by a seal member (63) for containing developer in the developing device, the seal member is normally opened whens the developing device is installed, so that developer is supplied into a developer chamber having a developing roller. The detecting device judges that the seal (63) is unopened when the output of the sensor (65) is not the output level of the normal use state. Thirdly, when attaching the process unit to the apparatus, the output terminal of the sensor (65) on the developing device and the input terminal of control means provided in the apparatus are connected with each other, so that the control means can judge that the process unit is not attached when the voltage of the input terminal of the control means is not the voltage level of the normal use state.
Inventors
- 👤 Tomio Tada
- 👤 Junichi Hirobe
- 👤 Junichi Takamatsu
- 👤 Kazuto Hori
Bibliographic Details
Application Number
—
Jurisdiction
EP
Data Source
google_patents
Last Synchronized
2026-11-06 01:46
CPC Classifications
G; G03; G03G; G03G21/00; G03G21/16; G03G21/18; G03G21/1875; G03G21/1878; G03G21/1882; G03G21/1885; G03G15/00; G03G15/06; G03G15/08; G03G15/0822; G03G15/0848; G03G15/0849; G03G15/0853; G03G15/0856; G03G15/0877; G03G15/0881; G03G15/0882; G03G21/1642; G03G21/1647; G03G21/1652; G03G21/1892; G03G2221/00; G03G2221/16; G03G2221/163; G03G2221/1648; G03G2221/1651; G03G2221/1657; G03G2221/166; G03G2221/1663; G03G2221/18; G03G2221/183; G03G2221/1892
Claims Analysis
Total Claims: 14
Claim 1
Independent Claim
154 words
A device for detecting life of a process unit detachably attached to an image forming apparatus and having at least a developing device in a casing comprising: a sensor for detecting the density of toner contained in the developing device; means for detecting whether the output of the sensor is above a predetermined value after a developing roller of the developing device starts rotating and before a predetermined time lapses; and control means for changing operation to a usual image forming operation when the output of the sensor is below a predetermined value, and judging that the process unit has reached the end of its working life when the output of the sensor is above the predetermined value at the time that the predetermined time lapses with the output of the sensor not coming to a value lower than the predetermined value and issuing a signal concerning the life of the process unit accordingly.
Claim 2
Independent Claim
154 words
A device for detecting life of a process unit detachably attached to an image forming apparatus and having at least a developing device in a casing comprising: a sensor for detecting the density of toner contained in the developing device; means for detecting whether the output of the sensor is above a predetermined value after a developing roller of the developing device starts rotating and before a predetermined time lapses; and control means for changing operation to a usual image forming operation when the output of the sensor is below a predetermined value, and judging that the process unit has reached the end of its working life when the output of the sensor is above the predetermined value at the time that the predetermined time lapses with the output of the sensor not coming to a value lower than the predetermined value and issuing a signal concerning the life of the process unit accordingly.
Claim 3
Dependent Claim
46 words
A device for detecting life of a process unit as defined in claim 1 wherein the predetermined time is a time required for stabilizing the fixing device after a time required for stabilizing the output of the sensor lapses after a power source is switched on.
Claim 4
Dependent Claim
62 words
A device for detecting life of a process unit as defined in claim 1 wherein after a print key is turned on, the predetermined time is a delayed time provided after any one of steps of turning on the print key, starting of the first paper feeding, starting of the rotation of the developing roller and end of the first paper feeding.
Claim 5
Dependent Claim
27 words
A device for detecting life of a process unit as defined in claim 3 wherein the predetermined time includes a time required for the first paper feeding.
Claim 6
Dependent Claim
38 words
A device for detecting life of a process unit as defined in claim 3 wherein the predetermined time includes a time required for the first paper feeding and a delayed time for starting of the second paper feeding.
Claim 7
Dependent Claim
33 words
A device for detecting life of a process unit as defined in claim 5 wherein the delayed time for the second paper feeding is started at the end of the first paper feeding.
Claim 8
Independent Claim
54 words
A device for detecting life of the process unit as defined in any one of claims 1 to 6 wherein after the operation is changed to the image forming operation, the control means judges that the process unit has reached its life end when the output of the sensor is above the predetermined value.
Claim 9
Independent Claim
137 words
A device for detecting opening of seal of a process unit attachable to an image forming apparatus and having at least a developing device in a casing, the developing device having a developer storage section defined by a seal member for containing developer, whereby normally when the unit is attached to an image forming apparatus the seal member is opened so that developer is supplied into a developer chamber having a developing roller, the detecting device comprising: a sensor located adjacent the developing device for detecting presence of developer or the density of toner contained in a developer chamber; and control means for judging that the seal member is unopened when the output of the sensor is not a predetermined value corresponding to the normal use state and issuing a signal indicating non-opening of the seal accordingly.
Claim 10
Independent Claim
137 words
A device for detecting opening of seal of a process unit attachable to an image forming apparatus and having at least a developing device in a casing, the developing device having a developer storage section defined by a seal member for containing developer, whereby normally when the unit is attached to an image forming apparatus the seal member is opened so that developer is supplied into a developer chamber having a developing roller, the detecting device comprising: a sensor located adjacent the developing device for detecting presence of developer or the density of toner contained in a developer chamber; and control means for judging that the seal member is unopened when the output of the sensor is not a predetermined value corresponding to the normal use state and issuing a signal indicating non-opening of the seal accordingly.
Claim 11
Dependent Claim
43 words
A device for detecting opening of seal of a process unit as defined in claim 8 wherein the detection of whether the seal member is opened is executed after a print key is turned on and before the first paper feeding is started.
Claim 12
Independent Claim
138 words
A device for detecting attachment of a process unit attachable to an image forming apparatus and having at least a developing device in a casing, comprising: a sensor for detecting presence of developer or the density of toner contained in the developing device and having an output terminal for issuing signals; and control means provided in the apparatus and having an input terminal for receiving a signal from the sensor; the output terminal of the sensor and the input terminal of the control means being connected to each other by attaching the process unit to the apparatus; and the control means judging that the process unit is unattached when the voltage of the input terminal thereof is not the value corresponding to the normal use state and issuing a signal indicating the non-attachment of the process unit accordingly.
Claim 13
Independent Claim
138 words
A device for detecting attachment of a process unit attachable to an image forming apparatus and having at least a developing device in a casing, comprising: a sensor for detecting presence of developer or the density of toner contained in the developing device and having an output terminal for issuing signals; and control means provided in the apparatus and having an input terminal for receiving a signal from the sensor; the output terminal of the sensor and the input terminal of the control means being connected to each other by attaching the process unit to the apparatus; and the control means judging that the process unit is unattached when the voltage of the input terminal thereof is not the value corresponding to the normal use state and issuing a signal indicating the non-attachment of the process unit accordingly.
Claim 14
Dependent Claim
16 words
An image forming apparatus having a device according to any one of claims 1 to 10.
References Cited (Backward Citations)
US4538896A
Cited
USPTO Annuity & Maintenance Windows
Maintenance schedule is calculated for granted US utility patents.