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US4720727A Expired / Lapsed US ⏱️ 0.0 years remaining

Image forming apparatus

Assignee: Canon Inc
•
Filing: 1987-03-09
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Granted: 1988-01-19
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Expires: 2007-03-09
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Abstract

Abstract An image forming apparatus includes a drum heater for heating an image bearing member and a guide for guiding air to the image bearing member. The guide forms a path of the air flow. In the path, there are provided a filter for removing dust from the air adjacent an optical system, a fan and a heater for heating the air. The air heated by the heater is introduced to the image bearing member after passing by or around a corona wire of a charger of the image forming apparatus so as to remove moisture from the image bearing member.

Inventors

  • 👤 Yasumi Yoshida

Bibliographic Details

Application Number —
Jurisdiction US
Data Source google_patents
Last Synchronized 2026-10-29 15:46
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/75; G03G15/751; G03G15/02; G03G15/0258; G03G15/0291; G03G21/00; G03G21/20; G03G21/203; G03G21/206

Claims Analysis

Total Claims: 34
Claim 1
Independent Claim 57 words
An image forming apparatus, comprising: an image bearing member; first heating means for heating said image bearing member; second heating means for heating air; means for guiding the air heated to said image bearing member; and means for controlling said second heating means to operate it during an initial stage of operation of said image forming apparatus.
Claim 2
Dependent Claim 57 words
An image forming apparatus, comprising: an image bearing member; first heating means for heating said image bearing member; second heating means for heating air; means for guiding the air heated to said image bearing member; and means for controlling said second heating means to operate it during an initial stage of operation of said image forming apparatus.
Claim 3
Dependent Claim 13 words
An apparatus according to claim 1, wherein said guiding means includes a fan.
Claim 4
Dependent Claim 33 words
An apparatus according to claim 2, further comprising a filter for removing dust from the air, which is disposed downstream of the fan with respect to a direction of flow of the air.
Claim 5
Dependent Claim 26 words
An apparatus according to claim 2, further comprising second heating means disposed downstream of the fan with respect to a direction of flow of the air.
Claim 6
Dependent Claim 35 words
An apparatus according to claim 1, wherein said image bearing member is maintained by said first heating means during image forming operation of said image forming apparatus at a temperature higher than a normal temperature.
Claim 7
Dependent Claim 48 words
An apparatus according to claim 5, wherein said image bearing member has a surface layer of amorphous silicon, and said second heating means is effective to heat the air to a level by which the air has a temperature of 30°-60° C. when reaching said image bearing member.
Claim 8
Dependent Claim 42 words
An apparatus according to claim 1, further comprising means for generating ions to be applied to said image bearing member, said ion generating means having an ion generating portion in a path of flow of the air to said image bearing member.
Claim 9
Dependent Claim 42 words
An apparatus according to claim 7, wherein the ion generating portion is disposed upstream of said image bearing member with respect to a direction of flow of the air, whereby the air reaches said image bearing member after the ion generating portion.
Claim 10
Dependent Claim 19 words
An apparatus according to claim 1, wherein said control means energizes said second heating means during a waiting period.
Claim 11
Dependent Claim 45 words
An apparatus according to claim 1, wherein said control means controls said second heating means so as to heat the air during an initial stage of operation of said image forming apparatus to a temperature higher than that during a stabilized period of operation thereof.
Claim 12
Dependent Claim 34 words
An apparatus according to claim 10, wherein said control means controls said second heating means to supply during the initial stage higher electric energy to said second heating means than during the stabilized period.
Claim 13
Dependent Claim 35 words
An apparatus according to claim 11, wherein said second heating means includes a plurality of heaters, and wherein number of the heaters energized is larger during the initial stage than that in the stabilized period.
Claim 14
Dependent Claim 30 words
An apparatus according to claim 11, wherein said control means controls said second heating means to energize it during the initial stage and to deenergize it during the stabilized period.
Claim 15
Dependent Claim 40 words
An apparatus according to claim 2, further commprising fan control means for controlling said fan to change a speed of the air between an initial stage of operation of said image forming apparatus and a stabilized state of operation thereof.
Claim 16
Dependent Claim 41 words
An apparatus according to claim 2, wherein said fan control means controls said fan to deliver a larger amount of the air during an initial stage of operation of said image forming apparatus than in a stabilized period of operation thereof.
Claim 17
Dependent Claim 33 words
An apparatus according to claim 14, wherein said fan control means controls rotational speed of said fan so that the rotational speed is higher in the initial stage than in the stabilized period.
Claim 18
Dependent Claim 32 words
An apparatus according to claim 1, wherein said control means operates said second heating means during an initial stage of operation of said image forming apparatus for a predetermined period of time.
Claim 19
Dependent Claim 29 words
An apparatus according to claim 1, further comprising heat fixing means for fixing an image with heat, wherein said heat fixing means functions also as said second heating means.
Claim 20
Dependent Claim 90 words
An image forming apparatus, comprising: an image bearing member; first heating means for heating said image bearing member; temperature detecting means for detecting temperature of said image bearing member; first control means for controlling said first heating means in accordance with an output of said temperature detecting means; second heating means for heating air; means for guiding the air heated by said second heating means to said image bearing member; and second control means for controlling said second heating means in accordance with the output of said temperature detecting means.
Claim 21
Dependent Claim 90 words
An image forming apparatus, comprising: an image bearing member; first heating means for heating said image bearing member; temperature detecting means for detecting temperature of said image bearing member; first control means for controlling said first heating means in accordance with an output of said temperature detecting means; second heating means for heating air; means for guiding the air heated by said second heating means to said image bearing member; and second control means for controlling said second heating means in accordance with the output of said temperature detecting means.
Claim 22
Dependent Claim 29 words
An apparatus according to claim 19, wherein said second control means controls said second heating means to energize during an initial stage of operation of said image forming apparatus.
Claim 23
Dependent Claim 65 words
An apparatus according to claim 20, wherein said first control means controls said first heating means to maintain a substantially constant temperature of said image bearing member, and wherein said second control means controls to deenergize said second heating means when the temperature of said image bearing member reaches a predetermined level, the predetermined level of the temperature is substantially equal to the constant temperature.
Claim 24
Dependent Claim 57 words
An apparatus according to claim 19, wherein said first control means controls said first heating means to maintain a substantially constant temperature of said image bearing member, and wherein said second heating means controls said second heating means so that temperature of the air introduced to said image bearing member is substantially equal to the constant temperature.
Claim 25
Dependent Claim 61 words
An apparatus according to claim 20, wherein said first control means controls said first heating means to maintain a substantially constant temperature of said image bearing member, and wherein temperature of the air introduced to said image bearing member during at least a part of an initial stage of operation of said image forming apparatus is higher than the constant temperature.
Claim 26
Dependent Claim 43 words
An image forming apparatus, comprising: an image bearing member; means for heating air; means for guiding the heated air to said image bearing member; and control means for energizing said heating means during an initial stage of operation of said image forming apparatus.
Claim 27
Dependent Claim 43 words
An image forming apparatus, comprising: an image bearing member; means for heating air; means for guiding the heated air to said image bearing member; and control means for energizing said heating means during an initial stage of operation of said image forming apparatus.
Claim 28
Dependent Claim 13 words
An apparatus according to claim 24, wherein said guiding means includes a fan.
Claim 29
Dependent Claim 18 words
An apparatus according to claim 24, wherein said image bearing member has a surface layer of amorphous silicon.
Claim 30
Dependent Claim 44 words
An apparatus according to claim 24, further comprising means for generating ions to be applied to said image bearing member, said ion generating means having ion generating portion which is disposed in a path of flow of the air to said image bearing member.
Claim 31
Dependent Claim 45 words
An apparatus according to claim 27, wherein the ion generating portion is disposed upstream of said image bearing member with respect to a direction of the flow of the air, wherein the air reaches said image bearing member after passing around the ion generating portion.
Claim 32
Dependent Claim 21 words
An apparatus according to claim 24, wherein said control means energizes said heating means during a waiting period of said apparatus.
Claim 33
Dependent Claim 44 words
An apparatus according to claim 24, further comprising optical system for projecting a light image of an original onto said image bearing member, wherein the air adjacent said optical system is introduced to said image bearing member through a filter and said heating means.
Claim 34
Dependent Claim 27 words
An apparatus according to claim 24, heat insulating material is disposed between said optical system and a guide for guiding the air to said image bearing member.

References Cited (Backward Citations)

US4319828A Cited
US4161357A Cited
US4306802A Cited
US4585319A Cited
US4571056A Cited
US4545671A Cited

USPTO Annuity & Maintenance Windows

Annuity Stage Window Opens Payment Deadline Surcharge Period Until Estimated Fee Status
3.5 Years (Year 4) 1991-01-18 1991-07-20 1992-01-19 $2000.00 Window Closed / Lapsed
7.5 Years (Year 8) 1995-01-18 1995-07-20 1996-01-19 $3760.00 Window Closed / Lapsed
11.5 Years (Year 12) 1999-01-18 1999-07-20 2000-01-19 $7700.00 Window Closed / Lapsed

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