US5475476A
Expired / Lapsed
US
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Image density control method for an image recorder
Assignee: Ricoh Co Ltd
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Filing: 1993-08-13
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Granted: 1995-12-12
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Expires: 2013-08-13
Abstract
Abstract An image density control method applicable to an electrophotographic copier or similar image recorder for controlling the toner concentration of a two-component developer, i.e., a mixture of toner and carrier to maintain the density of a toner image produced by the developer constant. Predetermined calculations are performed on the basis of the output of a photosensor which is responsive to the toner images representative of reference patterns formed on a photoconductive element.
Inventors
- 👤 Kazuo Murai
- 👤 Shinji Kato
- 👤 Hisao Murayama
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-29 22:59
CPC Classifications
G; G03; G03G; G03G15/00; G03G15/06; G03G15/08; G03G15/0822; G03G15/0848; G03G15/0849; G03G15/0853; G03G15/50; G03G15/5033; G03G15/5041; G03G2215/00; G03G2215/00025; G03G2215/00118
Claims Analysis
Total Claims: 20
Claim 1
Independent Claim
134 words
An image density control method for controlling a density of a toner image formed on a photoconductive element by a developing unit, said method comprising the steps of: totally estimating a developing ability of said developing unit in response to a plurality of data including an operation time of said developing unit, a toner concentration, an amount of toner consumption, an amount of toner supply, a remaining amount of toner to be supplied, a reflection density ratio of a toner image of a reference pattern sensed by a photosensor, a temperature and a humidity around said developing unit, and at least one of history data thereof; and selectively controlling at least one of a latent image forming condition, a toner supply condition, a member for charging a developer, and a bias condition for development.
Claim 2
Dependent Claim
134 words
An image density control method for controlling a density of a toner image formed on a photoconductive element by a developing unit, said method comprising the steps of: totally estimating a developing ability of said developing unit in response to a plurality of data including an operation time of said developing unit, a toner concentration, an amount of toner consumption, an amount of toner supply, a remaining amount of toner to be supplied, a reflection density ratio of a toner image of a reference pattern sensed by a photosensor, a temperature and a humidity around said developing unit, and at least one of history data thereof; and selectively controlling at least one of a latent image forming condition, a toner supply condition, a member for charging a developer, and a bias condition for development.
Claim 3
Dependent Claim
26 words
A method as claimed in claim 1, wherein said history data for computing the amount of toner supply comprises history data per unit image forming signal.
Claim 4
Dependent Claim
46 words
A method as claimed in claim 2, wherein at least two counters are used to add up image forming signals, at least one of said at least two counters starting counting, stopping counting, and resetting a count at timings different from timings of the other counter.
Claim 5
Dependent Claim
81 words
An image density control method for controlling a density of a toner image formed on a photoconductive element, said method comprising the steps of: estimating an amount of toner supply required to maintain a desired image density in response to a reflection density ratio of a toner image of a reference pattern sensed by a photosensor, and history data thereof; and controlling an amount of toner supply, via fuzzy inference and control, on the basis of a result of the estimation.
Claim 6
Dependent Claim
81 words
An image density control method for controlling a density of a toner image formed on a photoconductive element, said method comprising the steps of: estimating an amount of toner supply required to maintain a desired image density in response to a reflection density ratio of a toner image of a reference pattern sensed by a photosensor, and history data thereof; and controlling an amount of toner supply, via fuzzy inference and control, on the basis of a result of the estimation.
Claim 7
Dependent Claim
83 words
An image density control method for controlling a density of a toner image formed on a photoconductive element by a developing unit, said method comprising the steps of: estimating an amount of toner supply required to maintain a desired image density in response to a toner concentration, a difference between said toner concentration and a target toner concentration, and history data thereof; and controlling an amount of toner supply, via fuzzy inference and control, on the basis of a result of the estimation.
Claim 8
Dependent Claim
83 words
An image density control method for controlling a density of a toner image formed on a photoconductive element by a developing unit, said method comprising the steps of: estimating an amount of toner supply required to maintain a desired image density in response to a toner concentration, a difference between said toner concentration and a target toner concentration, and history data thereof; and controlling an amount of toner supply, via fuzzy inference and control, on the basis of a result of the estimation.
Claim 9
Dependent Claim
45 words
A method as claimed in claim 5, wherein said target toner concentration is totally estimated on the basis of a reflection density ratio of a toner image of a reference pattern sensed by a photosensor and history data thereof, and is then set or changed.
Claim 10
Dependent Claim
28 words
A method as claimed in claim 5, wherein said target toner concentration is totally estimated on the basis of information entered by an operator, and history data thereof.
Claim 11
Dependent Claim
116 words
An image density control method for controlling a density of a toner image formed on a photoconductive element by a developing unit, said method comprising the steps of: estimating an amount of toner supply required to maintain a desired image density in response to a toner concentration, a difference between said toner concentration and a target toner concentration, and history data thereof; and controlling an amount of toner supply on the basis of a result of the estimation, wherein said target toner concentration is totally estimated on the basis of a temperature and a humidity around said developing unit, a drive time of said developing unit, and history data thereof, and is then set or changed.
Claim 12
Dependent Claim
116 words
An image density control method for controlling a density of a toner image formed on a photoconductive element by a developing unit, said method comprising the steps of: estimating an amount of toner supply required to maintain a desired image density in response to a toner concentration, a difference between said toner concentration and a target toner concentration, and history data thereof; and controlling an amount of toner supply on the basis of a result of the estimation, wherein said target toner concentration is totally estimated on the basis of a temperature and a humidity around said developing unit, a drive time of said developing unit, and history data thereof, and is then set or changed.
Claim 13
Dependent Claim
95 words
An image density control method for controlling a density of a toner image formed on a photoconductive element, said method comprising the steps of: adding up signals representing an amount of toner to be supplied in response to an image forming signal, while producing a count; supplying the toner in an amount corresponding to said count; estimating at least a bias condition for development and an image forming condition on the basis of a total count of said signals; and selectively controlling a plurality of objects on the basis of a result of the estimation.
Claim 14
Dependent Claim
95 words
An image density control method for controlling a density of a toner image formed on a photoconductive element, said method comprising the steps of: adding up signals representing an amount of toner to be supplied in response to an image forming signal, while producing a count; supplying the toner in an amount corresponding to said count; estimating at least a bias condition for development and an image forming condition on the basis of a total count of said signals; and selectively controlling a plurality of objects on the basis of a result of the estimation.
Claim 15
Dependent Claim
105 words
An image density control method for controlling a density of a toner image formed on a photoconductive element, comprising the steps of: estimating an amount of toner supply required to maintain a desired image density in response to a toner concentration, a difference between said toner concentration and a target toner concentration, and history data thereof; controlling toner supply, via fuzzy inference and control, on the basis of a result of the estimation; and estimating a desired toner concentration from a reflection density ratio of a toner image of a reference pattern sensed by a photosensor, and history data thereof per unit image forming signal.
Claim 16
Dependent Claim
105 words
An image density control method for controlling a density of a toner image formed on a photoconductive element, comprising the steps of: estimating an amount of toner supply required to maintain a desired image density in response to a toner concentration, a difference between said toner concentration and a target toner concentration, and history data thereof; controlling toner supply, via fuzzy inference and control, on the basis of a result of the estimation; and estimating a desired toner concentration from a reflection density ratio of a toner image of a reference pattern sensed by a photosensor, and history data thereof per unit image forming signal.
Claim 17
Dependent Claim
109 words
An image density control method for controlling a density of a toner image formed on a photoconductive element by a developing unit, said method comprising the steps of: estimating a developing ability of said developing unit in terms of a combination of membership functions associated with causes which affect said developing ability including a stress acting on a developer, environmental conditions, and a change in toner concentration; and selectively controlling either of a toner supply condition and a bias condition for development on the basis of a result of the estimation, wherein said toner supply condition and said bias condition are each controlled at a particular period of time.
Claim 18
Dependent Claim
109 words
An image density control method for controlling a density of a toner image formed on a photoconductive element by a developing unit, said method comprising the steps of: estimating a developing ability of said developing unit in terms of a combination of membership functions associated with causes which affect said developing ability including a stress acting on a developer, environmental conditions, and a change in toner concentration; and selectively controlling either of a toner supply condition and a bias condition for development on the basis of a result of the estimation, wherein said toner supply condition and said bias condition are each controlled at a particular period of time.
Claim 19
Dependent Claim
120 words
An image density control method for controlling a density of a toner image formed on a photoconductive element by a developing unit, said method comprising the steps of: estimating a developing ability of said developing unit in terms of a combination of membership functions associated with causes which affect said developing ability including a stress acting on a developer, environmental conditions, and a change in toner concentration; and selectively controlling either of a toner supply condition and a bias condition for development on the basis of a result of the estimation, wherein a scale of said membership functions is changed on the basis of a result of detection of a toner image of a reference pattern by said photoconductive element.
Claim 20
Dependent Claim
120 words
An image density control method for controlling a density of a toner image formed on a photoconductive element by a developing unit, said method comprising the steps of: estimating a developing ability of said developing unit in terms of a combination of membership functions associated with causes which affect said developing ability including a stress acting on a developer, environmental conditions, and a change in toner concentration; and selectively controlling either of a toner supply condition and a bias condition for development on the basis of a result of the estimation, wherein a scale of said membership functions is changed on the basis of a result of detection of a toner image of a reference pattern by said photoconductive element.
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