Image forming apparatus and developer aging method
AssigneeRicoh Company, Ltd.
InventorShinji Kato
Life of this patent
Estimating the term…
Abstract
An image forming apparatus and a method of aging a developer stored in the apparatus are disclosed. The developer is adequately aged in accordance with the initial characteristic of the developer and environmental conditions. As a result, the developer automatically achieves a desired developing characteristic in a short period of time. An image of high quality, i.e., free from background contamination and local omission can be stably produced even just after the aging. In addition, toner is prevented from flying about. Even erroneous sensing by an optical sensor can be obviated.
Claims113
An image forming apparatus for forming a toner image on a photoconductive element with charging means, exposing means and developing means, and transferring said toner image to a recording medium, said apparatus comprising:
- calculating means for calculating a state amount relating to a developing characteristic of said developing means acting on said image carrier;
- aging executing means for executing at least one of agitation of a developer stored in said developing means, replenishment of toner to said developing means and consumption of toner by said developing means;
- control means for controlling said aging executing means such that said state amount calculated by said calculating means coincides with a desired state amount;
- toner density measuring means for measuring an amount of toner existing on a toner pattern produced by developing a reference latent image pattern;
- and
- an aging mode for measuring a toner density on said image carrier, for calculating a characteristic value of said developer on a basis of the measured toner density, and for effecting aging to control said state amount to said desired state amount to thereby age said developer.
An image forming apparatus for forming a toner image on a photoconductive element with charging means, exposing means and developing means, and transferring said toner image to a recording medium, said apparatus comprising:
- calculating means for calculating a state amount relating to a developing characteristic of said developing means acting on said image carrier;
- aging executing means for executing at least one of agitation of a developer stored in said developing means, replenishment of toner to said developing means and consumption of toner by said developing means;
- control means for controlling said aging executing means such that said state amount calculated by said calculating means coincides with a desired state amount;
- environment sensing means for sensing an environment when said calculating means calculates said state amount;
- and
- image forming condition varying means for varying an image forming condition assigned to usual image formation at a desired timing such that a desired image is produced;
- wherein said image forming condition varying means calculates, after aging of the developer, an image forming condition for usual image formation, controls a potential in order to set up said image forming condition, and uses a resulting controlled potential for subsequent image formation.
An image forming apparatus for forming a toner image on a photoconductive element with charging means, exposing means and developing means, and transferring said toner image to a recording medium, said apparatus comprising:
- calculating means for calculating a state amount relating to a developing characteristic of said developing means acting on said image carrier;
- aging executing means for executing at least one of agitation of a developer stored in said developing means, replenishment of toner to said developing means and consumption of toner by said developing means;
- and
- control means for controlling said aging executing means such that said state amount calculated by said calculating means coincides with a desired state amount;
- wherein said state amount relating to the developing characteristic comprises a maximum amount of toner deposition implementing image formation, said control means driving said aging executing means until said maximum amount lies in a range above an amount implementing a target image.
An image forming apparatus for forming a toner image on a photoconductive element with charging means, exposing means and developing means, and transferring said toner image to a recording medium, said apparatus comprising:
- calculating means for calculating a state amount relating to a developing characteristic of said developing means acting on said image carrier;
- aging executing means for executing at least one of agitation of a developer stored in said developing means, replenishment of toner to said developing means and consumption of toner by said developing means;
- and
- control means for controlling said aging executing means such that said state amount calculated by said calculating means coincides with a desired state amount;
- wherein said state amount relating to the developing characteristic comprises development .gamma. derived from a plurality of reference patterns, said control means driving said aging executing means until said development .gamma. lies in a preselected range of target development .gamma..
An image forming apparatus for forming a toner image on a photoconductive element with charging means, exposing means and developing means, and transferring said toner image to a recording medium, said apparatus comprising:
- calculating means for calculating a state amount relating to a developing characteristic of said developing means acting on said image carrier;
- aging executing means for executing at least one of agitation of a developer stored in said developing means replenishment of toner to said developing means and consumption of toner by said developing means;
- and
- control means for controlling said aging executing means such that said state amount calculated by said calculating means coincides with a desired state amount;
- wherein said state amount relating to the developing characteristic comprises a development start voltage derived from a plurality of reference patterns, said control means driving said aging executing means such that said development start voltage lies in a preselected range of a target development start voltage.
An image forming apparatus for forming a toner image on a photoconductive element with charging means exposing means and developing means, and transferring said toner image to a recording medium, said apparatus comprising:
- calculating means for calculating a state amount relating to a developing characteristic of said developing means acting on said image carrier;
- aging executing means for executing at least one of agitation of a developer stored in said developing means, replenishment of toner to said developing means and consumption of toner by said developing means;
- control means for controlling said aging executing means such that said state amount calculated by said calculating means coincides with a desired state amount;
- and
- image forming condition varying means for varying an image forming condition assigned to usual image formation at a desired timing such that a desired image is produced:
- wherein said image forming condition varying means calculates, after aging of the developer, an image forming condition for usual image formation, controls a potential in order to set up said image forming condition, and uses a resulting controlled potential for subsequent image formation.
An image forming apparatus including developing means, comprising:
- surface potential measuring means for measuring a surface potential of a reference latent image pattern formed on an image carrier;
- toner deposition measuring means for measuring an amount of toner existing on a toner pattern produced by developing said reference latent image pattern;
- calculating means for calculating a state amount relating to a developing characteristic on the basis of said surface potential and said amount of toner;
- aging executing means for executing at least one of agitation of a developer stored in said developing means, replenishment of toner to said developing means and toner consumption by said developing means in an interruptible manner;
- and
- control means for controlling said aging executing means such that said state amount calculated coincides with a desired state amount.
An automatic developer aging method for an image forming apparatus, comprising the steps of:
- forming a reference latent image pattern on an image carrier, and measuring a surface potential of said reference latent image pattern;
- developing said reference latent image pattern by toner, and measuring an amount of the toner deposited on said reference latent image pattern;
- calculating, based on said surface potential and said amount of toner, an instantaneous state amount relating to a developing characteristic;
- and
- executing aging of a developer on the basis of said state amount such that a desired developing characteristic is set up.
An image forming apparatus including developing means, comprising:
- surface potential measuring means for measuring a surface potential of a reference latent image pattern formed on an image carrier;
- toner deposition measuring means for measuring an amount of toner existing on a toner pattern produced by developing said reference latent image pattern;
- calculating means for calculating a state amount relating to a developing characteristic on the basis of said surface potential and said amount of toner;
- aging executing means for executing at least one of agitation of a developer stored in said developing means, replenishment of toner to said developing means and toner consumption by said developing means;
- and
- control means for controlling said aging executing means such that said state amount calculated coincides with a desired state amount.
An image forming apparatus comprising:
- forming means for forming a reference latent image on an image carrier, and measuring a surface potential of said reference image pattern;
- developing means for developing said reference latent image pattern by toner, and measuring an amount of the toner deposited on said reference latent image pattern;
- calculating means for calculating, based on said surface potential and said amount of toner, an instantaneous state amount relating to a developing characteristic;
- and
- executing means for executing aging of a developer on the basis of said state amount such that a desired developing characteristic is set up, a toner replenishing condition being set after said aging.
Dependencies are inferred from the claim text.