Back to results
US 2006/0140653 A1Published application
Image forming apparatus
AssigneeCanon Kabushiki Kaisha
InventorTadanobu Yoshikawa
Life of this patent
Estimating the term…
Abstract
A pulse-like DC voltage is applied from two power sources to transfer residual toner uniformizing means and toner charge amount control means, respectively, to expel transfer residual toner deposited on these means from these means onto a photosensitive drum. In a low humidity environment, the number of application of the DC voltage is increased so as to sufficiently expel the transfer residual toner because the transfer residual toner is less liable to be expelled even when the pulse-like DC voltage is applied to the above two means in the low humidity environment in which an absolute moisture content in atmosphere is small and electrical resistances at portions of a photosensitive drum contacting the above two means.
Claims14
An image forming apparatus, comprising:
- an image bearing member;
- a contact charging member, disposed in contact with a surface of said image bearing member;
- for electrically charging said image bearing member;
- exposure means for exposing the surface of said image bearing member, after being electrically charged, to light to form an electrostatic latent image;
- developing means for developing the electrostatic latent image with toner to form a toner image and recovering toner remaining on said image bearing member;
- transfer means for transferring the toner image from said image bearing member onto another member;
- an auxiliary charging member, for processing the toner remaining on said image bearing member, disposed downstream from said transfer means and upstream from said contact charging member in a movement direction of the surface of said image bearing member;
- voltage application means for applying a pulse-like direct-current voltage to said auxiliary charging member so as to expel the toner deposited on said auxiliary charging member from said auxiliary charging member onto said image bearing member;
- control means for controlling said voltage application means;
- and
- an environmental sensor for detecting an ambient environment in which said image forming apparatus is set;
- wherein said control means changes the number of times the pulse-like direct-current voltage is applied from said voltage application means to said auxiliary charging member on the basis of a detection result of said environmental sensor.
9 more elements
An image forming apparatus, comprising:
- an image bearing member;
- a contact charging member, disposed in contact with a surface of said image bearing member;
- for electrically charging said image bearing member;
- exposure means for exposing the surface of said image bearing member, after being electrically charged, to light to form an electrostatic latent image;
- developing means for developing the electrostatic latent image with toner to form a toner image and recovering toner remaining on said image bearing member;
- transfer means for transferring the toner image from said image bearing member onto another member;
- an auxiliary charging member, for processing the toner remaining on said image bearing member, disposed downstream from said transfer means and upstream from said contact charging member in a movement direction of the surface of said image bearing member;
- voltage application means for applying a pulse-like direct-current voltage to said auxiliary charging member so as to expel the toner deposited on said auxiliary charging member from said auxiliary charging member onto said image bearing member;
- control means for controlling said voltage application means;
- and
- usage detection means for detecting an amount of usage of said image forming apparatus;
- wherein said control means changes the number of times the pulse-like direct-current voltage is applied from said voltage application means to said auxiliary charging member on the basis of a detection result of said usage detection means.
9 more elements
An image forming apparatus, comprising:
- an image bearing member;
- a contact charging member, disposed in contact with a surface of said image bearing member;
- for electrically charging said image bearing member;
- exposure means for exposing the surface of said image bearing member, after being electrically charged, to light to form an electrostatic latent image;
- developing means for developing the electrostatic latent image with toner to form a toner image and recovering toner remaining on said image bearing member;
- transfer means for transferring the toner image from said image bearing member onto another member;
- an auxiliary charging member, for processing the toner remaining on said image bearing member, disposed downstream from said transfer means and upstream from said contact charging member in a movement direction of the surface of said image bearing member;
- voltage application means for applying a pulse-like direct-current voltage to said auxiliary charging member so as to expel the toner deposited on said auxiliary charging member from said auxiliary charging member onto said image bearing member;
- control means for controlling said voltage application means;
- and
- print ratio detection means for detecting a print ratio of an image;
- wherein said control means changes the number of times the pulse-like direct-current voltage is applied from said voltage application means to said auxiliary charging member on the basis of a detection result of said print ratio detection means.
9 more elements
Dependencies are inferred from the claim text.