Developing device
AssigneeKonica Minolta Business Technologies, Inc.
InventorTomoyuki Imura
Life of this patent
Estimating the term…
Abstract
A developing device has a voltage application member which is in contact via a toner layer with a developing roller that rotates while holding the toner layer on its outer peripheral surface. A voltage that the voltage application member applies to the toner layer is switched between AC voltage and DC voltage based on humidity or drive cumulated time of the developing device.
Claims16
A developing device comprising a voltage application member which is in contact via a toner layer with a developing roller that rotates while holding the toner layer on its outer peripheral surface, wherein
- a voltage that the voltage application member applies to the toner layer is switched between AC voltage and DC voltage based on a condition for toner chargeability.
An image formation apparatus for forming an image by developing an electrostatic latent image formed on a photoconductor by using a developing device and moreover transferring a developed toner image onto a paper sheet, wherein
- the developing device comprises:
- a developing roller which is placed in opposition to the photoconductor and which holds a toner layer on an outer peripheral surface thereof;
- a voltage application member which is placed in contact with the developing roller and which electrically charges the toner layer held on the developing roller;
- a power supply capable of applying an AC voltage or a DC voltage to the voltage application member;
- an environmental condition sensor for detecting an environmental condition within the image formation apparatus;
- and
- a control unit for performing control of switching between the AC voltage and the DC voltage based on an output from the environmental condition sensor.
An image formation apparatus for forming an image by developing an electrostatic latent image formed on a photoconductor by using a developing device and moreover transferring a developed toner image onto a paper sheet, wherein
- the developing device comprises:
- a developing roller which is placed in opposition to the photoconductor and which holds a toner layer on an outer peripheral surface thereof;
- a voltage application member which is placed in contact with the developing roller and which electrically charges the toner layer held on the developing roller;
- a power supply capable of applying an AC voltage or a DC voltage to the voltage application member;
- a counter for cumulatively totalizing drive time of the developing device;
- and
- a control unit for performing control of switching between the AC voltage and the DC voltage based on an output from the counter.
An image formation apparatus for forming an image by developing an electrostatic latent image formed on a photoconductor by using a developing device and moreover transferring a developed toner image onto a paper sheet, wherein
- the developing device comprises:
- a developing roller which is placed in opposition to the photoconductor and which holds a toner layer on an outer peripheral surface thereof;
- a voltage application member which is placed in contact with the developing roller and which electrically charges the toner layer held on the developing roller;
- a power supply capable of applying an AC voltage or a DC voltage to the voltage application member;
- a humidity sensor for detecting a humidity within the image formation apparatus;
- a counter for cumulatively totalizing drive time of the developing device;
- and
- a control unit for performing control of switching between the AC voltage and the DC voltage based on respective outputs from the humidity sensor and the counter.
Dependencies are inferred from the claim text.