Back to results
US 11,454,926 B2Granted
Image forming apparatus
AssigneeCanon Kabushiki Kaisha
InventorsTomoaki Nakai, Shizuma Nishimura, Masaki Shimomura
Life of this patent
Estimating the term…
Abstract
A controller is configured to execute a larger gamut technology mode in which the controller performs image formation by controlling a ratio of a rotation speed of a development roller to a rotation speed of a photosensitive drum such that the ratio becomes a second speed ratio higher than a first speed ratio in a normal mode. The controller is configured to, when the controller executes the larger gamut technology mode, control transfer voltage based on a humidity around an image forming apparatus.
Claims24
An image forming apparatus comprising:
- an image forming unit including an image bearing member configured to bear a toner image, and a developing member disposed to face the image bearing member, and configured to develop an electrostatic latent image, formed on the image bearing member, with toner;
- a movable belt configured to come into contact with the image bearing member;
- a transfer member provided at a position corresponding to the image bearing member with the belt interposed between the transfer member and the image bearing member, the transfer member being configured to transfer a toner image from the image bearing member to the belt;
- a transfer power supply configured to apply voltage to the transfer member;
- and
- a control unit configured to execute a first mode and a second mode, the first mode being a mode in which the control unit performs image formation by controlling a speed ratio of a rotation speed of the developing member to a rotation speed of the image bearing member such that the speed ratio becomes a first speed ratio, the second mode being a mode in which the control unit performs image formation by controlling the speed ratio of the rotation speed of the developing member to the rotation speed of the image bearing member such that the speed ratio becomes a second speed ratio higher than the first speed ratio,
- wherein the control unit controls the voltage that is applied from the transfer power supply to the transfer member based on information about a durability of the image forming unit, and
- wherein the control unit is configured to, in the second mode, control the voltage that is applied from the transfer power supply to the transfer member such that the value of current flowing from the transfer member toward the image bearing member in a case where the durability is a first durability in a surrounding environment is greater than the value of current flowing from the transfer member toward the image bearing member in a case where the durability is a second durability, which is lower than the first durability, in the surrounding environment.
5 more elements
An image forming apparatus comprising:
- an image forming unit including an image bearing member configured to bear a toner image, and a developing member disposed to face the image bearing member, and configured to develop an electrostatic latent image, formed on the image bearing member, with toner;
- an intermediate transfer member to which a toner image born on the image bearing member is primarily transferred;
- a transfer member configured to come into contact with the intermediate transfer member to form a transfer portion, the transfer member being configured to secondarily transfer the toner image, primarily transferred from the image bearing member to the intermediate transfer member, from the intermediate transfer member to a transfer material;
- a transfer power supply configured to apply voltage to the transfer member;
- and
- a control unit configured to execute a first mode and a second mode, the first mode being a mode in which the control unit performs image formation by controlling a speed ratio of a rotation speed of the developing member to a rotation speed of the image bearing member such that the speed ratio becomes a first speed ratio, the second mode being a mode in which the control unit performs image formation by controlling the speed ratio of the rotation speed of the developing member to the rotation speed of the image bearing member such that the speed ratio becomes a second speed ratio higher than the first speed ratio,
- wherein the control unit controls the voltage that is applied from the transfer power supply to the transfer member based on information about a durability of the image forming unit, and
- wherein the control unit is configured to, in the second mode, control the voltage that is applied from the transfer power supply to the transfer member such that the value of current flowing from the transfer member toward the intermediate transfer member in a case where the durability is a first durability in a surrounding environment is greater than the value of current flowing from the transfer member toward the intermediate transfer member in a case where the durability is a second durability, which is lower than the first durability, in the surrounding environment.
5 more elements
Dependencies are inferred from the claim text.