# US 10,108,123 B2 · Image forming apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,108,123 B2 - Document ID: US10108123B2 - Status: Granted - Kind: B2 - Application number: 15/713,433 - Filed: 2017-09-22 - Published: 2018-03-29 - Granted: 2018-10-23 - Earliest claimed: 2016-09-29 - Assignees: Canon Kabushiki Kaisha - Applicants: Canon Kabushiki Kaisha - Inventors: Motonari Ito; Kuniaki Tamagaki; Makoto Tokudome - Web page: https://patentgrep.com/patent/US10108123B2 ## CPC - G03G 15/5045: {Detecting the temperature} - G03G 15/0815: {characterised by the developer handling means after the developing zone and before the supply, e.g. developer recovering roller} - G03G 21/0094: {fatigue treatment of the photoconductor} - G03G 21/203: {Humidity} - G03G 15/0808: {characterised by the developer supplying means, e.g. structure of developer supply roller} - G03G 15/0813: {characterised by means in the developing zone having an interaction with the image carrying member, e.g. distance holders} - G03G 15/0896: {Arrangements or disposition of the complete developer unit or parts thereof not provided for by groups G03G15/08 - G03G15/0894} - G03G 15/2035: {for maintenance purposes, e.g. for removing a jammed sheet} - G03G 15/2039: {with means for controlling the fixing temperature} - G03G 15/205: {specially for the mode of operation, e.g. standby, warming-up, error (G03G15/2046 takes precedence)} - G03G 15/5008: {Driving control for rotary photosensitive medium, e.g. speed control, stop position control} - G03G 15/5012: {Priority interrupt; Job recovery, e.g. after jamming or malfunction} - G03G 15/5033: {by measuring the photoconductor characteristics, e.g. temperature, or the characteristics of an image on the photoconductor} - G03G 15/75: {Details relating to xerographic drum, band or plate, e.g. replacing, testing (electrographic recording members per se G03G5/00)} - G03G 15/751: {relating to drum (G03G15/757 takes precedence)} - G03G 21/0005: {for removing solid developer or debris from the electrographic recording medium} - G03G 21/0064: {using the developing unit, e.g. cleanerless or multi-cycle apparatus} - G03G 21/1619: {Frame structures} - G03G 21/1676: {for the developer unit} - G03G 21/1821: {means for connecting the different parts of the process cartridge, e.g. attachment, positioning of parts with each other, pressure/distance regulation (G03G21/1825 takes precedence)} - G03G 21/1825: {Pivotable subunit connection} - G03G 2215/00071: by measuring the photoconductor or its environmental characteristics - G03G 2215/00075: the characteristic being its speed - G03G 2215/0872: Housing of developing device - G03G 2221/0026: Cleaning of foreign matter, e.g. paper powder, from imaging member - G03G 2221/0036: Oil and other liquid matter - G03G 2221/0089: Mechanical - G03G 2221/1609: protective arrangements for preventing damage - G03G: ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY ## Abstract An image forming apparatus includes an image bearing member, a developer bearing member, a fixing unit including a heating member, a rotary member which is heated by the heating member, and a nip area where the rotary member comes into contact with a sheet, and configured to perform fixing by heating a developer image transferred to the sheet and fixing the developer image to the sheet in the nip area, and a control unit configured to execute, while the fixing is not performed, a mode in which the image bearing member is rotated with the developer bearing member being in a separated position and the heating member is controlled such that a temperature of a portion of a surface of the rotary member, after the rotary member passes through the nip area, is maintained higher than the temperature of the portion during the fixing. ## Claims ### Claim 1 An image forming apparatus comprising: an image bearing member configured to be rotatable and bear a developer image; a developer bearing member configured to be rotatable, bear a developer, and supply the developer to a surface of the image bearing member to form the developer image; a switching unit configured to move the developer bearing member between a contact position in which the developer bearing member is in contact with the image bearing member, and a separated position in which the developer bearing member is separated from the image bearing member; and a fixing unit including a heating member, a rotary member which is heated by the heating member, and a nip area where the rotary member comes into contact with a sheet, and configured to perform fixing by heating the developer image transferred to the sheet and fixing the developer image to the sheet in the nip area, wherein when the developer bearing member is in the separated position, a rotation shaft of the image bearing member is located closer to the fixing unit than a rotation shaft of the developer bearing member, the image forming apparatus further comprising a control unit configured to execute, while the fixing is not performed, a mode in which the image bearing member is rotated, with (1) the developer bearing member being in the separated position and (2) the heating member being controlled such that a temperature of a portion of a surface of the rotary member after the rotary member passes through the nip area is maintained higher than the temperature of the portion during the fixing. ### Claim 2 (depends on 1) The image forming apparatus according to claim 1, wherein while the mode is executed, there is a period of time during which a temperature of the surface of the image bearing member is higher than the temperature of the surface of the image bearing member during the fixing. ### Claim 3 (depends on 1) The image forming apparatus according to claim 1, wherein when the developer bearing member is placed in the separated position by the switching unit, the rotation shaft of the image bearing member is located below the fixing unit in a vertical direction and the rotation shaft of the developer bearing member is located below the rotation shaft of the image bearing member in the vertical direction. ### Claim 4 (depends on 1) The image forming apparatus according to claim 1, wherein the developer is a mono component developer, wherein when the image bearing member is in the contact position, the developer is supplied to the surface of the image bearing member, wherein the image bearing member is rotated so that the surface of the image bearing member passes through a charging position in which the surface of the image bearing member is charged by a charging member and a transfer position in which the developer image formed on the surface of the image bearing member is transferred onto a transfer receiving member by a transfer member, and wherein the developer adhering to the surface of the image bearing member after the surface of the image bearing member passes through the transfer position is collectable from the surface of the image bearing member by the developer bearing member. ### Claim 5 (depends on 1) The image forming apparatus according to claim 1, wherein the control unit performs the rotation control with the developer bearing member being stopped rotating. ### Claim 6 An image forming apparatus comprising: an image bearing member configured to be rotatable and bear a developer image; a developer bearing member configured to be rotatable, bear a developer, and supply—the developer to a surface of the image bearing member to form the developer image; a switching unit configured to move the developer bearing member between a contact position in which the developer bearing member is in contact with the image bearing member, and a separated position in which the developer bearing member is separated from the image bearing member; and a fixing unit including a heating member, a rotary member which is heated by the heating member, and a frame which supports the rotary member, and configured to perform fixing by heating the developer image transferred to a sheet and fixing the developer image to the sheet, wherein when the developer bearing member is in the separated position, a rotation shaft of the image bearing member is located closer to the fixing unit than a rotation shaft of the developer bearing member, the image forming apparatus further comprising a control unit configured to execute, while the fixing is not performed, a mode in which the image bearing member is rotated, with (1) the developer bearing member being in the separated position and (2) a temperature of a closest portion of a surface of the frame to the image bearing member being maintained higher than the temperature of the closest portion during the fixing. ### Claim 7 (depends on 6) The image forming apparatus according to claim 6, wherein while the mode is executed, there is a period of time during which a temperature of the surface of the image bearing member is higher than the temperature of the surface of the image bearing member during the fixing. ### Claim 8 (depends on 6) The image forming apparatus according to claim 6, wherein when the developer bearing member is placed in the separated position by the switching unit, the rotation shaft of the image bearing member is located below the fixing unit in a vertical direction and the rotation shaft of the developer bearing member is located below the rotation shaft of the image bearing member in the vertical direction. ### Claim 9 (depends on 6) The image forming apparatus according to claim 6, wherein the developer is a mono component developer, wherein when the image bearing member is in the contact position, the developer is supplied to the surface of the image bearing member, wherein the image bearing member is rotated so that the surface of the image bearing member passes through a charging position in which the surface of the image bearing member is charged by a charging member and a transfer position in which the developer image formed on the surface of the image bearing member is transferred onto a transfer receiving member by a transfer member, and wherein the developer adhering to the surface of the image bearing member after the surface of the image bearing member passes through the transfer position is collectable from the surface of the image bearing member by the developer bearing member. ### Claim 10 (depends on 6) The image forming apparatus according to claim 6, wherein the control unit performs the rotation control with the developer bearing member being stopped rotating. ### Claim 11 An image forming apparatus comprising: an image bearing member configured to be rotatable and bear a developer image; a developer bearing member configured to be rotatable, bear a developer, and supply the developer to a surface of the image bearing member to form the developer image; a switching unit configured to move the developer bearing member between a contact position in which the developer bearing member is in contact with the image bearing member, and a separated position in which the developer bearing member is separated from the image bearing member; and a fixing unit including a heating member, a rotary member which is heated by the heating member, and a frame which supports the rotary member, and configured to perform fixing to heat the developer image transferred to a sheet and fix the developer image to the sheet, wherein when the developer bearing member is in the separated position, a rotation shaft of the image bearing member is located closer to the fixing unit than a rotation shaft of the developer bearing member, the image forming apparatus further comprising a control unit configured to execute, while the fixing is not performed, a mode in which the image bearing member is rotated, with (1) the developer bearing member being in the separated position and (2) a temperature of air in a space between the fixing unit and the image bearing member being maintained higher than the temperature of the air between the fixing unit and the image bearing member during the fixing. ### Claim 12 (depends on 11) The image forming apparatus according to claim 11, wherein while the mode is executed, there is a period of time during which a temperature of the surface of the image bearing member is higher than the temperature of the surface of the image bearing member during the fixing. ### Claim 13 (depends on 11) The image forming apparatus according to claim 11, wherein when the developer bearing member is placed in the separated position by the switching unit, the rotation shaft of the image bearing member is located below the fixing unit in a vertical direction and the rotation shaft of the developer bearing member is located below the rotation shaft of the image bearing member in the vertical direction. ### Claim 14 (depends on 11) The image forming apparatus according to claim 11, wherein the developer is a mono component developer, wherein when the image bearing member is in the contact position, the developer is supplied to the surface of the image bearing member, wherein the image bearing member is rotated so that the surface of the image bearing member passes through a charging position in which the surface of the image bearing member is charged by a charging member and a transfer position in which the developer image formed on the surface of the image bearing member is transferred onto a transfer receiving member by a transfer member, and wherein the developer adhering to the surface of the image bearing member after the surface of the image bearing member passes through the transfer position is collectable from the surface of the image bearing member by the developer bearing member. ### Claim 15 (depends on 11) The image forming apparatus according to claim 11, wherein the control unit performs the rotation control with the developer bearing member being stopped rotating. ### Claim 16 An image forming apparatus comprising: an image bearing member configured to be rotatable and bear a developer image; a developer bearing member configured to be rotatable, bear a developer, and supply the developer to a surface of the image bearing member to form the developer image; a switching unit configured to move the developer bearing member between a contact position in which the developer bearing member is in contact with the image bearing member, and a separated position in which the developer bearing member is separated from the image bearing member; and a fixing unit including a heating member, a rotary member which is heated by the heating member, and a frame which supports the rotary member, and configured to perform fixing by heating the developer image transferred to a sheet and fixing the developer image to the sheet, wherein when the developer bearing member is in the separated position, a rotation shaft of the image bearing member is located closer to the fixing unit than a rotation shaft of the developer bearing member, the image forming apparatus further comprising a control unit configured to execute, while the fixing is not performed, a mode for evaporating moisture adhering to the surface of the image bearing member in which the image bearing member is rotated, with (1) the developer bearing member being in the separated position and (2) the rotary member being heated by the heating member. ### Claim 17 (depends on 16) The image forming apparatus according to claim 16, wherein while the mode is executed, there is a period of time during which a temperature of the surface of the image bearing member is higher than the temperature of the surface of the image bearing member during the fixing. ### Claim 18 (depends on 16) The image forming apparatus according to claim 16, wherein when the developer bearing member is placed in the separated position by the switching unit, the rotation shaft of the image bearing member is located below the fixing unit in a vertical direction and the rotation shaft of the developer bearing member is located below the rotation shaft of the image bearing member in the vertical direction. ### Claim 19 (depends on 16) The image forming apparatus according to claim 16, wherein the developer is a mono component developer, wherein when the image bearing member is in the contact position, the developer is supplied to the surface of the image bearing member, wherein the image bearing member is rotated so that the surface of the image bearing member passes through a charging position in which the surface of the image bearing member is charged by a charging member and a transfer position in which the developer image formed on the surface of the image bearing member is transferred onto a transfer receiving member by a transfer member, and wherein the developer adhering to the surface of the image bearing member after the surface of the image bearing member passes through the transfer position is collectable from the surface of the image bearing member by the developer bearing member. ### Claim 20 (depends on 16) The image forming apparatus according to claim 16, wherein the control unit performs the rotation control with the developer bearing member being stopped rotating. ### Claim 21 An image forming apparatus comprising: an image bearing member configured to be rotatable and bear a developer image; a developer bearing member configured to be rotatable, bear a developer, and supply the developer to a surface of the image bearing member to form the developer image; a switching unit configured to move the developer bearing member between a contact position in which the developer bearing member is in contact with the image bearing member, and a separated position in which the developer bearing member is separated from the image bearing member; a fixing unit including a heating member, a rotary member which is heated by the heating member, and a frame which supports the rotary member, and configured to perform fixing by heating the developer image transferred to a sheet and fixing the developer image to the sheet; and a humidity detection unit, wherein when the developer bearing member is in the separated position, a rotation shaft of the image bearing member is located closer to the fixing unit than a rotation shaft of the developer bearing member, the image forming apparatus further comprising a control unit configured to execute, while the fixing is not performed, a mode in which the image bearing member is rotated, with (1) the developer bearing member being in the separated position and (2) the rotary member being heated by the heating member, wherein the control unit executes the mode based on output of the humidity detection unit. ### Claim 22 (depends on 21) The image forming apparatus according to claim 21, wherein the control unit calculates an absolute moisture content based on the output of the humidity detection unit, and if the calculated absolute moisture content is not lower than a predetermined threshold value, the control unit executes the mode, whereas if the calculated absolute moisture content is lower than the predetermined threshold value, the control unit does not execute the mode. ### Claim 23 (depends on 21) The image forming apparatus according to claim 21, wherein while the mode is executed, there is a period of time during which a temperature of the surface of the image bearing member is higher than the temperature of the surface of the image bearing member during the fixing. ### Claim 24 (depends on 21) The image forming apparatus according to claim 21, wherein when the developer bearing member is placed in the separated position by the switching unit, the rotation shaft of the image bearing member is located below the fixing unit in a vertical direction and the rotation shaft of the developer bearing member is located below the rotation shaft of the image bearing member in the vertical direction. ### Claim 25 (depends on 21) The image forming apparatus according to claim 21, wherein the developer is a mono component developer, wherein when the image bearing member is in the contact position, the developer is supplied to the surface of the image bearing member, wherein the image bearing member is rotated so that the surface of the image bearing member passes through a charging position in which the surface of the image bearing member is charged by a charging member and a transfer position in which the developer image formed on the surface of the image bearing member is transferred onto a transfer receiving member by a transfer member, and wherein the developer adhering to the surface of the image bearing member after the surface of the image bearing member passes through the transfer position is collectable from the surface of the image bearing member by the developer bearing member. ### Claim 26 (depends on 21) The image forming apparatus according to claim 21, wherein the control unit performs the rotation control with the developer bearing member being stopped rotating.