# US 11,215,942 B2 · Image forming apparatus, transfer method, and storage medium storing transfer control program > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,215,942 B2 - Document ID: US11215942B2 - Status: Granted - Kind: B2 - Application number: 16/773,188 - Filed: 2020-01-27 - Published: 2020-08-13 - Granted: 2022-01-04 - Earliest claimed: 2019-02-12 - Assignees: Konica Minolta, Inc. - Applicants: Konica Minolta, Inc. - Inventors: Remi Ishikawa; Eiji Nishikawa; Satoshi Miyajima; Masayuki Fukunaga - Web page: https://patentgrep.com/patent/US11215942B2 ## CPC - G03G 15/1615: {relating to the driving mechanism for the intermediate support, e.g. gears, couplings, belt tensioning} - B65H 29/16: by contact of one face only with moving tapes, bands, or chains {(with suction belts B65H29/242)} - B65H 43/00: Use of control, checking, or safety devices, e.g. automatic devices comprising an element for sensing a variable - G03G 15/5054: {by measuring the characteristics of an intermediate image carrying member or the characteristics of an image on an intermediate image carrying member, e.g. intermediate transfer belt or drum, conveyor belt} - B65H 2403/512: involving radial plate cam - B65H 2404/2692: Arrangement of belts in pressure contact with a roll of material - B65H 2511/13: Thickness - B65H 2513/10: Speed - B65H 2515/34: Pressure, e.g. fluid pressure - B65H 2555/25: D.C. motors, e.g. shunt motors - B65H 2801/06: Office-type machines, e.g. photocopiers - G03G 2215/0193: transfer member separable from recording member - G03G 2215/16: Transferring device, details - G03G 2221/1642: for the transfer unit - G03G: ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY - B65H: HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES ## Abstract An image forming apparatus that has a transfer device that includes an intermediate transfer belt that is tensioned by a plurality of support rollers, a secondary transfer roller that faces one of the support rollers via the intermediate transfer belt, a cam that adjust a pressing force that presses the intermediate transfer belt by the secondary transfer roller, a motor that drives the cam, and a conveyor that conveys a recording medium to a transfer nip formed between the intermediate transfer belt and the secondary transfer roller is provided with a controller that controls an operation of the motor. The controller executes first control of operating the motor with a constant torque and stopping the motor when a rotation angular speed of the motor is less than or equal to a first threshold and second control of operating the motor at a predetermined timing to adjust a transfer nip amount. ## Claims ### Claim 1 An image forming apparatus that has a transfer device that includes an intermediate transfer belt that is tensioned by a plurality of support rollers, a secondary transfer roller that faces one of said support rollers with said intermediate transfer belt interposed between said one of said support roller and said secondary transfer roller, a cam that can adjust a pressing force that presses said intermediate transfer belt by said secondary transfer roller, a motor that drives said cam, and a conveyor that conveys a recording medium to a transfer nip formed between said intermediate transfer belt and said secondary transfer roller, said image forming apparatus comprising: a detector that detects a rotation angle of said motor; and a hardware processor that controls an operation of said motor, wherein said hardware processor executes first control of operating said motor with a constant torque and stopping said motor when a rotation angular speed of said motor is less than or equal to a first threshold determined in advance and second control of operating said motor at a predetermined timing to adjust a transfer nip amount. ### Claim 2 (depends on 1) The image forming apparatus as claimed in claim 1, wherein said hardware processor executes said first control before said recording medium enters said transfer nip. ### Claim 3 (depends on 2) The image forming apparatus as claimed in claim 2, wherein in said second control, immediately before said recording medium enters said transfer nip, said hardware processor drives said motor so as to reduce said pressing force within a range that said secondary transfer roller is not separated from said intermediate transfer belt. ### Claim 4 (depends on 1) The image forming apparatus as claimed in claim 1, wherein said hardware processor executes said first control in a state where said recording medium is nipped between said intermediate transfer belt and said secondary transfer roller. ### Claim 5 (depends on 4) The image forming apparatus as claimed in claim 4, wherein in said second control, immediately before said recording medium is discharged from said transfer nip, said hardware processor drives said motor so as to reduce said pressing force within a range that said secondary transfer roller is not separated from said recording medium. ### Claim 6 (depends on 1) The image forming apparatus as claimed in claim 1, wherein in said first control, said hardware processor drives said motor with a torque at a time when said rotation angular speed of said motor is more than or equal to a second threshold determined in advance. ### Claim 7 (depends on 6) The image forming apparatus as claimed in claim 6, wherein said second threshold is determined depending on an inter-sheet time or a sheet size. ### Claim 8 (depends on 1) The image forming apparatus as claimed in claim 1, wherein said transfer device further includes a transmission mechanism that includes a member whose one end is disposed at a position where said one end can abut against said cam and whose another end is disposed at a position where said another end can abut against said secondary transfer roller and a spring that is disposed at a position where said another end faces said secondary transfer roller, and in said second control, when said cam is separated from said one end of said member, said spring presses said another end of said member and thus said pressing force of said secondary transfer roller is increased, and when said cam presses said one end of said member, said another end of said member presses said spring, and thus said pressing force of said secondary transfer roller is reduced. ### Claim 9 (depends on 1) The image forming apparatus as claimed in claim 1, wherein in said first control, when said rotation angular speed of said motor at a predetermined time is less than a past rotation angular speed stored in advance, said hardware processor determines that said cam abuts against said secondary transfer roller or one end of said member. ### Claim 10 A transfer method in an image forming apparatus that has a transfer device that includes an intermediate transfer belt that is tensioned by a plurality of support rollers, a secondary transfer roller that faces one of said support rollers with said intermediate transfer belt interposed between said one of said support roller and said secondary transfer roller, a cam that can adjust a pressing force that presses said intermediate transfer belt by said secondary transfer roller, a motor that drives said cam, a detector that detects a rotation angle of said motor, and a conveyor that conveys a recording medium to a transfer nip formed between said intermediate transfer belt and said secondary transfer roller, said transfer method comprising: performing first processing of operating said motor with a constant torque and stopping said motor when a rotation angular speed of said motor is less than or equal to a first threshold determined in advance; and performing second processing of operating said motor at a predetermined timing to adjust a transfer nip amount. ### Claim 11 (depends on 10) The transfer method as claimed in claim 10, wherein said first processing is performed before said recording medium enters said transfer nip. ### Claim 12 (depends on 11) The transfer method as claimed in claim 11, wherein in said second processing, immediately before said recording medium enters said transfer nip, said motor is driven so as to reduce said pressing force within a range that said secondary transfer roller is not separated from said intermediate transfer belt. ### Claim 13 (depends on 10) The transfer method as claimed in claim 10, wherein said first processing is performed in a state where said recording medium is nipped between said intermediate transfer belt and said secondary transfer roller. ### Claim 14 (depends on 13) The transfer method as claimed in claim 13, wherein in said second processing, immediately before said recording medium is discharged from said transfer nip, said motor is driven so as to reduce said pressing force within a range that said secondary transfer roller is not separated from said recording medium. ### Claim 15 (depends on 10) The transfer method as claimed in claim 10, wherein in said first processing, said motor is driven with a torque at a time when said rotation angular speed of said motor is more than or equal to a second threshold determined in advance. ### Claim 16 (depends on 15) The transfer method as claimed in claim 15, wherein said second threshold is determined depending on an inter-sheet time or a sheet size. ### Claim 17 (depends on 10) The transfer method as claimed in claim 10, wherein said transfer device further includes a transmission mechanism that includes a member whose one end is disposed at a position where said one end can abut against said cam and whose another end is disposed at a position where said another end can abut against said secondary transfer roller and a spring that is disposed at a position where said another end faces said secondary transfer roller, and in said second processing, when said cam is separated from said one end of said member, said spring presses said another end of said member and thus said pressing force of said secondary transfer roller is increased, and when said cam presses said one end of said member, said another end of said member presses said spring, and thus said pressing force of said secondary transfer roller is reduced. ### Claim 18 (depends on 10) The transfer method as claimed in claim 10, wherein in said first processing, when said rotation angular speed of said motor at a predetermined time is less than a past rotation angular speed stored in advance, it is determined that said cam abuts against said secondary transfer roller or one end of said member. ### Claim 19 A non-transitory computer-readable storage medium storing a transfer control program operating in an image forming apparatus that has a transfer device that includes an intermediate transfer belt that is tensioned by a plurality of support rollers, a secondary transfer roller that faces one of said support rollers with said intermediate transfer belt interposed between said one of said support roller and said secondary transfer roller, a cam that can adjust a pressing force that presses said intermediate transfer belt by said secondary transfer roller, a motor that drives said cam, a detector that detects a rotation angle of said motor, a controller that controls an operation of said motor, and a conveyor that conveys a recording medium to a transfer nip formed between said intermediate transfer belt and said secondary transfer roller, said transfer control program causing said controller to perform: first processing of operating said motor with a constant torque and stopping said motor when a rotation angular speed of said motor is less than or equal to a first threshold determined in advance; and second processing of operating said motor at a predetermined timing to adjust a transfer nip amount.