# US 12,759,827 B2 · Medium conveying apparatus to correct skew of medium using second roller while moving first roller to be spaced apart from medium > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 12,759,827 B2 - Document ID: US12759827B2 - Status: Granted - Kind: B2 - Application number: 18/988,761 - Filed: 2024-12-19 - Published: 2025-04-24 - Granted: 2026-10-13 - Earliest claimed: 2021-01-22 - Assignees: Pfu Limited - Applicants: Pfu Limited - Inventors: Shogo Yoshita - Web page: https://patentgrep.com/patent/US12759827B2 ## CPC - B65H 9/002: {changing orientation of sheet by only controlling movement of the forwarding means, i.e. without the use of stop or register wall} - B65H 1/04: adapted to support articles substantially horizontally, e.g. for separation from top of pile - B65H 3/0684: {on moving support, e.g. pivoting, for bringing the roller or like rotary separator into contact with the pile} - B65H 7/08: responsive to incorrect front register - B65H 7/18: Modifying or stopping actuation of separators - B65H 7/20: Controlling associated apparatus - B65H 9/18: Assisting by devices such as reflectors, lenses, transparent sheets, or mechanical indicators - B65H 2301/331: Skewing, correcting skew, i.e. changing slightly orientation of material - B65H 2553/40: using optical, e.g. photographic, elements - B65H 2553/51: Encoders, e.g. linear - B65H: HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES ## Abstract A medium conveying apparatus includes a first roller to convey a medium, a movement mechanism to move the first roller between a first position in contact with the medium and a second position spaced apart from the medium, a second roller located on a downstream side of the first roller in a medium conveying direction to convey the medium, and a processor to detect a skew of the conveyed medium, and control the movement mechanism to move the first roller to the second position, and correct the skew of the medium using the second roller when the skew of the medium is detected. ## Claims ### Claim 1 A medium conveying apparatus comprising: a first roller to convey a medium; a solenoid or a motor, to move the first roller between a first position in contact with the medium and a second position spaced apart from the medium; a second roller located on a downstream side of the first roller in a medium conveying direction to convey the medium; a medium sensor located in a central portion in a direction intersecting with the medium conveying direction; a plurality of second medium sensors located apart from each other in the direction intersecting with the medium conveying direction; and a processor to determine whether a skew of the conveyed medium has occurred based on output signals from the second medium sensors, and control the solenoid or the motor to move the first roller to the second position when it is determined that the skew of the conveyed medium has occurred, control the solenoid or the motor to return the first roller to the first position when the medium sensor detects passage of a front end of the conveyed medium after moving the first roller to the second position, and execute a correction of the skew of the conveyed medium, using the second roller. ### Claim 2 (depends on 1) The medium conveying apparatus according to claim 1, further comprising a medium tray, wherein the first roller is a pick roller to convey the medium placed on the medium tray. ### Claim 3 (depends on 1) The medium conveying apparatus according to claim 1, wherein the second roller is a plurality of feed rollers located apart from each other in the direction intersecting with the medium conveying direction to feed the medium by rotating independently, respectively, and wherein the processor corrects the skew of the medium by making circumferential speeds of the feed rollers vary from each other. ### Claim 4 (depends on 1) The medium conveying apparatus according to claim 1, further comprising a third roller located on a downstream side of the second roller in the medium conveying direction, wherein the medium sensor is located between the second roller and the third roller in the medium conveying direction. ### Claim 5 (depends on 1) The medium conveying apparatus according to claim 1, further comprising an imaging device located on a downstream side of the plurality of second medium sensors in the medium conveying direction; and the medium sensor is located between the plurality of second medium sensors and the imaging device in the medium conveying direction. ### Claim 6 (depends on 1) The medium conveying apparatus according to claim 1, wherein the processor controls the solenoid or the motor to move the first roller to the second position when the conveyed medium first passes through a position of any of the plurality of second medium sensors. ### Claim 7 (depends on 1) The medium conveying apparatus according to claim 1, further comprising a third medium sensor located on an upstream side of the medium sensor in the medium conveying direction, wherein the processor controls the solenoid or the motor to move the first roller to the second position when the conveyed medium passes through a position of the third medium sensor. ### Claim 8 A method for correcting a skew of a medium, comprising: conveying the medium, by a first roller; moving the first roller between a first position in contact with the medium and a second position spaced apart from the medium, by a solenoid or a motor; conveying the medium, by a second roller located on a downstream side of the first roller in a medium conveying direction; detecting the skew of the conveyed medium based on output signals from a plurality of second medium sensors located apart from each other in a direction intersecting with the medium conveying direction; controlling the solenoid or the motor to move the first roller to the second position when the skew of the conveyed medium is detected; controlling the solenoid or the motor to return the first roller to the first position when a medium sensor located in a central portion in the direction intersecting with the medium conveying direction detects passage of a front end of the conveyed medium after moving the first roller to the second position, and executing a correction of the skew of the conveyed medium, using the second roller. ### Claim 9 (depends on 8) The method according to claim 8, wherein the first roller is a pick roller to convey the medium placed on a medium tray. ### Claim 10 (depends on 8) The method according to claim 8, wherein the second roller is a plurality of feed rollers located apart from each other in the direction intersecting with the medium conveying direction to feed the medium by rotating independently, respectively, and wherein the skew of the medium is corrected by making circumferential speeds of the feed rollers vary from each other. ### Claim 11 (depends on 8) The method according to claim 8, wherein the medium sensor is located between the second roller and a third roller located on a downstream side of the second roller in the medium conveying direction. ### Claim 12 (depends on 8) The method according to claim 8, wherein the solenoid or the motor is controlled to move the first roller to the second position when the conveyed medium passes through a position of a third medium sensor located on an upstream side of the medium sensor in the medium conveying direction. ### Claim 13 A computer-readable, non-transitory medium storing a computer program, wherein the computer program causes a medium conveying apparatus including a first roller to convey a medium, a solenoid or a motor to move the first roller between a first position in contact with the medium and a second position spaced apart from the medium, a second roller located on a downstream side of the first roller in a medium conveying direction to convey the medium, a medium sensor located in a central portion in a direction intersecting with the medium conveying direction, and a plurality of second medium sensors located apart from each other in the direction intersecting with the medium conveying direction, to execute a process, the process comprising: detecting the skew of the conveyed medium based on output signals from the plurality of second medium sensors; controlling the solenoid or the motor to move the first roller to the second position when the skew of the conveyed medium is detected; controlling the solenoid or the motor to return the first roller to the first position when the medium sensor detects passage of a front end of the conveyed medium after moving the first roller to the second position; and executing a correction of the skew of the conveyed medium, using the second roller. ### Claim 14 (depends on 13) The computer-readable, non-transitory medium according to claim 13, wherein the medium conveying apparatus further includes a medium tray, and wherein the first roller is a pick roller to convey the medium placed on the medium tray. ### Claim 15 (depends on 13) The computer-readable, non-transitory medium according to claim 13, wherein the second roller is a plurality of feed rollers located apart from each other in the direction intersecting with the medium conveying direction to feed the medium by rotating independently, respectively, and wherein the skew of the medium is corrected by making circumferential speeds of the feed rollers vary from each other. ### Claim 16 (depends on 13) The computer-readable, non-transitory medium according to claim 13, wherein the medium conveying apparatus further includes a third roller located on a downstream side of the second roller in the medium conveying direction, and wherein the medium sensor is located between the second roller and the third roller in the medium conveying direction. ### Claim 17 (depends on 13) The computer-readable, non-transitory medium according to claim 13, wherein the medium conveying apparatus further includes a third medium sensor located on an upstream side of the medium sensor in the medium conveying direction, and wherein the solenoid or the motor is controlled to move the first roller to the second position when the conveyed medium passes through a position of the third medium sensor.