# US 2014/0197593 A1 · Sheet feeding apparatus and 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 2014/0197593 A1 - Document ID: US20140197593A1 - Status: Published application - Kind: A1 - Application number: 14/146,071 - Filed: 2014-01-02 - Published: 2014-07-17 - Earliest claimed: 2013-01-11 - Assignees: Canon Kabushiki Kaisha - Applicants: Canon Kabushiki Kaisha - Inventors: Emi Machii; Koji Kawamura - Web page: https://patentgrep.com/patent/US20140197593A1 ## CPC - B65H 3/66: Article guides or smoothers, e.g. movable in operation - B65H 3/0676: {with two or more separator rollers in the feeding direction} - B65H 3/5261: {Retainers of the roller type, e.g. rollers} - B65H 3/56: Elements, e.g. scrapers, fingers, needles, brushes, acting on separated article or on edge of the pile {(B65H3/52 takes precedence)} - B65H 5/062: {between rollers or balls} - B65H 5/068: {between one or more rollers or balls and stationary pressing, supporting or guiding elements} - B65H 2402/31: Pivoting support means - B65H 2402/32: Sliding support means - B65H 2404/1341: Elastic mounting, i.e. subject to biasing means - B65H: HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES ## Abstract Disclosed are a sheet feeding apparatus and an image forming apparatus capable of reliably separating and feeding sheets one by one without delay and damage to a sheet for a high speed of a printer or the like. A sheet feeding portion has a nip guide member having a sloped guide surface sloped so as to guide a leading end of a sheet to a separation nip portion such that a guide leading-end is biased to a feed roller with a predetermined distance from the feed roller. A support member supports the nip guide member not to recede from the feed roller when a thickness of a sheet bundle bumping into the sloped guide surface is smaller than a predetermined distance between the feed roller and the guide leading-end and supports the nip guide member to recede from the feed roller when the thickness is larger than the predetermined distance. ## Claims ### Claim 1 A sheet feeding apparatus comprising: a conveying roller; a separation member which presses against the conveying roller to form a separation nip portion that separates received sheets one by one; a nip guide member having a sloped guide surface whose guide leading-end receives a force toward the conveying roller in a position distant from the conveying roller with a predetermined distance to slope so as to guide a leading end of a sheet to the separation nip portion; and a support member which supports the nip guide member not to recede from the conveying roller when a thickness of a sheet bundle bumping into the sloped guide surface is smaller than the predetermined distance between the conveying roller and the guide leading-end and supports the nip guide member to recede from the conveying roller when the thickness is larger than the predetermined distance. ### Claim 2 (depends on 1) The sheet feeding apparatus according to claim 1, wherein the support member has a rotation shaft that rotatably supports the nip guide member, and a rotation center of the rotation shaft is provided in an area interposed between a first straight line extending opposite to the conveying roller and perpendicularly to the sloped guide surface and a second straight line that connects a rotation center of the conveying roller and the guide leading-end in an abutment portion where a leading end of a fed sheet abuts on the sloped guide surface. ### Claim 3 (depends on 1) The sheet feeding apparatus according to claim 1, wherein the support member has a rotation shaft that rotatably supports the nip guide member, and a rotation center of the rotation shaft is provided in an area interposed between a first straight line extending perpendicularly to the sloped guide surface and a second straight line that connects a rotation center of the conveying roller and the guide leading-end in an abutment portion where a leading end of a fed sheet abuts on the sloped guide surface. ### Claim 4 (depends on 2, 3) The sheet feeding apparatus according to claim 2 or 3, wherein the area where the rotation center of the conveying roller is located includes the first straight line and does not include the second straight line. ### Claim 5 (depends on 2, 3) The sheet feeding apparatus according to claim 2 or 3, wherein the nip guide member is slidably supported by the support member, and a slide direction of the nip guide member matches a direction of an approximate straight line of a virtual arc whose distant rotation center exists at infinity in an area interposed between a first straight line extending perpendicularly to the sloped guide surface and a second straight line that connects a rotation center of the conveying roller and the guide leading-end in an abutment position where a leading end of a fed sheet abuts on the sloped guide surface. ### Claim 6 (depends on 5) The sheet feeding apparatus according to claim 5, wherein the area where the rotation center existing at infinity is located includes the first straight line and does not include the second line. ### Claim 7 (depends on 1) The sheet feeding apparatus according to claim 1, further comprising a sheet storing portion which is capable of loading a plurality of fed sheets and has a restricting wall surface that restricts a leading end of a loaded sheet in a feeding direction, wherein the restricting wall surface is arranged closer to a sheet in the sheet storing portion relative to the nip guide member. ### Claim 8 A sheet feeding apparatus comprising: a conveying roller; a separation member which presses against the conveying roller to form a separation nip portion that separates and feeds received sheets one by one to a downstream side; a nip guide member which is rotatable and has a sloped guide surface sloped toward the separation nip portion to guide a leading end of a sheet to the separation nip portion; a biasing member which applies a force such that a guide leading-end of the nip guide member is directed to the conveying roller; and a restricting portion which performs restriction resisting to a biasing force of the biasing member such that the guide leading-end is close to the conveying roller with a predetermined distance, wherein a rotation center of the nip guide member is provided in an area interposed between a first straight line extending opposite to the conveying roller and perpendicularly to the sloped guide surface and a second straight line that connects a rotation center of the conveying roller and the guide leading-end in an abutment portion where a leading end of a fed sheet abuts on the sloped guide surface. ### Claim 9 (depends on 8) The sheet feeding apparatus according to claim 8, wherein a rotation center of the nip guide member is arranged under the separation nip portion. ### Claim 10 A sheet feeding apparatus comprising: a conveying roller; a separation member which presses against the conveying roller to form a separation nip portion that separates and feeds received sheets one by one to a downstream side; a nip guide member which is rotatable and has a sloped guide surface sloped toward the separation nip portion to guide a leading end of a sheet to the separation nip portion; a biasing member which applies a force such that a guide leading-end of the nip guide member is directed to the conveying roller; and a restricting portion which performs restriction resisting to a biasing force of the biasing member such that the guide leading-end is close to the conveying roller with a predetermined distance, wherein a rotation center of the nip guide member is provided in an area interposed between a first straight line extending opposite to the separation member and perpendicularly to the sloped guide surface and a second straight line that connects a rotation center of the conveying roller and the guide leading-end in an abutment portion where a leading end of a fed sheet abuts on the sloped guide surface. ### Claim 11 (depends on 10) The sheet feeding apparatus according to claim 10, wherein a rotation center of the nip guide member is arranged over the separation nip portion. ### Claim 12 (depends on 8, 11) The sheet feeding apparatus according to claim 8 or 11, wherein the area where the rotation center of the conveying roller is located includes the first straight line and does not include the second straight line. ### Claim 13 An image forming apparatus comprising a sheet feeding apparatus, the sheet feeding apparatus comprising a conveying roller; a separation member which presses against the conveying roller to form a separation nip portion that separates received sheets one by one, a nip guide member having a sloped guide surface whose guide leading-end receives a force toward the conveying roller in a position distant from the conveying roller with a predetermined distance to slope so as to guide a leading end of a sheet to the separation nip portion, and a support member which supports the nip guide member not to recede from the conveying roller when a thickness of a sheet bundle bumping into the sloped guide surface is smaller than the predetermined distance between the conveying roller and the guide leading-end and supports the nip guide member to recede from the conveying roller when the thickness is larger than the predetermined distance, and an image forming portion, in which an image is formed on a sheet fed from the sheet feeding apparatus. ### Claim 14 An image forming apparatus comprising a sheet feeding apparatus, the sheet feeding apparatus having a conveying roller, a separation member which presses against the conveying roller to form a separation nip portion that separates and feeds received sheets one by one to a downstream side, a nip guide member which is rotatable and has a sloped guide surface sloped toward the separation nip portion to guide a leading end of a sheet to the separation nip portion, a biasing member which applies a force such that a guide leading-end of the nip guide member is directed to the conveying roller; and a restricting portion which performs restriction resisting to a biasing force of the biasing member such that the guide leading-end is close to the conveying roller with a predetermined distance, wherein a rotation center of the nip guide member is provided in an area interposed between a first straight line extending opposite to the conveying roller and perpendicularly to the sloped guide surface and a second straight line that connects a rotation center of the conveying roller and the guide leading-end in an abutment portion where a leading end of a fed sheet abuts on the sloped guide surface, and an image forming portion, in which an image is formed on a sheet fed from the sheet feeding apparatus. ### Claim 15 (depends on 14) The image forming apparatus according to claim 14, wherein a rotation center of the nip guide member is arranged over the separation nip portion. ### Claim 16 An image forming apparatus comprising a sheet feeding apparatus, the sheet feeding apparatus having a conveying roller, a separation member which presses against the conveying roller to form a separation nip portion that separates and feeds received sheets one by one to a downstream side, a nip guide member which is rotatable and has a sloped guide surface sloped toward the separation nip portion to guide a leading end of a sheet to the separation nip portion, a biasing member which applies a force such that a guide leading-end of the nip guide member is directed to the conveying roller, and a restricting portion which performs restriction resisting to a biasing force of the biasing member such that the guide leading-end is close to the conveying roller with a predetermined distance, wherein a rotation center of the nip guide member is provided in an area interposed between a first straight line extending opposite to the separation member and perpendicularly to the sloped guide surface and a second straight line that connects a rotation center of the conveying roller and the guide leading-end in an abutment portion where a leading end of a fed sheet abuts on the sloped guide surface. ### Claim 17 (depends on 16) The image forming apparatus according to claim 16, wherein a rotation center of the nip guide member is arranged over the separation nip portion. ### Claim 18 (depends on 14, 16) The image forming apparatus according to claim 14 or 16, wherein the area where the rotation center of the conveying roller is located includes the first straight line and does not include the second straight line. ### Claim 19 (depends on 14, 16) The image forming apparatus according to claim 14 or 16, wherein the nip guide member is slidably supported by the support member, and a slide direction of the nip guide member matches a direction of an approximate straight line of a virtual arc having an infinitely distant rotation center in an area interposed between a first straight line extending perpendicularly to the sloped guide surface and a second straight line that connects a rotation center of the conveying roller and the guide leading-end in an abutment position where a leading end of a fed sheet abuts on the sloped guide surface. ### Claim 20 (depends on 19) The image forming apparatus according to claim 19, wherein the area where the infinitely distant rotation center is located includes the first straight line and does not include the second straight line. ### Claim 21 (depends on 13) The image forming apparatus according to claim 13, further comprising a sheet storing portion which is capable of storing a plurality of fed sheets and has a restricting wall surface that restricts a leading end of a fed sheet in a feeding direction, wherein the restricting wall surface is arranged closer to a sheet in the sheet storing portion relative to the nip guide member. ### Claim 22 (depends on 14, 16) The image forming apparatus according to claim 14 or 16, wherein a rotation center of the nip guide member is arranged under the separation nip portion.