# US 8,465,012 B2 · Creasing device and image forming system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 8,465,012 B2 - Document ID: US8465012B2 - Status: Granted - Kind: B2 - Application number: 13/067,061 - Filed: 2011-05-05 - Published: 2011-12-08 - Granted: 2013-06-18 - Earliest claimed: 2010-06-02 - Assignees: Ricoh Company, Ltd. - Applicants: Naoyuki Ishikawa; Hitoshi Hattori; Naohiro Kikkawa; Shuuya Nagasako; Takashi Saito; Yuusuke Shibasaki; Hidetoshi Kojima; Naoki Oikawa; Go Aiba - Inventors: Naoyuki Ishikawa; Hitoshi Hattori; Naohiro Kikkawa; Shuuya Nagasako; Takashi Saito; Yuusuke Shibasaki; Hidetoshi Kojima; Naoki Oikawa; Go Aiba - Web page: https://patentgrep.com/patent/US8465012B2 ## CPC - B65H 45/30: Folding in combination with creasing, smoothing or application of adhesive (folding or adhesive application in article or web delivering B65H37/00) - B31F 1/08: Creasing (corrugating B31F1/20; zig-zag folding B65H45/20 {; combined with folding B31F1/0012, B31F1/0022; grooving by cutting B26D3/06, B26D3/08; by milling grooves B23C3/30; of plastics material B29C53/06}) - B65H 45/18: Oscillating or reciprocating blade folders (carried on rotary members B65H45/16) - B65H 2801/27: Devices located downstream of office-type machines - B65H: HANDLING THIN OR FILAMENTARY MATERIAL, e.g. SHEETS, WEBS, CABLES - B31F: MECHANICAL WORKING OR DEFORMATION OF PAPER, CARDBOARD OR MATERIAL WORKED IN A MANNER ANALOGOUS TO PAPER (making layered products not composed wholly of paper or cardboard B32B) ## Abstract A creasing device that creases sheets on a per-sheet basis and includes: a first member extending perpendicularly to a sheet conveying direction and including a convex blade; a second member extending perpendicularly to the sheet conveying direction and including a concave blade, into which the convex blade is to be fitted; a drive unit that brings the first and the second members into and out of contact with each other, thereby producing a crease in a sheet interposed between the first and the second members; a sheet retainer driven by the drive unit and brought into contact with the second member with the sheet therebetween to retain the sheet across its full width; and a holding unit that holds the sheet retainer in a retaining state during creasing where the contact between the first and the second members starts at one point and develops in one direction. ## Claims ### Claim 1 A creasing device that creases sheets on a per-sheet basis, the creasing device comprising: a first member extending in a direction perpendicular to a sheet conveying direction and including a creasing blade, the; a second member extending in a direction perpendicular to the sheet conveying direction and including a creasing channel, the creasing channel allowing the creasing blade to be fitted thereinto with a sheet interposed between the creasing channel and the creasing blade; a drive unit that brings the first member and the second member into and out of contact with each other to cause a sheet stopped at a predetermined position to be pinched between the first and the second members and creased; a sheet retainer driven by the drive unit and brought into contact with a top surface of the second member with the sheet interposed between the sheet retainer and the second member to retain the sheet across a full width of the sheet; and a holding unit that holds the sheet retainer in a retaining state during creasing where the creasing blade and the creasing channel come into contact with each other with the sheet interposed therebetween, the contact starting at one point and developing in one direction, wherein the creasing blade and the creasing channel are configured to come into contact with each other starting at a first end of the first member and proceeding linearly to a second end of the first member. ### Claim 2 (depends on 1) The creasing device of claim 1, wherein the sheet retainer includes: a sheet retaining member that is longer than a length of the sheet in a direction, along which the sheet is creased, and is configured to be brought into contact with the sheet on a straight contact line; and that the drive unit moves the sheet retaining member toward and away from the second member, and the sheet retainer is driven by the drive unit in synchronization with the first member. ### Claim 3 (depends on 1) The creasing device of claim 1, wherein a position of the one point where the contact between the creasing blade and the creasing channel starts is a position where sheets of any size do not pass through. ### Claim 4 (depends on 1) The creasing device of claim 1, wherein the creasing blade and the creasing channel start separating from each other from a side where the contact between the creasing blade and the creasing channel starts. ### Claim 5 (depends on 1) The creasing device of claim 1, wherein a traveling speed of the sheet retainer decreases immediately before the sheet retainer comes into contact with the sheet. ### Claim 6 (depends on 1) The creasing device of claim 1, wherein a traveling speed of the sheet retainer increases after the sheet retainer has been separated from the sheet. ### Claim 7 (depends on 1) The creasing device of claim 1, further comprising a pressure changing unit that changes a pressure to be exerted by the sheet retainer on the sheet depending on a thickness of the sheet. ### Claim 8 (depends on 1) The creasing device of claim 1, further comprising a pressure changing unit that changes a pressure to be exerted by the sheet retainer on the sheet according to information about whether the sheet is special paper. ### Claim 9 (depends on 1) The creasing device of claim 1, wherein a pressure to be exerted by the sheet retainer on the sheet is changed depending on a print area in a portion where the sheet retainer is in contact with the sheet. ### Claim 10 An image forming system comprising: a creasing device that crease sheets on a per-sheet basis; and an image forming apparatus that forms an image on the sheets, wherein the creasing device comprises: a first member extending in a direction perpendicular to a sheet conveying direction and including a creasing blade; a second member extending in a direction perpendicular to the sheet conveying direction and including a creasing channel, the creasing channel allowing the creasing blade to be fitted thereinto with a sheet interposed between the creasing channel and the creasing blade; a drive unit that brings the first member and the second member into and out of contact with each other to cause a sheet stopped at a predetermined position to be pinched between the first and the second members and creased; a sheet retainer driven by the drive unit and brought into contact with a top surface of the second member with the sheet interposed between the sheet retainer and the second member to retain the sheet across a full width of the sheet; and a holding unit that holds the sheet retainer in a retaining state during creasing where the creasing blade and the creasing channel come into contact with each other with the sheet interposed therebetween, the contact starting at one point and developing in one direction, wherein the creasing blade and the creasing channel are configured to come into contact with each other starting at a first end of the first member and proceeding linearly to a second end of the first member.