# US 2013/0156468 A1 · Developing device and image forming apparatus including the same > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2013/0156468 A1 - Document ID: US20130156468A1 - Status: Published application - Kind: A1 - Application number: 13/681,668 - Filed: 2012-11-20 - Published: 2013-06-20 - Earliest claimed: 2011-12-19 - Assignees: KYOCERA Document Solutions Inc. - Inventors: Masaki HAYASHI; Yoshihiro YAMAGISHI; Hiroshi YAMAZAKI; Koji KURAMASHI; Eiji NIMURA - Web page: https://patentgrep.com/patent/US20130156468A1 ## CPC - G03G 15/0889: {for agitation or stirring} - G03G 15/0893: {in a closed loop within the sump of the developing device} - G03G: ELECTROGRAPHY; ELECTROPHOTOGRAPHY; MAGNETOGRAPHY ## Abstract A developing device includes a first agitating member and a second agitating member. Each of the first and second agitating members includes a screw having a helical portion formed helically so as to define a hollow portion, and a plurality of ribs formed on the helical portion in the longitudinal direction of the screw. On at least one of the first and second agitating members, there is disposed a paddle opposed to the communicating portion on a downstream side in a transport direction of the developing powder. The paddle has a flat surface in a direction perpendicular to the longitudinal direction, and a width of a distal end of the paddle is smaller than a width of a proximal end of the paddle disposed to the agitating member in a plan view. ## Claims ### Claim 1 A developing device comprising: a first transport path in which developing powder is transported in a predetermined direction; a second transport path in which the developing powder is transported in the opposite direction to the first transport path, extending in parallel and adjacent to the first transport path; a partition member which partitions between the first and second transport paths; communicating portions in which both ends in a longitudinal direction of the partition member are opened so that the developing powder can circulates in the first and second transport paths; a first agitating member disposed in the first transport path so as to agitate the developing powder and to transport the same in the first transport path in the longitudinal direction; and a second agitating member disposed in the second transport path so as to agitate the developing powder and to transport the same in the second transport path in the longitudinal direction, wherein each of the first and second agitating members includes a screw having a helical portion formed helically extending in each of the first and second transport paths in the longitudinal direction so as to define a hollow portion, and a plurality of ribs formed on the helical portion in the longitudinal direction of the screw, on at least one of the first and second agitating members, there is disposed a paddle opposed to the communicating portion on a downstream side in a transport direction of the developing powder, and the paddle has a flat surface in a direction perpendicular to the longitudinal direction, and a width of a distal end of the paddle is smaller than a width of a proximal end of the paddle disposed to the agitating member in a plan view. ### Claim 2 (depends on 1) The developing device according to claim 1, wherein the paddle is disposed to the agitating member rotating in a direction approaching from an upper side in the transport path to the partition member. ### Claim 3 (depends on 2) The developing device according to claim 2, wherein the first agitating member rotates in a direction approaching from a lower side in the first transport path to the partition member, the second agitating member rotates in a direction approaching from an upper side in the second transport path to the partition member, and the paddle is disposed to the second agitating member. ### Claim 4 (depends on 1) The developing device according to claim 1, wherein the paddle is formed in a trapezoidal shape in a plan view. ### Claim 5 (depends on 1) The developing device according to claim 1, wherein the paddle is formed in an arc shape in a plan view. ### Claim 6 (depends on 1) The developing device according to claim 1, wherein the paddle is formed in a triangular shape in a plan view. ### Claim 7 (depends on 1) The developing device according to claim 1, wherein each of the first and second agitating members further includes rotation shafts for being supported by the developing container at both end portions in the longitudinal direction in a rotatable manner, and flange portions having a rod-like shape extending in a radial direction of the rotation shaft so as to connect to the rib, and the paddle is formed on a link portion, which is disposed between the rotation shaft and the flange portion and is extending along the axial direction of the rotation shaft. ### Claim 8 (depends on 1) The developing device according to claim 1, wherein the paddle is formed of resin to which the developing powder hardly adheres. ### Claim 9 (depends on 1) The developing device according to claim 1, wherein the developing powder is single component magnetic developing powder. ### Claim 10 (depends on 1) An image forming apparatus comprising the developing device according to claim 1.