US 12,271,125 B2
Developing device and image forming apparatus provided therewith
Ryo Yamada, Osaka (JP)
Assigned to KYOCERA Document Solutions Inc., Osaka (JP)
Appl. No. 18/565,738
Filed by KYOCERA Document Solutions Inc., Osaka (JP)
PCT Filed Mar. 28, 2022, PCT No. PCT/JP2022/014853
§ 371(c)(1), (2) Date Nov. 30, 2023,
PCT Pub. No. WO2022/254915, PCT Pub. Date Dec. 8, 2022.
Claims priority of application No. 2021-094278 (JP), filed on Jun. 4, 2021; and application No. 2021-153947 (JP), filed on Sep. 22, 2021.
Prior Publication US 2024/0255867 A1, Aug. 1, 2024
Int. Cl. G03G 15/08 (2006.01); B01D 39/16 (2006.01); G03G 21/20 (2006.01)
CPC G03G 15/0891 (2013.01) [B01D 39/16 (2013.01); G03G 15/0898 (2013.01); G03G 21/206 (2013.01)] 14 Claims
OG exemplary drawing
 
1. A developing device, comprising:
a development container that includes a first conveyance chamber, a second conveyance chamber that is disposed side by side with the first conveyance chamber with a partition portion therebetween, and a communication portion that establishes communication between the first conveyance chamber and the second conveyance chamber at opposite end part sides of the partition portion in a longitudinal direction thereof, and that stores a developer including a toner;
a first stirring conveyance member that includes a first rotation shaft rotatably supported in the first conveyance chamber and a first stirring blade formed on an outer circumferential surface of the first rotation shaft, and that stirs and conveys the developer in the first conveyance chamber;
a second stirring conveyance member that includes a second rotation shaft rotatably supported in the second conveyance chamber and a second stirring blade formed on an outer circumferential surface of the second rotation shaft, and that stirs and conveys the developer in the second conveyance chamber; and
a developer carrier that is opposed to the second stirring conveyance member, and that carries on a surface thereof the toner in the second conveyance chamber,
wherein
the first rotation shaft includes: a tapered portion that is provided in a region, with respect to a developer conveyance direction, from an upstream-side end part to a central part of the first rotation shaft, and of which a shaft diameter increases toward a downstream side in the developer conveyance direction in the first conveyance chamber; and a straight portion that is provided in a region, with respect to the developer conveyance direction, from a downstream-side end part of the tapered portion to a downstream-side end part of the first rotation shaft, and of which a shaft diameter is equal to a shaft diameter of the downstream-side end part of the tapered portion,
the development container includes a toner supply path that communicates with an outside of the development container, and that communicates with the first conveyance chamber from an upstream side of the first conveyance chamber with respect to the developer conveyance direction,
the first conveyance member includes a supply blade that is formed on the outer circumferential surface of such part of the first rotation shaft as extends inside the toner supply path, and that conveys the toner in the toner supply path into the first conveyance chamber, and
an amount of the toner conveyed by the supply blade per pitch is smaller than an amount of the developer conveyed by such part of the first stirring blade as is located at an upstream-side end part of the tapered portion in the developer conveyance direction per pitch.