US 11,681,242 B2
Developing device and image forming apparatus having a reverse helical section
Shota Igawa, Kanagawa (JP); Masanori Kato, Kanagawa (JP); Katsumi Yamada, Kanagawa (JP); Yoshihisa Nakao, Kanagawa (JP); Atsushi Funada, Kanagawa (JP); and Mitsutoshi Hongo, Kanagawa (JP)
Assigned to FUJIFILM Business Innovation Corp., Tokyo (JP)
Filed by FUJIFILM Business Innovation Corp., Tokyo (JP)
Filed on Aug. 20, 2021, as Appl. No. 17/407,270.
Claims priority of application No. JP2021-085637 (JP), filed on May 20, 2021.
Prior Publication US 2022/0373930 A1, Nov. 24, 2022
Int. Cl. G03G 15/08 (2006.01)
CPC G03G 15/0891 (2013.01) [G03G 15/0844 (2013.01); G03G 15/0893 (2013.01); G03G 2215/083 (2013.01); G03G 2215/0822 (2013.01)] 9 Claims
OG exemplary drawing
 
1. A developing device comprising:
a first transport member and a second transport member that are disposed, respectively, in a first transport path and a second transport path provided at an upper side and a lower side in a gravitational direction and that are configured to transport a developer so as to cause the developer to circulate between the first transport path and the second transport path;
an ejecting path that is provided in the first transport path, wherein the ejecting path is disposed at the upper side in the gravitational direction and is configured to eject an excess developer; and
a reverse helical section that is disposed on a side of a support that supports the second transport member, the reverse helical section helically extending in a reverse direction relative to a helical section provided for circulating the developer, and the side of the support being upstream from the support in the reverse direction,
wherein the reverse helical section is disposed in the second transport path,
wherein the reverse helical section is configured to transport the developer to the ejecting path,
wherein the developing device further comprises an auxiliary helical section that is provided between the support and the reverse helical section, the auxiliary helical section helically extending in a helical direction identical to that of the reverse helical section, and
wherein the auxiliary helical section has a diameter smaller than that of the reverse helical section.