US 9,811,029 B2
Fixing device and image forming apparatus including the same
Haruyuki Honda, Kanagawa (JP); Ryuuichi Mimbu, Kanagawa (JP); Yoshio Hattori, Kanagawa (JP); Yoshiki Yamaguchi, Kanagawa (JP); and Toshihiko Shimokawa, Kanagawa (JP)
Assigned to Ricoh Company, Ltd., Tokyo (JP)
Filed by Haruyuki Honda, Kanagawa (JP); Ryuuichi Mimbu, Kanagawa (JP); Yoshio Hattori, Kanagawa (JP); Yoshiki Yamaguchi, Kanagawa (JP); and Toshihiko Shimokawa, Kanagawa (JP)
Filed on Mar. 18, 2016, as Appl. No. 15/73,800.
Claims priority of application No. 2015-058164 (JP), filed on Mar. 20, 2015.
Prior Publication US 2016/0274509 A1, Sep. 22, 2016
Int. Cl. G03G 15/20 (2006.01); G03G 15/00 (2006.01)
CPC G03G 15/2028 (2013.01) [G03G 15/6576 (2013.01); G03G 2215/00662 (2013.01); G03G 2215/0132 (2013.01); G03G 2215/2035 (2013.01)] 8 Claims
OG exemplary drawing
 
1. A fixing device comprising:
a flexible endless fixing member;
a heater to heat the fixing member;
a nip forming member to contact the fixing member directly or via a slide member;
a pressure member, rotatably disposed opposite the fixing member and the nip forming member, to press the fixing member to thereby form a fixing nip portion together with the nip forming member, wherein the fixing device fixes an image in the fixing nip portion with heat and pressure onto a recording sheet;
a back curl correction structure disposed downstream of and adjacent to the fixing nip portion in a recording sheet feeding direction,
the back curl correction structure including:
a drive roller disposed on a side where a back curl appears in the recording sheet;
a driven roller disposed opposite the drive roller;
an auxiliary nip portion between the drive roller and the driven roller to feed the recording sheet; and
a guide member disposed at the same side as the drive roller relative to the auxiliary nip portion to guide the recording sheet fed out from the auxiliary nip portion to bend in a direction opposite a curled direction of the back curl of the recording sheet,
a drive roller side connection gear to input a rotary driving force to a rotary shaft of the drive roller; and
a pressure member side connection gear to branch and output the rotary driving force of the pressure member, a driving connection between the drive roller and the pressure member being performed by a connection between the drive roller side connection gear and the pressure member side connection gear;
wherein the pressure member includes a release structure to shift the nip forming member and the fixing member between a pressurized state and a released state in which the pressurized state is relaxed, and
wherein the driving connection between the drive roller and the pressure member is released when the pressure member is released, by separation between the pressure member side connection gear and the drive roller side connection gear.