US 12,443,131 B2
Image forming apparatus having transfer member with specific resistance
Naohiro Kumagai, Kanagawa (JP); Yuusuke Furuichi, Kanagawa (JP); and Daisuke Hirano, Kanagawa (JP)
Assigned to Ricoh Company, Ltd., Tokyo (JP)
Appl. No. 18/836,218
Filed by Naohiro Kumagai, Kanagawa (JP); Yuusuke Furuichi, Kanagawa (JP); and Daisuke Hirano, Kanagawa (JP)
PCT Filed Mar. 2, 2023, PCT No. PCT/IB2023/051925
§ 371(c)(1), (2) Date Aug. 6, 2024,
PCT Pub. No. WO2023/175426, PCT Pub. Date Sep. 21, 2023.
Claims priority of application No. 2022-044148 (JP), filed on Mar. 18, 2022.
Prior Publication US 2025/0044727 A1, Feb. 6, 2025
Int. Cl. G03G 15/16 (2006.01)
CPC G03G 15/1685 (2013.01) [G03G 15/167 (2013.01); G03G 2215/1614 (2013.01)] 5 Claims
OG exemplary drawing
 
1. An image forming apparatus comprising:
a fixing device including:
a rotatable fixing belt configured to be grounded via a first grounding path from the fixing belt to a ground, the first grounding path including a protective resistor;
a heater configured to be in contact with an inner circumferential surface of the fixing belt; and
a pressure rotator facing the fixing belt to form a fixing nip, the pressure rotator configured to be grounded via a second grounding path;
a power supply configured to apply an alternating current voltage to the heater; and
a transfer device upstream from the fixing device in a recording medium conveyance direction of a recording medium,
the transfer device including:
a rotatable transferor configured to be grounded via a third grounding path; and
an opposed rotator facing the transferor to form a transfer nip,
the transferor having a transferor resistance satisfying a following expression,

OG Complex Work Unit Math
where Rt is a resistance value of the transferor resistance, Rf is a grounding resistance value of the protective resistor, Rp is a resistance value of the recording medium, jXs is an impedance of the fixing belt, and jXh is an impedance of the heater.