US 12,216,427 B2
Image forming apparatus having a pair of chains wound around a fixing roller and a transfer roller
Chihiro Iijima, Kanagawa (JP); Naohito Otsuki, Kanagawa (JP); Hiroyuki Suzuki, Kanagawa (JP); Yuta Chino, Kanagawa (JP); and Takehiko Koizumi, Kanagawa (JP)
Assigned to FUJIFILM Business Innovation Corp., Tokyo (JP)
Filed by FUJIFILM Business Innovation Corp., Tokyo (JP)
Filed on Jan. 25, 2022, as Appl. No. 17/583,574.
Claims priority of application No. 2021-137630 (JP), filed on Aug. 25, 2021.
Prior Publication US 2023/0066069 A1, Mar. 2, 2023
This patent is subject to a terminal disclaimer.
Int. Cl. G03G 15/00 (2006.01); B65H 5/08 (2006.01); B65H 29/04 (2006.01); G03G 15/20 (2006.01); G03G 15/16 (2006.01)
CPC G03G 15/6529 (2013.01) [B65H 5/085 (2013.01); B65H 29/044 (2013.01); G03G 15/2028 (2013.01); B65H 2301/44712 (2013.01); G03G 15/1615 (2013.01)] 15 Claims
OG exemplary drawing
 
5. An image forming apparatus comprising:
a fixing cylinder that is rotatably supported, that has a groove formed in an outer portion thereof in a rotational radial direction thereof, and that causes an image transferred to a recording medium to be fixed to the recording medium when the recording medium passes along an outer surface of the fixing cylinder in the rotational radial direction;
a delivery cylinder that is rotatably supported;
a circulating member that is loop-shaped and wrapped at least around the fixing cylinder and the delivery cylinder;
a plurality of holding members configured to hold the recording medium when the recording medium passes around the delivery cylinder toward the fixing cylinder, the holding members being supported by the circulating member such that the holding members are arranged in a length direction of the circulating member with predetermined intervals therebetween, each holding member being disposed in the groove when the holding member passes along the outer portion of the fixing cylinder; and
a pressure unit that is rotatably supported and that causes the recording medium to pass between the pressure unit and the fixing cylinder while a pressure is applied between the pressure unit and the fixing cylinder,
wherein Expression 1 is satisfied:
L2×n3−L8≥L4
where L2 is an interval in the length direction of the circulating member between one of the holding members and another one of the holding members that are adjacent to each other in the length direction of the circulating member,
L4 is a length of the circulating member in a region extending in a direction of travel of the circulating member from a rotationally upstream end portion of the groove in the fixing cylinder when the upstream end portion of the groove is in contact with the pressure unit to a position at which the recording medium is delivered to one of the holding members on the delivery cylinder,
n3 is number of the holding members disposed in the region from the rotationally upstream end portion of the groove in the fixing cylinder to the position at which the recording medium is delivered to one of the holding members on the delivery cylinder, and
L8 is ½ of a distance by which each holding member moves in a period from when the holding member starts a holding operation for holding the recording medium to when the holding operation is complete to hold the recording medium.