US 10,890,872 B2
Image forming apparatus
Ryou Sakaguchi, Toride (JP); Tadao Sugiura, Moriya (JP); Naoko Mima, Moriya (JP); Shun Motohashi, Misato (JP); and Masashi Yokoyama, Saitama (JP)
Assigned to Canon Kabushiki Kaisha, Tokyo (JP)
Filed by CANON KABUSHIKI KAISHA, Tokyo (JP)
Filed on Oct. 4, 2018, as Appl. No. 16/151,824.
Claims priority of application No. 2017-198316 (JP), filed on Oct. 12, 2017.
Prior Publication US 2019/0113878 A1, Apr. 18, 2019
Int. Cl. G03G 15/00 (2006.01); G03G 15/16 (2006.01); G03G 15/01 (2006.01)
CPC G03G 15/70 (2013.01) [G03G 15/0136 (2013.01); G03G 15/1615 (2013.01); G03G 15/5062 (2013.01); G03G 15/6529 (2013.01)] 9 Claims
OG exemplary drawing
 
1. An image forming apparatus, comprising:
a storage unit configured to store a recording medium;
a feeding unit configured to feed the recording medium from the storage unit;
a first photosensitive drum on which a color toner image is to be formed;
a second photosensitive drum on which a black toner image is to be formed;
an intermediate transfer member to which the color toner image and the black toner image are to be transferred;
a transfer portion configured to transfer the toner images having been transferred on the intermediate transfer member to the recording medium;
a mechanism configured to bring the intermediate transfer member into a first state in which the intermediate transfer member is in contact with the first photosensitive drum and the second photosensitive drum and a second state in which the intermediate transfer member is separated from the first photosensitive drum and in contact with the second photosensitive drum;
a detector configured to detect the recording medium fed by the feeding unit; and
a controller,
wherein the image forming apparatus is operable in:
a first image forming mode of bringing the intermediate transfer member into the first state and forming an image by using the first photosensitive drum and the second photosensitive drum;
a second image forming mode of bringing the intermediate transfer member into the second state and forming an image by using only the second photosensitive drum; and
a third image forming mode of bringing the intermediate transfer member into the first state and forming an image by using only the second photosensitive drum, and
wherein the controller is configured to:
determine an occurrence of a recording medium conveyance delay in which a recording medium is not detected by the detector within a predetermined time period;
in a case in which the recording medium conveyance delay occurs, perform restarting a feeding operation by the feeding unit and perform an image forming retry involving an operation of cleaning the transfer portion; and
in a case in which the image forming retry is to be performed in the third image forming mode, change over the third image forming mode to the second image forming mode without stopping rotation of the second photosensitive drum and perform an image formation on a recording medium fed by restart of the feeding operation after the third image forming mode is changed over to the second image forming mode.