Patent ID: 11906924
Assignee: BROTHER KOGYO KABUSHIKI KAISHA
Field: Optics (Instruments)
Classification: CPC G | IPC B  G

Claim 7:
8. The image forming apparatus according to claim 1, further comprising:
a housing in which a conveyance path and a reconveyance path are formed, the conveyance path passing through the conveyance roller, the photosensitive drum, and the fuser, the reconveyance path being formed to guide the sheet having passed the fuser to a merge point where the reconveyance path joins the conveyance path, the merge point being located upstream of the conveyance roller in the sheet conveyance direction, the sensor being located downstream of the merge point in the sheet conveyance direction;
a discharge roller located downstream of the fuser in the sheet conveyance direction, the discharge roller being configured to discharge the sheet;
a post-registration sensor located downstream of the conveyance roller in the sheet conveyance direction; and
a discharge sensor located between the fuser and the discharge roller, the discharge sensor being configured to detect the sheet,
wherein residual position patterns of the sheet in the housing include:
a first residual position that is a residual position where the sheet is located between the post-registration sensor and the discharge sensor;
a second residual position that is a residual position where a leading edge of the sheet is detected by the sensor;
a third residual position that is a residual position where the leading edge of the sheet conveyed along the reconveyance path is located upstream of the sensor in the sheet conveyance direction and a trailing edge of the sheet conveyed along the reconveyance path is located away from the discharge roller;
a fourth residual position that is a residual position where the trailing edge of the sheet conveyed along the reconveyance path is nipped by the discharge roller while the discharge roller is rotating in a reconveyance direction; and
a fifth residual position that is a residual position where the sheet is nipped by the discharge roller while the discharge roller is rotating in the reconveyance direction; and

wherein, in the first mode process, the controller is configured to:
in response to determining that the sheet is located at the first residual position before the warm-up process is started, determine that a jam of the sheet occurs, stop the warm-up process, and output a notification prompting removal of the sheet at which the jam occurs;
in response to determining that the sheet is located at the second residual position before the warm-up process is started, determine that a jam of the sheet occurs, stop the warm-up process, and output a notification prompting removal of the sheet at which the jam occurs;
in response to determining that the sheet is located at a position within a particular distance from the sensor at the third residual position before the warm-up process is started, continue driving the photosensitive drum after the particular time elapses and discharge the sheet to the sheet discharge tray;
in response to determining that the sheet is located at the fourth residual position or at a position the particular distance away from the sensor at the third residual position before the warm-up process is started, determine that a jam of the sheet occurs, stop the warm-up process, and output a notification prompting removal of the sheet at which the jam occurs; and
in response to determining that the sheet is located at the fifth residual position before the warm-up process is started, control the discharge roller to discharge the sheet in a printing operation after the warm-up process is completed.