An image forming apparatus has a sheet feed portion, a conveying portion, a control portion, a first sensor having the detection position at a first position in the sheet conveying passage, and a second sensor having the detection position at a second position downstream of the first position in the sheet conveying direction. The control portion performs first sensing to sense whether the sheet's rear end has passed the first position within a first time of the start of the feeding and second sensing to sense whether the sheet's rear end has passed the second position within a second time of the start of the feeding. Even if the control portion is unable to sense passage of the sheet's rear end in the first sensing, when it senses passage of the sheet's rear end in the second sensing, it makes the conveying portion continue feeding the sheet.

An image forming apparatus includes an image forming unit, a storage portion to which a heating unit configured to heat the sheet stored in the storage portion is detachably attached, a conveyance unit, a detection unit configured to detect attachment of the heating unit to the storage portion, and a control unit configured to control the conveyance unit such that a standby time by which conveyance of the sheet fed from the storage portion is stopped is shorter when the detection unit detects the heating unit than when the detection unit does not detect the heating unit.

A sheet processing device includes a post-processing unit, a process tray, a first sensor, a second sensor, and a control unit. The post-processing unit performs post-processing on the sheet. The process tray places the sheet to be post-processed on the upper surface. The first sensor is disposed on the upper side of the process tray. The first sensor outputs a first signal corresponding to a first distance to an object which is disposed at a first position of the process tray. The second sensor is disposed on the upper side of the process tray. The second sensor outputs a second signal corresponding to a second distance to the object which is disposed at a second position on the downstream side in a sheet discharge direction from the first position of the process tray. The control unit controls the post-processing using the first signal and the second signal.

A sheet processing device includes a post-processing unit, a process tray, a first sensor, a second sensor, and a control unit. The post-processing unit performs post-processing on the sheet. The process tray places the sheet to be post-processed on the upper surface. The first sensor is disposed on the upper side of the process tray. The first sensor outputs a first signal corresponding to a first distance to an object which is disposed at a first position of the process tray. The second sensor is disposed on the upper side of the process tray. The second sensor outputs a second signal corresponding to a second distance to the object which is disposed at a second position on the downstream side in a sheet discharge direction from the first position of the process tray. The control unit controls the post-processing using the first signal and the second signal.

A printing apparatus comprises: a conveyance unit configured to convey a sheet to a printing unit configured to perform printing; a control unit configured to cause the conveyance unit to hold the sheet onto which printing was performed by the printing unit; and a receiving unit configured to receive an ejection instruction for instructing to eject the sheet, wherein the control unit, in a case where the receiving unit receives the ejection instruction, controls the conveyance unit to eject the sheet to outside of the apparatus after a predetermined time has elapsed.

A controller starts sheet feeding at a primary sheet feeding speed, then momentarily stops a sheet feeding rotary member, and thereafter starts secondary sheet feeding. When the secondary sheet feeding speed equals a first speed, the controller momentarily stops the sheet feeding rotary member such that the leading end of a document sheet stops at a first stop position. When the secondary sheet feeding speed equals a second speed, the controller momentarily stops the sheet feeding rotary member such that the leading end of a document sheet stops at a second stop position. The second stop position is located downstream of the first stop position in the document conveying direction.

A paper conveying device, used in a paper processing device to perform predetermined processing on paper, includes a conveying portion, a holding portion, a detection portion, and a control portion. The conveying portion conveys, in a conveying direction, the paper to a processing portion of the paper processing device. The holding portion is disposed downstream of the processing portion in the conveying direction and holds the paper processed by the paper processing device. The detection portion detects a change of an orientation of the paper held by the holding portion. The control portion releases the paper held by the holding portion in a case where an amount of the detected orientation change reaches a predetermined amount.

A paper conveying device, used in a paper processing device to perform predetermined processing on paper, includes a conveying portion, a holding portion, a detection portion, and a control portion. The conveying portion conveys, in a conveying direction, the paper to a processing portion of the paper processing device. The holding portion is disposed downstream of the processing portion in the conveying direction and holds the paper processed by the paper processing device. The detection portion detects a change of an orientation of the paper held by the holding portion. The control portion releases the paper held by the holding portion in a case where an amount of the detected orientation change reaches a predetermined amount.

According to one embodiment, a post-processing apparatus includes a first sensor, a second sensor, and a control unit. The first sensor detects an object in a predetermined area in which a predetermined post-process is performed on a sheet conveyed from an image forming apparatus. The second sensor detects an object at a position closer to an opening in the area than the position of the first sensor with respect to the opening through which the sheet passes when the post-processed sheet is discharged from the area. When the second sensor detects an object before the first sensor detects the object, the control unit performs a predetermined process for preventing the occurrence of a failure.

According to one embodiment, a post-processing apparatus includes a first sensor, a second sensor, and a control unit. The first sensor detects an object in a predetermined area in which a predetermined post-process is performed on a sheet conveyed from an image forming apparatus. The second sensor detects an object at a position closer to an opening in the area than the position of the first sensor with respect to the opening through which the sheet passes when the post-processed sheet is discharged from the area. When the second sensor detects an object before the first sensor detects the object, the control unit performs a predetermined process for preventing the occurrence of a failure.