A printing apparatus includes a feeding roller configured to feed a printing sheet stacked on a stacking unit, a conveyance roller configured to convey the printing sheet fed by the feeding roller, a printing unit configured to print the printing sheet conveyed by the conveyance roller, a conveyance control unit configured to control conveyance of printing sheets so that the trailing edge of a preceding sheet as a printing sheet precedingly fed from the stacking unit and the leading edge of a succeeding sheet as a printing sheet succeedingly fed from the stacking unit overlap each other, and a determination unit configured to determine whether to convey the succeeding sheet to a position facing the printing unit while keeping an overlap state between the preceding sheet and the succeeding sheet.

A document feeding device includes a feeding unit feeding documents from a batch of documents on a placing tray, a separation member in pressure contact with the feeding unit and separating documents one by one, a separation swinging member supporting the separation member and displaceable in a thickness direction of the batch of documents, and a movable member supported as to be displaceable with respect to the separation swing member in the thickness direction of the batch of documents, and entering a space formed between the separation member and a document.

A document feeding device includes a feeding unit feeding documents from a batch of documents on a placing tray, a separation member in pressure contact with the feeding unit and separating documents one by one, a separation swinging member supporting the separation member and displaceable in a thickness direction of the batch of documents, and a movable member supported as to be displaceable with respect to the separation swing member in the thickness direction of the batch of documents, and entering a space formed between the separation member and a document.

A sheet feeding apparatus includes a sheet stacker to stack at least one sheet; a sheet feed roller disposed at one side of the sheet stacker and to feed a sheet fed from the sheet stacker; a multi-feed prevention roller disposed to face the sheet feed roller and to prevent multi-feed of the sheet fed from the sheet stacker; a magnetic torque limiter disposed coaxially with the multi-feed prevention roller; a hall sensor disposed at one side of the magnetic torque limiter and to detect rotation of the magnetic torque limiter; and a controller configured to rotate the sheet feed roller in a state in which the sheet feed roller and the multi-feed prevention roller are in contact with each other without a sheet and to identify a lifetime of the multi-feed prevention roller by using a signal output from the hall sensor.

A sheet feeding apparatus includes a sheet stacker to stack at least one sheet; a sheet feed roller disposed at one side of the sheet stacker and to feed a sheet fed from the sheet stacker; a multi-feed prevention roller disposed to face the sheet feed roller and to prevent multi-feed of the sheet fed from the sheet stacker; a magnetic torque limiter disposed coaxially with the multi-feed prevention roller; a hall sensor disposed at one side of the magnetic torque limiter and to detect rotation of the magnetic torque limiter; and a controller configured to rotate the sheet feed roller in a state in which the sheet feed roller and the multi-feed prevention roller are in contact with each other without a sheet and to identify a lifetime of the multi-feed prevention roller by using a signal output from the hall sensor.

An image forming apparatus includes a first detection unit, a second detection unit, a first conveyance unit, a second conveyance unit, which is provided on downstream in the conveyance direction with respect to the first detection unit and is configured to convey sheets, and a control unit. When the first detection unit does not detect a trailing edge of a first sheet before a first timing, the control unit stops the drive of the first conveyance unit and continues drive of the second conveyance unit, and when the second detection unit detects the trailing edge of the first sheet before a second timing later than the first timing, the control unit re-drives the first conveyance unit or stops the drive of the second conveyance unit in accordance with a sheet length of the first sheet in the conveyance direction.

An image forming apparatus includes a first detection unit, a second detection unit, a first conveyance unit, a second conveyance unit, which is provided on downstream in the conveyance direction with respect to the first detection unit and is configured to convey sheets, and a control unit. When the first detection unit does not detect a trailing edge of a first sheet before a first timing, the control unit stops the drive of the first conveyance unit and continues drive of the second conveyance unit, and when the second detection unit detects the trailing edge of the first sheet before a second timing later than the first timing, the control unit re-drives the first conveyance unit or stops the drive of the second conveyance unit in accordance with a sheet length of the first sheet in the conveyance direction.

A paper conveyance device includes a paper feed unit, a conveyance rotator, a conveyance guide, a multi-feed detection unit, and a control unit. The control unit causes an ultrasonic sensor to transmit an ultrasonic wave in a detection section. The control unit sets a detection execution section and a detection skip section in the detection section. The control unit does not determine whether multi-feed has occurred in the detection skip section. The control unit sets the detection skip section based on a time point at which vibration is applied to conveyed paper.

A sheet transport device includes a processor configured to adjust movement of a transport unit that transports a sheet on the basis of a transport load of the sheet.

A sheet transport device includes a processor configured to adjust movement of a transport unit that transports a sheet on the basis of a transport load of the sheet.