A medium conveying apparatus includes a first optical sensor located on an upper part of the housing and in a central part of the housing in a direction perpendicular to a medium conveying direction, a second optical sensor located on an upper part of the housing and on a side of the first optical sensor in the direction perpendicular to the medium conveying direction, and a processor to detect a folding of a medium based on the first signal or the second signal, and stop feeding of the medium by the feed roller in accordance with a detection result of the folding of the medium. The first light emitter emits first light toward a downstream side of the medium in the medium conveying direction, and the second light emitter emits second light toward an upstream side of the medium in the medium conveying direction.

A medium conveying apparatus includes a first optical sensor located on an upper part of the housing and in a central part of the housing in a direction perpendicular to a medium conveying direction, a second optical sensor located on an upper part of the housing and on a side of the first optical sensor in the direction perpendicular to the medium conveying direction, and a processor to detect a folding of a medium based on the first signal or the second signal, and stop feeding of the medium by the feed roller in accordance with a detection result of the folding of the medium. The first light emitter emits first light toward a downstream side of the medium in the medium conveying direction, and the second light emitter emits second light toward an upstream side of the medium in the medium conveying direction.

A medium-transporting device includes: a medium-mounting section on which a medium is mounted; a feeding unit that includes a feeding roller and that is configured to be displaced between a contact posture and a separation posture; a first restricting member that is provided downstream of the feeding roller in the transport direction and that is configured to switch between a restriction posture in which the first restricting member restricts movement of the medium and a retreat posture in which the first restricting member permits the movement of the medium; a first motor configured to generate power for rotating the feeding roller; and a second motor configured to generate power for switching a posture of the first restricting member, in which an operation of rotating the feeding roller and an operation of switching the first restricting member from the restriction posture to the retreat posture are performed in parallel.

A power transmission apparatus includes a drive source, a power transmission switching section configured to switch between a transmission state in which power of the drive source is transmitted to a driven section and a non-transmission state in which power of the drive source is not transmitted to the driven section, a load switching section configured to switch between a first load state, which is a load while the driven section is driven, and a second load state, which is a load smaller than the load of the first load state, and a control section, wherein the control section switches the power transmission switching section from the non-transmission state to the transmission state while the load is in the second load state, and then uses the load switching section to switch the load from the second load state to the first load state.

A reading apparatus to convey a document set on a document tray and to read an image of the conveyed document includes a control unit and a determining unit. The control unit performs lifting control for lifting the document tray in a case where a first condition is satisfied and performs lowering control for lowering the document tray in a case where a second condition is satisfied. The determining unit determines whether a predetermined period elapses after the lifting control of previous time is started. The control unit does not perform the lowering control even if the second condition is satisfied in a case where the determining unit determines that the predetermined period does not elapse.

A medium conveying apparatus includes a conveyance roller to convey a medium, an imaging device to image the medium, a DC motor to drive the conveyance roller, a processor to detect that a front end of the medium reaches between the conveyance roller and the imaging device, set a current limit value of the DC motor to a first limit value until the front end of the medium reaches between the conveyance roller and the imaging device, and change the current limit value to a second limit value larger than the first limit value after the front end of the medium has reached between the conveyance roller and the imaging device, and drive the conveyance roller by rotating the DC motor based on the second limit value when the imaging device performs imaging.

A post-processing apparatus according to an embodiment includes a processing tray, a post-processing section, a sensor, and a control section. A sheet supplied from an image forming apparatus is led into the processing tray through a lead-in path. The post-processing section applies post-processing to the sheet sent from the processing tray. The sensor detects an object passing a detection space in the lead-in path. The control section controls operation of the post-processing section based on a time in which the sensor detects the object.

A post-processing apparatus according to an embodiment includes a processing tray, a post-processing section, a sensor, and a control section. A sheet supplied from an image forming apparatus is led into the processing tray through a lead-in path. The post-processing section applies post-processing to the sheet sent from the processing tray. The sensor detects an object passing a detection space in the lead-in path. The control section controls operation of the post-processing section based on a time in which the sensor detects the object.

A document conveying device includes a document tray, a first rotary member, a first motor, a second rotary member, a second motor, a document feed sensor, and a controller. The controller counts a counted time from the time point that the first motor starts to rotate until the leading end of a document reaches the document feed sensor. When the time resulting from subtracting the counted time from a required sheet-to-sheet time interval is longer than the required speed change time, the controller performs deceleration and post-deceleration acceleration for the first motor. The required speed change time is the time required for speed change from the first rotation speed to the second rotation speed.

An image forming system includes an image forming apparatus, a first conveyance path, a sheet feeding unit, a sheet post-processing unit, and a controller. The image forming apparatus has a first feed portion, and an image forming portion. The sheet feeding apparatus has a sheet stacking portion, a second feed portion, a relay conveyance portion, and a remaining amount detecting portion. When, during continuous printing, the existing number of recording sheets present in a conveyance passage from a confluence portion to the first feed portion is more than the constituting number of recording sheets contained in one bundle of sheets and in addition the sensing result of the remaining amount sensor is equal to or less than a predetermined amount, the controller controls first feed portion such that the existing number of the recording sheets is less than the constituting number of recording sheets.