A sheet stacking device include a guide unit and a blower. The guide unit receives a downstream end of a sheet in a sheet conveyance direction and guides the sheet downstream in the sheet conveyance direction. The blower blows air toward the sheet guided by the guide unit. A region of the blower from which the air is blown is changeable in response to a size of the sheet.

A medium transport device includes a feeding unit that transports a medium, a stack portion that receives the medium transported by the feeding unit between a support surface for supporting the medium in an inclined posture in which a downstream side in a transport direction is directed downward and an opposing surface opposing the support surface and stacks the medium, an alignment portion that aligns a downstream end of the medium stacked in the stack portion, a paddle that is provided between the feeding unit and the alignment portion in the transport direction and moves the medium toward the alignment portion by rotating while being in contact with the medium, and a control unit that controls an operation of the paddle, in which the control unit controls the operation of the paddle according to a condition.

A medium transport device includes a feeding unit that transports a medium, a stack portion that receives the medium transported by the feeding unit between a support surface for supporting the medium in an inclined posture in which a downstream side in a transport direction is directed downward and an opposing surface opposing the support surface and stacks the medium, an alignment portion that aligns a downstream end of the medium stacked in the stack portion, a paddle that is provided between the feeding unit and the alignment portion in the transport direction and moves the medium toward the alignment portion by rotating while being in contact with the medium, and a control unit that controls an operation of the paddle, in which the control unit controls the operation of the paddle according to a condition.

Provided is a paper sheet loading device including a paper sheet loading unit having a bottom plate and a front wall, a feed roller that comes in contact with a bottom surface of a lowermost paper sheet of a batch of paper sheets and rotates to feed the lowermost paper sheet to outside of the paper sheet loading unit, and a load adjusting member arranged so as to protrude into the paper sheet loading unit and retreat to outside of the paper sheet loading unit. At a time of protrusion of the load adjusting member, the load adjusting member presses a front side face of the batch of paper sheets by a pressing surface to displace the front side face to an innermost part, and receives a load from the batch of paper sheets by the pressing surface, thereby reducing the load applied to the feed roller from the batch of paper sheets.

Provided is a paper sheet loading device including a paper sheet loading unit having a bottom plate and a front wall, a feed roller that comes in contact with a bottom surface of a lowermost paper sheet of a batch of paper sheets and rotates to feed the lowermost paper sheet to outside of the paper sheet loading unit, and a load adjusting member arranged so as to protrude into the paper sheet loading unit and retreat to outside of the paper sheet loading unit. At a time of protrusion of the load adjusting member, the load adjusting member presses a front side face of the batch of paper sheets by a pressing surface to displace the front side face to an innermost part, and receives a load from the batch of paper sheets by the pressing surface, thereby reducing the load applied to the feed roller from the batch of paper sheets.

Provided are a post-processing apparatus, an image forming apparatus, and a post-processing method capable of avoiding the occurrence of a malfunction due to a failure to discharge a sheet bundle after a binding process. A plurality of sheets is loaded on a stack tray. A staple unit binds the plurality of sheets. A discharge roller discharges the sheet bundle bound by the staple unit from the stack tray. Each time a sheet is conveyed to the stack tray, an aligning unit moves between a first position in contact with the sheet loaded on the stack tray and a second position separating from the sheet. A detection processing unit detects a failure of discharging the sheet bundle by the discharging roller. A stop processing unit can stop the operation of the aligning unit when the discharge failure is detected by the detection processing unit.

Provided are a post-processing apparatus, an image forming apparatus, and a post-processing method capable of avoiding the occurrence of a malfunction due to a failure to discharge a sheet bundle after a binding process. A plurality of sheets is loaded on a stack tray. A staple unit binds the plurality of sheets. A discharge roller discharges the sheet bundle bound by the staple unit from the stack tray. Each time a sheet is conveyed to the stack tray, an aligning unit moves between a first position in contact with the sheet loaded on the stack tray and a second position separating from the sheet. A detection processing unit detects a failure of discharging the sheet bundle by the discharging roller. A stop processing unit can stop the operation of the aligning unit when the discharge failure is detected by the detection processing unit.

A method of measuring properties of a moving cellulose, paper or board sheet. A first parameter of a first resonance caused by the moving sheet in a frequency range 1 GHz to 25 GHz of electromagnetic radiation is measured. A second parameter of an electromagnetic signal transmitted between at least a pair of transceiver parts of a transceiver sensor located on opposite sides of the moving sheet through the moving sheet is measured in a frequency range 25 GHz to 1000 GHz. A minimum difference between the frequency ranges related to the first parameter and the second parameter being at least 5 GHz. Both the dry stuff content and the weight of water per unit of area are determined on the basis of the first parameter, the second parameter and available information related to a distance travelled by the electromagnetic signal.

In a copier, printer, or similar device, paper is loaded in large quantities. To separate a top sheet of a stack of sheets from the next adjacent sheet, a dam is used, which is an element having an inclined surface in the path of the top sheet. This invention addresses devices with variably compliant separation strips, preferably a thermoplastic polyurethane elastomer such as Pellethane®, that are part of the dam, so that the leading edge of a media sheet will strike the inclined surface of the separation strip. By adjusting the compliance of the separation strip, different weights of media may be accommodated while minimizing the multi-feeds that may cause jamming of the device.

A recording medium conveyance device includes a storage, a conveyer that conveys a conveyed object, an ultrasonic sensor that outputs a value indicating an attenuation amount of an ultrasonic wave caused by the conveyed object, and a hardware processor. The hardware processor executes a type detection process of detecting a type of the conveyed object based on output of the ultrasonic sensor and storing the type in the storage and an overlay detection process of detecting whether the conveyed object is in an overlay state in which a gap is present based on output of the ultrasonic sensor, and switches to either one of the type detection process and the overlay detection process. The hardware processor executes the type detection process when the type is not stored in the storage and executes the overlay detection process when the type is stored in the storage.