A post-processing unit includes a stapler, a driving section, and a controller. The stapler is moved in a Y direction and executes a stapling process on a paper sheet. The driving section moves the stapler in the Y direction. The controller controls an operation of the stapler and an operation of the driving section. The controller executes first control to supply a set current or a set voltage to the driving section, second control to supply, to the driving section, the same supply current as the set current or the same supply voltage as the set voltage, and third control to stop the supply of the supply current or the supply voltage. When the stapler executes the stapling process a plurality of times, the controller repeatedly executes the second control and the third control and causes the stapler to execute the stapling process during the execution of the second control.

A post-processing apparatus includes a paper alignment tray including a loading table on which a paper is to be loaded, and a side guide and an end guide to align a side in a width direction and an end in a longitudinal direction of the paper stack, respectively, a first binder including a binding unit to bind the paper stack on the paper alignment tray in a stapleless manner, the first binder displaceable to a binding location to bind the paper stack and to a separation location to separate the binding unit from the paper stack, and a controller to move the paper stack relative to the binding unit while displacing the first binder from the binding location to the separation location.

A post-processing apparatus includes a conveyor, a tray, a binder, and a binder mover. The conveyor conveys recording media on each of which an image is formed by an image forming apparatus. The tray holds the recording media conveyed by the conveyor. The binder binds the recording media on the tray with a plurality of staples in a cartridge. The binder mover includes a motor, a ratchet gear that receives a driving force of the motor to rotate in a forward direction or a reverse direction, a driving force transmitter that moves the binder toward one side in the main scanning direction as the ratchet gear rotates in the forward direction and moves the binder toward an opposite side in the main scanning direction as the ratchet gear rotates in the reverse direction, and a rotation limiter that moves between a rotation allowing position and a rotation limiting position.

A movable-member supporter includes: a first support member that includes a first support plate, a first guide unit provided at the first support plate, and a first connection section, the first guide unit guiding movement of a movable member and having one end that extends to one side surface of the first support plate, the first connection section being provided at the one side surface of the first support plate; and a second support member that includes a second support plate, a second guide unit provided at the second support plate, and a second connection section, the second guide unit guiding movement of the movable member and having one end that extends to one side surface of the second support plate, the second connection section being provided at the one side surface of the second support plate and being connected with the first connection section of the first support member.

A postprocessing apparatus includes: a first postprocessing member that performs postprocessing on a recording medium; a second postprocessing member that differs from the first postprocessing member and performs postprocessing on the recording medium; a mounting base to which the first and second postprocessing members are mounted; a support plate having a guide member that guides movement of the mounting base; and a moving mechanism that moves the mounting base along the guide member.

A post-processing device includes: a passage that extends in one direction; a post-processing section that is movable on a plane along the passage and that is stopped at plural post-processing positions, including a stop position determined in advance, to perform post-processing on a recording medium; and a positioning portion which is provided at the stop position and against which an end portion of the recording medium abuts when the post-processing section performs the post-processing at a post-processing position other than the stop position, the positioning portion being retracted with respect to the post-processing section when the post-processing section passes through the stop position or is moved toward the stop position.

A medium transport device includes a lower guide member, a processing tray, a feeding section, and a notch. The lower guide member supports a medium transported and guides the medium toward the processing tray. The processing tray includes an alignment member, and a plurality of media are stacked in the processing tray. The feeding section includes a paddle member having a rotation center between the processing tray and the lower guide member such that a rotation locus of a distal end intersects the lower guide member, and the feeding section is configured to feed the medium toward the alignment member. The lower guide member has a notch, and an upstream end of the notch in the transport direction is formed at a position inside the rotation locus in the lower guide member.

A sheet post-processing apparatus including a binding mechanism, a tray, a shift mechanism, and a control unit is provided. The binding mechanism is configured to apply binding to a sheet. The sheet applied with the binding is stacked on the tray. The shift mechanism is configured to perform a shift operation in which a side surface of the sheet is pushed and the sheet is deviated in a sheet width direction orthogonal to a discharge direction during discharge of the sheet to the tray. The control unit is configured to cause the shift operation to be performed by dividing the number of times for the shift operation into a plurality of times.

A recording material processing apparatus includes: first teeth that are used for binding processing of a recording material bundle; second teeth configured to move toward the first teeth and to press the recording material bundle positioned between the first teeth and the second teeth; a first metal block configured to support the first teeth; and a second metal block configured to support the second teeth.

A recording material processing apparatus includes first teeth that are used for binding processing of a recording material bundle; second teeth that move toward the first teeth and press the recording material bundle located between the first teeth and the second teeth; a guide portion that guides an interlocking portion interlocking with the second teeth; and a guided portion that is provided in the interlocking portion and guided by the guide portion, in which one of the guide portion and the guided portion includes a hole, and the other includes a rod-shaped portion that extends in a movement direction of the interlocking portion and comes into contact with an inner surface of the hole.