Medium processing apparatus and image forming system incorporating same

A medium processing apparatus comprising:

• a liquid applier to apply liquid to a part of at least one medium conveyed in a conveyance direction;
• a binder adjacent to the liquid applier in a main scanning direction orthogonal to the conveyance direction to perform a given process on a bundle of media including the at least one medium on which the liquid is applied by the liquid applier;
• a mover to cause the liquid applier and the binder to move between a first side and a second side in the main scanning direction along a surface of the at least one medium;
• a first rotator to rotate the binder about a first shaft to change a posture of the binder between:
• a first inclined posture in which a lateral direction of the binder is inclined to the main scanning direction;
• and
• a first parallel posture in which the lateral direction of the binder is parallel to the main scanning direction;
• and
• a second rotator to rotate the liquid applier about a second shaft to change a posture of the liquid applier between:
• a second inclined posture in which a lateral direction of the liquid applier is inclined to the main scanning direction;
• and
• a second parallel posture in which the lateral direction of the liquid applier is parallel to the main scanning direction,
• wherein the second rotator includes:
• a posture change assembly to:
• change the posture of the liquid applier from the second inclined posture to the second parallel posture at a posture changing position when the liquid applier moves toward the first side in the main scanning direction;
• and
• change the posture of the liquid applier from the second parallel posture to the second inclined posture at the posture changing position when the liquid applier moves toward the second side;
• and
• a collision avoidance assembly to:
• allow the binder in the first inclined posture to pass a restriction position;
• and
• restrict the binder in the first parallel posture from passing through the restriction position, and
• the binder reaches the restriction position before the liquid applier reaches the posture changing position.