An image forming system includes: an image forming apparatus that forms an image on a sheet; and a post-processor including a punch unit that forms a punch hole on the sheet conveyed from the image forming apparatus, wherein the image forming apparatus includes a conveyance control part that controls conveyance of the sheet to be conveyed to the post-processor, and the punch unit includes: a perforating part that forms the punch hole on the sheet; a detection part that performs sheet side end portion detection for detecting a side end portion in a main scanning direction, and paper dust detection for detecting a paper dust amount in a detection region; a swinging part that moves the perforating part to an arbitrary position; and a hardware processor that, when a punch job is performed, controls the detection part to perform the paper dust detection.

A sheet processing apparatus includes a first conveyance rotary member, a second conveyance rotary member, a punch member, a sensor, a punch motor, a conveyance motor, a first drive transmission portion including a first number of drive transmission members configured to sequentially transmit driving force of the conveyance motor to the first conveyance rotary member, and a second drive transmission portion including a second number of drive transmission members configured to sequentially transmit driving force of the conveyance motor to the second conveyance rotary member, the second number being larger than the first number.

A post-processing apparatus to perform a post-processing for a sheet conveyed from an image forming apparatus includes a punching unit, first and second motors, and a control unit. The punching unit includes a punch that is rotated by the first motor to punch the sheet, and a moving unit moved by the second motor to move the punch in a width direction intersecting with a sheet conveying direction. The control unit controls at least the first motor. In a first section from a first position in which the punch starts punching the sheet to a second position in which the punching ends, the control unit sets a current value for driving the first motor to a first current value. In a second section other than the first section, the control unit can set the first motor driving current value to a second current value lower than the first current value.

A printing system is disclosed. The printing system includes a printing unit, a sheet processing unit, and a control unit. The sheet processing unit performs a designated sheet process for the printed sheet using a die that is manually selected by a user and attached to the sheet processing unit. When the die for performing the designated sheet process is not attached to the sheet processing unit, it is determined, before the printing unit starts printing the image on a first sheet on which the printing unit prints the image firstly among sheets on which the designated sheet process is to be performed, not to perform the designated sheet process for the sheets on which the designated sheet process is to be performed. The printing unit starts printing the image on the sheets on which the designated sheet process is to be performed after the determination.

A post processing apparatus includes: a reader that reads paper on which an image is formed by an image forming apparatus to acquire a read image; a post processor that performs post processing on the paper; and a hardware processor that detects a position of an edge of the paper and a position of the image from the read image acquired by the reader, and controls a post processing position in the post processor on the basis of the position of the edge of the paper and the position of the image detected.

Provided is a hole punching apparatus that is capable of improving the accuracy of stopping at a target reference position. The hole punching apparatus executes a hole-punching process and a braking process, and includes a rotation-detecting unit and a brake-control unit. The hole-punching process punches punch holes by rotating a hole-punching shaft from a reference position. The brake-control unit intermittently turns ON and OFF a short-circuit brake in the braking process. The brake-control unit sets a braking period for turning ON the brake according to the rotation position and rotation speed of the hole-punching shaft that is measured based on the rotation-position signal so that the braking period tends to become longer as the rotation position becomes closer to the reference position, and tends to become longer as the rotation speed becomes faster.

A punching apparatus, including: a punching portion configured to punch a sheet; and a chad box configured to store a chad of a sheet punched by the punching portion, wherein the chad box includes: a first inner wall portion formed of an insulator; and a second inner wall portion formed of a conductor and arranged above the first inner wall portion.

A printing system is disclosed. The printing system includes a printing unit, a sheet processing unit, and a control unit. The sheet processing unit performs a designated sheet process for the printed sheet using a die that is manually selected by a user and attached to the sheet processing unit. When the die for performing the designated sheet process is not attached to the sheet processing unit, it is determined, before the printing unit starts printing the image on a first sheet on which the printing unit prints the image firstly among sheets on which the designated sheet process is to be performed, not to perform the designated sheet process for the sheets on which the designated sheet process is to be performed. The printing unit starts printing the image on the sheets on which the designated sheet process is to be performed after the determination.

A second sheet discharge portion is provided above a first sheet discharge portion in an image forming apparatus. First and second sheet processing units process a sheet discharged from the first sheet discharge portion, and the second sheet processing unit is provided between the first sheet discharge portion and the first sheet processing unit. A first support portion is provided on the first sheet processing unit. A second support portion is disposed upstream of the first support portion in a sheet discharge direction of the second sheet discharge portion and on or above the second sheet processing unit and supports the sheet discharged from the second sheet discharge portion in collaboration with the first support portion.

An MFP receives print data from an information processing apparatus, such as a mobile terminal or a PC. It is determined whether a predetermined character code is included as content in the received print data. A setting is changed so that the post-processing is performed in a position based on a right end of a printed matter in accordance with the determination before the printed matter is output.