An image forming system includes a punch unit, provided in a post-processing apparatus, which includes a punch member that performs punching processing of forming a punch hole in a sheet conveyed along a conveyance path from an image forming apparatus while the punch member rotates, and a detection unit configured to detect a surface property of the sheet conveyed along a conveyance path from the image forming apparatus toward the punch unit. A control unit controls conveyance of the sheet such that the sheet is conveyed to the punch unit at a conveyance speed corresponding to the detected surface property, and controls rotation of the punch member such that the punch member performs the punching processing on the sheet conveyed from the image forming apparatus while the punch member rotates at a rotation speed corresponding to the conveyance speed.

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 sheet processing apparatus includes a conveyance unit configured to convey a sheet in a sheet conveyance direction, a punching unit configured to punch a hole to the sheet being conveyed by the conveyance unit, a moving unit configured to move the punching unit in an intersecting direction intersecting the sheet conveyance direction, a detection unit arranged upstream of the punching unit in the sheet conveyance direction and configured to change an output value based on a position of an edge portion, in the intersecting direction, of the sheet being conveyed, a cleaning portion configured to clean the detection unit, and an interlocking portion configured to move the cleaning portion so as to clean the detection unit by interlocking with a movement of the punching unit in the intersecting direction.

A processing apparatus processing on a sheet includes a punch unit configured to punch a sheet at a punching position while rotating, a first motor configured to drive the punch unit, a first rotary member disposed upstream of the punch unit in a conveyance direction of the sheet and configured to convey the sheet, a second motor configured to drive the first rotary member, a control unit configured to control driving of the first motor and the second motor, and a first detection unit configured to detect a surface speed of the first rotary member. The control unit is configured to adjust a rotation speed of the second motor so that a surface speed of the first rotary member obtained based on a detection result of the first detection unit substantially matches a tangential component of a rotation speed of the punch unit at the punching position.

A processing apparatus processing on a sheet includes a punch unit configured to punch a sheet at a punching position while rotating, a first motor configured to drive the punch unit, a first rotary member disposed upstream of the punch unit in a conveyance direction of the sheet and configured to convey the sheet, a second motor configured to drive the first rotary member, a control unit configured to control driving of the first motor and the second motor, and a first detection unit configured to detect a surface speed of the first rotary member. The control unit is configured to adjust a rotation speed of the second motor so that a surface speed of the first rotary member obtained based on a detection result of the first detection unit substantially matches a tangential component of a rotation speed of the punch unit at the punching position.

An image forming apparatus includes a processing tray, a post-processing controller, and a detection sensor. The processing tray is configured to support a sheet or a sheet bundle on which a post-processing is to be executed. The post-processing controller is configured to execute the post-processing on the sheet positioned on the processing tray. The detection sensor is configured to detect an object in a predetermined detection range including a space above the processing tray. The post-processing controller stops execution of the post-processing when the detection sensor detects the object at a determination timing other than a timing at which passage of the sheet or the sheet bundle through the detection range is estimated.

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 sheet processing apparatus includes a puncher, a first sensor positioned upstream of the puncher in the conveyance direction, a second sensor positioned upstream of the first detection position in the conveyance direction, a drive source configured to drive the puncher, a controller configured to control the drive source. The controller executes a control mode including a first process of controlling a rotation speed of the puncher on a basis of a detection result of the second sensor and a second process of controlling the rotation speed of the puncher on a basis of a detection result of the first sensor. In the control mode, the controller does not stop rotation of the puncher in a period between the punching process on the preceding sheet and a punching process on the succeeding sheet.

An image forming apparatus includes a processing tray, a post-processing controller, and a detection sensor. The processing tray is configured to support a sheet or a sheet bundle on which a post-processing is to be executed. The post-processing controller is configured to execute the post-processing on the sheet positioned on the processing tray. The detection sensor is configured to detect an object in a predetermined detection range including a space above the processing tray. The post-processing controller stops execution of the post-processing when the detection sensor detects the object at a determination timing other than a timing at which passage of the sheet or the sheet bundle through the detection range is estimated.

An image forming apparatus includes a processing tray, a post-processing controller, and a detection sensor. The processing tray is configured to support a sheet or a sheet bundle on which a post-processing is to be executed. The post-processing controller is configured to execute the post-processing on the sheet positioned on the processing tray. The detection sensor is configured to detect an object in a predetermined detection range including a space above the processing tray. The post-processing controller stops execution of the post-processing when the detection sensor detects the object at a determination timing other than a timing at which passage of the sheet or the sheet bundle through the detection range is estimated.