In accordance with an embodiment, a post-processing apparatus comprises a memory that stores a threshold value and a first accumulated data of a physical quantity of one of a motor or a driven member driven by the motor; and a controller that acquires a predetermined data associated with a physical quantity of one of the driving motor or the driven member driven by the motor, acquires a second accumulated data by adding the predetermined data to the first accumulated data read from the memory, compares the second accumulated data with the threshold value, and transmits a request for increasing a discharge interval of the sheet if the second accumulated data is greater than the threshold value.

In accordance with an embodiment, a sheet processing apparatus, containing a controller that acquires a predetermined data associated with a physical quantity of one of a driving motor or a driven member driven by the motor based on a predetermined signal, compare the predetermined data with a threshold value, and determine whether to transmit a request for increasing a discharge interval of a sheet based on the comparative result.

A sheet feed conveyance device includes a warning section, a pickup roller that feeds a sheet, a separation section, a speed sensor that detects a conveyance speed of the sheet, and a controller. The separation section includes a feed roller that feeds downstream the sheet fed by the pickup roller and a retard roller that returns a sheet involved in multiple sheet feeding toward the pickup roller. The controller recognizes the conveyance speed based on output of the speed sensor, integrate conveyance speeds detected in a measurement time period from rotation start of the pickup roller to elapse of a specific time period, and determines necessity for maintenance of the pickup roller according to a measurement distance as a result of integration.

In accordance with an embodiment, a post-processing apparatus comprises a memory that stores a threshold value and a first accumulated data of a physical quantity of one of a motor or a driven member driven by the motor; and a controller that acquires a predetermined data associated with a physical quantity of one of the driving motor or the driven member driven by the motor, acquires a second accumulated data by adding the predetermined data to the first accumulated data read from the memory, compares the second accumulated data with the threshold value, and transmits a request for increasing a discharge interval of the sheet if the second accumulated data is greater than the threshold value.

In accordance with an embodiment, a sheet processing apparatus, containing a controller that acquires a predetermined data associated with a physical quantity of one of a driving motor or a driven member driven by the motor based on a predetermined signal, compare the predetermined data with a threshold value, and determine whether to transmit a request for increasing a discharge interval of a sheet based on the comparative result.

In accordance with an embodiment, a post-processing apparatus comprises a memory that stores a threshold value and a first accumulated data of a physical quantity of one of a motor or a driven member driven by the motor; and a controller that acquires a predetermined data associated with a physical quantity of one of the driving motor or the driven member driven by the motor, acquires a second accumulated data by adding the predetermined data to the first accumulated data read from the memory, compares the second accumulated data with the threshold value, and transmits a request for increasing a discharge interval of the sheet if the second accumulated data is greater than the threshold value.

A sheet feeding apparatus includes a sheet conveying unit configured to convey a sheet along a conveyance path, a detecting unit configured to detect the sheet passing along the conveyance path, a control unit configured to determine an amount of delay of a sheet conveyed along the conveyance path based on the detection and determine information to be output based on the amount of the delay, and an output unit configured to output the information.

A sheet feeding apparatus includes a sheet conveying unit configured to convey a sheet along a conveyance path, a detecting unit configured to detect the sheet passing along the conveyance path, a control unit configured to determine an amount of delay of a sheet conveyed along the conveyance path based on the detection and determine information to be output based on the amount of the delay, and an output unit configured to output the information.

An image forming apparatus including an image forming unit, a conveyance roller, a registration roller disposed on a conveyance path extending from the conveyance roller to the image forming unit, the registration roller being configured to perform skew correction for a sheet by contacting a leading end of the sheet in a conveyance direction while rotation of the registration roller is being stopped, and rotating after a lapse of a particular period of time since the rotation of the registration roller has been stopped, a driving source configured to supply a driving force to the conveyance roller and the registration roller, and a controller configured to determine the particular period of time based on a cumulative number of sheets conveyed by the conveyance roller.