Booklet-loading device, post-treatment device and image-forming system

A booklet-loading device comprising:

• a carry-out unit that conveys a plurality of booklets sequentially;
• a transfer unit that transfers the plurality of booklets sequentially conveyed from the carry-out unit, and arranges the plurality of booklets in a partly overlapped state;
• a loaded unit that is loaded with the booklets transferred by the transfer unit;
• and
• a transfer control unit that controls a transfer amount per booklet in the transfer unit to a transfer amount depending on a quantity of booklets loaded on the loaded unit,
• wherein the transfer unit performs intermittent transfer of the booklets in which movement of the booklets for set time and stop of the booklets are repeated in synchronism with the conveyance of the booklet from the carry-out unit to the transfer unit, the set time being represented by the transfer amount controlled by the transfer control unit,
• wherein the booklet-loading device is connected to a bookbinding device that binds booklets according to specified bookbinding conditions showing at least one of thickness, number, size of paper composing the booklets, and presence or absence of square folding process to form the booklets in a flat back, and the booklet-loading device further comprises a sensor which detects arrival of the first booklet of the plurality of booklet near the loaded unit by being transferred by the transfer unit, and
• wherein the transfer control unit determines a reference transfer amount on the basis of the bookbinding conditions specified in the bookbinding device, and controls the transfer amount per booklet in the transfer unit
• (a) to a transfer amount which is larger than the reference transfer amount before the sensor detects the arrival of the first booklet,
• (b) to a transfer amount which is the same as the reference transfer amount after the sensor detects the arrival of the first booklet and before the quantity of booklets loaded on the loaded unit reaches a predetermined high density loading standard,
• (c) to a transfer amount which is smaller than the reference transfer amount after the sensor detects the arrival of the first booklet and after the quantity of booklets loaded on the loaded unit reaches the predetermined high density loading standard.