| 摘要 |
PROBLEM TO BE SOLVED: To provide a sheet stacking apparatus capable of eliminating a useless space by making a mechanism compact in size to move a tray and capable of stacking a large amount of sheets, a post-processing apparatus, and an image forming apparatus.SOLUTION: In an in-body paper ejection type image forming apparatus 10, an external tray 52 is supported by a sidewall 26 of a post-processing part 30 so as to move vertically. A spacer 54 is supported by the upper surface 24 of an image forming part 14 so as to move horizontally. When the spacer moves horizontally, the external tray 52 moves vertically following the movement. |
