Discharge sheet stacking apparatus and image forming apparatus provided with the same

An image forming apparatus comprising:

• an image forming apparatus main body having an openable and closable portion that is openable and closable;
• an image forming portion provided in said image forming apparatus main body and which forms images on sheets;
• and
• a discharged sheet stacking apparatus, said discharged sheet stacking apparatus comprising:
• a sheet treating portion which effects treatment on the sheets on which images have been formed by said image forming portion;
• a discharged sheet stacking tray provided in the lower portion of said sheet treating portion and on which the sheets discharged from said sheet treating portion are stacked, a position of said discharged sheet stacking tray being variable;
• and
• a holding portion which holds said discharged sheet stacking tray at a first position or a second position above the first position,
• wherein said discharged sheet stacking tray is located above the openable and closable portion.

An image forming apparatus comprising:

• an image forming apparatus main body having an openable and closable portion which is openable and closable;
• an image forming portion provided in said image forming apparatus main body and which forms images on sheets;
• and
• a discharged sheet stacking apparatus,
• wherein said discharged sheet stacking apparatus includes:
• a sheet treating portion which effects treatment on the sheets on which images have been formed by said image forming portion;
• a discharged sheet stacking tray provided in the lower portion of said sheet treating portion and which stacks the sheets discharged from said sheet treating portion, a position of said discharged sheet stacking tray being variable;
• a holding portion which holds said discharged sheet stacking tray at a first position or a second position above the first position;
• and
• a contact preventing portion disposed at a location where said discharged sheet stacking tray abuts on said openable and closable portion in a state in which said openable and closable portion is opened, and wherein said contact preventing portion prevents said discharged sheet stacking tray from contacting with an operating portion provided on said openable and closable portion.

An image forming apparatus main body which forms images on sheets and to which a discharged sheet stacking apparatus is detachably connected, comprising an openable and closable portion,

• said discharged sheet stacking apparatus including:
• a sheet treating portion which effects treatment on the sheets on which images have been formed by an image forming portion;
• a discharged sheet stacking tray provided in the lower portion of said sheet treating portion and on which the sheets discharged from said sheet treating portion are stacked, a position of said discharged sheet stacking tray being variable;
• and
• a holding portion which holds said discharged sheet stacking tray at a first position or a second position that is above the first position,
• wherein said openable and closable portion is provided at a location where said discharged sheet stacking tray abuts on said openable and closable portion in a state in which said openable and closable portion is opened, and has a contact preventing portion which prevents the contact of said discharged sheet stacking tray with an operating portion provided on said openable and closable portion, and said contact preventing portion is a convex portion of a predetermined height detachably provided on said openable and closable portion, and is disposed at a location without contacting said operating portion.

A discharged sheet stacking apparatus comprising:

• a sheet treating portion which effects treatment on conveyed sheets;
• a discharged sheet stacking tray provided in the lower portion of said sheet treating portion on which the sheets discharged from said sheet treating portion are stacked, a position of said discharged sheet stacking tray being variable;
• a holding portion which holds said discharged sheet stacking tray in a first position or a second position above the first position;
• and
• a position detecting portion which detects that said discharged sheet stacking tray is at the second position;
• wherein the sheets are discharged from said sheet treating portion to said discharged sheet stacking tray at the first position, and
• wherein said position detecting portion also detects that said discharged sheet stacking tray is fully loaded with said sheets.