Sheet discharge device, and sheet postprocessing device, image forming apparatus, plus image forming system each including the sheet discharge device

An image forming system comprising:

• an image forming apparatus for forming images on sheets;
• and
• a sheet postprocessing device including:
• a processing part for performing specified postprocessing on sheets;
• and
• a sheet discharge device for discharging the sheets having been subjected to postprocessing by the processing part, the sheet discharge device including:
• a sheet discharge port through which sheets are discharged;
• a discharge member which is placed at the sheet discharge port and which conveys the sheets in a discharge direction;
• a sheet discharge tray which is placed on a downstream side of the sheet discharge port in the discharge direction and on which the sheets discharged from the sheet discharge port are to be stacked;
• a support member movable between a projective position in which the support member is projected from the sheet discharge port to above the sheet discharge tray so as to support an upstream portion of the sheets in the discharge direction and a retractive position in which the support member has retracted from the projective position to an upstream side of the sheet discharge port;
• a drive mechanism for driving the support member;
• and
• a controller for controlling the drive mechanism,
• the controller being enabled to adjust at least one of a projective length of the support member in its projective position and a shift timing from the projective position to the retractive position in response to characteristics of the sheets
• wherein
• the image forming system further includes:
• an input part for entering output information as to characteristics of the sheets and
• a projective length of the support member in the projective position, as well as the shift timing of the support member from the projective position to the retractive position, are arbitrarily adjustable by entry operation to the input part.