Equipment for stacking sheets with a stack support, input rollers for feeding entering sheets and transport belts with lower branches arranged above the stack support. A compensation mechanism modifies the height of the stack support, while the transport belts are motorized to drag the entering sheets with the lower branches and deposit the sheets on the stack support or on stacked sheets. An arrest member is provided for the entering sheets, a pressure member for the stack to be stacked and a sensor device for a last sheet of the stack. The arrest member arrests the sheets in stacking while the pressure member is contiguous to the stop member and operates on the last sheet of the stack with a stabilizing function and in which the compensation mechanism is servoized to the sensor, for maintaining constant the height of the last sheet of the stack from a reference plane.

An image forming system includes a conveying member which conveys a sheet along a conveying direction; and a separation device which separates the sheet from the conveying member at a separation position. The separation device includes an air flow generating part and a duct. The air flow generating part generate an air flow. The duct which blows the air flow generated by the air flow generation part, from a position above the sheet to a downstream side in the conveying direction at the separation position.

A feeding device includes: a loading portion that is disposed on a downstream side of a transporting path in a transporting direction and that loads a transporting target, which is transported through the transporting path, on a loading surface inclined with respect to a horizontal direction; and a feeding unit that feeds the transporting target, which is in contact with the loading surface, obliquely upward along the loading surface.