Feeding device, image forming system, and conveyed medium inspection system

A feeding device to feed a conveyed medium stacked on a stacker and to be conveyed in a conveyance direction away from the feeding device, the feeding device comprising:

• a first suction unit disposed and configured to apply a suction force to attract a leading edge of the conveyed medium from a stacked position of the conveyed medium, the first suction unit including:
• a suction chamber;
• a suction fan disposed downstream in an air flow direction of, and external to, the suction chamber to draw air from the suction chamber;
• and
• a first driver to rotate the suction fan;
• a second suction unit disposed upstream, in the conveyance direction, of the first suction unit and configured to generate a vortex air directed to the conveyed medium, including:
• a rotary fan including
• a board having a planar surface and
• a plurality of walls attached on the planar surface of the board;
• and
• a second driver to rotate the rotary fan;
• a moving device to move the second suction unit in a direction parallel to the conveyance direction of the conveyed medium;
• and
• a controller to control operation of the moving device until the second suction unit takes a predetermined position within a range where a suction force is exerted on an upstream end, in the conveyance direction, of the conveyed medium,
• wherein the first suction unit and the second suction unit are different types of suction devices and are disposed above the conveyed medium stacked on the stacker to attract the conveyed medium,
• operation of the suction fan, which is downstream in the air flow direction of, and external to, the suction chamber, causing a negative pressure to be generated in the suction chamber and thereby drawing air flow to apply the suction force attracting the leading edge of the conveyed medium from the stacked position of the conveyed medium, and
• the second suction unit generating a suction force that is stronger than that generated by the first suction unit, and
• wherein the second driver of the second suction unit is attached to a surface of the moving device which opposes at least a portion of the conveyed medium stacked on the stacker.

A feeding device to feed a conveyed medium stacked on a stacker and to be conveyed in a conveyance direction away from the feeding device, the feeding device comprising:

• a first suction unit disposed and configured to apply a suction force to attract a leading edge of the conveyed medium from a stacked position of the conveyed medium, the first suction unit including:
• a suction chamber;
• a suction fan disposed downstream in an air flow direction of, and external to, the suction chamber to draw air from the suction chamber;
• and
• a first driver to rotate the suction fan;
• a second suction unit disposed upstream, in the conveyance direction, of the first suction unit and configured to generate a vortex air directed to the conveyed medium, the second suction unit including:
• a rotary fan including
• a board having a planar surface and
• a plurality of walls attached on the planar surface of the board;
• and
• a second driver to rotate the rotary fan;
• and
• a controller to control operations of the first suction unit and the second suction unit,
• wherein upon receiving a feed start command, the controller activates the first driver to start rotating the suction fan to draw air from the suction chamber and thereby apply the suction force to attract the leading edge of the conveyed medium from the stacked position of the conveyed medium, and then activates the second driver to rotate the rotary fan to generate the vortex air directed to attract a trailing edge of the conveyed medium,
• wherein when the second driver is activated, the second suction unit generates the vortex air directed to attract the trailing edge of the conveyed medium and generates a suction force that is stronger than that generated by the first suction unit.