Sheet conveyance device

A sheet conveyance device comprising:na first conveyance unit which includes a first holder that holds a leading edge of a sheet with respect to a conveyance direction, and conveys the sheet held by said first holder;a second conveyance unit which includes a second holder that holds a leading edge of the sheet with respect to a conveyance direction, and conveys the sheet held by said second holder;a third conveyance unit which is supported to be swingable between a reception position at which said third conveyance unit receives the sheet from said first conveyance unit, and a transfer position at which said third conveyance unit transfers the sheet to said second conveyance unit, said third conveyance unit including a third holder that holds a trailing edge of the sheet with respect to the conveyance direction while the sheet is being conveyed by said first conveyance unit, and said third conveyance unit configured to receive by said third holder the trailing edge of the sheet conveyed by said first conveyance unit, to rotate in a first direction directed from the reception position to the transfer position, to transfer the received trailing edge of the sheet to said second holder of said second conveyance unit by a gripping change, and to rotate in a second direction opposite to the first direction;an independent driving unit which independently drives said first conveyance unit;a device driving unit which drives an entire device including said second conveyance unit and said third conveyance unit; anda control unit which controls said independent driving unit to adjust a speed at which said first conveyance unit conveys the sheet, based on a dimension of the sheet in a conveyance direction.