Sheet conveying device and method for adjusting sheet conveying device

A method for adjusting a sheet conveying device that includes a first conveying portion at which a band-like sheet including a first surface and a second surface on an opposite side of the first surface is conveyed with the first surface facing downward, a turn portion that includes a convex surface an axial line of which extends in a width direction of the sheet, is provided at downstream of the first conveying portion in a conveyance direction of the sheet, and turns the sheet along the convex surface with the first surface facing inside, a second conveying portion provided at downstream of the turn portion in the conveyance direction and at which the sheet is conveyed with the second surface facing downward, and an air jet device that includes an air nozzle that is provided at a boundary portion between the first conveying portion and the turn portion and extends in the width direction of the sheet and jets air from the air nozzle,

• the convex surface including
• a small-diameter portion that is opposed to a central portion of the sheet in the width direction, and
• a pair of large-diameter portions that are arranged at both sides of the small-diameter portion in an axial direction, protrude outward from the small-diameter portion in a radial direction, and support both end portions of the sheet in the width direction,
• the air nozzle being configured such that a width thereof in the conveyance direction can be adjusted,
• the method comprising:
• measuring a difference in position in the radial direction between the both end portions of the sheet in the width direction supported by the pair of large-diameter portions and the central portion of the sheet in the width direction;
• and
• adjusting the width of the air nozzle in the conveyance direction such that the measured difference in position in the radial direction is in a preset range.