A conveyer includes: a supporting member which supports a roll body having a sheet wound therearound; a conveyance roller which conveys the sheet; a guide member; an urging member which urges the guide member; a sensor; and a controller. The controller is configured: to determine a target position of the guide member and a permissible position in accordance with the target position; to control a rotation amount of the supporting member and/or a rotation amount of the conveyance roller; to determine whether or not a position of the guide member exceeds the permissible position; and to perform a notification of a conveying error of the sheet.

A conveyer includes: a supporting member which supports a roll body having a sheet wound therearound; a conveyance roller which conveys the sheet; a guide member; an urging member which urges the guide member; a sensor; and a controller. The controller is configured: to determine a target position of the guide member and a permissible position in accordance with the target position; to control a rotation amount of the supporting member and/or a rotation amount of the conveyance roller; to determine whether or not a position of the guide member exceeds the permissible position; and to perform a notification of a conveying error of the sheet.

Provided is a method for conveying a sheet member while the sheet member is supported by a roller member, the method including: detecting forces applied, by the sheet member supported by the roller member, to regions at both ends in a width direction of the roller member, respectively, as force components in a plurality of mutually different directions; and adjusting the force components in the regions at both ends in the width direction to a specific balance based on the detection results for the plurality of force components.