Belt conveying device and rewinding machine

The utility model provides a belt conveying device and a rewinding machine. The belt conveying device comprises a first belt wheel set and a second belt wheel set. The belt conveying device further comprises a first belt keeping mechanism and a linear moving mechanism. The first belt wheel set, the second belt wheel set and the first belt maintaining mechanism are sequentially arranged along a belt conveying route. The first belt retaining mechanism and the second belt wheel set are both arranged on the linear moving mechanism. The linear moving mechanism can move between a first position and a second position in the first direction. Before and after the linear moving mechanism moves, the distance from the second belt wheel set to the first belt wheel set and/or the distance from the second belt wheel set to the first belt wheel set are/is not changed. The rewinding machine comprises the belt conveying device. The utility model can ensure the consistent tensioning degree before and after the adhesive tape is