Material web fixing device as part of a filter bag manufacturing installation

A material web fixing device as part of a filter bag manufacturing installation, comprising

• a material web transport device for the transport of at least two material webs to be fixed, by means of a fixing seam, at a distance from one another along a transport direction,
• a plurality of sewing units with in each case one sewing needle and a looper acting as stitch forming tools between which the material webs can be passed through in the transport direction, the stitch forming tools interacting with a thread to produce the fixing seam,
• an excess thread production unit to lengthen a thread path between the material webs,
• the excess thread production unit being arranged in the thread run between the material webs during operation,
• the excess thread production unit having in each case an oblique surface running at an angle to the transport direction, the oblique surface being arranged between the material webs during operation in such a way that it is passed over by the thread during seam formation due to the transport via the material web transport device,
• with each sewing unit being associated to a respective one of the oblique surfaces.