Guiding device for the formation of a fold along the edge of a fabric

A guiding device for forming a regular fold on a supple piece before a stitching station intended for automatically closing the fold,

• wherein it comprises, placed in the vicinity of the stitching station and upstream thereof in the direction D of displacement of the piece in the course of stitching,
• a. a passive guiding assembly, consisting of two elements, one being placed inside the other during formation of the fold:
• the inner element whose two upper and lower faces are plane and horizontal, the lower face being substantially in the working plane of the stitching station,
• the outer element having the form of a U and enveloping the inner element on one side and the two horizontal faces, these two elements being positioned with respect to each other so that there exists between said elements a U-shaped recess sufficient to allow passage of the supple piece and effecting formation of the fold, upon passage of the piece in the bent part of said recess,
• b. a correction device comprising:
• a device for detecting the presence of the piece placed, beneath the passive guiding assembly, at a distance approximately equal to the width of the desired fold with respect to the bent part of the recess between the two elements of the passive assembly;
• an active guiding assembly consisting of at least one active guide, abutting on the supple piece when it is in contact with one of the faces of the inner element, and ensuring displacement of the piece substantially transversely with respect to the direction D of stitching as a function of the instructions given by the detection device.