Sewing machine attachments

Claim 1

IN A FOLDER FOR THE FORMATION OF WELTING OR THE LIKE, A BASE, A PAIR OF SPACED MEANS FOR GUIDING A PAIR OF SPACED CORDS, A WALL STRUCTURE OPERATIVELY CONNECTED TO EACH OF SAID GUIDING MEANS, SAID BASE AND WALL STRUCTURES TOGETHER FORMING A CASING-LIKE STRUCTURE DEFINING A GRADED PASSAGE WHEREIN THE BORDERS OF A FABRIC WEB BEING PASSED THERETHROUGH ARE FOLDED AROUND A PAIR OF CORDS PASSED THROUGH SAID GUIDING MEANS AND ADAPTED TO BE DELIVERED TO DOUBLE STITCHING MEANS WHICH SIMULTANEOUSLY FORMS A ROW OF STITCHES IN EACH OF SAID BORDERS OF SAID WEB ADJACENT TO EACH OF SAID CORDS, SAID FOLDER INCLUDING MEANS CONNECTING AT LEAST ONE OF SAID GUIDING MEANS AND ITS WALL STRUCTURE TO SAID BASE IN A MANNER PERMITTING DISPLACEMENT RELATIVE TO THE OTHER OF SAID GUIDING MEANS AND ITS WALL STRUCTURE, WHEREBY SAID FOLDER CAN BE ADJUSTED TO VARY THE SPACING BETWEEN SAID CORDS, A PIN ON EACH OF SAID WALL STRUCTURES, A TONGUE PIVOTALLY SUPPORTED ON SAID PINS BETWEEN SAID WALL STRUCTURES, MEANS PROJECTING FROM AT LEAST ONE OF SAID WALL STRUCTURES, AND SPRING MEANS EXTENDING BETWEEN SAID TONGUE AND SAID PROJECTING MEANS AND RESILIENTLY URGING SAID TONGUE AGAINST A FABRIC WEB PASSED THEREBELOW.