GB279100A - Improvements in or relating to sewing machines - Google Patents

Abstract

279,100. Union Special-Maschinenfabrik Ges. Oct. 14, 1926, [Convention date]. Machines with work benders.-In a blind-stitch machine in which the fabric is fed along a fixed ridge, the eccentric driving the curved needle and the three eccentrics controlling the movement of the thread-carrying looper are mounted on one auxiliary shaft. The curved needle 19 is carried by a bar 17 having bearing eyes 15, 16 supported at opposite ends of a main pivot pin 13, and the eye has an arm having a ball-joint connection 12 with the needle-driving eccentric. The looper 42 is fixed upon a spindle 44, which is rotated and moved axially in a sleeve 48 pivotally mounted by means of an eye 49 on the pivot pin 13. The whole is oscillated about the pin 13 by an eccentric having a ball-joint connection 51 with the sleeve 48. The looper spindle is oscillated about its own axis by an eccentric having a ball-joint connection 47 with the spindle. The looper is raised and lowered to clear the work-supporting ridge 43 by means of a third eccentric balljointed to an arm 57 mounted on the pivot-pin 13. The arm 57 is linked by a member 60 to a lever 63 pivoted at 61 to the machine frame and connected by a link 65 to a sleeve 67 confined between two collars 68, 69. fixed on the looper spindle. In order to permit adjustment of the height of the needle and looper in relation to the work-supporting ridge, the pivot pin comprises a round bearing part 13 and two supporting pieces 121, 122, which have flat-sided wedge-shaped extensions 21, 22 entering corresponding slots in the ends of the part 13. The inclined surfaces 78 are held in contact by springs 24 and the pieces 121, 122 may be moved towards or away from one another to vary the height of the axis of the pivot by means of nuts 76. The nuts are prevented from axial movement by grub screws 79, which enter annular grooves in a circular part 77 of the machine frame and serve also to lock the nuts from rotation. The Specification as open to inspection under Sect. 91 (3) (a) comprises also the following subject-matter, which does not appear in the Specification as accepted. Trimming or cutting.-The bar 31 carrying a movable cutter comprising two blades 25 is slidingly mounted within the presser-bar and is furnished with a pair of slide blocks 30. Arcuate bars 29 carried by the oscillating needle-bar 17 engage the blocks and being positioned eccentrically to the pivot pin 13 cause an axial movement of the cutter-bar. Stitched seams.-The machine is adapted to sew the known seam shown in Fig. 11 (Cancelled). and also the butt seam shown in Fig. 15 (Cancelled). In the latter the upper edge of the seam is open during the formation of each stitch, but is closed by the tightening of the stitches and a flat seam is produced.