GB992456A - Improvements in or relating to attachment means for sewing machines - Google Patents

Abstract

992,456. Sewing machines. KAYSER BONDOR Ltd. Jan 8, 1964 [Jan. 12, 1963], No. 1481/63. Heading D1G. A machine for sewing on patches comprises means for feeding a predetermined length of tape, means for severing said length from the remainder, and means for delivering said length in a folded condition to a work-holding clamp adjacent the needle. A sewing machine 1 is provided with a clamp feed having a lower jaw 3 and an upper jaw 6 adapted to form a U-shaped line 55 of stitching to secure a folded patch 54, cut from a tape 9, over the rolled end of a pair of members 52 for covering thereat the protuberant seam 53 interconnecting the latter. Tape 9 is fed by means mounted on a plate 14 slidable transversely in guides 15. The tape first passes through a guide 37, then between serrated wheels 38 and the serrated end of a shaft 29, and finally beneath an upwardly spring-biased blade 36. The wheels 38 are carried by a shaft 40 journalled in arms 39 which are pivoted to plate 14. The distance between wheels 38 and shaft 29 is adjustable by means of screws 41 extending through arms 39 and engaging plate 14. Shaft 29 is driven intermittently via a uni-directional clutch 30 by a gear pinion meshing with a gear sector 26 oscillated by a link 27. A lever 20, pivoted at 21, is coupled at one end to plate 14 and at the other end to a pair of opposed solenoids 22, energization of one or the other of which thereby serves to shift plate 14 to one side or the other. A pair of pivoted arms 34 carry between their free ends a heated wire 25. One arm 34 is engaged between collars on a shaft 33 which is slidable in plate 14 and is coupled to one end of a linkage 13, the other end of which co-operates with a cam 12 on a shaft 10. A pair of arms 8, rigid with shaft 10, carry at their free ends a bar 79. A sprocket wheel 11 or shaft 10 is connected by a chain 51 to the piston of a pneumatic jack which is normally positioned to maintain wire 25 above plate 14 and bar 79 rearwardly of the jaws 3, 6. After a length of tape has been fed beneath the blade 36, and the jaws 3, 6 being open, a pedal is depressed to effect movement of the jack piston to its other end position and also energization of a solenoid controlling an arm 35. The latter thus engages blade 36 to clamp the tape against plate 14, and wire 25 engages the tape at a position 43 to sever a patch length 54 therefrom. Bar 79, which is rendered adhesive, then engages patch length 54 at a position 44. During the return stroke of the jack piston, bar 79 carries patch length 54 within the jaws 3, 6 in folded U-shape formation. The seam 53 at the rolled end of members 52 is inserted into the folded patch 54 and stitching is commenced. Plate 14 is shifted in accordance with the line of stitching by actuation of a microswitch effected by movement of the work-feed clamp.