GB304679A - Improvements in sewing machines - Google Patents

Abstract

304,679. Roseman, L. Jan. 24, 1928, [Convention date]. Feeding long lengths of fabric; eyeletted tape attaching machines.-A sewing-machine for attaching tapes with metallic fasteners has positioning means synchronised with the feed to engage the fasteners while the needle enters just in front of and just behind each fastener, to prevent the needle catching thereon owing to uneven feeding at high speed. In the example illustrated, a machine has a needle bar 12 carrying two needles 12<1>, 12<11> which vibrate laterally to assist the feed dog 15. The tape 18 is passed over a roller 39, between feed-rollers 36, 45, Fig. 3, and over the work support to the feed dog 15 where it and the fabric 19 are clamped down by the presser foot 13. The needle bar is reciprocated in the usual way by a main shaft 14. This shaft drives a vertical shaft 24 through gearing 25, 26, Fig. 1, which in turn drives a shaft 33 through gears 30, 31, 35 to drive the feed rollers 36, 45. These rollers can be separated against a spring 48 to insert the tape by a lever 49 and cams 51. Fig. 3. To ensure even feeding of the tape, a bar 54 having a fastenerengaging end 55, Fig. 1, is reciprocated synchronously with the feed by a lever 56 pivoted at 58 and rocked by the roller 59 and eccentric 60 on the shaft 29. The shaft 29 is driven by gears 31, 30 from the shaft 24. For ensuring that the fasteners do not accidentally occupy a position below the needle owing to uneven feed at high speed, a positioning device carried by the pivoted frame 63 is provided just in front of the sewing point. This device comprises two bars 68, 78, Fig. 5, the bar 68 of which engages the fastener 20 to prevent its forward movement while the needle enters in front of the fastener at a. When the needle is withdrawn, the bar 68 is also withdrawn by a lever 73, Fig. 1, operated by the face 91 of the cam 90 driven by the shaft 29. The tape 18 is then fed forward till the fastener 20 is stopped by engaging the bar 78. The needle then enters just behind the fastener. When the needle is withdrawn, the face 92 of the cam 90 imparts a further retrograde movement to the bar 68 which moves back the bar 78 by the engagement of the pin 86 with the shoulder 85. To permit the device to be set for fasteners of differing width, a nose 87<1> in the boss 87 can be caused to engage a cam surface on a disc on the shaft 29, which is normally out of action. This causes the casing 63 to swing about its pivot to allow for narrow or wide fasteners. By employing a double faced cam to co-operate with the nose 87', one bar only can be used to engage the fastener in both its positions relative to the needle.