Einrichtung an einer Zweinadelnaehmaschine zum Einruecken und Ausruecken der Nadelstangen

摘要

922,243. Sewing-machines. MECCHI S.p.A. May 3, 1960 [Jan. 25, 1959], No. 15487/60. Class 112. A sewing-machine has means for engaging and driving the needle bars which may selectively release one bar, stopping means being provided to engage the said one bar and hold it in a predetermined raised position. The two needle bars 1, 11 are each of semicircular cross-section and are reciprocable within the sleeves 2, 3 rigidly mounted on a support 4. The needle bars are each provided (see Fig. 4) with grooves 16, 161, 17, 171 leading to transverse bearing surfaces 14, 141, 15, 151 respectively. A control rod 6 disposed parallel to the needle bars is slidable in the lower sleeves 8, 9 and an upper sleeve 7 mounted on the housing 4. The control rod is reciprocated by a connecting member 5 secured to the lower end of the rod and driven from the main shaft of the sewing-machine. The driving connection between the rod 6 and each of the needle bars is provided by the engagement (see Figs. 7 and 10) of a driving member 12, mounted on the bar with the transverse surface 14 and/or 141 on the appropriate needle bar, the member 12 having a protrusion which may engage either or both of the bars according to the angular position at which the rod 6 is set. A stopping member 13 splined to the rod 6 is disposed between sleeves 8, 9 and has protruding tips 36, 361 one of which, according to the angular position of the rod, will engage the surface 15 in whichever needle bar is disengaged by the driving member 12 so as to hold that bar in a raised position. The rod is selectively rotatable by a handle 31 (see Fig. 1) connected to a quadrant engaging a toothed sector 7 (see Fig. 7) splined on to the rod 6. A stop 32 limits the angular movement of the rod. A resilient member 28, disposed between the handle 31 and the sector, permits the handle 31 to be moved when the bearing surfaces 14, 15 are not aligned with the driving and stop members. Disengagement or engagement of the appropriate bar is then achieved when the needle bar is next in a position to bring the appropriate surface into alignment with the corresponding member. The handle 31 is provided with a centring spring 40. The housing 4 is pivoted at 10 so that the work may be fed by movement of the needles, sufficient clearance being allowed between the teeth on the quadrant and on the sector 7 to permit oscillation of the housing. The needle bars may have cross sections other than those mentioned, and may slide inside independent sleeves.