GB360213A - Zigzag-stitch sewing machines - Google Patents

Abstract

360,213. Sewing-machines. SINGER MANUFACTURING CO., Elizabeth, New Jersey, U.S.A. Nov. 24, 1930, No. 35286. Convention date, Jan. 10. [Class 112.] Needles, vibrating laterally.-Improved mechanism for vibrating the needle laterally and for maintaining loop-seizing relationship between the needle and loop-taker comprises a pitman having a strap completely embracing an eccentric which vibrates the needle-bar frame and loop-taker. The main shaft 6 having the usual crank disc 7 and link 8 for reciprocating the needle bar 9, is journalled in the arm 4. The bar 9 reciprocates in a frame 11 pivoted at its upper end at 12. The frame 11 is pivoted to a link 14 by a stud 13. The other end of the link is connected by a bolt 15 to an arm 16 of a two-armed pitman 16, 17. The pitman has a split hub 18 embracing the operating eccentric 19 extending laterally from a frame 20 pivotally supported on a screw-bolt 21 or a disc 22 secured to the shaft 25. This shaft carries a worm wheel 26 driven by a worm gear 27 on the main shaft 6. In order to adjust the eccentric 19 with respect to the shaft 25, and so change the effective endwise movement of the pitman, a rod 28 is threaded into the bore of the shaft 25 and is screwed up by the nut. 29. The tapered end 30 of the rod engages the round end of the screw 31 and moves the spring plunger 32, to move the eccentric. The arm 17 of the pitman is connected by a pin 35 to an arm 36 of the rocking lever 36, 37 pivoted at 40. The other arm 37 has a threaded aperture receiving the ball-headed screw 41 universally jointed to the arm 45 of a second rocking lever 45, 46. The ball slot 44 is slightly elongated and provided with a clamping screw 47 for varying slightly the throw of the arm 45 with that of the arm 37. The arm 46 is connected by a flat spring 46 to the reciprocating bar 50 journalled in the work supporting arm 2 and having a reduced end 51 secured by a pin 52 to the apertured loop-taker bracket 53. The bracket 53 has fins 54 engaging fixed shoulder 55 to prevent rotary movement. The loop-taker 57 is carried on the vertical shaft 56 and is of the rotary hook type. The loop-taker is situated to one side of the needle path enabling the work supporting arm to be terminated abruptly adjacent the needle path as is desirable for certain kinds of work. The shaft 56 carries a bevel gear 61 meshing with a gear 62 of twice the size of the gear 61, on the actuating shaft 64. The shaft 64 carries a pulley 65 driven from the main shaft 6. The bracket 53 carries a fork 68 straddling a groove 69 provided between the gear 62 and collar 70 so that the gear is constrained to move laterally with the loop-taker, while rotating with the shaft 64.