GB1271319A - Improvements in or relating to sewing machines - Google Patents

Abstract

1,271,319. Blind stitch sewing machine. UNION SPECIAL MACHINE CO. 15 Aug., 1969 [19 Aug., 1968], No. 40809/69. Heading DIG. A blind stitch sewing machine comprises a frame having a base 10, a vertically extending standard 11, a laterally extending arm 12 at the upper end of the standard and a forwardly extending arm 14 adjacent one end of the arm 12, a rockable work support 22 extending laterally from the base to a region beneath the end of the arm 14, a main drive shaft 15 journalled in the laterally extending arm 12, an oscillatable ridge former carrying shaft 24 in the work support, and connections from the drive shaft 15 to the ridge former shaft 24 including a shaft 28 mounted in the frame beneath the drive shaft, a toothed pulley 30 secured to drive shaft 15, a toothed pulley 27 on the shaft 28, a toothed belt 29 connecting the pulleys, an eccentric 27a connected with the pulley 27 and a pitman 26 connecting the eccentric to the shaft 24. The ridge former may be of the dual type, described in Specification 1,019,727, which is rotatable through 180‹ on shaft 24 to select the former portion suitable for hard or for soft finish work. The work support is oscillatable about its pivot 23, to produce skip stitches, by a spring biassed rod 35 movable axially by levers 32, 33 pivoted at 31 and 33a respectively. A disc 33d on lever 33 co-operates, to this end, with an eccentric on a shaft driven from shaft 15 by a belt 20. A knob 34 can vary the position of pivot 33a to vary the position of the work support. An adjustable fork 38b can vary the position of disc 33d to cause the latter to co-operate with a non-eccentric disc on the driven shaft when skip stitches are not required. Looper drive (Fig. 3, not shown). The main shaft 15 carries an eccentric inclined crank (17f) connected to a pivoted arm (18) by a reciprocable and oscillating rod (17c) having a spherical bearing engagement with the pivoted arm (18). The latter is adjustably pivoted on an eccentric portion of a shaft (18) which is supported at either end in arm 14 in a normally fixed, but adjustable, position. The feed bar (41, Fig. 8, not shown) for the feeding foot (41b) is cranked to clear the shaft (18). The machine is connected to a table board (Fig. 9, not shown) by anti vibration devices.