Patent GB-190823672-A (GB)
Title: Improvements in and relating to Two-needle Blind-stitch Sewing Machines.
Inventor: ARBETTER WOLF
Filed: 1908-11-05
Granted: 1909-02-18
Abstract: 23,672. Arbetter, W. Nov. 5. Blind-stitching machines; lock-stitch hook sewing- machines ; overedge-stitching machines ; multipleneedle machines; feed.-A blind-stitch sewing- macbine specially designed for use in " padding " work, in which one or more layers of cloth are united upon a base layer, employs two oppositelyreciprocating needles forming two rows of blindstitches, which are connected to form a seam, preferably by an under-thread from complemental stitch-forming mechanism such as a rotary hook rotating above the presser-foot in a plane transverse and oblique to the work-support. The usual four-motion feed is employed, the dog being shaped to co-operate with two needles, the feedshaft making two revolutions to each revolution of the driving-shaft. The machine may also be used for felling, in which case the stitches formed by one needle enter the upper fabric, while the stitches formed by the other needle enter the main fabric close to the edge of the upper fabric, and the under-thread, as before, holds together the two rows of stitches. If it is desirable that the stitches entering the upper fabric should not penetrate the lower, the one needle must be adjusted to move at a greater distance above the work-support. Worle-supports. - A vertically movable worksupport is mounted in the bed-plate, and is held yieldingly against the presser-foot. The independent bender mechanism for projecting the materials into the needle-paths consists of a bender-bar 7, Fig. 4, provided with two adjustably-mounted benders 8, 9 to co-operate with the two needles. The bender mechanism rises at each stitch, being driven from the feed-shaft, each bender making an idle movement in turn. Needle-driving.-The two needles 13, 16, which are preferably curved and eye-pointed, are mounted on two concentric rock-shafts 11, 14, one surrounding the other and being carried by a projection 10 of the overhanging arm. The shafts 11, 14 carry pinions 17, 18 each geared through half its circumference and lying in parallel planes. The pinions gears with racks 21, 22 carried on the forked arms of a rack-bar 19 which slides in guides 20 in the arm.. The racked fork also presents smooth surfaces to co-operate with the smooth surfaces of the pinions 17, 18, and is provided with a set-screw 23 for taking up wear. The rack-bar 19 is reciprocated by a cam 24 mounted on the end of the main shaft 25, the reciprocation of the rack-bar causing the needles to oscillate in opposite directions. The cam 24 is shaped to secure a dwell of the needles when both are out of the work, white the feed is taking place. Governing needle-thread.-Two independentlyoperating take-ups 28, 29 are provided, and to secure that the oscillation shall be the same in both cases but opposite in phase, they are actuated by studs entering opposite sides of a cam-groove 34, the one take-up 28 being mounted on a shaft 31 and provided with a stud-carrying rocker-arm 32, the other, 29, being fast on a sleeve journaled on the shaft 31 and also provided with a stud-carrying rocker-arm. The threads are supplied from spools 39, 40, and each thread passes through a suitable tension 41, 42 and a suitable pull-off 43, 44.