Patent GB-190912295-A (GB)
Title: Improvements in and relating to Seams for Sewed Articles, and Machinery for Producing the same.
Inventor: ARBETTER WOLF
IPC: D05B35/02
Filed: 1909-05-25
Granted: 1909-09-16
Abstract: 12,295. Arbetter, W. May 25. Seams.-For attaching the edge of a superimposed layer of fabric to a base layer by blind-stitching, a seam is used in which only a series of parallel stitches extending substantially at right-angles to the edge, and a short distance over the superimposed layer are visible. The seam may be formed by any suitable needle and co-operating mechanism, but is described as being formed by a curved needle co-operating with a rotary hook. In forming the seam the needle 3 first enters the base layer 1 at 4 and emerges at 5, these points lying close up to the edge of the upper layer 2. The hook thread 7 then passes through the loop 6 and the needle retreats and is turned into a diagonal direction to enter the layer 2, from which it emerges at the point 8. The hook thread again passes through the needle-loop 9 and the needle retreats, the tension being so arranged as to draw the thread 7 into the fabric. Upon the completion of its retracting movement, the needle is again swung round to form a loop 10 parallel to the loop 6, and this loop is again entered by the hook thread. The feed takes place after the formation of this loop and the process is repeated. The tension will draw up the loops 6, 10 to practically conceal them under the edge 2, so that only the double strands of hook thread that cross the edge will be visible. Blind-stitch sewing-machines; needles, vibrating.-The machine for making the seam shown in Fig. 1 is of the type described in Specification 19,080/06, and employs a curved needle 3 carried on an arm 12 of a rock-shaft 13, the bearing of which is connected to a shaft 16 through a block 15. The shaft 13 is rocked to reciprocate the needle by connection to a rod 17 eccentrically connected to a disk 18 on the driving-shaft, and the needle so vibrated by oscillating the shaft 16, an arm 23 of which carries an adjustable roll 24 which is held by the spring 25 in contact with a face-cam, which is driven by a pinion at one-third the speed of the main shaft. The cam thus makes one revolution for three needle reciprocations, and it is raised for one-third of its surface and so adjusted that reciprocation of the needle occurs while the roll 24 is in contact with this raised part, so that two of the needle reciprocations will take place in the line of feed and the third in a line diagonal thereto. The rotary hook 29 is driven from the inclined shaft 30 by bevelgearing 31 meshing with a bevel on the main shaft and is preferably arranged to make two rotations to each needle reciprocation. Feed by dog; work supports.-The bender 41 is actuated from a cam 44, Fig. 6, which is driven at one-third of the rate of the driving- shaft, through a pivoted lever 43 which carries a roller 45 engaging the cam. The cam is shaped to depress the bender twice during a revolution, once during the feed and once while the needle is making its diagonal stitch. The work support 33 is mounted on a verticallymovable carriage 34 which carries the feeding- device 36 slotted at its lower end to rock and slide on the stud 37. The feeding-device is actuated by a cam 38 on a shaft 39, and is returned by a spring 40, the shaft 39 being driven by universally-jointed connexions from a shaft 58, Fig. 6, which carries.an elliptic gear 60 gearing with a similar gear 61 on the benderactuating shaft 57. In the Figure, the feedcam 38. is for clearness shown mounted on the shaft 58. The gears 60, 61 are so arranged that the feed-shaft 58 is driven at its maximum speed when the bender is depressed between the sewing of two straight stitches to allow the feed to take place, and at its minimum speed when the bender is depressed during the formation of the diagonal stitch. For this purpose the cams 38, 44 are made adjustable on their shafts.