GB190900266A - Improvements in Shuttles for Sewing Machines. - Google Patents

Abstract

266. Bates, H. A. Jan. 5. Sewing-machines; lock-stitching by shuttles. -In a shuttle which comprises a bobbin-case holder and a separable bobbin case and thread bobbin, a volute spring is provided between the bobbin and the bobbin case and in front of the bobbin, which spring acts expansively to separate the parts when the bobbin case is released. The bobbin-case holder a is provided with a central tubular pin a<2>, slotted at one side, having its outer end pivotally connected to a locking-lever b. The inner end of this lever is bevelled so that it is held in either of its two positions by the spring-pressed plunger 4. The bobbin-case c has a central aperture c<1>, through which the pin a<2> passes, and is provided with a volute spring d, the large base convolution 5 of which is held frictionally in the base angle of the bobbin-case. The spring is coiled for compression in the direction of the axis, and normally fills more than half the case. The thread bobbin f, when placed in the case, presses the spring practically flat, and the bobbin and case, when placed on the pin a<2> of the holder, are held in connexion by the turning into the full-line position, Fig. 4, of the lever b. When this lever is turned to the dotted-line position, the spring d immediately causes the partial separation both of the case-holder and the case, and of the case and the bobbin.