l78 THANS ACTIONS OF THE 



of the bed plate. The connecting rod 28, and the short arm 26, 

 the needle arm 29 and the fixed arm 19, are adjusted at right 

 angles to the lines of 4 and 21. The rotating hook 5, is a portion 

 of the thread of a screw formed upon the periphery of the circu- 

 lar concave disk. 



To the left of the notch rf, is a portion of another parallel 

 thread of the screw. The disk is cut away below the point rf, 

 into its concavity, so that the thread of the screw forms the clear 

 point ot the hook a. The groove between the two threads of the 

 screw extends diagonally across the periphery of the hook disk to 

 the point &, where the hook thread of the screw is entirely cham- 

 fered off, and the groove disappears. The two concave surfaces of 

 the disk and the slide ring 16, contain the bobbin 15. The 

 needle 35 is curved to the arc in which the end of the needle arm 

 vibrates. A perfectly rectangular figure is formed ; the arbor 4, 

 forms one side; the connecting rod 28, a second; the rocker 24, 

 the third; and the needle arm with the needle 35 and the rotary 

 hook 5, the fourth. The opening is made for sewing between the 

 needle and the hook. 



The working parts are secured to a frame constituted by the 

 bed plate 1,1, and the standard 2, 2, and 3, 3. The slide ring 

 16, is adjusted by the set screw 53, to retain the bobbin 15, and 

 allow it to turn freely in the concavity of the hook disk. The 

 needle 35 is adjusted with its head in the needle yoke 34, to 

 vibrate through a small hole 60, in the cloth plate 46, and so 

 that the point in its rise will bring its eye just below the point of 

 the hook a, which revolves so close by the side of the needle 35, 

 that nothing can lie between them as they come opposite each 

 other. The eccentric ring 8, through the connecting rod 28, and 

 the rocker 24, vibrates the needle arm so that it begins to rise 

 just before the point of the hook reaches the needle. 



^'g- ^^- The pressure of the fabric upon the 



thread about the needle as it begins to 

 rise, loops the thread slightly upon 

 1 '^^^^^^^^^ ^ the right of the needle. This loop is 

 caught, enlarged and carried around 

 the bobbin, as before illustrated. 

 When the loop of thread is about to 

 slip from the hook, as represented in 

 fig. 10, it is checked for an instant until 



