| 摘要 |
870,786. Sewing machines. FILOTECNICA SALMOIRAGHI S.p.A. Nov. 27, 1959 [Dec. 9, 1958], No. 40377/59. Class 112 [Also in Group XXIV]. In a zig zag sewing machine a pattern cam or cam unit is removably attachable to a driving element in any one of a plurality of positions relatively thereto, the cam or cam unit being provided with a graduated scale co-operating with a fixed pointer. As shown, pattern cams 3 are secured by a ring 4 to a sleeve 2 formed with a series of radial slots 5, any diametrically opposed pair of which may be engaged with the curved front ends 7 of a V-shaped spring 6 fixed in a driving shaft 1, when sleeve 2 is mounted on the latter. A graduated scale provided on ring 4 moves past a fixed pointer 4. The graduation opposite the latter is observed when the cam unit is removed if it is desired to recommence the pattern at the required point, the cam unit being then subsequently replaced in the same position relative to the pointer. Alternatively, the cam unit may be re-positioned relatively to the pointer by reference to the appropriate cam diagram which is provided with graduations corresponding to those of the scale on the cam unit, as shown in Fig. 4. |
