GB249969A - Improvements in trimming mechanism for sewing machines - Google Patents

Abstract

249,969. Armstrong, J. J. V., (Union Special Machine Co.). Feb. 4, 1925. Trimming - mechanism for sewing-machines comprises a movable blade kept in alignment with a stationary blade by a device contacting therewith and mounted independently of the movable blade on the carrier thereof. The mechanism comprises a movable blade 30 and stationary blade 26. The blade 26 is are shaped and is secured in a recess in a bracket 22; its upper edge is bevelled as shown at 29, Fig. 7. The movable blade 30 lies in a plane cutting the plane of the blade 26 but its cutting edge 31 is parallel thereto. The blade 30 is carried by an arm 32 mounted on a short shaft and actuated by an arm 39, and link 41 from a rock-shaft 16 driven by an eccentric 20 on the main-shaft 9. The two blades are maintained in alignment by a guide bar 48 secured in a recess 49 in the head 44 of the arm 32 and against the stationary bar by a spring which tends to move the shaft of the arm 32 endwise. The bar 48 is adjusted in the head 44 independently of the bar 30 so that the friction of the latter against the bar 26 may be adjusted to prevent undue wear. Frames.-The trimmed-off material is directed away from the mechanism by a cover-plate 59. A cover-plate 60 for the front of the machine is hinged at 61 and carries a pivoted section 64 held in normal position by a spring 67 surrounding a rod 68 but movable downwardly by a finger piece 70. A catch 71 retains the plates 60, 64 in closed position. Stitch forming and feeding mechanisms are described as set forth respectively in Specifications 241,433 and 249,970.