GB121700A - Sewing Machine. - Google Patents

Abstract

121,700. Fairweather, W., (Singer Manufacturing Co.). July 4, 1918 Blind-stitching machines. - Described in connexion with a machine comprising a horizontally reciprocating needle - bar 7, Fig. 2, and oscillating locptaker shaft 12 mounted in a pivoted frame 5 which is oscillated about its pivot 6 once for each two stitches, the needle-bar being actuated by a crank and pitman 13, 14 and carrying a cross-head 15 threaded to engage a worm on the loop-taker shaft; a presserfoot 138 pivoted on a spring-pressed rod 136 carried in a tube 141 having a trunnion 142 which is free to slide axially and oscillate in its socket under the control of a spring 146; a needle guard 155 sliding in the tube 14 and reciprocated bv a bell-crank lever actuated by a cam on the needlebar; a work-bender 116 reciprocated by a lever 112, actuated through a buffer spring 123, from a cam-actuated lever 107. The work is supported by a frame 66 guided vertically by pins 85, 86 on the lugs 84, 85 of a fixed bracket and movable downwardly by rocking an arm 29 journaled on a transverse feed-actuating shaft. Feeding mechanism mounted in the frame comprises a feed-dog 70 carried on rods 71, 72, Fig. 8, rising from a yoke member 73, and slicing in a cross member 75. A lever 76 is pivoted on the frame and is pivoted to the member 75 at one end, and at the other end is provided with a yoke 76<1>. Springs 79 are placed on the rods 71. 72 and interposed between the yoke 73 and cross member 75. The rising and falling and feeding movements of the feed dog are obtained by two cams 68, 69 on a shaft 24 which passes through the arm 29 and carries a bevel gear 39 driven by one or other of two bevel gear wheels 37 on an actuating shaft at rightangles to the shaft 24. The gear wheels 37 are loose on the actuating shaft and either may be connected thereto by a manually-controlled sliding clutch to drive the feed in either direction. Cooperating with the under feed-dog, and at the delivery side of the presser foot only, is an upper feed dog 166, Fig. 7, carried by a bar 163 pivoted at one end of a cam-actuated lever 159 from which it derives its feeding movements. The forward end of the feed-bar is supported by a spring- pressed rod 184 carried in a tube 182 pivotally mounted in the one end of a bell-crank lever 178 supported on a fixed bracket 176. The bell-crank lever is actuated to communicate rising and falling movements to the feed-dog 166 by a cam-actuated lever 168 with which it is connected by a two-armed connexion 172. The upper feed may be suspended at the will of the operator by swing- ing a pivoted support on the frame under a pin carried by a bar 196 pivoted at the connexion of the rod 184 and feed-bar. The presser-foot is provided with a thread-guard 187, Fig. 12, to prevent the loops of thread becoming entangled with the upper feed-dog, and may also have a ridge 148' on its under side to hold the work against lateral movement during the cloth-piercing movement of the needle.