Patent GB-409158-A (GB)
Title: Feed-off-arm sewing machine
IPC: D05B57/14
Filed: 1933-07-01
Abstract: 409,158. Sewing-machines. FAIRWEATHER, W. C., 65, Chancery Lane, London.- (Singer Manufacturing Co.; Elizabeth, New Jersey, U.S.A.) July 1, 1933,No. 18707. [Class] 112.] Relates to feed-off-arm sewing-machines of the type described in Specification 361,533. Lock-stitch machines. In a feed-off-arm machine the needle bar 24 carries two needles 25 co-operating with two rotary loop-takers 73, Fig. 3, which are driven from a cross shaft 50 by bevel gears 54, 55, parallel shaft sections 123, inclined shaft sections 125, parallel shaft sections 104 and bevel gears. The shafts run in sleeves which are clamped in split sections of adjustable bearing block 598. The cross shaft 50 is driven by belt from the top shaft 9, and the belt case has a detachable inspection plate. The construction of the loop-taker and bobbincase mechanism is that described in Specifications 409,159 and 409,161. The throat plate 61, Fig. 4, has a depending post 151, Fig. 4, grooved at 152 alongside the needle paths to assist in bowing out the needle loops. Feeding work. The feed-dog 62 is mounted on a feed-bar 63 fulcrumed to rock and slide on an adjustable pin 64. The feed-bar has a vertical fork 67 embracing the block of an adjustable feed-advance eccentric 56, and an attached bar 70 having a horizontal fork 71 embracing the block of a feed-lift eccentric 57. Thread cutters. On the end of the arm 3 a razor-like double-edged blade 147, Figs. 7 and 10, is clamped between a block 142 and a plate 144 both of which are formed on their upper edges with registering grooves 146. Should a needle-thread break, the work in falling off the arm draws the bobbin-thread into contact with the blade 147 and severs it, thus preventing wastage. Frames. The screw bolts 158 which enter holes 157 in the bed-arm 1, Figs. 3 and 25 to secure it to the table 160, pass through rubber or felt bushings 159, and a layer 161 of rubber or felt is placed between the table and the bed-arm. The bolts are locked by set-screws 162. The type of goose-neck 5 may be changed in order to produce a different type of seam. Chain-stitching. A modification is described in which the needle-bar having two needles abreast co-operates with twin threaded loopers to form double-loop stitching. The general lay-out of a feedoff-arm machine comprising a feed-bar 219 is the same as is described above. The twin loopers 231 are carried by a shaft 230 to which a rocking movement is imparted by an eccentric 232 on the cross shaft 216, and an endwise movement is imparted by an eccentric 239. The connections comprise a rocking lever 235 on one side and a slide rod 242 on the other. A looper-thread controlling cam 247 is mounted on the shaft 216 and co-operates with a stripper blade 248 and a thread-nipper 250. The threads are led to the loopers by a channel 252 and a tube 253. Lubricating. The mechanism associated with the needle-bar 24 is lubricated as described in Specification 409,160, and the bobbin-case races within the rotary loop-takers are lubricated as described in Specification 409,161. The mechanism driving the feed-bar and the loop-takers is lubricated by splash from an oil sump in the base of the arm 3, baffle-plates being arranged to prevent splashing of the feeddog and thread bobbins. Oil from the upper driving-mechanism drains into a sump 156, Fig. 3.