Patent GB-190311667-A (GB)
Title: Improvements in Sewing Machines.
Inventor: FLANAGAN DENIS
Filed: 1903-05-22
Granted: 1904-07-21
Abstract: 11,667. Flanagan, D. May 22. Lock-stitch hook seming-machines; governing needle thread; governing under thread.-Relates to machines in which an ordinary spool is used for the under thread as well as for the upper thread. The needle thread e, Fig. 2, passes from a bobbin round a usual tension device, and through eyes at the end of take-up levers d<11>, e', to the needle. The lever e' is of the bell-crank type, and is actuated by the lever d<11>, to vary the supply of thread according to requirements. The under thread is carried by a spool j<1>, Fig. 8, which is held in position in a reel case j<11> by a hinged cover i<111>, the thread passing between the cover and body of the reel case, through a slot k<11> in an adjustable spring-controlled plate k<1>, and then between the latter and a lug k. The tension of the thread is regulated by varying the pressure between the lug k and plate k<1>, which form part of or are attached to the cover j<111>, and which project higher than the eye of the needle, so as to prevent the under thread from being caught by the rotating hook e<111>. The reel-case holder f, Fig. 12, is provided with a trunnion f<1> mounted in a bracket f<11>, and is automatically moved into an operative or an inoperative position by the movement of the cloth plate g<1>, a depending arm g<11> of which engages with an extending bracket f<111> of either the trunnion or the reel case. The book e<111> forms a projecting finger of a disc or arm e<1> mounted on a shaft e", which is driven from the main shaft of the machine. The hook catches the needle thread and passes it round the reel case, the thread being bent and held on the hook by a laterally-projecting flange of a steel blade n, Fig. 12, attached to the reel-case holder f, until the hook is opposite to an upwardlycurved projection n' of the blade n, when the thread automatically releases itself. When the thread is passing between the pointed end of the front portion of the holder f and reel case j<11>, the latter is moved into the position shown in dotted lines in Fig. 12, but immediately the thread passes towards the rear side of the reel case the projection n' causes the latter to move back and leave a free passage for the thread at the rear of the reel case, when the take-up levers d<11>, e<1> pull the thread tight. Feed; lock-stitch shuttle sewing-machines.-Tbe feed is effected by the serrated edges of a feeddog o<111>, Figs. 14 and 15, which projects through a slot in the work-plate g<1>, and which is carried by one of two arms o' projecting from a sleeve o mounted on an eccentrically-turned boss of the disc l which carries the hook l<111>. Mounted between the arms o<1> is a spindle o<11>, on which is loosely mounted a ball p, embedded in one end of a pivoted lever p', the other end of which is provided with a pin q. The latter, or an antifriction roller carried by it, engages with a camgroove in a loosely-mounted and rotatable disc q<11> on the underside of the bed-plate a, and, by turning the disc q<11>, the ball p slides on the shaft o<11> so as to vary the position of the lever p<1> as indicated by dotted lines in Fig. 15, thereby altering the traverse of the feed dog o<111>. Preferably, the disc q<11> is turned by a pin r, which projects through a slot in the work-plate, and which shows on a graduated scale at the edges of the slot the number of stitches per inch to be put into the work. The feed-mechanism, and some of the other improvements, may also be employed in shuttle sewing-machines.