Patent GB-190718052-A (GB)
Title: An Improved Method of and Apparatus for Sewing.
Inventor: BAKER FREDERICK
Filed: 1907-08-08
Granted: 1908-11-09
Abstract: 18,052. Baker, F., and Jacobs, L. Aug. 8. Loop-stitching g machines.-A single-thread stitch is formed by drawing a long loop from the needle, and knotting it with one or more sub-loops or locking it with two or more sub-loops, from the same supply, to form stitches until the end of the long loop is reached, the needle thread then being passed through the bight of the long loop f and a new long loop formed and secured to the previous one. The operations may be effected by the disk D, Fig. 2, arranged on a spindle below the bed-plate of the machine. The disk carries a rocking member d', pivoted at d<2> and gearing with a quadrant d<7> which carries a cam d'. The cam engages with projections d<5>, d<6> of a bridge-piece G carried by the bearing-plate H so arranged that the engagement with the projections d<5>, d<6> throws the hook d<x> outwards and inwards respectively. The disk also carries a thread-guide d' and has camgrooves d
, d<9>, on its back face, which operate the members d<10>, d<11> during the rotation. Upon the periphery of the disk there bears a device E, comprising a casing c and a sliding or rocking hooked member e<1> controlled by a spring e<3> in a groove thereof, and having a projection e<4> normally engaging with an arm e<5>. As tha needle A descends through the material, the hook d<x> engages the thread and carries it round until the projection d<6> causes the member d' to assume its outward position, when the thread escapes from the hook and passes over the device E underneath the members d'‹, d<1> which are at this moment successively operated by the cams d<8>, d<9> to allow the thread to pass between them and the device E. The loop is then arrested by the hook e<2>, being directed thereon by the guide e<x>. In the further movement of the disk, the member d' is moved inwards by the projection d<6>, and a guide-bar dx<1> prevents it from flying out during its upward movement. The needle having meanwhile again descended, the hook pulls another loop round, and this loop in turn slips over the device E, but owing to the lug d making contact at this stage with the projection e<5x> of the arm e<5>, which is thus lifted clear of the projection e<4>, the loop is not caught by the hook e<2> but is pulled by the take-up over the first loop taut against the material. Several of these latter stitches may be formed on the first loop, until the feed of the material moving forward causes the loop to overcome the tension of the spring e<3> and escape the hook, after which it is held by the spring e<6>, in which position it is held until the needle descends through it and forms a new long loop screwed to the first. As this new loop is drawn tight by the take-up, the first one escapes the spring e<6> and is drawn up to the work. In a modification, the disk is replaced by an oscillatory quadrant D, Fig. 15, provided with a hook d<2>, and the device E enters a groove in the periphery of the quadrant, the lugs d<10>, d<11> of the lever D <x> being in this case operated by the cam d<a>. Instead of the piece e<1> carrying the hook e<2>, a chain carrying a hook or hooks may be placed in the groove of the device E. The stitch formed is shown in Fig. 1, but by causing the needle to descend at the side of the long loop and then throwing the subloops over as before, an alternative form of stitch is made. Needle-driving; governing needle thread.-To obtain two or more loops for each revolution, the needle mechanism is modified to give two or more perforations for one revolution of the disk, for which purpose the needle-operating shaft F, Fig. 17, is provided with a collar f having cam-grooves f<1>, f<2>, A bar f<3> is reciprocated by the cam f<1>, and imparts a rocking movement to the take-up lever f<4>, while the cam f<2> operates the pivoted rocking lever f<7>, which is adjustably connected to the needle-bar ; the groove f<2> is shaped, as shown, to give the needle two or more descents for one revolution of the shaft F. The parts of the stitchforming mechanism on the disk serving to engage the needle thread are repeated at intervals on the disk to act in conjunction with the mechanism. Work-supports.-The needle-plate B is made as thin as possible and may be recessed, as shown, to bring the work nearer to the needle.