Patent GB-845139-A (GB)
Title: Improvements in or relating to looping machines and methods, and knitted fabrics seamed thereby
IPC: D05B7/00
Filed: 1958-01-29
Abstract: 845,139. Stitched seams, sewing machines. SCOTT & WILLIAMS Inc. Jan. 29, 1958 [Feb 15, 1957], No. 2931/58. Class 112 Stitched seams, linking machines. A linking machine comprises means for projecting a line of thread loops through superposed layers of knitted fabric, and means for sewing said layers together by passing stitch loops through said layers and through said projected loops. The arrangement is designed to render unnecessary the engagement of consecutive loops of the knitted fabric with consecutive points of the dial prior to stitching, but to enable the .fabric to be run in random fashion on to the points. A linking machine having a rotary ring dial 1 provided with spaced radial points 2 and mounted on a circular bedplate 5, a sewing needle 3 threaded with yarn Y, a looper threaded with yarn Y<SP>1</SP> for co-operation with the needle, and a driving shaft 10, is provided with auxiliary mechanism 25 for projecting a line of loops L, L<SP>1</SP> of yarn Y<SP>2</SP> through layers F, F<SP>1</SP> of knitted fabric. Said mechanism comprises a bracket 26 secured to plate 5 opposite a fabric guard 15 and ahead of a trimming knife 16. The latter is carried by an arm 17 oscillated from shaft 10 via a link 19 and a crank disc 20. A vertical spindle 28, journalled in bracket 26, is oscillated from shaft 10 via gears 29, 30, a shaft 31, an arm 32, a link 33 and gears 36, 39, the latter being arranged to impart several oscillations to shaft 28 for each rotation of shaft 10. An arm 40 on shaft 28 carries a curved needle 41 which is threaded with the yarn Y<SP>2</SP> and which passes through a notch 15a in the guard 15 to a position above the points 2. A pawl 42, pivoted to arm 40, is biased by a spring 46 into engagement with a ratchet wheel 43 journalled in a bracket 45 fixed to guard 15. A segmental plate 47 which is fixed to bracket 45 and underlies the points 2, has fixed to one end thereof a spring tongue 50 which overlies points 2 and extends under the axis of wheel 43 to a position rearwardly of notch 15a. The undersurface of wheel 43 is formed with radial teeth 43a of which the number is half that of the ratchet teeth. Plungers 52, 55, mounted in bracket 45, are spring-biased into engagement with the teeth 43a at diametrically opposed positions, a pin depending from plunger 51 being in constant engagement with tongue 50, and the arrangement being such that the latter is thereby positioned respectively above and below the needle 41 at successive actuations thereof. A rod 63, slidable in an extension of bracket 26. carries at its lower end a notched blade 61 disposed above an aperture 47a in plate 47, and at its upper end a pin 68 disposed in a slot 67 formed in one arm of a bell crank lever 65 fulcrummed at 66 on bracket 26. The other arm of lever 65 carries pins 69, 70 which co-act with cams 71, 74 on shaft 28, and the arrangement is such that blade 61 is projected downwardly through aperture 47a at each actuation of needle 41. The superposed layers F, F<SP>1</SP> of the fabric are run on to the points 2 and are pierced by the needle 41 which passes successively above and below the tongue 50. The blade 61 descends to engage the yarn Y<SP>2</SP> near the needle point and to depress the yarn below the points 2, whereby the yarn is looped under a point or points when the needle is retracted, the length of the loops being determined by the tongue 50, and the arrangement being such that several loops L are formed around each point with connecting loops L<SP>1</SP> around succeeding pairs of adjacent points. Finally as the fabric passes the needle 3 and looper 4, loops L<SP>2</SP> will be formed from the yarn Y through the fabric and through the loops L and L<SP>1</SP>, loops L<SP>2</SP> being enchained with loops L<SP>3</SP> of the yarn Y<SP>1</SP>.