GB832291A - Loop-taker for lock stitch sewing machine - Google Patents

Abstract

832,291. Sewing machines. SINGER MANUFACTURING CO. Dec. 6, 1957 [Dec. 31, 1956], No. 38017/57. Class 112 In a thread-case for a lockstitch sewing machine looptaker comprising a cup-shaped member formed in its base with an aperture through which thread from the centre of a cop can be delivered, thread - controlling means mounted on said base include a member which enters said aperture to form a restricted opening for preventing the passage of kinked thread therethrough, and a thread-tensioning member situated adjacent said aperture for pressing the thread emerging from the latter against said base. A substantially semi-circular member 15 formed with a loop-seizing beak 18 has a peripheral rib 19 journalled in a raceway 20 provided in a fixed housing 14, and is oscillated by a shaft 21 having a dog member which is adapted alternately to engage the end faces 15n of rib 19. The thread casing assembly comprises two cup-shaped interfitting parts, namely, a thread-case holder 23 and thread-case 24. A hub 28 on the latter is journalled in member 15, and is retained in the latter by a screw 30 which is threaded through hub 28 and by a washer 32 which is interposed between the tapered head 31 of screw 30 and member 15. A leaf spring 35 secured to the side wall of holder 23 is provided at one end with a protuberance 37 which passes through an aperture in said wall and enters a peripheral groove 42 in the side wall of case 24 to retain the latter releasably within holder 23. The base of case 24 is formed with a diametrical groove 49 pierced by a thread-massing aperture 47. A threading slot 48, which passes through said base, extends radially from aperture 47 and a thread-receiving notch 58 is formed adjoining the latter. A plate 53 is disposed in groove 49 and is overlaid by a leaf spring 59. A screw 62 passes through plate 53 and spring 59 to secure these within groove 49, and a screw 60 passes through spring 59 to vary the pressure exerted by the latter on plate 53. Said plate and spring are narrower than groove 49 to provide a thread-passing passage 56 at one side of the latter. A stud 54 projects from plate 53 into aperture 47 to provide an annular thread-passing opening 55. Thread t passes from the centre of a cop C through opening 55 and notch 58 to be pressed between plate 53 and the base of groove 49. The thread passes around screw 62 to be directed thereby into a thread-guiding notch 64 formed in a plate 63 fixed to the side wall of case 24. A rib 43 which extends outwardly from the base of the latter is formed with a cranked end portion 44 which enters a notch 45 in housing 14 to prevent rotation of case 24, and with a finger slot 46 to facilitate insertion and removal of case 24. The edge of rib 43 is semi-circular to facilitate the shedding of the needle-thread loop thereover.