GB684312A - Improvements in or relating to methods and apparatus for gripping and cutting off the inactive threads in straight-bar sinker operated knitting machines - Google Patents

Abstract

684,312. Knitting-machines. BATA, NARODNI PODNIK. Aug. 19, 1948. [Sept. 4, 1947] No. 21903/48. Class 74 (ii). In a straight-bar machine, as hooks pull threads being taken out of action into V-shaped loops, an associated clamping and severing device advances in the direction of sinker projection, towards the loops being formed, putting into operation means for introducing between the clamping jaws, clamping and severing one branch of each loop and then retracts, restoring the means to the initial position. A thread taken out of action is pulled into a loop by the lower hook end 59 of the associated one of levers 58 pivoted as at 62 and carried on one or other of reciprocating bars 64, 65. If a thread guide is arrested, for example at the right side of the needle bank, the upper end 57 of the appropriate lever 58, during movement of bar 64 to the left, slides on the surface of a flat spring 56 to locate the hook 59 beyond and behind the tube of the idle thread guide. As the bar 64 reverses, the end 57 slips off the spring 56 and under the action of a torsion spring 60, snaps on to a guide 55, whereby the hooks 59 grasps the thread. During the reverse travel of bar 64, the hook 59 draws out the thread into a loop and the end 57 passing under the free end of the fiat spring 56 and riding up the. bent end of guide 55, the hook 59 is finally rotated away from the loop it has formed. Each pair of clamping jaws 11, 14 and knife 26, which co-operates with the lower jaw 11, are carried on a body 10 advanced by action of a cam member 19 on a pin 17 on the body and are retracted by a spring 24, the member 19 being carried on a reciprocatable bar 21. As the body 10 advances during the above loop drawing operation the knife 26, pivoted at 27, is raised by the coaction of a pin 29 thereon with the upper face of a cam member 33 and where the pin subsequently rides off member 33, is snapped down by a spring 30, to sever the upper branch of the loop of yarn which has been gripped between the jaws. The upper leg of the loop is guided between the jaws by the enlarged end 49 of a pivoted lever 47 rocked, against the action of a spring 52, by a lever 42, a pin 41 on which rides in a cam groove 40 in the body 10. The bars 64, 65, 21 are reciprocated, through levers 70, by a cam drum keyed to a shaft 76 and rotated from the main cam shaft 5, through chains and sprockets and a single revolution clutch. In the idle position of the clutch, a constantly rotating pinion is opposite a gap in the teeth of a gear wheel 104. The wheel 104 is located in this position by a spring-pressed plunger III which engages in a recess 1101 in a disc rigid with the wheel 104 and also in another recess in,the limb of a sector 93 freely rotatable with respect to wheel 104 and held by pin 95 and notch 94 against a spring 103 which urges the sector in a clockwise direction. As a control drum 122 is stepped round, a projection 123 thereon, acting through linkwork, raises the pin 95 from the notch 94, whereupon sector 93 is rotated clockwise, a pawl 97 thereon sliding on the periphery of disc 106 and into a recess 110 thereon. This rotation has lifted plunger 111 and has placed the sector 93 in the path of a pin 118 rotating with the pinion 114. This pin 118 rotates the sector 93 counter-clockwise and hence, through pawl 97 and disc 106, rotates wheel 104 so that its teeth now engages those of pinion 114 and it is rotated through one revolution, as is also the cam drum which is driven by a pawl on sprocket 83. Meanwhile, the sector 93 has been released and has again performed clockwise and counter-clockwise swings, under the influence of a spring 103 and pin 118, to be arrested in its idle position by plunger 111 and to be locked therein by pin 95 as, the drum 122 being rocked again, the lever 124 slips down projections 123.