Improvements in thread carrier driving mechanism for straight bar knitting machines
673,979. Knitting. COLTON, L. H. (Thiede, W.). July 8, 1949, No. 18043/49. Class 74 (ii). A straight-bar knitting-machine has a positive thread carrier drive, providing a substantially constant lead of the thread carrier or carriers in front of the slurcock, in which a coupling device for engaging and disengaging a thread carrier rod to and from the slurcock bar comprises an element movable along a cycloidal path during engagement to achieve substantially shock-free acceleration of the thread carrier rod at the commencement of its travel and movable along a cycloidal path during disengagement to achieve substantially shock-free retardation of the thread carrier rod at the end of its travel. As slur bar 1 begins to move to the left, pinion 7, which is carried with it, rolls along rack 15 and is rotated clockwise through 90 degrees. During this rotation, roller 6 enters behind member 9 and moves thread carrier rod 2 with increasing speed until, when crank-arm 5 is horizontal, bar 2 is moving at the same speed as bar 1. Towards the end of the traverse, pinion 7 engages rack 16 and is rotated through a further 90 degrees to release member 9 by means of a bar 24. Rack pairs 15-17 and 16-18 are now raised whilst the slurcock is stationary, so that, as the reverse traverse begins, pinion 7 rolls along rack 18 through a third 90 degrees to enter pin 6 behind member 11 and accelerate rod 2 up to full speed and, as the traverse is ending, rolls along rack 17, through a final 90 degrees to disengage pin 6. Racks 15, 17 and 16, 18 are moved, during widening or narrowing, by means of rods 26, 27.