Needle selection device

Claim 1

IN A CIRCULAR KNITTING MACHINE, IN COMBINATION, A ROTARY NEEDLE CYLINDER HAVING AN AXIS AND AXIALLY EXTENDING GROOVES; NEEDLES DISPOSED IN SAID GROOVES FOR SLIDING MOVEMENT; JACKS MOUNTED IN SAID GROOVES FOR LIFTING SAID NEEDLES, SAID JACKS HAVING BUTTS DISPOSED AT EIGHT CIRCUMFERENTIAL LEVELS, A FIRST GROUP OF FOUR JACKS HAVING BUTTS AT FOUR ADJACENT LEVELS LOCATED ALONG A FIRST CIRCUMFERENTIAL ARC, AND A SECOND GROUP OF FOUR JACKS HAVING BUTTS AT FOUR OTHER ADJACENT LEVELS LOCATED ALONG A SECOND CIRCUMFERENTIAL ARC, EACH GROUP OF JACKS HAVING SHORT BUTTS OF THE SAME LENGTH AT THE RESPECTIVE FOUR ADJACENT LEVELS, AND EACH JACK OF EACH GROUP HAVING ONE LONG BUTT, SAID LONG BUTTS BEING LOCATED AT DIFFERENT LEVELS AND ADAPTED TO CAUSE THE FORMATION OF TUCKSTITCHES BY THE RESPECTIVE NEEDLES, SELECTED BUTTS OF SAID SHORT BUTTS BEING ADAPTED TO BE OMITTED FOR FORMING A SELECTED PATTERN DIFFERENT FROM THE TUCK STITCH PATTERN; A STATIONARY STRUCTURE INCLUDING A SUPPORT; EIGHT SLIDER CAMS INCLINED TO THE AXIS OF SAID NEEDLE CYLINDER AND TO SAID LEVELS, AND MOUNTED ON SAID SUPPORT AT SAID LEVELS, RESPECTIVELY, FOR MOVEMENT BETWEEN A RETRACTED POSITION AND AN OPERATIVE POSITION FOR ENGAGING SAID BUTTS AT THE CORRESPONDING LEVELS FOR LIFTING THE RESPECTIVE JACKS AND NEEDLES; AN ASSEMBLY OF COAXIAL ROTARY CAMS SUPPORTED ON SAID STRUCTURE FOR TURNING MOVEMENT ABOUT AN AXIS PARALLEL TO SAID AXIS; CAM FOLLOWER MEANS CONTROLLED BY SAID ROTARY CAMS AND RESPECTIVELY ACTING ON SAID SLIDER CAMS, SAID CAM FOLLOWER MEANS INCLUDING TWO SETS OF EIGHT CAM FOLLOWER LEVERS, RESPECTIVELY; A SHAFT SUPPORTING SAID CAM FOLLOWER LEVERS AND BEING PARALLEL TO SAID AXIS OF SAID NEEDLE CYLINDER, THE CAM FOLLOWER LEVERS OF EACH SET ALTERNATING WITH THE CAM FOLLOWER LEVERS OF THE OTHER SET, EACH CAM FOLLOWER LEVER BEING CONTROLLED BY A CORRESPONDING ROTARY CAM, TWO ADJACENT CAM FOLLOWER LEVERS OF SAID TWO SETS CONTROLLING THE SAME SLIDER CAM FOR SHIFTING THE SAME BETWEEN SAID POSITIONS; AND MEANS FOR PREVENTING OPERATION OF SAID SLIDER CAMS BY ALL THE CAM FOLLOWER LEVERS OF EACH SET.