Circular knitting machine

Claim 1

FOR A CIRCULAR KNITTING MACHINE COMPRISING AN AXIALLY SLOTTED NEEDLE CYLINDER MOUNTING A PLURALITY OF RADIALLY BUTTED NEEDLES THEREIN, A CAM BOX CIRCUMSCRIBING SAID CYLINDER AND POSITIONED TO ENGAGE THE BUTTS OF THE NEEDLES, AND MEANS TO CAUSE RELATIVE MOVEMENT BETWEEN SAID CAM BOX AND SAID CYLINDER THEREBY EFFECTING AXIAL MOVEMENT OF SAID NEEDLES TO AT LEAST ONE OF THREE LEVELS: STITCH CLEARING, TUCK AND STITCH DRAW; A RISER CAM IN SAID BOX HAVING A BODY PORTION AND A NEEDLE RISING SURFACE FOR ENGAGEMENT WITH THE BUTTS OF SAID NEEDLES, SAID NEEDLE RISING SURFACE BEING OF SUFFICIENT LENGTH TO RAISE SAID NEEDLES TO AT LEAST A CLEARING HEIGHT, SAID RISING SURFACE HAVING A GAP BELOW THE TUCK LEVEL, AND A NEEDLE BUTT GROOVE EXTENDING FROM SRAID GAP THROUGH SAID BODY PORTION, SAID GAP AND NEEDLE BUTT GROOVE HAVING AN AXIAL HEIGHT AT LEAST EQUAL TO THE AXIAL HEIGHT OF THE NEEDLE BUTTS, A RADIALLY-MOVABLE FIRST SLIDE CAM DIMENSIONED AND NORMALLY POSITIONED TO BRIDGE SAID GAP SO AS TO PROVIDE IN CONJUNCTION WITH SAID RISING SURFACE A SMOOTH, UNINTERRUPTED NEEDLE RISING SURFACE, A SECOND RADIALLY-MOVABLE SLIDE CAM HAVING A NEEDLE CAMMING SURFACE AND POSITIONED SUBSTANTIALLY PARALLEL TO SAID FIRST SLIDE AND INTERSECTING SAID NEEDLE BUTT GROOVE, SAID SECOND SLIDE HAVING A LENGTH ALONG ITS CAM SURFACE SUFFICIENT TO RAISE NEEDLES TO A TUCK LEVEL.