Patent ID: 7607322
Filing Date: 2009-10-27
Classification: D04B

Abstract:
1. A circular knitting machine, comprising: a cylinder; needle cams disposed about the cylinder and defining a cam track having cam surfaces; knitting needles having needle butts engaged in the cam track such that relative rotation between the cylinder and needle cams causes the needles to be raised and lowered by engagement between the cam surfaces and needle butts; sinkers disposed about the cylinder, each of the sinkers having a first sinker butt; a sinker cam ring disposed about the cylinder and comprising a plurality of sinker cam segments arranged edge-to-edge to form the sinker cam ring, the sinker cam ring defining a first sinker cam track having first working surfaces that include first sinker-advancing surfaces and first sinker-retracting surfaces, the first working surfaces being made up of linear portions and curved portions, the first sinker butts being engaged with the first sinker cam track such that relative rotation between the cylinder and sinker cam ring causes the sinkers to be advanced inwardly and retracted outwardly relative to the needles by engagement between the first working surfaces and first sinker butts; wherein for each sinker cam segment that has the breaks located in the working surfaces defined by said cam segment, said breaks are located in the linear portions of the first sinker-advancing surfaces and/or first sinker-retracting surfaces, where substantially only frictional forces act on the sinkers and radial acceleration of the sinkers caused by the working surfaces is substantially zero.