Patent ID: 7793523

Claim:
A circular knitting machine, comprising: (a) a knitting head fed with yarns and operable to knit a continuous fabric tube, the knitting head comprising: a plurality of needles carried by a rotating cylinder, the needles being movable up and down in vertical channels defined in the cylinder; a stationary base plate; a cam box supported by the base plate and configured to surround a radially outer surface of the cylinder; a plurality of needle cams affixed to a radially inwardly facing side of the cam box opposing the cylinder, the cams interacting with butts on the needles such that the needles are driven up and down as the needles are carried along by the rotating cylinder; (b) a take-down unit receiving the fabric tube descending from the knitting head and operable to flatten the fabric tube; (c) a wind-up and storage unit receiving the flattened fabric tube from the take-down unit and operable to wind the flattened fabric tube into a roll; and (d) a bearing system incorporated into the knitting head and comprising first and second tapered roller bearings surrounding the cylinder and constraining the cylinder to rotate about a vertical rotation axis defined by the bearing system, the first tapered roller bearing being disposed above and vertically spaced from the second tapered roller bearing, the first and second tapered roller bearings comprising: a ring-shaped inner race for the first tapered roller bearing, and a ring-shaped inner race for the second tapered roller bearing, the inner races being affixed to the cylinder for rotation therewith; a ring-shaped outer race for the first tapered roller bearing and a ring-shaped outer race for the second tapered roller bearing, the outer races being secured to the base plate; and a plurality of tapered first rollers captured between the inner and outer races of the first tapered roller bearing, and a plurality of tapered second rollers captured between the inner and outer races of the second tapered roller bearing.