Yarn feed roller assembly

摘要

A yarn feed roller assembly for a tufting machine pattern attachment including a plurality of hollow drive shafts each having a plurality of feed rolls rotatably mounted thereon. An electromagnetic clutch having a rotating field keyed on the shaft within each feed roll selectively transmits the rotation of the shaft to the roll. Corresponding rolls of the drive shafts are drivingly connected one to the other. Between each pair of rolls is positioned a stationary yarn holding gear having teeth on only a portion thereof which bind with a corresponding gear on the other drive shafts and have yarn receiving grooves for surplus yarn when tufting with less yarn ends than the machine is capable of using. Slip rings located in a group at one end of each shaft receive electrical leads which pass through the shaft center from the clutch field coil. A horse shoe shaped brush retainer rides on each slip ring and is prevented from rotating by a quick release hook member which fits over a securing bar and is held in place by a spring member that also supplies the electrical power to the brushes.