Patent GB-1531361-A (GB)
Title: Apparatus and method for conditioning and calendering circular knit tubular fabrics
IPC: D06C5/00
Filed: 1976-01-20
Abstract: 1531361 Apparatus for calendering and conditioning fabrics F CATALLO 20 Jan 1976 [3 Feb 1975] 02197/76 Heading D1S An apparatus for carrying out straightening or overfeed calendering operations on a circular knit fabric tube 68 comprises a feed strand 5 from which the fabric 68 is fed, oppositely driven control rolls 49, 50, the speeds of which can be adjusted relative to one another and to a predetermined speed of oppositely driven rolls 43, 43 of the apparatus, a steaming station 8 having steaming hoods 61, 61 and a calender station 9 having calender rolls 63, 63 characterized in that a spreader 10 extends from the control roll station 6 to the calender station 9 and comprises two rolls 26 which define nips with the control rolls 49, 50 respectively through which nips two layers of the fabric tube pass and imparted a circumferential feed, a pair of wheels 34, 34 provided on each frame 24 of the spreader 10 which cooperate with the drive rolls 43, 43 to engage the fabric tube from either side thereof to impart to it face drive, and a drive belt 37 mounted on each frame 24 for imparting to the fabric tube an edge drive. The belt 37 extends substantially the full length of the spreader 10 during straightening conditioning of transversely striped or patterned fabric tubes 68 and extends less than the length of the spreader 10 in an overfeed conditioning of plain fabric tubes. The belt 37 also provides the circumferential feed in association with the control rolls 49, 50, spindles 27 and rolls 26. Rolls 49, 50 and feed rolls 43, 43 which are rubber covered are driven from variable speed drive units 51 and 45 respectively. The rolls 49, 50 can be vertically adjusted relative to one another. The speed of the tube face drive, is the norm against which all other operative speed adjustments are made. The spreader 10 has its mid portion drivingly but freely supported by the rolls 43, 43 and can pivot about a transverse horizontal axis lying in a plane therebetween. The spacing of the front ends of the frame members 24 and that of the rear ends is adjustable. The drive to the calender rolls 63, 63 is provided by a variable speed takeoff (not shown) from the main variable speed drive 45 for the rolls 43, 43. The apparatus may include a thermo-fixing station 65 and a fabric take-away conveyor 64 for use with fabric tubes which are made from synthetic fibres such as polyesters or from blends containing a substantial portion of synthetic or polyester fibres. The thermo fixing station includes radiant heaters 66, 68 separately controlled by pyrometers 67, 67. A skew-correcting roll 17 is also provided to correct lateral skew in the fabric tube 68. The fabric is guided to the spreader 10 by a U-shaped bow 31 which may be replaced by two separate oppositely curved bow elements. If, during a straightening calendering operation, the fabric layers become misaligned or bowing of the striping -or pattern occurs the control rolls 49, 50 are driven at a slower speed than the extender rolls 63, 63 to create a fabric tension between the rolls 26 and the calender rolls 63, 63, and then the clutches 52, 53 of the rolls 49, 50 are individually adjusted to relieve the tension as desired to straighten the striping or pattern of either fabric layer and/or to properly align the two layers. The speed of the calender rolls can then be varied to increase or decrease the fabric tension between the control rolls 49, 50 and the calender rolls 63, 63 so that the centre portions of both layers of fabric will be either advanced or retarded to fully straighten the striping or pattern. During overfeed calendering operation the skew-correcting roll 17 is not used and the drive feed roll 15 is driven by a variable speed drive (not shown) at a speed greater than the speed of fabric advance through the spreader 10 to permit the fabric tube to enter into engagement with the spreader 10 with a minimum of tension between the roll 15 and the spreader 10, the belt 37 is shortened, both friction clutches for the control rolls 49, 50 are fully engaged, and the variable speed drives are adjusted to overfeed the fabric relative to the feed at the calender station 9 to allow the tube to become properly steam heated moistened prior to its engagement by the rolls 63, 63.