GB1166786A - Apparatus for Edge Trimming Fabrics - Google Patents

Abstract

1,166,786. Trimming fabrics. RIGGS & LOMBARD, Inc. 16 May, 1968, No. 23258/ 68. Heading D1S. Apparatus for trimming threads 16 formed along the edge 14 of a fabric web 10 comprises a rotary shearing head 38 of a length substantially less than the width of the web 10, the head 38 .being mounted for rotation about an axis perpendicular to the longitudinal movement of the web 10 and parallel to the plane thereof, means for advancing the web 10 to carry the edge 14 into shearing contact with the head 38, and guiding means to maintain the edge 14 and the head 38 in predetermined relation. As shown, the web 10 is woven on a shuttleless loom and has a straight selvedge 12 with no loose threads and a selvedge 14 formed with a fringe 16 of bulky threads to be removed. The trimming apparatus comprises a carriage 20 horizontally movable along fixed supports 22, 24. Two rotary shears 38 are mounted on the carriage 20 to extend one on each side of the web 10 and are each driven by a motor 42. A ledger knife 44 is mounted on the same side of the web 10 as each shear 38 and a fabric rest 46, 48 is provided on the opposite side of the web to each shear 38. Each rest 46, 48 is provided with a nose portion 50 movable into and out of fabric-engaging position by a lever 52. A web edge sensing head 53 is mounted on the carriage 20 ahead of the first shearing unit and includes leg portions 54, 56 to span the margin of the edge 14. Compressed air passes through a conduit 58 and is directed downwardly against the selvedge 14. A slot is formed in the portion 56 and communicates, through a conduit 60, with a control unit 59. Movement of the edge 14 causes a change in the pressure to a diaphragm 62 which is displaced to or from a hydraulic relay 64 controlling a valve 66 which directs fluid to either end of a hydraulic cylinder 68 the piston rod 74 of which shifts the carriage 20 so that the shears 38 follow the edge 14. The sensing head 53 is adjustable in position so that all of the cutting action is not done by one small section of the shears 38 and knives 44. The sensing head 53 may be adjusted to jog continuously back and forth slightly. Air nozzles 78 80 direct air towards the edge 14 from positions inboard thereof to blow the threads 16 into cutting position. A wireclothed brush 82, Fig. 8, having bristles helically mounted thereon, may be provided and is rotated over the edge 14 to brush the threads 16 outwardly. A substantial portion of each shear 38 may be enclosed by a hood 84 connected by a conduit 86 to a suction source. For trimming terry loop fabrics, a mask (88), Fig. 9 (not shown), prevents the pile of the fabric from being sheared. If the fabric is accidentally cut through, a trip (90), Fig. 6 (not shown), normally held in raised position by the fabric, drops through the cut opening and pivots a finger (94) against a microswitch (96) to stop the fabric feed.