GB1248059A - Method and apparatus for the production of pile fabrics - Google Patents

Abstract

1,248,059. Tufting machines. MOHASCO INDUSTRIES Inc. 18 Nov., 1968 [16 Nov., 1967], No. 54570/68. Heading DIG. [Also in Division G3] Patterned yarns are fed to a tufting machine in zones, the yarns from one beam being used for one zone, one yarn in each zone being an index yarn which is sensed by a photocell arrangement and its position relative to a similar index yarn in a master zone checked so that speed variation in a slave zone can be effected, if necessary, or the machine stopped in extreme cases to ensure that the pattern across the whole fabric is maintained in transverse alignment. The index yarn Y (Fig. 4) comprises white and black patches along its length and two photocells 114 and 115 sense the yarn as it passes. If as shown in the circuit in Fig. 6 for example both the master zone photosensors 114b' and 115b' detect a dark zone in their index yarn and in the slave zone only one slave photosensor detects a dark zone then the slave zone yarns are going either too fast or too slow relative to the master zone yarns. The master logic decoder sends a speed evaluate pulse to the slave logic decoder and a reset attempt pulse to the reset gate when both master sensors detect a black index mark. The slave logic decoder applies a yarn slow pulse to the clutch selector and an accelerate clutch 13 engaged which connects the yarn feed with a faster moving shaft when only the first slave photosensor-114b senses an index mark when the speed evaluate pulse is applied from the master logic decoder. Similarly if only the second photosensor 115b detects the index mark the retard clutch is connected. If all four sensors are activated the average clutch is maintained or reselected. If neither of the slave photosensors detect the index mark a no-go pulse is passed to the alarm and a reset inhibit pulse to the reset gate which will maintain the clutch previously selected at that same state until corrective action is taken by the operator.