GB608898A - Apparatus for feeding webs to textile machines, especially to clip-chain or pin-chain tenters - Google Patents

Abstract

608,898. Feeding webs. HEBERLEIN & CO., AKT.-GES. Feb. 28, 1946, No. 6277. Convention date, March 5, 1945. [Class 38 (iv)] [Also in Group XL (b)] In apparatus for feeding fabric into a textile machine, the movement of angularly movable guiding rollers is controlled by a light beam directed on to a photo-electric cell and influenced by the selvedge. The selvedge is gripped between two rollers 2, Fig. 13, carried in a bracket 14 which is supported on a rotatable spindle 3. The spindle carries a suitably shaped armature 13 between the poles of an electromagnet 15 which tends to turn the bracket 14 against the tension of a returning spring so that the orientation of the rollers, in performing their guiding function, depends on the current flowing. A lighting system 9 directs a beam on to a mirror 4 and thence to a photo-electric cell 8 so that the edge of the fabric 1, intercepting the beam to a greater or less extent, determines the amount of light reaching the cell. A suitable circuit is shown in Fig. 14. A power transformer, having a winding 22 connected across the mains, supplies the heater of a triode 26, the photo-electric cell 8, through a resistor 27 and the lamp 9. The mains voltage is connected directly through the control magnet 15, byepassed by a large condenser 29, to the anode of the triode 26. With this arrangement, increased light reaching the cell 8 causes decreased current flow in the magnet 15, the sensitivity being determined by the potentiometer 28. A heater 18, Fig. 13, may be placed below the mirror 4 to overcome any condensation of moisture. In an alternative form, the mirror is not used, the lamp and cell being on opposite sides of the fabric.