Patent GB-749863-A (GB)
Title: An improved cloth guiding device
Inventor: DURRANT CYRIL LATHAM
IPC: D06C3/00
Filed: 1953-09-25
Abstract: 749,863. Guiding webs transversely. DURRANT & SONS, Ltd., G. Sept. 13, 1954 [Sept. 25, 1953], No. 26415/53. Class 100 (1). A unit for a cloth web guiding device comprises a pair of co-operating parallel rollers arranged at an angle to the direction of travel of the web, one of which is pivotable about an axis spaced from its own to separate it from the other roller, normally urged together to form a nip for and be driven by one edge of the web, a rotatable friction surface, and means, operative only when the width of cloth edge between the rollers exceeds a given amount, for causing the friction surface to come into driven relationship with one of said rollers, the friction surface being so shaped and arranged as to cause the pivotable roller then to be moved out of contact with the other roller so as to release the web. The axes of the rollers are parallel and inclined at a small angle to the transverse direction of the web. The web passes between rollers 11, 12, Fig. 2, the roller 12 being rotatable on a spindle 14 mounted on a frame 15 pivoted to a fixed casting 10 at 16, the rollers being urged together by a spring 17. A semi-circular disc 20 has a friction surface 21 and is rotatable on an arm 22 pivoted at 23, and carries a weight 24. When the web moves too far into the unit, its edge moves a feeler 27 which through a rod 26 moves the arm 22 so as to bring the surface 21 into contact with a disc 19 of compressed fibre coaxial with and rotatable with the roller 11, whereupon, since the web is rotating the rollers 11, 12, the disc 20 is rotated clockwise, and a roller 29 thereon moves downwards a lever 30 adjustable by a screw 34 with respect to a bellcrank 32 so as to rotate the bell-crank. An arm 35 of the bell-crank then moves a roller 36 on the frame 15 to separate the rollers 11, 12 and release the web. The guiding device comprises two units, one at each edge of the web, and when the web is released, the opposite unit draws it in the opposite direction so as to release the feeler, whereupon the disc 20 is moved away from the disc 19 and is rotated by the weight 24 into its original position, the spring 17 thereby being allowed to bring the roller 12 again into contact with the roller 11. The two units thus operate alternately, causing a slight transverse reciprocation of the web so as to keep it to the required mean path. The pivot spindle 37 of the bell-crank 32 carries a rubber bush 49 to cushion the return movements of the frame 15 and disc 20. The units are each mounted on a bush 43, Fig. 4, slidable on a bar 44 and having a strut 45 engaging a rail 46. The two struts 45 are secured one to the upper and one to the lower run of a chain 47, which can be displaced by a hand wheel to adjust the distance between the units. Each casting 10 includes a guard member 42. In another form, the rollers are arranged one above the other, and the upper roller extends at the outer end beyond the lower. A short roller is supported beneath the overhanging end of the upper roller on an arm which is acted on by a spring to hold the short and upper rollers nearly together, and the surface of the short roller is covered with or made of a material having a high co-efficient of friction. The axial length of the short roller is reduced to about half for a large part of its circumference, leaving an arcuate portion of about 100 degrees extent immediately beneath the upper roller. Movement of the web too far into the unit causes it to move into the nip between the upper and short rollers .so as to rotate the short roller, the arcuate portion of which then engages the end of one arm of a bellcrank lever, rotation of which causes the upper and lower rollers to be separated. The rollers may be arranged side-by-side instead of one above the other. The friction surface may be flat and secured to the face of an arcuate member. According to the Provisional Specification, the friction surface 21 is V-shaped and adapted to enter a V-shaped groove in the end of the roller 11.