GB840929A - Improvements in guiding mechanisms for travelling webs - Google Patents

Abstract

840,929. Guiding webs transversely. FIFE, I. L. Sept. 14, 1956, No. 28173/56. Class 100(1) In a web guiding mechanism for a travelling web, a lateral change in path of travel of the web, to restore the web to a desired lateral path as a result of a lateral deviation from its path, is caused by a lateral and angular change of position of a guide roller or rollers about which the web is wrapped, a support being provided at each side of the web for the ends of the roller or rollers and each support is slidable in a separate set track and wherein the setting of the tracks can be changed so as to vary the relationship between the lateral movement and angular movement of the roller or rollers with respect to the web. As shown, the web D passes around rollers 10, 12 mounted in frames A each having identical L-shaped brackets 1 and 2 having vertical portions 3 and 4 and horizontal portions 5 and 6 respectively. The portions 3,4 support a shaft carrying the roller 12, while the portions 5, 6 support a shaft 9 carrying the roller 10. The portions 5, 6 have hubs 7, 8'which receive vertical spindles 28, 48 respectively such that the portions 5, 6 can pivot about these spindles. The spindles 28, 48 are threaded into blocks 27, 47 slidable along pairs of rods 25, 26 and 45,46 respectively. The rods 25, 26 are mounted on a plate 20, while the rods 45, 46 are mounted on a plate 40. The block 47 has a threaded bore which receives a screwed shaft 53 secured against axial movement, but rotatable by a pulley 57 and endless belt 58 passing around a driving pulley 88 on a shaft 86. The shaft 86 is driven by a power unit in response to lateral deviations of the web 10 as detected by a sensing member 80. The sensing member 80 has apertures which are covered or uncovered upon lateral movement of the web to vary the pressure exerted on a diaphragm within a unit 70 having a constantly driven cone movable by a lever actuated by the diaphragm into engagement with a pair of cones on the shaft 86 to rotate the shaft 86 in either direction. Since the plates 20 and 40 are inclined to the direction of web travel, deviations of the web from its predetermined path cause tilting of the rollers 10 and 12 as well as lateral movement of these rollers with respect to the direction of web travel, thereby returning the web to its predetermined path.