GB1284924A - Thread brakes - Google Patents

Abstract

1284924 Weft thread brakes; shuttleless looms SULZER BROS Ltd 19 Sept 1969 [23 Oct 1968] 46355/69 Heading D1E A thread brake is made up of two cooperating elements 2 and 3a, b or c, element 2 being resiliently deformed by element 3a, b, c and comprising a layer of resilient material 12 with a flexible overlay 11 whose surface has greater wear resistance to the passage of the thread than the resilient layer. As shown an e.g. polyether underlay 12 is placed in a channel shaped beam 4 which is adjustably mounted in a yoke 1 mounted on the loom and eyes 14, 14' at its ends which guide the yarn. The overlay is e.g. of hardened steel and has openings through which pins 9, 9' secured in beam 4 project. The brake elements 3a to c are secured on a common shaft 18 and can be adjusted so that their braking surface, which have an abrasion resistant surface e.g. of aluminium oxide, are at different distances from overlay 11. Shaft 18 is carried in bearings in yoke 1 and one end extends beyond the yoke and carries a loosely pivotable lever 21 secured to it by a catch. Lever 21 is connected by connecting rod 28 slidable in guide member 29 to an adjustable pivoted follower lever 33 carrying a roller 36 which engages a cam 37 splined on a shaft 38 driven from the loom. In operation, the yarn, which passes from eye 14 to eye 14 between pins 9, 9' is controlled by cam 37 so that it is released when it is to be picked into a shed and held by elements 3a-c against element 2 when picking is completed. In a modification, Fig. 5 (not shown) element (3') is stationary but adjustable and element (2') is carried on pivoted levers controlled by a spring on electromagnet. In a modification, overlay 11 e.g. of unhardened steel, light metal, titanium or plastics is loose and has a lining of hard chromium or the like or of cemented metal carbide or aluminium oxide.