GB1411299A - Anti-rotation washers for flanged or round headed screwed fastenings - Google Patents

Abstract

1411299 Locking nuts and bolts ROLLS-ROYCE (1971) Ltd 3 April 1974 [10 April 1973] 17067/73 Heading F2H A locking washer 20 has a peripheral flange 22 with at least one internally convexly curved portion 23 to resiliently engage at least frictionally the periphery of a flange or a round head of a bolt 18, setscrew, or nut used to fasten together two or more components such as 10, and at least one side to be located adjacent an abutment surface 14 of one of the components 10 to prevent rotation of the washer relative to the component. The washer may be generally square, Fig. 1, triangular (Fig. 3, not shown), elliptical (Fig. 4, not shown), or as shown in Fig. 5 with a single outwardly concave flange portion 23c. Each outwardly concave portion 23 may have an inner pip 26 to engage in one or more grooves in the head or flange of the bolt, setscrew, or nut, and/or an outwardly bent lip 25 to provide a lead-in to facilitate insertion of the head or flange into the washer. Slots 24 at the bases of the outwardly concave flange portions 23 allow resilient deflection of the portions. Where an abutment surface cannot be provided on one of the main components, a rectangular auxiliary washer (36) with at least one transverse rib (38, 40) to provide the abutment surface is non-rotatably held in a shallow groove (30) milled in one component (34), (Fig. 6, not shown). Alternatively, a channel shaped washer 42, Fig. 7, with holes 44, 46 to correspond to two fastener-receiving bores in a component is used to non-rotatably house at least one locking washer 20 which is axially located in the channel by dimples 54, 56. Cutouts 58, 60 in the lips 48, 50 of the channel flanges allow the locking washers to be extracted from the channel.