GB1294419A - Fastener - Google Patents

Abstract

1294419 Riveting VSI CORP 10 Aug 1971 [10 Aug 1970] 37559/71 Heading B3U [Also in Division F2] A fastener comprises a first member 11 (Figs. 1A, 1C) having a head 13 and a sleeve 15 extending therefrom, with a shank 17, having an annular groove 29, extending from the head 13 through and beyond the sleeve 15, and a second member 31 having a head 33 and a deformable sleeve 37 extending therefrom, the second member 31 being placed on the shank 17 so that the sleeves 15, 37 extend towards each other. When the sleeves are forced together with the fastener in a hole in a workpiece, part of the sleeve 37 of the second member 31 is deformed radially inwardly by the sleeve 15 of the first member to engage in the groove 29 of the shank 17 to lock the two members together. In Figs. 1A, 1C, the shank 17 is part of a bolt the head 19 of which is rotatably retained in the head 13 of the first member 11. On installation the second member 31 is held against rotation by a tool (not shown) and the bolt is rotated by its shank end 25 to draw the members 11, 31 towards each other. The chamfered leading end 41 of second member 31 is forced into the sleeve 15 of the first member so that the end 41 is deformed into the groove 29 of the shank and the leading end of the sleeve 15 is deformed radially outwardly to engage the wall of the hole. At a predetermined torque, the end 25 of the shank breaks off flush with the second member head 33 to prevent excessive clamping action. In a modification (Figs. 2A-2C, not shown) the sleeve of the first member is thick enough to resist outward deformation, and is of the same outside diameter as the base portion of the second member sleeve. In Fig. 3 (not shown), the sleeve of the first member is a separate member force-fitted on to the shank of a bolt, the bolt head forming the complete head of the first member. In Fig. 4, a sleeve 103 is secured over the shank of a threadless bolt 101. The second member 107 is forced into the hole while pulling the bolt 101 by its tip, so that the leading portion of the second member sleeve 111 is deformed into the annular groove 105 of the bolt by the sleeve 103. The bolt tip snaps off at 113 after installation. Fig. 5 shows a blind fastener in which the end of a sleeve 125 is deformed outwardly at 135 after insertion of the fastener through a hole, to form the head of the first member. The sleeve 125 is initially in one piece, waisted at 131, to form the sleeves of both members. After the end portion 135 has been deformed, pressure on the head 129 of the sleeve fractures the sleeve at 131, the upper portion being forced into the annular groove 137 of the bolt by the lower half.