ARTEFACTS INCORPORATING LOAD LIMITING MEANS

摘要

1515844 Bolting; load limiting devices NATIONAL RESEARCH DEVELOPMENT CORP 2 June 1975 [3 June 1974] 24507/74 Headings F2S and F2H [Also in Division F1] The Specification discloses a number of embodiments of an artefact including screwthreaded means and used as a clamping device which incorporates load limiting means. In the embodiment of Fig. 1, a block 5 is a sliding fit in a cavity 4 in a rectangular nut member 3 and has a screw-threaded recess 8 with which a bolt 9 engages. The block 5 serves to anchor an assembly of crimped wires 1 which extend through another cavity in the nut member 3 between spacer elements 2. The bolt 9 passes through holes in plate members 10, 11 and when it is screwed into the recess 8 the member 3 is moved with the block 5. Turning of bolt 9 brings plate members 10, 11 together and wires 1 are eventually caused to be deformed and block 5 is drawn along the cavity. Such a clamping device may be used to clamp a pressure release cap on a pressure vessel. In the embodiment of Fig. 2 (not shown) crimped wires (21) pass through tubes (22) and are anchored in a block (24) passing through holes in plate members 10, 11 and having a screw-thread extension (24a) engaged by a nut member (25). A washer member (26) may be provided between nut member (25) and plate member (10). In the embodiment of Fig. 3 (not shown) the crimped wires (31) which pass through tubes (36) are anchored in a cylindrical block (32) which is of larger diameter than the hole in plate member 10. A retaining tube (33) for tubes (36) is threaded to be engaged by a nut member (34). In the alternative embodiment of Fig. 4, a stud member 40 is screwed into a plate member 41 and extends through a plate member 42 which it is desired to clamp to member 41. The stud member 40 comprises a core 43 anchored at the bottom and a tubular extension 45 with a screw-threaded upper end portion 44 engaged by a nut member 46. As the nut member 46 is tightened dupile deformation will commence at the lower end 45 of the extension. In the embodiment of Fig. 5 (not shown) a bolt (50) passing through plate members (51, 52) engages a screw-threaded portion (53) in a core tube (54), a deforming tubular member (55) being secured to the lower end portion of the core tube (54). The end of the tubular member (55) is secured to the end of a reaction tube (57) which acts as a nut member to engage the plate member (51).