Abstract: A fastener system capable of clamping a workpiece that provides for enhanced distribution of the internal forces that are generated in the components as a result of the assembly of the system. The fastener system includes an externally threaded member having a thread formed thereon with a substantially non-triangular profile, and an internally threaded member having a thread formed therein which also includes a substantially non-triangular profile. In assembled form, the substantially non-triangular thread faces of the internally and externally threaded members mate along a contact face and, by virtue of their unique thread forms, are able to withstand axial loads of greater magnitude than comparable systems employing threads having substantially triangular profiles.

Abstract: A threaded fastener is presented of the thread-forming type, wherein there is defined, during driving thereof relative to a workpiece a combination of force couples and a resultant moment of force couples to develop material flow of the workpiece material about the threads to give face contact between the mating threads of the fastener and threads formed in the workpiece thereby for improved loading.

Abstract: A detection device comprising a longitudinally extending hollow body (7) having a light input position (11) located transversely between the ends thereof, one end comprising an output or viewing window end (10) and the other end comprising an output/input window end (b 12). Light transmissive fibres are provided to connect between the light input position (11) and the output/input window end (12) and between such output/input window end (12) and the viewing window end (10). Means (17, 18) are provided to facilitate varying the angle of incidence of light rays impinging on the fibres (21) located at the light input position (11) so as to facilitate focusing the length of focus of light rays emitted from the fibres (22) at the output portion at the output/input window end (12) to be reflected back to the fibres (23) of the input portion at the output/input window end (12).