Lightweight strut for framework or machine - has inner and outer tubes with glass fibre reinforced layers between end caps

摘要

The hollow tube which may form part of a framework or machine, consists of an inner tube (10) and an outer tube (12) gripped between end caps. Each end cap has a rounded flanged body (21) which fits inside the two tubes, and their outer ends are clamped by an outer sleeve. This screws onto the externally threaded neck of the end cap. An eye bolt can then be screwed into the necked part of the end cap and locked by a nut. The inner tube (10) is made from plastics reinforced by fibres, and consists of an outer layer of fibres wound over longitudinal unidirectional fibres, to withstand tensile forces. The outer tube consists of an inner layer (25) of longitudinal fibres, and an outer layer (26) wound onto it. The longitudinal fibres are wound round a peg (22) which is embedded into the rounded shoulder (17) of the end cap.