Sleeve for cardan joint or the like

摘要

This sleeve for a cardan joint or the like is moulded by blowing a polyester such as polyethylene terephthalate, which has the effect of imposing a biaxial orientation on the polyester at the same time as shaping it into a bellows or a sleeve 11. The polyester is firstly extruded, injection-moulded so as to form a blank which will have the desired thickness after blowing and the blank is then blown in a mould at the blow-moulding temperature of the polyester. An in-line blow-moulding process in a single phase may be applied, or a two-phase blow-moulding process with reheating. This latter process gives greater ease for maintaining the desired thickness in the undulations of the bellows and in the regions of the collars. <IMAGE>