Reinforced tubes

A reinforced medico-surgical tube including a shaft of a flexible plastics material reinforced along a major part of its length by a reinforcement in the form of a coil of a filament of stiff material embedded within the plastics, characterised in that the coil has multiple turns formed by loops of the filament, that the loops have opposite closed ends extending around the shaft in opposite directions towards one another and towards a longitudinal locus between the closed ends of the loops, and that the longitudinal locus along a first region of the tube defines a path wider than that along a second region along the tube.

A method of making a reinforced medico-surgical tube, characterised in that the method includes the steps of:

• forming a flat coil of a stiff material having multiple loops arranged side by side along the length of the coil, the coil including at least a first region and a second region where the width of the coil is different along the two regions;
• bending the coil along its longitudinal axis into a tubular form such as to form a longitudinal gap between the ends of the loops along at least the first region;
• and subsequently forming a shaft by embedding the coil within a flexible plastics material.

A coil for use in reinforcing a medico-surgical tube, characterised in that the coil has multiple turns formed by loops of a filament of a stiff material, that the loops have opposite closed ends, that loops along a first region of the coil are shorter than loops along a second region, such that when the coil is bent into a tubular form along its longitudinal axis to bring the closed ends of the loops of the second region close to one another the closed ends of the loops of the first region are spaced from one another by a gap along the length of the first region.