摘要 |
A water hose includes a heclically shaped coiled tube having interior and exterior elliptical cross-sections with a flexural modulus greater than the flexural modulus of a coiled tube having interior and exterior circular cross-sections and the same neutral center line length as the elliptical cross-sections, but otherwise having the same properties as the elliptical cross-sections. The tube is made of extruded plastic resin having a durometer hardness measurement approximately in the range of 70-80 Shore A and has on its periphery ridges extending longitudinally at right angles to the elliptical cross-sections. In first and second embodiments, the elliptical cross-sections have major and minor axes respectively extending in the direction of the coil longitudinal axis and in planes extending at right angles to the longitudinal axis, and vice versa.
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