Dynamic Garden Hoses -1 (Magic Hose)

The word of "Dynamic Hoses" or "Dynamic Garden Hoses" are seldom heard but the new type of hoses named like X-Hose, Pocket Hose, Magic Hose, which expand (or more remarkably "extend and stretch") and contract (or retract) by the presence and absence of water pressure can be call "Dynamic Hoses" in contrast to the conventional hoses which do not change their shapes dramatically so they are rather static to our naked eyes. Some flat hoses change their shapes from flat to round by application of water pressure but not so dynamic as expandable and contractible hoses.

The trick of a expandable and contractible hose can be found in the patent documents of X-Hose.

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In the expanded or extended condition, illustrated in Figs. 4, 6 and 9, the inner tube member 14 is expanded or stretched. In this expanded condition the non-elastic outer tube member 12 constrains the lateral expansion of inner tube member 14. The outer tube member 12 is also taut, smooth, and relatively flat along its length in this extended condition. Since the outer tube member 12 will not expand laterally or longitudinally, the actual length and width of the outer tube member 12 determines the maximum length and maximum width of the hose 10 in its expanded condition. Thus the diameter and length of the outer tube member 12 determines the diameter and length of the water hose of the present invention upon the application of water pressure to the interior of the elastic inner tube member 14. This diameter and length of the non-elastic outer tube member 12 is the final diameter and the final length of the hose 10 when it is in its expanded condition and in use to transport or deliver water.

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<the outer tube member 12 will not expand laterally or longitudinally> is misleading as the outer tube is woven fabric but has wrinkles or is folded so it expands longitudinally until the wrinkled parts are unwrinkled, either partially or fully, when the inner tube expands longitudinally or simply extends.

The above is the basic description of the dynamism of X-Hose - a expandable and contractible hose.
The inner rubber tube changes its shape by water pressure and the outer fabric tube also changes its shape by the movement, mostly lateral and longitudinal unfolding. This is very dynamic when you see it. The movement is like that of a snake but very erratic or somehow funny as we know it is not a real snake. The condition of a hose changes continuously after application of water pressure and changes in a very complicated manner as the condition changes unexpectedly and erratically. At least the non-elastic outer fabric tube constrains the lateral (and also longitudinal) expansion of the elastic inner tube but constrains unexpectedly and erratically. The wrinkled outer tube is unwrinkled automatically by the water pressure but not fully unless you help it by hands, which suggests that the outer fabric tube may restrict the axial (longitudinal) expansion of the inner tube due to some reactive force of the outer wrinkled fabric tube and some friction between the surfaces of the inner and outer tubes.

The common rubber hoses are thick enough to prevent to be easily broken or burst and do not change the shape noticeably, especially longitudinal or axial direction. If not thick enough the hose tends to expand radially or bulge when pressurized due to the physics (or mechanics) law.

The hose mechanism is not simple at all and rather complicated but very interesting to study. This article will continue to expand our idea and concept of Dynamic Hoses - or we call it Garden Hose Dynamics or more generally Hose Dynamics.


Asnet Dynamic Hoses - a division of 
Asnet Components Ltd
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