| 摘要 |
<p>HOT MELT MULTI-SECTION HOSE HEATING SYSTEM A heating system is disclosed for a hot melt hose having multiple physically and thermally interchangeable series-connected heated hose sections wherein different hose sections exhibit different electrical power requirements per unit length. The multiple sections of the hose are physically and electrically interconnected end-to-end between a pressurized hot melt source and a hot melt dispenser, such as a hand-held gun, having a triggercontrolled valve for regulating the flow of hot melt from the gun. Each of the hose sections includes an inner, fluid impervious, chemically inert tube, preferably fabricated of tetrafluoroethylene; an electrically conductive multi-strand braided sheath snugly embracing the exterior surface of the inner tube and in intimate heat transfer contact therewith for supplying strength and heat to the tube; and an outer sheath of thermal insulating material surrounding the intermediate braided sheath for minimizing heat loss to the environment. At least two of the hose sections have outer thermal insulating layers exhibiting different heat loss per unit length and associated electrically conductive braided sheaths of substantially equal strength and flexibility, but exhibiting different electrical power consumption per unit length. As such, when the braided sheaths of different hose construction are series-connected and a constant current from a regulated constant current power source is passed through the serially-connected braided sheaths, the temperature of the hot melt material within the different hose sections is maintained at substantially the same temperature notwithstanding the difference in the heat loss characteristics of the thermal insulating outer layers of the different hoses.</p> |
