| 摘要 |
PURPOSE:To efficiently manufacture the bent hoses without employing mandrel by a method wherein tubular body in continuous form having fiber reinforcing layer, rubber external layer and thermoplastic resin layer covering in order name the outer periphery of rubber internal layer, the interior of which is filled with pressurized air, is subjected to bending operation and cut in pieces so as to install the resultant bent cut pieces in a form in order to be vulcanized and, after being removed from the form, frozen in order to separate the resin layer. CONSTITUTION:Under the condition that uncured rubber internal layer is extruded and, at the same time, pressurized air is filled in the interior of the rubber internal layer, fiber reinforcing layer is formed on the outer periphery of the rubber internal layer. Uncured rubber is extruded on the outer periphery of the reinforcing layer. Thermoplastic resin covers the outer periphery of the rubber external layer. Tubular body 11 in continuous form, the outer periphery of the resultant rubber external layer of which is covered by the thermoplastic resin layer and which has no mandrel therein, is cut off successively in pieces from end after being subjected to bending operation or cut off successively in pieces before being subjected to bending operation. Bent cut pieces obtained as mentioned above are installed in a form so as to be vulcanized and, after being removed from the form, frozen in order to separate the resin layer. The pressurized air encapsulated in the rubber internal layer is kept on being encapsulated until the covering of the outer periphery of the rubber external layer with the resin layer comes to an end. As the resin applied to the outer periphery of the rubber external layer, thermoplastic resin, which does not flow at vulcanizing temperature, such as 4-methylpentene-1 resin or the like is used. |
