Method and apparatus for continuously draw-molding fiber reinforced plastic rod formed with spiral groove

An apparatus for continuously draw-molding a fiber reinforced plastic rod formed with a spiral groove comprising:

• a fiber supplying device for supplying a fiber bundle which is composed of a plurality of fibers under predetermined tension being applied, said fiber supplying device including a roving rack for drawing a number of reinforcing fibers while applying tension thereto, said tension being applied by a torque limiter mounted to rotation support portions of bobbins around which reinforcing fibers are wound and the bobbins are rotated against rotation resistance of the torque limiters, and a resin bath unit having a resin bath containing thermosetting resin in a molten state;
• a resin impregnating device for impregnating an unhardened thermosetting resin in the fiber bundle supplied from the fiber supplying device;
• a tape wind-up device for applying a tension to a tape and winding the tape around the fiber bundle at a constant tape wind-up angle on the fiber bundle with a predetermined pitch;
• a heating mold having a cross-sectional shape substantially equal to that of a rod to be molded, in which the thermosetting resin is hardened during the passing of the fiber bundle in the heating mold;
• a tape take-up device, including a control mechanism for controlling a tape take-up position to be substantially constant, for taking up the tape, from the fiber bundle discharged from the heating mold;
• and
• a rod drawing device for drawing out the rod molded in the heating mold therefrom at inlet side.