Patent ID: 7204286
Filing Date: 2007-04-17
Classification: B29C,B29L

Abstract:
1. An apparatus for continuously forming a fiber reinforced plastic square pipe by molding a semi-cured prepreg material formed by impregnating a thermosetting resin in carbon fiber or glass fiber, the apparatus comprising: a square rod-shaped core having an outer diameter that is smaller than an inner diameter of the square pipe to be formed and a tapered portion with a diameter size that becomes equal to the inner diameter of the molded product before a hot press, the core supported and fixed at one end thereof; a device for placing a release film on the surface of the core; a device for laminating a predetermined number of prepreg sheets sequentially on the release film; a device for wrapping a tape-like release film in a circumferential direction after the predetermined number of prepreg sheets are laminated; a device for placing the release film on an outer layer of a laminated prepreg sheets; a device for hot pressing for providing heat and pressure to the prepreg sheets; a heating furnace for providing additional heating to a hot-pressed prepreg sheets; a device for discontinuously pulling a formed prepreg square pipe; and a device for holding a square pipe at hot press; wherein the device for wrapping the tape-like release film comprises: a ring-like guide rail disposed on a base; a rotary ring disposed on a ring-like inner circumference of the guide rail in such a manner that the ring is capable of moving in circling motion; a driving device of the rotary ring; a block mounted on the rotary ring; and a reel fixed to the block for feeding the tape-like release film; which reel controls tension placed on the tape-like release film being fed; wherein the tape-like release film includes a stretch film having resistance to heat equal to or higher than a curing temperature of the prepreg being used and generates thermal contraction stress.