WE CLAIM:
1. A method for producing a resin-impregnated fiber bundle roll body, comprising:
an unwinding step to take off a fiber bundle from a bobbin;
a winding step to roll up the fiber bundle on a winding core rotating around a fixed axis through a movable winding head to prepare a product; and
a leading step to lead the fiber bundle taken off in the unwinding step to the winding step between the unwinding step and the winding step, wherein
the leading step or the winding step includes a resin adhesion operation to impregnate the fiber bundle with a resin, and
the winding step includes a fiber content calculation operation to calculate a fiber content Vf [%] in a layer of the resin-impregnated fiber bundle being rolled up on the winding core of an intermediate product to control any one of (i) to (iv) according to the fiber content Vf [%]:
(i) a resin adhesion amount in the resin adhesion operation;
(ii) a winding tension of the fiber bundle applied to the intermediate product;
(iii) a removal amount of a surplus resin layer generated on an outer surface of the intermediate product; and
(iv) a resin viscosity in the intermediate product.
2. The method for producing a resin-impregnated fiber bundle roll body according
to claim 1, wherein the winding step further includes a resin-impregnated fiber bundle
layer thickness calculation operation to calculate a thickness tFRP of the layer of the resin-
impregnated fiber bundle and then the fiber content calculation operation is performed
by using the thickness tFRp.
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3. The method for producing a resin-impregnated fiber bundle roll body according
to claim 2, wherein
the winding step further includes an outer diameter measurement operation to measure an outer diameter of the winding core or the intermediate product, and
the thickness tFRP of the layer of the resin-impregnated fiber bundle, formed between a first time ti and a second time t2 later than first time ti, is calculated by using: a first outer diameter di of the winding core or the intermediate product at the first time ti; and a second outer diameter d.2 of the winding core or the intermediate product at the second time t2, the first and second outer diameters di and di being measured by the outer diameter measurement operation.
4. The method for producing a resin-impregnated fiber bundle roll body according
to claim 3, wherein
the winding step further includes a surplus resin layer thickness measurement operation to measure a thickness tr of the surplus resin layer generated on the outer surface of the intermediate product, and
the thickness tFRP of the layer of the resin-impregnated fiber bundle formed between the first time ti and the second time t2 is calculated by using: the first outer diameter di; the second outer diameter d2; and the thickness tr of the surplus resin layer measured by the surplus resin layer thickness measurement operation at the second time t2.
5. The method for producing a resin-impregnated fiber bundle roll body according
to claim 4, wherein the surplus resin layer thickness measurement operation is performed
by a photoelectric means or an ultrasonic wave means.
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6. The method for producing a resin-impregnated fiber bundle roll body according to any one of claims 3 to 5, wherein the outer diameter measurement operation is performed by a photoelectric means.
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