JP5765959B2 - FRP structure - Google Patents

Description

  The present invention relates to an FRP structure used for boats, tanks, large-area panels, and the like, and more particularly to a connecting portion of a reinforcing cloth used for the FRP structure when molding such a large structural material.

Conventionally, when trying to produce a panel (FRP panel) made of lightweight fiber reinforced plastic (hereinafter referred to as FRP), it is necessary to use a high-strength fiber reinforced fabric. As the fiber reinforced fabric, a roving cloth woven from a fabric of a 0 ° direction layer in the length direction and a 90 ° direction layer (0 ° / 90 °) in the width direction is used, but the fiber extends along the length direction. Swell up and down. For this reason, unevenness is generated on the surface, so that it is not suitable for a structural material for which smoothing of the surface is desired.
On the other hand, for example, the multi-axis overlap stitch cloth disclosed in Patent Document 1 and the like is obtained by stitching and unifying fibers stacked in the same direction in parallel, eliminating the undulation of the fibers. It is also called non-crimp cross.
Such a non-crimp cloth is a high-performance fiber-reinforced cloth with high strength and Young's modulus against in-plane tensile load and compressive load because each fiber is linear compared to roving cloth. .

JP 2003-94449 A

By the way, when a molding object is large, for example, when molding a large FRP panel, if it is intended to use a 0 ° / 90 ° cross, it is necessary to arrange a cross with a finite width so as to cover the whole. At that time, it is necessary to overlap the width portion of the cloth more than a predetermined length (hereinafter simply referred to as “wrap”). This is for wrapping the cross in the 90 ° direction to continue the strength and rigidity in the direction (width direction).
However, when a tensile load is generated in the formed surface, the 0 ° direction is continuous fiber and there is no break, so the reliability is high. However, since the 90 ° direction has a wrap part, the tensile force of the fiber is the resin of the wrap part. This is transmitted to the other via the shearing force, and there is a possibility of shear fracture of the lap portion.
For this reason, it is necessary to appropriately set the basis weight in consideration of the basis weight of the continuous fibers (fiber weight per unit area) and the strength of the resin.
In general, reinforcement is also required in the ± 45 ° direction. In this case, a polyaxial stitch fabric of ± 45 ° may be used, but the load generated in the ± 45 ° direction is the main in the 0 ° / 90 ° direction. Since it is often lower than the strength direction, it is not often a problem as the strength is reduced at the overlapping portion in the 90 ° direction.
Moreover, when a fiber reinforced cloth is connected by overlap, the unevenness | corrugation of a wrap part will become large and the smoothness of the surface will also be impaired.

  An object of this invention is to provide the FRP structure which can improve in-plane intensity | strength and was excellent in surface smoothness in view of said subject.

The FRP structure according to the present invention is an FRP structure formed by connecting fiber reinforced fabrics in the width direction, and the fiber reinforced fabrics having a 0 ° direction layer and a 90 ° direction layer are butted in the width direction. The unidirectional band fabric of the 90 ° direction layer is directly laminated and integrally formed on the 90 ° direction layer of each fiber reinforced fabric at the butt portion.
Moreover, it is preferable to use a stitch cloth as a fiber reinforced cloth.

  In addition, the FRP structure according to the present invention is formed by abutment of stitch fiber reinforced fabrics of ± 45 ° direction layers, and a unidirectional band fabric of 90 ° directions layered directly on the abutting portion. is there.

  The “FRP structure” referred to in the present invention is not limited to a molded product obtained by laminating only fiber reinforced fabrics including a unidirectional band fabric of 90 ° direction layers, but also plastics, metals, ceramics, fabrics, woods, and the like. It includes a composite molded product obtained by laminating types or a plurality of types and the fiber reinforced fabric.

  In the FRP structure of the present invention, fiber reinforced fabrics having a 0 ° direction layer and a 90 ° direction layer are abutted, and a one-way band fabric of a 90 ° layer is directly formed on the 90 ° direction layer of the abutting portion. Since they are formed integrally with each other, there is no interposition of a 0 ° direction layer that is easily sheared and broken as in the prior art, so that the in-plane strength is improved and the surface smoothness is improved.

It is a schematic diagram which shows the structure of the FRP structure which concerns on Embodiment 1 of this invention, and is a figure which shows the change from a prior art example. It is the top view (a) and side view (b) of the FRP structure shown in FIG. It is a figure which shows the definition of the 0 degree direction layer and 90 degree direction layer of a fiber reinforced fabric. It is a schematic diagram which shows the structure of the FRP structure which concerns on Embodiment 2 of this invention.

  Hereinafter, embodiments of the FRP structure according to the present invention will be described with reference to the drawings.

Embodiment 1 FIG.
FIG. 1 is a schematic diagram showing the configuration of the FRP structure according to Embodiment 1 of the present invention, and shows a change from the conventional example. 2 is a plan view (a) and a side view (b) of the FRP structure shown in FIG. 1, and FIG. 3 is a diagram showing the definition of the 0 ° direction layer and the 90 ° direction layer of the fiber reinforced fabric. is there.
In FIG. 1 to FIG. 3, reference numeral 1 denotes a fiber reinforced fabric composed of a 0 ° direction layer 11 and a 90 ° direction layer 12. In this example, a stitch fabric stitched with stitch yarns 13 is shown.

Conventionally, when the object to be molded is large, as shown in FIG. 1 (A), one fiber is formed between the fiber reinforced fabrics 1 and 1 composed of the same 0 ° direction layer 11 and 90 ° direction layer 12. The reinforcing cloth 1 was partially wrapped in the width direction to form a width direction wrap portion (0 ° / 90 ° cross wrap portion) 14.
However, in this structure, there are problems in the strength in the width direction and the smoothness of the surface as described above, so the present invention is configured as shown in FIG.
That is, the fiber reinforced fabrics 1 composed of the same 0 ° direction layer 11 and 90 ° direction layer 12 are butted together, and the one-way band fabric 2 of the 90 ° direction layer is directly placed on the 90 ° direction layer 12 of the butted portion. They are stacked and integrally molded.
The molding is performed by a VARTM (Vacuum Assisted Resin Transfer Molding) method generally used as a resin vacuum impregnation molding method.
1 and the like show a single-layer FRP molded product, the FRP structure of the present invention is formed by laminating a plurality of sets of fiber reinforced fabrics 1 and unidirectional band fabrics 2. At that time, the connecting portions 3 are alternately shifted and stacked so as not to line up in a row in the thickness direction.

According to the configuration of the present embodiment, the unidirectional band fabric 2 of the 90 ° direction layer is directly overlapped and connected to the 90 ° direction layer 12 of the fiber reinforced fabric 1, so that the 90 ° direction (width direction). There is an effect of improving the strength against.
In addition, since the thickness of the wrap portion can be halved compared to the method of overlapping the fiber reinforced fabric 1, the unevenness of the entire laminate is reduced, and as a result, an FRP structure having a smoother surface can be obtained. There is.

Embodiment 2. FIG.
4A and 4B are schematic views showing the configuration of the FRP structure according to Embodiment 2 of the present invention, in which FIG. 4A is a plan view and FIG. 4B is a side view.
In FIG. 4, 4 is a stitch fiber reinforced fabric of ± 45 ° direction layers. Reference numeral 2 denotes a unidirectional band fabric of a 90 ° direction layer.
As described above, it is generally considered that the main load often does not work in the direction of the ± 45 ° direction layer. In that case, as in the first embodiment, the stitch fiber reinforced fabrics 4 of the ± 45 ° direction layer are butted together, and the one-way band fabric 2 of the 90 ° layer is directly overlapped on the butted portion and integrally molded. Is.

  According to this configuration, when a large load is applied in the direction of ± 45 °, it is possible to ensure the connection strength that can withstand the load in the direction at the connection portion 3. Further, when a crack occurs in this joint, it occurs along the butt line of the cloth, so it is reasonable to reinforce it with a cloth of 90 ° direction layer that reinforces the direction perpendicular to the line.

  Although illustration is omitted, when the fiber reinforced cloth is connected also in the length method (0 ° direction), the fiber reinforced fabrics 1 are abutted with each other in the same way, and the 0 ° layer of the abutting portion is abutted. The unidirectional band fabric 2 of the 90 ° direction layer may be directly stacked on 11 and integrally molded.

DESCRIPTION OF SYMBOLS 1 Fiber reinforced cloth 2 Unidirectional band cloth of 90 degree direction layer 3 Connection part 4 Stitch fiber reinforced cloth of +/- 45 degree direction layer 110 0 direction layer 12 90 degree direction layer 13 Stitch yarn

Claims (3)

An FRP structure formed by connecting fiber reinforced fabrics in the width direction,
Fiber reinforced fabrics having a 0 ° direction layer and a 90 ° direction layer are butted in the width direction, and a 90 ° layer unidirectional band is formed on the 90 ° direction layer of each fiber reinforced fabric at the butted portion . An FRP structure characterized by being directly stacked and integrally formed.   The FRP structure according to claim 1, wherein a stitch cloth is used as the fiber reinforced cloth. An FRP structure formed by connecting fiber reinforced fabrics in the width direction,
An FRP structure characterized in that stitch fiber reinforced fabrics having a ± 45 ° direction layer are butted together, and a unidirectional band fabric of a 90 ° direction layer is directly laminated on the butted portion and integrally formed.

Images