JPH01112047A - Fly wheel and manufacture thereof - Google Patents

Abstract

PURPOSE:To produce an effect equivalent to that of a false equal energy variable pressure disc even by an equal thickness disc, by a method wherein a fly wheel is formed by fiber-reinforced plastic in which reinforcing fibers are aligned in the circumferential direction of a disc, and oxynitride glass fiber having a modulus of elasticity changed in the direction of length is wound as the reinforcing fiber. CONSTITUTION:In FRP in which reinforcing fibers are aligned in the circumferential direction of a disc, by using oxynitride glass fibers having a modulus of elasticity continuously decreased or increased in the direction of the length of a fiber, dynamic characteristics are changed in the radial direction of the disc. When the oxynitride glass fibers are applied for a fly wheel, by arranging reinforcing fibers, e.g. oxynitride glass, having a high nitrogen content, i.e. a high modulus of elasticity, on the inner side in a radial direction of the disc, even an equal thickness disc has the same effect as that of a false equal stress variable pressure disc, and besides the weight of the disc can be decreased. By arranging reinforcing fibers, having a high nitrogen content and a high modulus of elasticity, toward the outside in a radial direction, a substance in which a circumferential stress and a radial stress are distributed in a proper state is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to flywheels used for energy storage.

Conventional energy storage flywheels are required to have a high energy density per weight, and such flywheels include disks made of filament winding of fiber reinforced plastic (FRP).

Problem 1 to be solved by the invention: However, in conventional flywheels of this type, the entire disc is made of homogeneous PRP, and the strength in the radial direction is significantly lower than the strength in the circumferential direction of the disc. It has the disadvantage of being low.

As a solution to this drawback, a method using two types of reinforcing fibers (for example, glass fiber and carbon fiber) with different elastic moduli has been proposed. That is, it has been proposed that the blending ratio of fibers with different elastic moduli is changed from the inside to the outside in the radial direction of the disk (Japanese Patent Laid-Open No. 54-6526).
No. 6).

However, it is technically difficult to continuously change the blending ratio of the two types of fibers, and the change can only be made in stages. Further, such a flywheel cannot be created using continuous fibers, and it is necessary to use short fibers as reinforcing fibers.

The present invention provides a flywheel that has the same effect as a quasi-isostress variable disk even with a disk of equal thickness, a flywheel that has an appropriate distribution of stress in the circumferential direction and stress in the radial direction, and a flywheel that can be manufactured easily. The purpose is to provide a method for

In order to solve the four problems, the present invention consists of a fiber-reinforced plastic in which reinforcing fibers are arranged in the circumferential direction of a disk, and the reinforcing fibers are oxynitride glass fibers whose elastic modulus changes in the longitudinal direction. The present invention provides a flywheel characterized by being wound, and a method for manufacturing the same.

The flywheel of the present invention uses oxynitride glass fibers whose elastic modulus continuously decreases or increases in the length direction of the fibers in F'RP in which reinforcing fibers are arranged in the circumferential direction of the disk. By using this, the mechanical properties change in the radial direction of the disk. This makes it possible to obtain a flywheel that has excellent characteristics, or is optimal in terms of rotational strength and cost.

In the flywheel of the present invention, reinforcing fibers of oxynitride glass with a high nitrogen content, that is, a high modulus of elasticity, are arranged on the inside of the disk in the radial direction, so that even if the disk is of equal thickness, it can be made into a quasi-equal stress transformation circle. It has the same effect as a disk, but can also be made lighter. Further, by arranging reinforcing fibers having a high nitrogen content and a large elastic modulus toward the outside in the radial direction, it is possible to obtain a flywheel in which circumferential stress and radial stress are appropriately distributed.

Oxynitride glass, which is the raw material for glass fiber used in the present invention, has a structure in which the oxygen atoms of oxide glass are replaced with nitrogen, and the bond valence of the nitrogen atom is 3.
Because of this, it has a higher modulus of elasticity than conventional glass. Methods for producing such oxina-itride glasses include a sol-gel method in which metal alkoxides are hydrolyzed and then dehydrated and condensed, a melting method in which metal oxides and metal nitrides are melted, N, gas blowing method, porous The elastic modulus of 12.500 kg/mm', which could not be achieved with conventional glass fibers, has been achieved using NH and gas treatment methods for glass fibers.
It is possible to obtain more than that.

The oxynitride glass fibers used as reinforcing fibers in the present invention contain 13 to 24 at% of Si and 10 to 20% of Ca.
21 at%, MgO~5.2 at%, AlO~15.
1at%, NO, 5-25at%, MO-5at%
% (M: Z r SS rN Ba, Y
SCes Na%B - L a 1K 5Ti) is preferred.

If the Si content is less than the above range, crystallization will occur and a glass state will not be obtained. Moreover, when the amount exceeds this range, the elastic modulus decreases to 12,500 kg/mm'' or less.

Moreover, if the Ca content is less than the above range, crystallization will occur, while if it exceeds this range, the elastic modulus will be 12,500 k
g/IIIm”.

Furthermore, if the Mg content exceeds the above range, crystals will occur.

Furthermore, by increasing or decreasing the nitrogen content within the above range, the elastic modulus of the reinforcing fibers can be appropriately changed. Also,
If the nitrogen content exceeds the above range, crystallization will occur.

The oxynitride glass used in the present invention has strength,
It is manufactured by a melting method in terms of N and content m. To obtain oxynitride glass by the melting method, metal nitride is added to metal oxide and melted at high temperature.

Examples of metal oxides include 5ift, CaO1MgO
SA L toa, SrO%Ha, OlK, 01Lat
()s, Y, 0. , Z r Ot, Tilt, NatO
Examples include lK, o, BaO1B, 03, and the like.

Furthermore, examples of metal nitrides include Si3N+ and AIN.

To melt the mixture of these metal oxides and metal nitrides, a heating furnace such as an electric furnace or an image furnace is used in a nitrogen atmosphere at a temperature of 1400-1900°C and a heating rate of IO to 800°C.
Process at °C/min.

The obtained glass was heated under a nitrogen atmosphere at a temperature of 1100 to 160°C.
Heating and melting at 0°C, spinning speed 20-3000 m/
A continuous fiber is obtained by spinning with a win.

The obtained glass fiber has an elastic modulus of 12,500 to 1,800.
0kg/mm! , tensile strength 70-500 kg/m
m” is obtained.

The fiber diameter of the glass fiber is preferably 3 to 150 μm. If the fiber diameter is smaller than this, spinning is difficult;
On the other hand, if it exceeds this range, the strength will be extremely reduced, which is not preferable.

In addition, as thermosetting resins, unsaturated polyester resins,
Examples include phenol resins and epoxy resins, and these may be used alone or in combination of two or more. Further, the mixing ratio of glass fiber in the prepreg is about 40 to 60% by weight.

To manufacture the flywheel of the present invention, first, fibers whose nitrogen content is continuously varied are manufactured.

That is, s S i Ot , Ca COs , M g
01A 1.03 and other raw materials are mixed, fired in air, and then pulverized. This is put into the raw material feeder 1 shown in FIG. 1, and mixed by the continuous mixer 3 while increasing the amount of nitride powder such as 5taN4 powder fed into the other raw material feeder 2, and then transferred to the spinning furnace 4. supply to The powder melted in the spinning furnace 4 is drawn out from the bottom as fibers and treated with a surface treatment roller 6, then formed into a single strand by a focusing pad 7, and wound up by a winder 8. Next, the rolled bundle is aligned in one direction and impregnated with resin to produce a prepreg. The nitrogen content of the glass fibers in the prepreg increases continuously in one direction. moreover,
This tape is wound around the rotating shaft starting from the side with the lowest nitrogen content and molded.

In this way, a flywheel is obtained whose elastic modulus increases continuously from the center outward.

Therefore, if the outer diameter of the flywheel is R, the nitrogen content and circumferential elastic modulus at the position R- in the radial direction from the center increase linearly, and the radial stress is lower than when the N content is constant. Suitable for closed wheel discs. It is also superior to conventional glass fiber and carbon fiber hybrid flywheels, and the manufacturing process is simpler.

Further, in the present invention, the flywheel may be wound around the shaft starting from a portion with a high nitrogen content, and the strength decreases as the nitrogen content decreases toward the outside.

Kannomasu Next, the present invention will be explained in more detail with reference to Examples.

Example I SiOx 22.8mol%, CaCO540.8m
o1%, MgO12,0mo1%, A 1 gos 1
4.4 mo1% was mixed, baked in air at 1500°C for 2 hours, and then pulverized (particle size 1 to 10 μi). This is put into the raw material feeder 1 shown in Fig. 1 and mixed with the 5tsN+ powder contained in the other raw material feeder 2 while increasing the amount of 5tsN+ powder with a nitrogen content of 1 to 12% by weight linearly. Mixing was performed using a mechanical mixer 3 and the mixture was supplied to a spinning furnace 4.

The powder melted in the spinning furnace 4 is pulled out from the lower bushing set at 1380°C and passed through the surface treatment roller 6.
After processing, it is made into one strand with a focusing vat 7,
It was wound up using winder 8.

Next, this rolled bundle is aligned in one direction and impregnated with resin to create a prepreg. In the prepreg, the glass fibers have a continuously increasing nitrogen content from one side to the other. This tape was wound around a rotating shaft starting from the side with the lowest nitrogen content and molded. Therefore, a flywheel was obtained in which the elastic modulus increases continuously from the center to the outside.

Effects of the Invention According to the present invention, by arranging reinforcing fibers with a high nitrogen content and a large elastic modulus on the inside in the radial direction, it is possible to easily achieve the same effect as a quasi-equal stress transformation disk even with a disk of equal thickness. A lightweight flywheel can be obtained. Further, by arranging reinforcing fibers having a large elastic modulus toward the outside in the radial direction, it is possible to obtain a flywheel in which circumferential stress and radial stress are appropriately distributed.

[Brief explanation of the drawing]

FIG. 1 is a schematic diagram showing an apparatus for producing oxynitride glass fibers used as reinforcing fibers for flywheels of the present invention. The main symbols in the figure are as follows. 1: Raw material charging machine, 2: Nitride charging machine, 4: Spinning furnace.

Claims (2)

[Claims] (1) A fly made of fiber-reinforced plastic with reinforcing fibers arranged in the circumferential direction of a disk, and characterized in that the reinforcing fibers are wound with oxynitride glass fibers whose elastic modulus changes in the length direction. Wheel. (2) A fly characterized by spinning continuous fibers of oxynitride glass while continuously changing the nitrogen content, forming prepreg using the fibers, and winding the prepreg into a disk shape. Wheel manufacturing method.