JPH0680240B2 - Equipment for manufacturing oriented fiber aggregates - Google Patents

Description

TECHNICAL FIELD The present invention relates to an apparatus for producing an oriented fiber assembly, and more specifically to an apparatus for producing a fiber assembly in which many fibers are one-dimensionally oriented. This "one-dimensional orientation" means that, for example, most of the fibers
It means that they all face in almost the same direction. Note that this is used not only in the case of the fiber assembly but also in the orientation step and the like described below.

[Prior Art] Conventionally, it has been attempted to use the following device in order to obtain a fiber assembly made of relatively short fibers such as short fibers or whiskers.

One of them is the centrifugal molding device shown in FIG.
-65200 publication). In this centrifugal molding device, the outer cylinder 21
Fibers such as silicon carbide whiskers are supplied from the supply pipe 24 into the filtration membrane 25 in the porous cylindrical container 23 arranged inside, and the hollow aggregate 26 of the fibers can be formed by the centrifugal action. Incidentally, reference numeral 22 in the figure indicates a drainage port.

As another conventional device, there is a suction molding device shown in FIG. In this suction molding device, a predetermined fiber mixed liquid 34 is put in a cylinder 31, and the mixed liquid 34 is pressurized by using a pressure plunger 32 arranged on the upper portion of the cylinder 31, and the bottom portion of the cylinder 31 is By vacuum suctioning and removing the filtrate from the filter material 33 arranged in the above, the fibers can be oriented to form a fiber assembly.

However, in the fiber assembly formed by using the above centrifugal molding apparatus or suction molding apparatus, the fibers are not one-dimensionally oriented but two-dimensionally or three-dimensionally oriented. Therefore, in this fiber assembly, the strength when the fiber assembly is made of fiber reinforced metal (hereinafter referred to as FRM) is not sufficiently strengthened in a predetermined one-dimensional direction, the fiber volume ratio is low, and the compression molding There are drawbacks such as the large spring bag.

That is, in this conventional manufacturing apparatus, although there is a desire to obtain a fiber assembly in which the fibers are oriented in a predetermined one-dimensional direction, a fiber assembly in which the fibers are one-dimensionally oriented can be obtained. However, only a two-dimensionally or three-dimensionally oriented fiber assembly was obtained.

[Problems to be Solved by the Invention] The present invention overcomes the above-mentioned drawbacks and provides a high-strength FRM in a predetermined one-dimensional direction when used as an FRM, and has a high fiber volume ratio and a spring bag. An object of the present invention is to provide a manufacturing apparatus capable of manufacturing a small number of fiber aggregates in which fibers are one-dimensionally oriented.

[Means for Solving Problems] The present manufacturing apparatus includes an orientation tank, at least a pair of positive and negative electrodes, and a mouthpiece device described below.

As shown in the schematic diagram of FIG. 1, for example, the orientation tank is supplied with a dielectric liquid 2 in which fibers 1 such as short fibers are dispersed upward, and a supply unit 4 for supplying the dielectric liquid downward, and a downward direction. Further, it has a discharge part 6 for discharging the dielectric liquid 2 and an orientation part 5 for moving the dielectric liquid downward between the supply part 4 and the discharge part 6.

The supply unit may have positive and negative electrodes as shown in FIG. 1, or may have no positive and negative electrodes as shown in FIG.

In addition, a disperser for dispersing the fibers in the dielectric liquid or a supply device 3 for supplying the dielectric liquid may be arranged above the supply unit 4.

The discharge part usually has a drain pipe 61 connected to the bottom of the orientation part and a drain cock 62 connected to the drain pipe as shown in FIG. 1, for example. The shape, size, etc. of the supply unit, the orientation unit, and the discharge unit are not particularly limited, and various ones are selected depending on the purpose and application.

The positive and negative electrodes are at least a pair of electrodes provided in the alignment section 5 of the alignment tank 7 and extending in the vertical direction and spaced apart in the horizontal direction. The positive and negative electrodes are usually both plate-shaped, and two or more pairs of positive and negative electrodes may be alternately provided at regular intervals. As the material of the positive and negative electrodes, a commonly used material can be used, and for example, copper or the like can be used.

The filtration device is provided between the orientation section and the discharge section of the orientation tank and allows the dielectric liquid to pass therethrough to accumulate the fibers. The filtration device may have a filtration plate such as a porous ceramic filter.

A feature of this manufacturing apparatus is that the supply unit has a flow velocity decreasing resistance rectifying body for reducing the flow velocity of the dielectric liquid in which the fibers are injected and which is dispersed in the supply unit. The resistance rectifying body can prevent the agitation of the relatively large flow velocity of the liquid in the orientation tank in various directions such as the vertical or horizontal direction, which agitates the liquid in the orientation tank, and disperse the fibers appropriately. It is a thing.

The resistance rectifying body may have a horizontal impingement plate that changes the flow of the dielectric liquid in which the fibers are dispersed, which flows in from above, in the horizontal direction. The shape of the horizontal collision plate is not particularly limited, and may be, for example, the "V" shape 13 shown in FIG. 3 or the horizontal plate shape 13a shown in FIG.
Further, these horizontal collision plates may have holes having a desired shape.

The resistance rectifying body may be, for example, a drooping rectifying body 12b having a large number of through holes 14 in the vertical direction as shown in FIG. The hanging rectifying body has a through hole 14b guided substantially vertically as shown in FIG. 3 and a through hole 14a guided obliquely leftward as shown in FIG. 12 12
a, or 12c having both through holes 14a, 14b guided in the left diagonal direction and the right diagonal direction as shown in FIG.
Can be In particular, as shown in FIG. 4, when the dielectric liquid in which the fibers are dispersed is caused to flow into the injection port 16, the drooping rectifying body 12c may be used. Further, for example, as shown in FIG. 3, the one 12 having the horizontal collision plate and the hanging rectifying body 12b can be used together. In this case, since the vertical flow velocity of the liquid is reduced and the dispersion of the liquid is excellent,
More preferable.

In addition, as shown in FIG. 1, the manufacturing apparatus includes the positive and negative electrodes 8,
A high voltage applying device 11 for applying a high voltage may be provided between the terminals 9. The high voltage applying device 11 and the like are required to manufacture a fiber assembly in which most of the fibers are one-dimensionally oriented using the present manufacturing apparatus.

A fiber assembly in which most of the fibers are one-dimensionally oriented is manufactured by using this manufacturing apparatus, for example, as shown in FIG.

First, in the first step, fibers such as short fibers or whiskers are dispersed in a dielectric liquid, and the dielectric liquid is made to flow down to the inlet of the flow velocity reducing resistance rectifying body 12 using a beaker 3 or the like, so that the dielectric liquid This is a dispersion step of dispersing the fibers.

The fibers used in the dispersing step may be short fibers, whiskers, or mixed fibers of these fibers. As the whiskers and the short fibers, all those within the category of whiskers and short fibers can be used respectively, and the diameter and length thereof are not particularly limited. The material of the fibers may be one that electrostatically orients when a high voltage is applied between the positive and negative electrodes in a predetermined dielectric liquid. For example, as the material of the fiber, alumina, silica, alumina-
It may be silica, beryllia, carbon, silicon carbide, glass or various metals. Further, the fiber may be a mixed fiber of two or more fibers made of one of these materials.

The dielectric liquid is a liquid that exhibits a dielectric property when a high voltage is applied. As the dielectric liquid, carbon tetrachloride, fluorinated chlorine-substituted hydrocarbon, n-hexane, cyclohexane or the like can be used. Of these dielectric liquids, carbon tetrachloride is preferred. Fluorine-chlorinated hydrocarbons are preferable from the viewpoint of handling safety.

Depending on the type and state of the fiber, it is necessary to carry out a surface treatment of the fiber to loosen the fiber and release the aggregated state of the fiber. In order to disperse the fibers in the dielectric liquid, it is usually preferable to add an appropriate amount of a surfactant, especially a nonionic surfactant.

In the next second step, a dielectric liquid in which the fibers are dispersed is placed between positive and negative electrodes to which a high voltage is applied, and each of the fibers in the dielectric liquid has one end thereof as the positive electrode and the other end as the negative electrode. This is an alignment step of electrostatically aligning the film in the state of facing.

In the alignment step, normally about 1 to 15 KV is applied between the positive and negative electrodes.
Apply a high DC voltage. The high voltage is 1KV
Below, the electrostatic orientation force of the fiber is not sufficient, and above about 15 KV, the dielectric liquid is disturbed to disturb the oriented fiber, which is not preferable. The high voltage is about 1 to 10
About KV is preferable. This is because the electrostatic orientation force of the fiber is excellent and the dielectric liquid is less disturbed. In addition,
As the magnitude of the high voltage, the most preferable range is set variously depending on the dielectric properties of the fibers and the dielectric liquid used, the thickness of the fiber assembly to be produced, and the like.

Then, most of the individual fibers electrostatically oriented as described above cause bridging between the fibers in a one-dimensional direction perpendicular to the sedimentation direction of the fibers (hereinafter referred to as positive and negative electrode directions). Etc. settle down. It should be noted that the bridging fiber has a higher sedimentation rate than the non-bridging fiber.

Further, the next third step is a step of accumulating the fibers electrostatically oriented as described above in a state where the orientation state is maintained to obtain a fiber assembly in which the fibers are one-dimensionally oriented.

The accumulating step can be performed by allowing the fibers oriented in the orientation step to naturally settle by, for example, keeping the cock 62 arranged in the drain pipe 61 closed as shown in FIG. Further, in the collecting step, for example, in the apparatus shown in FIG. 1, the drain cock 62 of the discharge section 6 is opened so that the dielectric liquid containing the fibers oriented in the orientation step is changed to the orientation direction of the fibers. It can be performed by filtering in the vertical direction and collecting the oriented fibers 1a on the filter 10. According to this filtering method, the integration time can be shortened. Further, the filtration can be performed by suction or vacuum. Further, when this filter is arranged on the entire filtering surface and spontaneous sedimentation or filtration is performed, the disturbance of the liquid at the time of discharging the dielectric liquid can be suppressed, and therefore the orientation state of the oriented fiber is less disturbed, and therefore the primary It is possible to obtain a fiber assembly having a good original orientation. The filter may be made of porous ceramic or the like.

The dispersion step, the orientation step and the integration step may be continuously performed.

The fibrous aggregate accumulated in the accumulating step may be a mat-shaped aggregate having a relatively large thickness, a film-shaped aggregate having a relatively thin thickness, or the like.

A fiber assembly in which most of the fibers are one-dimensionally oriented is taken out from a predetermined device, and cut or laminated in the same shape or in a desired shape to obtain a reinforced fiber molded body for FRM.

[Advantageous Effects of the Invention] An apparatus for producing a one-dimensional oriented fiber assembly according to the present invention includes an orientation tank including a predetermined supply unit, an orientation tank and a discharge unit, a predetermined pair of positive and negative electrodes, a high voltage application device, and a predetermined voltage. And a manufacturing apparatus including the filtering device of (1) above, and a resistance rectifying body for reducing the flow velocity for reducing the flow velocity of the dielectric liquid injected into the supply unit.

Therefore, in the present manufacturing apparatus, when the dielectric liquid is injected into the apparatus, the flow velocity of the dielectric liquid is reduced, so that the liquid is not disturbed in the alignment tank. Therefore, the orientation state of the oriented fibers in the orientation tank is less disturbed, and the dispersion of the fibers in the supply section is uniform and good. Therefore, according to the present manufacturing apparatus, most of the fibers are good. Since a uniform fiber assembly with one-dimensional orientation and little deviation of the fibers can be obtained, when FRM is produced using this fiber assembly, extremely high strength and uniform strength are obtained in the direction of the one-dimensional orientation. FRM can be manufactured.

In the present manufacturing apparatus, since the fibers immediately after flowing into the apparatus exist in the supply section which is the upper part of the orientation tank of the apparatus, the settling time of the fibers becomes long, so that the one-dimensional orientation of the fibers becomes Further, the efficiency of integration is improved even if the orientation tank and the electrodes are made smaller.

Further, when the present manufacturing apparatus is used, a fiber aggregate in which most of the fibers are satisfactorily one-dimensionally oriented can be obtained, so that the entanglement of the fibers is small, and thus a fiber aggregate having a high fiber volume ratio can be obtained. Therefore, when manufacturing FRM using this fiber assembly, high strength FRM can be manufactured.

Further, according to this manufacturing apparatus, since the fibers are also less entangled with each other, it is possible to obtain a fiber assembly with less springback. Therefore, an FRM product with high accuracy can be obtained by using the fiber assembly manufactured using this apparatus.

[Examples] Hereinafter, the present invention will be described with reference to Examples.

Alumina short fibers without surface treatment (average diameter about 3μ, length 10-500μ) are added to a dielectric liquid of carbon tetrachloride together with a very small amount of nonionic surfactant, and these are stirred to disperse the fibers. Let

Next, the manufacturing apparatus shown in FIG. 1 is prepared. The apparatus is supplied with a flow velocity reducing resistance rectifying body 12 for injecting the dispersion liquid, and a dielectric liquid 2 in which fibers such as short fibers 1 are dispersed upward through the resistance rectifying body 12 and supplies the dielectric liquid downward. And a discharge part 6 for discharging the dielectric liquid 2 downward, and the dielectric liquid 2 between the supply part 4 and the discharge part 6.
An alignment tank 7 having an orienting part 5 that moves downward, and a pair of positive electrodes 8 provided in the orienting part 5 of the orienting tank 7 and extending in the vertical direction and spaced apart in the horizontal direction. In order to apply a high voltage between the negative electrode 9, a penetration device 10 provided between the orientation part 5 and the discharge part 6 for passing the dielectric liquid and collecting the fibers, and a high voltage between these electrodes 8 and 9. The high voltage applying device 11 of FIG. The resistance rectifier 12
Has a funnel-shaped upper part and a horizontal impact plate 13 connected to its lower part. The distance between the electrodes is 40 mm. Further, the introducing device 10 is composed of a porous ceramic filter.

Put carbon tetrachloride between the electrodes in the electrostatic orientation device, and
A DC voltage of V is applied and the fiber 1
The dielectric liquid 2 dispersed in the beaker 3 is placed in the beaker 3 and injected into the upper end of the resistance rectifying body 12, and then the dielectric liquid is injected into the horizontal collision plate.
Colliding with 13, its flow was changed and dispersed horizontally,
It flowed into the supply section 4.

Next, the injected fibers 1 are dielectrically polarized in the dielectric liquid 2 and electrostatically oriented so that one end thereof faces the positive electrode 8 and the other end faces the negative electrode 9. This electrostatically oriented fiber 1a
When most of them settle, bridging occurs in most of them, and the fibers and the like that have bridged settle in a state where they are oriented in a one-dimensional direction toward the positive and negative electrodes.

The electrostatically oriented fiber 1a as described above is filtered through the filter 10 to the dielectric liquid by opening the drain cock 62 provided in the drain pipe 61 while maintaining the orientation state, and the fiber is It is integrated on the filter 10 in a one-dimensional orientation.

Then, the dispersion step, the orientation step, and the accumulation step are sequentially performed to form a predetermined fiber aggregate, and the dielectric liquid remaining in the apparatus is removed through the drain pipe 61 to produce a mat-shaped fiber aggregate 15. did.

As shown in FIG. 1, the apparatus of this embodiment has a flow velocity reducing resistance rectifier 12 having a horizontal collision plate 13 for reducing the flow velocity of the dielectric liquid injected into the supply section. Therefore, when the dielectric liquid is injected into the device, the flow velocity of the dielectric liquid in the vertical direction is reduced, and the flow is changed in the horizontal direction, so that the dispersibility of the fiber is good.

Therefore, according to this apparatus, a uniform fiber assembly in which many of the fibers are well one-dimensionally oriented and the fibers are not biased can be obtained.

Furthermore, since the fiber assembly in this example is a fiber assembly in which the fibers are one-dimensionally oriented, the fiber assembly rate is higher than that of the conventional one, and a fiber assembly with less springback can be obtained, and therefore the accuracy is improved. High FRM can be manufactured.

Further, since the present manufacturing apparatus has a corrosion-resistant porous filter disposed on the entire bottom surface of the apparatus when accumulating the oriented fibers, the turbulent flow of the liquid generated when the liquid is discharged is obtained by using the present manufacturing apparatus. Therefore, since the orientation of the fibers is not disturbed, a fiber assembly having good orientation of the fibers can be manufactured.

Further, since the filtrate can be continuously discharged and removed through the drain pipe by using this manufacturing apparatus, the fibers can be accumulated in a short time.

[Brief description of drawings]

FIG. 1 is an explanatory cross-sectional view of a manufacturing apparatus having a flow velocity reducing resistance rectifying body having a horizontal collision plate according to the embodiment. Second
The figure is an explanatory cross-sectional view of a manufacturing apparatus having a drooping rectifying body.
FIG. 3 is an explanatory sectional view of a manufacturing apparatus having a flow velocity reducing resistance rectifying body having a horizontal collision plate and a drooping rectifying body. Fourth
The drawing is an explanatory cross-sectional view of a manufacturing apparatus in which a dielectric liquid in which fibers are dispersed is injected into a supply portion from a lateral direction and which has a hanging rectifier. FIG. 5 is a sectional view showing another example of the flow velocity reducing resistance rectifying body having a horizontal collision plate. FIG. 6 is an explanatory cross-sectional view of a state in which a conventional dielectric liquid in which fibers are dispersed is poured into a supply unit. FIG. 7 is a partially cutaway sectional view of a conventional centrifugal molding apparatus.
FIG. 8 is an explanatory sectional view of a conventional suction molding device. 1 ... Fiber, 1a ... Oriented fiber 2 ... Dielectric liquid 3 ... Fiber dispersion liquid supply device 4 ... Receiving unit, 5 ... Orientation unit 6 ... Ejection unit, 10 ... Filter 61 ... Drain pipe, 62 …… Drain cock 7 …… Orientation tank, 8 …… Positive electrode 9 …… Negative electrode, 11 …… High voltage application device 12 …… Flow rate reducing resistance rectifier 13 …… Horizontal collision plate, 14 ・ ・ ・… Suspended rectifier 15 …… Fiber aggregate, 16 …… Injection port 21 …… Outer cylinder, 22 …… Drain hole 23 …… Perforated cylindrical container, 24 …… Supply pipe 25 …… Filtration membrane 26 …… Silicon carbide whisker Hollow molded body 31 …… Cylinder 32 …… Pressurized plunger 33 …… Filtration material, 34 …… Fiber mixed liquid

Claims (3)

[Claims] 1. A supply unit for supplying a dielectric liquid in which fibers such as whiskers and short fibers are dispersed upward and supplying the dielectric liquid downward, and a discharge unit for discharging the dielectric liquid downward, and the supply unit. And an alignment part having an alignment part in which the dielectric liquid moves downward between the discharge part and the discharge part; and an alignment part provided in the alignment part of the alignment part, each extending in the vertical direction and spaced apart in the horizontal direction. And a pair of positive electrodes and a negative electrode, and a passing device which is provided between the orientation part and the discharge part of the orientation tank and allows the dielectric liquid to pass therethrough to accumulate the fibers. 2. The manufacturing apparatus for an oriented fiber assembly, wherein the supply unit has a flow velocity decreasing resistance rectifying body for reducing the flow velocity of the dielectric liquid injected into the supply unit. 2. The flow velocity reducing resistance rectifying body according to claim 1, wherein the resistance rectifying body has a horizontal impinging plate for horizontally changing the flow of the dielectric liquid in which the fibers are dispersed, which flows in from above the resistance rectifying body. Equipment for manufacturing oriented fiber assembly. 3. The apparatus for producing an oriented fiber assembly according to claim 1, wherein the flow velocity reducing resistance rectifying body is a drooping rectifying body having a large number of through holes in the vertical direction.