JPH08196980A - Method and apparatus for making prepreg - Google Patents

Abstract

PURPOSE: To provide a method and apparatus in which the supply of a synthetic resin liquid to a bundle of fibers is stabilized even for the change of the velocity and tension of threads of the bundle, the high permeability of the resin liquid into the bundle is kept, and the solid in the resin liquid does not precipitate to the bottom of a resin impregnation tank. CONSTITUTION: A bundle 4 of fibers received from a take-up package 1 is impregnated with a synthetic resin liquid 3 applied on the surface of a resin impregnation roll 8, and the bundle 4 impregnated with the resin liquid is received by a receiving means 6 to form a prepreg. During receiving, the relationship between the receiving velocity of the means 6 and the circumferential velocity of the roll 8 is kept to be 0.9<=V2/V1<1, where V1 (m/min), is the receiving velocity, and V2 (m/min) is the circumferential velocity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a prepreg for a composite material and an improvement in the apparatus therefor, and more specifically to a method for manufacturing a prepreg which employs a so-called wet method as a method for impregnating a fiber bundle with a synthetic resin liquid. Regarding the improvement of the device.

[0002]

2. Description of the Related Art Conventionally, as a method of impregnating carbon fiber, glass fiber and the like with a synthetic resin liquid in a manufacturing process of a prepreg sheet, there are employed two methods, a so-called wet method and a hot melt method (dry method). However, the latter wet method is generally widely used because the equipment is relatively simple and the manufacturing cost is low.

(1) The conventional typical wet method manufacturing apparatus is shown in FIG.
The fiber bundle 4 pulled out from the winding package 1 is a device described in Japanese Patent No. 15 publication, and a synthetic resin 3 is formed by a resin impregnating roll 8 provided in a state in which a part of the roll surface is immersed in a synthetic resin tank 2. Is given. The fiber bundle 4 to which the synthetic resin liquid 3 is applied is taken up by the take-up means 6 to form a prepreg sheet.

(2) The apparatus shown in FIG. 10 also shows such a conventional wet method apparatus, in which the fiber bundle 4 pulled out from the winding package 1 is provided in the synthetic resin tank 2. It is directly immersed in the synthetic resin liquid 3 by the fixed holding bar 7. Fiber bundle 4 impregnated with synthetic resin liquid 3
Is squeezed by a plurality of squeeze pins 5 arranged on the upper part of the resin to scrape off excess resin liquid,
The squeeze pin is widened in the axial direction to form a tape. The tape-shaped fiber bundle 4 with synthetic resin liquid is used as the take-up means 6
To manufacture prepreg sheets.

[0005]

However, in the above prior art (1), the resin impregnating roll is driven by the running of the fiber bundle due to the friction between the fiber bundle 4 and the surface of the resin impregnating roll 8. At the time of starting the pulling means 6 (start of pulling) and ending the start (end of pulling), the resin impregnating roll 8 did not accurately follow the fiber bundle due to the inertia of the resin impregnating roll. Therefore, there is a drawback that the amount of resin applied from the resin impregnating roll 8 to the fiber bundle is not stable. Also, for example, when a means for driving the resin impregnating roll by a motor or the like so that the resin impregnating roll accurately follows the fiber bundle and rotates, the synthetic resin liquid 3
Was applied only to the surface where the fiber bundle was in contact with the resin impregnating roll, and did not penetrate into the single yarn of the fiber bundle. As a result, a part of the formed prepreg sheet that was not sufficiently impregnated with the synthetic resin liquid was generated, and the quality of the prepreg sheet was bad.

On the other hand, in the above-mentioned prior art (2), the fiber bundle 4 directly passes through the resin impregnation tank 2, the synthetic resin liquid in the impregnation tank is supplied to the fiber bundle in a dipped state, and then the squeeze pin 5 is used. Since the resin supply amount is controlled by scraping off the excess resin, the speed of the fiber bundle (the take-up speed of the take-off means) at the start of the take-up means 6 (start of pulling) and at the end of the start (end of pulling) ) From 0 to normal operating speed,
Or, when the normal operating speed changes to 0 and the yarn tension between the squeeze pins changes accordingly, the amount of resin liquid scraped by the squeeze pins 5 changes,
There is a drawback that the amount of resin adhered to the fiber bundle 4 is not stable.

Further, as a component of the synthetic resin liquid 3, for example,
When the resin liquid contains solids such as rubber components, the solids do not dissolve in the solvent, so that the solids will settle at the bottom of the resin impregnation tank 2 due to long-term use. There is also a problem that the components of the resin liquid that adheres gradually change and the amount of resin adhered gradually decreases.

The present invention solves the above-mentioned drawbacks of the prior art and stabilizes the resin supply amount even if the yarn speed or yarn tension changes.
Further, the present invention provides a method and an apparatus for producing a prepreg in which the resin is sufficiently impregnated even between the single yarns constituting the fiber bundle, and further, the solid content in the resin does not settle at the bottom of the resin impregnation tank even when used for a long time. With the goal.

[0009]

In order to achieve the above object, the method for producing a prepreg of the present invention is such that a synthetic resin is applied to a fiber bundle by a resin impregnating roll, and then the fiber bundle is taken up by a take-up means. A prepreg manufacturing method for manufacturing a prepreg sheet, comprising: a take-up speed V1 of the take-up means.
(M / min) and the peripheral speed of the resin impregnating roll V2 (m / min)
Min.) With a velocity relationship of 0.9 ≦ V2 / V1 <1 to draw the fiber bundle by a take-up means to produce a prepreg sheet. In this case, the speed relationship between the take-up speed of the take-up means and the peripheral speed of the resin impregnating roll is as follows: the take-up speed of the take-up means is V1 (m / min),
When the peripheral speed of the resin impregnating roll is V2 (m / min), it is preferable to set the relationship of 0.9 ≦ V2 / V1 <1.

The prepreg manufacturing apparatus of the present invention for achieving the above object is a resin impregnation tank for receiving a synthetic resin liquid, and is rotatable in a state where a part of the roll surface is immersed in the resin impregnation tank. A roll for resin impregnation provided in, and a manufacturing device of a prepreg consisting of a take-up unit for taking up the fiber bundle impregnated with the synthetic resin liquid, between the roll for impregnating the resin and the take-up device, A speed adjusting means is provided for maintaining the peripheral speed (V1) of the resin impregnating roll and the take-up speed (V2) of the take-up device in a speed relationship of 0.9 ≦ V2 / V1 <1. In this case, it is preferable to provide a stirrer driven by the resin impregnating roll inside the resin impregnating tank. Further, it is more preferable to provide a resin film thickness adjusting plate which is close to the outer peripheral surface of the resin impregnating roll and is movable back and forth in the roll surface direction.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the prepreg manufacturing apparatus of the present invention will be specifically described below with reference to the drawings.

1 and 2 are schematic side views of a prepreg manufacturing apparatus according to the present invention, FIG. 3 is an enlarged perspective view of a resin impregnating roll in FIGS. 1 and 2, and FIG. 4 is FIG. 1 and FIG. It is an expanded longitudinal cross-sectional view of the resin film thickness adjusting plate in 2.

In FIG. 1, 1 is, for example, carbon fiber,
A winding package 2 in which a fiber bundle 4 such as glass fiber is wound, 2 is a resin impregnation tank for receiving a synthetic resin liquid 3 such as an epoxy synthetic resin or phenol synthetic resin dissolved in a solvent, and 8 is a resin A resin impregnating roll for adhering the resin liquid 3 to the roll surface from the impregnation tank 2 and pumping it up, applying it to the fiber bundle 4 and impregnating it inside the fiber bundle. The drive shaft 8a of the resin impregnating roll 8 is supported by a bearing (not shown) in such a positional relationship that a part of the outer peripheral surface thereof is immersed in the resin liquid. In this embodiment, the resin impregnating roll 8 is used.
The drive shaft 8a is driven by a motor (not shown) provided on the winding drum 6 described later.

Reference numeral 11 denotes an agitator for agitating the synthetic resin liquid 3, and as shown in FIG. 3, a gear 8b provided on both ends of the resin impregnating roll 8 and a gear 11 provided on the agitator 11.
and a are engaged with each other and are forcedly driven. The embodiment shown in FIG. 3 is an example, and the drive source may not be driven by the resin impregnating roll 8 but may be rotated by an independent motor.

Returning to FIG. 1, pressing pins 9 for winding the fiber bundle 4 on the surface of the resin impregnating roll 8 for a predetermined length are provided on both sides of the resin impregnating roll 8. In addition, 10 is a resin film thickness adjusting plate for scraping the resin liquid adhering to the surface of the resin impregnating roll to a predetermined thickness, and as shown in FIG. 4, its tip is formed into a sharp knife shape, The push bolt 10a can be moved back and forth in the roll axial direction.

6 is a fiber bundle 4 formed into the above tape shape.
A take-up drum that is a take-up unit for taking up a sheet-shaped prepreg by winding the sheet on a drum surface, and includes a motor such as an induction motor or a synchronous motor (not shown) and a traverse device, and traverses in the drum axial direction. While being able to rotate in the direction of the arrow in the figure. The traverse device may be provided independently of the winding drum, and such an aspect is also included in the present invention.

Reference numeral 12 is a speed adjusting means for adjusting the peripheral speed on the surface of the winding drum 6 and the peripheral speed on the surface of the resin impregnating roll 8 so as to have a predetermined speed ratio. As a preferable speed ratio between both speeds, when the peripheral speed of the winding drum 6 is V1 and the peripheral speed of the resin impregnating roll 8 is V2,
The relationship is 0.9 ≦ V2 / V1 <1, that is, the peripheral speed of the resin impregnating roll is controlled within −10% of the peripheral speed of the winding drum. As such a speed adjusting means,
As in the present embodiment, the resin impregnating roll 8 and the winding drum 6 may be connected by a mechanical means such as a gear transmission, a pair of chain wheels having the number of teeth set to the above speed ratio, and a timing belt. When the impregnating roll 8 and the winding drum 6 are provided with independent induction motors, synchronous motors, etc., these two motors may be electrically connected by an inverter, a frequency setter, or the like.

The prepreg manufacturing method of the present invention is carried out as follows using the apparatus described above.

When a motor (not shown) of the winding drum 6 is driven, traverse is started while the winding drum rotates, and at the same time, the resin impregnating roll 8 also rotates to pull out the fiber bundle 4 from the winding package 1. On the other hand, the synthetic resin liquid 3 adhering to the surface of the resin impregnating roll by rotation and being scraped up is scraped to a predetermined thickness by the resin film thickness adjusting plate 10 shown in FIG. 4, and the resin supply amount is adjusted. . When the synthetic resin liquid 3 reaches the front side of the top of the resin impregnating roll, the synthetic resin liquid 3 comes into contact with the fiber bundle 4 and the resin liquid is applied to the fiber bundle. Since the resin impregnating roll rotates at a peripheral speed of 0.9 to 1 times the yarn speed, friction occurs between the resin impregnating roll surface and the fiber bundle, and the fiber bundle is widened in the width direction to form a tape shape. It becomes a fiber bundle. That is, the fiber bundle is opened, the resin liquid sufficiently penetrates into the single yarns, and the fiber bundle is sufficiently impregnated with the resin liquid. Thereafter, the tape-shaped fiber bundle 4 is wound into a sheet by the winding drum 6 that rotates while traversing to form a prepreg. In this case, since the resin impregnating roll 8 and the winding drum 6 rotate in conjunction with each other while maintaining a predetermined speed ratio from the beginning of winding to the end of winding, as shown in FIG. At the end of winding, when the yarn speed of the fiber bundle 4 changes due to the acceleration and deceleration of the winding drum, and the yarn tension changes accordingly, the amount of resin adhered to the fiber bundle 4 in the resin impregnation tank 2 remains constant. Become.

Here, it is not preferable to set the peripheral speed of the resin impregnating roll 8 higher than the yarn speed because the fiber bundle 4 will sag between the resin impregnating roll and the winding drum. Further, when the speed difference between the yarn speed and the peripheral speed of the resin impregnating roll is large, the friction between the resin impregnating roll surface and the fiber bundle also becomes large, so that the amount of fluff generated as shown in Table 1 below. Will increase.

[0021]

[Table 1] Therefore, for the above reason and Table 1, the peripheral speed of the resin impregnating roll 8 is preferably controlled within the range of 0.9 to 1 times the yarn speed as described above.

Further, since the stirrer 11 is installed in the resin impregnation tank 2, the resin solid content is high even at a low yarn speed of 10 m / min or less where the resin solid content is likely to settle. It is possible to obtain a prepreg with a stable resin adhesion amount for a long time without precipitation. Since the stirrer 11 is driven by the resin impregnating roll 8, it does not require a dedicated power as compared with a conventional stirrer using a pump or the like. It is therefore economical.

In this embodiment, the take-up means traverses the take-up drum 6 as described above, but a calendar roll system as shown in FIG. 2 may be used instead. In that case, a plurality of fiber bundles 1a, 1b, 1c
It is possible to manufacture a prepreg sheet without using a traverse device even if the prepreg sheets are simultaneously taken.

[0024]

In the method and apparatus for producing a prepreg of the present invention, a fiber bundle is drawn by the drawing means in a predetermined relationship by providing a speed difference between the drawing speed of the drawing means and the peripheral speed of the resin impregnating roll. Therefore, unlike the prior art, the resin liquid does not adhere only to the surface where the fiber bundle is in contact with the resin impregnating roll,
Further, the relative speed between the peripheral speed of the resin impregnating roll and the yarn speed does not change at the beginning or the end of the pulling of the take-up means. Therefore, it is possible to manufacture a prepreg sheet of stable quality, which does not have a resin unimpregnated portion in the fiber bundle or a variation in the amount of resin attached.

[0025]

Examples and Comparative Examples Examples 1 to 3 In FIG. 1, the resin impregnating roll 8 has an outer diameter of 300 m.
The outer diameter of the winding drum 6 was 600 mm. Further, the gap between the resin film thickness adjusting plate 10 and the resin impregnating roll 8 is 0.
It was set to 4 mm. Then, independent motors with speed controllers were used as driving means for the resin impregnating roll 8 and the winding drum 6, and the rotation speed of each motor was controlled using an inverter. The rotation speed of the resin impregnating roll 8 is 90 rpm, that is, the peripheral speed V2 of the resin impregnating roll is 85 m / min, and the rotation speed of the winding drum 6 is 50 r.
pm, that is, the yarn speed V1 is set to 94 m / min.
The prepreg sheet 13 having the dimensions shown in FIG. 6 was manufactured by the prepreg manufacturing apparatus. Then, as shown in FIG. 7, this prepreg sheet was cut into 24 pieces, and the weight of each piece was measured, and the variation σ / m
[%] (Where σ is the standard deviation of individual piece weights, m
Is the average value of the individual piece weights. ) Was calculated.

Comparative Examples 1 to 3 On the other hand, using the conventional apparatus of FIG. 10, the peripheral speed V1 of the winding drum 6, that is, the yarn speed is set to 94 m / min, and other conditions are exactly the same as those of Examples 1 to 3. The prepreg sheet 13 was manufactured under the conditions, and the weight variation of 24 pieces was measured in the same manner.

Table 2 below shows the actual measurement results of variations and the average values of the variations in Examples 1 to 3 and Comparative Examples 1 to 3.

[0028]

[Table 2] According to this Table 2, the prepreg sheet produced by the method and apparatus of the present invention has a piece weight variation range of 0.61 to 0.78%, while the conventional method produces 1.01. Since it is about 1.30%, it means that it is improved by about 40% as compared with the conventional method.

Example 4, Comparative Example 4 In the apparatus of the present invention shown in FIG. 1, prepreg sheets were produced under the same conditions as in Examples 1 to 3, and at that time, the fiber bundle immediately after being unwound from the winding package. And the width of the fiber bundle on the surface of the resin impregnating roll are measured in Example 4 in Table 3.

On the other hand, when the prepreg sheet is manufactured by the conventional method of FIG. 9 in which there is no speed difference between the yarn speed of the fiber bundle and the peripheral speed of the resin impregnating roll, the fiber bundle immediately after being unwound from the winding package. And the width of the fiber bundle when it is on the surface of the resin impregnating roll is Comparative Example 4 in Table 3.

According to Table 3, the fiber bundles compared without making a speed difference between the yarn speed of the fiber bundles and the peripheral speed of the resin impregnating roll have a width which is not rubbed on the resin impregnating roll surface. Shows that the fiber bundle according to the method of the present invention operated by applying a speed difference between the yarn speed of the fiber bundle and the peripheral speed of the resin-impregnated roll is widened and opened on the resin-impregnated roll surface. I know that

[0032]

[Table 3] Example 5, Comparative Example 5 In the apparatus of the present invention in FIG. 1, the agitator 11 has an outer diameter of 80.
mm and a 6-blade impeller. Using this apparatus, the prepreg sheet 13 was manufactured under the same conditions as in Examples 1 to 3, and the change in weight was measured every 10 minutes and plotted in Example 5 in FIG.

On the other hand, the agitator 11 is not installed in FIG.
The weight change of the prepreg sheet manufactured by the conventional method is plotted in Comparative Example 5 in FIG.

According to FIG. 8, the weight of the prepreg sheet compared without the stirrer 11 is decreased because the resin solid content is gradually precipitated, but the stirrer 11 is installed. It can be seen that the prepreg sheet produced by the method of the present invention produced by the above method is excellent in quality without any change in its weight over time.

[0035]

According to the present invention, the following effects can be obtained.

(1) According to the first and second aspects of the present invention, the instability of the amount of resin adhered to the prepreg by the conventional dipping method can be eliminated, so that from the beginning to the end of pulling the fiber bundle to the pulling means. A stable prepreg sheet having no variation in the amount of resin adhered can be obtained over the entire range of. Further, since the fiber bundle is widened and opened by the friction generated between the surface of the resin impregnating roll and the fiber bundle, and the resin liquid penetrates into the single yarns, a high-quality prepreg sheet with good resin impregnation property is obtained. Is obtained.

(2) According to the invention of claim 3, since the synthetic resin liquid in the resin tank is agitated by the agitator, the resin solid content does not precipitate. Therefore, the amount of resin adhering to the fiber bundle is constant even when operating for a long time, and a prepreg sheet of excellent quality can be obtained.

(3) According to the invention of claim 4, since the resin film thickness adjusting plate is provided which can advance and retreat in the surface direction of the resin impregnating roll, the variation in the resin supply amount to the fiber bundle is further stabilized, A prepreg sheet of excellent quality can be manufactured.

[Brief description of drawings]

FIG. 1 is a schematic side view of a prepreg manufacturing apparatus according to the present invention.

FIG. 2 is a schematic side view of a prepreg manufacturing apparatus according to the present invention.

FIG. 3 is an enlarged perspective view of a resin impregnating roll and a stirrer in FIG.

4 is an enlarged vertical sectional view of a resin film thickness adjusting plate in FIG.

FIG. 5 is a diagram showing a change in peripheral speed during winding of the winding drum and the resin impregnating roll in FIG.

FIG. 6 is a perspective view of a prepreg sheet obtained by the manufacturing method and apparatus of the present invention.

FIG. 7 is a perspective view showing a cutting dimension of a prepreg piece.

FIG. 8 is a diagram illustrating a change over time in the weight of a prepreg sheet.

FIG. 9 is a schematic vertical sectional view of a conventional device.

FIG. 10 is a schematic vertical sectional view of a conventional device.

[Explanation of symbols]

 1: winding package 2: resin impregnation tank 3: synthetic resin liquid 4: fiber bundle 5: squeeze pin 6: take-up means 7: pressing bar 8: resin impregnating roll 9: pressing pin 10: resin film thickness adjusting plate 11: Stirrer 12: Speed adjusting means 13: Prepreg sheet

Claims (4)

[Claims] 1. A method of manufacturing a prepreg, which comprises applying a synthetic resin to a fiber bundle with a resin impregnating roll, and then taking the fiber bundle by a take-up means to produce a prepreg sheet, wherein a take-up speed V1 of the take-up means is used. (M / min) and the peripheral speed V2 (m / min) of the resin impregnating roll, 0.9 ≦ V2 /
A method for producing a prepreg, which comprises producing the prepreg sheet by pulling the fiber bundle with a take-up means while having a velocity relationship of V1 <1. 2. A resin impregnating tank for receiving a synthetic resin liquid, a resin impregnating roll rotatably provided with a part of the roll surface immersed in the resin impregnating tank, and the synthetic resin liquid impregnated. A device for manufacturing a prepreg, comprising: a take-up device for taking out the fiber bundles, wherein a peripheral speed (V1) of the resin-impregnating roll and the take-up device are provided between the resin-impregnating roll and the take-up device. The velocity (V2) is 0.
An apparatus for manufacturing a prepreg, comprising speed adjusting means for maintaining a speed relationship of 9 ≦ V2 / V1 <1. 3. The prepreg manufacturing apparatus according to claim 2, wherein an agitator driven by the resin impregnating roll is provided inside the resin impregnating tank. 4. A prepreg manufacturing apparatus according to claim 3, further comprising a resin film thickness adjusting plate which is disposed close to the outer peripheral surface of the resin impregnating roll and is movable back and forth in the roll surface direction. .