JP7093073B2 - Manufacturing method and manufacturing equipment for thermoplastic resin composite materials - Google Patents

Description

The present invention relates to a method and an apparatus for manufacturing a thermoplastic resin composite material.

Conventionally, a thermoplastic resin composite material including an extruder in which a thermoplastic resin and a reinforcing fiber are kneaded and extruded under heating, and a press machine in which an extruder (molding material) extruded from the extruder is molded and molded. Manufacturing equipment is known (see, for example, Patent Document 1).
In such an apparatus for producing a thermoplastic resin composite material, the thermoplastic resin supplied to the extruder and melted is kneaded with the reinforcing fibers. The extruder extrudes this kneaded product into a flat plate from a die having a predetermined opening width. Then, the extruded product (molding material) is supplied into the mold of the press machine and molded to produce a thermoplastic resin composite material (molded product) having a predetermined shape.

Japanese Unexamined Patent Publication No. 2006-327214

By the way, in the method for manufacturing a thermoplastic resin composite material using a conventional manufacturing apparatus (see, for example, Patent Document 1), a molding material is used for the purpose of improving the fluidity of the molding material having a relatively high viscosity in a mold. There is a request to set the temperature of the product high. However, considering the deterioration of the thermoplastic resin due to overheating, the heating temperature of the molding material is limited to a low level. Further, the mold temperature is also limited to a low level because it is necessary to sufficiently solidify the molded product at the time of demolding. Therefore, it is extremely difficult to increase the flow distance of the molding material in the mold by the conventional manufacturing method.
Further, in the conventional manufacturing method, non-uniform shrinkage is generated in the molded product after demolding due to the pressure distribution and the temperature distribution generated in the molding material in the mold. Therefore, the obtained molded product has a problem that the deformation such as warpage is relatively large.

Therefore, the subject of the present invention is that it is possible to improve the fluidity of the molding material in the mold while preventing overheating of the thermoplastic resin, and the amount of deformation such as warpage of the thermoplastic resin composite material as a molded product. It is an object of the present invention to provide a manufacturing method and a manufacturing apparatus of a thermoplastic resin composite material capable of reducing the above.

The method for producing a thermoplastic resin composite material of the present invention, which solves the above-mentioned problems, is a method for producing a thermoplastic resin composite material in which reinforcing fibers are dispersed in a thermoplastic resin, and the thermoplastic resin and the reinforcing fibers are heated under heating. A premolding step of kneading and extruding the kneaded material through an opening having a predetermined shape to form a preformed body having a cross-sectional shape that follows the shape of the opening, and molding the preformed body in a mold. It also has a press molding step of molding the thermoplastic resin composite material having a predetermined shape.
The first width of the opening corresponding to the mold clamping direction of the preformed body is non-uniform over the second width of the opening in the direction intersecting the first width, and the shape of the opening is as follows. At least one end in the extending direction of the second width has the first width larger than the central portion in the extending direction of the second width, and from the central portion side toward the portion side having the larger first width. The first width is formed in a tapered shape, and the opening is characterized by having a rectangular portion as the central portion .

Further, the apparatus for producing a thermoplastic resin composite material of the present invention is an extruder in which a thermoplastic resin and a reinforcing fiber are kneaded and extruded under heating, and an extruder extruded from the extruder is mold-clamped to be thermoplastic. A device for producing a thermoplastic resin composite material including a press machine for forming a resin composite material, wherein the opening of the die of the extruder to which the extruded product is extruded corresponds to the mold clamping direction of the extruded product. The first width of the opening is non-uniform over the second width of the opening in the direction intersecting the first width, and the shape of the opening is such that at least one end in the extending direction of the second width is. The first width is larger than the central portion in the extending direction of the second width, and the first width is formed in a tapered shape in which the first width increases from the central portion side toward the portion where the first width is large. The opening is characterized by having a rectangular portion as the central portion .

According to the present invention, the thermoplastic resin composite improves the fluidity of the thermoplastic resin in the mold while preventing overheating of the thermoplastic resin, and reduces the amount of deformation of the obtained thermoplastic resin composite material. It is possible to provide a method for manufacturing a material and a manufacturing apparatus.

It is a block diagram of the manufacturing apparatus of the thermoplastic resin composite material which concerns on embodiment of this invention. It is a partial cross-sectional view of the extruder which constitutes the manufacturing apparatus of a thermoplastic resin composite material. It is a front view (end view) of the die of an extruder, and is the figure which includes the cross section of an extruder. It is a graph which shows the relationship between the temperature of a molding material from the start of molding in a mold, after demolding, to cooling to room temperature, and the specific volume of a molding material. It is a schematic diagram for demonstrating the flow pattern of the molding material by molding. (A) shows the flow pattern of the Example of this invention, and (b) shows the flow pattern of the comparative example. (A) and (b) are structural explanatory views of the preformed body which concerns on a modification. It is a perspective view of the molding material used for the verification of the action and effect | effect which the manufacturing method of the thermoplastic resin composite material of this invention plays. (A) is a perspective view of the molding material used in the examples, and (b) is a perspective view of the molding material used in the comparative example. (A) is a plan view of the preformed body (molding material) used in the examples, and (b) is a plan view of the preformed body (molding material) used in the comparative example. It is a comparative figure of the flow distance after the elapse of 1.60 [sec] from the start of mold clamping, in the preformed body of an Example and the preformed body of a comparative example. In the comparative diagram of the flow distances of the preformed body of the example and the preformed body of the comparative example after 10.70 [sec] has elapsed in the example and 10.80 [sec] have elapsed in the comparative example from the start of mold clamping. be. It is a comparative figure of the flow distance after 12.00 [sec] elapses from the start of mold clamping, in the preformed body of an Example and the preformed body of a comparative example. In the comparison diagram of the flow distance between the preformed body of the example and the preformed body of the comparative example after 16.01 [sec] has elapsed in the example and 16.00 [sec] has elapsed in the comparative example from the start of mold clamping. be. (A) is a plan view showing the temperature distribution in the preformed body of the example after mold clamping and filling, and (b) is a plan view showing the temperature distribution in the preformed body of the comparative example after mold clamping and filling. (A) is a plan view showing the pressure distribution in the preformed body of the example after mold clamping and filling, and (b) is a plan view showing the pressure distribution in the preformed body of the comparative example after mold clamping and filling. (A) is a plan view showing the warp amount distribution of the molded product (thermoplastic resin composite material) of the example after demolding, and (b) is the molded product (thermoplastic resin composite material) of the comparative example after demolding. ) Is a plan view showing the warp amount distribution.

Next, an apparatus for producing a thermoplastic resin composite material according to an embodiment of the present invention and a method for producing a thermoplastic resin composite material using the apparatus will be described in detail. In the following, the thermoplastic resin composite material will be described first, and then the manufacturing apparatus and the manufacturing method will be described.

≪Thermoplastic resin composite material≫
The thermoplastic resin composite material in the present embodiment is mainly composed of a thermoplastic resin and reinforcing fibers.
Examples of the thermoplastic resin include crystalline resins such as high-density polyethylene, low-density polyethylene, polypropylene, polyamide resin, polyacetal, polyethylene terephthalate, polybutylene terephthalate, polyphenylene sulfide, and polyether ether ketone; polystyrene, polyvinyl chloride, and AS. Examples thereof include, but are not limited to, non-crystalline resins such as resins, ABS resins, acrylic resins, polycarbonates, and modified polyphenylene ethers. Of these, polyamide resin is preferable.

Reinforcing fibers include, for example, inorganic fibers such as glass fiber, carbon fiber, boron fiber, and metal fiber (eg, stainless fiber, aluminum fiber, copper fiber, etc.), polyparaphenylene terephthalamide fiber, and polymetaphenylene terephthal. Total aromatic polyamide fiber such as amide fiber, polyparaphenylene isophthalamide fiber, polymethaphenylene isophthalamide fiber, fiber obtained from a condensate of diaminodiphenyl ether and terephthalic acid or isophthalic acid, total aromatic liquid crystal polyester fiber, etc. Organic type, but not limited to these. Of these, carbon fiber is preferable. The carbon fiber may be either PAN-based or pitch-based.
Such reinforcing fibers can also be surface-treated with a coupling agent or the like to improve the adhesiveness with the thermoplastic resin. Further, the reinforcing fiber may also contain a sizing agent made of a polymer or the like.

Further, various additives can be further contained in the thermoplastic resin composite material.
Known additives can be used, and examples thereof include, but are not limited to, colorants, flame retardants, antioxidants, stabilizers, ultraviolet absorbers, and antistatic agents. ..

The content of the reinforcing fiber with respect to the thermoplastic resin in the thermoplastic resin composite material can be appropriately set according to the use of the thermoplastic resin composite material. For example, when a thermoplastic resin composite material is used as a component for a vehicle, the volume fraction (Vf) of carbon fibers is preferably 20% or more and 60% or less. The volume fraction (Vf) of this carbon fiber is synonymous with the fiber volume fraction (Vf) defined in JIS K 7035 (2014).

As will be described later, such a thermoplastic resin composite material is obtained by press-molding a melt-kneaded product containing the above-mentioned thermoplastic resin, reinforcing fibers, and the like in a predetermined amount.
The thermoplastic resin composite material in the present embodiment is assumed to be used as the vehicle component. Examples of such vehicle components include panel members and main skeleton members such as side sills, center pillars, and floor cross members.
However, the use of such a thermoplastic resin composite material is not limited to the above-mentioned vehicle components, for example, components of moving bodies other than vehicles such as ships and aircraft, as well as buildings, for example. , It can also be applied to constituent members such as various devices.

≪Manufacturing equipment for thermoplastic resin composite materials≫
Next, the apparatus for producing the thermoplastic resin composite material according to the present embodiment will be described.
FIG. 1 is a configuration explanatory view of the thermoplastic resin composite material manufacturing apparatus 10 according to the present embodiment. FIG. 2 is a partial cross-sectional view of the extruder 1 constituting the manufacturing apparatus 10 of FIG. In FIG. 2, the die 15 is shown by a virtual line (dotted line).

As shown in FIG. 1, the manufacturing apparatus 10 mainly includes an extruder 1 and a press machine 2.
The extruder 1 is a twin-screw extruder, and includes a cylinder 11 formed by connecting a plurality of cylinder blocks 19 and a screw 12 (see FIG. 2) described later, which is arranged inside the cylinder 11. There is.

At one end of the cylinder 11, a hopper 13 for supplying pellets of a thermoplastic resin is provided in the cylinder 11.
Further, a die 15 is arranged at the other end of the cylinder 11. The die 15 will be described in detail later.

An input port 14 for the reinforcing fiber 3 is provided at substantially the center of the cylinder 11 in the longitudinal direction. The input port 14 in the present embodiment is assumed to be supplied with so-called roving-shaped reinforcing fibers 3 made of fiber bundles. However, the charging port 14 may be one in which the reinforcing fibers 3 previously cut to a predetermined length are charged.

Further, a gas vent 16 is provided between the hopper 13 in the cylinder 11 and the input port 14 of the reinforcing fiber 3.
In FIG. 1, reference numeral 18 is a driving unit of the screw 12 (see FIG. 2). The drive unit 18 includes a motor, a transmission, and the like (not shown).

As shown in FIG. 2, the extruder 1 has a screw 12 inside the cylinder 11 as described above. The screw 12 is rotated around an axis by a drive unit 18 (see FIG. 1) to transport the contents of the cylinder 11 from one end side to the other end side. That is, in the extruder 1 of the present embodiment, the upstream side is defined on one end side of the cylinder 11 in which the hopper 13 is arranged, and the downstream side is defined on the other end side of the cylinder 11 in which the die 15 is arranged.

The cylinder 11 has a resin feed section 11a, a transport section 11b, a kneading section 11c, and a rear transport section 11d from the upstream side to the downstream side. Each of the screw elements constituting the screw 12 is arranged in each of the resin feed unit 11a, the transport unit 11b, the kneading unit 11c, and the rear transport unit 11d.

In the extruder 1, the pellet-shaped thermoplastic resin charged from the hopper 13 is heated by the resin feed portion 11a to be melted and transported to the downstream side. In the extruder 1 of the present embodiment, it is assumed that the pellet-shaped thermoplastic resin is charged via the hopper 13, but the extruder 1 is not limited to this, and is pre-plasticized at the position of the hopper 13. It is also possible to further include an extruder (not shown) for charging the thermoplastic resin.

The transport section 11b is provided between the resin feed section 11a and the kneading section 11c. The transport unit 11b mixes the reinforcing fibers 3 (see FIG. 1) charged from the charging port 14 with the molten thermoplastic resin produced by the resin feed unit 11a, and transports them toward the kneading unit 11c.

The kneading portion 11c kneads the molten thermoplastic resin and the reinforcing fiber 3 (see FIG. 1). At this time, the reinforcing fiber 3 is promoted to defibrate and cut the roving. The cut reinforcing fibers 3 are uniformly dispersed in the molten thermoplastic resin.

The post-transport section 11d is provided so as to stably extrude the kneaded product of the reinforcing fiber 3 (see FIG. 1) and the molten thermoplastic resin toward the die 15.
Then, as shown in FIG. 1, this kneaded product is extruded from the die 15 as an extruded product 4. In FIG. 1, reference numeral 17 is a cutter that cuts the extruded product 4 extruded from the die 15 to a predetermined length.

As shown in FIG. 1, the press machine 2 supports the upper die 21a including the upper die 21a and the lower die 21b, the base 22 supporting the lower die 21b, and the upper die 21a above the lower die 21b. Mainly includes an elevating portion 23 for moving the upper die 21a up and down with respect to the lower die 21b.
In the mold 21, a cavity is formed inside the upper mold 21a and the lower mold 21b on which the upper mold 21a and the lower mold 21b are overlapped with each other in the vertical direction.
The upper mold 21a is pressed against the lower mold 21b on the base 22 by the elevating portion 23 with a predetermined pressure to mold-tighten, so that the molding material (extruded product 4) arranged in the cavity is press-molded.
In FIG. 1, the arrow indicating direction indicated by reference numeral 6 is the mold clamping direction of the extruded product 4.

Further, the manufacturing apparatus 10 of the present embodiment may include, although not shown, a heat insulating furnace, a transfer mechanism for the extruder 4, and the like, in addition to the extruder 1 and the press 2.
As the heat insulating furnace, a conveyor (not shown) that feeds the extruder 4 cut to a predetermined length by the cutter 17 in a direction away from the extrusion port of the extruder 1 and the extruder 4 that is fed by this conveyor to a predetermined temperature. An example is provided with a heater for retaining heat (not shown).
Examples of the transfer mechanism of the extruded product 4 include a material handling robot (not shown) that grips the extruded product 4 and arranges it in the mold 21 of the press machine 2.

Next, the die 15 of the extruder 1 will be described.
FIG. 3 is a front view (end view) of the die 15 including a cross section of the extruded product 4.
As shown in FIG. 3, the die 15 has an opening 15a into which the extrude 4 is extruded. The extruded product 4 has a cross-sectional shape that follows the shape of the opening 15a.
In the method for producing a thermoplastic resin composite material, which will be described later, the preformed body 5 (see FIG. 1) is formed by the extruded product 4 having a cross-sectional shape following the shape of the opening 15a. Then, the preformed body 5 is cut to a predetermined length by the cutter 17 (see FIG. 1) and supplied to the press machine 2 (see FIG. 1) as a molding material.

As shown in FIG. 3, the opening 15a of the die 15 has the first width W1 of the opening 15a corresponding to the mold clamping direction 6 of the extrusion 4 (the same as the direction marked with the reference numeral 6 in FIG. 1). It is non-uniform over the second width W2 of the opening 15a in the direction intersecting the width W1 (in the present embodiment, the direction orthogonal to each other).

Specifically, in the shape of the opening 15a of the die 15, the first width W1 at both ends in the extending direction of the second width W2 (the width direction of the second width W2) is the center in the width direction of the second width W2. It is bigger than the part. More specifically, the shape of the opening 15a of the die 15 is formed by an elongated rectangular portion 15b extending in the width direction at the center portion in the width direction of the second width W2 and both end portions in the width direction of the second width W2. It is formed of a pair of right-angled trapezoidal portions 15c having symmetrical shapes, which are arranged so that the hypotenuses face each other with the rectangular portion 15b interposed therebetween.

As a result, the shape of the opening 15a of the die 15 has the largest portion corresponding to the height of the first width W1 at the widthwise end of the second width W2, that is, the right-angled trapezoidal portion 15c. Further, the opening 15a is formed with a taper Ta in which the first width W1 increases from the center in the width direction to the end in the width direction of the second width W2 by the portion corresponding to the hypotenuse of the right-angled trapezoidal portion 15c.

The preformed body 5 formed by being extruded from the opening 15a of the die 15 has a cross-sectional shape that follows the shape of the opening 15a as described above. That is, the preformed body 5 has a rectangular portion 15b and a right-angled trapezoidal portion 15c following the shape of the opening 15a.

Further, the shape of the opening 15a of the die 15 is not limited to the one in which the first width W1 at each of both ends of the second width W2 in the width direction is larger than the first width W1 at the central portion. That is, the shape of the opening 15a of the die 15 may be such that the first width W1 at at least one end portion of both ends of the second width W2 in the width direction is larger than the first width W1 at the central portion.

≪Manufacturing method of thermoplastic resin composite material≫
As shown in FIG. 1, the manufacturing method of the present embodiment is a direct press molding method in which an extruder 4 (preformed body 5) from an extruder 1 is directly molded by a press machine 2.
Hereinafter, the method for manufacturing the thermoplastic resin composite material of the present embodiment will be described while explaining the operation of the thermoplastic resin composite material manufacturing apparatus 10 with reference to FIGS. 1 to 3.

In this manufacturing method, the thermoplastic resin is charged into the cylinder 11 via the hopper 13 and the reinforcing fibers 3 are supplied from the charging port 14 in the manufacturing apparatus 10 during steady operation after warming up.
Reinforcing fibers 3 are mixed in the thermoplastic resin heated and melted in the resin feed section 11a and transported toward the kneading section 11c in the transport section 11b. The molten thermoplastic resin and the reinforcing fiber 3 are kneaded in the kneading portion 11c. As a result, a kneaded product in which the reinforcing fibers 3 are uniformly dispersed is formed in the molten thermoplastic resin.

This kneaded product is extruded from the die 15 via the rear transport unit 11d. The extruded product 4 extruded from the opening 15a of the die 15 becomes a preformed body 5 having a cross-sectional shape that follows the shape of the opening 15a.
The opening 15a of the die 15 corresponds to the "opening having a predetermined shape" in the claims. Further, the step of extruding the kneaded material from the opening 15a of the die 15 to form the preformed body 5 having a cross-sectional shape following the shape of the opening 15a corresponds to the "preforming step" in the claims.

Next, in the manufacturing apparatus 10, the extruded product 4 (preformed body 5) cut to a predetermined length by the cutter 17 is placed in the mold 21 of the press machine 2 and molded. The preformed body 5 flows in the mold 21 and is cooled to become a molded product (thermoplastic resin composite material) having a predetermined shape.
The step of molding the preformed body 5 with a die 21 to form a molded product (thermoplastic resin composite material) corresponds to the "press molding step" in the claims.
Then, by removing the molded product (thermoplastic resin composite material) from the mold 21, a series of manufacturing methods of the thermoplastic resin composite material is completed.

≪Action effect≫
Next, the method for manufacturing the thermoplastic resin composite material and the action and effect of the manufacturing apparatus 10 according to the present embodiment will be described.
FIG. 4 is a graph showing the relationship between the temperature of the molding material from the start of molding in the mold 21 (see FIG. 1) to the time when the mold is removed and cooled to room temperature, and the specific volume of the molding material. In FIG. 4, the line segment indicated by a'-b'-c'is a line segment showing a relative change in temperature and specific volume of the molding material in which the molding start pressure in the mold 21 is relatively low. Is. The line segment represented by abc is a line segment showing a relative change in temperature and specific volume of the molding material in which the molding start pressure in the mold 21 is relatively high. Further, in the specific volume shown by the vertical axis of the graph of FIG. 4, the increasing direction represents the expansion of the molding material, and the decreasing direction represents the contraction of the molding material.

As shown in FIG. 4, each of the molding materials (pre-molded body 5 (see FIG. 1)) represented by the a'-b'-c' line segment and the ab-c line segment is a mold 21 (FIG. 1). After being supplied into the lower die 21b (see FIG. 1), the upper die 21a (see FIG. 1) descending toward the lower die 21b (see FIG. 1) comes into contact with the molding material to start press molding.
The temperature of the molding material at the start of molding in the mold 21 (see FIG. 1) is shown by "molding resin temperature" in FIG.

After the upper mold 21a comes into contact with the molding material arranged on the lower mold 21b, the molding material flows and spreads in the mold 21 as the upper mold 21a further descends and approaches the lower mold 21b. The molding material is cooled by the mold 21 to lower the temperature. At the same time, the molding material is molded in the mold 21 and the specific volume decreases with this temperature drop. Then, by crystallizing or solidifying in the mold 21, the specific volume of the molding material rapidly decreases. When the crystallization of the molding material is completed, the rate of decrease in specific volume becomes slow. After that, the specific volume of the molding material changes to room temperature at this slow decrease rate until it is cooled to room temperature, but when the temperature of the molding material reaches the mold temperature, it is demolded from the mold 21. To.
After demolding, the molding material is exposed to the outside air and allowed to cool to room temperature.

That is, as shown in FIG. 4, the shrinkage amount of the molding material is determined by the difference in the specific volume from the start of molding by the mold 21 (see FIG. 1) to the cooling to room temperature.
Therefore, the lower the temperature of the molding material at the start of molding and the higher the starting pressure of molding, the smaller the shrinkage amount of the molding material.

FIG. 5 to be referred to next is a schematic view for explaining the flow pattern of the preformed body 5 (molding material) by molding. FIG. 5 (a) shows the flow pattern of the embodiment of the present invention, and FIG. 5 (b) shows the flow pattern of the comparative example. Further, in FIGS. 5 (a) and 5 (b), the state of the preformed body 5 (molding material) before and during mold clamping is shown with a white arrow in between.

In FIGS. 5A and 5B, reference numeral A is a lower mold contact layer when the preformed body 5 (molding material) is arranged on the lower mold 21b. Reference numeral B is a lower inner layer adjacent to the lower contact layer A. Reference numeral C is a surface layer of the preformed body 5 (molding material). Reference numeral D is an upper inner layer adjacent to the surface layer C. Reference numeral E is a central layer between the lower inner layer B and the upper inner layer D.

First, the flow pattern in the preformed body 5 (molding material) of the comparative example will be described.
As shown in FIG. 5 (b), the shape of the preformed body 5 of the comparative example arranged on the lower mold 21b is assumed to be substantially flat (in FIG. 5 (b), before the mold is fastened. See figure).
In this comparative example, after the preformed body 5 is placed on the lower mold 21b, the magnitude relationship of the temperatures in the layers A, B, C, D, and E of the preformed body 5 immediately before the mold clamping is as follows. ing.
Lower contact layer A <Lower inner layer B <Surface layer C <Upper inner layer D <Central layer E
Further, the magnitude relationship of the viscosities of each layer A, B, C, D, and E of the preformed body 5 is as follows.
Lower contact layer A> Lower inner layer B> Surface layer C> Upper inner layer D >> Central layer E

Then, when the mold clamping by the upper mold 21a and the lower mold 21b is started on the preformed body 5 (see the figure at the time of mold clamping in FIG. 5 (b)), each layer A, B, C of the preformed body 5 Cooling of D and E is started in the following order.
Lower contact layer A> Lower inner layer B> Surface layer C> Upper inner layer D> Central layer E
As a result, the lower inner layer B flows so as to cover the lower mold contact layer A forming the solidified layer (skin layer) on the lower mold 21b.
Next, the surface layer C whose cooling is promoted by contacting with the upper mold 21a is solidified, and the upper inner layer D flows so as to cover the solidified layer.

Then, the central layer E having the latest cooling start timing and the lowest viscosity forms a spring flow (fountain flow) from between the lower inner layer B and the upper inner layer D in the direction indicated by the arrow of reference numeral 7. That is, the central layer E having a high temperature and a low pressure spreads preferentially between the upper mold 21a and the lower mold 21b.
As shown in FIG. 4, the high-temperature and low-pressure portions that spread between the upper mold 21a and the lower mold 21b due to the spring flow (fountain flow) of the central layer E have a large amount of shrinkage after cooling. .. That is, as shown in FIG. 5B, the portion expanded by the spring flow (fountain flow) of the central layer E forms the contraction amount increasing region Ct2.

Next, the flow pattern in the preformed body 5 (molding material) of the embodiment of the present invention will be described.
As shown in FIG. 5A, the shape of the preformed body 5 of the comparative example arranged on the lower mold 21b is assumed to be the same as that shown in FIG. 3 (in FIG. 5A). , See the figure before mold clamping).
That is, the preformed body 5 of this embodiment has a rectangular portion 15b and a pair of right-angled trapezoidal portions 15c formed so as to sandwich the rectangular portion 15b.
In the preformed body 5 of the example, unlike the preformed body 5 of the comparative example, the surface layer C and the upper inner layer D are divided into two corresponding to the pair of right-angled trapezoidal portions 15c.
The magnitude relationship between the temperature and viscosity of each of the layers A, B, C, D, and E of the preformed body 5 and the timing of cooling start of each layer A, B, C, D, and E are determined in the above comparative example. Things are similar.

Then, when the mold clamping by the upper mold 21a and the lower mold 21b is started on the preformed body 5 (see the figure at the time of mold clamping in FIG. 5A), the solidified layer (skin layer) is formed on the lower mold 21b. The lower inner layer B flows so as to cover the lower type contact layer A to be formed.

Next, each of the bisected surface layers C is solidified by coming into contact with the upper mold 21a, and the upper inner layer D flows so as to cover each solidified layer of the bisected surface layer C. That is, the upper inner layer D in the example has a longer flow distance along the upper mold 21a than the upper inner layer D in the comparative example.
Therefore, the contraction amount increase region Ct1 formed by the spring flow 7 from between the lower inner layer B and the upper inner layer D is narrower than the contraction amount increase region Ct2 of the comparative example (Ct1 <Ct2).
Therefore, the shrinkage of the molded product (thermoplastic resin composite material) due to the spring flow 7 in the examples is suppressed as compared with the comparative example.

In the method and apparatus 10 for manufacturing a thermoplastic resin composite material according to the present embodiment, an extruded product 4 (preformed body 5) obtained by extruding a kneaded product of a thermoplastic resin and reinforcing fibers from an opening 15a having a predetermined shape is directly used. The thermoplastic resin composite material is manufactured by molding in the mold 21.

According to such a manufacturing method and the manufacturing apparatus 10, it is possible to put the preformed body 5 into the mold 21 while maintaining the temperature at a high temperature. Further, the kneaded product constituting the preformed body 5 is soft at a high temperature, and the preformed body 5 is easily formed by the extruded product 4 formed following the shape of the opening 15a. Therefore, according to this manufacturing method, it is not necessary to separately arrange equipment for molding the kneaded product into the preformed body 5. Therefore, according to the present embodiment, it is possible to reduce the size of the manufacturing equipment for the thermoplastic resin composite material.

Further, according to the method for manufacturing the thermoplastic resin composite material and the manufacturing apparatus 10 according to the present embodiment, the preformed body 5 discharged from the extruder 1 can be directly put into the mold 21. Therefore, the mold 21 The time required for charging into the inside does not increase, and the preformed body 5 can be easily molded.

Further, in the manufacturing method and manufacturing apparatus 10 of the present embodiment, the shape of the opening 15a has the largest first width W1 at at least one end in the extending direction of the second width W2.

Generally, when the molding material is directly press-molded by a press machine, the outer side of the molding material has a larger contact area with the die, so that it tends to cool rapidly. When the molding material cools rapidly (when the temperature range of the molding material decreases is large), the amount of shrinkage increases. Therefore, a difference in the amount of shrinkage occurs between the central portion and the outer portion of the molded material, and the molded product is deformed such as warped.

On the other hand, in the present embodiment, the thick portion of the preformed body 5 comes into contact with the mold 21 before the thin portion when the mold 21 is clamped. Then, heat is drawn from the portion in contact with the mold 21, and curing (solidification) starts first. That is, as described above, the spring flow (fountain flow) is weakened, so that the shrinkage deformation becomes small. Therefore, even if the molded product (thermoplastic resin composite material) is taken out from the mold 21 after molding, deformation of the molded product (thermoplastic resin composite material) is suppressed.

Further, in the present embodiment, since a large amount of the molding material is arranged at the widthwise end portion of the second width W2, the flow of the molding material to the corner portion in the mold 21 is promoted. Thereby, according to the present embodiment, a molded product (thermoplastic resin composite material) without sink marks can be obtained.

In the manufacturing method and manufacturing apparatus 10 of the present embodiment, a taper Ta is formed from the central portion side to the end portion side of the second width W2 in the opening 15a. Since the preformed body 5 (molding material) is formed following the shape of the opening 15a, a similar taper Ta is formed. Incidentally, the first width W1 coincides with the mold clamping direction 6 by the mold 21.

According to this embodiment, when the preformed body 5 (molding material) is molded by the mold 21, the end portion of the preformed body 5 (molding material) having a thick first width W1 is tapered. Can easily flow outward in the width direction of the second width W2. Therefore, the flow of the molding material to the corners in the mold 21 is promoted. Thereby, according to the present embodiment, a molded product (thermoplastic resin composite material) without sink marks can be obtained.

Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made without departing from the spirit of the present invention.
In the above-described embodiment, the preformed body 5 having a rectangular portion 15b and a pair of right-angled trapezoidal portions 15c formed so as to sandwich the rectangular portion 15b has been described, but the preformed body 5 is limited to this. It is not something that is done.

6 (a) and 6 (b) are structural explanatory views of the preformed body 5 according to the modified example.
As shown in FIG. 6A, the preformed body 5 is larger than the rectangular portion 15b in the central portion and larger than the first width W1 instead of the right-angled trapezoidal portion 15c (see FIG. 3) in the embodiment. It has a rectangular portion 15d having a width W1.

Further, as shown in FIG. 6B, the preformed body 5 may be configured to have a vertical wall portion 15e that integrally connects the pair of rectangular portions 15d to each other and the rectangular portions 15c.
As shown in FIG. 6A, such a preformed body 5 can be formed by forming the die 15 with a fixed die 150 and a movable die 151 that can move forward and backward with respect to the fixed die 150.
That is, when the vertical wall portion 15e is molded, the lower edge 8a of the movable die 151 is moved to the underline 8b indicated by the alternate long and short dash line, and when the rectangular portions 15c and 15d are molded, the lower edge 8a of the movable die 151 is moved to FIG. 6 (a). ), The preformed body 5 shown in FIG. 6B can be obtained.
It is also possible to form the preformed body 5 having the vertical wall portion 15e by laminating the separately heated resin on the resin molded by the fixed die 150 before arranging the resin in the mold.

Next, an example in which the action and effect of the present invention have been verified will be described.
FIG. 7A is a perspective view of the preformed body 5 (molding material) used in the examples. FIG. 7B is a perspective view of the preformed body 50 (molding material) used in the comparative example.
As shown in FIG. 7A, the preformed body 5 of the embodiment includes a rectangular portion 15b and a right-angled trapezoidal portion 15c, similarly to the preformed body 5 (see FIG. 3) according to the embodiment. There is.
It is assumed that the preformed body 5 contains 6 nylon as a thermoplastic resin so that the volume fraction (Vf) of carbon fiber as a reinforcing fiber is 30%.

The extrusion width W of the preformed body 5 is 180 mm, and the extrusion length L is 700 mm. Although not shown, the maximum height t1 of the preformed body 5 is 45 mm, and the height t2 of the rectangular portion 15b of the preformed body 5 is 6 mm. Further, the length W'1 of the upper base of the right-angled trapezoidal portion 15c of the preformed body 5 is 15 mm, and the length W'3 of the lower base is 42 mm.
Then, in the measurement of the “flow distance of the molding material” described later, in FIG. 7A, a sample S having a quarter size of the preformed body 5 partitioned by the dotted line was set.

As shown in FIG. 7B, the preformed body 50 of the comparative example is a flat plate body (rectangular parallelepiped) having substantially the same volume as the preformed body 5 of the embodiment. Similar to the preformed body 5, the preformed body 50 is assumed to include a volume fraction (Vf) of carbon fiber as a reinforcing fiber of 30% with respect to 6 nylon as a thermoplastic resin. ing.
Incidentally, the extrusion width W of the preformed body 50 is 180 mm, the extrusion length L is 700 mm, and the height t'is 17.8 mm.
Then, in the measurement of the “flow distance of the molding material” described later, in FIG. 7 (b), a sample S having a size of 1/4 of the preformed body 50 partitioned by the dotted line was set.

FIG. 8A is a plan view of the preformed body 5 (molding material) used in the examples.
Then, in the measurement of the "temperature distribution of the molding material", the "pressure distribution of the molding material" and the "warp amount distribution of the molded product" described later, in FIG. One size of the sample S was set as the sample S.

FIG. 8B is a plan view of the preformed body 50 (molding material) used in the comparative example.
Then, in the measurement of the "temperature distribution of the molding material", the "pressure distribution of the molding material" and the "warp amount distribution of the molded product" described later, in FIG. One size of the sample S was set as the sample S.
The "axis of symmetry" shown in FIGS. 8 (a) and 8 (b) is an axis extending in a direction orthogonal to the XY plane (orthogonal direction on the paper surface of FIG. 8) in the central portion of the XY plane of the preformed bodies 5, 50. (Hereinafter, the same applies to FIGS. 9 to 15).

In this embodiment, (1) the flow distance of the molding material (sample S) in the mold, (2) the temperature distribution of the molding material (sample S) after the mold clamping and filling, and (3) the molding after the mold clamping and filling. The pressure distribution of the material (sample S) and (4) the warp amount distribution of the molded product after demolding were measured and tested by CAE (computer aided engineering).
The molding conditions for the preformed bodies 5, 50 were set as follows.
Extruded temperature: 265 ° C
Mold temperature: 180 ° C
Heat transfer coefficient of extruded product and air (25 ° C): 10 W / m ² ° C
Heat transfer coefficient between extruded product and mold: 1000 W / m ² ° C
Initial mold opening: 50 mm
Press speed when measuring flow distance: 3 mm / s
Pressing force when measuring flow distance: 200t
Press speed when measuring the amount of warpage: 50 mm / s
Pressing force when measuring the amount of warpage: 700t

(1) The measurement results of the flow distance of the molding material in the mold are shown in FIGS. 9 to 12.
9 to 12 show the flow distances of the preformed body 5 of the example (sample S (see FIG. 7A)) and the preformed body 50 of the comparative example after a predetermined time has elapsed from the start of mold clamping. It is a comparative figure which shows the measurement result of 1st stage to 4th stage).
FIG. 9 is a flow distance comparison diagram after 1.60 [sec] has elapsed from the start of mold clamping. FIG. 10 is a flow distance comparison diagram after 10.70 [sec] has elapsed in the examples and 10.80 [sec] has elapsed in the comparative example from the start of mold clamping. FIG. 11 is a flow distance comparison diagram after 12.00 [sec] has elapsed from the start of mold clamping. FIG. 12 is a flow distance comparison diagram after 16.01 [sec] has elapsed in the examples and 16.00 [sec] has elapsed in the comparative example from the start of mold clamping.
Further, the flow distance comparison of the preformed bodies 5, 50 is performed based on the flow tip of the preformed body 50 of the comparative example.
In FIGS. 9 to 12, the temperature distributions of the preformed bodies 5 and 50 according to the elapsed time are represented by high temperature (white), medium temperature (shaded), and low temperature (blackened).

As shown in FIGS. 9 to 12, the flow distance of the preformed body 5 of the example in the mold is longer in all of the first to fourth stages as compared with the preformed body 50 of the comparative example. Was confirmed.
Further, as shown in FIG. 12, it was confirmed that the temperature of the preformed body 5 of the example spread in the mold was lower than that of the preformed body 50 of the comparative example, and the shrinkage amount was small.

(2) The measurement results of the temperature distribution of the molding material (sample S) after mold clamping and filling are shown in FIGS. 13 (a) and 13 (b).
FIG. 13A is a plan view showing the temperature distribution in the preformed body 5 of the example after mold clamping and filling. FIG. 13B is a plan view showing the temperature distribution in the preformed body 50 of the comparative example after mold clamping and filling.
The temperature distribution is represented by a shaded pattern representing the magnitude relationship of T1 <T2 <T3 <T4 <T4 <T5.

As shown in FIGS. 13A and 13B, unlike the preformed body 50 of the comparative example, the preformed body 5 of the example has a T1 region having a low temperature appearing in a region near the axis of symmetry.
As a result, it was confirmed that the preformed body 5 of the example had a smaller shrinkage amount than the preformed body 50 of the comparative example.

(3) The measurement results of the pressure distribution of the molding material (sample S) after mold clamping and filling are shown in FIGS. 14 (a) and 14 (b).
FIG. 14A is a plan view showing the pressure distribution in the preformed body 5 of the example after mold clamping and filling. FIG. 14B is a plan view showing the pressure distribution in the preformed body 50 of the comparative example after mold clamping and filling.
The pressure distribution is represented by a shaded pattern representing the magnitude relationship of P1 <P2 <P3 <P4 <P5.

As shown in FIGS. 14 (a) and 14 (b), the preformed body 5 of the example has a region closer to the axis of symmetry and a wider P5 region with high pressure than the preformed body 50 of the comparative example. confirmed.
As a result, it was confirmed that the preformed body 5 of the example had a smaller shrinkage amount than the preformed body 50 of the comparative example.

(4) The measurement results of the warp amount distribution of the molded product (thermoplastic resin composite material) after demolding are shown in FIGS. 15 (a) and 15 (b).
FIG. 15A is a plan view showing the warp amount distribution of the molded product (thermoplastic resin composite material) of the example after demolding. FIG. 15B is a plan view showing the warp amount distribution of the molded product (thermoplastic resin composite material) of the comparative example after demolding.
The warp amount distribution is represented by a shading that represents the magnitude relationship of Wp1 <Wp2 <Wp3 <Wp4 <Wp5.

As shown in FIGS. 15A and 15B, the molded product (thermoplastic resin composite material) of the example is different from the molded product (thermoplastic resin composite material) of the comparative example, and Wp5 has the largest amount of warpage. It was confirmed that the Wp4 region, which has no region and has a relatively large amount of warpage, is also small. It was also confirmed that the molded product (thermoplastic resin composite material) of the example had a wide Wp1 region and Wp2 region in which the amount of warpage was relatively small.

1 Extruder 2 Press machine 3 Reinforced fiber 4 Extruded product 5 Preformed body 6 Mold tightening direction 7 Outflow flow 10 Manufacturing equipment 11 Cylinder 11a Resin feed part 11b Transport part 11c Kneading part 11d Post-transport part 12 Screw 15 Die 15a Die Opening 21 Mold 21a Upper mold 21b Lower mold W1 First width of opening W2 Second width of opening

Claims (3)

It is a method for manufacturing a thermoplastic resin composite material in which reinforcing fibers are dispersed in a thermoplastic resin.
A preforming step of kneading the thermoplastic resin and the reinforcing fiber under heating and extruding the kneaded material through an opening having a predetermined shape to form a preformed body having a cross-sectional shape that follows the shape of the opening.
It has a press molding step of molding the preformed body in a mold and molding the thermoplastic resin composite material having a predetermined shape.
The first width of the opening corresponding to the mold clamping direction of the preformed body is non-uniform over the second width of the opening in the direction intersecting the first width .
The shape of the opening is such that at least one end in the extending direction of the second width has a larger first width than the central portion in the extending direction of the second width, and the first width is from the central portion side. It is formed in a tapered shape in which the first width increases toward the larger part side.
A method for producing a thermoplastic resin composite material , wherein the opening has a rectangular portion as the central portion . In the method for producing a thermoplastic resin composite material according to claim 1,
A method for producing a thermoplastic resin composite material, wherein the shape of the opening has the largest first width at at least one end in the extending direction of the second width. An extruder that kneads and extrudes thermoplastic resin and reinforcing fibers under heating,
A device for producing a thermoplastic resin composite material, comprising: a press machine for molding an extruded product extruded from the extruder to form a thermoplastic resin composite material.
The opening of the die of the extruder from which the extruder is extruded extends over the second width of the opening in a direction in which the first width of the opening corresponding to the mold clamping direction of the extruder intersects the first width. Is uneven ,
The shape of the opening is such that at least one end in the extending direction of the second width has a larger first width than the central portion in the extending direction of the second width, and the first width is from the central portion side. It is formed in a tapered shape in which the first width increases toward the larger part side.
An apparatus for producing a thermoplastic resin composite material , wherein the opening has a rectangular portion as the central portion .

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