JP7579696B2 - Impregnation Equipment - Google Patents

Description

The present invention relates to an impregnation device used in producing long fiber reinforced thermoplastic resin.

Long-fiber reinforced thermoplastic resin is known as a type of thermoplastic resin reinforced with fibers. This long-fiber reinforced thermoplastic resin is a composite material made of fibers and thermoplastic resin, which combines the properties of thermoplastic resin with the strength and heat resistance of fibers, and is used in a variety of structural and heat-resistant components.

Conventionally, impregnation dies have been used to manufacture such long fiber reinforced thermoplastic resins (see, for example, Patent Document 1). There are various types of impregnation dies, but for example, as shown in FIG. 5, in an impregnation die 58 consisting of an upper die 58a and a lower die 58b, molten thermoplastic resin 60 is impregnated into a fiber bundle 62 in a gap 58c between the upper die 58a and the lower die 58b to produce a continuous fiber reinforced strand 64.

Here, the narrower the gap 58c between the upper die 58a and the lower die 58b, the easier it is for the fiber bundle 62 to spread and for the fiber bundle 62 to be impregnated into the thermoplastic resin 60. However, narrowing the gap 58c increases the risk of the fiber bundle 62 breaking.
For this reason, currently, a measure against such a risk is taken in which a thin iron plate is inserted into gap 58c to adjust the gap.

JP 2007-175959 A

However, in the above-mentioned impregnation die 58, the upper die 58a and the lower die 58b are usually fastened together with bolts (not shown), which creates the problem that it is not possible to constantly adjust the size of the gap 58c while checking the state of the continuous fiber-reinforced strand 64.

For this reason, for example, when a large amount of fuzz was generated on the fiber bundle 62 moving through the gap 58c, it was necessary to stop the operation of the long fiber reinforced thermoplastic resin manufacturing apparatus (not shown) each time, remove the bolts, and then remove the fuzz.
An object of the present invention is to provide an impregnation device capable of constantly adjusting the gap between the upper and lower dies.

The impregnation device of the present invention comprises:
An impregnation device for producing a continuous fiber reinforced strand by impregnating a fiber bundle with a molten thermoplastic resin when producing a long fiber reinforced thermoplastic resin,
an impregnation die having an upper mold and a lower mold, the gap through which the fiber bundle impregnated with the thermoplastic resin passes being formed between the upper mold and the lower mold;
The mold is characterized in that it is provided with a gap adjustment unit that adjusts the size of the gap by raising and lowering at least one of the upper mold and the lower mold.
This allows the operator to constantly adjust the gap between the upper and lower dies while watching the process of creating the continuous fiber reinforced strand in the impregnation die.

The impregnation apparatus of the present invention further comprises:
a ball screw having a male screw portion formed thereon and rotated by driving the gap adjustment portion ;
an upper support frame fixed to the upper mold and a lower support frame fixed to the lower mold,
At least one of the upper support frame and the lower support frame is formed with a female screw portion that screws into the male screw portion,
As the ball screw rotates, one or both of the upper support frame and the lower support frame having the female threaded portion rise and fall through the screwing of the male threaded portion and the female threaded portion , and at least one of the upper mold and the lower mold rise and fall accordingly.
In this way, by utilizing the screwing of the male screw portion and the female screw portion, the gap width can be continuously adjusted.

The impregnation apparatus of the present invention further comprises:
A camera for capturing an image of the gap;
A determination unit is provided that determines whether or not a predetermined amount of fluff is generated based on the image captured by the camera,
The gap adjusting section is characterized in that it opens the gap when the determining section determines that a predetermined amount or more of fluff has been generated.
This allows the gap between the upper and lower dies to be constantly adjusted with almost no manual intervention.

The impregnation apparatus of the present invention further comprises:
The gap adjustment unit is a servo motor,
The ball screw is arranged coaxially with a motor shaft of the gap adjustment unit.
This allows the structure of the impregnation device to be simplified.

The present invention provides an impregnation device that can constantly adjust the gap between the upper and lower dies.

FIG. 1 is a schematic diagram of a long fiber reinforced thermoplastic resin production apparatus using an impregnation die according to an embodiment. FIG. 1 is a diagram showing an outline of an impregnation device according to an embodiment. FIG. 2 is a block diagram showing a configuration of an impregnation device according to an embodiment. 4 is a flowchart showing a process for adjusting the gap width of an impregnation die by the impregnation device according to the embodiment. FIG. 1 is a diagram showing an outline of a conventional impregnation die.

The following describes an embodiment of the present invention with reference to the drawings. Figure 1 is a schematic diagram of a long fiber reinforced thermoplastic resin manufacturing apparatus equipped with an impregnation device according to an embodiment. As shown in Figure 1, the long fiber reinforced thermoplastic resin manufacturing apparatus 2 is equipped with a payout machine 4, a fiber opening bar 6, an extruder 8, an impregnation device 9, a shaping die 12, a water tank 14, a forming roll 16, a take-up machine 18, and a cutter section 20.

Here, the unwinding machine 4 stores a plurality of carbon fiber rovings 4a around which fiber bundles 32 are wound. The unwinding machine 4 also includes a unwinding roll 4b for unwinding the fiber bundles 32 from the carbon fiber rovings 4a. The fiber bundles 32 are made of, for example, glass fiber or carbon fiber.

The spreading bar 6 is a roll bar for carrying out a spreading process of spreading the fiber bundle 32 unwound from the unwinding roll 4b.
The extruder 8 is a device that supplies molten thermoplastic resin to an impregnation die 10 included in an impregnation device 9 according to the present invention, and the impregnation die 10 is a device that performs an impregnation step of impregnating the opened fiber bundle 32 with the molten thermoplastic resin. In this impregnation step, a continuous fiber-reinforced strand 34 is produced. Note that, for example, polypropylene, polyamide, etc. are used as the thermoplastic resin.

The shaping die 12 is a device for reducing the diameter of the continuous fiber-reinforced strand 34, and is attached to the side of the impregnation die 10 from which the continuous fiber-reinforced strand 34 is discharged.
The water tank 14 is a device for immersing the continuous fiber-reinforced strand 34, the diameter of which has been reduced by the shaping die 12, in a liquid such as water to cool it.

The forming roll 16 is a roll bar for forming the outer diameter shape of the continuous fiber-reinforced strand 34 cooled in the water tank 14 .
The take-up machine 18 is a roll for performing a take-up process of taking up the continuous fiber-reinforced strand 34 .

The cutter section 20 is a device for cutting the continuous fiber reinforced strand 34 taken up by the take-up machine 18 to a predetermined length. By cutting the continuous fiber reinforced strand 34 with this cutter section 20, a long fiber reinforced thermoplastic resin 38 is produced.

Next, we will explain the impregnation device 9 that constitutes the main part of the long fiber reinforced thermoplastic resin manufacturing apparatus 2 in the present invention. Figure 2 is a diagram showing an overview of the impregnation device 9. As shown in Figure 2, the impregnation device 9 includes an impregnation die 10, a support frame 42, a ball screw 44, a servo motor 46, and a controller 48 (see Figure 3).

Here, the impregnation die 10 consists of an upper die 10a and a lower die 10b, and a gap 10c is formed between the upper die 10a and the lower die 10b through which the fiber bundle 32 (see Figure 1) impregnated with the thermoplastic resin passes.

The support frame 42 is a member that supports the impregnation die 10 from above and below, and has an upper support frame 42a fixed to the upper die 10a, and a lower support frame 42b fixed to the lower die 10b. The upper support frame 42a has a screw through hole 43 formed therein with a female threaded portion 43a that screws into the male threaded portion 44a of the ball screw 44. The lower support frame 42b has a through hole 45 through which the non-threaded portion 44b of the ball screw 44, which does not have the male threaded portion 44a, passes.

The ball screw 44 is a rod-shaped part that is fixed at its lower end coaxially with the motor shaft (not shown) of the servo motor 46 and stands on the servo motor 46, and passes through the screw through hole 43 and the through hole 45. The upper half of the ball screw 44 is formed with a male threaded portion 44a that screws into the female threaded portion 43a, and the lower half is formed with a non-threaded portion 44b that does not have a thread that passes through the through hole 45. Therefore, by rotating the ball screw 44, the upper support frame 42a can be raised and lowered.

The servo motor 46 is located below the lower support frame 42b and functions as a gap adjustment unit that adjusts the gap 10c. Specifically, as shown in the block diagram of FIG. 3, the control unit 46a is provided to comprehensively control each unit. The control unit 46a is provided with a drive unit 46b that rotates the ball screw 44, a camera 46c that captures the state of the gap 10c, a memory unit 46d that stores image data of the captured image, a gap memory unit 46e that stores the interval (hereinafter referred to as the pitch) for widening the gap 10c, and a communication unit 46f that transmits and receives data to and from the controller 48 by wire or wirelessly. The control unit 46a also functions as a judgment unit that judges whether or not a predetermined amount of fluff is generated in the fiber bundle 32 moving through the gap 10c.

The controller 48 is a part that an operator operates to adjust the gap 10c, and may be an independent operating device, or a terminal device such as a personal computer may be used as the controller 48.

Next, the procedure for the first method of adjusting the spacing of the gap 10c using the impregnation device 9 of the present invention will be described. Note that, here, an example will be described in which a predetermined amount or more of fuzz has been generated on the fiber bundle 32 moving through the gap 10c. First, while the long fiber reinforced thermoplastic resin manufacturing apparatus 2 is in operation, the operator visually monitors the state in which the continuous fiber reinforced strand 34 is produced by the impregnation die 10. Here, for example, if the operator recognizes that a predetermined amount or more of fuzz has been generated on the fiber bundle 32 moving through the gap 10c, he or she operates, for example, an open button (not shown) on the controller 48 to open the gap 10c.

When the open button is operated, a command signal to open the gap 10c is sent from the controller 48, received by the communication unit 46f of the servo motor 46, and detected by the control unit 46a. When the control unit 46a detects the command signal, it rotates the motor shaft in the direction to open the gap 10c via the drive unit 46b. This rotates the ball screw 44, and the upper support frame 42a, in which the female threaded portion 43a that screws into the male threaded portion 44a of the ball screw 44 is formed inside the screw through hole 43, rises, and the upper mold 10a fixed to the upper support frame 42a rises accordingly, widening the gap 10c.

After that, when the operator confirms that the fiber bundle 32 moving through the gap 10c is no longer generating a predetermined amount of fuzz or more, he operates a stop button (not shown). When the stop button is operated, a command signal to stop opening the gap 10c is sent from the controller 48, and is detected by the control unit 46a via the communication unit 46f of the servo motor 46. When the control unit 46a detects the command signal, the drive unit 46b stops the rotation of the motor shaft, and the rotation of the ball screw 44 stops. This maintains the gap 10c in an appropriate widened state, and the impregnation die 10 continues to produce the continuous fiber-reinforced strand 34 without generating a lot of fuzz. The widened gap 10c has a width of approximately 0.1 mm to 10 mm.

Next, the procedure for the second method of adjusting the spacing of the gap 10c using the impregnation device 9 of the present invention will be described. First, the long fiber reinforced thermoplastic resin manufacturing device 2 is operated, and after a certain period of time has elapsed, the control unit 46a starts to capture images of the process in which the continuous fiber reinforced strand 34 is produced in the impregnation die 10 using the camera 46c (step S1). The images are captured, for example, by taking a video or continuous still images.

After the image capture starts, the control unit 46a reads out the image data captured by the camera 46c from the storage unit 46d and determines whether or not a predetermined amount of fluff has been generated on the fiber bundle 32 moving through the gap 10c (step S2). The determination is made, for example, by detecting a state in which a predetermined amount of fluff has been generated on the fiber bundle 32 from an image based on the image data by pattern matching or the like.

If the fluff does not occur in a predetermined amount or more (step S2: No), the judgment operation of step S2 is repeated. On the other hand, if the fluff occurs in a predetermined amount or more (step S2: Yes), the control unit 46a rotates the motor shaft via the drive unit 46b in a direction to open the gap 10c (step S3). This rotates the ball screw 44 and raises the upper die 10a, widening the gap 10c. Here, the pitch for widening the gap 10c is preset in the gap memory unit 46e, for example, 0.05 mm, and the setting of the interval of the gap 10c can be changed as appropriate. Note that the pitch is preferably 0.02 mm or more and 0.10 mm or less.

Next, the control unit 46a uses the most recently captured image data to determine whether or not the fiber bundle 32 moving through the gap 10c has no more than a predetermined amount of fuzz (step S4). If the fiber bundle 32 moving through the gap 10c still has more than a predetermined amount of fuzz (step S4: No), the control unit 46a further widens the gap 10c (step S3) and repeats the determination (step S4).

On the other hand, if the fiber bundle 32 moving through the gap 10c no longer generates a predetermined amount of fuzz (step S4: Yes), the control unit 46a stops the rotation of the motor shaft by the drive unit 46b, and stops the rotation of the ball screw 44 (step S5). This maintains the gap 10c in an appropriate widened state, and the impregnation die 10 continues to produce a continuous fiber-reinforced strand 34 without generating a predetermined amount of fuzz on the fiber bundle 32 moving through the gap 10c.

The impregnation device 9 of this embodiment allows the width of the gap 10c between the upper die 10a and the lower die 10b to be constantly adjusted while observing how the continuous fiber-reinforced strand 34 is being produced in the impregnation die 10. This makes it easy to prevent excessive fuzz from being generated in the fiber bundle 32 due to the narrow gap 10c of the impregnation die 10.

This makes it possible to significantly reduce the amount of work required in the conventional technology to stop the operation of the long fiber reinforced thermoplastic resin manufacturing device 2 every time a large amount of fuzz is generated in the fiber bundle 32, remove the bolts, open the impregnation die 10, and then remove the fuzz.

Furthermore, by utilizing the screw engagement between the male screw portion 44a and the female screw portion 43a, the width of the gap 10c can be continuously adjusted.
Furthermore, even if a large amount of fluff occurs, the gap 10c can be opened immediately, so that fluff generation can be suppressed without putting a strain on the fiber bundle 32.

Furthermore, in conventional gap adjustment using an iron plate, the gap 58c (see FIG. 5) could only be adjusted to intervals of about 0.1 mm, for example. However, with the impregnation device 9 according to the embodiment, the gap 10c can be finely adjusted to the desired interval, allowing for more precise adjustment of the gap 10c.

In the above embodiment, the case where the gap 10c is adjusted by raising and lowering the upper mold 10a is illustrated, but the adjustment of the gap 10c is not necessarily limited to this method. For example, the gap 10c may be adjusted by raising and lowering the lower mold 10b.

In this case, a male threaded portion 44a is formed in the lower half of the ball screw 44, and a non-threaded portion 44b is formed in the upper half. A female threaded portion 43a that screws into the male threaded portion 44a of the ball screw 44 is provided in the lower support frame 42b, and the upper support frame 42a is rotatably fixed to the ball screw 44.

Alternatively, the gap 10c may be adjusted by raising and lowering both the upper die 10a and the lower die 10b. In this case, the male thread portion 44a is provided widely in the height direction of the ball screw 44, and the female thread portion 43a is provided on both the upper support frame 42a and the lower support frame 42b. However, the screwing directions of the upper support frame 42a and the lower support frame 42b are opposite.

In the above embodiment, in the first method, the opening and closing of the gap 10c is adjusted by operating the open button and close button on the controller 48, but a dial may be used instead of the open button and close button. In this case, for example, the gap 10c is continuously opened while the dial is operated in the forward direction, and the gap 10c is continuously closed while the dial is operated in the reverse direction. This allows for even finer adjustment of the gap.

In the above-described embodiment, the second method may store a plurality of candidate pitches in the gap memory unit 46e. A selection unit may be provided that selects a desired pitch from the plurality of candidates. The selection unit may be an independent part, but for example, the controller 48 may be used as the selection unit, and the desired pitch may be specified from the controller 48.

In addition, in the above-described embodiment, the first method may be used complementarily with the second method. That is, the distance of the gap 10c adjusted by the second method may be readjusted using an open button, a close button, a dial, or the like.

In the second method of the above embodiment, the pitch is set in the gap memory unit 46e, and the gap 10c is adjusted in increments of 0.05 mm, for example. However, as in the first method, the gap 10c may be adjusted continuously. This allows the gap 10c to be adjusted even more finely. In this case, steps S2 to S4 are performed while widening the gap 10c.

In addition, in the above embodiment, a case is illustrated in which the determination of whether or not a predetermined amount of fluff has occurred in the fiber bundle 32 is performed by pattern matching, but the determination does not necessarily have to be by pattern matching. In other words, other existing technologies may be used as long as it is possible to detect that a predetermined amount of fluff has occurred.

In the above-described embodiment, the gap adjustment unit does not necessarily have to be the servo motor 46 as long as it is a motor capable of adjusting the gap to a desired interval.
In the above embodiment, the impregnation device 9 is used to produce a long fiber reinforced thermoplastic resin, but the impregnation device 9 may be used in an apparatus for producing a long fiber reinforced resin other than the long fiber reinforced thermoplastic resin production apparatus 2. For example, the impregnation device 9 may be used when the fiber bundle 32 is made into a composite material with a thermosetting resin.

Furthermore, the impregnation device 9 can be used not only to manufacture long fiber reinforced resin, but also to manufacture other products that require fiber spreading. For example, it can be used to manufacture UD tapes, sheet molding compounds (SMC), prepregs, and fiber woven fabrics. Compared to manufacturing these products, when manufacturing long fiber reinforced thermoplastic resin, the fiber bundles 32 move faster and fluff is more likely to occur. For this reason, from the perspective of suppressing fluff, the impregnation device 9 according to the embodiment is ideal for manufacturing long fiber reinforced thermoplastic resin.

2 Long fiber reinforced thermoplastic resin manufacturing apparatus 4 Unwinder 4a Carbon fiber roving 4b Unwinding roll 6 Fiber opening bar 8 Extruder 9 Impregnation device 10 Impregnation die 10a Upper die 10b Lower die 10c Gap 12 Shaping die 14 Water tank 16 Forming roll 18 Take-up machine 20 Cutter section 32 Fiber bundle 34 Continuous fiber reinforced strand 38 Long fiber reinforced thermoplastic resin 42 Support frame 42a Upper support frame 42b Lower support frame 43 Screw through hole 43a Female threaded portion 44 Ball screw 44a Male threaded portion 44b Non-threaded portion 45 Through hole 46 Servo motor 46a Control unit 46b Drive unit 46c Camera 46d Memory unit 46e Gap memory unit 46f Communication unit 48 Controller 58 Impregnation die 58a Upper die 58b Lower die 58c Gap 60 Thermoplastic resin 62 Fiber bundle 64: Continuous fiber reinforced strand

Claims (4)

An impregnation device for producing a continuous fiber reinforced strand by impregnating a fiber bundle with a molten thermoplastic resin when producing a long fiber reinforced thermoplastic resin,
an impregnation die having an upper mold and a lower mold, the gap through which the fiber bundle impregnated with the thermoplastic resin passes being formed between the upper mold and the lower mold;
and a gap adjustment unit that adjusts the size of the gap by raising and lowering at least one of the upper mold and the lower mold. a ball screw having a male screw portion formed thereon and rotated by driving the gap adjustment portion ;
an upper support frame fixed to the upper mold and a lower support frame fixed to the lower mold,
At least one of the upper support frame and the lower support frame is formed with a female screw portion that screws into the male screw portion,
The impregnation device according to claim 1, characterized in that, as the ball screw rotates , one or both of the upper support frame and the lower support frame having the female threaded portion rise and fall through the screwing of the male threaded portion and the female threaded portion, and accordingly, at least one of the upper mold and the lower mold rise and fall. A camera for capturing an image of the gap;
A determination unit is provided that determines whether or not a predetermined amount of fluff is generated based on the image captured by the camera,
3. The impregnation device according to claim 1, wherein the gap adjustment section opens the gap when the determination section determines that a predetermined amount or more of fuzz has been generated. The gap adjustment unit is a servo motor,
3. The impregnation device according to claim 2 , wherein the ball screw is disposed coaxially with a motor shaft of the gap adjustment unit.

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