JP6900417B2 - Method of attaching fiber bundles and method of manufacturing fiber reinforced plastic products - Google Patents

Description

The present invention relates to an apparatus and a technique for manufacturing a fiber reinforced plastic (FRP) product by attaching a fiber bundle impregnated with a resin in advance to a surface to be attached.

A manufacturing method for manufacturing an FRP (Fiber Reinforced Plastics) product is known by forming a fiber bundle such as carbon fiber impregnated with a resin into a tape shape and sticking it on a surface to be stuck. AFP (Auto Faber Placement), etc., which attaches or simply arranges relatively narrow fiber bundles, and ATL (Auto Tape), which attaches or simply arranges relatively wide fiber bundles, are attached to these. It is often called Layup) or the like, but the two are not strictly distinguished. The present invention collectively refers to a manufacturing method in which a fiber bundle and / or a surface to be attached is heated by at least a heating means and the fiber bundle is attached to the surface to be attached, regardless of the width of the fiber bundle to be attached. The fiber bundle affixing device) will be referred to as an ATL device.

In the operation of attaching the fiber bundle to the attachment surface in the ATL device, at least a part of the fiber bundle is held at least temporarily and moves relative to the attachment surface along the attachment path of the fiber bundle. It is usual to use an ATL head (sticking head) that sticks the fiber bundle while heating and / or pressurizing.

As the heating means, non-contact heating means such as a laser or an infrared lamp is often used. As the pressurizing means, a pressing member such as a roller or a shoe that presses the fiber bundle in the normal direction of the non-attached surface while sandwiching the fiber bundle with the surface to be attached is often used. It is desired that the surface to be attached is a free curved surface, and therefore the operation of the ATL head is often required to have three-dimensional (translational, rotational) degrees of freedom. Therefore, the ATL head is often attached to an articulated robot or to a so-called gantry structure that combines orthogonal and rotational movement systems.

Further, the fiber bundle to be attached is usually supplied in a form of being wound around a bobbin, and an ATL device requires a mechanism for unwinding the fiber bundle from the bobbin (referred to as a creel or the like).

There are roughly two types of ATL devices depending on the location of this unwinding mechanism. One is a form in which the unwinding mechanism is mounted on the above-mentioned ATL head itself (hereinafter, this is referred to as a mounted type, and an example thereof is shown in FIG. 6). Is unwound and the fiber bundle is supplied to the ATL head along the transport path (so-called thread path) (hereinafter referred to as a stationary type, and an example is shown in FIG. 7).

Regardless of whether it is a mounted type or a stationary type, the continuous fiber bundle unwound from the bobbin is attached to the surface to be attached for a predetermined length, and then the vicinity of the rear end of the attachment is cut to complete the attaching operation. Is customary. Therefore, it is customary to have a fiber bundle cutting means in the ATL head.

Japanese Patent Publication No. 2014-511781

In the mounted ATL device 30, the ATL head 31 itself has the unwinding mechanism 32, and the bobbin 33 exists in the ATL head 31, so that the transport system (thread) is more complicated than that of the stationary ATL device 40. It has the advantage of not requiring road 45) (see FIGS. 6 and 7).

As described above, the ATL head moves in parallel on the surface to be attached in all directions according to the attachment operation, and itself also swings (rotates or rotates) according to the normal direction of the surface to be attached. .. Therefore, it is necessary to supply the fiber bundle D from the stationary unwinding mechanism 42 (creel) to the ATL head 43 that moves and rotates in all directions. Further, since the fiber bundle D is in the form of a tape, the twist of the fiber bundle D in the thread path 45 is limited, and the fiber bundle D can be reached to the ATL head 43 without twisting one or more turns while maintaining the tape shape. There is a problem that the thread path 45 becomes long and complicated.

In addition, so-called fluff from the fiber bundle D, dirt on the transport member of the thread path 45 due to the impregnated resin that has fallen off, clogging, and the like are often problems because of the long thread path 45.

In particular, when the fiber bundle D is impregnated with a thermosetting resin (this is often called a prepreg tape), the prepreg tape itself has adhesiveness and tackiness on its surface. It is preferable to avoid contact with the transport member, sliding, etc. as much as possible, and there is also a problem that the structure of the thread path 45 and the transport member becomes complicated.

On the other hand, although the above-mentioned stationary type has few problems in the mounted type, there is another problem peculiar to the mounted type.

First of all, since the ATL head 31 itself is equipped with the unwinding mechanism 32, it is often large and heavy. Therefore, an articulated robot 35 equipped with an ATL head 31 and a gantry that are large and have high rigidity are required, and as a result, the cost of the ATL device 30 as a whole is increased. Further, there is a limit to the fiber bundle (bobbin 33) that can be mounted on the ATL head 31, and a problem that the frequency of thread change (bobbin change) is higher than that of the stationary type is likely to occur. This leads to the problem of a decrease in the operating rate of the ATL device as a production device.

Yet another problem is the effect of heat on the fiber bundles from the heating source. The ATL head 31 is equipped with a heating means for the fiber bundle and / or the surface to be attached, and as the heating means, a radiant heat source such as an infrared lamp 8 or a hot air heater is often used. These usually generate a considerable amount of heat during operation.

Further, a laser may be used as a heating source. In this case, the laser oscillation tube itself is usually provided outside the ATL head 31 and the laser light is guided to the ATL head 31 by an optical fiber or the like. Therefore, the heat generated in the ATL head 31 is smaller than that of the radiant heat source and the hot air heater, but the heat generated by the optical members such as the lens and the reflector still exists.

Further, regardless of which heating source is used, the heat from the heating source gradually accumulates in the ATL head 31 with the sticking operation, that is, the heat generation operation of the heating source, and the ATL head 31 itself rises and heats in terms of atmospheric temperature. The phenomenon of being done can also occur.

As a result, there arises a problem that the fiber bundle E mounted on the ATL head 31 before attachment is affected by this heat. When the fiber bundle E is a thermosetting prepreg tape, the adhesiveness and tackiness of the prepreg tape itself described above may be further promoted by the temperature. As a result, there arises a problem that the slidability in the transport path decreases between the unwinding mechanism 32 and the sticking, and the transport resistance increases, or in a remarkable case, the sticking to the transport path causes a transport failure. If it is more remarkable, unwinding failure from the unwinding mechanism 32 occurs, or if it is heated excessively, a part of the thermosetting impregnated resin starts to cure, and the characteristics as a prepreg tape are exhibited. It also occurs when changes and deterioration occur.

In addition, dirt on the transport path surface due to the impregnated resin that has fallen off may be promoted. The above is the case of thermosetting propreg tape, but even in the case of fiber bundles impregnated with thermoplastic resin (hereinafter, this is referred to as UD tape for convenience), problems due to temperature may occur. ..

Generally, the thermoplastic resin impregnated in the UD tape is solid at room temperature, and therefore, unlike the prepreg tape, its surface usually does not have adhesiveness or tackiness. However, when attaching the UD tape, it is necessary to heat at least the thermoplastic resin impregnated in the UD tape to the softening point or the vicinity of the melting point.

For example, polypropylene (hereinafter PP), which has the lowest softening point temperature, is around 150 ° C, and nylon-based (polyamide-based, hereinafter PA), which is frequently used, is around 180 ° C for nylon 6, and nylon 66-based is around 230 ° C, which is even higher. It is said that heat-resistant polyphenylene sulfide (hereinafter referred to as PPS) requires heating at about 280 ° C.

Therefore, it is often necessary to mount a heating source having a large capacity, and as a result, the heat influence from the heating source in the ATL head 31 on the fiber bundle E is often large.

In view of the problems of the prior art described above, it is possible to suppress the increase in size and weight of the ATL head without constructing a long fiber bundle transport path, and further to prevent the heat effect on the fiber bundle from the heating source. There has been a demand for an ATL device that can reduce the amount.

In response to the above problems, in the fiber bundle attaching method according to the first aspect of the present invention, fiber bundles previously cut to a predetermined length are attached one by one to the surface to be attached while being heated and / or pressurized by the attachment head. In the method of sticking a fiber bundle, the sticking head holds and / or conveys only the fiber bundle being stuck and heats at least one of the fiber bundle or the surface to be stuck during the sticking operation of the fiber bundle by the sticking head. ..

In the fiber bundle sticking method according to the first aspect, the sticking head is preferably attached to an articulated robot or a gantry structure.

In the fiber bundle sticking method according to the first aspect, preferably, the fiber bundle housed in the fiber bundle accommodating means for accommodating the fiber bundle is supplied to the sticking head.

In the fiber bundle sticking method according to the first aspect, the fiber bundle is preferably pre-impregnated with resin at least in part.

In the fiber bundle sticking method according to the first aspect, preferably, the fiber bundle contains carbon fibers and the resin is a thermoplastic resin.
The method for producing a fiber-reinforced plastic product according to the second aspect of the present invention includes a step of attaching a fiber bundle to a surface to be attached by the fiber bundle attaching method according to claim 1.

According to the present invention, when a fiber bundle previously cut to a predetermined length, that is, a length to be attached is attached by heating and / or pressurizing with an ATL head, only the fiber bundle during the attaching operation is placed in the ATL head. By presenting it in, other fiber bundles do not continue to exist in the vicinity of the heating source in the ATL head for a long period of time, and the heat effect from the heating source can be reduced.

Further, the fiber bundle is cut to a predetermined length in advance and stored in the fiber bundle accommodating means, and the fiber bundle is supplied to the ATL head one by one by the fiber bundle supplying means to construct a long fiber bundle transport path. It is possible to avoid the problem of increasing the size and weight of the ATL head.

It is a figure which shows the whole ATL apparatus by 1st Embodiment of this invention. It is a side view of the ATL head. It is explanatory drawing of the sticking procedure of the ATL apparatus by 1st aspect. It is a figure explaining the transfer of the fiber bundle from the fiber bundle supply means to the ATL head. It is a figure which shows the whole ATL apparatus by the 2nd aspect by this invention. It is a figure which shows the ATL apparatus by the prior art. It is a figure which shows the ATL apparatus by the prior art.

Hereinafter, embodiments of the present invention will be described with reference to FIG. 1 and below.

FIG. 1 is a diagram showing the entire ATL device 1 according to the first aspect according to the present invention. The ATL device 1 accommodates an articulated robot 2, an ATL head 3 provided at the tip of an arm 2a of the articulated robot, a fiber bundle supply means 4 for supplying a fiber bundle A previously cut to the ATL head 3, and a fiber bundle A. It is composed of a mounting table 13 as a fiber bundle accommodating means, a work 5 having a surface to be attached 5a, a work table 6 on which the work 5 is mounted, and the like.

In the present embodiment, the work 5 is an injection-molded product of a thermoplastic resin, and the purpose of the sticking is to reinforce the work 5 by sticking a cut UD tape A having the same thermoplastic resin on the surface thereof. As a matter of course, the shape of the work 5, the position to which the UD tape A is attached, and the length to which the UD tape A is attached are predetermined.

As the articulated robot 2, a commercially available general-purpose industrial articulated robot can be used. The ATL head 3 is attached to the tip of the arm 2a of the articulated robot.

The ATL head 3 holds and presses the infrared lamp 8 as a heating means, the feeder 9 as a fiber bundle holding and transporting means, and the fiber bundle with the sticking surface 5a of the work 5 on the base material 7, and holds the fiber bundle on the sticking surface 5a. It has at least a pressing means 10 to be attached to. (See Figure 2)
The heating source is not limited to the infrared lamp 8, and a non-contact heating means such as a laser or a hot air source can be used. The infrared lamp 8 has an optical system such as a reflector or a lens (not shown), and collects the emitted infrared rays on the upstream side of the attachment point shown by B in the figure and in the region indicated by the double arrow C in the figure. It heats the surface of the member existing in the region. As a result, the infrared lamp 8 can heat the surface to be heated 5a and the surface side to which the UD tape A is attached in the region.

The feeder 9 for holding and transporting the UD tape A has a set of transport belt pairs 11, and the UD tape A is sandwiched and transported between the transport belts 11a and 11b. Heaters 12a and 12b also exist in the transport belts 11a and 11b, and the transport belts 11a and 11b can be preheated to a predetermined temperature. By transporting the UD tape A between the preheated transport belts 11a and 11b, it is possible to preheat the UD tape A to a predetermined temperature before the UD tape A reaches the attachment point B. This preheating is not essential, and may not be necessary depending on the material, thickness, etc. of the UD tape A and the work 5.

The pressing means 10 includes a pressing roller 10a that affixes the UD tape A to the affixed surface 5a while holding and pressing the UD tape A between the affixed surface 5a and an air cylinder 10b that is a pressing source of the pressing roller.

The fiber bundle supply means 4 is a supply stand 13 (corresponding to a fiber bundle accommodating means) on which UD tape A cut to a predetermined length is loaded in advance, and a pickup hand 14 that picks up UD tape A one by one from the supply stand 13. It consists of gantry shafts 15 and 16 that move the pickup hand 14 vertically and horizontally.

The pickup hand 14 has a plurality of vacuum suction chucks 14a, and picks up only one UD tape A loaded on the supply base 13 by the vacuum suction chuck 14a.

Next, the operation of attaching the UD tape A by the ATL device 1 will be described in order with reference to FIG. The part number notation is omitted for members that are not directly related to the explanation of the pasting operation.

First, as shown in FIG. 3, the pickup hand 14 picks up only one UD tape A on the supply base 13 by the operation of the gantry shafts 15 and 16. At this time, as can be seen in FIG. 3, the vacuum chuck 14a sucks and picks up the UD tape A in a state where both ends (at least one end) of the UD tape A protrude from both ends of the pickup hand 14 in the extending direction.

Next, the pickup hand 14 moves to the delivery position. The UD tape A held by the pickup hand 14 at the delivery position is delivered to the feeder 9 in the ATL head 3. The delivery position is not particularly limited as long as it is within the common area of the movable area of the pickup hand 14 by the gantry axes 15 and 16 and the movable area of the ATL head 3 by the articulated robot 2.

At the delivery position, the articulated robot 2 is such that one end of the UD tape A held by the pickup hand 14 is slightly inserted into the insertion port 20 of the feeder 9 in the ATL head 3 as schematically shown in FIG. Works. When one end of the UD tape A is inserted into the feeder 9 to a predetermined length, the suction of the vacuum chuck 14a is added or removed, and the UD tape A is delivered to the ATL head 3. At the same time, the feeder 9 operates to convey the UD tape A to a predetermined standby position.

The articulated robot 2 is operated again to move the ATL head 3 to the attachment start position. Subsequently, the articulated robot 2 is operated to press the pressing roller 10a against the surface to be attached 5a. At this time, the feeder 9 operates at the timing when the pressing roller 10a comes into contact with the surface to be attached, and the UD tape A is conveyed so that the tip of the UD tape A is sandwiched between the pressing roller 10a and the surface to be attached 5a. .. At this time, the infrared lamp 8 also lights up in synchronization with this timing, and starts heating the surface to be attached 5a and the surface to which the UD tape A is attached.

The ATL head 3 moves and swings on the sticking surface 5a of the work 5 along the sticking path of the UD tape A, and sticks the UD tape A to the sticking surface 5a. During that time (the state shown in FIG. 1), the feeder 9 is operating, and the UD tape A is conveyed and supplied toward the attachment point B.

When the UD tape A is completely attached to the rear end, the infrared lamp 8 is turned off, the pressing of the pressing roller 10a and the surface to be attached 5a is released by the operation of the articulated robot 1, and the application of one UD tape A is completed. ..

Hereinafter, the same operation is repeated, and the UD tape A is attached onto the surface to be attached 5a.

In this embodiment, the gantry structure is used for the fiber bundle supply means 4, but an articulated robot may be used instead.

By the way, in the present invention, a cutting step of cutting the fiber bundle to a predetermined length is required in advance, and various known cutting devices can be used for this. Further, since the cutting mechanism is not required in the ATL head 3, the ATL head 3 is suitable because it leads to weight reduction and simplification.

A step of supplying the cut fiber bundle A to the fiber bundle accommodating means (mounting table 13) is also required, but this may be performed manually, or various known automatic transfer devices and mechanisms may be used. ..

Normally, in an assembly device using such a robot or the like, it is customary to surround the movable range of the robot with a safety fence or the like in order to ensure the safety of workers. At this time, regarding the present invention, for example, the fiber bundle accommodating means (mounting table 13) is arranged outside the safety fence, etc., and the safety fence or the like is provided with an automatically opening / closing door member or the like, and is provided inside the safety fence. The fiber bundle supply means may pick up the fiber bundle A via the door member. In this way, when the fiber bundle A is manually supplied to the mounting table, there is an advantage that it is not necessary to stop the sticking operation of the ATL device 1, which is preferable.

FIG. 5 shows an ATL device 20 according to a second aspect according to the present invention. In the ATL20 device, the gantry structure 21, the linear motion stage 22, and the rotary table 23 are used instead of the articulated robot 2 of the ATL device 1 in the first aspect. The work 6 is placed on the rotary table 23. In FIG. 5, the part number notation is omitted for the members common to those in FIGS. 1 and 2.

In the ATL device 20, the gantry axis 21b is in charge of the x-axis direction translational motion, the linear motion stage 22 is in charge of the y-axis direction translational motion, and the gantry axis 21n is in charge of the z-axis direction translational motion in relation to the attachment operation of the ATL head 3. Regarding the rotational movement, the rotary joint 24 is in charge of the x-axis, the rotary joint 25 is in charge of the y-axis, and the rotary stage 26 is in charge of the z-axis. As a result, each axis translation and rotation degree of freedom during the attachment operation of the ATL head 3 are realized.

The sticking operation in the ATL device 20 is the same as that in the ATL device 1, and the description thereof will be omitted.

1 ATL device 2 Articulated robot 3 ATL head 4 Fiber bundle supply means 5 Work 6 Work base 7 Base material 8 Infrared lamp 9 Feeder
10 Pressing member
10a Pressing roller
11 Conveyance belt pair
11a, 11b Conveyance belt
12a, 12b heater
13 Mounting stand
14 Pickup hand
15, 16 gantry axis
17
20 ATL device
21 Gantry structure
21a, 21b Gantry axis
22 Linear table
23 turntable
24,25 rotary joint
26 rotating stage
30 ATL device
31 ATL head
32 Unwinding mechanism
33 bobbin
35 articulated robot
40 ATL device

Claims (6)

This is a fiber bundle sticking method in which fiber bundles cut to a predetermined length are pasted one by one on the surface to be pasted while being heated and / or pressurized by the sticking head, and the fiber bundle is being stuck by the sticking head. , the application head is only the fiber bundle in the pasting hold and / or transport, heating at least one of the fiber bundle or the object application surface, the fiber bundle sticking method. The fiber bundle sticking method according to claim 1, wherein the sticking head is attached to an articulated robot or a gantry structure. The method for attaching a fiber bundle according to claim 1 or 2, wherein the fiber bundle accommodated in the fiber bundle accommodating means for accommodating the fiber bundle is supplied to the attachment head. The method for attaching a fiber bundle according to any one of claims 1 to 3, wherein the fiber bundle is at least partially impregnated with a resin. The method for attaching a fiber bundle according to claim 4, wherein the fiber bundle contains carbon fibers and the resin is a thermoplastic resin. A method for manufacturing a fiber reinforced plastic product, which comprises a step of attaching a fiber bundle to a surface to be attached by the fiber bundle attaching method according to claim 1.

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