JP7355768B2 - filament winding device - Google Patents

Description

FIELD OF THE INVENTION The present invention relates to a filament winding device.

Molded bodies made of fiber-reinforced resin materials are lightweight and have excellent strength, so they are widely used in various fields. Such molded bodies are usually manufactured by laminating sheet-like base materials called prepregs, which are made by impregnating multiple reinforcing fibers with matrix resin, and then thermosetting the resin under pressure and heating to shape it. . As prepreg, sheet prepreg and narrower tow prepreg are known.

Patent Document 1 describes an invention related to a filament winding device for manufacturing a high-pressure hydrogen tank mounted on a fuel cell vehicle using a fiber-reinforced resin material. In the filament winding device described in Patent Document 1, a fiber bundle (tow prepreg) wound around a bobbin is conveyed along the circumferential surface of a plurality of conveyance rollers (conveyance roller and motor drive roller), and is conveyed by a plurality of eye rollers. It is wrapped around a rotating tank in a suitably widened state. A free roller is arranged downstream of the plurality of conveyance rollers, and the rotational speed of the conveyance roller is controlled based on the rotational speed of the free roller. It is said that this suppresses the wear of the fiber bundle on the conveyance roller, making it possible to manufacture a tank with stable quality.

Japanese Patent Application Publication No. 2019-55831

By the way, even if the tow prepreg is homogeneously impregnated with fiber-reinforced resin with a uniform fiber width, the thickness of the tow prepreg may vary due to fluctuations in the fiber width during transportation in a filament winding device. This may occur. When the thickness of the tow prepreg varies, unevenness tends to occur on the surface of the molded product. As a result, the strength of the molded body in the circumferential direction and the axial direction tends to become uneven, making it difficult to stabilize the quality of the molded body. Therefore, in order to stabilize the quality of the molded body, it is necessary to increase the amount of tow prepreg wrapped around the molded body, resulting in a thickened molded body and an increase in weight. This goes against the trend in the world of reducing the weight of various parts mounted on vehicles, for example, from the perspective of improving vehicle fuel efficiency. Furthermore, weight reduction of parts is required not only in the field of transportation such as vehicles, but also in molded bodies applied to various other fields.

The present invention was made to solve these conventional problems, and its purpose is to provide a filament winding device that can form a thin-walled molded product with stable quality.

In order to solve the above problems, the present invention includes a conveyance section in which a plurality of conveyance rollers are arranged and conveys the tow prepreg along the circumferential surface thereof, and a winding section that wraps the conveyed tow prepreg around a core material. In the filament winding device, the core material is rotated at a predetermined rotational speed in the winding section, and in the conveyance section, the tension of the tow prepreg conveyed from each of the conveyance rollers is It is controlled so that it increases in stages from the side to the downstream side.

If you try to convey the tow prepreg under high tension, the reinforcing fibers that make up the tow prepreg will bite into each other as the tow prepreg overlaps in the stacking direction when unwinding the bobbin on which the tow prepreg is wound. It's easy to get into a situation like this. As a result, the tow prepreg cannot be unrolled smoothly, and the fiber width tends to fluctuate. Further, when the tow prepreg is conveyed under a large tension, the tow prepreg becomes slippery on the circumferential surface of the conveyance roller, and only the conveyance roller rotates. This also makes it impossible to unwind the tow prepreg smoothly, and the fiber width tends to fluctuate.

According to the above configuration, the conveyance section controls the plurality of conveyance rollers so that the tension of the tow prepreg conveyed from the conveyance rollers increases stepwise from the upstream side to the downstream side. Therefore, on the upstream bobbin, the tension when unwinding the tow prepreg can be kept small, while on the downstream conveyance roller, a large tension can be applied to the tow prepreg.

This makes it difficult for the reinforcing fibers to bite into each other when unwinding the tow prepreg, and the tow prepreg being transported becomes difficult to slip on the circumferential surface of each transport roller. As a result, the unwinding of the tow prepreg becomes smooth, and the tow prepreg is conveyed between the plurality of conveyance rollers with a stable fiber width. In addition, since a large tension is applied to the conveying roller on the downstream side, the resin in the tow prepreg oozes out when being conveyed along the circumferential surface of the conveying roller, reducing its thickness and increasing the fiber volume content Vf. do. In this way, the tow prepreg is transported between the plurality of transport rollers with a stable fiber width and has a high fiber volume content Vf. Therefore, even if the molded product is thin, it is possible to mold a molded product with stable quality. Further, even if the molded product is thin, it is possible to mold a molded product with excellent strength.

In the above configuration, it is preferable that the rotational torque of the plurality of conveyance rollers is controlled in the conveyance section.
According to the above configuration, since the rotation of the conveyance roller is controlled by the rotational torque, even if the diameters of the plurality of conveyance rollers are different, the tension applied to the tow prepreg can be easily adjusted, and the conveyance speed of the tow prepreg can be adjusted. can be easily done.

In the above configuration, it is preferable that, in the conveyance section, the plurality of conveyance rollers are arranged such that contact lengths of the tow prepreg with respect to the circumferential surfaces of the plurality of conveyance rollers are substantially the same.
According to the above configuration, it is possible to increase the rotational torque of the plurality of conveyance rollers to the same extent. Therefore, the rotational torque of the plurality of conveyance rollers can be managed by one control section. Control can be simplified and the device configuration can be simplified. Note that "substantially the same" here includes not only the case where the contact length of the tow prepreg with the circumferential surface of a plurality of conveyance rollers is completely the same, but also the case where the contact length is within an error range of about ±20%, for example. .

The above configuration includes a detection unit that detects the tension of the tow prepreg conveyed from the most downstream conveyance roller, and the conveyance unit detects the most of the plurality of conveyance rollers based on the detected tension value. The tension applied to the tow prepreg on the downstream side is controlled, and the tension of the tow prepreg conveyed from each of the conveyance rollers is controlled so as to increase stepwise from the upstream side to the downstream side. It is preferable.

According to the above configuration, the tension of the tow prepreg being conveyed by the conveyance roller is controlled based on the tension applied to the tow prepreg before being wound around the core material, so the tension applied to the tow prepreg is managed to a targeted value. Easy to do. By being able to manage the tension applied to the tow prepreg to a targeted value, it is easy to manage the fiber volume content Vf (%) of the tow prepreg to a targeted value.

According to the present invention, a thin-walled molded article with stable quality can be molded.

FIG. 1 is a schematic diagram of a filament winding device of this embodiment. 5 is a flowchart illustrating control of rotational torque of a conveyance roller in a filament winding device. FIG. 3 is a diagram illustrating a state in which tow prepreg is transported by a transport roller. The figure which shows the relationship between the tension applied to tow prepreg and fiber volume content Vf. 7 is a flowchart illustrating an example of changing the control of the rotational torque of the conveyance roller.

Hereinafter, a filament winding device (hereinafter referred to as FW device) embodying the present invention will be described based on FIG. 1.
The material of the fiber-reinforced resin constituting the molded body is not particularly limited, and the resin and reinforcing fibers constituting the fiber-reinforced resin can be appropriately selected from conventionally known ones. For example, examples of the resin constituting the fiber-reinforced resin include thermosetting resins such as epoxy resin, polyester resin, and phenol resin. Furthermore, examples of the reinforcing fibers constituting the fiber-reinforced resin include carbon fibers, glass fibers, aramid fibers, and the like.

As shown in FIG. 1, the FW device 1 of this embodiment includes an unwinding section 10, a conveyance section 20, a winding section 30, a control section 40, a detection section 50, and an input section 60.
The unwinding section 10 is provided with a bobbin 11, and a tow prepreg T in which a reinforcing fiber bundle is impregnated with resin is wound around the bobbin 11. The tow prepreg T is unwound from the bobbin 11 and conveyed in the direction shown by arrow A in FIG. That is, in FIG. 1, the left side is the upstream side of the FW device 1, and the right side is the downstream side of the FW device 1.

The conveyance section 20 is provided with a tension roller 21, a conveyance roller 22, and an eye tip roller 23 from the upstream side. The tension roller 21 is a roller for applying a predetermined tension to the tow prepreg T and unwinding the tow prepreg T from the bobbin 11. A plurality of conveyance rollers 22 are provided and are rollers for conveying the tow prepreg T along its circumferential surface. In this embodiment, five conveyance rollers 22 are provided. The eye cutter roller 23 is a roller that applies appropriate pressure to the tow prepreg T and conveys the tow prepreg T while maintaining its fiber width.

The five conveyance rollers 22 are arranged in such a positional relationship that the contact lengths of the tow prepreg T with the circumferential surface thereof are approximately the same when the tow prepreg T is conveyed. Specifically, if the five conveyance rollers 22 are conveyance rollers 22a, 22b, 22c, 22d, and 22e in order from the upstream side, the contact length of the tow prepreg T with the circumferential surface of the conveyance roller 22a is the conveyance roller 22b. This is approximately the same as the contact length of the tow prepreg T with the circumferential surface of the tow prepreg T. Similarly, the contact lengths of the tow prepreg T with the circumferential surfaces of the conveyance rollers 22c, 22d, and 22e are also approximately the same.

The conveyance roller 22 is provided with a rotational torque drive section 24 . The rotational torque drive unit 24 is controlled by a control unit 40 that will be described later. In this embodiment, five conveyance rollers 22 are configured to be driven by one rotary torque drive unit 24.

The winding portion 30 is provided with a mandrel 31 as a core material. The mandrel 31 is a cylindrical hollow body or solid body having the size of the molded body to be manufactured, and is formed to have an outer diameter of 90 cm and a length of 100 cm, for example.

The control section 40 includes a conveyance roller control section 41 , a feed speed control section 42 , a tension roller control section 43 , an eye roller control section 44 , and a rotation speed control section 45 .
The conveyance roller control section 41 is connected to the rotational torque drive section 24 of the conveyance section 20. The conveyance roller control section 41 controls the rotational torque of the conveyance roller 22 by driving the rotational torque drive section 24 based on a detected value of the tension applied to the tow prepreg T detected by a detection section 50 which will be described later.

The feed speed control section 42 is connected to the bobbin 11 of the unwinding section 10 and controls the unwinding speed of the tow prepreg T. The tension roller control section 43 is connected to the tension roller 21 of the conveyance section 20, and controls the tension applied to the tow prepreg T unwound from the bobbin 11 by adjusting the rotational torque or height of the tension roller 21. The eye tip roller control section 44 is connected to the eye tip roller 23, adjusts the height of the eye tip roller 23, and controls the pressure with which the tow prepreg T is pressed against the circumferential surface of the eye tip roller 23. By adjusting the height of the eye opening roller 23, the tow prepreg T conveyed from the conveying roller 22 is pressed against the circumferential surface of the eye opening roller 23, and the fiber width of the tow prepreg T is maintained. The rotational speed control section 45 is connected to the mandrel 31 and controls the rotational speed of the mandrel 31.

The detection unit 50 is configured as a contact type tension detection sensor provided on the eye roller 23. The tension detection sensor detects the tension applied to the tow prepreg T on the downstream side of the eye cutter roller 23, acquires it as a detected value, converts the detected value into an electric signal (tension detection signal ST), and sends it to the control unit at predetermined intervals. It outputs to the conveyance roller control section 41 of 40.

The input unit 60 inputs, as initial settings when driving the FW device 1, the feed speed of the bobbin 11, the rotational torque or height of the tension roller 21, the height of the eye roller 23, and the tension applied to the tow prepreg T on the downstream side of the eye roller 23. The target value of the mandrel 31 and the rotational speed of the mandrel 31 can be input to the control unit 40. From these input values, a rotational torque signal SR is output from the conveyance roller control section 41 to the rotational torque drive section 24 of the conveyance section 20 based on the map stored in the control section 40, and the rotational torque of the conveyance roller 22 is set to the initial value. set to the value.

Next, tension control for the tow prepreg T in the FW device 1 will be explained.
In the FW device 1, the rotational torque of the plurality of conveyance rollers 22 is controlled based on the detected value of the tension applied to the tow prepreg T by the tension detection sensor of the detection unit 50. By controlling the rotational torque of the plurality of conveyance rollers 22, the tension applied to the tow prepreg T conveyed from the most downstream conveyance roller 22e among the plurality of conveyance rollers 22 is set to a predetermined value, and the tension of each The tension of the tow prepreg T conveyed from the conveyance roller 22 is set to increase stepwise from the upstream side to the downstream side.

Prior to conveying the tow prepreg T in the FW device 1, first, the fiber width of the tow prepreg T wound around the bobbin 11, the resin content Rc, the number of reinforcing fibers in the fiber bundle, the material of the reinforcing fibers, and the applied Initial settings of the FW device 1 are performed from the input section 60 based on the material of the resin and the like. Specifically, the feed speed of the bobbin 11, the rotational torque or height of the tension roller 21, the height of the eye roller 23, the target value of the tension applied to the tow prepreg T downstream of the eye roller 23, the rotation speed of the mandrel 31, etc. is input from the input section 60. Further, the fiber width of the tow prepreg T is inputted from the input section 60. Each input value input from the input section 60 is sent to the control section 40.

The input value regarding the feed speed of the bobbin 11 is outputted from the feed speed control section 42 to the bobbin 11 as an initial value. Thereby, the bobbin 11 rotates at a predetermined rotational speed, and the tow prepreg T is unwound at a predetermined unwinding speed. The input value regarding the rotational torque or height of the tension roller 21 is outputted from the tension roller control section 43 to the tension roller 21 as an initial value, and a predetermined tension is applied to the tow prepreg T unwound from the bobbin 11. The input value regarding the height of the eye tip roller 23 is outputted from the eye tip roller control unit 44 to the eye tip roller 23 as an initial value, and the tow prepreg T being conveyed is pressed against the circumferential surface of the eye tip roller 23 to apply a predetermined pressure. The input value regarding the rotational speed of the mandrel 31 is outputted from the rotational speed control section 45 to the mandrel 31 as an initial value, and the mandrel 31 rotates at a predetermined rotational speed. Further, the target value of the tension applied to the tow prepreg T on the downstream side of the eye opening roller 23, which is input from the input unit 60, is stored in the control unit 40 as an initial value of the tension applied to the tow prepreg T conveyed from the eye opening roller 23.

In the control section 40 , a rotational torque signal SR for setting the rotational torque of the conveyance roller 22 is outputted from the conveyance roller control section 41 to the rotational torque drive section 24 based on the map stored in the control section 40 . The rotational torque of the conveyance roller 22 is set to an initial value by the rotational torque signal SR here.

The FW device 1 is provided with one rotary torque drive section 24 for five conveyance rollers 22, and the five conveyance rollers 22 are driven by one rotary torque drive section 24. The rotational torque signal SR output from the conveyance roller control section 41 drives the rotational torque drive section 24 so that the tension applied to the tow prepreg T conveyed from each conveyance roller 22 increases step by step with the same raising width. let Specifically, when the tension on the tow prepreg T conveyed from the most downstream conveyance roller 22e is set to be X (kgf), the tow prepreg T conveyed from the most upstream conveyance roller 22a is , X/5 (kgf) is applied to the tow prepreg T, which is conveyed from the downstream conveyance roller 22b. The rotational torque drive unit 24 is driven so that a tension of 3X/5 (kgf) is applied to the prepreg T. In the FW device 1, the five conveyance rollers 22 are arranged in a positional relationship such that the contact length of the tow prepreg T with the circumferential surface during conveyance of the tow prepreg T is approximately the same. The torque drive unit 24 can control the rotational torque of all the conveyance rollers 22 so that they increase by the same amount.

As shown in the flowchart of FIG. 2, the tension detection sensor of the detection unit 50 is configured to detect the value of tension applied to the tow prepreg T at predetermined intervals. In step S11, the detected tension value is converted into a tension detection signal ST and input to the conveyance roller control section 41 of the control section 40.

In step S12, the conveyance roller control unit 41 determines whether the detected tension value has a variation width greater than a predetermined value with respect to the target tension value. If it is determined that the fluctuation range is not greater than the predetermined range, the rotational torque signal SR from the conveyance roller control section 41 to the rotational torque drive section 24 is not output. If it is determined that the fluctuation range is greater than the predetermined value, the process advances to step S13.

In step S13, it is determined whether the detected tension value is smaller than the target tension value. If it is determined that the detected tension value is smaller than the target tension value, the conveyance roller control unit 41 calculates a target value for increasing the rotational torque of the conveyance roller 22 . Then, in step S14, a rotational torque signal SR is transmitted from the conveyance roller control unit 41 to the rotational torque drive unit 24, and the rotational torque drive unit 24 is driven so that the rotational torque of the conveyance roller 22 reaches the target increase range. .

On the other hand, if it is determined that the detected tension value is larger than the target tension value, the conveyance roller control unit 41 calculates a target value for decreasing the rotational torque of the conveyance roller 22 . Then, in step S15, a rotational torque signal SR is transmitted from the conveyance roller control unit 41 to the rotational torque drive unit 24, and the rotational torque drive unit 24 is driven so that the rotational torque of the conveyance roller 22 reaches the target lowering range. let

In this manner, the FW device 1 detects the tension applied to the tow prepreg T at predetermined time intervals, and controls the rotational torque of the conveyance roller 22 based on the detected value. As a result, the tension applied to the tow prepreg T conveyed from the eye opening roller 23 is controlled to approach the target value, and the tension applied to the tow prepreg T conveyed from the five conveyance rollers 22 is controlled from the upstream side to the downstream side. The width is controlled so that it gradually increases in the same width as you go.

Next, a method for manufacturing a fiber-reinforced resin molded body using the FW device 1 will be described along with its operation.
The manufacturing method of the molded article includes a fiber opening step of opening fiber bundles of reinforcing fibers in a so-called dry state before being impregnated with resin, and a resin-spreading step of impregnating the spread reinforcing fibers with resin to obtain tow prepreg T. A coating process, a filament winding process in which the tow prepreg T is transported by the FW device 1 and wound around a mandrel 31 to obtain an intermediate, a wrapping process in which a wrapping tape is wrapped around the circumferential surface of the intermediate, and an intermediate body wrapped with the wrapping tape is It has a molding step of heating to obtain a molded body. The opening process, resin coating process, wrapping process, and molding process can be performed by conventionally known methods.

For example, the opening process includes a method in which a dry fiber bundle running under a constant tension is rubbed with a roll, a method in which an air flow is applied to the fiber bundle while the fiber bundle is bent, and the like. By going through the opening process, the waviness of the fiber bundle is suppressed, so-called fiber unevenness is reduced, and the thickness can be reduced. Moreover, the fiber width becomes constant over the entire length, and the amount of resin applied in the resin application process can be stabilized.

The resin application process can be carried out by dipping the opened fiber bundle in a resin bath while being conveyed along a conveyor roller, or by placing the fiber bundle along the circumference of an oiling roller to which a certain amount of resin is supplied. Examples include a method of transporting. By going through the resin application step, a certain amount of resin can be applied to the spread fiber bundle. The tow prepreg T that has undergone the resin coating process is arranged to have a predetermined fiber width, and the resin content Rc (wt%) is stable over the entire length of the tow prepreg T. The tow prepreg T is wound onto a bobbin 11 and supplied to a filament winding process.

The filament winding process is performed using the FW device 1. First, initial settings of the FW device 1 are performed from the input section 60. The tow prepreg T is unwound from the bobbin 11 under a predetermined tension at a predetermined unwinding speed. Further, the tension is increased in stages along the circumferential surface of the conveyance roller 22 and the sheet is conveyed to the eye tip roller 23 . The eye cutter roller 23 conveys the tow prepreg T to the mandrel 31 while maintaining its fiber width, and winds the tow prepreg T around the mandrel 31 .

In the filament winding process, the above control is performed based on the detected value of the tension applied to the tow prepreg T by the detection unit 50 in the FW device 1. Therefore, when the tow prepreg T is unwound, the reinforcing fibers are less likely to bite into each other, and the tow prepreg T is less likely to slip on the circumferential surface of each transport roller 22 while being transported. As a result, the tow prepreg T is transported between the plurality of transport rollers 22 with the fiber width being stabilized.

Further, as shown in FIG. 3, when the tow prepreg T under tension is conveyed along the circumferential surface of the conveying roller 22, the tow prepreg T is pressed against the circumferential surface of the conveying roller 22 and tends to become flat. . In the tow prepreg T pressed against the peripheral surface of the conveyance roller 22, the impregnated resin R oozes out in the width direction due to the pressure, and as a result, the fiber volume content Vf of the tow prepreg T increases. By increasing the tension stepwise, a large tension is applied to the tow prepreg T transported from the most downstream transport roller 22e. As the tension increases, the resin in the tow prepreg T oozes out more easily, its thickness becomes thinner, and the fiber volume content Vf increases.

FIG. 4 shows a graph showing the relationship between the tension applied to the tow prepreg T and the fiber volume content Vf. As shown in FIG. 4, in the tension range up to 1.5 kgf, the value of the fiber volume content Vf tends to increase as the tension applied to the tow prepreg T increases. In this way, by conveying the tow prepreg T while applying tension in stages in the filament winding process, the fiber width is kept constant, the fiber volume content Vf is improved, and the quality of the tow prepreg T is improved. becomes stable.

The wrapping process is performed by winding a known wrapping tape around the circumferential surface of an intermediate body formed by winding the tow prepreg T around the mandrel 31. By going through the wrapping process, an appropriate pressure can be applied to the circumferential surface of the intermediate body, thereby suppressing the generation of voids in the resin and suppressing the generation of uneven shapes in the subsequent molding process.

In the molding process, for example, the intermediate is heated in a mold or heated in a heating furnace, thereby thermosetting the resin. At this time, the heat shrinkage of the wrapping tape applies pressure to the intermediate body from its outer circumferential surface, and the thermosetting of the resin progresses, which suppresses the formation of voids within the resin and prevents the formation of uneven shapes on the surface. suppressed.

Next, the effects of the above embodiment will be explained.
(1) A plurality of conveyance rollers 22 are arranged in the conveyance section 20 of the FW device 1, and in the conveyance section 20, the tension of the tow prepreg T conveyed from the conveyance rollers 22 is gradually increased from the upstream side to the downstream side. It is controlled to increase in size.

Therefore, a large tension can be applied to the tow prepreg T conveyed from the most downstream side. The thickness of the tow prepreg T becomes thinner, and the fiber volume content Vf improves. Thereby, a molded article with excellent strength can be molded even if it is thin.

(2) The tension of the tow prepreg T conveyed from the conveyance roller 22 is controlled to increase stepwise from the upstream side to the downstream side.
Therefore, sudden large tension is suppressed from being applied to the tow prepreg T being transported. When the tow prepreg T is unwound from the bobbin 11, the reinforcing fibers constituting the tow prepreg T are prevented from digging into each other, and the tow prepreg T can be unwound smoothly. This suppresses fluctuations in fiber width and suppresses variations in fiber width over the entire length of the tow prepreg T.

(3) Since a sudden large tension is suppressed from being applied to the tow prepreg T being transported, the tow prepreg T is difficult to slip on the circumferential surface of the transport roller 22. The tow prepreg T can be unrolled smoothly, and fluctuations in the fiber width of the tow prepreg T are suppressed. The quality of the molded product is stable.

(4) In the conveyance section 20 of the FW device 1, the tension applied to the tow prepreg T conveyed by the conveyance roller 22 is adjusted by controlling the rotational torque of the conveyance roller 22.
Therefore, even if the diameters of the plurality of conveyance rollers 22 are different, the tension applied to the tow prepreg T can be easily adjusted, and the conveyance speed of the tow prepreg T can be easily adjusted.

(5) In the conveyance section 20 of the FW device 1, the plurality of conveyance rollers 22 are arranged so that the contact length of the tow prepreg T with the circumferential surface thereof is approximately the same.
Therefore, even if there are a plurality of conveyance rollers 22, the increase in the rotational torque of the conveyance rollers 22 can be made the same. Thereby, the rotational torque of the plurality of conveyance rollers 22 can be managed by one rotational torque drive unit 24. The tension of the tow prepregs T from the plurality of conveyance rollers 22 can be controlled by one rotational torque signal SR from the conveyance roller control section 41. Control of the tension applied to the tow prepreg T can be simplified, and the configuration of the FW device 1 can be simplified.

(6) A detection unit 50 that detects the tension applied to the tow prepreg T is provided downstream of the most downstream conveyance roller 22e and immediately before the mandrel 31 of the winding unit 30. Then, the tension of the tow prepreg T in the conveyance section 20 is controlled based on the detected tension value detected by the detection section 50.

Therefore, the tension can be brought close to the target value, and the tow prepreg T can be wound around the mandrel 31 while the fiber volume content Vf is well controlled. The quality of the molded body can be improved.

(7) In the conveyance unit 20, based on the detected value of the tension applied to the tow prepreg T, the tension applied to the tow prepreg T at the most downstream side of the plurality of conveyance rollers 22 is controlled, and the tow prepreg T is conveyed from each conveyance roller 22. The tension of the tow prepreg T is controlled to increase stepwise from the upstream side to the downstream side.

Therefore, the tension applied to the tow prepreg T can be easily controlled to a targeted state, and the fiber volume content Vf can be brought close to the targeted value.
(8) The method for manufacturing a molded body using the FW device 1 includes a fiber opening process and a resin coating process before the filament winding process. In the opening step, a fiber bundle of reinforcing fibers in a so-called dry state before being impregnated with resin is opened.

Therefore, in the tow prepreg T supplied to the FW device 1, waviness of the fiber bundle is suppressed, so-called fiber unevenness is reduced, and the thickness thereof is reduced. Furthermore, since the fiber width is constant over the entire length, the amount of resin applied in the resin application process can be stabilized.

(9) In the resin application step, the reinforcing fiber bundles opened in the opening step are impregnated with resin.
Therefore, a certain amount of resin can be applied, and the resin content Rc (wt%) is stabilized over the entire length of the tow prepreg T.

(10) The tow prepreg T, whose fiber width and resin content Rc have been stabilized through the opening process and the resin coating process, is transported while controlling the tension using the FW device 1.
Therefore, the tow prepreg T of good quality can be wound around the mandrel 31 while maintaining its state. Furthermore, it is possible to suppress the occurrence of unevenness in the state of being wound around the mandrel 31. A molded article with excellent quality can be obtained.

(11) Since a large tension can be applied to the tow prepreg T, the fiber volume content Vf of the tow prepreg T can be improved, and variations in the thickness of the tow prepreg T can be suppressed.

Therefore, the number of laminated tow prepregs T for forming a molded body can be reduced, and generation of gaps between the multiple layers of tow prepregs T is suppressed. This suppresses the generation of voids due to gaps during the wrapping process and molding process. A molded article with good quality can be produced.

The above embodiment can be modified as follows. Note that the above embodiment and the following modification examples can be applied in combination with each other within a technically consistent range.
- Although five conveyance rollers 22 are provided in the conveyance section 20, the number is not particularly limited. The number can be set to an appropriate number depending on the magnitude of the tension applied to the tow prepreg T, the width of increase in tension, the diameter of the conveyance roller 22, etc.

- The plurality of conveyance rollers 22 may all have the same diameter, or may have a mixture of different diameters, or may all have different diameters.
- The configuration of the tension roller 21 is not particularly limited. The tension of the tow prepreg T may be adjusted together with a known active dancer roller.

- The tension roller 21 and the eye roller 23 may be omitted. If the eye roller 23 is omitted, the tension detection sensor of the detection unit 50 may be provided on the most downstream conveyance roller 22e.

- The number of rotational torque drive units 24 may not be one, but may be provided separately for each conveyance roller 22, for example.
- The plurality of conveyance rollers 22 do not need to be arranged so that the length of contact with the circumferential surface of the tow prepreg T is approximately the same.

- The configuration of the control unit 40 is not limited to that of the above embodiment. For example, the feed speed control section 42 and the tension roller control section 43 may not be provided.
- The amount of increase in the rotational torque may not be substantially the same, and the amount of increase in the tension of the tow prepreg T conveyed from the conveyance roller 22 may not be substantially the same. The amount of increase is not particularly limited as long as it increases gradually from the upstream side to the downstream side. The amount of increase in rotational torque and the amount of increase in tension can be appropriately set within a range that does not cause slippage of the tow prepreg T on the circumferential surface of the conveyance roller 22 or fluctuation of the fiber width.

- In the above embodiment, the detection unit 50 detects the tension applied to the tow prepreg T, and based on the detected value, the conveyance unit 20 detects the tension applied to the tow prepreg T at the most downstream side of the plurality of conveyance rollers 22. At the same time, the tension of the tow prepreg T conveyed from each conveyance roller 22 is controlled to increase stepwise from the upstream side to the downstream side. However, the object detected by the detection unit 50 is not limited to tension. The fiber width of the tow prepreg T may be used, or the thickness of the tow prepreg T may be used. Furthermore, the control mode is not limited to that of the above embodiment.

For example, a case where the detection unit 50 is configured with a width detection sensor that detects the fiber width of the tow prepreg T on the downstream side of the eye cutter roller 23 will be described. Examples of the width detection sensor include a sensor including a light projecting section and a light receiving section. The width detection sensor converts a change in the amount of light that reaches the light receiving section into an electrical signal and outputs the electrical signal when the light projected from the light projecting section is blocked by the tow prepreg T. For example, when the tow prepreg T passes through the width detection sensor, the width detection sensor detects the positions of both edges of the tow prepreg T in the width direction based on changes in the amount of light reaching the light receiving part, and then determines the position of the tow prepreg T from the detected value. Obtain the fiber width value of prepreg T. The fiber width value is converted into an electrical signal and outputted to the conveyance roller control section 41 of the control section 40 at predetermined time intervals.

As a control mode in this case, a flowchart as shown in FIG. 5 can be considered. First, the input value of the fiber width of the tow prepreg T inputted from the input section 60 is stored in the control section 40 as the initial value of the fiber width of the tow prepreg T.

The detection section 50 is configured to detect the value of the fiber width when the tow prepreg T passes through the detection section 50 at predetermined time intervals. In step S21, the detected value of the fiber width is converted into a width detection signal and input to the conveyance roller control section 41 of the control section 40.

In step S22, the conveyance roller control unit 41 determines whether the detected value of the fiber width is within a predetermined range of variation or more with respect to the initial value of the fiber width. If it is determined that the fluctuation range is not greater than the predetermined range, the rotational torque signal SR from the conveyance roller control section 41 to the rotational torque drive section 24 is not output. If it is determined that the variation range is greater than the predetermined value, the process advances to step S23.

In step S23, it is determined whether the detected value of the fiber width is smaller than the initial value of the fiber width. When it is determined that the detected value of the fiber width is smaller than the initial value of the fiber width, the conveyance roller control unit 41 calculates a target value for increasing the rotational torque of the conveyance roller 22. Then, in step S24, the conveyance roller control section 41 transmits a rotational torque signal SR to the rotational torque drive section 24, and drives the rotational torque drive section 24 so that the rotational torque of the conveyance roller 22 increases to the target value. let

On the other hand, if it is determined that the detected value of the fiber width is larger than the initial value of the fiber width, the conveyance roller control section 41 calculates a target value for the amount of decrease in the rotational torque of the conveyance roller 22. Then, in step S25, the rotational torque signal SR is transmitted from the conveyance roller control unit 41 to the rotational torque drive unit 24, and the rotational torque drive unit 24 is activated so that the rotational torque of the conveyance roller 22 falls within the range of the target value. drive.

In this way, by detecting the fiber width of the tow prepreg T at predetermined intervals and controlling the rotational torque of the conveyance roller 22 based on the detected value, the fiber width of the tow prepreg T can be adjusted while being conveyed by the conveyance roller 22. fluctuations are suppressed.

- In the winding part 30, a temperature adjustment mechanism may be mounted on the mandrel 31 as a core material. Examples of the temperature adjustment mechanism include a structure in which a heat source such as an IH heater is disposed inside the mandrel 31, a structure in which a high-temperature fluid serving as a heat source is circulated inside the mandrel 31, and the like. In this case, the temperature control section 40 may be provided with a temperature control section, and the temperature control section may be connected to the temperature adjustment mechanism of the mandrel 31 to control the temperature of the mandrel 31. Further, the temperature of the mandrel 31 may be input from the input unit 60 as an initial setting when driving the FW device 1. The input value regarding the temperature of the mandrel 31 is outputted from the temperature adjustment section to the temperature adjustment mechanism as an initial value, and the heat source is set to a predetermined temperature.

In this way, by mounting the temperature adjustment mechanism on the mandrel 31, the temperature change of the mandrel 31 during molding is suppressed, and the outer diameter dimension of the mandrel 31 can be stabilized. Thereby, the quality of the molded article can be improved.

- The method for manufacturing the molded body is not limited to the case where the tow prepreg T is prepared through a fiber opening process and a resin coating process. A commercially available tow prepreg T wound around a bobbin may be procured. If the fiber width and resin content Rc of the tow prepreg T are appropriately controlled, the state of the tow prepreg T can be maintained during transportation by the FW device 1.

Technical ideas that can be derived from the above embodiments and modified examples will be added below.
(a) A method for producing a molded article made of fiber-reinforced resin by a filament winding method, which includes a conveying step of conveying tow prepreg along the circumferential surface of a plurality of conveying rollers, and a conveying step of conveying the conveyed tow prepreg to a core material. A winding step of winding the intermediate body around the periphery to form an intermediate body, and a molding process of thermosetting the intermediate body to form a molded body, and in the winding process, the core material is rotated at a predetermined rotational speed, A method for manufacturing a molded article, characterized in that, in the conveyance step, the tension of the tow prepreg conveyed from the conveyance roller is controlled to increase stepwise from the upstream side to the downstream side.

(b) The method for manufacturing a molded body according to (a) above, wherein in the conveying step, the rotational torque of the plurality of conveying rollers is controlled.
(c) In the conveyance step, the tension applied to the tow prepreg at the most downstream side of the plurality of conveyance rollers is calculated based on the detected value of the fiber width of the tow prepreg at the most downstream side of the plurality of conveyance rollers. (a) or (b) above, characterized in that the tension of the tow prepreg conveyed from each of the conveyance rollers is controlled to increase stepwise from the upstream side to the downstream side. A method for producing a molded article as described in .

(d) A manufacturing system for manufacturing a fiber-reinforced resin molded article by a filament winding method, which includes a conveyance section in which a plurality of conveyance rollers are arranged and conveys tow prepreg along the circumferential surface thereof, and a conveyance section for conveying tow prepreg along the circumferential surface thereof, and A winding section that wraps the tow prepreg around a core material, a detection section that detects the fiber width of the tow prepreg at the most downstream side of the plurality of conveyance rollers, and the tow prepreg that is conveyed from each of the conveyance rollers. The control unit controls the tension applied to the tow prepreg at the most downstream side of the plurality of conveyance rollers based on the detected value of the fiber width by the detection unit. Further, the manufacturing system is characterized in that the tension of the tow prepreg conveyed from each of the conveyance rollers is controlled to increase stepwise from the upstream side to the downstream side.

(E) A conveyance section in which a plurality of conveyance rollers are arranged and convey the tow prepreg along the circumferential surface thereof, a winding section that wraps the conveyed tow prepreg around a core material, and a plurality of conveyance rollers. comprising a detection unit that detects at least one of the fiber width and thickness of the tow prepreg at the most downstream side, in the winding unit, the core material is rotated at a predetermined rotational speed, and in the conveyance unit, Based on the detected value, the tension applied to the tow prepreg at the most downstream side of the plurality of conveyance rollers is controlled, and the tension of the tow prepreg conveyed from each of the conveyance rollers is controlled from the upstream side to the downstream side. A filament winding device characterized in that the filament winding device is controlled to gradually increase in size as it goes to the side.

T... Tow prepreg, 1... Filament winding device, 10... Unwinding section, 11... Bobbin, 20... Conveyance section, 21... Tension roller, 22, 22a, 22b, 22c, 22d, 22e... Conveyance roller, 23... Eye cutter roller, 30... Winding section, 31... Mandrel (core material), 40... Control section, 41... Conveyance roller control section, 50... Detection section.

Claims (3)

a conveying section in which a plurality of conveying rollers are arranged and conveying tow prepreg along the circumferential surface thereof;
a winding unit that winds the transported tow prepreg around a core material;
a detection unit that is disposed downstream of the conveyance roller that is disposed most downstream and detects any one of the tension of the tow prepreg, the fiber width of the tow prepreg, and the thickness of the tow prepreg;
and a control unit that controls the rotational torque of the plurality of conveyance rollers,
In the winding section, the core material is rotated at a predetermined rotational speed,
The control unit controls the rotational torque based on the detected value by the detection unit, so that the tension of the tow prepreg conveyed from each of the conveyance rollers is gradually increased from the upstream side to the downstream side. A filament winding device characterized by increasing the size of the filament. an unwinding section provided with a bobbin around which the tow prepreg is wound;
The control unit sets each initial value of the rotational speed of the bobbin, the target value of the tension of the tow prepreg in the detection unit, and the rotational speed of the core material, and sets the detected value in the detection unit and the target value. The filament winding device according to claim 1, wherein the rotational torque is controlled by comparing the rotational torque with the rotational torque. The filament winding device according to claim 1 or 2, wherein in the conveyance section, the plurality of conveyance rollers are arranged so that contact lengths of the tow prepreg with the circumferential surface of the plurality of conveyance rollers are approximately the same. .