A winding head for at least two fiber strands and a winding method for manufacturing a fiber-reinforced component

Abstract

The invention relates to a winding method and a winding head for the manufacture of fiber-reinforced components by winding a winding support with resin-impregnated fiber strands (24), wherein the winding head (10) comprises at least two supply spools (16a, 16b, 16c) for receiving the same number of fiber strands (18a, 18b, 18c), and each supply spool (16a, 16b, 16c) is equipped with a guide roller (20a, 10b, 20c) and downstream of the guide roller (20a, 10b, 20c) there is provided a bundling roller (22) at a distance, wherein the fiber strands (18a, 18b, 18c) upstream of the impregnation unit (30) can be combined into a total fiber strand (24). In this way, components can be produced which can become more variable in their properties compared to conventional winding methods. Thus, fiber strands with different properties can be combined.

Description

Technical Field

[0001] This invention relates to a winding head for manufacturing fiber-reinforced components, wherein the fiber-reinforced components are manufactured by winding resin-impregnated fiber strands around a winding support. The winding head includes a supply spool for the fiber strands and an impregnation unit through which the fiber strands can be impregnated with liquid resin. The invention also relates to a winding method for manufacturing fiber-reinforced components using said winding head. Background Technology

[0002] A winding system is known from DE 10 2017 005 754 A1, in which a robotic arm with a winding head is used to receive an octagonal retainer surrounding eight winding supports. The winding supports are wound sequentially, and the robotic arm continues to rotate from one winding support to the next after completing one winding.

[0003] European patent application EP 0 491 354 A1 discloses a winding system for producing fiber-reinforced components with a tape lay-up head, in which a tape is pressed onto a core by rollers and then cured and hardened directly on-site to fix the fabric so that it cannot slip and remains in place.

[0004] US Patent Application US 2003 / 0186038 A1 discloses a composite material made of multiple thin ribbons. The ribbons are wound to form the composite material. The ribbons can be impregnated with a solid or semi-solid resin. The ribbons are wound in multiple directions to form a composite sheet. Furthermore, the composite material can be made to have a varying number of layers and fiber orientation throughout the composite sheet. In another embodiment, composite parts requiring multiple layers and fiber orientation can be manufactured essentially in a single filament winding process.

[0005] Typically, the winding operation is performed using fiber strands preferably composed of carbon fiber filaments. Summary of the Invention

[0006] The purpose of this invention is to provide a winding device or winding head and a winding method that enables more flexible production of fiber-reinforced components.

[0007] The object of the present invention is achieved by the following means: the winding head includes at least two supply spools for receiving two fiber strands, each supply spool is provided with a first guide roller, and a binding roller is provided at intervals downstream of the first guide roller, wherein, upstream of the impregnation unit, at least two fiber strands can be merged into a total fiber strand at the binding roller, and an extension roller is provided at intervals downstream of the binding roller for forming two fiber extension sections.

[0008] Compared to traditional winding methods, this approach allows for the production of components with more variable properties. Therefore, fiber strands with different properties can be combined, particularly carbon fiber strands and aramid fiber strands. The latter has better impact resistance than carbon fiber, resulting in components manufactured in this way with greater resistance in this regard. Carbon fiber or aramid fiber can be combined with actuator yarn and / or sensor yarn. The actuator can be a piezoelectric element or shape memory alloy. An electrical conductor or semiconductor with an external insulating layer can be used as the sensor fiber, with its ends connected to a measuring instrument. Extension rollers are spaced downstream of the bundling rollers to form two fiber extension segments. This provides longer extension segments and spacing for the fiber strands, allowing the width of the fiber strands to approximately double. This compensates for variations in the movement of the fiber strands on their respective supply spools.

[0009] Two or more fiber strands of the same material can also be combined to use fiber strands with a larger cross-section, thereby shortening the winding operation.

[0010] According to a favorable improvement, an extension roller with a deflection exceeding 150° is installed. This provides a longer extension section for the fiber strands, allowing the width of the fiber strands to approximately double. This compensates for the varying movement of the fiber strands on their respective supply spools.

[0011] According to a favorable improvement, cleaning brushes for removing fiber strand residue are installed at the bundling roller and / or the spreading roller, respectively. Fiber strands, composed of thousands of fiber filaments, often have broken filaments (fiber splices), which can be peeled off by the brushes.

[0012] According to an advantageous improvement, the impregnation unit has a mixing chamber in which at least one, preferably two or three turning points are provided for deflecting the total fiber strands. Through these guide rollers, the fiber strands are subjected to lateral forces, causing the filaments to move relative to each other, and the fiber strands to better penetrate the surrounding resin.

[0013] Preferably, the turning point is formed as a guide sleeve that is slidably supported on a pin. Therefore, after the mixing chamber is opened, the guide sleeve can be removed from the turning point to improve the cleaning operation.

[0014] According to an advantageous improvement, the winding head includes three supply spools for three fiber strands and three first deflection rollers, which are preferably arranged side by side or overlapping each other with rotation axes parallel to each other.

[0015] According to the advantageous improvement, the winding bracket is fixedly set, and the winding bracket to be wound is fixed on the robot with an articulated arm.

[0016] The object of the present invention is also achieved by a method for manufacturing a fiber-reinforced component by winding a support with resin-impregnated fiber strands, wherein the fiber strands are applied by a winding device, wherein at least two fiber strands are combined into a total fiber strand by a winding head, the total fiber strand is passed through an impregnation unit to mix in resin, and the total fiber strand is guided from the impregnation unit to the winding support.

[0017] According to the advantageous improvement scheme, at least one supply spool is equipped with carbon fiber. This type of fiber is characterized by high tear strength.

[0018] According to an advantageous improvement, at least one supply spool is equipped with an actuator yarn. Therefore, a variable-shape structure, such as a geometrically adjustable fin profile, can be achieved in the winding technology, its shape configuration advantageously changing according to inflow conditions. For example, the actuator yarn can be addressed / distinguished by applying voltage.

[0019] According to a favorable improvement scheme, at least one supply spool is equipped with a sensor yarn. Therefore, a so-called condition monitoring system (“system health monitoring or SHM system”) can be integrated into the structure, thereby enabling the monitoring of the stress state of components during operation.

[0020] According to the advantageous improvement scheme, at least one supply spool is equipped with aramid fiber. This type of fiber is characterized by high impact resistance. Attached Figure Description

[0021] Other advantages, features, and details are given in the following description, in which one embodiment is described in detail with reference to the accompanying drawings. Identical, similar, and / or functionally identical parts are labeled with the same reference numerals.

[0022] in:

[0023] Figure 1 A schematic side view of the winding device of the present invention is shown;

[0024] Figure 2 A perspective view of the impregnation unit in the open state is shown. Detailed Implementation

[0025] Figure 1A winding head 10, preferably connected to a robot with an articulated arm (not shown) to perform three-dimensional motion, is illustrated. The winding head winds resin-impregnated strands 14 of fiber flowing from a fiber storage tube 12 onto a winding support (not shown) to produce fiber-reinforced components. The entire system is preferably constructed as disclosed in DE 10 2017 005 754 A1. Alternatively, the winding head 10 can be kept fixed and the winding support moved by means of the robot with the articulated arm, as this depends only on the relative movement between the winding head 10 and the winding support. According to another alternative, both the winding head 10 and the winding support can be moved relative to each other by a suitable device having multiple translational and rotational degrees of freedom.

[0026] The winding head 10 shown includes three fiber supply spools 16a, 16b, and 16c, on which fiber strands 18a, 18b, and 18c, which may consist of thousands of filaments of the same or different materials, are wound, respectively. One fiber strand is preferably, but not necessarily, made of carbon, while the other fiber strand may be made of aramid fiber or also of carbon, or may be made of actuator yarn or sensor yarn. In other designs not shown, only two, four, or more of these supply spools may be provided instead of three fiber supply spools 16a, 16b, and 16c.

[0027] The winding head 10 also includes three guide rollers 20a, 20b, 20c loaded with three fiber strands 18a, 18b, 18c. The three fiber strands 18a, 18b, 18c are then loaded onto a binding roller 22, where they are combined and bundled into a total fiber strand 24. The total fiber strand 24 then travels to an extension roller 26 spaced from the binding roller 22, and from there to an optional inlet roller 28, and from there to an impregnation unit 30, in which it is impregnated or soaked with a curable resin. The resin-impregnated wound fiber strand 14 flows out of the impregnation unit 30 at the end of the fiber storage tube 12.

[0028] Between the binding roller 22 and the spreading roller 26, and between the spreading roller 26 and the guide roller 28, two spreading zones are defined for the total fiber strand 24, in which the total fiber strand 24 is spread to achieve better penetration with the resin in the impregnation unit 30.

[0029] Cleaning brushes 29 are provided at the binding roller 22, the extension roller 26 and the guide roller 28 respectively. The cleaning brushes clean these rollers by removing torn filaments during operation.

[0030] exist Figure 2The impregnation unit 30 in its open state is shown. The impregnation unit consists of two half-shells, with only the lower shell 32, fixed to the winding head 10, shown. Both half-shells have centering elements 34 and fixing holes 36 for fixing screws (not shown). The impregnation unit 30 has a mixing chamber 38 with an inlet channel 40 and an outlet channel 42. Curable resin is forced into the impregnation chamber 30 by a device (not shown). The end of the inlet channel 40 is provided with a seal 44, which allows passage from the total fiber strands 24 but prevents resin leakage. The mixing chamber 38 is surrounded by a sealing strip 46, which prevents resin leakage between the two half-shells. In the mixing chamber 38, three guide rollers 48 are arranged in a staggered manner, such that the total fiber strands 24 zig through the mixing chamber 38 to achieve the widest possible penetration or wetting with the resin. The guide rollers 48 are preferably constructed as sleeves held and guided on pins. Therefore, the guide rollers 48 can be cleaned by removing the sleeves in the disassembled state of the impregnation unit 30. An impregnation nozzle, not shown in detail, is screwed into the outlet channel 42, where only the screw attachment 50 is visible.

[0031] Although the invention has been described and explained in more detail through a preferred embodiment, the invention is not limited to the disclosed examples, and other variations can be derived by those skilled in the art without departing from the scope of protection of the invention. Therefore, it is apparent that numerous variations are possible. It is also clear that the above embodiments are merely illustrative examples and should not be construed in any way as limiting, for example, the scope of protection, applicability, or configuration of the invention. Rather, the foregoing description and accompanying drawings enable those skilled in the art to practice the exemplary embodiments in a specific manner, wherein various changes can be made by those skilled in the art, recognizing the disclosed inventive concept, such as changes in the function or arrangement of the various elements described in the exemplary embodiments, without departing from the scope of protection defined by the claims and their legal equivalents (as further explained in the description).

Claims

1. A winding head for a winding apparatus for manufacturing fiber-reinforced components, wherein the fiber-reinforced components are manufactured by winding a winding support with resin-impregnated fiber strands, the winding head (10) comprising at least two supply spools (16a, 16b, 16c) for receiving the same number of fiber strands (18a, 18b, 18c), and including an impregnation unit (30) through which the fiber strands (18a, 18b, 18c) can be impregnated with liquid resin; in, Each supply spool (16a, 16b, 16c) is equipped with guide rollers (20a, 20b, 20c), and a binding roller (22) is spaced downstream of the guide rollers (20a, 20b, 20c). Upstream of the impregnation unit (30), the fiber strands (18a, 18b, 18c) can be combined into a total fiber strand (24) at the binding roller. Downstream of the binding roller (22), an extension roller (26) is spaced to form two fiber extension segments, thereby providing extension segments and spacing for the fiber strands, wherein the width of the fiber strands is doubled to compensate for the varying movement of the fiber strands on their respective supply spools. The impregnation unit consists of two half-shells having a centering element (34) and a fixing hole (36), and is equipped with a guide roller for deflecting the total fiber strand (24), which is configured as a guide sleeve slidably supported on a pin.

2. The winding head according to claim 1, characterized in that, A cleaning brush (29) is provided at the binding roller (22) and / or the extension roller respectively.

3. The winding head according to any one of the preceding claims, characterized in that, The impregnation unit (30) has a mixing chamber (38) in which at least one guide roller for deflecting the total fiber strands (24) is provided.

4. The winding head according to claim 3, characterized in that, Two or three guide rollers are provided in the mixing chamber for deflecting the total fiber strands (24).

5. The winding head according to any one of the preceding claims, characterized in that, The winding head includes three supply spools (16a, 16b, 16c) for three fiber strands (18a, 18b, 18c) and three first deflection coils.

6. The winding head according to any one of the preceding claims, characterized in that, The winding bracket is fixedly installed, and the winding bracket to be wound is fixed on the robot with the articulated arm.

7. A method for manufacturing a fiber-reinforced member according to any one of the preceding claims by winding a support with resin-impregnated fiber strands, wherein the fiber strands are applied by a winding head (10); Its features are, At least two fiber strands (18a, 18b, 18c) are combined into a total fiber strand (24) by the winding head (10), and the total fiber strand (24) is passed through the binding roller (22) and the extension roller (26) disposed downstream of the binding roller (22) to form two fiber extension segments; and the total fiber strand is passed through the impregnation unit (30) to be mixed with resin; and the total fiber strand is guided from the impregnation unit to the winding support.

8. The method according to claim 7, characterized in that, At least one of the supply spools (16a, 16b, 16c) is equipped with carbon fiber and / or aramid fiber.

9. The method according to claim 7 or 8, characterized in that, At least one of the supply spools (16a, 16b, 16c) is equipped with actuator yarn or sensor yarn.

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