SYSTEMS FOR AND METHODS OF FORMING STRUCTURAL COMPONENTS

Abstract

Systems for and methods of forming structural components from a source, such as one or more rolls, of a fibrous material (e.g., fabric) are disclosed. The fibrous material is made up of multiple layers, with at least one pair of adjacent layers having different lengths.

Claims

1. A method of producing a structural component formed by molding a plurality of layers of a fiber reinforced material, the method comprising: providing a roll of the fiber reinforced material, wherein the roll includes a plurality of layers of the fiber reinforced material; removing a first length of the fiber reinforced material from the roll, the first length including a first layer of the fiber reinforced material and a second layer of the fiber reinforced material, wherein the first layer is adjacent to the second layer, and wherein a length of the first layer differs from a length of the second layer to form a first offset; and positioning the first length of the fiber reinforced material in a mold so that the first offset is at a desired location, thereby simultaneously positioning the first layer and the second layer in the mold.

2. The method of claim 1, further comprising: introducing a resin into the mold; and curing the resin to form the structural component.

3. The method of claim 2, further comprising: removing a second length of the fiber reinforced material from the roll, the second length including a third layer of the fiber reinforced material and a fourth layer of the fiber reinforced material, wherein the third layer is adjacent to the fourth layer, and wherein a length of the third layer differs from a length of the fourth layer to form a second offset; and positioning the second length of the fiber reinforced material in the mold so that the second offset is at a desired location, thereby simultaneously positioning the third layer and the fourth layer in the mold.

4. The method of claim 3, wherein the first length is adjacent to the second length in the mold.

5. The method of claim 3, wherein the length of the first layer differs from the length of the third layer.

6. The method of claim 3, wherein the length of the second layer differs from the length of the fourth layer.

7. The method of claim 1, wherein the roll comprises 3 to 10 layers of the fiber reinforced material.

8. The method of claim 1, wherein the roll comprises at least 4 layers of the fiber reinforced material.

9. The method of claim 1, wherein the first layer is fixed to the second layer on the roll.

10. The method of claim 9, wherein the first layer is fixed to the second layer by an adhesive.

11. The method of claim 9, wherein the first layer is fixed to the second layer by stitching.

12. The method of claim 9, wherein the first layer is fixed to the second layer by at least one removable clip.

13. The method of claim 3, wherein the third layer is fixed to the fourth layer on the roll.

14. The method of claim 13, wherein the third layer is fixed to the fourth layer by an adhesive.

15. The method of claim 13, wherein the third layer is fixed to the fourth layer by stitching.

16. The method of claim 13, wherein the third layer is fixed to the fourth layer by at least one removable clip.

17. The method of claim 1, wherein the structural component is a spar cap.

18. The method of claim 1, wherein the fiber reinforced material includes at least one of glass fibers and carbon fibers.

19. The method of claim 1, wherein the structural component is formed from a plurality of rolls of the fiber reinforced material.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0041] The general inventive concepts, as well as embodiments and advantages thereof, are described below in greater detail, by way of example, with reference to the drawings in which:

[0042] FIG. 1 is a diagram of a conventional system for forming a woven fabric.

[0043] FIG. 2 is a diagram of rolls of the woven fabric produced by the system of FIG. 1.

[0044] FIG. 3 is a diagram showing use of the rolls of FIG. 2 during production of the spar cap.

[0045] FIGS. 4A and 4B illustrate a conventional technique for forming a spar cap from a roll of fiber reinforced material. FIG. 4A is a diagram showing separation of discrete pieces from the roll of fiber reinforced material. FIG. 4B is a diagram showing placement of the pieces of FIG. 4A into a mold for forming the spar cap.

[0046] FIGS. 5A, 5B, and 5C illustrate a technique for forming a spar cap from a roll of fiber reinforced material, according to an exemplary embodiment. FIG. 5A is a diagram showing separation of a fabric stack from the roll of fiber reinforced material. FIG. 5B is a detailed view of a section of the fabric stack of FIG. 5A. FIG. 5C is a diagram showing placement of the fabric stack of FIG. 5A into a mold for forming the spar cap.

[0047] FIG. 6 is a diagram showing production of a fabric stack, according to an exemplary embodiment.

[0048] FIGS. 7A and 7B illustrate separation of different fabric stacks from a roll of fiber reinforced material, according to an exemplary embodiment. FIG. 7A is a side elevational view of two fabric stacks after separation from the roll. FIG. 7B is a top plan view of the two fabric stacks prior to separation from the roll.

DETAILED DESCRIPTION

[0049] While the general inventive concepts are susceptible of embodiment in many different forms, there are shown in the drawings, and will be described herein in detail, specific embodiments thereof with the understanding that the present disclosure is to be considered as an exemplification of the principles of the general inventive concepts. Accordingly, the general inventive concepts are not intended to be limited to the specific embodiments illustrated herein.

[0050] The general inventive concepts encompass systems for and methods of forming structural components from layers of a fiber reinforced material obtained from a source of the material. While the exemplary embodiments described herein disclose one or more rolls as the source of the fiber reinforced material, the general inventive concepts encompass other means of making, storing, and transporting the fiber reinforced material that do not involve rolling the fiber reinforced material into a roll. For example, the fiber reinforced material could be stacked on a pallet, folded in a box, etc.

[0051] A conventional system 200 for forming a structural component (e.g., a spar cap) will be described with reference to FIGS. 4A and 4B. In the system 200, a roll 202 of a fiber reinforced material (e.g., the fabric 104) for forming the spar cap is provided.

[0052] A first portion 204 of the fiber reinforced material is unrolled and cut (indicated by dashed line 206) from the roll 202. Assume this processing takes a certain amount of time t.sub.1.

[0053] The first portion 204 of the fiber reinforced material is then placed in a mold 220 and positioned according to a design specification for the spar cap. This processing takes a certain amount of time t.sub.2.

[0054] Next, a second portion 208 of the fiber reinforced material is unrolled and cut (indicated by dashed line 210) from the roll 202. This processing takes a certain amount of time t.sub.3.

[0055] The second portion 208 of the fiber reinforced material is then placed in the mold 220 and positioned relative to the first portion 204 of the fiber reinforced material according to the design specification for the spar cap. This processing takes a certain amount of time t.sub.4.

[0056] Finally, a third portion 212 of the fiber reinforced material is unrolled and cut (indicated by dashed line 214) from the roll 202. This processing takes a certain amount of time t.sub.5.

[0057] The third portion 212 of the fiber reinforced material is then placed in the mold 220 and positioned relative to the first portion 204 and the second portion 208 of the fiber reinforced material according to the design specification for the spar cap. This processing takes a certain amount of time t.sub.6.

[0058] For simplicity's sake, assuming the spar cap is constructed from only the first, second, and third portions 204, 208, 212 of the fiber reinforced material, then the total processing time for forming the spar cap (without taking into account the time for introducing the resin into the mold and curing same) can be represented as: t.sub.total=t.sub.1+t.sub.2+t.sub.3+t.sub.4+t.sub.5+t.sub.6.

[0059] As can be seen, this total processing time (t.sub.total) for forming the spar cap will increase as the number of portions (i.e., layers) of the fiber reinforced material needed to be cut from the roll 202 and placed in the mold 220 increases.

[0060] As noted above, it is not uncommon for spar caps to require many (e.g., 50 or more) discrete pieces of the fiber reinforced material to be layered (e.g., hand laid) into the mold 220. Typically, many (if not all) of the pieces cut from the roll 202 will vary in length. The number and placement of the cut pieces within the mold 220 define the properties (e.g., shape, thickness) of the spar cap.

[0061] In the example shown in FIGS. 4A and 4B, the first portion 204 of the fiber reinforced material has a length L.sub.1, the second portion 208 of the fiber reinforced material has a length L.sub.2, and the third portion 212 of the fiber reinforced material has a length L.sub.3, wherein L.sub.3>L.sub.2>L.sub.1.

[0062] A system 300 for forming a structural component (e.g., a spar cap), according to an exemplary embodiment of the invention, will be described with reference to FIGS. 5A, 5B, and 5C. In the system 300, a roll 302 of a fiber reinforced material for forming the spar cap is provided. In this case, the fiber reinforced material is a fabric stack 304 comprising multiple discrete layers of the fiber reinforced material, wherein at least one pair of adjacent layers on the roll 302 has different lengths.

[0063] A portion of the fabric stack 304 is unrolled and cut (indicated by dashed line 306) from the roll 302. Assume this processing takes a certain amount of time t.sub.7.

[0064] The portion of the fabric stack 304 is then placed in a mold 320 and positioned according to a design specification for the spar cap. This processing takes a certain amount of time t.sub.8.

[0065] As shown in detail z of FIG. 5B, the portion of the fabric stack 304 includes three discrete layers, i.e., a first layer 308, a second layer 310, and a third layer 312. To facilitate a comparison, the first layer 308 of the fabric stack 304 has approximately the same make-up as the first portion 204 of the fiber reinforced material (including a length L.sub.1), the second layer 310 of the fabric stack 304 has approximately the same make-up as the second portion 208 of the fiber reinforced material (including a length L.sub.2), and the third layer 312 of the fabric stack 304 has approximately the same make-up as the third portion 212 of the fiber reinforced material (including a length L.sub.3).

[0066] For simplicity's sake, assuming the spar cap is constructed from only the single portion of the fabric stack 304 unrolled and cut from the roll 302, then the total processing time for forming the spar cap (without taking into account the time for introducing the resin into the mold and curing same) can be represented as: t.sub.total=t.sub.7+t.sub.8. This is because the individual layers 308, 310, 312 are already positioned relative to one another on the roll 302 based on their intended positioning relative to one another in the mold 320 in accordance with the design specification for the spar cap.

[0067] Thus, treating the time t.sub.7 to be approximately equal to the time t.sub.1 and the time t.sub.8 to be approximately equal to the time t.sub.2, the total processing time of the system 300 is significantly reduced (e.g., by approximately t.sub.3+t.sub.4+t.sub.5+t.sub.6) compared to the total processing time of the conventional system 200. This processing time savings would be expected to further increase as the number of layers forming the fabric stack 304 on the roll 302 increases.

[0068] As noted above, the multiple layers (e.g., layers 308, 310, 312) in the fabric stack 304 are positioned relative to one another on the roll 302 based on their intended positioning relative to one another in the mold 320, according to a design specification for the structural component being molded.

[0069] In some exemplary embodiments, the relative positioning of the layers in the fabric stack 304 is maintained simply by the rolling process (see FIG. 6).

[0070] In some exemplary embodiments, means for affixing the layers to one another could be used. Such affixing means might be used to prevent undesired movement of the layers relative to one another, such as during the rolling process or subsequent downstream handling of the fiber reinforced material (e.g., placement of the fabric stack 304 in the mold 320). The affixing means might also be effective in preventing wrinkles or like from forming in the fabric stack 304, as such wrinkles could introduce flaws in the molded structural component or otherwise require added production time to remove the wrinkles by hand.

[0071] Any means suitable for maintaining the relative positioning of each layer of fiber reinforced material in the fabric stack 304 could be used. In some exemplary embodiments, the affixing means is an adhesive. In some exemplary embodiments, the affixing means is a binder. In some exemplary embodiments, the affixing means involves mechanical entanglement (e.g., needling) of the layers. In some exemplary embodiments, the affixing means involves stitching the layers together. In some exemplary embodiments, the affixing means may be a temporary means of holding the layers in the fabric stack 304 together, such as removable clamps, clips, or the like.

[0072] A system 400 for producing the roll 302 of the fabric stack 304, according to an exemplary embodiment, is shown in FIG. 6.

[0073] Since the fabric stack 304 is made up of the first layer 308, the second layer 310, and the third layer 312 of the fiber reinforced material, the system 400 utilizes a first supply roll 402, a second supply roll 404, and a third supply roll 406 of the fiber reinforced material. A rack 410 or other structure for holding the supply rolls 402, 404, 406 is mounted on a frame 412 or other support structure (e.g., floor).

[0074] The fiber reinforced material is simultaneously unrolled from the supply rolls 402, 404, 406 to form the fabric stack 304. In particular, a first portion of the fabric stack 304 includes a first layer 420 of the fiber reinforced material having the length L.sub.1, a second layer 422 of the fiber reinforced material having the length L.sub.2, and a third layer 424 of the fiber reinforced material having the length L.sub.3, which are fed to a winder 414 that winds the layers 420, 422, 424 into the roll 302. As noted above, L.sub.3>L.sub.2>L.sub.1. In other words, the first layer 420 is offset from the second layer 422 by a length 430, while the second layer 422 is offset from the third layer 424 by a length 432, during winding of the layers 420, 422, 424 by the winder 414. These offset lengths can be repeated and/or varied for other portions of the fabric stack 304 on the roll 302.

[0075] By using a fabric stack (e.g., the fabric stack 304), as described herein, a spar cap or other molded structural component can generally be formed more quickly and in a less labor-intensive manner (providing a cost benefit). For example, a spar cap can be formed by layering, such as by hand laying, one or more portions of the fabric stack into a mold. The number of layers in each portion of the fabric stack and the relative offset lengths between the layers will correspond to the positioning of the individual layers of fiber reinforced material in the mold, thereby defining the properties (e.g., shape, thickness) of the spar cap.

[0076] In one exemplary embodiment, a system 700 for producing a structural component formed by molding a plurality of layers of a fiber reinforced material 702 comprises a roll 704 of the fiber reinforced material 702, wherein the roll 704 includes a plurality of distinct layers of the fiber reinforced material 702, as shown in FIGS. 7A and 7B. The roll includes a first indicia 710 of where to cut 712 the roll 704 to form a first length 714 of the fiber reinforced material 702. The roll includes a second indicia 730 of where to cut 732 the roll 704 to form a second length 734 of the fiber reinforced material 702. The first length 714 and the second length 734 can readily differ based on placement of the indicia 710, 730 on the fiber reinforced material 702, prior to rolling on the roll 704. The first indicia 710 and the second indicia 730 (see FIG. 7B) can be any suitable marking (e.g., a printed line) that allows a human or machine to readily determine where to separate a portion of the fiber reinforced material 702 from the roll 704.

[0077] The first length 714 includes a first layer 716 of the fiber reinforced material 702 and a second layer 718 of the fiber reinforced material 702, wherein the two layers 716, 718 are in contact with one another or otherwise adjacent to one another. The second length 734 includes a third layer 736 of the fiber reinforced material 702 and a fourth layer 738 of the fiber reinforced material 702, wherein the two layers 736, 738 are in contact with one another or otherwise adjacent to one another. A length of the first layer 716 will typically be equal to the first length 714. A length of the first layer 716 differs from a length of the second layer 718 to form a first offset 720. A length of the third layer 736 will typically be equal to the second length 734. A length of the third layer 736 differs from a length of the fourth layer 738 to form a second offset 740.

[0078] The first offset 720 corresponds to the desired positioning of the first layer 716 relative to the second layer 718 in a mold, while the second offset 740 corresponds to the desired positioning of the third layer 736 relative to the fourth layer 738 in the mold. It will be appreciated that the first length 714 of the fiber reinforced material 702 and the second length 734 of the fiber reinforced material 702 could be placed in the mold in any order, whether adjacent to one another or not, depending on the structural component being formed. In some exemplary embodiments, to increase overall efficiency, the lengths (e.g., lengths 714, 734) of the fiber reinforced material 702 are removed from the roll 704 in the order in which they are to be placed into the mold.

[0079] In some exemplary embodiments, a thickness of each distinct layer (e.g., the layers 716, 718, 736, 738) is the same. In some exemplary embodiments, a length of the first layer 716 differs from a length of the second layer 718, the third layer 736, and the fourth layer 738. In some exemplary embodiments, a length of the second layer 718 differs from a length of the first layer 716, the third layer 736, and the fourth layer 738. In some exemplary embodiments, a length of the third layer 736 differs from a length of the first layer 716, the second layer 718, and the fourth layer 738. In some exemplary embodiments, a length of the fourth layer 738 differs from a length of the first layer 716, the second layer 718, and the third layer 736.

[0080] It will be appreciated that the scope of the general inventive concepts is not intended to be limited to the particular exemplary embodiments shown and described herein. From the disclosure given, those skilled in the art will not only understand the general inventive concepts and their attendant advantages, but will also find apparent various changes and modifications to the systems and methods disclosed. For example, while various exemplary embodiments are described herein as having a multi-layer roll of reinforcement material wherein a length of adjacent layers differ in length, the layers can also differ by other properties (e.g., width, thickness, weight, composition, etc.). As another example, while the exemplary embodiments shown and described herein illustrate a fabric stack including three distinct layers, the general inventive concepts are not so limited and instead contemplate fabric stacks that can have more or fewer total layers. It is sought, therefore, to cover all such changes and modifications as fall within the spirit and scope of the general inventive concepts, as described and claimed herein, and any equivalents thereof.