WO2023199333A1

WO2023199333A1 - Composite body panels

Info

Publication number: WO2023199333A1
Application number: PCT/IN2022/050583
Authority: WO
Inventors: Shashank Kumar Singh Deo; Sandeep Sharma; Inderveer Singh Panesar; Tejveer Singh
Original assignee: Evage Ventures Pvt. Ltd.
Priority date: 2022-04-11
Filing date: 2022-06-25
Publication date: 2023-10-19

Abstract

A composite body panel (500) is disclosed. The composite body panel (500) includes a plurality of layers (102) of composite fiber and a plurality of epoxy-based layers (104). The plurality of layers (102) of the composite fiber and the plurality of epoxy-based layers (104) are alternatively positioned in a sandwiching formation to form the body panel (500). The composite body panel (500) also includes a laminate coating of predefined thickness formed across the surface of each of the plurality of the layers (102) of the composite fiber to facilitate multiaxial loading of the composite body panel (500).

Description

FIELD OF THE INVENTION

[001] The present disclosure relates to composite-based panels and particularly to composite body panels for a vehicle and a method of forming such composite body panels by a moulding technique.

BACKGROUND

[002] In the automotive industry, the usual practice to manufacture body panels of a vehicle goes through a lot of design challenges and associated complications. First and foremost, the starting cost of manufacturing the body panels by the existing techniques is significantly high. As is generally known, door beams, roof, and most of the body panels of a vehicle nowadays are made up of steel. Therefore, tooling cost, labor cost, equipment cost, and dye cost lead to high production costs of the sheet metal process for developing the body panels.

[003] Further, owing to the high density of metal, the weight of the body panels so formed is high, leading to a high overall weight of the vehicle. Another example of downside of heavy weight body panels can also be observed in form of door sagging, which often happens due to the load acting downwards on the vehicle door due to its self-weight. Considering that the weight plays a major role in terms of performance and milage, particularly, for electric vehicles, the use of steel for making the body panels is therefore not a preferred proposition anymore.

[004] Moreover, sheet metals generally include grains that are crucial in deciding various associated properties. For example, load and stress flow in the sheet metals is often unidirectional due to the grain structure. Furthermore, the material grade used for making the body panels for a vehicle have bigger grain size, which results in weaker parts. On the other hand, adjusting grain size to be within a beneficial range can be done after the rolling is done during the sheet metal process but it requires additional processes, such as annealing, which further adds to time, equipment, and the cost of manufacturing the body panels. [005] In addition, the existing body panels, say, body panels extracted out of a dye are integrated with other body panels on the vehicle using a welding process. The welding process is known to reduce the stress load capacity of the part at the welded region and significantly adds to an overall cost of the manufacturing of the body panels.

[006] Therefore, the existing body panels and the associated process of manufacturing are ineffective, inconvenient, time-intensive, complicated, and expensive.

SUMMARY

[007] This summary is provided to introduce a selection of concepts, in a simplified format, that are further described in the detailed description of the invention. This summary is neither intended to identify key or essential inventive concepts of the invention and nor is it intended for determining the scope of the invention.

[008] In an implementation of the present disclosure, a composite body panel is disclosed. The composite body panel includes a plurality of layers of composite fiber and a plurality of epoxy -based layers. The plurality of layers of the composite fiber and the plurality of epoxy-based layers are alternatively positioned in a sandwiching formation to form the body panel. The composite body panel includes a laminate coating of predefined thickness formed across the surface of each of the plurality of the layers of the composite fiber to facilitate multiaxial loading of the composite body panel.

[009] In another implementation of the present disclosure, a method of forming a composite body panel by a moulding technique is disclosed. The method includes placing a plurality of layers of composite fibers in a pattern-shaped mould and placing a plurality of epoxy -based layers in the mould. The plurality of layers of the composite fiber and the plurality of epoxy-based layers are alternatively positioned in a sandwiching formation in the mould. The method includes adding a hardener material to a slurry formed by melting of the plurality of layers of the composite fibers and the plurality of epoxy -based layers in the mould. The method also includes extracting the composite body panel from the mould, after solidification and cooling of the hardener-infused slurry

[010] In another implementation of the present disclosure, an electric vehicle includes at least one composite body panel. The composite body panel includes a plurality of layers of composite fiber and a plurality of epoxy-based layers. The plurality of layers of the composite fiber and the plurality of epoxy -based layers are alternatively positioned in a sandwiching formation to form the composite body panel. The composite body panel also includes a laminate coating of predefined thickness formed across the surface of each of the plurality of the layers of the composite fiber to facilitate multiaxial loading for the composite body panel.

[OH] To further clarify the advantages and features of the present invention, a more particular description of the invention will be rendered by reference to specific implementations thereof, which is illustrated in the appended drawings. It is appreciated that these drawings depict only typical implementations of the invention and are therefore not to be considered limiting of its scope. The invention will be described and explained with additional specificity and detail with the accompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

[012] These and other features, aspects, and advantages of the present invention will become better understood when the following detailed description is read with reference to the accompanying drawings in which like characters represent like parts throughout the drawings, wherein:

[013] Figure 1 illustrates a schematic view depicting various layers of a composite body panel being placed in a mould, according to an implementation of the present disclosure; [014] Figure 2 illustrates a bi-directional weave structure of a layer of composite fiber of the composite body panel, according to an implementation of the present disclosure;

[015] Figure 3 illustrates a multi-directional weave structure of a layer of composite fiber of the composite body panel, according to an implementation of the present disclosure;

[016] Figure 4 illustrates a method of forming the composite body panel by a moulding technique, according to an implementation of the present disclosure;

[017] Figure 5 illustrates an example composite body panel, according to an implementation of the present disclosure; and

[018] Figure 6 illustrates a side view of a vehicle having composite body panels, according to an implementation of the present disclosure.

[019] Further, skilled artisans will appreciate that elements in the drawings are illustrated for simplicity and may not have necessarily been drawn to scale. For example, the flow charts illustrate the method in terms of the most prominent steps involved to help to improve understanding of aspects of the present invention. Furthermore, in terms of the construction of the device, one or more components of the device may have been represented in the drawings by conventional symbols, and the drawings may show only those specific details that are pertinent to understanding the implementations of the present invention so as not to obscure the drawings with details that will be readily apparent to those of ordinary skill in the art having benefit of the description herein.

DETAILED DESCRIPTION OF FIGURES

[020] For the purpose of promoting an understanding of the principles of the invention, reference will now be made to the implementation illustrated in the drawings and specific language will be used to describe the same. It will nevertheless be understood that no limitation of the scope of the invention is thereby intended, such alterations and further modifications in the illustrated system, and such further applications of the principles of the invention as illustrated therein being contemplated as would normally occur to one skilled in the art to which the invention relates. Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skilled in the art to which this invention belongs. The system, methods, and examples provided herein are illustrative only and not intended to be limiting.

[021] Whether or not a certain feature or element was limited to being used only once, it may still be referred to as “one or more features” or “one or more elements” or “at least one feature” or “at least one element.” Furthermore, the use of the terms “one or more” or “at least one” feature or element do not preclude there being none of that feature or element, unless otherwise specified by limiting language including, but not limited to, “there needs to be one or more...” or “one or more element is required.”

[022] Unless otherwise defined, all terms and especially any technical and/or scientific terms, used herein may be taken to have the same meaning as commonly understood by a person ordinarily skilled in the art.

[023] Reference is made herein to some “implementations.” It should be understood that an implementation is an example of a possible implementation of any features and/or elements of the present disclosure. Some implementations have been described for the purpose of explaining one or more of the potential ways in which the specific features and/or elements of the proposed disclosure fulfil the requirements of uniqueness, utility, and non-obviousness.

[024] Use of the phrases and/or terms including, but not limited to, “a first implementation,” “a further implementation,” “an alternate implementation,” “one implementation,” “an implementation,” “multiple implementations,” “some implementations,” “other implementations,” “further implementation”, “furthermore implementation”, “additional implementation” or other variants thereof do not necessarily refer to the same implementations. Unless otherwise specified, one or more particular features and/or elements described in connection with one or more implementations may be found in one implementation, or may be found in more than one implementation, or may be found in all implementations, or may be found in no implementations. Although one or more features and/or elements may be described herein in the context of only a single implementation, or in the context of more than one implementation, or in the context of all implementations, the features and/or elements may instead be provided separately or in any appropriate combination or not at all. Conversely, any features and/or elements described in the context of separate implementations may alternatively be realized as existing together in the context of a single implementation.

[025] Any particular and all details set forth herein are used in the context of some implementations and therefore should not necessarily be taken as limiting factors to the proposed disclosure.

[026] In the present invention, unlike the usual practice of making body panels with sheet metals, Composite is used for the same purpose, owing at least to the various associated advantages. For example, composites are both light weight and strong. They offer better strength to weight ratio, much greater than those of other materials.

[027] One of the objectives of the present invention is to design and manufacture a body panel for an electric vehicle using composite, which is lightweight and has better load bearing capacity. The use of composite for the body panels also significantly reduces the associated processes and time taken for manufacturing.

[028] Another objective is to keep the weight of the body panel as low as possible with strength criteria met.

[029] Implementations of the present invention will now be described below in detail with reference to the accompanying drawings. [030] Figure 1 illustrates a schematic view depicting various layers of a composite body panel (shown in Figure 5) being placed in a mould 100, according to an implementation of the present disclosure. In an implementation, the composite body panel is for installation in a vehicle. In another implementation, the composite body panel is for installation in an electric vehicle.

[031] In an implementation, the composite body panel may be formed by a moulding technique. The process of forming the composite body panel through the moulding technique is explained in detail in the description of Figure 4.

[032] In an implementation, the composite body panel may include, but is not limited to, a plurality of layers 102 of composite fiber and a plurality of epoxybased layers 104. For the sake of readability, the plurality of layers 102 and the plurality of epoxy -based layers 104 are hereinafter interchangeably referred to as the layers 102 and the epoxy -based layers 104, respectively.

[033] In an implementation, the composite fiber of the layers 102 may be Fiber Reinforced Polymer (FRP). FRP is 70% lighter than the steel used in the manufacturing of existing body panels and even 40% lighter than the aluminium used in the structure of the aircrafts. Further, metallurgic configuration of FRP includes chemical resistance inside the matter which makes the material even tougher. This chemical composition is also a reason of high performance at elevated temperatures.

[034] Furthermore, FRP being non-metallic in nature cannot be welded onto any structure, which makes it safe from the repercussions of welding. This is beneficial particularly in the application of vehicles where multiple body panels are to be connected to form the body framework. Moreover, in case of FRP being used for the formation of the composite body panels, the load distribution is not unidirectional. In fact, the composite body panel of the present invention exhibits uniform distribution of load and stresses in all direction, unlike sheet metal structure of grains of the existing body panels. [035] Further, in an implementation, the epoxy resin in each of the epoxybased layers 104 is BiSphenol A Epoxy Resin (DGEBA).

Bisphenol A Epoxy Resin (DGEBA)

[036] In the illustrated implementation, the composite body panel is shown to be formed of two layers 102 of composite fiber and two epoxy -based layers 104. The layers 102 are individually referred to as 102-1 and 102-2. Further, the epoxybased layers 104 are individually referred to as 104-1 and 104-2. As would be appreciated by a person skilled in the art, the number of layers 102 of the composite fiber and the number of epoxy -based layers 104 may vary in other implementations, without departing from the scope of the present disclosure. For example, in other implementations, the number of layers 102, 104 may be less or more than the number shown in the illustrated implementation, say, based on the desired properties of the composite body panel. Therefore, the number of layers 102, 104 shown in the illustrated implementation should not be construed as limiting the scope of the invention in any way.

[037] Further, the layers 102 of the composite fiber and the epoxy -based layers 104 may be alternatively positioned in a sandwiching formation to form the composite body panel. As shown, in the illustrated implementation, the layer 102- 1 is positioned between the epoxy -based layer 104-1 and the epoxy -based layer 104-2. Similarly, the epoxy -based layer 104-2 is positioned between the layer 102- 1 and the layer 102-2. Therefore, the layers 102 and the epoxy -based layers 104 are positioned in the sandwiching formation. [038] Further, each of the layers 102 of the composite fiber includes either bidirectional weaves or multi-directional weaves. In an implementation, the weight of the weaves in the composite fiber is within a range of 350 Grams per Square Meter (GSM) to 450 GSM. The fiber pattern and the structure of the layers 102 play a crucial role in deciding the impact bearing capabilities of the composite body panel so formed.

[039] Figure 2 illustrates a bi-directional weave structure of a layer 102 of the composite fiber of the composite body panel, according to an implementation of the present disclosure. The illustrated implementation shows the bi-directional weave of about 350 GSM of the composite fiber of the layer 102.

[040] Figure 3 illustrates a multi-directional weave structure of the layer 102 of composite fiber of the composite body panel, according to an implementation of the present disclosure. The illustrated implementation shows the multi-directional weave of about 300 GSM of the composite fiber of the layer 102.

[041] In an implementation, a combination of the bi-directional weave structure and the multi-directional weave structure in the layer 102 of the composite fiber is used for making the body panels. This would provide the required stiffness, toughness, and strength to the composite body panels so formed.

[042] Referring to Figure 1, in an implementation, the composite body panel may also include a hardener material such that an epoxy-to-hardener ratio in the composite body panel is of 2: 1. In an implementation, using a 2: 1 epoxy-to- hardener ratio with weave from 350GSM to 450GSM, load bearing capacity of more than 10 times the weight of the composite body panel may be achieved. The load bearing capacity may also depend on the dimensions of the composite body panel. In an implementation, the hardener material may include, but is not limited to, AH365 and AH367.

[043] In an implementation, the composite body panel may further include a laminate coating of predefined thickness formed across the surface of each of the layers 102 of the composite fiber to facilitate multiaxial loading of the composite body panel. The provision of the laminate coating in the composite body panel further strengthens the material and helps the structure to bear heavier load/impact. In other words, the composite body panel of the present disclosure exhibits high Flexural Modulus to carry heavier impacts/loads. In an implementation, the thickness of the laminate coating may be within a range of 0.5 mm to 2.5 mm.

[044] In an implementation, the directional nature of the load paths requires the inertia to be such that spots experiencing stresses greater than the surroundings require greater inertia to withstand the bending moment being generated at those spots. The solution is to increase the thickness at those spots or regions. Therefore, in an implementation, the composite body panel may be formed such that a thickness of a layer 102 of the composite fiber, amongst the layers 102 of the composite fiber, is more at a spot experiencing greater stresses than the surroundings. This would ensure that the spots expected to experience greater stresses are capable of bearing the stress without any possibility of a failure.

[045] Figure 4 illustrates a method 400 of forming the composite body panel by a moulding technique, according to an implementation of the present disclosure. For the sake of brevity, the constructional and operational features of the composite body panel that are already disclosed in detail in the description of Figure 1 to Figure 3 are not discussed in the description of Figure 4.

[046] First, a mould 100 is prepared of a predefined shape, based on desired dimensions of the composite body panel. Further, a pattern corresponding to the shape of the composite body panel is prepared, which is to be positioned in the mould 100 to give it the desired shape of the body panel such that when the layers 102, 104 are solidified in the mould 100, the composite body panel of the desired shape can be extracted.

[047] At a block 402, the method 400 includes placing the layers 102 of composite fibers in the pattern-shaped mould 100. In an implementation, the method 400 may include placing each of the layers 102 of the composite fibers such that a direction of the constituent fibers is predefined to achieve maximum strength of the formed composite body panel. This would improve multiaxial loading potential of the composite body panel so formed, thus making it an impact resistant material. The lesser number of free electrons in this composition makes the composite body panel, highly resistive to electricity, thus making it highly suitable for the application in electric vehicle.

[048] At a block 404, the method 400 includes placing the epoxy -based layers 104 in the mould 100. The layers 102 of the composite fiber and the epoxy -based layers 104 are alternatively positioned in a sandwiching formation in the mould 100. At a block 406, the method 400 includes adding the hardener material to a slurry formed by melting of the layers 102 of the composite fibers and the epoxybased layers 104 in the mould 100. At a block 408, the method 400 includes extracting the composite body panel from the mould 100, after solidification and cooling of the hardener-infused slurry.

[049] Figure 5 illustrates an example composite body panel 500, according to an implementation of the present disclosure. Therefore, the composite body panel 500 is formed by the method 400 and is formed of the layers 102 of composite fibers, the epoxy -based layers 104, the hardener material, and the laminate coating. In an implementation, the dimension of the composite body panel 500 is 1220mm x 3750 mm.

[050] Figure 6 illustrates a side view of a vehicle 600 having a composite body panel 500 integrated of multiple body panels, according to an implementation of the present disclosure. For example, the illustrated implementation shows the vehicle 600 having the composite body panel 500 integrated of a side body panel, a front facial body panel , side skirts, and a bumper made by the method 400 of the present disclosure.

[051] As would be gathered, the present disclosure offers the composite body panel 500 that provides optimum strength to weight ratio. The offered ratio is significantly better that the conventional steel being used worldwide for body work in the automobile industry. Further, the use of composite fibers in the composite body panel 500 would provide corrosion resistance, which in turn eliminates the requirement of frequent maintenance of the panels 500.

[052] Furthermore, the use of composite over sheet metal for the manufacturing of the body panels 500 reduces the number of operations used in the assembly line to obtain the finished part. For example, operations, such as cutting and deformation that are typically needed in case of sheet metal formed body panels are eliminated in case of the composite body panels 500. Therefore, the assembly line is shortened, leading to a significant reduction in the cost of manufacturing the body panels.

[053] Moreover, considering that the use of composite fibers in the body panels 500 eliminates the need of welding to integrate the body panels 500 to form the body framework of the vehicle. This would also help in avoiding the complexities and disadvantages associated with the welding operation. In addition, owing to the laminate coating of the predefined thickness at each region of the composite body panel 500, significant impact-resistant properties are imparted to the composite body panel 500 of the present disclosure. Therefore, the composite body panel 500 of the present disclosure is strong, durable, cost-effective, lightweight, and operation effective.

[054] While specific language has been used to describe the present subject matter, any limitations arising on account thereto, are not intended. As would be apparent to a person in the art, various working modifications may be made to the method in order to implement the inventive concept as taught herein. The drawings and the foregoing description give examples of implementations. Those skilled in the art will appreciate that one or more of the described elements may well be combined into a single functional element. Alternatively, certain elements may be split into multiple functional elements. Elements from one implementation may be added to another implementation. [055] It is intended that the disclosure and examples be considered as exemplary only, with a true scope and spirit of disclosed embodiments being indicated by the following claims.

Claims

CLAIMS We claim:

1. A composite body panel (500) comprising: a plurality of layers (102) of composite fiber; a plurality of epoxy -based layers (104, wherein the plurality of layers (102) of the composite fiber and the plurality of epoxy-based layers (104) are alternatively positioned in a sandwiching formation to form the body panel (500); and a laminate coating of predefined thickness formed across the surface of each of the plurality of the layers (102) of the composite fiber to facilitate multiaxial loading of the composite body panel (500).

2. The composite body panel (500) as claimed in claim 1, wherein the composite fiber is Fiber Reinforced Polymer (FRP).

3. The composite body panel (500) as claimed in claim 1, wherein the epoxy in each of the plurality of epoxy-based layers (104) is BiSphenol A Epoxy Resin (DGEBA).

4. The composite body panel (500) as claimed in claim 1, comprising a hardener material such that an epoxy-to-hardener ratio in the composite body panel (500) is of2:l.

5. The composite body panel (500) as claimed in claim 1, wherein each of the plurality of layers (102) of the composite fiber comprising one of bidirectional weaves and multi-directional weaves. The composite body panel (500) as claimed in claim 5, wherein the weight of the weaves in the composite fiber is within a range of 350 Grams per Square Meter (GSM) to 450 GSM. The composite body panel (500) as claimed in claim 6, wherein a thickness of a layer (102) of the composite fiber, amongst the plurality of layers (102) of the composite fiber, is more at a spot experiencing greater stresses than the surroundings. A method (400) of forming a composite body panel (500) by a moulding technique, the method (400) comprising: placing a plurality of layers (102) of composite fibers in a patternshaped mould (100); placing a plurality of epoxy -based layers (104) in the mould (100), wherein the plurality of layers (102) of the composite fiber and the plurality of epoxy-based layers (104) are alternatively positioned in a sandwiching formation in the mould (100); adding a hardener material to a slurry formed by melting of the plurality of layers (102) of the composite fibers and the plurality of epoxy -based layers (104) in the mould (100); and extracting the composite body panel (500) from the mould (100), after solidification and cooling of the hardener-infused slurry. The method (400) as claimed in claim 8, comprising placing each of the plurality of layers (102) of the composite fibers such that a direction of the constituent fibers is predefined to achieve maximum strength of the formed composite body panel (500). An electric vehicle comprising: at least one composite body panel (500) comprising: a plurality of layers (102) of composite fiber; a plurality of epoxy -based layers (104), wherein the plurality of layers (102) of the composite fiber and the plurality of epoxy -based layers (104) are alternatively positioned in a sandwiching formation to form the composite body panel (500); and a laminate coating of predefined thickness formed across the surface of each of the plurality of the layers (102) of the composite fiber to facilitate multiaxial loading for the composite body panel (500).