THERMALLY ASSISTED FLANGING AND HEMMING OF ALUMINUM CASTINGS AND EXTRUSIONS AS AN ENABLER TO LOWER COST AND WEIGHT

Abstract

A process and assembly for flanging or hemming an edge of an aluminum casted article, including positioning each of a heating element and a holding pad in proximity to an extending edge of the casted article, heating the edge of the casted article corresponding to the placement of the heating element, and then applying a roller or flattening tool having a contact portion for engaging and bending the heated edge until reformed into a final bent or folded profile. Additional steps include repositioning the at least one heating element or positioning at least one additional heating element at a further location of the casted article, following which a subsequent trimming or final fabricating step is employed to complete the article.

Description

FIELD OF THE INVENTION

The present invention relates generally to forming techniques, assemblies and processes associated with aluminums castings. More specifically, the present invention teaches the selective application of heat to a casted aluminum article prior to bending, this achieving the benefits of reduced weight, cycle time, cost and complexity of the finished article.

BACKGROUND OF THE INVENTION

The integration of aluminum castings into an automotive Body-In-White (BIW) assembly can be dependant on the materials and joining techniques of the surrounding parts. When considering a cast aluminum component, Self Piercing Rivets (SPR's) and Flow Drill Screws (FDS's) are also usually assumed as the default joining process. That assumption comes with accompanied increases to each of piece price, weight, cycle time, system complexity, and in the case of a battery tray, the risk of a leak at each fastener interface for that assembly, and are likely to add the cost to machining each cast surface at that interface, thereby exacerbating the cost increases associated with that construction option.

U.S. Pat. No. 9,896,050 teaches a die-cast battery tray configured as a high-pressure die cast component made from a lightweight metal. The tray element is configured in one piece and has at least one fastening element, by which the battery is fastened to the tray element, with the result that additional fastening elements which are configured separately from the tray element for fastening the battery to the tray element can be avoided or can be kept low.

GB 1,063,427 teaches a two stage manufacture process for semi-finished steel sections formed by casting in a first stage (without heat) and deformed in a second stage with rollers to form desired corner radii.

U.S. Pat. No. 5,799,718 teaches a preheating device for a metal casting channel however doesn't appear to cover post formation (following initial casting or extrusion) heating of portions of the initially formed article to assist with further shaping.

U.S. Pat. No. 8,181,498 discloses a method and technique for shaping a rim of an arched sheet metal although post application of heat doesn't appear to be disclosed.

US 2008/0178968 and US 2008/0178973 both teach an aluminum alloy sheet such as for an automotive outer panel having excellent formability which allows flat hemming, showing no orange peel surfaces and ridging marks after forming and having excellent paint bake hardenability.

SUMMARY OF THE INVENTION

The present invention teaches a system and assembly for thermally assisting the flanging and hemming of a casted aluminum article in order to achieve the benefits of reduced weight, cycle time, cost and complexity of the finished article. Additionally, and by increasing the amount of heat added to the test piece, as well as an adaption of the applied forces when at a desired elevated temperature, it has been found that an aluminum cast sample can be hemmed over a mating piece. In this fashion, thermally assisted flanging and hemming aids in the reduction of weight, cost and complexity of automotive assemblies incorporating a cast aluminum architecture.

BRIEF DESCRIPTION OF THE DRAWINGS

Reference will now be made to the attached drawings, when read in combination with the following detailed description, wherein like reference numerals refer to like parts throughout the several views, and in which:

FIG. 1 is an illustration of an aluminum casting according to an embodiment of the present invention and utilizing thermally assisted flanging and hemming techniques for bending the aluminum casting to aid in the reduction of weight, cost and complexity of the cast aluminum architecture;

FIG. 2 is an enlarged section view taken from FIG. 1 and depicting a flanging or hemming operation for bending a heated edge section of the casting;

FIG. 3 is an illustration similar to FIG. 2 and depicting a final bent shape of the hemmed edge or flange of FIG. 2; and

FIG. 4 is an illustration of a further concept example of a heating and bending operation for forming a flange edge to an aluminum casted article.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

With reference to the attached illustrations, the present invention discloses a system and assembly for thermally assisting the flanging and hemming of a casted aluminum article, such as without limitation a battery tray or the like, in order to achieve the benefits of reduced weight, cycle time, cost and complexity of the finished article. Additionally, and by increasing the amount of heat added to the test piece, as well as an adaption of the applied forces when at a desired elevated temperature, it has been found that an aluminum cast sample can be hemmed over a mating piece. In this fashion, thermally assisted flanging and hemming aids in the reduction of weight, cost and complexity of automotive assemblies incorporating a cast aluminum architecture.

FIG. 1 is an illustration, generally at 10, of an aluminum casting according to an embodiment of the present invention. As previously described, the casting can include without limitation a battery tray and which is bent or re-formed via a thermally assisted flanging and hemming techniques for bending the aluminum casting to aid in the reduction of weight, cost and complexity of the cast aluminum architecture.

In the illustrated embodiment, and as further depicted in FIG. 2, this includes the placement of each of a holding pad 12 and a heating element 14 proximate an edge location 16 of the casting 10 in order to heat/soften the flange edge 16 prior to bending the heated edge section.

The heating elements can be of any known type or construction and can include, without limitation, any of direct heating or indirect methods. In this fashion, the heated and formed or reformed edge can be accomplished according to tighter radii in comparison to that which is possible using cold forming or shaping techniques.

Referencing further FIG. 3, an illustration similar to FIG. 2 is shown and depicting a final bent shape of the hemmed edge or flange of FIG. 2. This includes the placement of a suitable roller or flattening tool, this being represented at 18 and including a contact portion 20 for engaging and bending the heated edge location 16 shown in FIG. 2 until reformed into a final bent or folded profile as depicted at 16′.

Finally, FIG. 4 provides an illustration of a further concept example of a heating and bending operation for forming a flange edge to an aluminum casted article, with a folded location of the flange being shown at 22 and having a reverse folded edge 24, between which is sandwiched a separate plate 26. The purpose of FIG. 4 is to additionally depict the ability to include any type of targeted placement of heating elements in relation to a given location of an aluminum casted article for the purpose of assisting in targeted bending, hemming, or flanging of the casting in order to provide for each of reduced weight, cost and part complexity over prior art techniques.

Having described my invention, other and additional preferred embodiments will become apparent to those skilled in the art to which it pertains, and without deviating from the scope of the appended claims. The detailed description and drawings are further understood to be supportive of the disclosure, the scope of which being defined by the claims. While some of the best modes and other embodiments for carrying out the claimed teachings have been described in detail, various alternative designs and embodiments exist for practicing the disclosure defined in the appended claims.

The foregoing disclosure is further understood as not intended to limit the present disclosure to the precise forms or particular fields of use disclosed. As such, it is contemplated that various alternate embodiments and/or modifications to the present disclosure, whether explicitly described or implied herein, are possible in light of the disclosure. Having thus described embodiments of the present disclosure, a person of ordinary skill in the art will recognize that changes may be made in form and detail without departing from the scope of the present disclosure. Thus, the present disclosure is limited only by the claims.

In the foregoing specification, the disclosure has been described with reference to specific embodiments. However, as one skilled in the art will appreciate, various embodiments disclosed herein can be modified or otherwise implemented in various other ways without departing from the spirit and scope of the disclosure. Accordingly, this description is to be considered as illustrative and is for the purpose of teaching those skilled in the art the manner of making and using various embodiments of the disclosure. It is to be understood that the forms of disclosure herein shown and described are to be taken as representative embodiments. Equivalent elements, materials, processes or steps may be substituted for those representatively illustrated and described herein. Moreover, certain features of the disclosure may be utilized independently of the use of other features, all as would be apparent to one skilled in the art after having the benefit of this description of the disclosure. Expressions such as “including”, “comprising”, “incorporating”, “consisting of”, “have”, “is” used to describe and claim the present disclosure are intended to be construed in a non-exclusive manner, namely allowing for items, components or elements not explicitly described also to be present. Reference to the singular is also to be construed to relate to the plural.

Further, various embodiments disclosed herein are to be taken in the illustrative and explanatory sense, and should in no way be construed as limiting of the present disclosure. All joinder references (e.g., attached, affixed, coupled, connected, and the like) are only used to aid the reader's understanding of the present disclosure, and may not create limitations, particularly as to the position, orientation, or use of the systems and/or methods disclosed herein. Therefore, joinder references, if any, are to be construed broadly. Moreover, such joinder references do not necessarily infer that two elements are directly connected to each other.

Additionally, all numerical terms, such as, but not limited to, “first”, “second”, “third”, “primary”, “secondary”, “main” or any other ordinary and/or numerical terms, should also be taken only as identifiers, to assist the reader's understanding of the various elements, embodiments, variations and/or modifications of the present disclosure, and may not create any limitations, particularly as to the order, or preference, of any element, embodiment, variation and/or modification relative to, or over, another element, embodiment, variation and/or modification.

It will also be appreciated that one or more of the elements depicted in the drawings/figures can also be implemented in a more separated or integrated manner, or even removed or rendered as inoperable in certain cases, as is useful in accordance with a particular application. Additionally, any signal hatches in the drawings/figures should be considered only as exemplary, and not limiting, unless otherwise specifically specified.

Claims

1. A process for flanging or hemming an edge of an aluminum casted article, comprising the steps of: positioning each of a heating element and a holding pad in proximity to an extending edge of the casted article;heating the edge of the casted article corresponding to the placement of the heating element; andapplying any of a roller or flattening tool having a contact portion for engaging and bending the heated edge until reformed into a final bent or folded profile.

2. The process as described in claim 1, further comprising the step of either repositioning the at least one heating element or positioning at least one additional heating element at a further location of the casted article, following which a subsequent trimming or final fabricating step is employed to complete the article.

3. An assembly for flanging or hemming an edge of an aluminum casted article, comprising: at least one heating element placed along an extending location of the blank article in order to heat the extending location;a holding pad placed at a further location of the article in proximity to the heating element; andany of a roller or flattening tool having a contact portion for engaging and bending the heated edge until reformed into a final bent or folded profile.

4. The assembly as described in claim 3, further comprising at least one additional heating element positioned at a further location of the casted article, following which a subsequent trimming or final fabricating step is employed to complete the article