Patent Application
20160297484
The subject invention relates to matable components and, more specifically, to elastically averaged matable components for precise alignment therebetween.
Components, in particular vehicular components used in automotive vehicles, which are to be mated together in a manufacturing process may be mutually located with respect to each other by alignment features that are oversized holes and/or undersized upstanding bosses. Such alignment features are typically sized to provide spacing to freely move the components relative to one another to align them without creating an interference therebetween that would hinder the manufacturing process. One such example includes two-way and/or four-way male alignment features; typically upstanding bosses, which are received into corresponding female alignment features, typically apertures in the form of slots or holes. The components are formed with a predetermined clearance between the male alignment features and their respective female alignment features to match anticipated size and positional variation tolerances of the male and female alignment features that result from manufacturing (or fabrication) variances.
As a result, significant positional variation can occur between two mated components having the aforementioned alignment features, which may contribute to the presence of undesirably large variations in their alignment, particularly with regard to gaps and/or spacing therebetween. In the case where misaligned components are also part of another assembly, such misalignment may also affect the function and/or aesthetic appearance of the entire assembly. Regardless of whether such misalignment is limited to two components or an entire assembly, it can negatively affect function and result in a perception of poor quality. Moreover, clearance between misaligned components may lead to relative motion therebetween, which may cause undesirable noise such as squeaking and rattling, and further result in the perception of poor quality.
In one aspect, an elastically averaged alignment system is provided. The alignment system includes a first component comprising a plurality of alignment pins forming a first group of alignment pins, and a second component comprising an inner wall defining an alignment aperture, the alignment aperture configured to receive the first group of alignment pins to couple the first component and the second component. The alignment pins comprise an elastically deformable material such that when the first group of alignment pins is inserted into the alignment aperture, at least a portion of the alignment pins of the plurality of alignment pins elastically deform to an elastically averaged final configuration to facilitate coupling and aligning the first component and the second component in a desired orientation.
In another aspect, a vehicle is provided. The vehicle includes a body and an elastically averaged alignment system integrally arranged with the body. The elastically averaged alignment system includes a first component comprising a plurality of alignment pins forming a first group of alignment pins, and a second component comprising an inner wall defining an alignment aperture, the alignment aperture configured to receive the first group of alignment pins to couple the first component and the second component. The alignment pins comprise an elastically deformable material such that when the first group of alignment pins is inserted into the alignment aperture, at least a portion of the alignment pins of the plurality of alignment pins elastically deform to an elastically averaged final configuration to facilitate coupling and aligning the first component and the second component in a desired orientation.
In yet another aspect, a method of manufacturing an elastically averaged alignment system is provided. The method includes forming a first component comprising a plurality of alignment pins that form a first group of alignment pins, and forming a second component comprising an inner wall defining an alignment aperture, the alignment aperture configured to receive the first group of alignment pins to couple the first component and the second component. The alignment pins comprise an elastically deformable material such that when the first group of alignment pins is inserted into the alignment aperture, at least a portion of the alignment pins of the plurality of alignment pins elastically deform to an elastically averaged final configuration to facilitate coupling and aligning the first component and the second component in a desired orientation.
The above features and advantages and other features and advantages of the invention are readily apparent from the following detailed description of the invention when taken in connection with the accompanying drawings.
Other features, advantages and details appear, by way of example only, in the following detailed description of embodiments, the detailed description referring to the drawings in which:
The following description is merely exemplary in nature and is not intended to limit the present disclosure, its application or uses. For example, the embodiments shown are applicable to vehicle body panels, but the alignment system disclosed herein may be used with any suitable components to provide elastic averaging for precision location and alignment of all manner of mating components and component applications, including many industrial, consumer product (e.g., consumer electronics, various appliances and the like), transportation, energy and aerospace applications, and particularly including many other types of vehicular components and applications, such as various interior, exterior and under hood vehicular components and applications. It should be understood that throughout the drawings, corresponding reference numerals indicate like or corresponding parts and features.
As used herein, the term “elastically deformable” refers to components, or portions of components, including component features, comprising materials having a generally elastic deformation characteristic, wherein the material is configured to undergo a resiliently reversible change in its shape, size, or both, in response to the application of a force. The force causing the resiliently reversible or elastic deformation of the material may include a tensile, compressive, shear, bending or torsional force, or various combinations of these forces. The elastically deformable materials may exhibit linear elastic deformation, for example that described according to Hooke's law, or non-linear elastic deformation.
Elastic averaging provides elastic deformation of the interface(s) between mated components, wherein the average deformation provides a precise alignment, the manufacturing positional variance being minimized to Xmin, defined by Xmin=X/√N, wherein X is the manufacturing positional variance of the locating features of the mated components and N is the number of features inserted. To obtain elastic averaging, an elastically deformable component is configured to have at least one feature and its contact surface(s) that is over-constrained and provides an interference fit with a mating feature of another component and its contact surface(s). The over-constrained condition and interference fit resiliently reversibly (elastically) deforms at least one of the at least one feature or the mating feature, or both features. The resiliently reversible nature of these features of the components allows repeatable insertion and withdrawal of the components that facilitates their assembly and disassembly. In some embodiments, the elastically deformable component configured to have the at least one feature and associated mating feature disclosed herein may require more than one of such features, depending on the requirements of a particular embodiment. Positional variance of the components may result in varying forces being applied over regions of the contact surfaces that are over-constrained and engaged during insertion of the component in an interference condition. It is to be appreciated that a single inserted component may be elastically averaged with respect to a length of the perimeter of the component. The principles of elastic averaging are described in detail in commonly owned U.S. Pat. No. 8,695,201, the disclosure of which is incorporated by reference herein in its entirety. The embodiments disclosed above provide the ability to convert an existing component that is not compatible with the above-described elastic averaging principles, or that would be further aided with the inclusion of a four-way elastic averaging system as herein disclosed, to an assembly that does facilitate elastic averaging and the benefits associated therewith.
Any suitable elastically deformable material may be used for the mating components and alignment features disclosed herein and discussed further below, particularly those materials that are elastically deformable when formed into the features described herein. This includes various metals, polymers, ceramics, inorganic materials or glasses, or composites of any of the aforementioned materials, or any other combinations thereof suitable for a purpose disclosed herein. Many composite materials are envisioned, including various filled polymers, including glass, ceramic, metal and inorganic material filled polymers, particularly glass, metal, ceramic, inorganic or carbon fiber filled polymers. Any suitable filler morphology may be employed, including all shapes and sizes of particulates or fibers. More particularly any suitable type of fiber may be used, including continuous and discontinuous fibers, woven and unwoven cloths, felts or tows, or a combination thereof. Any suitable metal may be used, including various grades and alloys of steel, cast iron, aluminum, magnesium or titanium, or composites thereof, or any other combinations thereof. Polymers may include both thermoplastic polymers or thermoset polymers, or composites thereof, or any other combinations thereof, including a wide variety of co-polymers and polymer blends. In one embodiment, a preferred plastic material is one having elastic properties so as to deform elastically without fracture, as for example, a material comprising an acrylonitrile butadiene styrene (ABS) polymer, and more particularly a polycarbonate ABS polymer blend (PC/ABS). The material may be in any form and formed or manufactured by any suitable process, including stamped or formed metal, composite or other sheets, forgings, extruded parts, pressed parts, castings, or molded parts and the like, to include the deformable features described herein. The elastically deformable alignment features and associated component may be formed in any suitable manner. For example, the elastically deformable alignment features and the associated component may be integrally formed, or they may be formed entirely separately and subsequently attached together. When integrally formed, they may be formed as a single part from a plastic injection molding machine, for example. When formed separately, they may be formed from different materials to provide a predetermined elastic response characteristic, for example. The material, or materials, may be selected to provide a predetermined elastic response characteristic of any or all of the elastically deformable alignment features, the associated component, or the mating component. The predetermined elastic response characteristic may include, for example, a predetermined elastic modulus.
As used herein, the term vehicle is not limited to just an automobile, truck, van or sport utility vehicle, but includes any self-propelled or towed conveyance suitable for transporting a burden.
In an exemplary embodiment, first component 100 generally includes an outer face 106 and an inner face 108 from which alignment pins 102 extend. Alignment pins 102 are generally solid cylindrical members having a proximal end 110 coupled to inner face 108, and a distal end 112. However, alignment pins 102 may have any cross-sectional shape that enables system 10 to function as described herein. First component 100 may optionally include: one or more stand-offs (not shown) and/or one or more alignment pins 102 having a ledge or shoulder 114 (
Second component 200 generally includes an outer face 206 and an inner face 208. Second component 200 may include a chamfer (not shown) formed in inner face 208 about alignment aperture 204 to facilitate insertion of alignment pins 102 into alignment aperture 204. Further, second component 200 may optionally include one or more stand-offs (not shown) for engaging and supporting first component 100 in spaced relation to second component 200. In an exemplary embodiment, alignment aperture 204 is illustrated as an elongated slot. However, alignment aperture 204 may have any shape that enables system 10 to function as described herein. For example, alignment aperture 204 may be generally circular. In the exemplary embodiment, second component 200 is fabricated from a rigid material such as sheet metal. However, second component 200 may be fabricated from any suitable material that enables system 10 to function as described herein.
While not being limited to any particular structure, first component 100 may be a decorative trim component of a vehicle with the customer-visible side being outer face 106, and second component 200 may be a supporting substructure that is part of, or is attached to, the vehicle and on which first component 100 is fixedly mounted in precise alignment. Alternatively, first component 100 may be an intermediate component located between second component support substructure 200 and a decorative trim component such as a vehicle grille (not shown).
To provide an arrangement where elastically deformable alignment pins 102 are configured and disposed to interferingly, deformably and matingly engage alignment aperture inner wall 202, the outer boundary or perimeter of alignment aperture 204 (i.e., inner wall 202) is smaller than an outer boundary or shape formed by a group 120 of alignment pins 102, which necessarily creates a purposeful interference fit between the elastically deformable alignment pin group 120 and alignment aperture inner wall 202. As such, when inserted into alignment aperture 204, portions of the elastically deformable alignment pins 102 of each group 120 elastically deform to an elastically averaged final configuration that aligns group 120 with the alignment aperture 204 in four planar orthogonal directions (the +/−x-direction and the +/−y-direction). In other arrangements, alignment pins 102 may only be aligned in two planar orthogonal directions (the +/−x-direction or the +/−y-direction). Accordingly, each associated pin group 120 and alignment aperture 204 elastically deform to align at least a portion of first component 100 and second component 200.
Further, a plurality of associated pin groups 120 and alignment apertures 204 may be utilized, for example, as illustrated in
First component 100 may include various formations of alignment pins 102 thereon. For example, as shown in
In view of the foregoing, and with reference now to
An exemplary method of fabricating elastically averaged alignment system 10 includes forming first component 100 with at least one group 120 of alignment pins 102, and forming second component 200 with at least one inner wall 202 defining alignment aperture 204. At least one of the group of alignment pins 102 and the alignment aperture 204 is formed to be elastically deformable such that when alignment pins 102 are inserted into alignment aperture 204, at least one of alignment pins 102 and inner wall 202 elastically deform to an elastically averaged final configuration to facilitate aligning first component 100 and second component 200 in a desired orientation.
Described herein are elastically averaged alignment systems and methods that include a plurality of elastically deformable pins that are elastically averaged within a corresponding alignment aperture. A plurality of corresponding pins and apertures are further elastically averaged to align two or more components in a desired orientation. By using an abundance of small pins, elastic averaging can be achieved without drawing a large amount of material into one feature, which may cause sink marks or depressions. The small pins bend due to an interference condition with the edge of the associated aperture. Each pin will bend to a different degree based on the part variation causing the two mated features to average to a more precise position. The small pins reduce overall gaps and create a consistent gap between the two mated components.
While the invention has been described with reference to exemplary embodiments, it will be understood by those skilled in the art that various changes may be made and equivalents may be substituted for elements thereof without departing from the scope of the invention. In addition, many modifications may be made to adapt a particular situation or material to the teachings of the invention without departing from the essential scope thereof. Therefore, it is intended that the invention not be limited to the particular embodiments disclosed, but that the invention will include all embodiments falling within the scope of the application.
