Patent Application
20140301103
The present invention relates to an elastically deformable flange locator arrangement for aligning components relative to each other, as well as a method of reducing positional variation for components of the elastically deformable flange locator arrangement.
Currently, components which are to be mated together in a manufacturing process are subject to positional variation based on the mating arrangements used to assemble the components. One common arrangement includes components mutually located with respect to each other by 2-way and/or 4-way male alignment features, typically upstanding bosses, which are received into corresponding female alignment features, typically apertures in the form of openings and/or slots. Alternatively, adhesives or welding processes may be employed to mate parts. Regardless of the precise mating arrangement, a clearance typically exists between at least a portion of the mated components, which is predetermined to match anticipated size and positional variation tolerances of the mating features as a result of manufacturing (or fabrication) variances. As a result, the occurrence of significant positional variation between the mated components, which contributes to the presence of undesirably large and varying gaps and otherwise poor fit may occur.
In one exemplary embodiment, an elastically deformable flange locator arrangement includes a first component having a first engagement surface. Also included is a second component configured to be mated with the first component. Further included is a first portion of the second component. Yet further included is a second portion of the second component extending relatively perpendicularly from the first portion proximate a perimeter of the first portion, the second portion having a second engagement surface, wherein the second portion is configured to elastically deform at a first interface upon contact between the first engagement surface and the second engagement surface.
In another exemplary embodiment, an automotive lighting assembly includes an automotive lighting housing. Also included is a channel formed and extending proximate a housing perimeter of the automotive lighting housing, the channel comprising a first channel engagement surface and a second channel engagement surface. Further included is a lens configured to be mated with the automotive lighting housing. Yet further included is a first portion of the lens. Also included is a second portion and a third portion of the lens, each extending relatively perpendicularly from the first portion proximate a lens perimeter, the second portion having a first lens engagement surface and the third portion having a second lens engagement surface, wherein at least one of the first lens engagement surface and the second lens engagement surface is configured to elastically deform upon contact with the channel of the automotive lighting housing.
In yet another exemplary embodiment, a method of reducing positional variation of mated components is provided. The method includes forming a first engagement surface in a first component. The method also includes contacting a second engagement surface located proximate a perimeter of a second component with the first engagement surface, wherein the second component comprises a first portion and a second portion, the second portion extending relatively perpendicularly from the first portion, wherein the second portion comprises the second engagement surface. The method further includes elastically deforming second portion of the second component upon contacting the second engagement surface with the first engagement surface. The method yet further includes performing an elastic averaging of the elastic deformation over the second engagement surface, wherein upon reaching a fully engaged position of the second portion of the second component a fitted alignment between the first component and the second component is established.
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:
Referring to
Although illustrated in a specific geometry, the first component 12 and the second component 14 may be configured in countless geometries. Regardless of the precise geometry of the first component 12 and the second component 14, the second component 14 is configured to align with and fittingly mate with the first component 12, which will be described in detail below. In an alternative embodiment, rather than two components comprising the elastically deformable flange locator arrangement 10, additional layers or components may be included. It is to be appreciated that the elastically deformable flange locator arrangement 10 is to be employed for providing a self-aligning relationship between components, such as the first component 12 and the second component 14, while also assisting in securely mating the components to each other.
Referring now to
The second component 14 includes a first portion 22 and a second portion 24. The first portion 22 comprises a main portion of the second component 14 that is to be mated with the first component 12. The first portion 22 may be substantially planar or curvilinear and is aligned relatively parallel to the base wall 18 and the elevated wall 20 of the first component 12. The second portion 24 extends relatively non-perpendicularly from the first portion 22 toward the first component 12 and includes a second engagement surface 26. The second portion 24 is typically disposed proximate a perimeter of the first portion 22 of the second component 14, but may be disposed inwardly from the perimeter. Ultimately, the location of the second portion 24 is determined by the location of the first engagement surface 16 of the first component 12. Specifically, the first engagement surface 16 and the second engagement surface 26 are aligned to contact each other upon mating of the first component 12 and the second component 14.
Similar to the first engagement surface 16, the second engagement surface 26 extends in a peripheral manner around the first portion 22 of the second component 14, as well as continuously around a portion of the second component 14. The second engagement surface 26 comprises a second engagement surface length, also referred to herein as a second perimeter. The second perimeter is less than the first perimeter described above, such that the second engagement surface 26 is disposed radially inwardly of the first engagement surface 16. More particularly, the second engagement surface 26 is positioned to ensure contact between the surfaces, with such a contact region comprising a first interface region 28. The second portion 24 is positioned and engaged with the first engagement surface 16 of the first component 12 upon translation of the second component 14 toward the base wall 18. The second engagement surface 26 engages the first engagement surface 16 at a position spaced from the base wall 18. Subsequent translation of the second portion 24 toward the base wall 18 results in an elastic deformation of the second portion 24 at the first interface region 28. Furthermore, as shown, the first engagement surface 16 includes a chamfer portion 21 disposed at a distal end from the base wall 18. The chamfer portion 21 comprises a beveled surface and is configured to provide a “lead-in” region for the second engagement surface 26. Numerous angles of the chamfer portion 21 are contemplated. In addition to the “lead-in” benefit provided by the chamfer portion 21, the angled surface enhances a contact interference condition between the first component 12 and the second component 14 by increasing the compressive surface area that is available to impart a compressive force on the second engagement surface 26.
Any suitable elastically deformable material may be used for the second component 24. More specifically, elastically deformable material is disposed proximate, or integral to, the second engagement surface 26 of the second component 24. 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 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.
Numerous examples of materials that may at least partially form the components include various metals, polymers, ceramics, inorganic materials or glasses, or composites of any of the aforementioned materials, or any other combinations thereof 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), such as an ABS acrylic. 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 material, or materials, may be selected to provide a predetermined elastic response characteristic of the second portion 24. The predetermined elastic response characteristic may include, for example, a predetermined elastic modulus.
The precise position where engagement between the first engagement surface 16 and the second engagement surface 26 occurs will vary depending on positional variance imposed by manufacturing factors. Due to the elastically deformable properties of the elastic material comprising the second portion 24, the criticality of the initial location of engagement is reduced. Further insertion of the second portion 24 along the first engagement surface 16 toward the base wall 18 ultimately leads to a fully engaged position of the second portion 24, and more particularly the second component 14. It is contemplated that the second portion 24 may engage the base wall 18 of the first component 12 or may not contact the base wall 18. The dimensions of the second portion 24 and the first engagement surface 16, as well as the elastic properties of the elastic material(s), ultimately dictate the fully engaged position. In the fully engaged position, the second portion 24 is in contact with the first engagement surface 16 along an entirety of the second engagement surface 26.
Irrespective of the precise location of the fully engaged position, fitted engagement between the first engagement surface 16 and the second engagement surface 26 is achieved by elastically averaging the deformation along the first interface region 28, thereby positioning the second component 14 to the first component 12. Regardless of whether the first component 12 and the second component 14 are retained merely by engagement between the first engagement surface 16 and the second engagement surface 26 or in conjunction with additional retaining features, the elastic deformation of the second portion 24 elastically averages any positional errors of the first component 12 and the second component 14. In other words, gaps that would otherwise be present due to positional errors associated with portions or segments of the first component 12 and the second component 14, particularly locating and retaining features, are eliminated by offsetting the gaps with an over-constrained condition along other portions or segments of the first engagement surface 16 and the second engagement surface 26. Such errors are accounted for by averaging deformation of the second portion 24 over the second engagement surface 26.
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. 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, co-pending U.S. patent application Ser. No. 13/187,675, 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 to an assembly that does facilitate elastic averaging and the benefits associated therewith.
Referring to
Referring now to
Rather than the semi-trough like “fall off” portion of the first component 12 of the first embodiments, the third embodiment includes a channel 40. The channel 40 includes the first engagement surface 16, also referred to as a first channel engagement surface, the base wall 18 and a second channel engagement surface 42. In addition to engagement between the first engagement surface 16 and the second engagement surface 26, the second portion 24 of the second component 14 includes an additional engagement surface 44 configured to contact the second channel engagement surface 42. The distance between the second engagement surface 26 and the additional engagement surface 44 may be referred to as a second portion width. The second portion width is greater than the width of the channel 40, such that contact between the second portion 24 and the channel 40 is ensured proximate at least one of the interfaces. As with the first engagement surface 16, the second channel engagement surface 42 includes an additional chamfer portion 45 for engaging with and compressing the additional engagement surface 44. The structure and function of the chamfer portions is described in detail above.
Referring now to
In addition to the first portion 22 and the second portion 24 of the second component 14, a third portion 50 is included in the third embodiment. The third portion 50 is constructed and oriented similarly to that of the second portion 24 and includes a third portion engagement surface 52. Similar to the second embodiment, the first component 12 includes the channel 40 having the first channel engagement surface 16, the base wall 18 and the second channel engagement surface 42. Extending longitudinally through the second component 14 is a recess 54 disposed between the second portion 24 and the third portion 50. The recess 54 extends from an end 56 toward the first portion 22 of the second component 14.
The second portion 24 and the third portion 50 of the second component 14 are positioned and engaged with the channel 40 of the first component 12 upon translation of the second component 14 toward the base wall 18. The second engagement surface 26 and the third portion engagement surface 52 engage the first channel engagement surface 16 and the second channel engagement surface 42, respectively, at a position spaced from the base wall 18 within the channel 40. Subsequent translation of the second portion 24 and the third portion 50 toward the base wall 18 results in an elastic deformation at an interface between the first channel engagement surface 16 and the second engagement surface 26, as well as at an interface between the third portion engagement surface 52 and the second channel engagement surface 42. Depending on the positional variance of the features of the first component 12 and the second component 14, elastic deformation of one or both of the second portion 24 and the third portion 50 may occur in response to resistance imposed on the second engagement surface 26 and the third portion engagement surface 52 by the channel 40. It is to be appreciated that elastic deformation of the second portion 24 and the third portion 50 is further facilitated by the presence of the recess 54 disposed between the second portion 24 and the third portion 50. The void of material proximate the recess 54 enhances the flexibility of the second portion 24 and the third portion 50 in regions closely located to the recess 54. Elastic averaging of the elastic deformation of the second component 14 is averaged in aggregate between the second portion 24 and the third portion 50, similar to the elastic averaging described in detail above.
Referring to
As with previous embodiments, the first component 12 also includes the chamfer portion 21 for lead-in purposes, but the second engagement surface 26 of the second portion 24 primarily engages the first channel engagement surface 16 along a portion of the first channel engagement surface 16 that is similarly aligned in a substantially orthogonal manner to the base wall 18. Similarly, the third portion engagement surface 52 of the third portion 50 primarily engages the second channel engagement surface 42 along a portion of the second channel engagement surface 42 that is similarly aligned in a substantially orthogonal manner to the base wall 18.
In one embodiment (
A method of reducing positional variation of mated components 100 is also provided, as illustrated in
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.
