Patent Publication Number: US-2015078805-A1

Title: Elastically averaged alignment systems and methods

Description:
FIELD OF THE INVENTION 
     The subject invention relates to matable components and, more specifically, to elastically averaged matable components for alignment and retention. 
     BACKGROUND 
     Components, in particular vehicular components 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 variation 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. 
     Additionally, some components, particularly components made of compliant materials, may not remain mated to another component due to vehicle movement, passage of time, or other factors. As such, the male alignment features may become disengaged from corresponding female alignment features leading to additional noise, vibration, or reduced durability. 
     SUMMARY OF THE INVENTION 
     In one aspect, an elastically averaged alignment system is provided. The system includes a first component including an alignment member, the alignment member including a plurality of segments. The system also includes a second component including an inner wall defining an alignment aperture, the alignment aperture configured to receive the alignment member to couple the first component and the second component. The alignment member is an elastically deformable material such that when the alignment member is inserted into the alignment aperture, the alignment member elastically deforms to an elastically averaged final configuration to facilitate 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 including an alignment member, the alignment member including a plurality of segments. The system also includes a second component including an inner wall defining an alignment aperture, the alignment aperture configured to receive the alignment member to couple the first component and the second component. The alignment member is an elastically deformable material such that when the alignment member is inserted into the alignment aperture, the alignment member elastically deforms to an elastically averaged final configuration to facilitate 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. 
    
    
     
       BRIEF DESCRIPTION OF THE 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: 
         FIG. 1  is a perspective view of a disassembled, exemplary elastically averaged alignment system; 
         FIG. 2  is a cross-sectional view of the disassembled elastically averaged alignment system shown in  FIG. 1 ; 
         FIG. 3  is a perspective view of an exemplary alignment member and retention feature that may be used with the system shown in  FIGS. 1 and 2 ; 
         FIG. 4  is perspective view of another exemplary alignment member and retention feature that may be used with the system shown in  FIGS. 1 and 2 ; 
         FIG. 5  is a perspective view of yet another exemplary alignment member and retention feature that may be used with the system shown in  FIGS. 1 and 2 ; 
         FIG. 6  is a perspective view of yet another exemplary alignment member that may be used with the system shown in  FIGS. 1 and 2 ; 
         FIG. 7  is a perspective view of another disassembled, exemplary elastically averaged alignment system; 
         FIG. 8  is a cross-sectional view of the system shown in  FIG. 7  and after assembly; 
         FIG. 9  is a cross-sectional view of the system shown in  FIG. 8  and taken along line  9 - 9 ; and 
         FIG. 10  is a perspective view of the system shown in  FIGS. 8 and 9 . 
     
    
    
     DETAILED DESCRIPTION 
     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&#39;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 X min , defined by X min =S/√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, 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. 
     Described herein are alignment and retention systems, as well as methods for elastically averaged mating assemblies. The alignment and retention systems include retention member(s) that facilitate preventing unintentional disassembly of the elastically averaged mated assemblies, yet allow purposeful disassembly if desired. As such, the alignment and retention systems prevent accidental or premature separation of mated components, thereby maintaining a proper coupling between and desired orientation of two or more components. 
       FIGS. 1 and 2  illustrate an exemplary elastically averaged alignment system  10  that generally includes a first component  100  to be mated to a second component  200 . First component  100  includes an elastically deformable alignment member  102  that includes a first segment  104  and a second segment  106 , and second component  200  includes an inner wall  202  defining an alignment aperture  204 . In the exemplary embodiment, segments  104 ,  106  are substantially semi-circular to define a generally circular alignment member  102 . Alternatively, segments  104 ,  106  may have any suitable shape. Moreover, alignment member  102  may have any suitable number of segments; for example, three segments or four segments (see  FIG. 5 ). Alignment member  102  and alignment aperture  204  are fixedly disposed on or formed integrally with their respective component  100 ,  200  for proper alignment and orientation when components  100  and  200  are mated. Although a single alignment member  102  and alignment aperture  204  are illustrated, components  100  and  200  may have any number and combination of corresponding alignment members  102  and alignment apertures  204 . Elastically deformable alignment member  102  is configured and disposed to interferingly, deformably, and matingly engage alignment aperture  204 , as discussed herein in more detail, to precisely align first component  100  with second component  200  in two or four directions, such as the +/−x-direction and the +/−y-direction of an orthogonal coordinate system, for example, which is herein referred to as two-way and four-way alignment. Moreover, elastically deformable alignment member  102  matingly engages alignment aperture  204  to facilitate a stiff and rigid connection between first component  100  and second component  200 , thereby reducing or preventing relative movement therebetween. 
     In the exemplary embodiment, first component  100  generally includes an outer face  108  and an inner face  110  from which alignment member  102  extends. Alignment member  102  is a generally circular, hollow shape having a central axis  112 , a proximal end  114  coupled to inner face  110 , and a distal end  116 . However, alignment member  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  118  ( FIGS. 1 and 2 ) for engaging and supporting second component  200 . In the exemplary embodiment, first component  100  is fabricated from a rigid material such as plastic. However, first component  100  may be fabricated from any suitable material that enables system  10  to function as described herein. 
     Second component  200  generally includes an outer face  206  and an inner face  208 . In the exemplary embodiment, alignment aperture  204  is illustrated as an elongated slot (e.g., similar to the shape of elastic tube alignment system described in co-pending U.S. patent application Ser. No. 13/187,675 and particularly illustrated in  FIG. 13  of the same). Alternatively, alignment aperture  204  may have any suitable shape that enables system  10  to function as described herein. For example, alignment aperture  204  may have a generally circular cross-section, which may be particularly suited for mating with a multi-segmented alignment member  102  as shown in  FIG. 5 . 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. 
     Moreover, inner wall  202  may be elastically deformable to facilitate added elastic average tuning of system  10 . For example, inner wall  202  and/or a surrounding portion of second component  200  may be made from an elastically deformable material and/or have a smaller thickness or sheet metal gauge than the rest of component  200 . As such, during insertion of alignment member  102  into alignment aperture  204 , inner wall  202  and/or a surrounding portion of component  200  elastically deforms to an elastically averaged final configuration to facilitate aligning first component  100  and second component  200  in a desired orientation. Accordingly, first component tube thickness and second component material and/or gauge may be adjusted to tune the elastic average mating between first component  100  and second component  200 . 
     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  108 , 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. 
     To provide an arrangement where elastically deformable alignment member  102  is configured and disposed to interferingly, deformably and matingly engage inner wall  202  of alignment aperture  204 , the diameter of at least a portion of alignment aperture  204  is less than the diameter of alignment member  102 , which necessarily creates a purposeful interference fit between the elastically deformable alignment member  102  and alignment aperture  204 . Further, second component  200  may include a chamfer  210  to facilitate insertion of alignment member  102 . As such, when inserted into slotted alignment aperture  204 , portions of the elastically deformable alignment member  102  elastically deform to an elastically averaged final configuration that aligns alignment member  102  with the alignment aperture  204  in two planar orthogonal directions (the +/−x-direction or the +/−y-direction. Where alignment aperture  204  is generally circular, alignment member  102  is aligned in four planar orthogonal directions (the +/−x-direction and the +/−y-direction). 
     As shown in  FIGS. 3 and 4 , alignment member  102  may include a retention member  120  that facilitates retention of alignment member  102  within alignment aperture  204 . In the exemplary embodiment of  FIG. 3 , retention member  120  includes a substantially triangular body  122  having an insertion face  124  and a retention face  126 . Angled insertion face  124  facilitates ease of insertion of alignment member  102  into alignment aperture  204 , and after insertion, retention face  126  engages outer face  206  to facilitate preventing alignment member  102  from backing out of alignment aperture  204 . In the exemplary embodiment of  FIG. 4 , retention member  120  includes a barb-shaped body  128  having an insertion face  130  and a retention face  132 . Similarly, angled insertion face  130  facilitates insertion of alignment member  102  and retention face  132  facilitates preventing removal of alignment member  102  from alignment aperture  204 . 
       FIG. 5  illustrates another exemplary embodiment of elastically deformable alignment member  102 , which includes four segments  134 ,  136 ,  138 , and  140 . Segments  134  and  136  are opposed and segments  138  and  140  are opposed to define a substantially circular-shaped alignment member  102 . Each segment  134 ,  136 ,  138 , and  140  may have a retention member  120  that includes a first angled portion  142  and a second angled portion  144  each extending angularly from alignment member distal end  116 . First angled portion  142  defines an insertion face  146  configured to engage inner wall  202  and/or chamfer  210  during insertion of alignment member  102  within alignment aperture  204 . In the exemplary embodiment, insertion face  146  extends from an alignment member outer wall  103  at an angle “a”, which may be variably designed such that a predetermined force will be required to insert alignment member  102 . For example, as angle “a” is increased, the force required for alignment member insertion is reduced, and vice versa. Similarly, second angled portion  144  defines a retention face  148  configured to engage outer surface  206  and/or inner wall  202  following insertion and during removal of alignment member  102  from within alignment aperture  204 . In the exemplary embodiment, retention face  148  extends from alignment member outer wall  103  at an angle “β”, which is variably designed such that a predetermined force will be required to remove alignment member  102  from alignment aperture  204 . For example, as angle “β” is increased, the force requirement for alignment member removal is reduced, and vice versa. In the exemplary embodiment, angle “β” is less than angle “a” such that the force required for alignment member removal is greater than the force required for alignment member insertion. This facilitates ease of assembly, but removal requires a purposeful force (i.e., forces larger than experienced during typical vehicle use). 
     As shown in  FIGS. 3-5 , each segment  104 ,  106 ,  134 ,  136 ,  138  and  140  includes a single retention member  120 . However, each segment may include any number of retention members  120  that enables system  10  to function as described herein. Moreover, retention members  120  may be positioned in any desired location along outer wall  103  between proximal end  114  and distal end  116 , or may comprise the entire length of outer wall  103  therebetween. 
       FIG. 6  illustrates another exemplary embodiment of elastically deformable alignment member  102  that includes a pair of removal tabs  150 . Each removal tab  150  extends from distal end  116  of first segment  104  and second segment  106 . Removal tabs  150  facilitate removal of alignment member  102  from alignment aperture  204  such that tabs  150  may be biased toward one another, thereby biasing elastically deformable segments  104  and  106  toward each other. Accordingly, segments  104  and  106  are biased away from and at least partially out of contact with inner wall  202  such that alignment member  102  may then be removed from within alignment aperture  204 . Although not shown, the alignment member of  FIG. 6  may also include a retention feature  120  as shown in  FIGS. 3-5 . 
     While  FIGS. 1 and 2  depict a single elastically deformable alignment member  102  in a corresponding slotted aperture  204  to provide two-way alignment of the first component  100  relative to the second component  200 , it will be appreciated that the scope of the invention is not so limited and encompasses other quantities and types of elastically deformable alignment elements used in conjunction with the elastically deformable alignment member  102  and corresponding circular aperture  204 . 
     With further reference to  FIGS. 1 and 2 , standoffs  118  may be spaced relative to the outer diameter of alignment aperture  204  such that they provide a support platform at a height “h” above first component inner face  110 . Second component inner face  208  rests upon standoffs  118  when elastically deformable alignment member  102  is inserted into alignment aperture  204 . Stated alternatively, standoffs  118  are disposed and configured to provide a final positional orientation between alignment aperture  204  and elastically deformable alignment element  102  at an elevation “h” above the base, inner face  110 , of elastically deformable alignment member  102 . While  FIG. 1  depicts three standoffs  118  in the form of posts at a height “h” relative to first component inner face  110 , it will be appreciated that the scope of the invention is not so limited and also encompasses other numbers and shapes of standoffs  118  suitable for a purpose disclosed herein, and also encompasses a standoff in the form of a continuous ring disposed around alignment member  102 . All such alternative standoff arrangements are contemplated and considered within the scope of the invention disclosed herein. Moreover, while  FIGS. 1 and 2  depict standoffs  118  integrally formed on inner face  110 , it will be appreciated that a similar function may be achieved by integrally forming standoffs  118  on second component inner face  208 , which is herein contemplated and considered to be within the scope of the invention disclosed herein. Alternatively, system  10  may not include standoffs. 
     In view of the foregoing, and with reference now to  FIGS. 7-10 , it will be appreciated that an exemplary embodiment of the invention includes elastically averaging alignment system  10  implemented in a vehicle (not shown). For example, second component  200  may be a vehicle body door handle  40  configured to receive first component  100 , which may be a door handle insert  42 . However, it is contemplated that an elastically averaging alignment system  10  as herein disclosed may be utilized with other features of the vehicle, such as exterior body trim, interior trim, inserts, bezels, or decorative trim. 
     As shown in  FIGS. 7-9 , insert  42  includes a plurality of alignment members  102   a ,  102   b ,  102   c , and door handle  40  includes a plurality of corresponding alignment apertures  204   a ,  204   b ,  204   c . Elastically deformable alignment members  102   a ,  102   b ,  102   c  facilitate elastic averaging over the total of alignment members  102  to facilitate substantially aligning centerlines  112   a ,  112   b ,  112   c  with centerlines  205   a ,  205   b , and  205   c  of corresponding alignment apertures  204   a ,  204   b ,  204   c , and leading to an improved coupling between first component  100  and second component  200 . Although not shown, each of alignment members  102   a ,  102   b ,  102   c  may include one or more retention features  120  as described herein. 
     In the exemplary embodiment, insert  42  also includes an elastically deformable alignment wedge  152  having two end segments  154  and a middle segment  156 . Door handle  40  includes a corresponding alignment wedge aperture  212  defined by an inner wall  214 . Elastically deformable alignment wedge  152  is configured and disposed to interferingly, deformably, and matingly engage inner wall  214  of alignment wedge aperture  212 , to precisely align insert  42  with door handle  40  in two or four directions, such as the +/−z-direction and the +/−y-direction of an orthogonal coordinate system. As such, when inserted into alignment wedge aperture  212 , end segments  154  deform towards middle segment  156  to align insert  42  and door handle  40 . Moreover, elastically deformable alignment wedge  152  matingly engages alignment wedge aperture  212  to facilitate a stiff and rigid connection between door handle  40  and insert  42 , thereby reducing or preventing relative movement therebetween. Although a single alignment wedge  152  is illustrated, system  10  may have any suitable number of alignment wedges  152  and corresponding alignment wedge apertures  212 . 
     Door handle  40  may also include a biasing member  216  coupled to inner face  208  and that seats against inner face  110  when door handle insert  42  is coupled to door handle  40 . Biasing member  216  is biased into contact with inner face  110  to facilitate preventing rattling between door handle  40  and insert  42  when the vehicle is in motion. For example, biasing member  216  may be a spring or the like. Although biasing member  216  is illustrated as coupled to second component  200 , a biasing member may also be coupled to first component  100 . 
     As shown in  FIG. 8 , alignment member  102   a  is positioned on the end of first component  100  to precisely align and orient an end  109  of first component  100  with an end  207  of second component  200 . As such, alignment member  102   a  elastically deforms within alignment aperture  204   a  such that first and second segments  104  and  106 ,  FIGS. 1-6 , are deflected toward each other to align centerline  112   a  substantially with centerline  205   a  of aperture  204   a  for alignment substantially in the +/−x direction. It should also be understood that alignment member  102   a  will have clearance to alignment aperture  204   a  in the +/−y direction. Due, for example, to the inherent manufacturing tolerance and variance of oversized alignment apertures  204   a - c , such apertures  204   a - c  may be formed in a location other than the exact design location. Alignment members  102   b  and  102   c  elastically deform within respective alignment apertures  204   b  and  204   c  substantially in the +/−y direction. As shown in this embodiment, as an example, the left and right portions of alignment members  102   b ,  102   c  do not contact the left or right end of slot apertures  204   b ,  204   c  due to the length of slotted apertures in the +/−x direction. 
     As shown in  FIG. 9 , alignment member  102   b  elastically deforms within respective alignment aperture  204   b  to facilitate bringing centerline  112   b  more in-line with centerline  205   b  of alignment aperture  204   b . As an example, due to manufacturing variances, the right portion of member  102   b  deforms more than the left portion of alignment member  102   b  to elastically average the member positioning and substantially align the centerlines such that centerline  112   b  is only slightly off-set from centerline  205   b  of respective alignment aperture  204   b . Although not shown, alignment member  102   c  behaves in a manner similar to alignment member  102   b . However, it should be understood that any combination of deformation to alignment members  102  may occur due to the variance between mating parts  100 ,  200 . 
     Accordingly, alignment members  102   a ,  102   b , and  102   c  elastically average the alignment features of first and second components  100 ,  200  to couple them in a desired orientation. Additionally, alignment wedge  152  elastically deforms within alignment wedge aperture  212  such that end segments  154  are deflected toward middle segment  156  and a wedge centerline  112   d . Accordingly, alignment wedge  152  elastically deforms to facilitate aligning centerline  112   d  substantially with a centerline  205   d  of aperture  212  to align and couple first and second components  100  and  200  in a desired orientation. 
     Elastically averaged mating assembly systems are described herein. The systems generally include a first component with an elastically deformable alignment member positioned for insertion into an alignment aperture of a second component. The mating of the first and second components is elastically averaged over a corresponding pair or pairs of elastically deformable alignment members and alignment apertures to precisely mate the components in a desired orientation. The systems may include a retention member for self-retention of the alignment member within the alignment aperture, and a biasing member for preventing rattling between the first and second components. Further, the retention features facilitate preventing unintentional disassembly of elastically averaged mated components, tunable elastically averaged mating systems, and reducing or eliminating the need for fasteners to mate the 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.