Abstract:
A mounting system for a fire detection system for a turbofan engine propulsion system is provided to mount fire detection sensors on the inner fixed structure (IFS) of the nacelle. The mounting system mounts to an inner, engine facing surface of the IFS. Two IFS halves cooperate to form a substantially enclosed space around an engine core. The mounting system includes part of a fastening system mounted to the IFS, and an orientation clip mounted to a thermal blanket. Brackets for mounting the fire detection system sensing wires are positioned on the orientation clip, and the fastening system fixes the bracket to the IFS and traps the thermal blanket therebetween.

Description:
[0001]    This application claims priority to U.S. patent application Ser. No. 61/642,408 filed May 3, 2012. 
     
    
     BACKGROUND 
       [0002]    A typical aircraft turbofan propulsion system includes a jet engine (also called an engine core, or simply a core), a nacelle that surrounds the engine core, and a fan driven by the engine that draws in a flow of air that is split into a bypass airflow and an engine core airflow. The nacelle defines a bypass duct that surrounds the engine core. The bypass airflow is transported through the bypass duct and exits the bypass duct at a high speed at an aft end thereof. The engine core includes a multi-stage compressor to compress the engine core airflow, a combustor to add thermal energy to the compressed engine core airflow, and a turbine section downstream of the combustor to produce mechanical power from the engine core airflow. The mechanical power from the turbine section drives the compressor and the fan. After exiting the turbine section, the engine core airflow exits through an exhaust nozzle at the aft end of the engine. 
         [0003]    Surrounding the engine core is a fire zone in which elevated temperatures must be quickly and reliably detected so that, in appropriate conditions, fire suppression can be employed, or other action taken to ensure the safety of the aircraft. 
         [0004]    A fire detection system typically includes one or more thermal detectors, or other types of sensing elements, to provide a warning during engine operation if excess temperatures are detected or other conditions indicative of a fire are detected. The sensing elements are attached to a mounting system, which is attached either to the nacelle, to the engine core itself, and/or to an engine support structure. The sensing elements are suspended away from the surface of the nacelle, the engine core, or the support structure by a mounting system such that the sensing elements detect the conditions in an air space between the engine core and the nacelle. 
         [0005]    The spacing of the sensing elements away from the engine core or support structure competes for space also used by other components. In addition to the fire detection system, the space between the engine core and the nacelle is filled with a multitude of components such as valves, tubes, ducts, wires, generators, gearboxes, sensors, etc. In many installations, the space between the engine core and the nacelle is further limited by the need to provide a thermal blanket surrounding all or part of the engine core. The thermal blanket provides thermal and acoustic insulation during engine operation. In many installations, such as nacelles constructed with composite panels, the thermal blanket might be necessary for shielding the composite panel from engine operating temperatures that could damage the composite panel. 
         [0006]    A compact and light weight mounting system is desired for mounting the fire detection system in accordance with aircraft regulations and operating requirements, while also ensuring simplicity and accuracy of the installation/assembly and allowing flexibility in the placement of the mounting system components. 
       SUMMARY 
       [0007]    According to an aspect of the invention, an assembly is provided for a propulsion system that include a jet engine housed within a nacelle. The assembly includes a thermal blanket and a bracket orientation clip. The blanket is configured to at least partially surround the engine. The blanket is also configured to thermally shield at least a portion of the nacelle from heat energy radiated by the engine. The clip includes a base and a plurality of anti-rotation tabs. The base is bonded to the blanket, and the tabs extend out from the base and away from the blanket. 
         [0008]    According to another aspect of the invention, an assembly is provided for a turbofan propulsion system that includes a jet engine and a nacelle. The assembly includes a blanket and a fire detection system. The blanket is configured to thermally insulate at least a portion of the nacelle from the engine. The fire detection system includes a sensing wire, a bracket and an orientation clip that is bonded to the blanket. The bracket is configured to locate the sensing wire a distance from the blanket. The clip is arranged between the blanket and the bracket. The clip is configured to limit or substantially prevent rotation of the bracket relative to the blanket. 
         [0009]    According to still another aspect of the invention, another assembly is provided for a turbofan propulsion system that includes a jet engine. The assembly includes a nacelle, a blanket, a clip, a bracket and a fastening mechanism The blanket is configured to arrange between at least a portion of the nacelle and the engine. The clip is bonded to the blanket, and includes a base and a plurality of tabs that are connected to the base. The bracket is nested with the clip laterally between at least some of the tabs. The fastening mechanism connects the bracket to the nacelle. 
         [0010]    The clip may be configured to limit or substantially present rotation of the bracket relative to the blanket and/or the nacelle. 
         [0011]    The assembly may include an inner fixed structure for the nacelle, and a fastening mechanism. The fastening mechanism may connect the bracket to the inner fixed structure. 
         [0012]    The assembly may include a locating feature configured with the inner fixed structure. The fastening mechanism may be connected to the locating feature. 
         [0013]    The assembly may include a mounting block connected to the bracket and supporting the sensing wire. 
         [0014]    The base may be welded to the blanket. The base may also or alternatively be adhered or otherwise bonded to the blanket. 
         [0015]    The base may be configured as or otherwise include a generally rectangular and/or flat portion of the clip. 
         [0016]    The tabs may be respectively arranged at corners of the base. 
         [0017]    The base may extend laterally between a pair of the tabs. 
         [0018]    The assembly may include a bracket for a fire detection system. The clip may be arranged between the blanket and the bracket. The clip may be configured to limit or substantially prevent rotation of the bracket relative to the blanket. 
         [0019]    The bracket may be nested with the clip laterally between a pair of the tabs. 
         [0020]    The assembly may include a fastening mechanism for connecting the bracket to the nacelle. The fastening mechanism may project through the bracket, the clip and the thermal blanket. The fastening mechanism may be configured as or otherwise include a rivet, or a head connected to a threaded sleeve, or any other type of fastener. 
         [0021]    The assembly may include a mounting block connected to the bracket. The mounting block may be configured to support a sensing wire for the fire detection system. 
         [0022]    The assembly may also include a second mounting block connected to the bracket. The second mounting block may be configured to support a second sensing wire for the fire detection system. 
         [0023]    The assembly may include a second mounting block connected to a second mounting bracket for the fire detection system. The second mounting block may be configured to support a second sensing wire for the fire detection system. The clip may be arranged between the blanket and the second bracket. The clip may be configured to limit or substantially prevent rotation of the second bracket relative to the blanket. 
         [0024]    Other features and advantages of the present invention should be apparent from the following description of the preferred embodiments, which illustrate, by way of example, the principles of the invention. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0025]      FIG. 1  is a side schematic view of a turbofan propulsion system that includes a fire detection system with sensing element supports in accordance with the embodiments disclosed herein. 
           [0026]      FIG. 2  is a perspective view of the propulsion system in  FIG. 1  from an aft end looking forward. 
           [0027]      FIG. 3  is a side view of an inside surface of a left-side inner fixed structure illustrated in  FIG. 2  configured with the fire detection system in accordance with the embodiments disclosed herein. 
           [0028]      FIG. 4  is a perspective view of an exemplary fire detection system. 
           [0029]      FIG. 5  is a perspective view of certain mounting system details for the fire detection system illustrated in  FIG. 4 . 
           [0030]      FIG. 6  is a perspective view of additional mounting system details in accordance with one of the embodiments disclosed herein. 
           [0031]      FIG. 7  is a perspective view of an anti-rotation clip in accordance with embodiments disclosed herein. 
           [0032]      FIG. 8  is a perspective view of a support assembly with dual brackets in accordance with embodiments disclosed herein. 
           [0033]      FIG. 9  is a cross-sectional side view of the support assembly illustrated in  FIG. 8  installed on an inner fixed structure and holding a thermal blanket in place. 
           [0034]      FIG. 10  is a perspective view of a support assembly in accordance with a second one of the embodiments disclosed herein. 
           [0035]      FIG. 11  is a plan view of the support assembly illustrated in  FIG. 10 . 
           [0036]      FIG. 12  is a cross-sectional side view of the support assembly illustrated in  FIG. 10  installed on an inner fixed structure and holding a thermal blanket in place. 
           [0037]      FIG. 13  is a plan view of a support assembly in accordance with embodiments disclosed herein and other connections. 
           [0038]      FIG. 14  is a cross-sectional side view of the support assembly illustrated in  FIG. 13 , showing the mounting of the support assembly to the inner fixed structure with through-fasteners. 
           [0039]      FIG. 15  is a simplified cross-sectional side view of a support assembly embodiment that fastens a thermal blanket and is attached to an inner fixed structure with a stud and nut combination. 
           [0040]      FIG. 16  is a simplified cross-sectional side view of a support assembly embodiment for use without a thermal blanket and attached to an inner fixed structure with a stud and nut combination. 
           [0041]      FIG. 17  is a simplified cross-sectional side view of a support assembly embodiment for use without a thermal blanket and attached to an inner fixed structure with a rivet configuration. 
       
    
    
     DETAILED DESCRIPTION 
       [0042]    In the following description, various embodiments will be described. For purposes of explanation, specific configurations and details are set forth in order to provide a thorough understanding of the embodiments. It will also be apparent to one skilled in the art that the present invention can be practiced without the specific details described herein. Furthermore, well-known features may be omitted or simplified in order not to obscure the embodiment being described. 
         [0043]      FIG. 1  is a side schematic view of a jet engine  114  (e.g., an engine core) enclosed within a nacelle  100  to form a turbofan propulsion system. The engine  114  is supported from a wing  110  of an aircraft by pylon structure  112 . An inlet cowl  116  of the nacelle  100  is located at a forward end of the nacelle  100 . A fan cowl  118  surrounds a turbine fan which compresses and accelerates the incoming air stream. A thrust reverser  120  is configured at an aft end of the nacelle  100  to help slow the aircraft upon landing. A thrust reverser panel or sleeve  122  slides along a path defined by one or more beams on the thrust reverser  120 . When the thrust reverser panel  122  is deployed upon landing, it causes thrust from the engine  114  to be diverted and partially reversed so that aircraft speed is reduced. 
         [0044]      FIG. 2  is a perspective view of the engine  114  and the nacelle  100  from the aft end looking forward. For simplification and a better view, several components are not shown such as the fan, the fan cowl, the inlet cowl, and the right half of the thrust reverser  120 . The left half  202  of the thrust reverser  120  is shown in a raised position. The left half  202  includes an inner surface which faces the engine  114  formed in the inner fixed structure (IFS)  206  of the left half  202 . The thrust reverser  120  left half and right half are closed during flight, forming a substantially enclosed shell around the engine  114  with the left half IFS and the right half IFS. Sensors of fire detection systems  208 ,  210  are mounted on the inner surface of the IFS  206  of the nacelle. 
         [0045]      FIG. 3  is a side view of the inner surface of the IFS  206  shown in  FIG. 2 , showing the fire detection system mounted thereon in accordance with the embodiments disclosed herein. The aft end is to the left of the drawing, the forward end is to the right of the drawing. 
         [0046]      FIG. 4  is a perspective view of a fire detection system  400 .  FIG. 4  shows that the fire detection system  400  may include spaced-apart mounting blocks  402  through which sensing wires  404  are passed. As described further below, the sensing wires  404  are located at a position that is a predetermined distance from the nacelle by support assemblies  406 ,  408 ,  410 ,  412 . The support assembly  406  may be configured as a double-bracket arrangement that supports two pairs of the sensing wires  404  and corresponding mounting blocks  402 . The support assembly  408  may be configured as a single-bracket arrangement that supports a single pair of the sensing wires  404  and corresponding mounting blocks  402 . The support assemblies  410  and  412  may each be configured as a bracket that supports additional wires and connections for the fire detection system, as well as a single wire and connection. 
         [0047]      FIG. 5  is a perspective view of a sensor assembly  500  that includes a pair of mounting blocks  402  and a double-bracket arrangement  406  such as those illustrated in  FIG. 4 .  FIG. 5  shows that the mounting block  402  may be generally cylindrical in shape, with the sensing wire  404  passing out from each end of the cylinder. A mounting bracket  510  holds the mounting blocks  402  in fixed position and facilitates mounting the sensor assembly  500  to a support assembly, described in more detail below. The sensor assembly  500  may be mounted to the support assembly using, for example, a fastener  512  such as a screw or the like. 
         [0048]      FIG. 6  is a perspective view of a single-bracket support assembly  600  in accordance with the embodiments disclosed herein. The support assembly  600  includes a bracket orientation clip  602  on which is placed a bracket  604 . The bracket  604  has a planar surface  606  with a bore  607  formed therein and sized to receive a fastening mechanism (described in more detail below). When the fire detection system is attached to the IFS, the retainer urges the bracket against the aircraft IFS (see, e.g.,  FIG. 9 ). The bracket  604  includes an attachment surface  608  configured to receive a sensor assembly  500  and its associated mounting bracket  510 . The attachment surface  608  is offset from the planar surface  606  so that the attachment surface  608  is a predetermined distance away from the IFS when the bracket assembly  600  is installed. For example, in  FIG. 6 , a connecting portion  614  joins the attachment surface  608  to the planar surface  606  such that the attachment surface  608  is substantially parallel to the planar surface  606  and spaced away at a predetermined distance. 
         [0049]    The spacing distance of the attachment surface  608  from the IFS is selected so that when the support assembly  600  is coupled to the IFS at the planar surface  606 , the attachment surface  608  is spaced away from the IFS by a predetermined distance. The connecting portion  614  shown in  FIG. 6  joins the planar surface  606  to the attachment surface  608  at an angle, generally forming a Z-shape when viewed in cross-section. The connecting portion  614 , however, may be provided in different shapes. For example, a curved shape may be used in place of the flat portion between the planar surface  606  and attachment surface  608 , or more convoluted shapes may be used, as desired for an application and operating regimen. 
         [0050]    Referring to  FIG. 7 , the orientation clip  602  includes a substantially planar, four-sided flat portion  702  (e.g., a generally rectangular base) with raised tabs  704 ,  706 ,  708 ,  710  (e.g., anti-rotation tabs) at approximately each corner. The flat portion  702  extends laterally between a first set of the tabs  704  and  706  and between a second set of the tabs  708  and  710 , which is longitudinally separated from the first set of the tabs  704  and  706 . 
         [0051]    Referring now to  FIG. 6 , the flat portion  702  includes an opening  712  that aligns with the bore  607  of the bracket  604  when assembled and installed. An opposed pair of the raised tabs (e.g.,  704  and  706 ) may limit or substantially prevent rotation of the bracket  604  on the orientation clip  602  when a torque is applied to the fastening mechanism (e.g., fastening mechanism  810  of  FIG. 8 ), such as when the assembly  600  is installed The fastening mechanism may be configured as or otherwise include, for example, a retainer such as a threaded screw and nut combination, or the like. Limiting or preventing rotation of the bracket  604  when a rotational force is applied to the fastening mechanism and, in turn, the bracket, during installation improves the ease of installation. For example, the orientation clip  602  can help ensure that during installation the bracket  604  is placed in the proper orientation and position relative to the IFS. The orientation clip  602  also can assist in using the support assembly to hold down and maintain a thermal blanket (not shown) in position, as described further below. The bracket  604  and its associated tabs also allow for precise positioning of the sensor assembly on the IFS. 
         [0052]      FIG. 8  is a perspective view of a support assembly  800  with dual brackets in accordance with embodiments disclosed herein, which is configured similar to the dual bracket assembly  406  of  FIG. 4 . The support assembly  800  includes a first support bracket  802  and a second support bracket  804 , each of which supports a sensor assembly  510 . Respective flat portions  806 ,  808  of the two support brackets  802 ,  804  are overlapped on the orientation clip  602 . Alternatively, support brackets  802 ,  804  may be fabricated as a single support bracket. A fastening mechanism  810  attaches the brackets  802 ,  804  to the IFS (not shown). Further details of the fastening mechanism  810  for attaching the support assembly  800  to the IFS may be understood with reference to  FIG. 9 . 
         [0053]      FIG. 9  is a cross-sectional side view of the support assembly  406 ,  800  illustrated in  FIGS. 4 and 8 , installed on an IFS  812 . The left bracket  802  and the right bracket  804  are coupled to the IFS  812  by a fastening mechanism  900  and hold a thermal blanket  901  in place relative to the IFS  812 . This thermal blanket  901  may surround and provide thermal and/or acoustic insulation for some or all of the engine core. The thermal blanket  901 , for example, may shield composite panels of the nacelle from relatively high operating temperatures of the engine core. The thermal blanket  901  may have a flexible sheet-like body with a heat reflective surface that faces the engine. The thermal blanket  901  may include a single layer or multiple layers of materials bound together between face sheets (e.g., metal foil sheets). The thermal blanket  901  may also or alternatively include a core of fibers arranged between the face sheets. The thermal blanket  901  may be constructed from metal and/or any other suitable material. Various thermal blankets are known in the art, and the present disclosure is not limited to any particular thermal blanket types or configurations. Furthermore, the thermal blanket  901  illustrated in  FIG. 9  is optional, and may be included or omitted depending on the aircraft requirements. 
         [0054]    The fastening mechanism  900  includes a location feature attached to the IFS  812 , the location feature including a base portion  902  and a stud or pilot portion  904 . The base portion and stud portion are typically provided as a single one-piece structure, but may be separately provided. When installed, such as illustrated in  FIG. 9 , the stud portion  904  extends outwardly from the plane of the IFS  812  and provides a locating feature or pilot guide that aligns with the bore  807  of each bracket  802 ,  804 . A sleeve portion  906  and head portion  908  fit over the stud  904 . The sleeve portion  906  and head portion  908  may be configured as, for example, a rivet or threaded cap that fits over the stud portion  904 . The stud portion  904  may be threaded, such as when it is provided as a screw or bolt, in which case the sleeve portion  906  will be internally threaded and may be screwed down onto the stud portion  904 . If the stud portion  904  is not threaded, then the sleeve portion  906  fits over the stud portion  904  with a mechanical or friction fit, such as the case with a rivet that is crimped in place to prevent movement. Examples of a suitable base portion and stud portion may include one or more of the fastening products available from Click Bond, Inc. of Carson City, Nev., USA. 
         [0055]    When the sleeve portion  906  and head portion  908  are coupled to the location feature that includes the base portion  902  and stud portion  904 , in an installation configuration such as illustrated in  FIG. 9 , the sleeve portion  906  and head portion  908  are effectively coupled to the IFS  812 . In this way, the fastening mechanism  900  urges both of the brackets  802 ,  804  toward the IFS  812 , and the attachment surface of each bracket is held at a position that is a predetermined distance from the IFS  812  when the support assembly is in the installation configuration. 
         [0056]    The orientation clip  602  may be attached to the thermal blanket  901  by welding, epoxy adhesive, or any other bonding technique known to those skilled in the art. A typical welding technique involves applying electrical energy through the orientation clip  602  to the adjacent surface of the thermal blanket  901 , which melts or otherwise fuses the orientation clip  602  and thermal blanket  901  together at approximately the location of the applied electrical energy. When the orientation clip  602  is fixedly bonded to the IFS  812 , then the clip establishes the location and orientation for mounting brackets  604 , etc., to be mounted to the IFS  812 . 
         [0057]      FIG. 10  is a perspective view of a support assembly  1000  in accordance with an embodiment. The support assembly  1000  includes a bracket  1002  and an attachment portion  1004 . In the  FIG. 10  embodiment, the attachment portion  1004  is configured as an upturned end of the substantially planar bracket  1002 . Two sensor cradles  1006 ,  1008  are attached to opposing sides  1004   a,    1004   b  of the attachment portion  1004 . These sensor cradles  1006  and  1008  are biased so that they will hold or secure in each of the cradles a mounting block  402  or a sensor wire  404 . A fastening mechanism  1010  includes a locating feature, such as a stud or bolt, that aligns the bracket  1002  and holds the bracket  1002  to the IFS (not shown) so that the attachment portion  1004  is a predetermined distance from the IFS. As noted above, the fastening mechanism  1010  can include a stud and rivet combination, as illustrated in  FIG. 10 , or may include a cap and bolt combination, or the like. In  FIG. 10 , a cap portion  1012  and sleeve portion  1014  of the rivet are visible. 
         [0058]      FIG. 11  is a plan view of the bracket  1002  illustrated in  FIG. 10 .  FIG. 11  shows the top planar surface  1104  of the bracket, as well as a bore  1106  sized to receive the locating feature of the fastening mechanism  1010  (see  FIG. 10 ). 
         [0059]      FIG. 12  is a cross-sectional side view of the support assembly  1000  illustrated in  FIG. 10  installed to the IFS  812  and holding a thermal blanket  901  in place. The support assembly  1000  is illustrated in  FIG. 12  in an installed configuration, held to the IFS  812  by a fastening mechanism  900  as described above and illustrated in  FIG. 9 . 
         [0060]      FIG. 13  is a plan view of a support assembly  1300  constructed in accordance with embodiments disclosed herein. The support assembly  1300  includes a substantially planar bracket  1302  with an attachment surface  1304 . A plurality of sensor cradles  1306 ,  1308 ,  1310  and  1312  are attached to the bracket  1302  and receive a variety of sensors  1314 ,  1316 ,  1318 . The support assembly  1300  is coupled to the IFS by one or more fastening mechanisms  1320 ; e.g., through-fasteners. 
         [0061]      FIG. 14  is a cross-sectional side view of the connector assembly illustrated in  FIG. 13 , showing the mounting of the support assembly  1300  to the IFS  812  with the fastening mechanisms  1320 . The fastening mechanisms  1320  each includes a locating feature such as a base portion  1402  and a stud or pilot portion  1404 , which is coupled to the aircraft IFS  812 . The locating feature aligns with a bore (see, e.g.,  FIGS. 15-17 ) of the bracket  1302 . As noted, the base portion  1402  and pilot portion  1404  are typically provided as a single one-piece structure, but may be separately provided. When installed, such as illustrated in  FIG. 14 , the pilot portion  1404  extends outwardly from the plane of the IFS  812  and provides a locating feature or pilot guide that aligns with the bore of the bracket  1302 . In the  FIG. 14  embodiment, a threaded cap or rivet is used to urge the bracket toward the IFS  812 . More particularly, an insert portion  1406  fits into the pilot portion  1404 . The insert portion  1406  is topped at one end with a head portion  1408  and the two may be configured as, for example, a rivet or threaded cap that fits over the pilot portion  1404 . The pilot portion  1404  may be internally threaded, in which case the insert portion  1406  will be threaded and may be screwed down into the pilot portion  1404 . If the insert portion  1406  is not threaded, then the insert portion  1406  fits into the pilot portion  1404  with a mechanical or friction fit, such as the case with a rivet that is crimped in place to prevent movement. Examples of a suitable base portion and stud portion may include one or more of the fastening products available from Click Bond, Inc. of Carson City, Nev., USA. 
         [0062]      FIG. 15  is a cross-sectional side view of a support assembly embodiment that fastens a sensor bracket  1514  to the thermal blanket  901  and the IFS  812  with a fastening mechanism  1502  comprising a stud and nut combination. The structures illustrated in  FIG. 15  are not drawn to scale; rather, some dimensions of the structures are exaggerated for purposes of illustration. A nut  1504  and washer  1506  are threaded onto a stud portion  1508  of a bolt or pilot guide  1510  having a head  1512  at the opposite surface of the IFS  812 . It should be apparent that the nut  1504  can be replaced by a threaded cap. A sensor bracket  1514  is urged toward the IFS  812  and against an orientation clip  1516  by the fastening mechanism  1502 . The sensor bracket  1514  includes a bore  1518  sized to receive the stud portion  1508 , which provides a locating feature of the fastening mechanism  1502 . An optional grommet  1520  may be provided to provide easier placement of the thermal blanket  901  over the stud portion  1508 . 
         [0063]      FIG. 16  is a cross-sectional side view of a support assembly embodiment for use without a thermal blanket, attached to the IFS  812  with a stud and nut combination. The structures illustrated in  FIG. 16  are not drawn to scale; rather, some dimensions of the structures are exaggerated for purposes of illustration. The support assembly is attached to the IFS  812  with a fastening mechanism  1602  including a stud and nut combination. A nut  1604  and washer  1606  are threaded onto a stud portion  1608  of a bolt or pilot guide  1610  having a head  1612  at the opposite surface of the IFS  812 . A bracket  1614  is urged toward the IFS  812  by the fastening mechanism  1602 . The bracket  1614  includes a bore  1618  sized to receive the stud portion  1608 , which provides a locating feature of the fastening mechanism  1602 . 
         [0064]      FIG. 17  is a cross-sectional side view of a support assembly embodiment for use without a thermal blanket, attached to the IFS  812  with a fastening mechanism comprising a rivet configuration. The structures illustrated in  FIG. 17  are not drawn to scale; rather, some dimensions of the structures are exaggerated for purposes of illustration. The support assembly is attached to the IFS  812  with a fastening mechanism  1702  configured as a rivet combination. A rivet cap  1704  is crimped onto a rivet stud portion  1708  having a head  1710  at the opposite surface of the IFS. As known to those skilled in the art, the rivet combination  1702  may be installed by mechanically deforming an end of the stud portion  1708 , or through other similar crimping techniques for installing a rivet. A bracket  1712  is urged toward the IFS  812  by the fastening mechanism rivet  1702 . The bracket  1712  includes a bore  1718  sized to receive the rivet stud portion  1708 , which provides a locating feature of the fastening mechanism  1702 . 
         [0065]    Other variations are within the spirit of the present invention. Thus, while the invention is susceptible to various modifications and alternative constructions, certain illustrated embodiments thereof are shown in the drawings and have been described above in detail. It should be understood, however, that there is no intention to limit the invention to the specific form or forms disclosed, but on the contrary, the intention is to cover all modifications, alternative constructions, and equivalents falling within the spirit and scope of the invention, as defined in the appended claims 
         [0066]    The use of the terms “a” and “an” and “the” and similar referents in the context of describing the invention (especially in the context of the following claims) are to be construed to cover both the singular and the plural, unless otherwise indicated herein or clearly contradicted by context. The terms “comprising,” “having,” “including,” and “containing” are to be construed as open-ended terms (i.e., meaning “including, but not limited to,”) unless otherwise noted. The term “connected” is to be construed as partly or wholly contained within, attached to, or joined together, even if there is something intervening. Recitation of ranges of values herein are merely intended to serve as a shorthand method of referring individually to each separate value falling within the range, unless otherwise indicated herein, and each separate value is incorporated into the specification as if it were individually recited herein. All methods described herein can be performed in any suitable order unless otherwise indicated herein or otherwise clearly contradicted by context. The use of any and all examples, or exemplary language (e.g., “such as”) provided herein, is intended merely to better illuminate embodiments of the invention and does not pose a limitation on the scope of the invention unless otherwise claimed. No language in the specification should be construed as indicating any non-claimed element as essential to the practice of the invention. 
         [0067]    Preferred embodiments of this invention are described herein, including the best mode known to the inventors for carrying out the invention. Variations of those preferred embodiments may become apparent to those of ordinary skill in the art upon reading the foregoing description. The inventors expect skilled artisans to employ such variations as appropriate, and the inventors intend for the invention to be practiced otherwise than as specifically described herein. Accordingly, this invention includes all modifications and equivalents of the subject matter recited in the claims appended hereto as permitted by applicable law. Moreover, any combination of the above-described elements in all possible variations thereof is encompassed by the invention unless otherwise indicated herein or otherwise clearly contradicted by context. 
         [0068]    All references, including publications, patent applications, and patents, cited herein are hereby incorporated by reference to the same extent as if each reference were individually and specifically indicated to be incorporated by reference and were set forth in its entirety herein.