Abstract:
Devices and methods for stabilizing a structural component are provided. The devices may include a main body component, a pair of opposed stabilization feet engageable with opposed regions of the structural component, a pair of coaxially disposed and reciprocal rectilinearly movable support shafts coupling the stabilization feet to the main body component, and an actuator assembly for rectilinearly moving the support shafts opposite to one another which in turn moves the stabilization feet between retracted and extended positions relative to the main body component. In use, the device may be positioned between opposed flanges of a structural component so as to stabilize the component and facilitate automated assembly processes.

Description:
FIELD 
       [0001]    The embodiments disclosed herein relate generally to devices and methods which stabilize a structural component during assembly with other parts, e.g., so as to facilitate automated assembly processes. 
       BACKGROUND 
       [0002]    The planning processes for structural assembly is a critical period during fabrication since it has a permanent effect over the cost and quality of the finished product. In this regard, while automobiles and ships use different types of welding for structural fabrication, aeronautical structures require fabrication using rivets and bolts due to the high stresses and strains to which they are subjected during use. In order to maintain the structural integrity of segments that constitute the airframe of an aircraft, substantial attention must be given to the drilling process and insertion of rivets for joining various component parts. 
         [0003]    The current practice for assembling aircraft structural components is to employ a number of steps which in turn increase the time needed to achieve full assembly. Moreover, the current practice of assembling aircraft structural components requires a large number of manual activities which in turn increases time, manufacturing cycle and the number of non-conforming assemblies during the process. For example, current aircraft assembly processes typically involve a pre-assembly of the components to allow for drilling, following which the components are disassembled, deburred, cleaned and then re-assembled with final fasteners (e.g., rivets and/or bolts). 
         [0004]    An assembly process whereby the various component parts could be pre-aligned for automated drilling and final assembly without intermediate disassembly would thereby reduce the number of manual activities and cycle time, thereby increasing product quality and hence reduce overall production costs. In order to accomplish this type of a more efficient assembly process requires that the drilling of the component parts be accomplished reliably without creating swarf between the parts to be joined together. In such a manner, therefore, the swarf-free drilling of components could promote the direct joining of the components by rivets and/or bolts thereby avoiding the conventional process of disassembly and cleaning of the components. 
         [0005]    In order to achieve the more efficient process as described above, however, it is necessary that the component parts be stabilized to prevent deflection due to drilling forces which could otherwise result in swarth being trapped between components to be joined. What has been needed in this art, therefore, are stabilization devices and methods whereby component parts may be reliably handled by robotics to allow for the automated drilling and final assembly of parts without necessarily disassembling the parts for cleaning and/or deburring. It is towards fulfilling such needs that the presently claimed invention is directed. 
       SUMMARY 
       [0006]    In general, the embodiments disclosed herein are directed toward devices and methods which stabilize a structural component during assembly with other parts, e.g., so as to facilitate automated assembly processes. According to some embodiments, the stabilization device will include a main body component, a pair of opposed stabilization feet engageable with opposed regions of the structural component, a pair of coaxially disposed and reciprocal rectilinearly movable support shafts coupling the stabilization feet to the main body component, and an actuator assembly for rectilinearly moving the support shafts opposite to one another which in turn moves the stabilization feet between retracted and extended positions relative to the main body component. 
         [0007]    According to certain embodiments, the stabilization feet may comprise an engagement surface at a terminal end therefore for engaging a respective one of the opposed regions of the structural component. Elongate recessed channels extending rearwardly from the engagement surface may be formed in the stabilization feet (e.g., so as to accommodate a drill bit to allow drilling of holes through a flange of the structural component and another part mated therewith). 
         [0008]    The main body component according to certain embodiments may comprise an expansion chamber which houses opposed proximal ends of the support shafts, and wherein the actuator assembly comprises an actuator rod positioned substantially perpendicular to the support shafts and having a terminal engagement end which operably interacts with the opposed proximal ends of the shafts to rectilinearly move the shafts outwardly and inwardly relative to one in dependence upon a respective direction of turning movement applied to the actuator rod. The opposed ends of the shafts may comprise opposed beveled cam surfaces, wherein the terminal engagement end of the actuator rod is engageable with the cam surfaces. The actuator rod may be threadably coupled to the main body member so as to move the terminal engagement end of the actuator rod into and out of engagement with the cam surfaces depending on the direction of turning movement applied to the actuator rod (e.g., via a T-handle at an opposite end thereof). Springs (e.g., compression springs) may operatively associated with each of the support shafts for biasing the support shafts in a rectilinear inward direction relative to one another. 
         [0009]    Certain embodiments will include a base plate attached to the main body member, and a clamp assembly operatively connected to the base plate for positionally clamping the base plate to the structural component. The base plate may, for example, be sized and configured to be accepted within an opening formed in the structural component (e.g., an opening formed in an aircraft wing rib component). In such a case, the clamp assembly may include a clamp arm which spans the opening formed in the structural component. Each opposed end of the clamp arm may include a clamp pad which may be forcibly seated against a surface region of the structural component adjacent to the opening. A set screw may be provided for removably connecting the clamp arm to the base plate. 
         [0010]    The devices as described herein are especially adapted for aircraft fabrication processes (e.g., so as to allow at least some automated processing to occur, such as drilling of parts to be joined to one another). In this regard, the stabilization device may be clamped to the structural component such that the opposed stabilization feet are engaged with respective regions of opposed flanges of the structural component. 
         [0011]    As noted above, each of the stabilization feet may be provided with spaced-apart elongate recessed channels extending rearwardly from engagement surfaces of the stabilization feet which engage with the respective regions of the opposed flanges. Thus, by positioning a part to be joined with the structural component in adjacent contact each of the opposed flanges, holes may be drilled through the part and the flange of the structural component in alignment with the recessed channels such that the recessed channels accommodate a terminal portion of the drill bit during such operation. 
         [0012]    A base plate of the device may therefore be positioned within an opening formed in the structural member (e.g., an opening formed in an aircraft wing rib component) such that the clamp arm which spans the opening may be clamped to the structural component (e.g., by manipulating a set screw which connects the clamp arm to the base plate). Operating an actuator assembly of the device will thereby move the support shafts in opposite outward directions relative to one another to thereby cause the stabilization feet to engage a respective one of the opposed flanges of the structural member, whereby the component is stabilized. 
         [0013]    These and other aspects and advantages of the present invention will become more clear after careful consideration is given to the following detailed description of the preferred exemplary embodiments thereof. 
     
    
     
       BRIEF DESCRIPTION OF ACCOMPANYING DRAWINGS 
         [0014]    The disclosed embodiments of the present invention will be better and more completely understood by referring to the following detailed description of exemplary non-limiting illustrative embodiments in conjunction with the drawings of which: 
           [0015]      FIG. 1  is a top perspective view of a wing rib component associated with an aircraft airfoil structure which has been stabilized for assembly by a number of stabilization devices according to an embodiment of the present invention; 
           [0016]      FIG. 2  is a bottom perspective view of the wing rib component and stabilization devices as shown in  FIG. 1 ; 
           [0017]      FIG. 3  is an enlarged left side perspective view of a stabilization device according to an embodiment of the present invention; 
           [0018]      FIG. 4  is an enlarged right side perspective view of the stabilization device depicted in  FIG. 3 ; 
           [0019]      FIG. 5  is a partial cross-sectional elevational view of the stabilization device depicted in  FIG. 4  as taken along lines  5 - 5  therein depicted in a fully extended state; and 
           [0020]      FIG. 6  is a partial cross-sectional elevational view of the stabilization device similar to  FIG. 5  but depicted in a fully retracted state. 
       
    
    
     DETAILED DESCRIPTION 
       [0021]    Accompanying  FIGS. 1 and 2  depict a wing rib component WRC of an aircraft airfoil in combination with a number of stabilization devices  10  according to an embodiment of the invention. It will be observed that the wing rib component WRC will include lengthwise openings  12  and opposed lengthwise extending flanges  14   a ,  14   b . During the fabrication process, another component of the airfoil, e.g., strips of aluminum skin (portions of which are depicted in  FIG. 1  by reference numerals  16   a ,  16   b ) are mated against the flanges  14   a ,  14   b , respectively. The strips of aluminum skin  16   a ,  16   b  and flanges  14   a ,  14   b  are thereby drilled to form suitable receiving holes (a few of which are depicted in  FIG. 1  by reference numeral  18 ) for placement of rivets by which the strips of skin  16   a ,  16   b  and the flanges  14   a ,  14   b  are joined one to another. In order to provide swarth-free drilling of the holes  18 , the stabilization devices  10  are provided so as to resist deformation forces acing on the flanges  14   a ,  14   b  by means of a drill bit (not shown) which could otherwise tend to forcibly separate the flanges  14   a ,  14   b  from the skins  16   a ,  16   b  thereby allowing swarth to be deposited therebetween. 
         [0022]    An exemplary stabilization device  10  is perhaps more clearly depicted in  FIG. 3 . As is shown, the stabilization device  10  is comprised generally of a main body member  20  and a pair of opposed stabilization feet  22   a ,  22   b . As will be described in greater detail below, the feet  22   a ,  22   b  are operably joined to the main body member  20  by rectilinearly reciprocal moveable support shafts  24   a ,  24   b , respectively. 
         [0023]    The main body member  20  includes an expansion chamber  26  positioned on a central base plate  28 . As can be seen from  FIG. 2 , the base plate  28  includes opposed arcuate edges  28   a ,  28   b  which conformably mate to the openings  12  provided in the wing rib component WRC. A clamp arm  30  is removably connected to the base plate  28  by means of a set screw  32 . The opposed ends of the clamp arm  30  are provided with a respective clamp pad  30   a ,  30   b . As shown in  FIG. 2 , the clamp arms  30  are of sufficient length to span the openings  12  so that each of the clamp pads  30   a ,  30   b  may be forcibly seated against a surface region of the wing rib component WRC. In such a manner therefore, the clamp arms  30  securely yet removably attach stabilization devices  10  to the wing rib component WRC. 
         [0024]    Each of the feet  22   a ,  22   b  includes a downwardly and outwardly (relative to the main body member  20 ) sloped surface  22   a - 1 ,  22   b - 1  which terminates in a substantially planar perpendicular engagement surface  22   a - 2 ,  22   b - 2  which is adapted to engage with an interior surface region of the flanges  14   a ,  14   b  of the wing rib component WRC. The engagement surface  22   a - 2 ,  22   b - 2  includes a number of interiorly recessed notches  22   a - 3 ,  22   b - 3  each having a sufficient depth dimension so as to receive therein a portion of the drill bit when drilling the holes  19  through the skins  16   a ,  16   b , respectively. Thus, by virtue of the recessed notches  22   a - 3 ,  22   b - 3 , the engagement surfaces  22   a - 2 ,  22   b - 2  of the feet  22   a ,  22   b  can be maintained in forcible contact with the interior surfaces of the flanges  14   a ,  14   b , respectively. As such, the feet  22   a ,  22   b  provide a secure foundation against which the flanges  14   a ,  14   b  are pressed to prevent separation of the flanges  14   a ,  14   b  from the skins  16   a ,  16   b  when the holes  18  are drilled therethrough. Each of the feet  22   a ,  22   b  may also include generally U-shaped recesses  22   a - 4 ,  22   b - 4  which are aligned with similar recesses  14 - 1 ,  14 - 2  formed in the wing rib component WRC. 
         [0025]    Accompanying  FIGS. 5 and 6  show the internal structural mechanisms associated with an actuator assembly  35  housed within the expansion chamber  26  of the main body member  20  which allow a spreading to be exerted by the feet  22   a ,  22   b  against the respective flanges  14   a ,  14   b . Specifically, each proximal end of the coaxially opposed shafts  24   a ,  24   b  includes oppositely disposed beveled cam surface  25   a ,  25   b . A threaded actuator rod  40  is threadably engaged with the main body member  20  and is positioned substantially perpendicular to the support shafts  24   a ,  24   b . The actuator rod also includes a terminal engagement end  40   a  which is capable of bearing against the cam surfaces  25   a  and  25   b  of the shafts  24   a ,  24   b . A handle  42  is connected substantially perpendicular to the actuator rod  40  at the upper end opposite to the engagement end  40   a  thereof so as to form a T-shaped structure that can be manually manipulated to impart turning movement in a desired direction to the actuator rod  40 . 
         [0026]    The support shafts  24   a ,  24   b  includes coaxially positioned compression springs  50   a ,  50   b  acting between washers  52   a ,  52   b  fixed to the shafts  24   a ,  24   b , respectively, and an opposed interior region of the expansion chamber  26 . 
         [0027]    Turning movement in a clockwise direction (assuming a standard right handed thread on the actuator rod  40 ) applied to the handle  42  will in turn cause the engagement end  40   a  to be moved downwardly into engagement with the cam surfaces  25   a ,  25   b  of the shafts  24   a ,  24   b , respectively. Continued turning movement applied to the rod  40  will thereby cause the engagement end  40   a  to progressively be lowered (i.e., in the direction of arrow A 1  in  FIG. 5 ) which in turn causes each of the shafts  24   a ,  24   b  to be coaxially displaced in opposite directions (i.e., in the directions of arrows A 2  and A 3  in  FIG. 5 ). This coaxial displacement of the shafts  24   a ,  24   b  will thereby cause the feet  22   a ,  22   b  connected at the distal ends thereof to be spread apart thereby force-loading the compression springs  50   a ,  50   b , respectively, to thus forcibly maintain the feet  22   a ,  22   b  against the inside of the flanges  14   a ,  14   b  of the wing rib component WRC. 
         [0028]    When it is desired to remove the stabilization assembly  10  from the wing rib component WRC, an turning force in an opposite direction to that described above may be applied to the handle  42  to thereby raise the engagement end  40   a  of the actuator rod  40  (i.e., in a direction opposite to arrow A 1  in  FIG. 5 ) relative to the cam surfaces  25   a ,  25   b . This in turn causes the shafts  24   a ,  24   b  to be retracted towards one another (i.e., in directions opposite to arrows A 2  and A 3  in  FIG. 5 ) under the influence of the bias force provided by the compression springs  50   a ,  50   b , respectively (i.e., since the force of the springs  50   a ,  50   b  will then be unloading). 
         [0029]    Accompanying  FIG. 5  the shafts  24   a ,  24   b  in fully extended state (i.e., since the engagement end  40   a  is in a maximum downward extent relative to the cam surfaces  25   a ,  25   b  of the shafts  24   a ,  24   b , respectively), whereas accompanying  FIG. 6  shows the shafts  24   a ,  24   b  in a fully retracted state (i.e., since the engagement end  40   a  is fully disengaged from the cam surfaces  25   a ,  25   b ). When in a state as depicted in  FIG. 5 , the feet  22   a ,  22   b  will exert maximum compressive force against the inside of the flanges  14   a ,  14   b , whereas when in a state depicted in  FIG. 6 , the feet  22   a ,  22   b  will be physically separated from the flanges  14   a ,  14   b  thereby permitting removal of the stabilization device  10  from the wing rib component WRC. 
         [0030]    Although the stabilization device  10  has been described above as being employed in combination with a wing rib component WRC, it will be understood that such a description is merely an exemplary embodiment of the invention. Thus, other embodiments of the invention could be provided so as to facility the assembly of other components associated with an aircraft or with any other structure, e.g., automobile, ship or the like. 
         [0031]    It will therefore be understood that the description provided herein is presently considered to be the most practical and preferred embodiment of the invention. Thus, the invention is not to be limited to the disclosed embodiment, but on the contrary, is intended to cover various modifications and equivalent arrangements included within the spirit and scope thereof.