Abstract:
A system for extracting an assembly component from an assembly uses an extractor that applies a gripping force around a perimeter of the assembly component, a coupler that applies an extraction force to the extractor and a tensioner fastened to the coupler that generates the extraction force, the extraction force causing the assembly component to slide out of the assembly. The tensioner applies an extraction force to the extractor which pulls the assembly component from the assembly.

Description:
FIELD 
       [0001]    This disclosure relates generally to manufacturing operations and more particularly to extracting a reusable assembly component from an assembly used in an aircraft. 
       BACKGROUND 
       [0002]    Modern transportation machines have migrated away from assemblies made of metal, such as aluminum to composite materials to reduce weight and increase strength. The manufacture of these composite materials involves the use of reusable components that may be partially or wholly surrounded by the finished assembly. Removing these reusable components may create a hazard if an attachment slips during removal but alternatively may damage the reusable component if too much gripping force is applied. 
       SUMMARY 
       [0003]    In aspect of the disclosure, an extractor is used with an assembly component where the assembly component has a hollow cross-sectional shape with an exterior surface and an interior surface extending about a longitudinal axis. The extractor includes a sleeve for fitment about the exterior surface of the assembly component and includes an interior wall substantially matching the cross-sectional shape of the exterior surface of the assembly component and having a taper along the longitudinal axis. The extractor also includes a plug for receipt within the assembly component having an exterior wall substantially matching the cross-sectional shape of the interior surface of the assembly component and having a taper along the longitudinal axis. The extractor further includes a coupler for transferring a pulling force to the sleeve to cause the sleeve to shift along the longitudinal axis and cause the taper of the sleeve and plug to reduce a gap there between. 
         [0004]    In another aspect of the disclosure, a method of extracting an assembly component from an assembly where the assembly component has a hollow cross-sectional shape with an exterior surface and an interior surface extending about a longitudinal axis includes placing a sleeve over the assembly component, the sleeve having an interior wall substantially matching the cross-sectional shape of the exterior surface of the assembly component. The method also includes placing a plug into an interior of the assembly component, the plug having an exterior wall substantially matching the cross-sectional shape of the interior surface of the assembly component. The method further includes moving the sleeve over the plug to reduce a gap between interior wall of the sleeve and the exterior wall of the plug and applying a force to the sleeve in a direction of extraction to remove the assembly component from the assembly. 
         [0005]    In yet another aspect of the disclosure, a system is used for extracting an assembly component from an assembly where the assembly component having a hollow cross-sectional shape with an exterior surface and an interior surface extending about a longitudinal axis. The system includes an extractor that applies a gripping force around a perimeter of the assembly component, the extractor including a coupler that receives an extraction force and a tensioner fastened to the coupler that generates the extraction force so that the extraction force causes the assembly component to release from the assembly. 
         [0006]    The features, functions, and advantages that have been discussed can be achieved independently in various embodiments or may be combined in yet other embodiments further details of which can be seen with reference to the following description and drawings. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]    For a more complete understanding of the disclosed methods and apparatuses, reference should be made to the embodiment illustrated in greater detail on the accompanying drawings, wherein: 
           [0008]      FIG. 1  is a perspective view illustrating an embodiment of an extractor coupled to an assembly component and assembly in accordance with the current disclosure; 
           [0009]      FIG. 2  is a top view of an exemplary plug that is part of the extractor; 
           [0010]      FIG. 3  is a front view of the exemplary plug of  FIG. 2 ; 
           [0011]      FIG. 4  is a side view of the exemplary plug of  FIG. 2 ; 
           [0012]      FIG. 5  is a top view of an exemplary sleeve that is part of the extractor; 
           [0013]      FIG. 6  is a front view of the exemplary sleeve of  FIG. 5 ; 
           [0014]      FIG. 7  is a side view of the exemplary sleeve of  FIG. 5 ; 
           [0015]      FIG. 8  is a top view of an exemplary collar that may be used with the extractor; 
           [0016]      FIG. 9  is a front view of the exemplary collar of  FIG. 8 ; 
           [0017]      FIG. 10  is a side view of the exemplary collar of  FIG. 8 ; 
           [0018]      FIG. 11  is a top view of an embodiment of the extractor of  FIG. 1 ; 
           [0019]      FIG. 12  is a top view of an alternate configuration of the extractor  104  shown in  FIG. 11 ; 
           [0020]      FIG. 13  is a top view of an alternate embodiment of the extractor  104  using the collar; and 
           [0021]      FIG. 14  is an illustration of operations performed by one embodiment that uses an extractor to remove an assembly component from an assembly in accordance with the current disclosure. 
       
    
    
       [0022]    It should be understood that the drawings are not necessarily to scale and that the disclosed embodiments are sometimes illustrated diagrammatically and in partial views. In certain instances, details which are not necessary for an understanding of the disclosed methods and apparatuses or which render other details difficult to perceive may have been omitted. It should be understood, of course, that this disclosure is not limited to the particular embodiments illustrated herein. 
       DETAILED DESCRIPTION 
       [0023]    An assembly component  100  may be used to create a feature  101 , such as a groove or channel in an assembly  102 . In various embodiments, the feature  101  may increase the stiffness of the assembly  102 , may create a channel for cables or pipes, or both. In one embodiment, the assembly  102  may be stringer for an airplane wing or fuselage (not depicted). The assembly component  100  may be made of a flexible material, such as rubber or another elastic material that is rigid enough to hold its shape during the manufacture of the assembly  102 , but that is also able to deform sufficiently to allow the assembly component  100  to be extracted the manufacturing operation is finished. In other embodiments, the assembly component  100  may be more rigid, made of materials such as metal or plastic. The assembly component  100  may be in various shapes to suit the need of the assembly operation and may be a closed tube with various cross sections, such as a circle, square or rhombus, or may be an open structure such as a half pipe or gutter shape. The assembly component generally has a uniform cross-sectional shape along a longitudinal axis  105  and has an exterior surface and an interior surface. In embodiments where the assembly component  100  is reusable, it is desirable to minimize damage to the assembly component  100  during the extraction process. The assembly  102  may be manufactured using a form  103 . In an embodiment, the assembly  102  may be a composite material including carbon fiber or other high tensile strength materials. 
         [0024]    In order to accomplish extraction while minimizing the potential for damage, an extractor  104  may be used to provide an even gripping pressure around a perimeter of the assembly component  100  so that an extraction force  106  can be transferred via the extractor  104  to the assembly component  100 . In an embodiment, the extraction force  106  may be generated by a tensioner  108  such as a winch, a block and tackle, a motorized cart, or other mechanism capable of generating the force necessary to overcome frictional forces that exist between the assembly component  100  and the assembly  102  after completion of the manufacturing process that creates the assembly  102 . In an embodiment, the tensioner  108  may be coupled to the extractor  104  via a rope or cable  110 . 
         [0025]    The extractor  104 , in an exemplary embodiment, may have several components. The first, a plug  120 , is illustrated in top view, front view and side view in  FIGS. 2, 3, and 4 , respectively. The top view of  FIG. 2  shows a column  122 . In an embodiment, the column  122  may be a frustum of 3D object matching a shape of the assembly component  100 . For example, if the assembly component  100  is square, the column  122  may be a frustum of a square pyramid. If the assembly component is round, the column  122  may be a frustum of a cone. If the assembly component  100  is a rhombus, as shown in the illustrated embodiment, the column  122  may be the frustum of a rhomboid pyramid. A narrow dimension  123  may be slightly smaller than an opening of the assembly component  100  while the opposite, larger, end may be the same size or slightly larger than the opening of the assembly component  100 . The plug  120  may include a flange  124  and threaded holes  126 , discussed in more detail below. In one embodiment, the plug  120  may have a hollow core  128  to reduce the weight and ease handling of the plug  120 . However, in other embodiments, the plug  120  may be solid. 
         [0026]    The extractor  104  may also include a sleeve  130  illustrated by top, front, and side views in  FIGS. 5, 6, and 7 , respectively. The sleeve  130  may be a hollow column  132  with an interior wall structure  134  defining a tapered center core  135  along an axis  136 . The axis  136  may lie along a line of symmetry of the tapered center core  135  and defines an ideal direction of force application to extract the assembly component  100  from the assembly  102 . The interior wall structure  134  may be congruent, or at least geometrically similar, to the column  122  of the plug  120  so that the plug  120  can nest inside the interior wall structure  134  of the sleeve  130 . In an embodiment, threaded holes  138  may be used to attach a coupler used to apply force to the sleeve, as discussed below with respect to  FIG. 11 . 
         [0027]    In various embodiments, the extractor  104  may be made of aluminum, plastic, stainless steel, or another material that can be suitably milled, cast, or 3D printed and provides sufficient strength to withstand the forces required for extracting the assembly component  100 . In some applications, the chemistry of the assembly  102  and/or specific manufacturing requirements may limit the material selection for the extractor  104  to those that are compatible with the assembly  102  and the manufacturing process. In the illustrated embodiment where the assembly  102  is an airplane wing stringer, the extractor  104  may be made of aluminum. 
         [0028]      FIGS. 8, 9 and 10  illustrate top, front and side views, respectively, of a collar  140  with an opening  142 . The collar  140  may be placed behind the sleeve  130  and attached to a tensioner  108  to provide a generally uniform force against the sleeve during the extraction process. The use of the collar  140  is discussed more below with respect to  FIG. 13 . 
         [0029]    The assembled extractor  104  is illustrated in  FIG. 11 . The sleeve  130  is first placed over the assembly component  100  pushed far enough above an end of the assembly component so that the plug  120  may be inserted into the assembly component  100 . For example, the plug may be inserted until the flange  124  abuts the end of the assembly component  100 . The sleeve  130  may then be moved toward the plug  120  so that the facing walls of the interior wall structure  134  of the sleeve  130  and the column  122  of the plug  120  exert a gripping force on the plug  120 .  FIG. 11  also illustrates an interior surface  156  and an exterior surface  158  of the assembly component  100 . 
         [0030]    A coupler  152 , shown in the embodiment illustrated in  FIG. 11  uses an eye bolt screwed into the threaded holes  138  to apply an extraction force collinear with the axis  136 . In an embodiment, additional couplers  152  may be added to allow more symmetric application of force to the sleeve  130 , as shown in  FIG. 1 . In other embodiments a threaded rod (not depicted) may be configured as the coupler  152 . A rope or cable  110  may be attached between the coupler  152  and a tensioner  108  to transfer the extraction force  106  to the extractor  104  and ultimately to the assembly component  100 . 
         [0031]    During the extraction operation, the sleeve  130  and plug  120  may become stuck together due to the mechanical wedging of the sleeve  130  and plug  120 . In order to simplify separating the two components, release screws  154  are shown screwed into threaded holes  126 . The release screws  154  may be further advanced to force the sleeve  130  back away from the plug  120  after the extraction process is completed to allow disassembly of the extractor  104 . 
         [0032]    In an embodiment, a generally uniform gap  150  is formed between the sleeve  130  and plug  120 , which in various embodiments is greater than zero and less than a wall thickness of the assembly component  100 . If the gap  150  is too large, not enough compression force, or gripping force, is exerted and the assembly component  100  will slip out of the extractor  104 . If the gap  150  is too small, the assembly component  100  may be crushed or tear and become unusable for future assembly operations. In an embodiment, the gap  150  is a desired dimension when the sleeve  130  contacts the flange  124 . Also to reduce the risk of damage to the assembly component  100  during the extraction operation, the facing surfaces of the interior wall structure  134  and column  122  may be generally smooth and absent a pattern such as knurling or ridges that might score or weaken the assembly component  100 . However, such patterning may be desirable to increase the frictional force exerted on the assembly component  100  for some materials that may be used for the assembly component  100 . 
         [0033]    Turning to  FIG. 12 , an alternate embodiment is shown where the release screws  154  are adjusted to a known offset that sets a distance between the sleeve  130  and the flange  124 , thereby setting the gap  150  to a desired dimension. By setting the release screws  154  in this fashion, the gap  150  can be adjusted to accommodate different assembly component materials and thicknesses. 
         [0034]    Yet another embodiment of the extractor  104  is illustrated in  FIG. 13 . In this embodiment, instead of a threaded coupler  152 , an alternate coupler in the form of a collar  140  is placed against the sleeve  130  on a side opposite the plug  120  so that the collar rests against this back side of the sleeve  130 . One or more ropes or cables  110  may be attached to the collar  140  to provide an even force that moves the sleeve  130  over the plug  120 . 
         [0035]      FIG. 14  is a flowchart of a method  200  of extracting an assembly component  100  from an assembly  102 . Optionally, at block  202 , a collar  140  may be placed over the assembly component  100 , when the collar  140  is used to apply force to the sleeve  130  instead of a threaded coupler  152 . At block  204 , the sleeve  130  may be placed over the assembly component  100  so that, at block  206 , the plug  120  may be inserted into the assembly component  100 . In an embodiment, the plug  120  may be inserted until a flange  124  of the plug  120  contacts an end of the assembly component  100 . 
         [0036]    At block  208 , the sleeve  130  is moved toward the plug  120  so that the facing surfaces of the sleeve  130  and plug  120  wedge together against outer and inner surfaces, respectively, of the assembly component  100 . In an embodiment, the sleeve  130  may be moved toward the plug  120  so that the sleeve  130  contacts the flange  124 , setting a gap  150  between the interior wall structure  134  and the column  122 . 
         [0037]    At block  210 , an extraction force  106  may be applied to the sleeve  130  collinear with the axis  136  of the sleeve  130  so that the assembly component  100  is drawn out of the assembly  102 . Different embodiments of tensioner  108  may be used to apply the extraction force  106 . In one embodiment, a motorized cart (not depicted) may be driven along a course that draws the assembly component  100  out of the assembly  102 . In another embodiment, the force may be applied by a winch or a block and tackle mounted at a fixed point. 
         [0038]    A determination is made at block  212  whether the assembly component  100  has been fully extracted. If not, the ‘no’ branch is taken to block  214  and the application of the extraction force  106  is continued, returning to block  212 . If, at block  212 , the assembly component  100  is fully removed from the assembly  102 , the ‘yes’ branch may be taken to block  216 . 
         [0039]    At block  216 , the extractor  104  may be disassembled into the component parts of the sleeve  130  and plug  120 . In an embodiment, the release screws  154  may be screwed through the flange  124  to force the sleeve  130  away from the plug  120 , releasing the assembly component  100 . In an embodiment, the extractor  104  may be considered part of a system that includes a coupler  152  and a tensioner  108 . The extractor  104  is used to apply a uniform gripping force around a perimeter of the assembly component  100  using overlapping sleeve  130  and plug  120  components. 
         [0040]    The use of an extractor  104  for the removal of the assembly component  100  from the assembly  102  benefits the manufacturers of composite materials by increasing productivity using a simple, repeatable process for assembly component extraction. At the same time, the use of the extractor  104  minimizes damage to the assembly component  100 , prolonging its life and reducing overall manufacturing costs. 
         [0041]    While only certain embodiments have been set forth, alternatives and modifications will be apparent from the above description to those skilled in the art. These and other alternatives are considered equivalents and within the spirit and scope of this disclosure and the appended claims.