Abstract:
A stiffener system includes a stiffener and a fastener means. The stiffener includes an extruded body that includes a plurality of projections. The stiffener couples to the apparatus to facilitate increasing a structural integrity of the apparatus. The fastener means secures the stiffener to the apparatus.

Description:
BACKGROUND OF THE INVENTION 
     This invention relates generally to structural support devices and more particularly, methods and apparatus for providing structural support to an apparatus. 
     As machinery operates, components coupled to the machinery may be subjected to vibrational stresses. Over time, continued exposure to vibrational stresses may cause damage to such components. 
     To facilitate reducing the effects of vibrational stresses, at least some known machinery components include structural supports. For example, within some known gas turbine engines, tubular components are reinforced with external brackets. Other known tubular components are reinforced with complex damping systems. However, such external supports are expensive and may be difficult to couple to attached components. Furthermore, depending on a length of the component, as the component is distressed, bending moments may be generated between the external support structures over time, such bending moments may weaken the components and eventually reduce a useful life of the component. 
     BRIEF SUMMARY OF THE INVENTION 
     In one aspect of the invention a stiffener for an apparatus is provided. The stiffener includes a body including a plurality of projections. The stiffener couples to the apparatus such that the projections circumscribe the apparatus and such that the stiffener facilitates increasing a stiffness-to-mass ratio of the apparatus. 
     In another aspect of the invention, a stiffener system including a stiffener and a fastening means is provided. The stiffener includes an extruded body that includes a plurality of projections. The stiffener couples to the apparatus to facilitate increasing a stiffness-to-mass ratio of the apparatus. The fastener means secures the stiffener to the apparatus. 
     In a further aspect, a method for increasing a stiffness-to-mass ratio of the apparatus is provided. The method includes the steps of providing a stiffener including an extruded body including a plurality of projections and coupling the stiffener to the apparatus such that the projections circumscribe the apparatus to facilitate increasing a stiffness-to-mass ratio of the apparatus. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     FIG. 1 is a perspective view of an exemplary embodiment of a stiffener; 
     FIG. 2 is an alternative view of the stiffener shown in FIG. 1 coupled to an apparatus; and 
     FIG. 3 is a cross-sectional view of an alternative embodiment of a stiffener coupled to an apparatus. 
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     FIG. 1 is a perspective view of an exemplary embodiment of a stiffener  10 . In the exemplary embodiment, stiffener  10  is extruded and is corrugated, such that stiffener  10  includes a plurality of projections  12  extending from a body  14 . In one embodiment, projections  12  are formed integrally with stiffener body  14 . Stiffener  10  includes a bottom surface  16  and an oppositely disposed top surface  18  that extends substantially parallel to bottom surface  16 . Stiffener  10  has a thickness  20  that is measured between bottom surface  16  and top surface  18 . Thickness  20  is variably selected depending on an intended use of stiffener  10  and is selected to ensure stiffener  10  has a pre-determined flexibility for the intended use. Stiffener  10  also has a length  22  and a width  24 . Stiffener length  22  and width  24  are both variably selected depending on the intended use of stiffener  10 . In one embodiment, stiffener  10  is formed from a single sheet of metallic material. In another embodiment, stiffener  10  is formed from a non-metallic material. Alternatively, stiffener  10  is formed from a plurality of sheets connected together. 
     In the exemplary embodiment, projections  12  are substantially identical and extend substantially perpendicularly from stiffener bottom surface  16 . More specifically, projections  12  are arranged in a cyclic pattern and extend lengthwise and widthwise across stiffener  10  in a longitudinal-axial configuration. Adjacent projections  12  are substantially parallel to each other, and each projection  12  includes a bottom surface  26 , a top surface  28 , and a pair of sidewalls  30  and  32 . In the exemplary embodiment, projection  12  top surface  28  and sidewalls  30  and  32  define a substantially rectangular cross-sectional profile. Alternatively, projection  12  defines a non-rectangular cross-sectional profile. For example, projection  12  defines, but is not limited to defining, at least one of a circular, a triangular, and a T-shaped cross-sectional profile. In an alternative embodiment, projections  12  are aligned at an angle with respect to a centerline (not shown) of stiffener  10 . In a further alternative embodiment, projections  12  are arranged in a helical configuration. 
     In use, stiffener  10  is coupled to an apparatus (not shown in FIG. 1) to facilitate increasing a stiffness-to-mass ratio of the apparatus. Furthermore, stiffener  10  facilitates increasing a natural frequency of the apparatus. In one embodiment, stiffener  10  is attached to the apparatus and circumscribes an exterior of the apparatus. In a further embodiment, stiffener  10  is attached to the apparatus and circumscribes an interior cavity defined within the apparatus. 
     FIG. 2 is an alternative perspective view of stiffener  10  coupled to an apparatus  34 . In the exemplary embodiment, apparatus  34  is substantially tubular and defines a continuous exterior surface  36  to which stiffener  10  is attached. Exterior surface  36  defines a substantially circular cross-sectional profile for apparatus  34 . Alternatively, exterior surface  36  defines a non-circular cross-sectional profile. For example exterior surface  36  defines, but is not limited to defining, at least one of a triangular, an I-shaped, and a T-shaped cross-sectional profile. 
     In the exemplary embodiment, stiffener  10  is coupled to apparatus  34  such that projections  12  circumscribe apparatus  34 , and projections  12  extend radially outward from apparatus  34 . Stiffener  10  is secured to apparatus  34  using a fastener means (Not shown in FIG.  2 ). In one embodiment, the fastener means is an adhesive fastener such as, but is not limited to, a metal glue or a plastic glue. In another embodiment, the fastener means is an adhesive, such as, but not limited to, a double-sided tape, a masking tape, a electrical tape, or a duct tape. In a further embodiment, the fastener means is a mechanical fastener, such as, but not limited to, a nut and bolt, screws, rivets, staples, or clamps. 
     In use, stiffener  10  is coupled to apparatus  34 , and facilitates increasing a stiffness-to-mass ratio of apparatus  34 . During operation, stiffener  10  increases a diameter  38  of apparatus  34 , and provides a local increase in stiffness and a corresponding increase in the natural frequency as apparatus  34  deflects. 
     FIG. 3 is a perspective view of an alternative embodiment of a stiffener  100  coupled to apparatus  34 . Stiffener  100  is substantially similar to stiffener  10 , shown in FIGS. 1 and 2, and components in stiffener  100  that are identical to components of stiffener  10  are identified in FIG. 3 using the same reference numerals used in FIGS. 1 and 2. Accordingly, stiffener  100  includes projections  12  and an outer cover  102 . 
     Outer cover  102  extends across stiffener  100  and has a thickness  104  that is measured between a bottom surface  106  and a top surface  108 . Thickness  104  is variably selected depending on an intended use of stiffener  100  and to ensure stiffener  100  has a pre-determined flexibility for the intended use. Outer cover  102  has a length  22  and a width  24  (Shown in FIG.  1 ), both of which are variably selected depending on an intended use of outer cover  102 . In one embodiment, outer cover  102  is formed from a single sheet of metallic material. In a further embodiment, outer cover  102  is formed from a non-metallic material. Alternatively, outer cover  102  is formed from a plurality of sheets connected together. 
     Projections  12  extend substantially perpendicularly from stiffener bottom surface  16 . More specifically, projections  12  are arranged in a cyclic pattern and extend lengthwise and widthwise across stiffener  100 . Adjacent projections  12  are substantially parallel to each other, and each projection  12  includes a bottom surface  114 , a top surface  116 , and a pair of sidewalls  118  and  120 . In the exemplary embodiment, projection  12  top surface  116  and sidewalls  118  and  120  define a substantially T-shaped cross-sectional profile. Alternatively, each projection  12  defines a non-T-shaped cross-sectional profile. For example, such cross-sectional profiles include, but are not limited to, I-shaped, L-shaped, and V-shaped cross-sectional profiles. 
     In the exemplary embodiment, outer cover  102  is attached to stiffener  100  by a fastener means  122 . Fastener means  122  extends through a portion  124  of outer cover  102 . In one embodiment, fastener means  122  is an adhesive fastener, such as, but not limited to, a metal glue or a plastic glue. In another embodiment, fastener means  122  is an adhesive fastener, such as, but not limited to, double-sided tape, masking tape, electrical tape, or duct tape. In a further embodiment, fastener means  122  is a mechanical fastener, such as, but not limited to, nut and bolt, screws, rivets, staples, and clamps. 
     In use, outer cover  102  is attached to stiffener  100  and stiffener  100  is attached to apparatus  34 , to facilitate increasing a stiffness-to-mass ratio of apparatus  34 . During operation, stiffener  100  increases a diameter  126  of apparatus  34 , and provides a local increase in stiffness and a corresponding increase in the natural frequency as apparatus  34  deflects. In one embodiment, stiffener  100  is attached to apparatus  34  to circumscribe an exterior of apparatus  34 . In a further embodiment, stiffener  100  is attached to apparatus  34  to circumscribe an interior cavity defined within apparatus  34 . Outer cover  102  facilitates an increase in strength, and a reduction in installation time of stiffener  100 . 
     While the invention has been described in terms of various specific embodiments, those skilled in the art will recognize that the invention can be practiced with modification within the spirit and scope of the claims.