Abstract:
A rivet device for securing compressible media is provided herein. The device comprises a rivet with head and shaft portions and a receiving unit. The rivet and the receiving unit are adapted for cooperative reversible rotational engagement. The rivet shaft is inserted into and passes through an aperture in one or more media and engages with the receiving unit on a surface of the media opposite the rivet head portion. Relative rotation in either direction between the rivet and the receiving unit directs reversible engagement of the rivet device. When the rivet device is engaged, the rivet head portion and the receiving unit cooperatively resist tension from the secured media. The rivet shaft is constructed to prevent buckling under pressure or bending under shear from the secured media. A costume assembly kit employing the rivet device to fasten substantially planar costume panels to produce a three-dimensional costume is also provided.

Description:
TECHNICAL FIELD 
       [0001]    The present disclosure relates to rivets for securing compressible media. More specifically, the invention relates to a rivet device for securing wearable panels. 
       BACKGROUND 
       [0002]    Rivets are used to fasten and secure media in a variety of contexts. For example, the use of permanently deformable steel rivets in the construction of buildings and other infrastructure is well known. The rivet features a head on one end of a shaft and a so-called “bucktail” on the distal end. In a basic application, a traditional rivet was hammered in a punched or drilled hole in a medium. The bucktail end was then upset (i.e., deformed), so that it expanded beyond the original shaft diameter to hold the rivet in place. The permanent expansion of the bucktail end allowed the rivet to support tension loads (loads parallel to the axis of the shaft), as well as shear loads (loads perpendicular to the axis of the shaft) without need for replacement. However, such rivets provide imperfect solutions where a removable, reusable fastener is required. 
         [0003]    For example, many holiday and special event decorations requiring a fastener, such as honeycomb paper constructions, are only occasionally assembled and are otherwise disassembled or compressed for efficient storage to be re-used at a later date. Permanent fasteners such as traditional rivet designs do not permit reversible media fastening and cannot be re-used due to deformation. Alternative fasteners such as paperclips, brass fasteners and the like may be used in such instances, however, they suffer from high failure rates and other issues. 
         [0004]    Rivets manufactured from deformable plastics are also known, but are not designed for repeated re-use. A truly reusable rivet could have utility in a variety of environments, beyond those contemplated in the prior art. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0005]      FIG. 1  is an isometric view of an example embodiment of a removable rivet device in accordance with the invention depicted in the assembled but unlocked state. 
           [0006]      FIG. 2  is an isometric view of the rivet portion of an example embodiment of the rivet device. 
           [0007]      FIG. 3  is an isometric view of a washer portion of an example embodiment. 
           [0008]      FIG. 4  is a sectional view taken along line  4 - 4  of  FIG. 1  of an example embodiment depicted in the assembled and locked state. 
           [0009]      FIG. 5  is an isometric, environmental view of an example embodiment depicted in an uninstalled, unassembled and unlocked state. 
           [0010]      FIG. 6  is a side elevational environmental view of an example embodiment depicted in an installed, assembled and locked state. 
           [0011]      FIG. 7  shows an assembled state left-side perspective view of a role playing costume kit utilizing the rivet device of example embodiments. 
           [0012]      FIG. 8  shows a top view of unassembled planar state components of the costume kit of  FIG. 7 . 
       
    
    
     DETAILED DESCRIPTION 
       [0013]    Inexpensive, reusable fastening devices that are easily manipulated, are not permanently deformed in use, and which yet enjoy the strength and reliability of a traditional rivet have a wide variety of uses, including for example, to assemble wearable panels such as in a garment to be worn as a costume. A bowtie tang rivet device in accordance with these principles is generally indicated at reference numeral  10  in the various figures of the attached drawings wherein numbered elements in the figures correspond to like numbered elements herein. 
         [0014]    As seen in  FIGS. 1 and 4 , the rivet device  10  includes a rivet  20  having a non-permanently-deforming bucktail or shank  26  connected to a head  22 . The shank  26  terminates in a bow-tie tip  24 . The head  22  is sufficient in diameter to allow manual installation through media with little force by pushing on the head to drive the bowtie tip  24  and shank  26  through installation media  100  and  104 , such as compressible layers of a garment as shown in  FIGS. 5 and 6 . The head has a diameter  28  sufficient to anchor the shank  26  against the compressible installation media  100  and  104 , permitting tension loading at the bowtie tip  24  while not inducing tearout failure of the installation media  100  and  104 . As will be described in greater detail below, the bowtie tip  24  is adapted for releasable engagement with a receiving unit or twist-to-lock washer  50 . As seen in  FIGS. 2 and 4 , the rivet shank  26  is typically cylindrical in longitudinal cross-section and is typically absent rings or notches. The shank  26  is of sufficient diameter  30  to prevent buckling under compression and bending under shear. The shank has a height  32  set appropriately with a shoulder  34  between the shank  26  and bowtie tip  24  such that the media  100  and  104  will compress when the rivet is engaged with the washer  50 . The span between a rivet head flat  36  and shoulder  34  constitutes the rivet&#39;s intended installation thickness. When the rivet device  10  is in a locked position, as will be described further below, relaxation of the secured compressible installation media  100  and/or  104  urges the washer  50  axially away from the shank shoulder  38 , thus further locking the rivet device  10 . The shoulder  34  contains a radius  38  to prevent snagging during installation. The shank  26  has a reduced diameter  40  at the shoulder  34  sufficient to permit tension loading where compression and shear are not present. Further along the shank  26 , opposite the head portion  22  and consistent with the radius  38  of the shoulder  34 , the bowtie tip  24  is rounded over on its distal end and has radii  42  on all leading edges to permit snag-free passage through installation media  100  and  104 . The bowtie tip  24  and shank  26  are plunged through two or more planar items  100  and  104  by pressing on the rivet head  22 . The shank surface  30  is smooth to facilitate smooth travel through the installation mediums  100  and  104  with little force on the rivet head  22 . The shank  26  will not buckle from the compression of column loading and the shank  26  will not bend from the shear caused by planar slip of the installation mediums  100  and  104 . Unlike the shank  26 , the bowtie tip  24  deviates at the shoulder  34  from a cylindrical shape to a bowtie shape. The bowtie shape is incorporated in the bowtie tip  24  and cooperatively matched in the twist-to-lock washer  50  as will be described further below. In example embodiments, the rivet device  10  is manufactured from nylon or another suitable polymer material in a conventional fashion. 
         [0015]    As illustrated in  FIGS. 3 and 4 , the washer  50  has four inwardly radially directed obstructions  56  located in the inner diameter of the washer  50  which project from the inner diameter  58 , forming the bowtie shape of a bow-tie-shaped hole  52  on a bottom  54  of the washer  50 . Adjacent obstructions  56  form a pair which define a relief or detent  60 . That is, a relief  60  is defined by each pair of obstructions  56  and is sized sufficiently to receive rivet tangs  44  located on the bow-tie tip  42  of the shank  26 . The bowtie tip  24  is aligned with the complementary bowtie hole  52  in the washer bottom  54 , and the washer  50  is pressed on to the tip  24 . The washer  50  is then turned 90 degrees to lock the washer with respect to the rivet. Twisting the washer  50  requires little force, and the moment induced on the bowtie tip  24  and shank  26  by the locking action is carried by the shank  26 , head flat  36 , and friction on the installation mediums  100  and  104 . The installed and locked fastener  106  is in equilibrium from rivet head  22  to lock washer  50 . Tension on the lock washer  50  is resisted by the rivet head  22 . Tension on the rivet head  22  is resisted by the locked washer  50 . Planar slip of the installation mediums  100  and  104  imparts a shear load on the shank  26  which the shank is sufficient to resist. Compression of the installation mediums  100  and  104  is largely present during installation of the rivet device  10  and thereafter. 
         [0016]    The locking function of the fastener is generated by two components; one contained in the rivet  20  and one contained in the washer  50 . The rivet tip  24  contains two diametrically opposed symmetric interference tangs  44  that are housed on a back side of the bowtie tip  24  between the shank shoulder  34  and bowtie tip  24 . The tangs  44  are protected from contact with the installation media  100  and  104  by the bowtie tip  24  and possess radii and chamfers sufficient to prevent snagging with installation media  100  and  104  during removal of the rivet  20 . The tangs  44  temporarily axially deflect when the washer  50  is moved to the locked or unlocked position, returning thereafter to a rest position. The tangs are sufficient in size and span to cause interference with the washer  50  and require an adequate amount of torque allowing for hand installation while resisting vibration or loosening action. By way of example, a rivet device  10  having a shank diameter of 0.180″ and an overall height of 0.545″ may have a tang height of 0.020″. 
         [0017]    As stated above, the washer  50  provides a pair of detents with the rivet tangs  44  by way of two pair of obstructions  56  located on the inner diameter  58  of the washer  50 . The bottom  54  of the washer  50  is placed over the bowtie tip  24  of the rivet  20 . The washer head  62  is recessed at a depth and diameter sufficient to permit counter rotation between the washer  50  and the bowtie tip  24 . Relative bidirectionalrotation of the rivet  20  with respect to the washer  50  or of the washer  50  with respect to the rivet  20  engages the rivet tangs  44  with the washer obstructions  56 . The tangs  44  are tapered sufficiently to permit a ramping effect, and interference between the two parts causes axial elastic deformation of the rivet tangs  44  and bowtie tip  24 . The tang tips  46  contain radii to permit a smooth ramping transition from the relaxed state to the deformed state. Deformation of the washer obstructions  56  is prohibited by the shoulder  34  on the rivet shank  26 . A sufficient amount of torque is required to drive the rivet tang tips  46  past the obstructions  56  until the tangs  44  reach proximity to the obstruction reliefs  60 . Upon coincidence of the tangs  44  and reliefs  60 , the tangs  44  and bowtie tip  24  relax elastically, and the rivet device  10  is locked. As seen in  FIG. 4 , a gap (un-numbered) exists between an axial surface of the tangs  44  and obstructions  56 . This gap is narrowed or eliminated by relaxation of the elastic installation media  100  and  104 , which urges the washer  50  away from the shoulder  38  so that the top surfaces of obstructions  56  are in contact with the tip bottom  24 . Expansion of the installation media  100  and  104  thus provides additional locking between the rivet  20  and the washer  50  and creates additional engagement depth between the tangs and reliefs. 
         [0018]    Installation and locking of this rivet device  10  causes little wear to the interference components  44  and  56 . The washer  50  can be repeatedly removed from the bowtie tip  24  with the same procedure for installation. Due to the symmetric design of the bowtie tip  24 , rotation between the rivet  20  and washer  50  can be bi-directional. Installation and removal can be repeatedly achieved with a 90 degree turn in either the clockwise or counterclockwise direction. Upon removal of the washer  50 , the rivet  20  can be removed from the installation mediums  100  and  104  by pulling on the rivet head  22  at the rivet head diameter  28 . The design of the rivet shank  26 , shoulder  34 , bowtie tip  24  and tangs  44  are such that the rivet  20  will remove with ease, free from snagging or catching the installation mediums  100  and  104 . The removed rivet device  10  does not suffer permanent deformation or yield and is suitable for reuse multiple times. 
         [0019]    The rivet device  10  and washer  50  have utility in a variety of settings. In fashion and costume design, for example, creatively-designed garments require reliable, reusable and reversible fastening means. In recent times, intricate costumes designs inspired by film, animation and computer games have grown in popularity. The ideal costume is true to the underlying concept, aesthetically pleasing, and comfortable for the wearer. Such costume designs require more sophisticated construction and functionality than can be offered by traditional rivets, and yet may require the strength and stability of a rivet over other fasteners. Traditional fasteners may cause discomfort to the wearer and inhibit mobility, thereby negating any advantages gained by the fastening. One example is shown in  FIG. 8  where a child&#39;s costume component (e.g., a helmet)  100  comprises various panels  110 - 122  of planar foam or other suitable elastically deformable material having a design thereon. Assembly of the panels is accomplished with a plurality of the rivet devices  10  and washer  50  (hidden from view) of those described here, and permits the costume to assume a three-dimensional shape as shown in  FIG. 7 . Other types of garments including those to be worn for purposes other than costumes are also contemplated. 
         [0020]    From the foregoing it will be appreciated that, although specific examples have been described herein for purposes of illustration, various modifications may be made without deviating from the spirit and scope of the invention. For example, the rivet shank  26  may be square in cross-section rather than cylindrical to prevent counter-rotation of the secured media  100  and  104 . Thus, the invention is not to be limited to the above description, but is to be determined in scope by the claims which follow.