Abstract:
An anchor for a screw fastener for hollow walls and doors and solid walls and doors, the anchor of two-piece construction having a nose piece with conical end portion and a cooperative lock nut which is drawn over the conical end portion of the nose piece upon influence of rotation of the screw causing the lock nut fingers to flare out and engage the interior surface of a hollow wall or the circumferential surface of a bore in a solid wall.

Description:
RELATED APPLICATIONS 
       [0001]    Applicant claims the benefit of provisional application 60/959,782, filed Jul. 18, 2007. 
     
    
     BACKGROUND OF THE INVENTION 
       [0002]    1. Field of the Invention 
         [0003]    The present invention relates to anchors used in supporting articles on walls or doors, and in particular, the present invention relates to anchors for use on hollow walls and doors yet has application to solid walls and doors. 
         [0004]    2. Description of the Prior Art 
         [0005]    Hollow walls, which comprise most interior walls of building are generally comprised of a gypsum board, plaster board, drywall, or the like of a thickness generally of ½ to ⅝ths of an inch. This wall board is normally mounted on parallel, vertically oriented studs, thus forming a hollow or cavity defined by two adjacent studs and the wall board sheathing. 
         [0006]    A similar situation rises in interior doors, which are often time framed out and covered by a thin wooden veneer on both sides, which again creates hollows or cavities in the door defined as a space between the framing and the opposing veneer sheathing. 
         [0007]    The gypsum board, plaster board, door sheathing, drywall or plaster are of limited structural integrity and in the case of gypsum board, dry wall or plaster board owe much of its strength to the paper used to enclose the compressed powder. They will not adequately support items hung thereon with simple nails, or even standard screws, unless the fasteners in the form of nails or screws pass through the gypsum board, drywall, plaster board or the like and are anchored in one of the interior studs. Since these studs are spaced apart per construction codes, an interior wall has significantly greater hollow space than it does solid space (i.e. drywall stud drywall). 
         [0008]    As a result of this excess hollow space, the homeowner oftentimes finds himself having to anchor a fastener in an interior wall in a location in which the fastener only penetrates the gypsum board, plaster board or drywall or the like. This need could be for hanging a decorative item, such as a painting or mirror, or for hanging utility items, such as shelving. 
         [0009]    There are a myriad of hollow wall anchors which have been developed and are used in conjunction with a nail or screw for enhancing holding strength in these situations. Common anchors of this type often have drawbacks. Plug anchors made of metal, plastic or fiber which are expanded by an inserted screw against the interior gypsum of the wall board still rely on the tenuous holding strength provided by compressed powder gypsum. Other anchors include toggle bolts, which cannot be reused and which require pre-drilled holes for installation. Self-installing drive-in molly bolt anchors may damage a wall if not properly installed. Many of the hollow wall anchors are susceptible to loosening and failure, particularly with a dynamic load, such as the removal and replacement of pictures or paintings or other typical wall vibrations. 
         [0010]    Still further, many anchors exert a spreading force on their apertures, which is not always reliable and secure, and can cause the fastener to fail over time under heavier weight loads. Self-drilling anchors leave a large hole in the drywall, and are not useful for thin panels such as sheathing veneer on hollow doors, or on plaster. Metal toggle bolts require a large hole and are not normally useful in hollow doors or plaster. Molly bolts are not useful for hollow doors or plasters, and are difficult to remove, leaving a large hole in the drywall. 
         [0011]    Each of the aforesaid prior art anchors are also susceptible to be easily over-tightened such that they distort the drywall, gypsum board or plaster board, which affects the aperture through which they are inserted, and thus may weaken their intended purpose. 
         [0012]    Applicant&#39;s novel contribution to the art addresses the shortcomings of the prior art fasteners and introduces a unique two-piece design anchor requiring a small aperture in which does not distort the surface and eliminates the possibility of over-tightening, and in many instances, presents an anchor which can be reused. Applicant&#39;s anchor also has application not only to hollow walls and doors, but also solid walls and doors. 
       OBJECTS OF THE INVENTION 
       [0013]    An object of the present invention is to provide for a novel hollow wall anchor of two-piece design which does not distort the surface through which it is inserted, and which eliminates the possibility of over-tightening so as to deform or distort the anchoring material. 
         [0014]    A still further object of the present invention is to provide for a unique hollow wall fastener of two-piece construction wherein the two pieces are interchangeable such that the fastener can accommodate wall material of different thicknesses. 
         [0015]    A still further object of the present invention is to provide for a novel hollow wall fastener which can be reused. 
         [0016]    A still further object of the present invention is to provide for a novel fastener anchor for solid walls and doors. 
       SUMMARY OF THE INVENTION 
       [0017]    An anchor for a screw fastener for hollow walls and doors and solid walls and doors, the anchor of two-piece construction having a nose piece with conical end portion and a cooperative lock nut which is drawn over the conical end portion of the nose piece upon influence of rotation of the screw causing the lock nut fingers to flare out and engage the interior surface of a hollow wall or the circumferential surface of a bore in a solid wall. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0018]    These and other objects of the present invention will become apparent, particularly when taken in light of the following illustrations wherein: 
           [0019]      FIG. 1  is an exploded side view of the anchor of the present invention; 
           [0020]      FIG. 2  is a side view of the anchor of the present invention in the course of being installed to a hollow wall; 
           [0021]      FIG. 3  is a side view of the anchor of the present invention in a fully fixed, secure, installed position in a hollow wall; 
           [0022]      FIG. 4  is a side view of the anchor of the present invention utilized to secure an object to a solid wall; and 
           [0023]      FIG. 5  is a partial end view of a portion of the anchor assembly. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0024]      FIG. 1  is an exploded view of the anchor  10  of the present invention,  FIG. 2  is a side view of the anchor  10  of the present invention in the course of being installed to a hollow wall,  FIG. 3  is a side view of the anchor  10  of the present invention fully installed in a hollow wall, and  FIG. 5  is a partial end view of a finger of the lock nut assembly. 
         [0025]    Anchor  10  is of two piece construction having a nose piece  12  and a cooperative lock nut  14 . Nose piece  12  comprises a barrel member  16  of generally cylindrical construction having a truncated conical end portion  18  and a flange end  20 . Centrally disposed through both the flange end  20 , barrel member  16  and truncated conical end portion  18 , is a throughbore  22 . 
         [0026]    Formed about the circumference of barrel member  16  are a plurality of axial upstanding ridges  24  in parallel relationship with throughbore  22 . Formed on truncated conical end portion  18  are a plurality of slots or voids  26  which radiate from truncated conical end  23  towards barrel member  16 . 
         [0027]    Lock nut  14  is tubular in shape having a threaded throughbore  23 . First end  32  of lock nut  14  is formed with a plurality of fingers  34 , the number of fingers  34  being equal to the number of slots or voids  26  formed on truncated conical end portion  18  of nose piece  12 . Fingers  34  have a concave profile in order to cooperate with truncated conical end portion  18  of nose piece  12  (See  FIG. 5 ). Formed on the inner surface  36  of fingers  34  are upstanding ridges  38 . Upstanding ridges  38  are slidably receivable within slots or voids  26  on nose piece  12  as hereinafter described. In the preferred embodiment, the leading edge of upstanding ridges  38  would be beveled or rounded for ease of engagement with slots or voids  26 . 
         [0028]    Referring to  FIGS. 2 and 3  and the installation of anchor  10 , the appropriate location on the wall  50  would be identified for the installation of the anchor. A suitable aperture would be drilled into wall  50 . The diameter of the aperture would approximate the diameter of the barrel member  16  of nose piece  12  absent axial upstanding ridges  24 . This aperture would normally be in the range of from quarter to five sixteenths of an inch. The hook  52  or other piece of hardware to be positioned on the wall would be juxtaposed flange end  20  of nose piece  12 . A threaded fastener  54 , in the form of the screw, would then be inserted through the aperture  56  in the hardware, through throughbore  22  of nose piece  12  and into threaded inner tubular throughbore  22  of lock nut  14 . Threaded fastener  54  would then be rotated, engaging the threaded inner tubular throughbore  22  of locknut  14  so as to draw locknut  14  towards nose piece  12  such that the upstanding ridges  38  on fingers  34  of locknut  14  engage with slots or voids  26  on truncated conical end portion  18  of nose piece  12 . 
         [0029]    With the nose piece  12  and lock nut  14  assembly thus completed, the lock nut  14  and nose piece  12  are inserted into the aperture formed in wall  50  until flange end  20  of nose piece  12  is juxtaposed the outer surface  51  of wall  50 . The hook or alternative hardware  52  is now similarly juxtaposed the outer surface  51  of wall  50 . 
         [0030]    The threaded fastener  54  would then be further rotated so as to draw lock nut  14  towards barrel member  16  of nose piece  12 , which due to the cooperation between truncated conical end portion  18  and fingers  34  on lock nut  14 , causes the fingers  34  to bend or extend outwardly until as illustrated in  FIG. 3 , the end tips of fingers  34  are juxtaposed the inner surface  53  of wall  50 . The bend or outward extension of fingers  34  is facilitated by annular grooves  32  formed in fingers  34 . 
         [0031]    In the process just described, the axial ridges  24  on barrel member  16  of nose piece  12  prevent the rotation of nose piece  12  by engaging the wall  50  about the periphery of the drilled aperture. 
         [0032]    The upstanding ridges  38  on fingers  34  cooperate with the slots or voids  26  on truncated conical end portion  18  of nose piece  12  to prevent locking nut  14  from freely rotating. Therefore, under the influence of the threaded fastener  54 , locking nut  14  must move axially towards nose piece  12 , thus causing fingers  34  to bend or spread outwardly so as to engage the inner surface  53  of wall  50 . 
         [0033]      FIG. 4  is a side view of anchor  10  being utilized with respect to a solid wall. The structure of anchor  10  remains the same. An appropriate aperture is drilled into the solid wall  60 . Anchor  10  and the hardware  52  that it is to secure is then inserted into the aperture until flange end  20  is juxtaposed the outer surface  61  of the solid wall  60 . The threaded fastener  54  is then rotated which causes fingers  34  on lock nut  14  to spread such that they frictionally engage the inner surface  63  of the bore  64  which was drilled resulting in a firm fastening of all components. 
         [0034]    Therefore, while the present invention has been disclosed with respect to the preferred embodiments thereof, it will be recognized by those of ordinary skill in the art that various changes and modifications can be made without departing from the spirit and scope of the invention. It is therefore manifestly intended that the invention be limited only by the claims and the equivalence thereof.