Abstract:
A nut and bolt cover apparatus is preferably made from three pieces. A cover piece may be placed over a nut and may have an adapter piece placed over the cover. An exterior cover may be releasably attached to the adapter piece and may squeeze a portion of the adapter piece as the exterior cover is releasably attached to the adapter. Squeezing the adapter piece preferably compresses the cover piece and causes the cover piece to grip the nut of a nut and bolt assembly while the adapter piece grips the cover piece. Removing the exterior cover may relieve the compression forces causing the adapter piece to grip the cover piece and the cover piece to grip a nut, thus permitting the nut and bolt cover apparatus to be removed.

Description:
RELATED APPLICATION DATA 
     This application claims priority under 35 U.S.C. §119(e) to U.S. Provisional Application No. 61/141,525 titled “Nut and Bold Cover” filed on Dec. 30, 2008, which is fully incorporated by reference herein. 
    
    
     BACKGROUND 
     The field of the present disclosure relates to a system or apparatus for covering a nut and bolt assembly. Covers for nut and bolt assemblies are used for a variety of reasons, including protecting nut and bolt assemblies from environmental hazards, preventing tampering with a nut and bolt assembly, and for aesthetic purposes. 
     A variety of approaches have been taken for securing an apparatus for covering a nut and bolt assembly to the nut and bolt assembly. For example, covering apparatuses have been designed to be incorporated into a lug nut as in U.S. Pat. Nos. 2,018,301 and 4,775,272, to be secured to a bolt protruding past a nut as in U.S. Pat. Nos. 2,095,289, 3,548,704, and 4,824,305, to have a deformable portion that deforms to hold the cover on a nut as in U.S. Pat. No. 4,582,462 and U.S. Pat. No. 4,784,555, and to be secured using adhesives as in U.S. Pat. No. 4,764,070, among other techniques for securing a cover to a nut. 
     The present inventors have recognized limitations and drawbacks associated with existing apparatuses for covering nut and bolt assemblies. For example, some present apparatuses are not able to remain secured to a nut and bolt assembly after being removed and reinstalled because of wear or loosening parts. Other apparatuses rely on a portion of a bolt or stud to protrude past a nut, which does not always occur. Still other apparatuses require tools or adhesives for installation. The present inventors have also recognized various needs for an apparatus for covering nut and bolt assemblies that does not require tools to install, or that may be uninstalled and reinstalled without losing its ability to stay in place on a nut, or that does not rely on an exposed bolt or stud for securement, singularly or in any combination. 
     SUMMARY 
     Embodiments of the present invention may address some or all of the above identified limitations and/or needs, or may address other suitable needs. An exemplary apparatus/system or method for covering a nut and bolt assembly includes a nut cover, an adapter including a structure for releasably attaching an exterior cover to the adapter, and an exterior cover including a reciprocal structure for releasably attaching to the adapter. The exterior cover is preferably designed to apply a compressive force to the nut cover via the adapter when the exterior cover is releasably attached to the adapter. 
     In a preferred embodiment, installing a nut cover on a nut and bolt assembly involves placing a nut cover, or gripping element, over the nut. An adapter, or force transfer piece, is preferably placed over the cover. An exterior cover, or compression force applying piece, is releasably secured to the adapter. When the exterior cover is releasably secured to the adapter, the exterior cover preferably slides over the adapter to create a compression force on the adapter proximate where the adapter contacts the cover. Preferably, the adapter deforms in a direction substantially orthogonal to the surface of the cover when the exterior cover is installed, thus creating a compression force on the cover with little or no shear forces. In other words, the adapter preferably does not slide with respect to the cover. 
     Additional aspects and advantages will be apparent from the following detailed description of preferred embodiments, which proceeds with reference to the accompanying drawings. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is an assembly view of a preferred embodiment. 
         FIG. 2  is a cut away view of the embodiment of  FIG. 1  with the components assembled. 
         FIG. 3  is a cut away view of the adapter of  FIG. 1 . 
         FIG. 4  is a cut away view of the exterior cover of  FIG. 1 . 
         FIG. 5  is a top front isometric view of an adapter for another embodiment. 
         FIG. 6  is a bottom isometric view of the adapter of  FIG. 5  illustrating the adapter and a cover placed over a nut, but with the nut removed for clarity. 
         FIG. 7  is a cut away view of the adapter and cover of  FIG. 6  placed over a nut and with an exterior cover releasably attached to the adapter, but with the nut removed for clarity. 
     
    
    
     DETAILED DESCRIPTION OF PREFERRED EMBODIMENTS 
     Preferred embodiments will now be described with reference to the drawings. While several preferred embodiments are described with reference to a nut and bolt assembly cover used with lug nuts, a practitioner in the art will realize from the description that the principles described are viable to other applications. The described embodiments, as well as other embodiments, have numerous applications where a nut and bolt assembly is covered for protection from an environment likely to damage, discolor, or disfigure the nut and bolt assembly, is covered for aesthetic purposes, or is covered for other suitable reasons. Embodiments may be scaled and adapted to many applications. 
       FIGS. 1 and 2  illustrate an exemplary nut and bolt including a lug nut  100  used to secure a wheel  200  to a wheel hub (not illustrated for clarity) via threaded wheel studs  105 .  FIG. 1  is an exploded view of a nut and bolt cover assembly  5  that includes several components, preferably, a nut cover  35 , an adapter  25 , and an exterior cover  10 . In preferred embodiments, the nut cover  35  is placed over the lug nut  100 , followed by the adapter  25  and then the exterior cover  10 . The exterior cover  10  may secure a decorative hub cap (not illustrated) in place on the wheel hub. 
     As described in more detail below, attaching the exterior cover  10  to the adapter  25  exerts a compressive force on a nut end  29  of the adapter  25 . The compressive force on the nut end  29  of the adapter  25  preferably exerts a compressive force on the nut cover  35  via the nut end  29  as also described below. By compressing the nut end  29  and the nut cover  35 , the nut and bolt cover assembly  5  grips the lug nut  100  to remain securely in place. 
       FIGS. 1-4  illustrate the cover assembly  5  for attaching to a lug nut  100  and wheel stud  105  assembly. Wheel  200  is retained to the wheel hub (not illustrated for clarity) using wheel stud  105  and lug nut  100  as commonly known. A nut cover  35  is placed over the lug nut  100 , preferably by slipping the nut cover  35  over the lug nut  100 . The nut cover  35  may be pre-shaped to accommodate the lug nut  100 , as illustrated in  FIG. 1 , or may be deformable to readily conform to the contour of the lug nut  100 , for example, by using a rubber or soft plastic sleeve. A pre-shaped nut cover  35  may include a ring  37  with tabs  39  projecting from one side. Preferably, a pre-shaped nut cover  35  includes a plurality of extensions, tabs, flares, fingers, or other suitable structure for gripping a nut, where the number of extensions or the like correspond to the number of sides of the nut. For example, a nut cover  35  with six tabs  39  may be used with a hexagonal nut. The tabs  39  may be configured to correspond to the outer surfaces of the nut  100 , and may include a nut gripping inside surface  38  and an adapter engaging outer surface  36 . 
     The adapter  25  is slipped over the nut cover  35  so that a nut end  29  contacts the nut cover  35 . The adapter  25  is preferably shaped in what may be described as a flowerpot as illustrated in  FIGS. 1 and 3 , but may have any suitable shape, including, but not limited to, a cylindrical shape, a conical shape, or frustoconical shape. The nut end  29  preferably includes an elastically deformable section, for example, a section including adapter tabs  55  separated by slots  65 . A substantially cylindrical sidewall  40  extends between the exterior cover end  27  and the nut end  29 . 
     The exterior cover end  27  of the adapter  25  preferably includes an attachment structure for releasably attaching an exterior cover  10  to the adapter  25 . For example, a threaded bolt  20  may be held in an aperture  45 ,  50  ( FIG. 3 ) by a nut  15 . In the assembly  5 , the bolt  20  is inserted from the inside of the adapter  25  and through the hole  45 ,  50  ( FIG. 3 ) and then secured in position extending outwards from the closed end of the adapter  25 . The bolt  20  may be secured in place by ring nut  15  or a clip or other suitable mechanism, by press fitting the bolt  20  or bold head  21  into the aperture  45  and/or  50 , by using a threaded aperture, by using an adhesive, or by welding. 
     The exterior cover  10  has a generally thimble-shaped structure with open base end  14  and closed tip end  12 . The exterior cover is releasably attached to the adapter  25 . For example, the tip end  12  of the exterior cover  10  may carry a female threaded receiver  11  ( FIG. 4 ) that threadably engages the bolt  20 . A rotational force is imparted to the exterior cover  10  to engage the threaded receiver  11  with the bolt  20 . As the exterior cover  10  is releasably attached to the adapter  25 , the base end  14  of the exterior cover  10  rotates and moves linearly towards the nut  100  to engage the nut end  29  of the adapter  25  and impart a compressive force. Preferably, the compressive force is created by pressing the elastically deformable section of the nut end  29  towards the nut  100  as the interior surface  13  ( FIG. 4 ) of the exterior cover  10  slides over the nut end  29  of the adapter  25 . 
     The compressive force created by sliding the exterior cover  10  over the adapter  25  acts on the nut cover  35  via the nut end  29 . Once installed/assembled, there is preferably no sliding between the surfaces of the nut  100  and the nut cover  35 , and no sliding between the surfaces of the nut cover  35  and the adapter  25 . For example, there may be a relatively high static coefficient of friction between the lug nut  100  and the nut cover  35  as well as a relatively high static coefficient of friction between the nut cover  35  and the nut end  29  as the exterior cover  10  engages the adapter  25 . 
     Additionally, the exterior surface of the adapter  25  and the interior surface of the exterior cover  10  that contact each other preferably slide relatively easily over each other. For example, the static coefficient of friction between the exterior cover engaging surfaces  54  on the adapter tabs  55  at the nut end  29  of the adapter  25  and the interior surface  13  proximate the base end  14  of the exterior cover  10  is preferably lower than the static coefficient of friction between the lug nut  100  and the nut cover  35  and also lower than the static coefficient of friction between the nut cover  35  and the nut end  29  of the adapter  25 . The combined effect of the various static coefficients of friction preferably permits the base end  14  of the exterior cover  10  to slide over the nut end  29  of the adapter  25  without imparting a rotational motion to the adapter  25 . Squeezing, but not rotating the adapter  25 , may thus provide a compressive force on the nut cover  35  with little or no shear forces acting on the nut cover  35 . 
     By reducing or eliminating shear forces from acting on the nut cover  35 , the likelihood that the nut cover will move, or slip, with respect to the lug nut  100  is decreased. Thus, the likelihood of loosening, or causing wear on, the nut gripping surfaces  38  of the nut cover  35  ( FIG. 1 ) or the nut cover gripping surfaces  56  of the adapter  25  ( FIG. 3 ) is reduced which may increase the number of cycles the nut and bolt cover  5  may be removed and replaced without becoming loose. 
     Once installed, the exterior cover  10  preferably substantially covers the lug nut  100 . For example, the exterior cover may contact a surface held in place by the nut and bolt assembly, extend past the bottom of a nut, or may stop short of the bottom of a nut. Extending the exterior cover  10  to contact a surface held in place by the nut and bolt assembly, or to another position, may create a first barrier to impede debris from reaching the lug nut  100 . The cover  35  over the lug nut  100  may act as a second barrier to impede debris from reaching the lug nut  100 . 
     The exterior cover  10  is preferably secured to the flowerpot-shaped adapter  25  via a threaded interconnection, such as the one described above, or by some other suitable interconnection. Another exemplary threaded connection may be configured without the bolt  20  by providing male threads, for example, in the region proximate where arrow “S” points in  FIG. 3 , along the outer surface of the adapter  25 . Corresponding female threads may be provided on the exterior cover  10 , for example, in the region proximate where arrow “T” points in  FIG. 4 , along the inner surface  13  of the exterior cover  10  proximate the closed end. Other attaching structures may secure the exterior cover  10  to the adapter  25 . For example, a quarter-turn quick connect, a press or interference fit, or other suitable structure may be used. 
     Many materials and surface finishes may be used to alter the sliding relationship between surfaces, for example, by creating different static coefficients of friction between the various surfaces. The static coefficient of friction (μ) is commonly defined as the ratio of the tangential force (F), that is, a force acting in a direction parallel to a surface, required to cause sliding between the two surfaces divided by the force that is acting perpendicular (N) to the two surfaces. In other words, μ=F/N. Therefore, changing the material used, and/or changing the finish for a surface, for example, but not limited to, texturing a surface by creating dimples, ridges, or roughening; polishing a surface; or other suitable alterations, affect the static coefficient of friction between two surfaces. Modifying the static coefficient of friction using different materials and/or finishes may prevent movement between the nut cover  35  and the lug nut  100 , and between the nut cover  35  and the adapter  25 . Likewise, altering materials and/or finishes may modify the static coefficient of friction to facilitate sliding movement between the adapter  25  and the exterior cover  10 . 
     One example that may achieve desirable static coefficients of friction between the various surfaces is to make the nut cover  35  from a technically specified rubber (“TSR”) with a 60 durometer Shore A hardness, to make the adapter  25  from polypropylene, polycarbonate or a combination of polypropylene and polycarbonate, and to make the exterior cover  10  from acrylonitrile butadiene styrene (“ABS”) plastic. Other suitable materials may be used. One advantage of a three piece cover  5  may be that relatively rigid materials are used for the components that releasably attach to create a compression force, while a relatively soft material is used to receive the compression force and grip the nut. 
     Alternatively, portions of the adapter  25  designed to contact the nut cover  35 , such as the nut cover gripping surfaces  56  on adapter tabs  55  ( FIG. 3 ), may include a layer of material such as Santoprene®, natural rubber, or other suitable material to increase the static coefficient of friction between the adapter  25  and the nut cover  35 . Alternatively, a gripping structure, such as raised ribs  60  or grooves  62  ( FIG. 3 ), raised dots (not illustrated), dimples (not illustrated), texturing (not illustrated), or other suitable structure may be included on the nut cover gripping surfaces  56 . Similar modifications may be made to the portions of the nut cover  35  that contact the lug nut  100 . The interior surface  13  ( FIG. 4 ) of the exterior cover  10  may be polished to reduce the static coefficient of friction between the exterior cover  10  and the adapter  25 . Likewise, the exterior of the adapter  25  may be polished. 
     Another manner to control whether two surfaces slip with respect to one another is to modify the isothermal compressibility of the materials. For example, the nut cover  35  may be made from a material with an isothermal compressibility that is greater than the isothermal compressibility of the material for the adapter  25 . And, the adapter  25  may be made from a material with an isothermal compressibility similar to the isothermal compressibility of the material for the exterior cover  10 . By permitting a portion of the adapter  25  to displace into the nut cover  35  (due to the different isothermal compressibility of the materials), resistance to sliding may result from both the static coefficient of friction between the materials and the physical interference caused by the less compressible adapter  25  displacing into the more compressible nut cover  35 . 
     Additionally, the outside of the exterior cover  10  may be electroplated with chrome, or otherwise suitably altered, to provide environmental protection, for aesthetic purposes, or for other purposes. 
     Alternate embodiments may shape components including a nut cover, an adapter, and an exterior cover differently. For example,  FIGS. 5-7  illustrate an embodiment of a nut cover  350  having an elastically deformable sleeve. The nut cover  350  may be made from TSR with a 60 durometer Shore A hardness, other TSR, polychloroprene, or other suitable material. Preferably, the nut cover  350  is readily deformable to accommodate the shape of a nut (nut not illustrated in  FIGS. 6-7  for clear viewing of how the nut cover  350  may deform). 
     The adapter  250  includes a ring  255  on an upper surface. The exterior cover end  260  includes an attaching structure  265  extending from the ring  255 . The attaching structure  265  may include a post  260  sized to create an interference fit with a sidewall  1015  of a recess  1005  in the exterior cover  1000 , or may include a threaded post (not illustrated), a post bearing a snap fit structure (not illustrated) such as a ridge sized to fit into a groove in the sidewall  1015  (or vice versa), or other suitable structure. 
     The adapter nut end  270  includes a number of tabs  275  for engaging the nut cover  350 . The tabs  275  preferably extend from the ring  255  in a direction opposite the attaching structure  265 . Preferably, each tab  275  is arranged at an angle with respect to a tangent to the edge of the ring  255 , for example a  3  degree angle. For example, the end of the tab  275  that is distal from the ring  255  may be farther from a central axis of the ring  255  than the end of the tab  275  that is proximate the ring  255 . Setting the tabs  275  at an angle may facilitate creating a compression force on the nut end  270  of the adapter  250  when the exterior cover  1000  is releasably attached. Other suitable arrangements may be used, such as increasing the thickness of each tab  275  in a direction extending away from the ring  255 , for example, or combining increasingly thick tabs with angularly offsetting the tabs. 
     Each tab  275  preferably includes a nut cover engaging surface  280  and an opposing exterior cover engaging surface  285 . Nut cover engaging surfaces  280  are preferably designed to reduce the likelihood that a nut cover engaging surface  280  will slide with respect to the nut cover  350 . On the other hand, exterior cover engaging surfaces  285  are preferably designed to facilitate sliding between an exterior cover engaging surface  285  and the interior  1010  of the exterior cover  1000 . The interior  1010  of the exterior cover  1000  may also be designed to facilitate such sliding, for example, by polishing. 
     The exterior cover  1000  is illustrated with a recess  1005  sized to create an interference fit with the attaching structure  265 . As previously discussed, other suitable arrangements for releasably attaching the exterior cover  1000  to the adapter  250  may be used, such as those given above, by arranging matching male and female threads on the exterior cover engaging surfaces  285  and the interior surface  1010 , or other suitable releasably attaching structures. 
     Referring to  FIG. 1 , a decorative lug nut and bolt cover system  5  may comprise a nut cover means  35  for gripping a lug nut  100 ; an adapter means  25  for engaging the nut cover means  35 ; and an exterior cover means  10  for (a) releasably attaching to the exterior cover end  27  of the adapter means  25 , (b) compressing the nut end  29  of the adapter means  25 , and (c) applying a compression force to the nut cover means  35  via compressing the nut end  29  of the adapter means  25 . 
     Referring to  FIGS. 5-7 , a decorative lug nut and bolt cover system may comprise a nut cover means  350  for gripping a lug nut; an adapter means  250  for engaging the nut cover means  350 ; and an exterior cover means  1000  for (a) releasably attaching to an exterior cover end  260  of the adapter means  250 , (b) compressing a nut end  270  of the adapter means  250 , and (c) applying a compression force to the nut cover means  350  via compressing the nut end  270  of the adapter means  250 . 
     It will be obvious to those having skill in the art that many changes may be made to the details of the above-described embodiments without departing from the underlying principles of the invention. The nut cover, adapter, and/or exterior cover may take a variety of shapes and sizes to create a compressive force on the nut cover to grip a nut. The scope of the present invention should, therefore, be determined only by the following claims.