Patent Abstract:
Fastening devices are disclosed herein with variations on how said devices resist loosening or un-fastening from a structure or structures. In some examples, the fastening devices accomplish the removal resistant condition by using a spring component engaging ridged surfaces. The spring component generally consists of a spring ring conveniently coiled to a canting position. One exemplary design is characterized by incorporating a screw element with its head underside surface being ridged and a lock element with a ridged topside surface and engaging the two ridges surfaces. Another exemplary design is characterized by a screw element having a head outer sidewall being ridged for cooperating with a bore having a ridged inner sidewall. The bore can be part of a first body or structure or a lock element.

Full Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    This is a regular utility application of provisional application Ser. No. 61/546,332, filed Oct. 12, 2011, and of provisional application Ser. No. 61/478,829, filed Apr. 25. 2011. The contents of both provisional applications are expressly incorporated herein by reference. 
     
    
     FIELD OF ART 
       [0002]    The present devices, assemblies and methods relate to threaded fastening devices and more specifically those that include removal resistant features. 
       BACKGROUND 
       [0003]    There are many applications where removal resistant fastening devices are desired, such as in the medical field, aerospace, automotive, and electrical, which includes electrical distribution, consumer electronics, etc. Threaded fasteners can become loose or undone due to vibration, thermo-cycling, or by physical contact, in advertent or otherwise. Another exemplary application is in spinal plates, where screws are used to fix the plate to the vertebrates, i.e., to fix a first body to a second body. In due course, the bone screws may loosen over time due to vibration and/or spine movement. 
       SUMMARY 
       [0004]    The present devices and assemblies include loosen resistant screws, which utilize a canted coil spring and related methods. 
         [0005]    Multiple removal resistant screw fastening devices are disclosed herein. The devices use a spring component engaging ridged surfaces to resist loosening. An exemplary design comprises a screw, a first body to be fastened to a second body, a lock element, such as a washer, prevents the screw from rotation with respect to the first body, and a spring element positioned in contact with the lock washer in the first body. In one example the screw head underside and the lock element topside are ridged surfaces that engage one another. The spring adds a biasing force to further ensure engagement between the ridged surfaces. This ridged engagement prevents the screw from removal. Another exemplary design includes a screw, a first body fastened to a second body, and a spring element. The first body bore diameter is larger than the screw head diameter. The first body bore inner sidewall and the screw head outer sidewall are ridged surfaces that engage the spring element, which is placed within the space available between the bore sidewall and the screw head. In an alternative embodiment, a ring element is disposed between the spring and the bore sidewall and the spring element. The ring element comprises a ridged surface for engaging the spring. 
         [0006]    In exemplary embodiments, a removal resistant fastening device for securing a first body to a second body is provided. The device can comprise a screw element, a lock element having a topside surface and an underside surface, and a spring element. The screw element comprises a head and a shank. The screw element and the lock element both comprise ridged surfaces that, at least in part, engage. The ridged surface of the screw element is located on an underside surface of the head and the ridged surface of the lock element is located on the topside surface. The spring element is configured to bias the lock element towards the head. 
         [0007]    The removal resistant fastening device as noted wherein the lock element has at least one protruding member that fits within a gap in a surface of the first body. 
         [0008]    The removal resistant fastening device as noted wherein the head of the screw element comprises a topside surface that is slotted and said lock element has a bendable lateral tab that fits within a gap in the first body and in a slot of the topside surface of the head. 
         [0009]    In another exemplary embodiment, a removal resistant fastening assembly is provided. The assembly comprises a screw element, a spring element, a first body, and a second body. The screw element comprises a head that is larger in diameter than a shank. The head comprises an outer sidewall and the first body having a bore inner sidewall having radially-arranged ridged surfaces. The spring element is positioned in a space defined between the head and the bore inner sidewall. The screw element is rotatable in a first direction when turning at a first force and rotatable in a second direction which is opposite the first direction when turning at a second force, which is larger than the first force. 
         [0010]    The removal resistant fastening assembly as noted, wherein the outer sidewall of the head is tapered relative to an axis of the shank. 
         [0011]    The removal resistant fastening assembly as noted wherein the outer sidewall of the head has a lip that extends radially away from the shank. 
         [0012]    The removal resistant fastening assembly as noted wherein the first bore of the first body is tapered relative to an axis of the shank. 
         [0013]    The removal resistant fastening assembly as noted, wherein the bore of the first body has a lip that extends radially inwardly of a perimeter of the bore. 
         [0014]    In a further example, a removal resistant fastening assembly is provided. The assembly comprising a screw element, a lock element, a spring element and a first body fastened to a second body. The screw element comprises a head that is larger in diameter than a shank. The lock element is placed about a bore of the first body and prevented from rotating relative to the first body by positioning a protruded member of the lock element into a gap in the first body. The head comprises an outer sidewall having a ridged surface and the lock element comprising an inner sidewall having a ridged surface; the two ridged surfaces engaging, at least in part, one another. The spring component is fitted in a space defined between the head and the lock element and allows the screw element to turn only in one direction when turning at a first force and in a second direction, which is opposite the first direction, when turning at a second force, which is greater than the first force. 
         [0015]    The removal resistant fastening assembly as noted, wherein the outer sidewall of the head is tapered relative to an axis of the shank portion. 
         [0016]    The removal resistant fastening assembly as noted, wherein the outer sidewall of the head has a lip. 
         [0017]    The removal resistant fastening assembly as noted, wherein the inner sidewall of the lock element is tapered. 
         [0018]    The removal resistant fastening assembly as noted wherein the inner sidewall of the lock element has a lip. 
         [0019]    Features of the present description further include a removal resistant fastening device for securing a first body to a second body comprising: a screw element comprising a screw head having a screw head side wall and a shank; a canted coil spring comprising a plurality of coils; a housing comprising a bore having a side wall defining a first opening of a first diameter and a second opening of a second smaller diameter; the first opening having the screw head disposed therein and the second opening being a through hole and having the shank passing therethrough; wherein at least one of the screw head and the bore of the housing comprises surfaces having ridges; and wherein at least ten coils of the plurality of coils engage the ridges. 
         [0020]    The removal resistant further comprising a lock element having a topside surface an underside surface, and a through bore: and wherein the lock element is biased by the canted coil spring. 
         [0021]    The removal resistant fastening device, wherein the topside surface, the bottom side surface, part of a surface forming the through bore of the lock element, or all the topside surface, the bottom side surface; and the surface forming the through bore have ridges formed thereon. 
         [0022]    The removal resistant fastening device, wherein the lock element further comprises a tab having a length that is longer than a width. 
         [0023]    The removal resistant fastening device, wherein the screw head comprises a slot for receiving a tool to turn the screw head. 
         [0024]    The removal resistant fastening device, wherein the screw head side wall or the side wall of the bore is tapered relative to an axis defined by the shank. 
         [0025]    The removal resistant fastening device, wherein the screw head or the bore of the housing has a lip extending therefrom. 
         [0026]    The removal resistant fastening device, wherein the canted coil spring is located between the screw head and a lock element. 
         [0027]    Features of the present description further include a method for using a removal resistant fastening device for securing a first body to a second body. The method comprising: providing a screw element comprising a screw head having a screw head side wall and a shank; providing a canted coil spring comprising a plurality of coils; placing the screw element through a housing said housing comprising a bore having a side wall defining a first opening of a first diameter and a second opening of a second smaller diameter; the first opening having the screw head disposed therein and the second opening being a through hole and having the shank passing therethrough; wherein at least one of the screw head and the bore of the housing comprises surfaces having ridges; and causing at least ten coils of the plurality of coils to engage the ridges. 
         [0028]    The method further comprising threading the shank into a threaded bore. 
         [0029]    The method further comprising placing a lock element into the bore and causing the canted coil spring to bias the lock element. 
         [0030]    The method further comprising removing the screw element from the housing using a removal force, and wherein the removal force is higher than a force to secure the screw element so that the screw head is within the bore of the housing. 
         [0031]    The method further comprising the step of engaging the at least ten coils of the plurality of coils to a plurality of ridges located on the lock element. 
         [0032]    The method further comprising the step of bending a tab formed on the lock element. 
         [0033]    The method further comprising the step of providing a tapered surface on the screw head side wall or the side wall of the bore, the tapered surface being tapered relative to an axis defined by the shank. 
     
    
     
       BRIEF DESCRIPTION OF DRAWINGS 
         [0034]    These and other features and advantages of the present device, system, and method will become appreciated as the same becomes better understood with reference to the specification claims and appended drawings wherein: 
           [0035]      FIGS. 1A-1B  show a top view and a cross section of a fastening device in its unlocked configuration. 
           [0036]      FIGS. 2A-2B  show top view and a cross section of a fastening device in its unlocked configuration. 
           [0037]      FIGS. 3A-3B  show a top view and a cross section of a fastening device in its locked configuration. 
           [0038]      FIGS. 4A. 4B , and  4 C show different views of a castellated slotted screw shown in  FIGS. 1A-3B . 
           [0039]      FIGS. 5A ,  5 B, and  5 C show different views a serrated face washer shown in  FIGS. 1A-3B . 
           [0040]      FIGS. 6A-6B  show a top view and a cross section of another fastening device. 
           [0041]    FIG.  6 B 1  shows an alternative embodiment of the fastening device of  FIGS. 6A-6B . 
           [0042]      FIG. 6C  is an enlarged view of an area or section of the fastening device illustrated in  FIG. 6A . 
           [0043]    FIG.  6 C 1  is an alternative embodiment of  FIGS. 6A. 6B , and  6 C. 
           [0044]    FIG.  6 C 2  is an alternative embodiment of  FIGS. 6A ,  6 B, and  6 C. 
           [0045]      FIGS. 6D-6G  show four cross sections corresponding to four different alternative configurations of the fastener device depicted in  FIG. 6B . 
           [0046]      FIG. 6H  is an enlarged view of an area or section of one of the cross sections illustrated in  FIG. 6E . 
           [0047]    FIG.  6 H 1  is an enlarged view of an area or section of one of the cross sections illustrated in  FIG. 6D . 
           [0048]      FIG. 6I  is an enlarged view of an area or section of one of the cross sections illustrated in  FIG. 6G . 
           [0049]      6 I 1  is an enlarged view of an area or section of one of the cross sections illustrated in  FIG. 6F . 
           [0050]      FIGS. 7A-7B  show a top view and a cross section of another fastening device provided in accordance with aspects of the present device assembly and method. 
           [0051]    FIG.  7 B 1  is an alternative embodiment of the device of  FIGS. 7A-7B . 
           [0052]      FIG. 7C  is an enlarged view of an area or section of one of the cross sections illustrated in  FIG. 7A . 
           [0053]      FIGS. 7D-7E  show a top view and a cross section of another fastening device provided in accordance with aspects of the present device assembly and method. 
           [0054]      FIGS. 7F-7I  show four cross sections corresponding to four different alternative configurations of the fastener device depicted in  FIGS. 7D-7E . 
           [0055]      FIG. 7J  is an enlarged view of an area or section of one of the cross sections illustrated in  FIG. 7G . 
           [0056]      7 J 1  is an enlarged view of an area or section of one of the cross sections illustrated in  FIG. 7F . 
           [0057]      FIG. 7K  is an enlarged view of an area or section of one of the cross sections illustrated in  FIG. 7I . 
           [0058]    FIG.  7 K 1  is an enlarged view of an area or section of one of the cross sections illustrated in  FIG. 7H . 
           [0059]      FIGS. 8A-8B  show a top view and an elevation of a screw shown in  FIGS. 7F-7I . / 
       
    
    
     DETAILED DESCRIPTION 
       [0060]    The detailed description set forth below in connection with the appended drawings is intended as a description of the presently preferred embodiments of fastening connectors or fastener devices provided in accordance with aspects of the present device, system and method and is not intended to represent the only forms in which the present device, system, and method may be constructed or utilized. The description sets forth the features and the steps for constructing and using the embodiments of the present device, system, and method in connection with the illustrated embodiments. It is to be understood, however, that the same or equivalent functions and structures may be accomplished by different embodiments that are also intended to be encompassed within the spirit and scope of the present disclosure. As denoted elsewhere herein, like element numbers are intended to indicate like or similar elements or features. 
         [0061]    With reference now to  FIG. 1A  and  FIG. 1B , a top view and a cross section of a fastening device  20  in an unlocked configuration are shown. The fastening device  20  comprises a slotted screw  22  comprising a head  24  and a threaded shaft or shank  26 . The upper surface  28  of the head  24  is slotted, such as with a single channel or cross-channels or with any number of grooves or channels for mating with a corresponding turning device or instrument for rotating the screw. The slots may also be used to engage with a tab, as further discussed below. In the embodiment shown, the underside or bottom surface  30  of the head  24  incorporates raised serrated ridges  32  such as bumps, grooves, ridges, channels, or castellated surfaces. The slots on the upper surface  28  may have similar serrated ridges  32  as the underside surface  30 . In another embodiment, the slots on the upper surface and the serrated grooves on the underside surface differ in configuration. As used herein, the terms “top”, “under”, “first”, or “second” seekto merely define different parts or sections of a structure and are subject to different viewing perspectives. Thus, unless indicated otherwise, these terms are not structurally limiting. 
         [0062]    The connector  20  further includes a lock element  34  which may be a washer a ring, or a flange, comprising a tab  36 , which may be unitarily formed with the washer or separately formed and subsequently attached to the lock element. The lock element has a bore for receiving the shank. In one example, the washer  34  incorporates a matching serrated face as the serrated face  32  of the underside surface of the head  24 . When the washer  34  is placed at the bottom of the bore  38  of the housing  40  so that its serrated ridges mate with the serrated ridges  32  of the screw  22  and pressure or load is applied across the two surfaces, the washer and the head cannot rotate relative to one another. As shown, the housing bore  38  has a first opening for receiving the screw head and a second through opening for allowing the shaft or shank  26  to pass therethrough. In some examples, the housing  40  may embody a plate, a flange a bracket, or other structures, which may generically referred to herein as a first body, to be secured by the fastener device of the present device, system, and method to another body. i.e., a second body. For example, the second body may be a pipe, an equipment, a plate, an engine, a bone, a desk, a base, a door, or any component that the screw  22  may or can be secured to or against. In one example a spring groove  42  is incorporated in the bore  38  of the housing  40 . The spring groove  42  is sized to receive a canted coil spring  44  and allows a portion of each coil of the canted coil spring to extend beyond the groove to exert spring pressure against the washer  34 . The spring  44  is preferably an axial canted coil spring, as understood by a person of ordinary skill in the art. In other embodiments, the spring is a radial canted coil spring with the spring major axis rotated to be non-parallel to the shank  26 , i.e., at an angle. Thus, in addition to compression force caused by the shaft engaging the housing and exerting pressure between the head and the washer, the spring further biases the washer towards the head to ensure engagement between the mating serrated surfaces. The fastener device can be said to be spring loaded. 
         [0063]    In one embodiment, the housing  40  is provided with a guide slot, channel, or groove  46  ( FIG. 1A ), generically a gap, for receiving the tab  36  on the washer  34 . The guide slot  46  confines the tab  36  within the width of the slot to limit rotation of the tab  36  and therefore rotation of the washer  34 . As shown, the tab  36  has a first tab section  48  formed at an angle to a second tab section  50 . The second section  50  may be formed by bending the tab from the first section. The combination tab and washer may be formed by punching or machining from a metallic sheet or by other known fabrication techniques. Following installation, the extended section of the second tab section  50  may be bent over to engage one of the grooves or channels on the upper surface  28  of the head, as further discussed below. 
         [0064]      FIGS. 2A and 2B  show the same connector  20  as the connector of  FIGS. 1A and 1B  but with the cross-sectional view from a different perspective, as shown by line A-A in  FIG. 2A . As shown, the bore  38  has a diameter that is slightly larger than the diameter of the head  24 . In another embodiment, the bore or the head may incorporate a slot or groove for receiving an O-ring (not shown) to seal portions of the connector  20  below the O-ring. 
         [0065]    As understood, aspects of the present connector device  20  comprises a housing comprising a bore  38  having a bore side surface  52  and a bore bottom surface  54  having a groove  42  formed therein containing a canted coil spring  44 . A washer  34  having an upper serrated surface is placed in the bore and in contact with a head  24  of a screw  22  having a bottom serrated surface. More generically, an aspect of the present connector device comprises a canted coil spring that preloads a washer against a bottom surface of a screw head. The washer and the head may be prevented from relative rotation by incorporating matching serrated surfaces on the washer and the head. In a further aspect of the present device system and method, a tab is incorporated on the washer and held stationary from angular rotation relative to the shank by placing the tab in a slot formed in the housing. In another example, the washer is prevented from angular rotation relative to the bore. 
         [0066]    Refer again to  FIGS. 1B and 2B , the head  24  projects above the upper surface  56  of the housing  40 . In another example the head  24  is even or level with the upper surface  56 . In still yet another example the head  24  is recessed within the bore  38  and is located below the upper surface. 
         [0067]      FIGS. 3A and 3B  show a top view and a cross sectional side view of the fastening device  20  of  FIGS. 1A-2B  in its locked configuration. The device  20  may be locked by bending the tab  36  so that a portion of the second tab section  50  is folded and engages one of the slots  58  on the upper surface of the head. The engagement between the tab  36  and the head prevents rotation of the washer relative to the screw. Furthermore, by positioning in the guide slot  46  of the housing  40  the tab  36  is prevented from rotating relative to the housing. 
         [0068]      FIGS. 4A. 4B , and  4 C show a top view, a bottom view and an elevation view of the screw  22  of the fastening device  20  depicted in  FIGS. 1A to 3B . The head  24  of the disclosed screw includes a castellated slotted topside  28  and serrated ridges  32  in its underside  30 . One of the multiple slots  58  on the topside is configured to receive a bent portion of the tab  36  of the fastening device  30  when such device is in its locked configuration. The number of slots  58  and serrated ridges  32  may be selected to facilitate easy and simple engagement along a wide angular position of the head. 
         [0069]      FIGS. 5A ,  5 B, and  5 C show a top view, a bottom view, and an elevation view of the washer  34  provided in accordance with the present device, system, and method. The washer  34  has an attached tab  36 , which has a first tab section  48  and a second tab section  50  formed at an angle to the first tab section. The washer  34  has an underside surface  60  an upper surface  64 , and a bore  62  extending therebetween. In one example the underside surface  60  is generally flat or smooth, although grooves or other surface features may be incorporated. The upper surface  64  comprises a plurality of serrated ridges  66  that match the underside profile of the screw head  24  of the fastening device  20 . The second tab section  50  is shown unbent. The serrated ridges  66  of the washer  34  and the serrated ridges  32  of the screw  22  are configured to mate or mesh, similar to gear surfaces. 
         [0070]      FIG. 6A  shows a top view of a fastening device  68  provided in accordance with another aspect of the present device, system, and method.  FIG. 6B  shows a cross section side view of the device  68  taken along line A-A of  FIG. 6A . The fastening device  68  comprises a screw  70  having a head  72  and a threaded shaft or shank  74  and a plurality of ridges  76  formed along the outer sidewall  78  of the head  72 . The head  72  incorporates a hex slot  80  for use with a matching rotating instrument to rotate the screw. However, other shaped slots may be incorporated without deviating from the scope of the present device, system, and method. The screw  70  projects through a bore  82  of a housing  84 , which has an upper bore section  86  comprising a sidewall  88  defining a first opening for receiving a screw head and a bottom wall  90 . The bottom wall  90  further comprises a second opening, which has a through hole for allowing the shank  74  to pass therethrough. As shown the upper bore section  86  is substantially wider than the screw head diameter for receiving a canted coil spring  92  therebetween. In one example, the sidewall surface  88  comprises ridges  94  formed on its sidewall surfaces for engaging the plurality of coils on the spring  92 . When mounted as shown in  FIGS. 6A and 6B , the canted coil spring  92  simultaneously engages the ridges  76  on the head  72  of the screw  70  and the ridges  94  of the sidewall surface  88  of the upper bore section  86 . As the housing  84  is fixed from rotation, the engagement between the spring and the bore and the engagement between the spring and the screw head fix the screw  70  from rotating relative to the bore. The engagement produces a removal resistant fastening device. The spring also exerts a constant load against the screw head and is understood to eliminate screw vibration and play within the locking mechanism. Thus, an aspect of the present device, system, and method is understood to include a connector device comprising a screw comprising a head and a shank, a head side wall comprising a plurality of ridges sized and dimensioned to engage a plurality of coils of a canted coil spring. In one example, the spring is a radial canted coil spring. However, the space between the head  72  and the upper bore section  86  which defines a spring groove, may be angled to accept an axial canted coil spring. The present device, system, and method further include a housing having a bore and a sidewall surface of the bore comprising a plurality of ridges, and wherein the plurality of coils engage the plurality of ridges on the sidewall of the bore and the ridges on the head  72 . 
         [0071]    FIG.  6 B 1  shows a cross section side view of an alternative fastener device  68 ′, which is an alternative embodiment of the device  68  of  FIGS. 6A and 6B . In the present embodiment the upper bore section  86  of the housing  84 ′ is modified to include a groove  67  formed on or in the bottom wall  90  of the housing  84 ′, which presents a modified configuration from the housing of  FIG. 6B . In one embodiment, the groove  67  is square and comprises two generally parallel sidewalls and a bottom wall that is orthogonal to at least one of the two sidewalls. In another embodiment, the bottom wall is tapered relative to the at least one of the two sidewalls. A canted coil spring  92 ′, such as an axial canted coil spring, is located in the groove  67  and is biased against the bottom wall of the groove  67  and the bottom surface of the head  72 . The added spring  92 ′ therefore provides additional removal resistance to limit or restrict the screw  70  from backing out of the housing  84 ′. The two springs  92 ,  92 ′ may be referred to as a first spring and a second spring. 
         [0072]      FIG. 6C  is an expanded view of a section or area of the fastening device  68  illustrated in  FIG. 6A . As shown, part of the canted coil spring  92  is positioned between the housing bore section  86  and the screw head  72 . The coils of the canted coil spring fit or engage with the ridges  94  of the inner sidewall  88  of the housing bore section as well as those of the outer sidewall  78  of the screw head  72 . 
         [0073]    FIG.  6 C 1  is an alternative configuration of the ridges  94  of the housing  84  and the ridges  76  of the screw head  72  of  FIG. 6C . Among other things, a greater number of ridges are incorporated on the housing and the screw head for example a greater density of ridges per unit space. The greater number of ridges  76 ,  94  allow more of the individual coils  91  of the canted coil spring  92  to engage the individual ridges  76 ,  94 . In one example, more than 75% of the coils, such as 80% or  85 % of the coils, engage the individual ridges. The screw head is locked in this configuration and the backlash (the amount of allowable back rotation between the current state and the next “click” or locked state) is minimized. 
         [0074]    FIG.  6 C 2  is an alternative configuration of the embodiment of FIG.  6 C 1 . In the present embodiment, the ridges  94  of the housing  84 , the ridges  76  of the screw head  72 , the coil spacing of the spring  92  or all three are modified so that the some of the individual coils do not engage the individual ridges  76 ,  94  of the housing  84  and the screw head  72 . In one embodiment, approximately half of the ridges  94  of the housing  84  are not engaged by any of the individual coils  91  of the spring  92 . This figure shows some coils between two ridges and some coils near the ridge peaks. This configuration further reduces backlash since there will always be some coils that are biasing against back rotation and the amount of rotation required to get to the next locked state is reduced. 
         [0075]      FIGS. 6D-6G  show four cross sections of four alternative configurations of the fastener device  68  depicted in  FIGS. 6A-6C . With specific reference to  FIG. 6D , the fastener device  96  is shown with a screw head  98  having a ridged outer sidewall  98 ′, which is tapered inwardly in the direction of the shaft, having a spring  92  biased thereto and against a side wall of the housing  97 . An alternative configuration is shown in  FIG. 6E  and includes a fastener device  100  with a screw head  102  having a lip  104  at the top of the ridged tapered outer sidewall of the screw head. The lip  104  further ensures retention of the spring  92  within the spring groove  106  of the housing  107 . Another alternative configuration shown in  FIG. 6F  and it includes a fastener device  108  with a screw head  110  located inside a bore  112  of a housing  114  having ridged inner sidewall  116  with a taper. In the  FIG. 6F  embodiment, the sidewall of the screw head is generally square, i.e., non-tapered. Alternative configuration shown in  FIG. 6G  includes a fastener device  118  with a screw head  120 , similar to the screw head  110  of  FIG. 6F , having a lip  122  at the top of the ridged inner sidewall  116  of the bore section  124  of the housing  113 . 
         [0076]    Thus, as disclosed, aspects of the present device system, and method include a fastener device comprising a screw having a head and a shaft, and wherein the head comprises an exterior sidewall comprising a plurality of ridges and wherein the exterior sidewall is either tapered or non-tapered. In a specific example, a lip is incorporated at the tapered sidewall, adjacent the top surface of the head. In another example, the fastener device is positioned inside a bore of a housing and wherein the bore is tapered. In one example, the bore of the housing comprises a lip at the tapered sidewall adjacent the top wall. 
         [0077]      FIG. 6H  shows an expanded view of an area or section of the alternative configuration shown in  FIG. 6E , which shows the lip  104  at the top of the ridged outer sidewall of the screw head. The lip is configured to assist with retaining the canted coil spring in the cavity defined by the housing bore section and the screw head. 
         [0078]    FIG.  6 H 1  shows an expanded view of an area or section of the alternative configuration shown in  FIG. 6D , which shows a tapered sidewall  98 ′ of the screws head  98 , the spring  92 , and the sidewall  97 ′ of the housing  97 . 
         [0079]      FIG. 6I  shows an expanded view of an area or section of the alternative configuration in  FIG. 6G , which shows the lip  122  at the top of the ridged inner sidewall of the bore section  112  of the housing  113 . The lip is configured to assist in retaining the canted coil spring in the cavity defined by the screw head and the said housing bore section. 
         [0080]    FIG.  6 I 1  shows an expanded view of an area or section of the alternative configuration in  FIG. 6F  which shows a tapered sidewall  116 ′ of the housing  114 , the spring  92 , and the sidewall of the screw head  110 . 
         [0081]      FIGS. 7A  and  FIG. 7B  show a top view and a cross section of a fastener device  126  comprising a screw  128  comprising a head  130  and a shank  132 . The head  130  comprises a plurality of ridges  134  formed along the outer sidewall  136  thereof. The head  130  is located in a bore of a housing  138 , which has a ring or lock element  140  received therein having an inner diameter wider than the screw head diameter. In one example, the ring  140  comprises ridges  142  formed along its inner sidewall for mating with the plurality of coils of the canted coil spring  92 . The plurality of coils of the canted coil spring  92  also engages the ridges  134  of the outer sidewall  136  of the screw head  130 . In one example, the ring  140  comprises a tab  144  positioned in a slot  146  ( FIG. 7A ) formed in the housing  148 . The ring  140  prevents the screw  128  from rotating relative to the housing by means of the tab  144  engaging the slot  146  and by the engagement between the ridged surfaces  134 .  142  and the spring  92 . 
         [0082]    FIG.  7 B 1  shows a cross section side view of an alternative fastener device  126 , which is an alternative embodiment of the device  126  of  FIGS. 7A and 7B . In the present embodiment, the upper bore section of the housing  138 ′ is modified to include a groove  67  formed on or in the bottom wall of the housing  138 ′, which presents a modified configuration from the housing  138  of  FIG. 7B . In one embodiment, the groove  67  is square and comprises two generally parallel sidewalls and a bottom wall that is orthogonal to at least one of the two sidewalls. In another embodiment, the bottom wall is tapered relative to the at least one of the two sidewalls. A canted coil spring  92 ′, such as an axial canted coil spring, is located in the groove  67  and is biased against the bottom wall of the groove  67  and the bottom surface of the head  130 . The added spring  92 ′ therefore provides additional removal resistance to limit or restrict the screw  128  from backing out of the housing  138 ′ and away from the holding ring  140 . 
         [0083]      FIG. 7C  shows an expanded view of an area or section of the fastening device  126  of  FIGS. 7A-7B . As shown, part of the canted coil spring  92  is positioned between the ring  140  and the screw head  130 . The plurality of coils of the canted coil spring engage the ridges of the inner sidewall of the ring as well as those of the outer sidewall of the screw head. 
         [0084]    Thus, aspects of the present device, system and method include a fastener comprising a shank and a head located inside a bore of a housing and wherein a ring and a canted coil spring are located concentrically inside the bore with the head. Further features of the present device, system, and method are ridged surfaces formed on the ring and on the head for engaging a plurality of coils of the canted coil spring. The engagement between the spring and the ridged surfaces are configured to fix angular rotation, or at least resist angular rotation, of the fastener relative to the housing. To further facilitate fixing the angular rotation, or at least resist angular rotation, of the fastener, a tab is incorporated with the ring for engaging a slot formed in the housing. In yet another aspect of the present device, system and method, a stationary housing having a bore is provided, a screw comprising a head and a shank positioned in the bore, and wherein the screw is fixed from angular rotation, or at least resist angular rotation, relative to the housing by a spring concentrically placed with the head. In a specific example, a ring is provided with the spring to fix the angular rotation of the screw relative to the housing. In certain embodiments the head and the ring both have ridges surfaces for engaging a plurality of coils on the spring. Another aspect of the present device, system, and method is a provision for forming the housing, the spring, the screw and, where incorporated, the ring from implantable grade materials for medical applications. Preferably, the implantable materials are metallic or metallic-based materials. 
         [0085]    In addition to the present devices and assemblies are methods for forming the devices and assemblies and methods for using the devices and assemblies described elsewhere herein. 
         [0086]      FIG. 7D  shows a top view of an alternative fastener device  160  while  FIG. 7E  shows a cross sectional view of the device  160  taken along line A-A of  FIG. 7D . The present device  160  is similar to the device of  FIGS. 7A-7C  with the following exceptions. The housing bore  170  of the housing  172  may be non-circular, for example oval, elliptical, square star-shaped or rectangular to name a few. The ring  162  may be similarly shaped exteriorly so that the ring cannot rotate inside the bore or relative to the housing. Optionally a tab  144  and a slot  146  may be incorporated with the ring and the housing, respectively, but not necessary to prevent relative rotation between the ring and the housing. The screw  164  is shown with a head  166  and a threaded shank  168 . The interior bore of the ring and the screw head should both be circular or generally circular to enable rotation of the screw relative to the ring for installation. 
         [0087]      FIGS. 7F-7I  are alterative embodiments of the fastener device  126  of  FIGS. 7A and 7B . The fastener device  176  depicted in  FIG. 7F  incorporates a ridged outer sidewall  178  on the screw head  180  that is also tapered.  FIG. 7G  shows a fastener device  182  that includes a lip  184  at the top of the ridged outer sidewall  186  of the screw head  188 . The ridged outer sidewall  186  may be non-tapered or tapered.  FIG. 7H  shows a fastener device  190  that incorporates a ridged inner sidewall  192  on the ring  194  that is also tapered.  FIG. 7I  shows a fastener device that incorporates a lip  198  at the top of the ridged inner sidewall  200  of the ring  202 , which may be tapered or non-tapered. 
         [0088]      FIG. 7J  shows an expanded view of an area or section of the fastener device  182  of  FIG. 7G . The lip  184  at the top of the ridged outer sidewall  186  of the screw head is clearly shown. The lip  184  assists to retain the canted coil spring  92  in the cavity defined by the ring and the screw head. 
         [0089]    FIG.  7 J 1  shows an expanded view of an area or section of the fastener device  176  of  FIG. 7F . As clearly shown, the screw head  180  has a tapered side wall surface pushed against the spring  92 , which is pushed against the ring  160 . The tapered side wall surface of the screw head assists to retain the canted coil spring  92  in the cavity defined by the ring and the screw head. 
         [0090]      FIG. 7K  shows an expanded view of an area or section of the fastener device  196  of  FIG. 7I . The lip  198  at the top of the ridged inner sidewall  200  of the ring is clearly shown. The lip  198  assists to retain the canted coil spring in the cavity defined by the screw head and the ring. 
         [0091]    FIG.  7 K 1  shows an expanded view of an area or section of the fastener device  190  of  FIG. 7H . As clearly shown, the ring  192  has a tapered side wall surface puhsed against the spring  92 , which is pushed against the side of the screw head  166 . The tapered side wall surface of the ring assists to retain the canted coil spring  92  in the cavity defined by the ring and the screw head. 
         [0092]      FIG. 8A  and  FIG. 8B  show a top view and an elevation view of a screw  206  usable with the fastening devices depicted in the various figures and described elsewhere herein. The screw comprises a head  208  and a shank  210  comprising exterior threads  212 . The head  208  comprises a hex bore  214  for use with a matching turning tool and exterior ridges  216  formed along the outer sidewall  218  of the head  208 . The ridges are configured to engage with a plurality of coils of a canted coil spring, as described elsewhere herein. 
         [0093]    Although limited embodiments of the fastening assemblies and their components have been specifically described and illustrated herein, many modifications and variations will be apparent to those skilled in the art. For example, the various fastening assemblies may have different lengths, diameters, and made from different materials than described, etc. Furthermore, it is understood and contemplated that features specifically discussed for one fastener embodiment may be adopted for inclusion with another fastener embodiment, provided the functions are compatible. For example, while an irregular shaped housing bore may be discussed with reference to  FIGS. 7D and 7E , it may be used in another embodiment shown, for example with  FIG. 3B  or  6 E. Furthermore, it is understood that the threaded shanks described herein are to be threaded into another structure or body. For example, the housing  40  described with reference to  FIG. 2B  is understood to be fastened to a second body  51  (shown in phantom) by threading the shank  26  into that second body. Thus, the fastener assemblies described herein are understood to be usable to fasten a first housing or structure to a second housing or structure. Accordingly, it is to be understood that the fastener assemblies and their components constructed according to principles of the disclosed device, system, and method may be embodied other than as specifically described herein. The disclosure is also defined in the following claims.

Technology Classification (CPC): 5