Patent Publication Number: US-2009232616-A1

Title: Friction Lock Bolt

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
     This application claims benefit of U.S. Provisional Application No. 61/034,822 filed Mar. 7, 2008, which is incorporated herein by reference for all purposes. 
    
    
     FIELD OF TECHNOLOGY 
     Exemplary embodiments of the invention generally relate to a fastener, such as a bolt, and methods of using the bolt. In a non-limiting implementation, the bolts are used in systems to securely mount a panel to a rail. 
     BACKGROUND OF EXEMPLARY EMBODIMENTS OF THE INVENTION 
     Fasteners, such as bolts, are used to secure two objects together. In one example, a bolt may be used to mount a panel to a support structure, such as mounting a solar panel onto a rail. In such cases, the rail may be, in turn, mounted to a secure surface, such as roof footings, footing grids, roofs, poles, frames, surfaces, or other objects. 
     Over time, the bolt may loosen, particularly when it is exposed to varying forces induced or caused by wind, snow, rain, and other elements of weather. The loose bolt is problematic because the panel may no longer be securely held to the rail or support structure. 
     Furthermore, the current design of the bolts tends to allow the bolts to fall out, slip or move when inserted into a slot of a rail for the purpose of securing a panel or other device. As such, an installer may need to use both hands to steadily position a bolt after placing the bolt in the slot and before placing the panel on the rail and securing the assembly by tightening a nut around the bolt. This is due, in part, because there is no compressing force between the interior surfaces of the slot and the head of the bolt to initially hold the bolt in place. Accordingly, the bolts complicate the installation of the panels and other devices and make the installation more time consuming. 
     As the use of solar panels to generate all or part of the electrical needs for home and industry increases, demand has escalated for a solar panel mounting system that not only is structurally rigid, weather resistant, and easy to install, but also is easy to maintain and is structurally secure for an extended period of time. Therefore, a new and useful bolt that is capable of easily and securely mounting solar panels onto a rail is needed. 
     SUMMARY OF EXEMPLARY EMBODIMENTS OF THE INVENTION 
     An object of an illustrative, non-limiting embodiment of the present invention is to overcome the above and other problems and disadvantages associated with the current design of bolts and other fasteners. Also, the present invention is not required to overcome the disadvantages described above, and exemplary embodiments of the present invention may overcome other disadvantages or may not overcome any disadvantages. 
     In one embodiment, the present invention relates to a bolt that facilitates a more secure and easy mounting of a panel onto a support structure. In this embodiment, an elastomeric element is provided on a head of the bolt so that the elastomeric element is compressed against an opposing surface of the support structure during an assembly or installation process. The support structure has upper and lower portions that define a slot that can accept the head of the bolt. The bolt is inverted and inserted into the slot so that the elastomeric element compresses against the lower portion of the support structure and presses the head of the bolt against the upper portion. This results in creating friction between the bolt, which holds the bolt steady during assembly or installation and prevents the bolt from loosening after the panel is mounted. 
     In one example, after securing the bolt to the support structure at a desirable location on the structure, the panel may be mounted onto the support structure. A clamp is placed over at least a portion of the panel and the bolt so that the bolt extends through the clamp. A flange nut may be used to tighten the clamp down towards the support structure and secure the panel. 
     In another embodiment, the bolt has a dog-point on the end of the bolt to facilitate placement of a nut on the bolt. 
     In some embodiments, the bolt includes a head with a spring that compresses during installation of the bolt. 
     In still another embodiment, the bolt includes a mechanism that prevents the bolt from turning in a direction, which loosens the bolt, after installation. 
     Embodiments of the invention also provide a method of installing a solar panel onto a rail. In one implementation, the bolt engages the panel and the rail and secures the panel to the rail. 
     Other embodiments may relate to a nut or other fastener having the same elastomeric spring material to create the same functionality. 
     While several embodiments of the bolt and nut are explained in connection with securing a solar panel to a rail, they may be used in other applications where an opposing surface would compress the elastomeric element and provide for a more secure and easy installation process. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS  
       The above and other objects and advantages of illustrative, non-limiting embodiments of the present invention will become more apparent by describing them in detail with reference to the attached drawings in which: 
         FIG. 1  shows a perspective view of an embodiment of a bolt. 
         FIG. 2  shows a cross-sectional view of the bolt of  FIG. 1  in an embodiment of a support structure. 
         FIGS. 3A to 3C , respectively, show a bottom, side, and top views of an embodiment of the bolt. 
         FIGS. 4A to 4D , respectively, show two side views, a top view, and a bottom view of another embodiment of the bolt. 
         FIGS. 5A to 5C , respectively, show top, side, and bottom views of a further embodiment of the bolt. 
         FIGS. 6A to 6C , respectively, show top and two side views of yet another embodiment of the bolt. 
         FIGS. 7A and 7B , respectively, show side views of still another embodiment of the bolt. 
         FIG. 8  shows a perspective view of another embodiment of the bolt. 
         FIG. 9  shows a perspective view of an embodiment of the solar panel clamping system. 
     
    
    
     DETAILED DESCRIPTION OF EXEMPLARY EMBODIMENTS 
     The following description of the illustrative, non-limiting embodiments discloses specific dimensions, configurations, components, and processes. However, the embodiments are merely examples of the present invention, and thus, the specific features described below are merely used to more easily describe such embodiments and to provide an overall understanding of the present invention. Accordingly, one skilled in the art will readily recognize that the present invention is not limited to the specific embodiments described below. Furthermore, the descriptions of various dimensions, configurations, components, and processes of the embodiments that would have been known to one skilled in the art are omitted for the sake of clarity and brevity. 
       FIG. 1  shows one embodiment of a fastener (e.g., a bolt)  10  that has a head  20  with an elastomeric element  30 . The head  20  of the bolt  10  is located on top of an elongated fastener  40  that engages another device (e.g., a nut) to perform a fastening operation. In  FIG. 1 , the fastener  40  is threaded to accept the nut so that twisting the nut in a certain direction (e.g., a clockwise direction) moves the nut from a distal end of the fastener  40  towards the head  20 . 
     As described in the more detailed examples below, when the elastomeric element  30  is compressed against a surface of a support structure, friction is created between the element  30  and the surface due to, in part, the resiliency of the element  30 . The compressed elastomeric element  30  may also urge the head  20  of the bolt  10  against one or more other surfaces of the support structure to increase the friction. As a result of the friction, the bolt  10  may be securely held in position during an installation or assembly process. Also, the friction may prevent the bolt  10  from turning and loosening after assembly to keep the assembly more structurally secure. 
       FIG. 2  shows an example of a top mounting clamping system that is used to position and hold a panel  45  firmly against a support structure  50 . As shown in the embodiment, the support structure  50  includes a space  65  adapted to accept the head  20  of the bolt  10  and hold the bolt  10  in an inverted position. The support structure  50  includes an upper portion  70  and a lower portion  80  that hold the head  20  of the bolt  10  within the space  65  between the portions  70  and  80 , and the fastener  40  of the bolt  10  projects from the support structure  50  through an opening (e.g., slot  60 ) in the upper portion  70 . After placing a panel  45  on the support structure  50  such that the fastener  40  projects through a hole in the panel  45 , a nut (not shown) may be tightened around fastener  40  of the bolt  10  and secure the panel  45  onto the support structure  50 . 
     When the head  20  of the bolt  10  is located in the space  65 , it contacts the upper portion  70  of the structure  50 , and the elastomeric element  30  contacts the lower portion  80  of the structure  50 . Since the elastomeric element  30  is compressed in the space  65 , it exerts pressure against the lower portion  80  and pushes the head  20  against the upper portion  70 . As such, there is friction between (1) the head  20  and the element  30  and (2) the support structure  50 , which prevents the bolt  10  from rotating within the structure  50  and loosening the connection between the panel  45  and the structure  50 . 
       FIG. 9  shows an example of a solar panel clamping system that uses the bolt  10  described above. In the system, the bolt  10  secures a solar panel  120  onto a support structure  50  (e.g., a solarmount rail  130 ). The rail  130  is elongated and has upper opposing jaws  170 , which form an upper portion  70  and a lower portion  80  that form the contours of a slot  60 . Also, as described above, a space  65  is formed between the upper and lower portions  70  and  80 . 
     To secure the panel  120  to the rail  130 , the bolt  10  is inverted, the head  20  of the bolt  10  is inserted in the space  65 , and the fastener  40  protrudes through the slot  60 . Specifically, the bolt  10  is positioned in the rail  130  by inserting the head  20  at the end of the rail  130  and sliding the bolt  10  along the slot  60  of the rail  130  to the desired position while the head  20  is in the space  65 . Since the compressed element  30  creates friction between the bolt  10  and the rail  130 , the bolt  10  remains in the desired position during the installation process, even prior to securing the panel  120  to the assembly. 
     After inserting the bolt  10  into the space  65  and moving it to the desired position, an end clamp  140  or a mid-point clamp  150  may be placed on top of the bolt  10  so that at least one portion of the clamp  140  or  150  covers the solar panel  120 . This clamp system may be made from aluminum, or from other metallic or non metallic materials. A flange nut  160  may engage the bolt  10  and secure the solar panel  120  to the solarmount rail  130  via the clamp  140  or  150 . Also, the clamp  140  or  150  may be omitted from the system, and the bolt  10  and nut  160  may directly secure the solar panel  120  to the rail  130 . Of course, the system is not limited to securing solar panels  120  to rails  130  and other types of panels or devices may be secured to other types of rails or support surfaces. 
       FIGS. 3A to 3C  provide different views of the bolt  10  shown in  FIG. 1 . In a non-limiting example, the head  20  of the bolt  10  has a maximum width that is larger than the width of the elongated fastener  40 . As shown, the head  20  has a generally rectangular shape in which two opposite angles are rounded. In other embodiments, the head  20  can be shaped like a square, rectangle, circle, ellipse, octagon, a parallelogram, or any other shape that provides for a width larger than the width of the elongated fastener  40 . Furthermore, while the head  20  in  FIGS. 3A to 3C  has a flat upper portion, it may also have a dome shape or another appropriate shape depending on the environment in which the bolt  10  is used. The size of the head  20  is sufficient to insert it and the elastomeric element  30  in its compressed form in the space  65  between the upper and lower portion  70  and  80  of the support structure  50 . 
     Also, in the embodiment illustrated in  FIGS. 4A to 4D , the elastomeric element  30  is separate from the head  20 . As such, the head  20  has an indented surface, groove or hole  25 , which accepts the elastomeric element  30 . 
       FIG. 4A  is a side view of one example of the bolt  10  in which the shorter width of the generally rectangular head  20  is shown in relation to the width of the fastener  40 . In the embodiment, the shorter width of the head  20  is substantially identical to the width of the fastener  40 .  FIG. 4B  is another view which shows the longer width of the head  20  in relation to the width of the fastener  40 . As illustrated, this width is larger than the width of the fastener  40 . 
     As discussed above, the elongated fastener  40  extends from the head  20  to engage a nut.  FIGS. 3A and 4D  show that the elongated fastener  40  has a generally cylindrical shape and contains threads along the outer surface of the cylindrical shape to engage a nut. In other embodiments, the elongated fastener  40  may have different shapes to operate with locking mechanisms other than a nut. While the size and shape of the elongated fastener  40  may depend on the size and shape of the panel or other item to be secured or the application in which the bolt is used, in one example, the elongated fastener  40  may have a length of about 1 inch to about 3 inches and a width ⅛ inch to about 1 inch. When threaded, the elongated fastener  40  optionally includes a “non-threaded” shoulder  90  above the threads as best shown in  FIGS. 3B ,  4 A, and  4 B. 
     Depending on the embodiment and the implementation, the elongated fastener  40  and the head  20  may be made from metallic or non-metallic material. In one example, the head  20  and the elongated fastener  40  are made from stainless steel. 
     In one implementation, the elastomeric element  30  compresses when the bolt  10 , for example, is inserted between the upper and lower portion  70  and  80  of a support structure  50 . As noted above, when the elastomeric element  30  is compressed, it pushes the head  20  against the upper portion  70  of the support structure  50  and, due to its resiliency, directly presses against the lower portion  80  of the support structure  50 . In one example, the elastomeric element  30  is made of rubber, but in other embodiments, it may be made of other materials. For instance, it could be made from various thermoplastics which exhibit a rubber-like behavior, like Santoprene™. 
     In some embodiments, the elastomeric element  30  holds the position of the bolt  10  relative to the support structure  50  due to the frictional force between the compressed elastomeric element  30  and the lower portion  80 . For example, after the head  20  of the bolt  10  is inserted in the space  65 , the elastomeric element  30  expands and exerts pressure on the head  20  of the bolt  10  and pushes it against the opposite side of the space  65  to provide sufficient friction to prevent the head  20  (and thus the bolt  10 ) from falling out of the space  65 . In one implementation, an elastomeric element  30  having a coefficient of friction of at least about 1 (and preferably between about 1 to about 4) in its uncompressed form can create sufficient friction to prevent the bolt  10  from falling out of the space  65 . 
     In one example, the size of the elastomeric element  30  should be large enough so that it is compressed when the head  20  of the bolt  10  is inserted between the upper and lower portions  70  and  80  of the support structure  50 . In this instance, the height of the elastomeric element  30  should be sufficient to push the head  20 , with enough force, against the upper portion  70  of the support structure  50  and to exert enough pressure on the lower portion  80  of the structure  50 . Depending on the size of the space  65 , such a height may be about 0.1 inch to about 0.4 inches. Also, the element  30  may take various shapes, such as a cylinder, a box, a pyramid, cone, a truncated pyramid, or a truncated cone. The examples in  FIGS. 3A to 4D  and other figures show that the elastomeric element  30  has a generally cylindrical shape in which the longitudinal axis of the element  30  aligns with the longitudinal axis of the cylindrical fastener  40 . However, the element  30  clearly is not limited to such a shape and orientation, and after reading the present specification, one skilled in the art would know how to adjust the size, shape, and orientation of the element  30  in light of the particular application. 
     As shown in  FIGS. 3A ,  4 A, and  4 B, the bolt  10  may include a dog point  100 . The dog point  100  is an unthreaded elongated tip that has a width less than the diameter of fastener  40 . The dog-point  100  aligns and positions, for example, a nut with respect to the threads of the fastener  40  allowing the installer to place the nut on the bolt  10  before the nut initially engages the threads of fastener  40 . In one implementation, the dog-point  100  is made from metallic or non-metallic material, such as stainless steel. In a further example, the dog point  100  may include a chamfer  110  to connect the dog point  100  to the fastener  40 , and the chamfer  110  may be angled at about 45° to allow an easy transition for the nut onto the threaded portion of the fastener  40 . 
     In other embodiments, the bolt  10  also includes one or more devices for preventing the bolt  10  from turning in a direction (e.g., counter-clockwise) in which it loosens its connection with the nut. For example, as shown in  FIGS. 4A and 4B , the bolt  10  may include nibs  35  to prevent it from turning counter-clockwise. The nibs  35  may be provided on the surface of the head  20  opposite to the surface on which the elastomeric element  30  is present. Although  FIGS. 4A and 4B  show the nibs  35  at the circumferential end of head  20 , other embodiments of the bolt  10  may have the nibs  35  off-set towards the center of the bolt  10 . Moreover, the nibs  35  may additionally or alternatively be placed on the surface of the head  20  where element  30  is present or on the side surfaces of the head  20 . In some of the embodiments that include nibs  35 , the elongated fastener  40  may include threads that would tighten the bolt  10  when turned in a clockwise direction. 
     Table 1 below includes examples of specific dimensions of the embodiments of the bolts  10  illustrated in  FIGS. 3A to 4D . 
     
       
         
           
               
               
               
             
               
                   
                 TABLE 1 
               
               
                   
                   
               
               
                   
                 FIG. 3 
                 Dimension 
               
               
                   
                   
               
             
            
               
                   
                 Length of head 20 
                 about 0.435 inches 
               
               
                   
                 Width of head 20 
                 about 0.25 inches 
               
               
                   
                 Length of fastener 40 (including shoulder 
                 about 2 inches 
               
               
                   
                 90 and dog point 100) 
               
               
                   
                 Length of dog point 100 
                 about 0.186 inches 
               
               
                   
                 Length of threaded portion of fastener 40 
                 about 1.590 inches 
               
               
                   
                 Height of head 20 
                 about 0.165 inches 
               
               
                   
                 Height of exposed portion of elastomeric 
                 about 0.125 inches 
               
               
                   
                 element 30 
               
               
                   
                   
               
            
           
         
       
     
       FIGS. 5A to 5C  shows another embodiment of the bolt  10  in which the head  20  also possesses the generally rectangular shape with rounded opposing angles. The bolt  10  in this example does not include a dog-point  110 . Table 2 below includes examples of specific dimensions of the bolt  10  illustrated in  FIGS. 5A to 5C . 
     
       
         
           
               
               
               
             
               
                   
                 TABLE 2 
               
               
                   
                   
               
               
                   
                 FIG. 5 
                 Dimension 
               
               
                   
                   
               
             
            
               
                   
                 Length of head 20 
                 about 0.435 inches 
               
               
                   
                 Width of head 20 
                 about 0.25 inches 
               
               
                   
                 Height of head 20 
                 about 0.165 inches 
               
               
                   
                 Length of fastener 40 
                 about 1.125 inches 
               
               
                   
                 Length of dog point 100 
                 about 0.186 inches 
               
               
                   
                 Height of exposed portion of elastomeric 
                 about 0.125 inches 
               
               
                   
                 element 30 
               
               
                   
                   
               
            
           
         
       
     
       FIGS. 6A to 6C  illustrate yet a further embodiment of the bolt  10  in which the head  20  has a shape of a parallelogram and in which the elastomeric element  30  has the shape of a truncated cone. As shown in  FIGS. 6B to 6C , the fastener  40  of the bolt  10  is threaded up to the head.  FIGS. 7A and 7B  show another example of the bolt  10  having a “non-threaded” shoulder  90  above the threaded portion of the fastener  40 . Table 3 below includes examples of specific dimensions of the bolts  10  illustrated in  FIGS. 6A to 7B . 
     
       
         
           
               
               
               
             
               
                   
                 TABLE 3 
               
               
                   
                   
               
               
                   
                 FIG. 6 
                 Dimension 
               
               
                   
                   
               
             
            
               
                   
                 Length of one side of head 20 
                 about 0.503 inches 
               
               
                   
                 Width of head 20 
                 about 0.25 inches 
               
               
                   
                 Length of fastener 40 (including shoulder 
                 about 2 inches 
               
               
                   
                 90 and dog point 100) 
               
               
                   
                 Diameter of dog point 100 
                 about 0.186 inches 
               
               
                   
                 Length of dog point 100 
                 about 0.186 inches 
               
               
                   
                 Length of threaded portion of fastener 40 
                 about 1.590 inches 
               
               
                   
                 Height of head 20 
                 about 0.165 inches 
               
               
                   
                 Height of exposed portion of elastomeric 
                 about 0.125 inches 
               
               
                   
                 element 30 
               
               
                   
                 Diameter of elastomeric element 30 at its 
                 about 0.197 inches 
               
               
                   
                 base 
               
               
                   
                 Diameter of elastomeric element at its 
                 about 0.118 inches 
               
               
                   
                 upper portion 
               
               
                   
                 Degree of chamfer 110 
                 45° 
               
               
                   
                   
               
            
           
         
       
     
       FIG. 8  shows another embodiment of the bolt  10 . In this example, the elastomeric element  30  comprises a spring that presses the head  20  against the upper portion  70  of a support structure  50  and that presses against a lower portion  80  of the support structure  50 , as described above. 
     While the various embodiments above contain different components and features, upon reading the specification, one skilled in the art readily will realize that such components and features in one embodiment may be incorporated into or combined with components and features of another embodiment. Also, the previous description of the embodiments is provided to enable a person skilled in the art to make and use the present invention. Moreover, various modifications to these embodiments will be readily apparent to those skilled in the art, and the generic principles and specific examples defined herein may be applied to other embodiments without the use of inventive faculty. Therefore, the present invention is not intended to be limited to the embodiments described herein but is to be accorded the widest scope as defined by the limitations of the claims and equivalents thereof.