Abstract:
This invention relates to a hinge for interconnecting sections of a floating dock and for interconnecting walkways with floating docks. This hinge protects docks from being damaged by stress exerted by the side to side or up and down motion of the wave, storm or high winds. This hinge can also be used for reconstructing old damaged docks. The hinge comprises two stackable sheet of twisting members which are preferably flat, each having an arcuate front end for facilitating a twisting motion of the twisting members relative to each other, a mounting plate, and a central opening for accomodating a pivot rod; a fastener for keeping the hinge components together; and, preferably washers to protect the outside surfaces of the twisting members from abrasion. One side of the hinge preferably attaches to a dock section having a dock joint bracket while the other end preferably attaches to a plain corner bracket to allow vertical pivotal movement of the dock sections in response to wave motions. A cover is provided if a gap is formed by the space occupied by the hinge.

Description:
BACKGROUND 
   This invention relates to a hinge for interconnecting sections of a floating dock and for interconnecting walkways with floating docks. This hinge can be used both for reconstructing docks which have been damaged by storm or high winds or for constructing new docks that can better withstand the stress exerted by the side to side or up and down motion of the dock. 
   Most docks have sections interconnected together by simply threading a suitably diametered rod through a pair or a series of sturdy eye bolts secured in an aligned relation to the adjoining opposed vertical faces of the dock sections or through aligned bearing openings in pairs of metal bearing plates secured to the vertical sides of the respective adjoining dock sections and projecting downwardly therefrom. These eyebolts are usually constructed on corner brackets installed at each corner of the interconnecting dock sections but more aligned eyebolts may be installed along the vertical sides of the dock sections if reinforcement is desired or necessary, for example, when the dock sections span a sizeable width. The vertical faces of the interconnecting dock sections are positioned face to face and end to end in spaced apart relation relative to one another. These types of interconnection is usually restrictive of dock movements in relation to wave actions, high winds, or heavy loads thereby resulting in structural damage to the dock after some time of usage. Reconstructing damaged docks is costly since it requires downtime, materials and labor before it again becomes operational. 
   This problem has been addressed by installing flexible materials covering the gap between the interconnected clock sections to allow the sections to move with respect to each other or by installing semi-flexible hinges to each adjacent dock faces. These flexible materials, usually rubber based, are however not long lasting and while they may address the up and down motion of the dock, they are not very efficient in dealing with damages caused by the side to side motion of the clock. 
   It is therefore and object of this invention to provide a dock hinge that will allow the interconnecting dock sections to move side to side and up and down relative to each other. 
   It is also an object of this invention to provide a hinge that is simple and easy to install. 
   It is a further object of this invention to provide a hinge that can be easily installed on old damaged docks or to replace existing hinges on functional docks to preserve the docks from damage. 

   
     BRIEF DESCRIPTION OF THE DRAWING 
       FIG. 1  is a perspective view of the hinge connecting two dock sections. 
       FIG. 1A  is a blow up of the dock joint bracket connected to a dock section. 
       FIG. 2  is a side view of the assembled hinge connected to the dock sections including the plywood covering the gap sections above the hinge. 
       FIG. 3  is an exploded view of how the components of the hinge are assembled together. 
       FIG. 3A  is an exploded view of a grease zerk attaching to a bolt head or washer. 
       FIG. 4  is a perspective view of the cover laid on top of the decking to cover the gap formed by the installation of the hinge. 
   

   SUMMARY 
   This invention relates to a hinge for interconnecting sections of a dock or for interconnecting walkways to a dock. The hinge comprises two stackable sheet of twisting members which are preferably flat, each having an arcuate front end for facilitating a twisting motion of the twisting members relative to each other, a mounting plate, and a central opening for accomodating a pivot rod; a fastener for keeping the hinge components together; and, preferably washers to protect the outside surfaces of the twisting members from abrasion. One side of the hinge preferably attaches to a dock section having a dock joint bracket while the other end preferably attaches to a plain corner bracket to allow vertical pivotal movement of the dock sections in response to wave motions. A cover is provided for a gap formed by the space occupied by the hinge. This cover is typically made of wood such as marine plywood laid on top of the interconnecting dock sections having an unbolted beveled arched edge on one end and a bolted beveled horizontal edge on the other end, the beveled edges extending beyond the interconnected vertical faces of the dock sections and lateral side ends coterminally aligning with the lateral side ends of the dock sections. 
   The hinge connects two dock sections or a walkway to a dock positioned face to face and end to end by the following steps: a) stacking an upper and a lower twisting member, each having a flat frame, a central hole, and a mounting plate in an orientation wherein the mounting plate of the upper twisting member face away from the mounting plate of the lower twisting member; b) aligning the central hole of the upper and lower twisting members; c) introducing a pivot rod through the aligned central holes; d) fastening the stacked twisting members together thereby forming an assembled hinge; and, e) mounting the assembled hinge by connecting/attaching the mounting plates to corresponding brackets on corresponding vertical faces of the dock sections or walkway. To further increase the lifetime of the hinge by preventing damages caused by abrasion, the following steps are added: between step b) and c), placing a washer having a center hole on top of the upper twisting member in such a way that the center hole aligns with the central holes of the twisting members; between d) and e) placing a washer having a center hole on the bottom of the lower twisting member in such a way that the center hole aligns with the central holes of the twisting members; and, greasing outside surfaces of a component of the hinge that comes in contact with outside surfaces of another component of the hinge. If a gap is formed between the interconnected dock sections due to the space occupied by the hinge, a covering, preferably a marine plywood, is laid over the gap to avoid injuries to dock users. 
   DETAILED DESCRIPTION OF THE INVENTION 
   Floating docks are typically constructed from pivotally interconnected dock sections positioned face to face and end to end in spaced apart relation to each other. The dock sections typically include a rectangular frame having a flat top decking formed from a plurality of deck boards secured to the top of the frame. Other docks however may be of another shape other than rectangular. The length of the deck boards typically matches the width of the frame so as to be coterminus. The hinge to pivotally interconnect one dock section to another is usually secured on a vertical face of one frame facing a corresponding vertical face of another frame as shown in  FIGS. 1 and 2 . Docks and dock sections come in different dimensions and the hinge proposed herein is applicable to all sizes. The dock may be constructed of concrete, wood, metal or plastic. The dock sections are usually constructed at even width increments, such as 2 ft., 3 ft., 4 ft., 5 ft., 6 ft. and so on.  FIG. 1  shows the hinge  1  of the invention interconnecting two dock sections  2  and  3 .  FIGS. 2 and 3  shows the parts making up the hinge  1 ,  2  pieces of corresponding twisting members, an upper twisting member  4   a  and a lower twisting member  4   b  which are two preferably stackable flat sheets of material having an arcuate front, a horizontal base and a central opening, a pivot rod  5  which herein is exemplified by a bolt, a fastener  6  which is a nut if a bolt is used as the pivot rod and preferably two washers  7   a  and  7   b  for protecting the twisting members from rubbing on the surface of the fastener  6 . As stated above, the size of the hinge  1  depend upon the width of the deck section to which the hinge will be attached. For example, for dock sections each with a length of 200 ft. and a vertical face  8  of 6 ft., for hingedly connecting together the dock sections in opposed parallel orientation, a ⅜ inch thick of twisting members  4   a  and  4   b , ⅜ inch thick×14 inch diameter washers  7   a  and  7   b , 4 inch diameter bolt  5  and 4 inch diameter nut  6  are suitable for use. The nut is typically locked on a side opening by a set screw. The hinge is preferably made of hot dipped galvanized hot roll iron for strength and longevity. Other materials are suitable as long as they are corrosion resistant and possess the same properties as that found in galvanized iron or galvanized steel. 
   The proposed hinge  1  may be installed in any type of dock. A detailed description of the construction of a dock or more specifically, a floating dock is known and is deemed unnecessary. The bolt  5 , nut  6 , and washers  7   a  and  7   b  used in constructing the hinge herein are conventional and commercially available, however, parts of comparable functions may be customized. The twisting members  4   a  and  4   b  and the mariner of attachments to the dock sections differentiate this hinge from conventional hinges. To allow the hinge to move up and down according with the motion of the wave and side to side with the force of the strong wind and protect the dock from breaking, it is preferably designed with two identical stackable twisting members  4   a  and  4   b  which is constructed with a flat frame  9  having an arcuate front  10  elevated by vertical sides  11   a  and  11   b  which are both in turn extended diagonally at each end by sides  12   a  and  12   b , terminating at each end with mounting plates  13   a  and  13   b . The base  15  opposite the arcuate front  10  of the frame is horizontal. The mounting plates  13   a  and  13   b  are positioned perpendicular to the flat frame  9  of the twisting members  4   a  and  4   b . These mounting plates are typically welded to the twisting members. Although the figures show a preferred design for the hinge, alternate designs are possible so long as there are two stackable members that can twist from side to side relative to each other with an angular span of 30-40 degrees. Both twisting members  4   a  and  4   b  have a central hole  14  preferably located midway between the two mounting plates at each end of a twisting member and midway between the base  15  of the frame  9  and the arcuate front  10  of each twisting member. The central hole  14  of each twisting member align with each other when the twisting members are stacked or superimposed to each other. 
   The hinge is fully assembled before it is mounted to the opposed vertical faces  8  of the dock sections.  FIG. 3  shows how the components are assembled together. Before mounting the hinge  1 , the two twisting members  4   a  and  4   b  are placed on top of each other in an orientation that positions the mounting plates of  4   a  to face opposite or away from that of the mounting plates of  4   b  as shown in  FIGS. 1 and 3 . A washer  7   a  having a center hole  17  is preferably placed on top of the upper twisting member  4   a  in such a way that the center hole  17  aligns with the central hole  14 . A pivot rod  5  is then introduced through holes  17  and  14  to provide a pivot point and to keep the twisting members together prior to the hinge being fastened together. A second washer  7   b , having an identical center hole  17  as in washer  7   a , is preferably installed at the bottom surface  26  of the lower twisting member  4   b . A fastening device  6  to keep the hinge components stacked together, which in this example is a nut, is screwed on the bottom protruding threaded end  27  of the pivot rod  5  which in this example is a bolt. The receiving vertical faces  8  of the dock sections would typically have dock joint brackets  18  to which the mounting plates  13   a  and  13   b  would attach to as shown in  FIGS. 1 and 2 . These dock joint brackets are typically bolted to the vertical faces of the dock sections but other means of attachments known in the art may be used. There are several kinds of dock joint brackets that are available commercially. Any type that can accommodate the mounting plate can be used. The dock joint bracket  18  as shown in  FIG. 1A , preferably will have a female member  19  and a male member  20  on a corner bracket, the female and male member coupled by a connecting pin  21  having a locking hairpin  22  to secure the connecting pin in place. These types of brackets are preferred because the female member  19  and the male member  20  can pivot relative to each other around the connecting pin  21  thereby allowing the interconnected dock sections to undergo vertical pivotal motion in response to momentary wave motion. As shown in  FIG. 1 , one pair of mounting plates  13   a  and  13   b  from the upper twisting member  4   a  are connected to corresponding back surfaces  23  of female members  19  of a pair of dock joint brackets while the other pair of mounting plates  13   a ′ and  13   b ′ from the lower twisting member  4   b  are connected to a corner bracket  24  without a dock joint. The mounting plates typically have holes  25  corresponding to the holes  16  of the respective brackets through which bolts  32  or other connecting devices having a longitudinal body can go through. Depending upon the position of the float  28  relative to the dock, it may be necessary to temporarily slide the float out of the way before installing the hinge. 
   In the assembly of hinge  1 , grease is preferably applied to lessen or prevent abrasion that may be caused by friction between the rubbing contacting surfaces of the twisting members  4   a  and  4   b  or between the contacting surfaces of the washers, the fasteners and the twisting members. The washers are also preferably made of hot dipped galvanized hot roll iron. Grease zerks  33  as shown in  FIGS. 3 and 3A  are installed on the bolt and on the upper washer  7   a  and the lower washer  7   b  to allow periodic regreasing of the hinge preferably by use of a grease gun. The grease zerks installed on the bolt will allow grease to travel through the washers, as well, so long as there are holes in the washer corresponding to the holes of the bolt through which the grease goes through. Grease zerks are commercially available from hardware stores. 
   A gusset  29 , preferably triangular in shape, is recommended and this is welded at each end of the twisting members at a position midway between the edges of the mounting plates. The gusset  29  is oriented perpendicular to the mounting plate and protrudes upward as shown in  FIGS. 1 and 3 . The gusset strengthens the attachment of the mounting plate to the frame of the twisting member as well as the attachment of the mounting plate to the dock joint bracket or corner bracket. Like the other components of the hinge, the gusset is also preferably made of hot dipped galvanized hot roll iron. 
   Due to the weight of hinge  1 , it is preferable to install lifting brackets  34  on the bolt head  35  for easy transport. If a bolt is not used, the lifting brackets and the grease zerks above can be installed to the corresponding component used in lieu of the bolt. 
   When the hinge  1  is used to repair damaged docks instead of a new construction, it is simply mounted directly on the dock sections in the same manner as above. If there are existing brackets, one simply removes the old bolts on the existing brackets, move and align the corresponding holes  25  of the mounting plates to the existing holes of the bracket, and reinstall the old bolts through the mounting plate and bracket. For proper functioning, the hinge  1  should attach to one dock section having a dock joint bracket  18  and to the opposite dock section having a plain corner bracket  24 . 
   After the assembly of hinge  1 , depending upon the extention of the top decking  31  there may be a gap  30  formed between the dock sections  2  and  3 , corresponding to a space occupied by the hinge. To ensure that no dangerous openings or clefts are present between the dock sections where a hand or foot may be accidentally caught or pinched, thereby causing injury, the gap is covered typically with plywood, preferably a ¾ inch marine plywood which is shown in FIG.  4  and in dashed lines on FIG.  1 . Metal, plastic, and other types of wood that are heavy and can withstand repeated exposure to rain and strong wind are also suitable. The cover  36  is preferably laid on top of the top decking  31  of the interconnected dock sections as shown in  FIGS. 2 and 4 . To achieve the intended function of hinge  1 , the front and back ends of the plywood preferably extend beyond the junction where the hinge  1  connects with the vertical faces  8  of the dock sections while the lateral side ends coterminally align with the lateral side ends of the dock sections as shown in FIGS.  1 ,  2 ,  3  and  4 . The cover  36  is preferably shaped with an arched edge  37  on one end and a horizontal edge  38  on the other end. 
   The arched  37  and the horizontal  38  edges are beveled at approximately 15-30 degrees to prevent a user from tripping. The length of the beveled edges typically ranges from ¼ in. to 3 inches. The side of the cover with a horizontal edge  38  extends preferably by about  6  inches beyond the vertical face of the dock section and is bolted to the dock section as shown in FIG.  4 . The arched end, likewise, extend beyond the vertical face of the opposite dock section but is not bolted to allow the cover  36  to move with the movement of the dock sections. However, to ensure that every point of the cover  36  contacts the surface of the articulating dock, the top  39  of the arched edge  37  is approximately 18 inches beyond the vertical face of the dock section located on the same side as the arched edge. This amount of overlap and the weight of the cover prevent the arched end from lifting away from the top decking  31  even if this end is not bolted. Also, as seen in  FIG. 4 , the arching starts from the lateral sides and extends through the entire width of the top deck. 
   The description herein purposely do not specify the dimensions of the hinge and its components because these vary according to the size of the dock sections to be interconnected. The example given will teach those in the art on how to proportionally adjust the dimensions for the particular application. 
   While the embodiment of the present invention has been described, it should be understood that various changes, modifications and adaptations may be made therein without departing from the spirit of the invention and the scope of the appended claims. Those skilled in the art will recognize that other and further variations of the features presented herein are possible. The scope of the present invention should be determined by the teachings disclosed herein, the appended claims and their legal equivalents.