Patent Abstract:
A boat latch for securing a boat or the like having a bow ring to a trailer including,
   a roller mount assembly having a roller adapted to guide the bow of a boat into position said roller being attached to an upper end of a kicker arm, said kicker arm being pivotally mounted in a housing;   a locking pin assembly movable between a cocked and a free position;   whereby as a boat is guided into position against the roller mount assembly a rotation of said kicker arm may be induced by pressure exerted against the roller by a boat to thereby activate the locking pin at a position wherein the locking pin engages the bow ring to thereby secure the boat to the trailer.

Full Description:
FIELD OF THE INVENTION 
       [0001]    The present invention relates to a boat latch. The latch of the present invention is of assistance in the retrieval of boats onto a trailer. 
       BACKGROUND OF THE INVENTION 
       [0002]    Boats carried on trailers are used for both recreational and commercial purposes in significant numbers. Typically boats would be launched from and retrieved from an inclined boat-launching ramp or similar. The boat is secured to the trailer by a latch attaching to the bow of the boat. The boat is released by lowering the boat and trailer into the water to a sufficient depth to allow the boat to float and then releasing the latch. The procedure is reversed when the boat is retrieved: thus, the boat is manoeuvred onto the trailer and then secured by the latch. 
         [0003]    The operation is not always easily achieved and, recovery of the boat from the water onto the trailer, in particular, can be difficult to achieve. The present invention offers an alternative to existing boat trailer latches. The boat trailer latch of the invention is particularly suited to new skid bed/roller bed trailer design, which allows the boat to be driven up on to the trailer to its resting position. 
       SUMMARY OF THE INVENTION 
       [0004]    Therefore according to a first aspect of the present invention there is provided a boat latch for securing a boat or the like having a bow ring to a trailer including,
       a roller mount assembly having a roller adapted to guide the bow of a boat into position said roller being attached to an upper end of a kicker arm, said kicker arm being pivotally mounted in a housing;   a locking pin assembly movable between a cocked and a free position;   whereby as a boat is guided into position against the roller mount assembly a rotation of said kicker arm may be induced by pressure exerted against the roller by a boat to thereby activate the locking pin at a position wherein the locking pin engages the bow ring to thereby secure the boat to the trailer.       
 
         [0008]    Preferably, the kicker arm is biased into a disengaged position. More preferably, the kicker arm is biased into position by a compression spring acting against a rear upper side of the kicker arm. 
         [0009]    Preferably, the locking pin is biased into an engaged position and may be secured in the cocked position against a stop 
     
    
     
       DESCRIPTION OF DRAWINGS 
         [0010]    The above and other objects, features, and advantages of the present invention will be apparent from the following detailed description of a preferred embodiment in conjunction with the accompanying drawings. In the drawings: 
           [0011]      FIG. 1  shows a boat located on a boat trailer incorporating a latch in accordance with the present invention; 
           [0012]      FIG. 2  illustrates in cross-sectional side view the latch of the present invention in a detached position; 
           [0013]      FIG. 3  illustrates in cross-sectional side view the latch of the present invention in an attached position; 
           [0014]      FIG. 4  represents in a first perspective view the latch of the present invention removed from a trailer as viewed from below; 
           [0015]      FIG. 5  represents in a second perspective view the latch of the present invention removed from a trailer as viewed from above; and 
           [0016]      FIG. 6  shows an alternate side view of the latch showing a boat secured by a locking pin; and 
           [0017]      FIG. 7  illustrates in schematic side view an alternative embodiment of the present invention. 
       
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0018]    The following detailed description of the invention refers to the accompanying drawings. Although the description includes exemplary embodiments, other embodiments are possible, and changes may be made to the embodiments described without departing from the spirit and scope of the invention. Wherever possible, the same reference numbers will be used throughout the drawings and the following description to refer to the same and like parts. 
         [0019]    Shown in  FIG. 1  is a boat trailer latch  10  in accordance with a first aspect of the present invention. The latch  10  is attached to, and forms a part of a conventional boat trailer  12 . A boat  14  is shown in the secured position in the drawing. 
         [0020]    The boat latch  10  can be seen in greater detail in  FIGS. 2-5 . 
         [0021]    The latch  10  includes a mounting roller  16  located in a roller-mount assembly  18 . As can be seen from the drawings the mounting roller  16  is held generally horizontally in use and is adapted to contact the bow of the boat  14  during retrieval. The mounting roller  16  is freely rotatable about a horizontal axis. The roller mount assembly  18  serves to hold the roller  16  in position and consists of a pair of side arms  22  attached to the roller at ends thereof through an axis  24  of the roller  16 , each of the side arms  22  projecting from a base member  26  to thereby complete the roller-mount assembly  18 . The roller  16  is of a type conventionally used in boat trailers and is manufactured of nylon or other suitable material. 
         [0022]    Extending generally downwardly from the base member  26  is a kicker arm  28 . The kicker arm  28  is seen to advantage in  FIGS. 2 and 3 . The kicker arm  28  consists of a flat plate having a generally central transverse pivot point  30 . The pivot  30  is, in turn, secured in within and against the walls of a channel member  32 . The channel member  32  is approximately L shaped having a longer limb  34  and a shorter limb  36 . The longer limb  34  is attached, through a mounting plate  37 , to an upright  38  extending from the boat trailer  12 . The shorter  36  limb of the channel member  32  is open-ended to allow the kicker arm  28  to extend upwardly through the open end to the base member  26 . 
         [0023]    It can be seen from the drawings that the kicker arm  28  occupies most of the length of the shorter limb  36 . As has been noted the kicker arm  28  is secured to the channel  32  by a pivot point  30 . The kicker arm  28  is generally freely rotatable about the pivot  30  within the confines of the channel member  32 . Nylon bushes and washers and a split pin are used to secure this arrangement and facilitate the free movement of the kicker arm  28 . 
         [0024]    The kicker arm  28  is, however subject to influences beyond the mere shape of the channel  32 . 
         [0025]    An uppermost part of the kicker arm  28  has a rearmost projecting tang  40 . The tang  40  is received in a cylindrical housing  42  positioned on an inner wall of the located within the shorter limb  36  of the channel member  32 . The housing  42  also serves to hold a kicker arm compression spring  44 . The outer edge of the kicker arm  28  is profiled and cut so as to allow a close fit between the kicker arm  28  and the housing  42 . The kicker arm compression spring  44  acts on the upper end of the kicker arm  28  to bias the kicker arm into a resting position. 
         [0026]    Thus, in the orientation shown in the drawings the kicker arm  28  is biased by the compression spring  44  so that it maintains an upright position, and more specifically, the kicker arm  28  is biased in a clockwise direction. However, the kicker arm is attached at its upper end the roller  16 . Force acting on the roller  16  is therefore able to counteract the effect of the compression spring  44  as indicated in  FIG. 2 . 
         [0027]    At a lowermost end of the kicker arm  28  there is a lower tang  46  that is forwardly projecting. An aperture  49  is cut into the channel member  32  to allow the tang  46  to extend therethrough. Counter clockwise rotation of the kicker arm  28  about the pivot point  30  allows the tang  46  to contact a locking pin  48 . As will be described the movement of the locking pin  48  activates the locking mechanism. 
         [0028]    The locking pin mechanism is positioned forwardly of the kicker arm  28  and is, in use, closer to the boat  14 . A pair of parallel, outermost forwardly extending flanges  50  is attached one to each side of the shorter limb of the channel member  32 . The flanges  50  can be seen most clearly in  FIG. 4 . 
         [0029]    The flanges  50  terminate in outwardly directed guide wings  52 . The guide wings  52  serve to avoid damage to the boat as the boat  14  is guided onto the trailer  12 . The guide wings  52  are covered in a nylon material. The guide wings  52 , in use, rest below the roller  16  and act in concert with the roller  16  to position the boat during retrieval. 
         [0030]    The locking pin  48  is a U shaped member that passes through, and is secured in, the flanges  50  and then turns through 180° to pass below the flanges  50 . The locking pin  48  also passes through a barrel  54  positioned adjacent a flange  50 . Within the barrel  54  is a locking pin spring and associated washer. The locking pin spring ensures that the locking pin  48  is maintained in position with the lower arm passing below the guide wings  52  and flanges  50 . By pulling on the locking pin  48  it is possible to act against the locking pin spring and to withdraw the locking pin  48 . 
         [0031]    The locking pin  48  can be withdrawn against the action of the locking pin spring to a cocked position. The locking pin  48  is maintained in this position by the lower arm of the U-shape bearing against a locking pin stop plate  56  attached to an outer surface of the channel member  32 . 
         [0032]    As the boat  14  is driven forward on to the trailer  12  the guide wings  52  locate the D-shackle or U-bolt on the bow of the boat to its final resting position. The bow of the boat  14  then encounters the roller  16 , which then rotates on its horizontal axis  24 . At the same time the movement of the boat against the roller  16  exerts a pressure thereon that results in a rotation of the roller  16  backwards, that is in a counter clockwise direction as viewed from  FIG. 2  around the pivot point  30  and against the action of the compression spring  44 . This of course rotates the whole of the kicker arm  28  and the lowermost point of the kicker arm  28  and the tang  46  are also rotated counter clockwise and the tang  46  emerges through the aperture  48  to strike the lower arm of the locking pin  48 . The locking pin  48  is thereby moved forwardly and released from the locking pin stop plate  56 . The spring in the barrel  54  shoots the locking pint  48  across the bow of the boat passing through the locking pin  48  through the D-shackle or U-bolt on the bow of the boat thereby securing the boat to the trailer. 
         [0033]    Thus then, as the boat is driven, winched or otherwise hauled onto the trailer the operator is in a position to monitor the gradual movement of the boat and, at a point when the locating the D-shackle or U-bolt on the bow of the boat in line with the desired resting position. On the trailer, the action of the boat moving against the roller  16  activates the locking pin  48  out of the cocked position, that is, engagement with the stop plate  56  and the locking pin moves to collect the boat through the shackle. 
         [0034]    To facilitate this process the end of the locking pin that passes through the shackle on the boat is tapered to allow easy entry through the shackle. Once the boat has been secured an R clip  58  can be used to lock the locking pin  48  against inadvertent release. In addition, a washer  60  is fixed to the rear side of the locking pin  48  to thereby prevent excess travel of the pin. 
         [0035]    The latch  10  of the invention may incorporate additional features including a safety catch  62  that loops over the lower arm of the locking pin  48  an prevents inadvertent firing of the pin. 
         [0036]    Shown in  FIG. 7  is an alternative form of the present invention. The boat latch  100  shown in  FIG. 7  is in many respects similar to the latch  10  shown in  FIGS. 1-6  and like numerals have been used to indicate like parts. 
         [0037]    In the latch  100 , the roller mount assembly  18  is attached to the channel member  32  through adjustable side flanges  61 . The side flanges  61  are attached to a winch plate  64  and are pivotally movable about a pivot pin  63  located at the end of the winch plate  64 . The winch plate  64  is welded to the mounting plate  37  and is further supported in position by means of support  65 . The degree of movement of the adjustable side flanges  61  is constrained by arcuate slots that receive pins  66 . 
         [0038]    The relative angle at which the roller mount assembly  18  is presented to a boat hull is variable thereby allowing the latch  100  to be used with a variety of boat hull angles. 
         [0039]    Further advantages and improvements may be made to the present invention without deviating from its scope. In particular the angle and position at which the latch assembly is mounted and the dimensions of the channel member are able to varies to accommodate differing boat geometries. Thus, although the invention has been shown and described in what is conceived to be the most practical and preferred embodiment, it is recognized that departures may be made therefrom within the scope and spirit of the invention, which is not to be limited to the details disclosed herein but is to be accorded the full scope of the claims so as to embrace any and all equivalent devices and apparatus. 
         [0040]    In any claims that follow and in the summary of the invention, except where the context requires otherwise due to express language or necessary implication, the word “comprising” is used in the sense of “including”, i.e. the features specified may be associated with further features in various embodiments of the invention.

Technology Classification (CPC): 1