Abstract:
A boat centering device for a trailer, the device having a lever arm with a contact member mounted on one end and an outrigger mounted on the other, the lever arm adapted to rotate towards the center of the trailer when the contact member is contacted by a boat. The outrigger urges the boat to the center of the trailer and does not contact the boat once the boat is centered. Matched pairs of lever arms are attached at various points on the trailer to cooperate in centering the bow and stern of the boat.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    1. Field of the Invention 
         [0002]    The present invention pertains to trailers for boats and, more particularly, to a device for loading a boat on a boat trailer that automatically centers the boat on the trailer during the loading operation and is adaptable to existing trailers. 
         [0003]    2. Description of the Related Art 
         [0004]    Most recreational boats are stored and transported on a trailer that is towed by a personally owned vehicle. Proper positioning of the boat on the trailer is critical to the safe movement of the trailer on the highways. For example, positioning the boat too far to the rear of the trailer will cause the trailer to fishtail and it will raise the rear end of the tow vehicle, reducing traction from the tow vehicle wheels. Positioning the boat too far forward on the trailer will cause too much weight on the hitch, which will drag the rear of the tow vehicle down and make steering more difficult. 
         [0005]    Lateral positioning of the boat on the trailer is also critical, not only for safe transportation and launching and recovery, but also for protecting the hull of the boat. As shown in  FIG. 1 , most trailers  100  typically have a longitudinal center rail  102  on which are mounted keel rollers  104  for supporting the keel of a boat. The trailer  100  also includes side rails  106 , generally parallel to the center rail  102 . The side rails  106  typically have bunks  108  or rollers (not shown) or a combination of bunks  108  and rollers for cushioning and stabilizing the boat hull. The exact configuration of the trailer will depend on the type of boat hull. 
         [0006]    In some cases, an all-roller trailer is useful for boats having a center keel and left and right sponsons. Alignment of the sponsons with the cradle rollers on the side rails is important to properly support the boat and avoid damage to the hull. 
         [0007]    Loading a keel roller trailer requires some skill and agility. With the boat floating near a dock, the trailer is positioned in the water so that the boat and the trailer have their longitudinal axes in general alignment. A winch line is attached to the bow eye on the bow of the boat and the boat is winched onto the trailer with the rollers supporting most or the entire load of the boat. Ideally the boat will remain in alignment with the center rollers. However, wind and waves can cause a boat to easily move off the rollers, requiring quick continual action on the part of those loading the boat. Under less than ideal conditions, this will be a difficult task for an individual to perform alone. 
         [0008]    Recently, a new style of trailer has been designed that consists of only bunks and no rollers. In some of these designs, a single vestigial keel roller is located at the stern end of the trailer to deflect the boat upward onto the bunks when loading. Once the boat is fully winched onto the trailer, the stern of the boat no longer contacts the keel roller. Thus, the entire weight of the boat is supported on the bunks and not on the rollers. One disadvantage of this design is that the bunks provide little support for the transom area where the greatest weight of the boat is found, i.e., the engine and fuel. This can place a substantial amount of load on the hull of the boat, which functions as a cantilever to hold up the transom. Because the low-profile trailers are almost completely submerged, the boats are essentiality floated onto the trailer. There is little or no winching of the boat up the trailer because of the substantial friction that would result between the boat hull and the carpeted bunks. Lateral and longitudinal alignment of the boat on the trailer is sometimes more difficult with the float-on trailer design. 
         [0009]    Numerous designs have been proposed to assist in loading a boat onto a trailer so that the boat is centered with respect to the trailer, both longitudinally and laterally. For example, U.S. Pat. No. 3,077,277 describes a boat trailer that includes a central roller and a pair of outside rollers that are supported on angularly shaped members that are pivoted on pivot pins. Distal rollers are described as being held in a down position against the trailer by weight and are pushed into engagement with the boat hull as the boat keel bears down on a roller that joins two mutually-opposed arms. Because these arms are coupled together through the single roller, the keel of the boat must bear down on the central roller in order to activate the arms. Hitting only one of the arms will not cause either of the arms to move the hull to a centered position. 
         [0010]    In U.S. Pat. No. 4,138,135, a boat trailer is described having a wheeled frame with a tongue extending from a forward end thereof. A boat support is provided on the frame between the opposing sides for supporting the bottom portion of a boat. A pair of spaced-apart arms is pivotally secured to the frame at one side thereof and extends upwardly. A guide rail is secured to and extends between the upper ends of the pair of arms for engagement with one side of the boat. A spring is connected to each of the arms for yieldably urging the guide rail towards the center of the trailer and into engagement with the side of the boat. A second pair of arms is secured to the frame on the other side thereof and extends upwardly therefrom with a second guide rail secured to the upper ends thereof. Thus, the pair of arms in this design are pivotally mounted on the trailer frame and biased towards the center of the trailer by undercarriage springs at a free end of the arms. Hence, a boat loading onto this trailer will contact the arms along the side of the hull and scrape against the guide rails as the boat is being winched onto the trailer. In addition, the guide rails remain in contact with the boat as the boat is being transported, causing wear and chafing on the boat hull. 
         [0011]    Hence, there is a need for a mechanically-simple device that automatically centers a boat on a trailer without causing damage to the hull and that is easily adaptable to existing trailers. 
       BRIEF SUMMARY OF THE INVENTION 
       [0012]    A boat centering device and assembly are provided in the disclosed embodiments of the invention described herein. In one embodiment of the invention, a boat centering device for a trailer is provided. The device includes a lever arm having a first end and a second end, the lever arm adapted to be mounted on a mount on the trailer. Ideally, the lever arm rotates about an axis substantially parallel to the longitudinal axis of the trailer. A contact member is mounted on the first end of the lever arm and configured to be contacted by the boat, and an outrigger is mounted on the second end of the lever arm, the outrigger adapted to urge the boat towards the longitudinal axis of the trailer when the contact member is in contact with the boat and to not contact the boat when the boat is centered on the trailer. Ideally, a biasing member is adapted to rotate the lever arm in a direction that will move the contact member upward when the contact member is not in contact with the boat hull. In accordance with an aspect of the forgoing embodiment, the biasing member includes a torsion spring. 
         [0013]    In accordance with a further aspect of the forgoing embodiment, the contact member includes a support post having a first end adapted for attachment to the first end of the lever arm and a second end adapted for attachment to a bumper, the bumper mounted at an angle on the support post. 
         [0014]    In accordance with another aspect of the forgoing embodiment, the outrigger includes a bumper having a first side adapted for attachment to the outrigger and a second side adapted for contact with the boat. Ideally, the bumper includes wedges adapted to expand and contract. 
         [0015]    In accordance with yet a further aspect of the forgoing embodiment, the support post is adjustable in length. 
         [0016]    In accordance with yet another aspect of the forgoing embodiment, a length between the mount and the first end of the lever arm is a first length and a length between the second end of the lever arm and the mount is a second length, and the first length is greater than the second length. Ideally, the first length and the second length are independently or dependently adjustable. 
         [0017]    In another embodiment of the invention, a boat centering assembly for a trailer is provided. The assembly includes at least two independent lever arms, each lever arm having a first end and a second end, the lever arms adapted to rotate in a plane that is perpendicular to the longitudinal axis of the trailer; at least two bearing members on the first end of each lever arm and configured to rotate the lever arm when contacted by the boat hull; at least two outriggers mounted on the second end of each lever arm and configured to urge the boat towards the center of the trailer when each lever arm rotates in a first direction; and a respective biasing member associated with each lever arm that biases each lever arm to rotate in a second direction to move the outrigger away from the boat hull when the boat is centered on the trailer. Ideally, the biasing member includes a torsion spring. 
         [0018]    In accordance with a further aspect of the forgoing embodiment, the at least two bearing members include a support post having a first end adapted for attachment to the first end of the lever arm, and a second end adapted for attachment to a bumper, the bumper mounted at an angle on the support post. 
         [0019]    In yet another embodiment of the invention, a method for centering a boat on a trailer is provided. The method includes biasing a lever arm in a first position away from the center of the trailer; moving the boat closer to the trailer so that the lever arm rotates a second end of the lever arm away from the first position to a second position towards the boat to center the boat with respect to the trailer; and fully resting the boat in a laterally centered position on the trailer and in contact with the first end of the lever arm (e.g., via a contact member) and not in contact with the second end of the lever arm. 
         [0020]    In accordance with a further embodiment of the invention, a boat centering assembly for a trailer is provided. The assembly includes a device for rotating about an axis substantially parallel to the longitudinal axis of the trailer; a device for contacting the boat, the contacting device mounted on the rotating device; and a device for urging the boat towards the longitudinal axis of the trailer when the contacting device is in contact with the boat and to not contact the boat when the boat is centered on the trailer, the urging device mounted on the rotating device. 
         [0021]    In accordance with a further aspect of the forgoing embodiment, a device is provided for biasing the urging device in a direction that will move the contacting device upwards when the contacting device is not in contact with the boat. Ideally, the biasing device includes a torsion spring. 
         [0022]    In accordance with yet a further aspect of the forgoing embodiment, the contacting device includes a support post having a first end adapted for attachment to the first end of the lever arm, and a second end adapted for attachment to a bumper, the bumper mounted at an angle on the support post. 
         [0023]    In another embodiment of the invention, an improved boat trailer is provided, the boat trailer having a frame, at least one cross member, at least one bunk mounted to the at least one cross member, at least one axle, a plurality of wheels attached to the at least one axle, a hitch assembly attached to the frame is provided. The improvement includes at least two lever arms, each lever arm having a first end and a second end. Preferably, the lever arms are adapted to rotate in a plane that is substantially perpendicular to the longitudinal axis of the trailer. The improvement further includes at least one bearing member, on the first end of each lever arm, and configured to rotate the lever arm when contacted by the boat hull; at least one outrigger mounted on the second end of each lever arm and configured to urge the boat towards the center of the trailer when each lever arm rotates in a first direction; and a respective biasing member associated with each lever arm that biases each lever arm to rotate in a second direction to move the outrigger away from the boat hull when the boat is centered on the trailer. 
         [0024]    In yet a further embodiment of the invention, a kit that adapts a boat trailer to self-center a boat hull on the trailer is provided. The kit includes at least two lever arms adapted for pivotal connection to the trailer to move independently about an axis that is substantially parallel to a longitudinal axis of the trailer, each lever arm having at least one mounting opening, a first end, and a second end; a first contact member adapted for attachment to the first end of the lever arm and structured for contact with a bottom of the boat hull; a second contact member adapted to be attached to the second end of the lever arm and structured to bear against a side of the boat hull; and a mounting assembly for mounting each lever arm independently to the trailer frame, the mounting assembly including a biasing member for urging the lever arm to independently rotate in a direction that moves the second contact member away from a longitudinal axis of the trailer. 
         [0025]    In accordance with a further aspect of the forgoing embodiment, the mounting assembly includes at least one axle for each of the at least two lever arms, the axle adapted to be attached to the trailer and to receive the mounting opening of the corresponding lever arm, and the biasing member comprising a torsion spring. Ideally, a retaining member is provided for each of the at least two lever arms and adapted to hold each lever arm in a position where the lever arm is rotated towards the longitudinal axis of the trailer. 
         [0026]    In accordance with yet another aspect of the forgoing embodiment, a distance between the first end and the mounting opening includes a first length and a distance between the second end and the mounting opening includes a second length, wherein the first length is greater than the second length. 
         [0027]    As will be readily appreciated form the foregoing, the disclosed embodiments of the present invention provide a new device for centering a boat on a trailer frame and correct the issues listed above. In particular, the lever arm is biased to rotate the outrigger outward and away from the boat hull. The outrigger does not contact the boat when the boat is centered on the trailer. This feature prevents scraping along the boat hull when the boat is being loaded on the trailer and further prevents damage to the hull during transport. 
         [0028]    The device is also designed to accommodate boat hulls of various shapes and sizes. In particular, the length of the lever arm and the contact member may be adjustable and further provide the lever arm the ability to achieve a greater mechanical advantage when the boat hull shape and size allow. 
         [0029]    Additionally, the device is easily adaptable to existing trailers. In accordance with one embodiment of the invention, the device is provided in a kit that allows installation of the device to any conventional boat trailer. This embodiment further allows the user to choose the number of devices to install based on preference and the shape and size of the boat. Thus the new design provides improved flexibility while providing effective centering of a boat on a trailer. 
     
     
       BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING(S) 
         [0030]      FIG. 1  is an isometric view of a conventional boat trailer. 
           [0031]      FIG. 2  is a top view of a conventional boat trailer modified to include a boat centering assembly formed in accordance with one embodiment of the invention. 
           [0032]      FIGS. 3A-3B  are end views of a conventional trailer adapted to include a boat centering assembly, in accordance with one embodiment of the invention, when the boat is floating above the trailer and when the boat is fully rested on the trailer respectfully. 
           [0033]      FIG. 4  is a side view of a boat centering device formed in accordance with one embodiment of the present invention. 
           [0034]      FIG. 5  is a side view of an outrigger formed in accordance with one embodiment of the invention. 
           [0035]      FIG. 6  is a side view of a contact member attached to a lever arm. 
           [0036]      FIG. 7  is a top view of a lever arm and corresponding mounting assembly according to one embodiment of the invention. 
           [0037]      FIG. 8A  is a top view of a safety device attached to a mount in accordance with one embodiment of the invention. 
           [0038]      FIG. 8B  is a side view of the safety device attached to a mount in accordance with one embodiment of the invention. 
       
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
       [0039]    A representative embodiment of the present invention will now be described in conjunction with  FIGS. 2-8 .  FIG. 2  shows a boat trailer  14  with a trailer frame  16  modified to include a boat centering assembly  30 , according to one embodiment of the invention. The boat centering assembly  30  includes four of the devices  30  mounted on opposite sides of the trailer frame  16 . The front two devices  30  ensure centering of the bow while the rear two devices  30  ensure centering of the stern. It is preferred, in one embodiment, that for boats sixteen feet and longer, at least four of the devices  30  be used in order to ensure efficient centering of the boat  10  on the trailer  14 . However, it is understood that any number of the device  30  will center the boat  10 . For example, a single device  30 , an assembly of at least two devices  30 , or an assembly of four or more devices  30  can all be used, depending on the type of boat  10 , the size of the trailer  14 , and user preference. 
         [0040]    In one embodiment, the boat centering device  30  may be in a kit form to adapt a trailer  14  to become self-centering. In another embodiment, the boat centering device  30  may be manufactured as an integral component of the trailer  14 . 
         [0041]      FIG. 3A  and  FIG. 3B  show one embodiment of the invention where a boat centering assembly  30  is used on the boat trailer  14  to guide the boat  10  having a hull  12  onto the trailer  14 . In  FIG. 3A , the boat  10  is floating above the trailer  14  in water. In  FIG. 3B , the boat  10  is fully resting on the bunks  18 . The boat centering assembly  30  includes at least two lever arms  32  that are mounted to the trailer  14 . Preferably, each lever arm  32  rotates in a plane that is approximately perpendicular to the longitudinal axis of the trailer  14  and towards the center of the trailer frame  16 . Contact members  36  are attached to a first end  33  of each lever arm  32  while outriggers  44  are mounted on a second end  35 . When a bottom  13  of the boat hull  12  bears against the contact member  36 , the lever arm  32  will rotate. The second end  35  of each lever arm  32  is thus rotated towards the center of the trailer  14  so that the outriggers  44  move towards each other, and at least one of the outriggers  44  will contact a side  15  of the hull  12  to urge the boat  10  towards the center of the trailer  14 . In other words, when the boat  10  is positioned off center and towards one side of the trailer  14 , the outrigger  44  on that side of the trailer  14  will contact the hull  12  and urge the hull  12  to move back towards the center of the trailer  14 . 
         [0042]    Biasing members  38  are associated with each lever arm  32  to bias the lever arms  32  to rotate the outriggers  44  away from each other. Ideally, in one embodiment, the outriggers  44  are configured to not contact the boat hull  12  when the boat  10  is centered and resting on the trailer  14 . For example, when the boat  10  is centered and resting on the trailer  14 , each outrigger  44  will be spaced away from the side of the boat hull  12  a distance in the range of ¾ inch to 1.5 inches, and preferably about one inch. Thus, for a hull that is 79 inches in width, the outriggers will be separated approximately in the range of 80.5 inches to 82 inches and preferably about 81 inches. This will prevent rubbing of the outrigger  44  against the hull  12  while in transport. 
         [0043]    In one embodiment, the biasing members  38  rotate the lever arms  32  in such a direction as to cause the outriggers  44  to move away from the center of the trailer  14  and over the edge of the trailer frame  16  when the boat  10  is not in contact with the contact members  36 . Preferably, the outriggers  44  are angled away from the boat  10  at about eighteen degrees from the vertical edge of the trailer frame  16 . However, it is understood that other angles may be used. 
         [0044]    In accordance with another embodiment of the invention,  FIG. 4  illustrates a side view of the boat centering device  30 . The device  30  includes a lever arm  32  mounted on a mount  34  on the trailer  14 . Ideally the lever arm  32  will rotate about an axis that is approximately parallel to the longitudinal axis of the trailer  14 . However, it is to be understood that the lever arm  32  can rotate on an axis having a different orientation to achieve a different mechanical advantage or to accommodate boat and trailer designs. An outrigger  44  is mounted on the second end  35  of the lever arm  32 , while the contact member  36  is mounted on the first end  33 . In one embodiment, the lever arm  32  includes a mounting opening to receive a mounting assembly for mounting the lever arms independently to the trailer frame. Ideally, in the foregoing embodiment, the mounting assembly includes at least one axle (not shown) that attaches to the trailer and receives the mounting opening. In another embodiment, the lever arm  32  is formed to correspond to the shape of the trailer frame  16 . Here, the lever arm  32  comprises three bars  27 ,  29 , and  31  joined together to be positioned around the trailer frame  16  without contacting the trailer frame  16 . The lever arm  32  pivots on the mount  34 , as shown in  FIG. 4 . Ideally, the lever arm  32  is formed of steel, although it is understood that other material may be used, such as plastic or aluminum. The material is treated to withstand corrosion from either or both salt water and fresh water. 
         [0045]    In yet another embodiment, the lever arm  32  includes an adjustment bar  48  that adjusts the location of the contact member  36  and an adjustment bar  50  that adjusts the location of the outrigger  44 . The adjustment bars  48  and  50  are slidably engaged over the respective first and second ends  33 ,  35  of the lever arm  32  and retained in place by suitable fasteners  49  to allow the device  30  to accommodate boats of various shapes and sizes. 
         [0046]    In  FIG. 4 , the outrigger  44  is adapted to urge the boat  10  towards the center of the trailer  14  when the boat  10  is in contact with the contact member  36 . The outrigger  44  is also adapted to maintain a distance of separation from the boat hull  12  when the boat  10  is centered on the trailer  14  and resting on the bunks  18 , as shown in  FIG. 3B . The distance of separation is important because it ensures that the hull  12  is not damaged in transport, by the outriggers  44 . 
         [0047]    As shown in  FIG. 4  and again in  FIG. 5 , the outrigger  44  includes a bumper  46  preferably formed of plastic, although other materials can be used. In one embodiment, the outrigger  44  includes adjustable wedges  56  that are configured to have adjustable dimensions, such as by expansion and contraction, to accommodate boat hulls of various shapes and sizes. 
         [0048]    In  FIG. 4 , contact members  36  preferably include a support post  40  that attaches to the lever arm  32  at one end  37  and have a bumper  42  attached at the other end  39 , as shown in  FIGS. 4 and 6 . The bumper  42  is preferably formed of polyethylene and has a rectangular base  58  with a curved head  60 . As shown in  FIG. 6 , the bumper  42  is preferably mounted to have a fixed angle laterally with respect to the longitudinal axis of the support post  40 . The preferred shape and position of the bumper  42  allows the device  30  to accommodate the chine of the boat  10  without causing damage to the boat hull  12  during movement of the hull  12  or by constraining movement of the boat  10  on the trailer  14 . However, other methods of support can be used for the contact member  36 , such as a nonadjustable post without a bumper or a support post with a bumper of a different shape, for example, one that includes a square or triangular head. In one embodiment, the support post  40  also includes an adjustment bar  52  that varies the length of the support post  40  in order for the device  30  to adapt to different sizes and shapes of trailers and boat hulls. 
         [0049]    As further shown in  FIG. 4 , in one embodiment, the biasing member  38  is also associated with the device  30 . The biasing member  38  rotates the lever arm  32  in a direction that will move the contact member  36  upward when the boat hull  12  is not in contact with the contact member  36 . For example, the contact member  36  will move upward when the device  30  is not in use or when the boat  10  is floating above the device  30  and has not yet come to rest on the trailer  14 . It is preferred that the biasing member  38  include a torsion spring  54 , as shown in  FIG. 7 . However, it is understood that other methods for biasing may be used that are known to those skilled in the art. In one embodiment, the biasing member  38  is housed within the mount  34  while the mount  34  is attached to the lever arm  32  and the trailer frame  16 , as shown in  FIG. 4 . 
         [0050]    In order for the lever arm  32  to achieve the greatest mechanical advantage, it is preferred that the length between the mount  34  and the contact member  36  on the first end  33  be greater than the length between the mount  34  and the outrigger  44  on the second end  35 . To this end, it is preferred to construct the lever arm  32  such that the distance between the mount  34  and the proximal end  51  of the adjustment bar  48  is greater than the distance between the mount  34  and the proximal end  53  of the adjustment bar  50 . The adjustment bars  48  and  50  can further be used to adjust the ratio of the two lengths in order to achieve an even greater mechanical advantage when the shape and size of the boat  10  allow. However, it is understood that other alternative methods of determining the ratio can be used, such as using a lever arm that is completely adjustable in length. 
         [0051]      FIG. 8A  illustrates a safety device in accordance with another embodiment of the invention. The safety device  70  includes a detent pin  80  having a double failsafe key ring  72  and pin  74 . The detent pin  80  is used to secure the lever arm  32 , and thus the outrigger  44 , in a position where the lever arm  32  and the outrigger  44  are rotated towards the center of the trailer  14 . In the embodiment where the biasing member  38  rotates the lever arm  32  in such a direction as to cause the outrigger  44  to move away from the center of the trailer  14  and over the edge of the trailer frame  16 , the safety device  70  is used to store the outrigger  44  in a position that will cause the outrigger  44  to remain within the boundary of the trailer frame  16 , and thus prevent damage to the outrigger  44  and to objects that the outrigger  44  may hit. In one embodiment, a detent ball  78  is used to secure the position of the detent pin  80 . In yet another embodiment, the safety device  70  is encased in a housing  76  and attached to the mount  34 , as shown in  FIG. 8B . 
         [0052]    In construction, the various components of the device  30  are preferably attached together using either conventional bolts, tension bolts, or welded together to form a rigid structure. However, it is to be understood that other methods of attachment may be used, including fasteners, tightly-fitted joints, and other methods known to those skilled in the art. 
         [0053]    All of the above U.S. patents, U.S. patent application publications, U.S. patent applications, foreign patents, foreign patent applications and non-patent publications referred to in this specification and/or listed in the Application Data Sheet, are incorporated herein by reference, in their entirety. 
         [0054]    From the foregoing it will be appreciated that, although specific embodiments of the invention have been described herein for purposes of illustration, various modifications may be made without deviating from the spirit and scope of the invention. Accordingly, the invention is not limited except as by the appended claims.