Abstract:
A davit lift for small boats can be pivotally coupled to a rearwardly projecting horizontal surface of a boat. The davit lift includes a cradle formed of multiple tubular members arranged to support a small boat. Apertures formed in one end of the tubular members are alignable with apertures in a pair of mounting brackets affixable to a boat to receive lock pins. Selective engagement and disengagement of the lock pins allows the cradle to be pivoted from its deployed position, an upright storage position and a forward inclined transport position.

Description:
CROSS-REFERENCE TO CO-PENDING APPLICATION 
     This application claims priority benefit to the Mar. 24, 2014 filing date of U.S. Provisional Patent Application Ser. No. 61/969,500, filed in the name of Otto L. Isbill, for a Davit Cradle Lift For Small Boats, the entire contents of which are incorporated herein in its entirety. 
    
    
     BACKGROUND 
     There are examples of lift devices attachable to the transom and/or the swing platform of large boats to launch or lift and carry the small boats next to the transom of the larger boats. 
     Such lift devices include arms or cradles mounted to a rear surface or platform of a boat. Some cradles are hinged to permit the cradles to be rotated upwardly sometimes more than 90°, to raise a small boat mounted in the cradle up and out of the water for easy transport with a larger boat. 
     However, such previous small boat lifts are cumbersome, large or difficult to use and may render the rear portion or swim platform of the larger boat somewhat unusable for its intended purpose. 
     SUMMARY 
     A davit cradle lift for boats with a rearwardly projecting horizontal surface. The davit cradle lift includes a cradle formed of two spaced longitudinally extending members, each having first and second opposed ends, and a third laterally extending member connected adjacent the second ends of the first and second longitudinally extending members. Two spaced apertures formed in an arcuate section extending from a linear end portion of the first ends of each of the first and second tubular members. A pair of mounting brackets is affixable to a horizontal rearward extending surface of a boat. The mounting brackets carrying first and second pairs of spaced apertures. First and second pins are respectively mountable in an upper most pair and a lower most pair of the aligned aperture pairs in the first and second mounting brackets. The first and second pins extend through one aperture of the aperture pairs in the first end portion of each of the first and second tubular members. The first and second pins are removable and insertable both at the same time, or only the second pin, or only the upper pin, to allow the cradle to move between a lowered position where the cradle is disposed in the water to launch or retrieve a dinghy, and at least a first generally vertically extending upright storage position. 
     To achieve the boat launch and retrieval position, the pin is removed from the apertures in the mounting bracket and the first ends of the longitudinally extending first and second tubular members of the cradle. 
     The first storage position is secured by inserting both of the first and second pins into the aligned pairs of apertures in the mounting bracket and the apertures in the first ends of the first and second tubular members of the cradle after the cradle has been pivoted to a generally upright portion. 
     The forward angled storage position is achieved by removing the second pin from the aligned apertures in the mounting bracket and the first and second longitudinally extending members of the cradle to allow the cradle to pivot about the first pin in the pair of apertures in the mounting brackets and one aperture in the first end of the first and second longitudinally extending members to a forward inclined position. 
     The pair of mounting brackets can include a first leg portion mountable to a boat surface, and a vertically extending portion. Upper and lower pairs of arms are fixedly coupled to a vertical portion of each mounting bracket. Apertures are formed in the pairs of arms for receiving the pins. 
     A stop member may be mounted on the vertical portion of the mounting brackets, to provide a reference surface for aligning the apertures in the longitudinally extending members of the cradle of the apertures in the arms. 
     In another aspect, each mounting bracket includes the first leg portion defining a linear leg portion; the vertical portion extending from one end of the first leg portion; and an angled section extending from an end of the vertical portion to a fixed connection with the first leg portion. 
     A fourth laterally extending member may be provided adjacent the first ends of the first and second longitudinally extending members. 
     The davit lift can further include each of the longitudinally extending tubular members having a first leg portion extending from a curved portion adjacent the first end and extending toward the opposite longitudinally extending member. A second leg portion extends from the second end of each longitudinally extending tubular member, the second end portions having opposed ends facing the opposite tubular member. Connectors fixedly couple ends of the first and second leg portions of each of the longitudinally extending members into a unitary configuration. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWING 
       The various features, advantages and other uses of the present davit cradle lift for small boats will become more apparent by referring to the following detailed description and drawing in which: 
         FIG. 1  is a perspective view of a davit cradle lift for small boats shown in a downward deployed position for loading and unloading a small boat from the cradle lift; 
         FIG. 2A  is an enlarged perspective view showing one mount of the cradle lift of  FIG. 1  on a swim platform of a boat; 
         FIG. 2B  is an enlarged cross-sectional view showing the pin entry apertures in the tubing; 
         FIG. 3  is a side elevational view of the davit cradle lift shown in a deployed position of  FIG. 1 ; 
         FIG. 4  is a side elevational view showing the davit cradle lift of  FIGS. 1-3  depicted in a raised, substantially vertical storage position; 
         FIG. 5  is a side elevational view showing the davit cradle lift of  FIGS. 1-4  in a forward inclined, transport position; 
         FIG. 6  is a side elevational view of another aspect of a davit cradle lift; 
         FIG. 7  is a exploded, perspective view showing one of the mounts to the davit cradle lift depicted in  FIG. 6 ; 
         FIG. 8  is a side elevational view showing another aspect of a davit cradle lift; 
         FIG. 9  is a plan view of another aspect of a mount for a davit cradle lift; 
         FIG. 10  is a perspective view showing a pair of mounts, one of which is depicted in  FIG. 9 , mounted on a boat and supporting the davit cradle in a deployed position; 
         FIG. 11  is a perspective view of one of the mounts shown in  FIGS. 9 and 10 ; 
         FIG. 12  is a side elevational view showing the davit cradle lift of  FIGS. 9-11  in a vertical storage position; 
         FIG. 13  is a side elevational view showing the davit cradle lift of  FIGS. 9-11  in a forward inclined, transport position; 
         FIG. 14  is a plan view of another aspect of a davit cradle lift; 
         FIG. 15  is a side elevational view of another aspect of a cross arm for one of the davit cradle lifts shown in  FIGS. 1-13 ; and 
         FIG. 16  is a plan elevational view showing another aspect of the cross arms of a davit cradle lift, one of which is depicted in  FIG. 15 . 
     
    
    
     DETAILED DESCRIPTION 
       FIG. 1  depicts a swim platform  10  in the form of a generally horizontally extending ledge located adjacent to a transom of a boat. The swim platform  10  has a horizontally extending surface  12  and a vertically extending outer ledge  14 . 
     A davit cradle lift  20  is positioned rearward of the swim platform  12 . The davit lift  20  includes a mounting assembly  22  formed of two pairs of brackets  24 , show in  FIGS. 1-5 . Each bracket  24  has first and second perpendicularly oriented legs  26  and  28 . The first and second legs  26  and  28  are fixed to the swim platform  12  by fastening means, such as fasteners in the form of screws, bolts, etc. Although the legs  26  and  28  of the bracket  24  are shown laying over the horizontal surface  12  and the vertical surface  14  of the swim platform  10 , it is possible to form the first bracket  24  with just a single leg portion  28  fixed to the vertical extending portion of the swim platform  10 . 
     A second bracket  30  is fixed to the vertically extending second leg  28  of the first bracket  24  by suitable fasteners  32 , shown in detail in  FIG. 2 , which extend through aligned apertures in the second bracket  30  and the second leg  28  of the first bracket  24  into vertically extending surface  14  of the swim platform  10 . 
     The second bracket  30  has a general U-shaped formed of first and second spaced walls  34  and  35 , which are joined along an intermediate portion by a central wall  36  carrying the apertures for the fasteners  32  used to join the second bracket  30  to the first bracket  24  and/or to the vertical surface  14  of the swim platform  10 . 
     By way of example, the central wall  36  has first and second ends  38  and  40  which terminate short of the outermost ends of the walls  34  and  35 . An aligned pair of apertures  42  is formed in one end of the walls  34  and  35 . The second pair of apertures  44  are formed in the opposed ends of the walls  34  and  35 . The first pair of lower located apertures  42  are disposed below the upper located second pair of apertures  44 . The pair of apertures  42  and  44  receive a removable lock pins, such as a first pin  50 , removably mountable through the pair of aligned apertures  42 , and a second pin  52  removably mountable through the other pair of aligned apertures  44 . 
     The davit lift  20  includes a cradle assembly  60 . The cradle assembly  60  is formed of joined tubular members including first and second longitudinal tubular members  62  and  64  and a third laterally extending tubular member  66  fixed to the end of the first and second tubular members  62  and  64 . 
     The tubular members  62 ,  64 , and  66  are formed of a suitable corrosion resistant material, such as aluminum or stainless steel. Aluminum is ideal for use in fresh water; while stainless steel is ideal for use in saltwater. 
     The first and second tubular members  62  and  64  have substantially identical shapes formed of a first end  66 , a curved end portion  68 , and a generally shallow V-shaped portion  70  which extends to a second end  72 . The V-shape portion  10  of the tubular member  62  or  64  is by example as the portion  70  may alternately have a generally linear shape. The V-shape is suitable for use with small boats, such as inflatable dinghy which have a rigid V-shaped hull. 
     The curved portion  68  of the first tubular member  62  or the second tubular member  64  extends from a generally linear end portion  74  extending from the first end  66  through an approximate 180° bend to the start of the longitudinal portion  70 . 
     The linear end portion  74  of each of the first and second tubular members  62  and  64  includes first and second spaced apertures  76  and  78 . The apertures  76  and  78  are spaced apart the same distance as the spacing between the apertures  42  and  44  in the walls  34  and  35  of the second bracket  30 . 
     The outer ends of the apertures  76  and  78  are flared, ad shown in  FIG. 2B . A tubular sleeve  71  as having a first flared end  73  and then opposed flared end  75  disposed on opposite ends of a tubular portion  77 . The sleeve  71  is initially provided with one flared end, such as flared end  73  prior to insertion of the tubular portion  77  through one aperture  44  and the tubular member  64  until the opposite end of the tubular portion  77  is disposed within the opposed aperture  44  in the tubular member  64 . The end of the tubular portion  77  is then bent outward into the flare  75  shown in  FIG. 2B . The tubular sleeve  71  provides for ease of inserting the lock pins  50  and  52  through the apertures  76  and  78  in each tubular member  62  and  64 . 
     The third tubular member  66  extends laterally between the spaced tubular members  62  and  64  and is fixed to the second ends  72  of the first tubular members  62  and  64  to complete the cradle  20 . The third tubular member  66  is spaced from the inner surfaces of the curved end portion  68  of the first and second tubular members  62  and  64  by a distance suitable for slidably receiving the inflatable pontoons  76  of a small dinghy. 
     It should be noted that the radius of the curved end portion  68  at the first end of the tubular members  62  and  64  is sized to receive one inflatable pontoon  76  of a dinghy. 
     The removable lock pins  50  and  52  in combination with the second mounting brackets  30  and the apertures  76  and  78  in the curved end portion  68  of the first and second tubular members  62  and  64  enables a dinghy to be launched and retrieved from the cradle position shown in the  FIGS. 1 and 3 , stored in a generally vertically extending upright position shown in  FIG. 4  where the entire horizontal surface  12  of the swim platform  10  is still accessible for use, to a forward angular extending storage position shown in  FIG. 5  typically for use during periods of movement of the large boat. 
       FIGS. 2 and 4  show the lock pins  50  and  52  inserted through the respective pairs of apertures  42  and  44  in the second mounting bracket  30  and the apertures  76  and  78  in the first end  74  of each of the first and second tubular members  62  and  64 . This supports the davit lift  20  and the dinghy mounted therein in a generally vertical extending storage position. 
     In this vertically extending position, the davit lift  20  enables the horizontal surface  12  of this the swim platform  10  to be freely accessible. 
     Removal of the uppermost or second lock pin  52  enables the cradle  60  to be pivoted about the lower lock pin  50  to a lowered dinghy launch and retrieval position shown in  FIGS. 1 and 3 . In this position, the cradle  60  rest in the water to enable to dinghy is pushed out of the cradle  60  for launching or moved into the cradle for retrieval. 
     In the dinghy retrieval position shown in  FIG. 3 , a strap  80  attached to winch generally shown by reference number  81  affixedly mounted on the large boat, such as on a transom, a transom rail, or other convenient mounting position, is secured at an outer end to the third laterally extending tubular member or tie bar  66 . The winch  81  enables the entire cradle  60  to be pivoted and raised about the pivot axis formed by the pivot pin  50 , the aligned apertures  42  and mounting bracket  30  and the first aperture  76  in each of the tubular members  62  and  64 . A reverse winch operation lowers the cradle  60  carrying the dinghy to the launch position shown in  FIGS. 1 and 3 . 
     With the dinghy positioned in the cradle  60  as shown in  FIGS. 1 and 3 , the winch  81  may be rotated to pull in the strap  80  thereby pivoting the cradle  60  about the pivot axis of the lower pins  50  to a first, generally vertically extending storage position shown in  FIG. 4 . 
     In this position, the second apertures  78  in the tubular members  62  and  64  fit between the walls  34  and  35  of the second mounting bracket  70  in a line with the pair of apertures  44  in the walls  34  and  35  of the second mounting bracket  30 . The upper lock pin  52  may then be inserted into the aligned apertures  44  and  76  to lock the cradle  10  in the first vertically extending storage position shown in  FIG. 4 . 
     For extended travel of the large boat, the winch  81  may be rotated to further pull the strap  80  toward the boat transom as noted by reference  86  in  FIG. 5  after the lower lock pin  50  has been removed from the aligned apertures  42  and  76 . This allows the curved end portion  68  of the tubular members  62  and  64  to pivot about a pivot axis formed by the upper lock pin  52  mounted in the aligned apertures  44  and  78  to enable the entire cradle  10  to pivot from the generally 90° storage position shown in  FIG. 4  approximately 45° forward toward the boat transom  86 . This lowers the uppermost edge of the dingy for more aero dynamic movement of large boat through the water. 
     Referring now the  FIGS. 6 and 7 , there is depicted a modification to the first bracket now illustrated by reference number  80 . The first bracket  80  is formed of a suitable corrosion resistant material, such as aluminum for freshwater use and stainless steel for saltwater use. The first mounting bracket  80  includes an elongated first leg  82  adapted to overlay the top or horizontal surface  12  of the swim platform  10 . One or more apertures  84  are formed in the first leg  82  for receiving fasteners to secure the first leg  82  of the first bracket  80  to the horizontal surface  12  of the swim platform  10 . 
     The first bracket  80  also includes a rigid frame structure  86 , which can be integrally formed with the first leg  82  and which includes a plurality of generally linear legs including a second leg  88 , a third leg  90  disposed generally parallel to the first leg  82 , a fourth leg  92  and a fifth leg  94 . It will be understood that the frame structure  86  may also have other shapes, including any polygonal shape, such as square, rectangular, triangular etc., as well as a smoothly curved constant radius, circular shape. 
     The second leg  88  depends from one end of the first leg  82  and is generally spaced a predetermined distance from the vertical surface  14  of the swim platform  10  to allow sufficient room beneath the first mounting bracket  80  for pivotal movement of the tubular members  62  or  64 , as described above. One or more apertures  96  are formed in the second leg  88  for receiving fasteners to secure the second bracket  70  to the second leg  88  of the first bracket  80  in the same manner as shown in  FIG. 1 . 
     As shown in  FIGS. 6 and 7 , the fourth leg  92  slightly spaced apart or in contact with the vertical surface  14  of the swim platform  10 . By example, a fourth leg  92  may abut a rub rail  98  extending laterally across the vertical surface  14  of the swim platform  10 . 
     A fifth leg  100  is disposed adjacent to the first leg  82  and secured to the first leg  82  by suitable means, such as fasteners, including screws, or welding, adhesive, etc. 
     Referring now to  FIG. 8 , there is depicted another aspect of a mounting bracket for the davit cradle lift. In this aspect, each of the pair of mounting brackets attached to the swim platform includes a first plate  110  in the form of a long substantially linear leg which terminates in an angular flange  114 , such as a 90° flange. Apertures are spaced along the linear leg  110  and receive fasteners, not shown, to secure the linear leg  110  to the swim platform in the same manner as the bracket  80  shown in  FIG. 7 . 
     The shorter outer leg  114  is fixed by one or more fasteners  116  to an intermediate portion of a multi-angular bent second bracket  120 . The second bracket  120  includes a first end flange  122  fixed by fastener  124  to the leg  112 . An angular leg  126  extends from the first end flange  122  and terminates in an upper generally horizontally extending leg  128 . A vertical leg  130  extends from an outer end of the upper leg  128  to a lower leg  132  which is substantially parallel to the upper leg  128 . The lower leg  132  projects inward toward the swim platform  10  and transitions into a short vertical leg  136  which ends in an end flange  138  fixed by a fastener  140  to the leg  112 . 
     A pair of U-shaped mounting arms, including an upper arm assembly  140  and a lower arm assembly  142 , is fixed at an intermediate or central leg portion to the vertical leg  130  of each second bracket  120 . The upper and lower arm assemblies  140  and  142  are spaced apart and have braces  144  on each arm of each upper and lower arm assemblies  140  and  142  extending angularly from outer ends of each arm of the upper and lower arm assemblies  140  and  142 . The braces  144  may be welded to the upper and lower arm assemblies  140  and  142  and carry apertures aligned with the apertures  146  and  148  in the upper and lower arm assemblies  140  and  142 , respectively, for receiving the lock pins  50  and  52 . 
       FIGS. 9-13  depict another aspect of a davit cradle lift  150 . The cradle assembly for the davit cradle lift  150  is substantially the same as the cradle assembly  60  shown in  FIG. 1 . 
     In this aspect, however, a pair of mounting brackets  152  and  154 , substantially identically constructed, are mounted on the swim platform  10  and are removably coupled by the lock pins  50  and  52  to the cradle assembly  60  to enable the cradle assembly  60  to be moved between the deployed position shown in  FIG. 10  for loading and unloading a small boat to and from the cradle assembly  60 , to a substantially vertical position shown in  FIG. 12 , or to a forward inclined transport position shown in  FIG. 13 . 
     Each mounting bracket  152  and  154  includes a single multi-section bent plate  160 ; although separate pieces can be welded or secured together to form the one piece plate  160 . The plate  160  includes apertures  162  for attachment by fasteners to the swim platform  10 . The plate  160  includes a first long linear leg  166  which transitions in a substantially 90° bend to a vertically extending outer leg  168 . The outer leg  168  transitions to an angular, such as a 90° bent, upper leg  170  to an angular leg  172  which terminates in an end flange  174  having an aperture for receiving a fastener for securing the end flange  174  to the first leg  166 . 
     An upper arm assembly  180  and a lower arm assembly  182  are fixed by fasteners to the vertical leg  168  of the mounting bracket  152  or  154 . The upper arm assembly  180  is formed of first and second spaced side arms  184  and  186  which extend generally angularly or perpendicularly from a central leg  188  which receives the fastener for attaching the upper arm assembly  180  to the mounting bracket  160 . 
     The lower arm assembly  182  is similarly formed, but with longer length side arms  190  and  192  which extend angularly or perpendicularly from a central leg  194  which carries an aperture for receiving the fastener for attaching the lower arm assembly  182  to the vertical leg  168  of the mounting bracket  160 . 
     Apertures  194  are formed in each of the side arms  184  and  186 , and  190  and  192  of the upper and lower arm assemblies  180  and  182  for receiving the lock pins  50  and  52 . 
     A stop  199 , in the form of an angle strap shown in  FIGS. 10-15 , is mounted on vertical leg  168  of the mounting brackets  152  and  154 . The outer surface of the stop  199  provides a rest surface for mounting the longitudinal cradle members  62  and  64  of the cradle assembly  60  in the mounting brackets  152  and  154 . An end portion of the tubular members  62  and  64  can be brought into engagement with the stop member  199  to assist in aligning the apertures in the mounting brackets  152  and  154  with the apertures in the tubular members  62  and  64 . 
     The davit cradle lift  150  operates in the same manner as the davit cradle lift shown in  FIG. 1 . With the upper lock pin  52  removed from the apertures in the end of the longitudinal tubular members of the cradle assembly  60  and the upper arm assemblies  180 , the cradle assembly  60 , can be lowered to a deployed position shown in  FIG. 10  for off-loading or on-loading a small boat  200  onto the cradle assembly tubular members. 
     Next, manually or by a winch, such as the winch  81  shown in  FIGS. 3 and 4 , the davit cradle lift  150  can be raised to a substantially vertical position shown in  FIG. 12  for storage of the small boat. In this position, the lock pin  52  is reinserted to the apertures in the upper arm assemblies  180  of both mounting brackets  152  and  154  and the apertures in the end legs of the tubular members of the cradle assembly  60  to lock the cradle assembly in the raised vertical storage position. Next, prior to movement of the large boat carrying the small boat  200 , the lower lock pins  50  in the lower arm assemblies  182  may be removed to enable the cradle assembly  60  to be pivoted forward to an angular inclined position shown in  FIG. 13  for more streamlined positioning of the small boat  200  during the movement of the large boat. 
       FIG. 14  depicts another aspect of the cradle assembly in which the first and second tubular members  210  and  212 , which have the V-shape, and the curved end portions shown in  FIG. 1  are provided with tee connectors  214  which have a threaded set screw for locked or fixed engagement of the outer ends of the tubular members  210  and  212  to the third laterally extending cross tubular member  216  extending through two tee connectors  214 . Similarly, the ends of the tubular members  210  and  212  adjacent to curved end portions of the tubular members  210  and  212  also receive tee connectors  214  for securing to a fourth laterally extending crosswise tubular member  220 . This four-sided arrangement for the cradle assembly  60  provides a rigid structure for supporting larger size or heavier small boats. 
     Referring now to  FIGS. 15 and 16 , there is depicted another aspect of a cradle assembly in which the first and second tubular members  240  and  242  each have a V-shaped center section  244  for supporting the hull of a small boat, as with the other aspects of the cradle assemblies described herein. One end portion of each of the first and second tubular members  240  and  242  extends through an angular or 90° bend  246  and  248 , respectively, to short length outer ends  250  and  252 . The ends  250  and  252  receive an internally disposed tubular collar  254  which can be secured to the ends  250  and  252  by fasteners  256 . 
     The opposite ends of the first and second tubular members  240  and  244  have the concave curved section  260  which terminates in a short length linear end portion  262  for the tubular member  240  and a short length end section  264  for the second tubular member  244 . Each short length end section  262  and  264  transitions through an angular or 90° smoothly curved bend  266  and  268 , respectively, into short length ends  270  and  272 . An internally disposed collar  274  is locked in position between the spaced ends  270  and  272  and fixed in place by fasteners  276  extending to the ends of each end portions  270  and  272  to lock both of the tubular members  240  and  242  into a rigid unitary structure.