Patent Publication Number: US-2006017257-A1

Title: Boat launching, retrieval, transport apparatus and method

Description:
CROSS REFERENCE TO RELATED APPLICATIONS  
      The present application claims the benefit of U.S. patent application Ser. No. 09/935,486 filed Aug. 22, 2001, and U.S. Provisional Application Ser. No. 60/278,167 filed Mar. 22, 2001. 
    
    
     FIELD OF THE INVENTION  
      The present application relates to an apparatus and method particularly adapted for the launching of a boat into the water, retrieving the boat out of the water, or both launching and retrieving the boat, as well as transporting the boat over a ground surface.  
     BACKGROUND OF THE INVENTION  
      Smaller boats are commonly carried on boat trailers and are placed into the water or taken back out of the water generally by first finding a boat launching site where there is a slanting support surface (generally gravel or asphalt) which slopes downwardly into the body of water. The trailer is backed downwardly down the boat ramp to a depth where the boat is able to float. Then the boat is disconnected and moved away from the trailer, with the trailer then being pulled back out of the water. However, while this procedure is used quite commonly for smaller boats, it is for a variety of reasons used less frequently (if at all) for larger boats.  
      In a marina, boats of various sizes are taken out of the water for services, repair and/or storage, and at a later time are placed back into the water. A typical marina faces various challenges in having an efficient and cost effective operation. For example, the real-estate for a marina is generally at a premium, and thus the real-estate in storing the boats must be used efficiently. Further, the moving the boats into and out of the water, and into and out of storage spaces should be desirably be accomplished in the minimum amount of time. Also, there is the problem of what be termed “traffic congestion” in moving a number of boats effectively.  
      It&#39;s not surprising that the larger boats present challenges well beyond those that are faced with handling the smaller boats. To the best knowledge of the inventor herein, in most marinas the larger boats are usually launched into the water or taken out of the water by means of a lifting device (e.g. a hoist). Straps or other devices are placed around the boat hull, and these are engaged by the hoist to move the boat into or out of the water. With a relatively large boat (as long as forty or fifty feet), a rather large hoist is required. Again, to the best knowledge of the Applicant, it has not been practical to use the boat trailer for such large boats. Also, if trailers of sufficient size are used for the larger boats, there is the consideration of the mobility (i.e. the ability to effectively move such a large boat within the confines of a sometimes crowded marina boat storage area).  
      A search of the U.S. patent literature has revealed a number of patents relating to the launching and retrieval of boats into and from a body of water, and these are the following.  
      U.S. Pat. No. 5,857,823 (MacEachern), shows a trailer made up of two support structures, namely a rear support structure 18 made up of parallel beams, and a forward structure 20, these being rigidly connected to one another. At the forward end of the structure 20, there is a connection to what is called “a self-propelled tug 14”. The tug has forward steering wheels 64 which are stated to operate as a conventional steering mechanism, and at the rear of the tug 14 there is a universal connection which is controlled by hydraulic cylinders. Thus, this universal joint can rotate about all three axes. Also, the rear wheels 24 of the trailer are mounted so that these can be raised or lowered individually or together.  
      U.S. Pat. No. 5,921,742 (Gearhart), shows an articulated roll-off trailer that is provided with a hinge so that it may bend in the middle, in an upward direction.  
      U.S. Pat. No. 5,228,713 (Kovach), shows a boat trailer that has an upper boat carrying a section 18, and a lower wheeled frame 19, that are pivoted in the tongue area. The boat carrying section remains level at the water&#39;s surface as the wheeled section follows the contours of the bank, or launching ramp.  
      U.S. Pat. No. 4,801,153 (Wilson), shows a trailer that is pivoted for easier loading. It may be backed along a bank or launching ramp, and tilted so the boat or other cargo slides or rolls off.  
      U.S. Pat. No. 4,395,185 (Waley), shows a boat trailer in which the wheel carrying frame is pivoted on the frame section on which the boat is mounted on. The wheel section follows the contours of the bank or the launch ramp, while the boat carrying part floats and is well oriented to load the boat.  
      U.S. Pat. No. 3,888,367 (Cox), shows a boat trailer with pivoted boat supporting elements that accommodate the contour of the boat bottom.  
      U.S. Pat. No. 3,768,677 (Moss) provides a boat trailer with wheels that can be adjusted relative to the trailer frame to accommodate the loading and unloading, on various bottom contours.  
      U.S. Pat. No. 3,608,754 (Park), shows a boat trailer in which the hitch and wheels are on a frame and a sub frame is pivoted at one end and supporting the boat at the other end. The sub frame supports the boat&#39;s stem and aligns it as it floats on or off the trailer.  
      U.S. Pat. No. 3,512,667 (Calkins), shows a boat trailer on which the boat support pivots and aligns with the boat as it is moved in or out of the water, while the wheeled sections are on a tilted bottom.  
      U.S. Pat. No. 3,155,249 (Johnson), shows a trailer that is provided with pivoting hull support elements.  
     SUMMARY OF THE INVENTION  
      The apparatus and method of the present invention is designed to launch boats into the water, and also retrieve boats out of the water in a particularly effective way. Also, in a preferred embodiment of the present invention, the apparatus is designed to be used in a manner so that the apparatus can be maneuvered effectively over a ground surface for better utilization of land space in a marina or the like.  
      The apparatus of the present invention comprises a main support frame having a longitudinal axis, a transverse axis, a front end and a rear end. The main support frame comprises a forward main frame section and a rear main frame section. The forward and rear main frame sections are pivotally connected to one another about a pivot location, so as to be able to be rotated relative to one another between an upper pivot configuration of the main support frame, with the pivot location at a higher elevation, and a lower pivot configuration of the main support frame with the pivot location at a lower elevation.  
      The forward and rear main frame section are arranged as right and left main frame side portions. Each of the main frame side portions comprises a forward and a rear main frame side portion, and right and left main frame side portions define therebetween a boat receiving region. This boat receiving region comprises a rear entry portion, a rear boat receiving region portion that is located between the right and left main frame rear side portions, and a forward boat receiving region portion located between the right and left forward main frame side portions.  
      There is a rear wheeled support section which is connected to the rear main frame section. This rear wheeled support section is moveable between upper and lower configurations relative to the main rear frame section. There is also a forward support section connected to the forward main frame section.  
      The apparatus is arranged so that with the apparatus in an operating position in a body of water, the rear main frame section is able to be located at a first lower ground elevation in the body of water, with the rear support section in its upper configuration and the main support frame in its lower pivot configuration. By lowering the rear support section, the rear main frame section is then at a higher ground elevation in a body of water.  
      In an embodiment shown herein, each of the main frame side portions has its own pivot connection between its related main frame side portion and main frame rear side portion.  
      More specifically, each of the rear main frame side portions can rotate independently from one another about its related pivot connection relative to its forward main frame side portion. Also, in this embodiment, the front and rear main frame side portions of each main frame side portion has a related actuator to move the rear main frame portion relative to its related forward main frame side portion.  
      In this embodiment, the rear wheeled support section comprises left and right wheeled rear support portions, each of which has a wheel portion and a related actuator to raise or lower the wheel portion.  
      Also, in the configuration shown herein the forward main frame section has a front end frame portion connected between forward end portions of the forward main frame side portions. At the forward support section there is a steerable wheel section. The steerable wheel section comprises in a preferred form at least two steerable wheels spaced laterally from one another with each steerable wheel having its own steering axis about which each steerable wheel can be rotated through various steering positions. Also, there is an operating station at the forward location of the forward main frame section by which an operator can control operation of the apparatus.  
      In a second embodiment of the present invention, the forward support section comprises a connection component adapted to be connected to a towing apparatus to move the transport apparatus.  
      In a preferred arrangement, the rear wheeled support section is arranged to provide ground support at a support location at a rear portion of the rear main frame section.  
      The rear support section has a rear ground engaging support location and the forward support section has a forward support location by which the forward main frame section is supported from a ground surface. The pivot location is located at a pivot location spacing distance between about one third to three quarters of a distance from said rear ground engaging support location to the forward support location. Within narrower limits, the pivot location spacing distance is no greater than about two thirds of the distance from the rear ground engaging support location to said forward support location. With yet narrower limits, the pivot location is between about two fifths to three fifths of the distance from the rear ground engaging support location to the forward support location. As an approximation, the pivot location is about one half the distance from the rear ground engaging support location to the forward support location.  
      The two rear main frame side portions each have a longitudinally extending boat engaging support portion. Each of the support portions comprises a longitudinally extending inflatable bunker to provide support for a boat being positioned thereon.  
      The apparatus is desirably arranged in size so as to be able to support a boat of a smaller length dimension, and also a boat up to a larger maximum length dimension extending into the forward boat receiving portion. The rear main frame section is configured and has a length such that a boat of the maximum length dimension being carried by the apparatus has a center of gravity which, when the boat is positioned on the apparatus, is behind the pivot location. Thus at least a substantial portion of the weight of the boat is supported by the inflatable bunkers.  
      The apparatus is arranged so that rear main frame section is able to support at least a substantial portion of weight of a boat having a lengthwise dimension at least as great as or greater than a lengthwise dimension of the rear main frame section so that when the boat is carried by the apparatus, a forward end portion of the boat extends into the forward boat receiving region portion. The right and left rear main frame side portions have longitudinally extending support surface portions which engage the boat and which are positioned in a boat support reference plane. The apparatus has a ground support reference plane which is defined at a rear support location by a rear ground support location of the rear support section and at the forward end of the apparatus by a forward ground support location of the forward support section. The apparatus is arranged so that with the rear support section in its lower configuration, and with the main support frame being in its lower pivot configuration, the boat support reference plane has a downward and forward slant relative to the ground reference plane.  
      Also, the apparatus is arranged so that with the rear support section being in its upper configuration and the main support frame being in its lower pivot configuration the downward and forward slope relative to the ground support reference plane is between about 2° to 12°.  
      Also, the apparatus is arranged so that with the rear support section being in its lower configuration and the main support frame being in its lower pivot configuration, the boat support plane of the apparatus has a forward and downward slope relative to the support reference plane. Also, the apparatus is arranged so that with the rear support section in its upper configuration and the main support frame being in its lower pivot configuration the boat support reference plane of the apparatus has a forward and downward slope relative to the ground support reference plane at an angle between about 0° to 10°. Further, the apparatus is arranged so that with the support section being in its upper configuration and the main support frame being in its upper pivot configuration, the boat support reference plane of the apparatus does not have a forward and downward slope relative to the ground support reference plane, and desirably has a forward and upward slope relative to the ground support reference plane.  
      Also, in a preferred form, the apparatus is arranged so that with the rear support section being in its lower configuration and the main support frame being in its upper pivot configuration the boat support reference plane of the apparatus is approximately parallel to the ground support reference plane, and desirably between 4° in an upward forward slant and 4° in an upward and rearward slant.  
      In the method of the present invention, the apparatus is provided as indicated above, and when operating as an apparatus to remove the boat from the body of water, the boat is located in the body of water over the rear main frame section with the rear support section in its upper configuration and the main support frame section in its lower pivot configuration. Then the rear support section is lowered to raise the rear main frame section to a higher elevation to raise the boat in the body of water. Then the apparatus is moved to carry the boat in a direction from the body of water.  
      Also in the method of the present invention, the boat can be launched from a land location into the body of water, and this is accomplished in substantially the reverse order of the method of retrieving the boat from the body of water. More specifically, the boat is located on the apparatus, and the apparatus is moved into the body of water. Then the rear main frame section is located at a lower ground elevation in the body of water, with the rear support section in its upper configuration and the main support frame in its lower pivot configuration so that the boat is substantially supported by a flotation force of the water.  
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       FIG. 1  is a side elevational view of the apparatus of the present invention in an operating position in a body of water with a boat positioned so as to be ready to be retrieved from the body of water;  
       FIG. 2  is a view similar to  FIG. 1 , but showing the rear main frame section being raised to partially lift the boat from the body of water;  
       FIG. 3  is a view similar to  FIGS. 1 and 2 , but showing only the hull of the boat, and showing the boat being carried out of the water;  
       FIGS. 4, 5 ,  6  and  7  are views showing the apparatus of the present invention in various configurations where the rear support section is in its upper configuration or lower configuration and the main frame is in its upper pivot configuration or lower configuration.  
       FIG. 8  is a top plan view of the apparatus of the present invention;  
       FIGS. 9   a  and  9   b  are two schematic top plan views showing only the rear support wheels and front steerable support wheels of the present invention and illustrating the  FIG. 9   a , the turning of the wheels, and in  9   b  the travel of the front wheels in a lateral direction;  
       FIG. 10   a  is a first view of an end portion of the one of the inflatable bunkers;  
       FIG. 10   b  is a second view of the end portion of the bunker, taken from the location which is 90° from the location in which  10   a  is being taken;  
       FIGS. 11   a  and  11   b  are elevational views showing one of two positioning members of the present invention, in two different positions;  
       FIG. 12   a  is a view partially in section, and is taken from a rear location, showing another side positioning device of the present invention;  
       FIG. 12   b  is a view of the positioning device of  FIG. 12   a , but taken from an upper location looking downwardly on the device of  FIG. 12   a;    
       FIG. 13  is a schematic top plan view illustrating the manner in which the apparatus of the present invention can be moved into a storage slot in a marina;  
       FIG. 14  is a side elevational view of a second embodiment of the present invention where the apparatus is being towed by a tractor; and  
       FIG. 15 . is a top plan view of the apparatus of  FIG. 14 .  
    
    
     DESCRIPTION OF THE PREFERRED EMBODIMENT  
      In  FIG. 1 , the boat transport/launching apparatus  10  of the present invention is shown with a boat  12 , which is positioned relative to the apparatus  10  to be carried out of a body of water. As will be discussed later herein, this apparatus  10  is able to carry the boat  12  into the water to launch the boat, carry the boat out of the body of water (as is shown in  FIGS. 2 and 3 ), and also to carry the boat over the land surface as in parking the boat in a location in a boat yard (as illustrated in  FIG. 13 ). For convenience of description, the apparatus  10  will simply be referred to as the “transport apparatus” in the following text.  
      It is believed that an understanding of the present invention will be better obtained by describing the invention in the following format. First, there will be a general description of the transport apparatus  10 , second a preliminary description of the basic operation of the present invention with reference to  FIGS. 1, 2  and  3 , third a more detailed description of the apparatus  10 , along with a discussion of various facets of the present invention, along with possible alternatives, and fourth a brief description of a second embodiment.  
      a) General Description of the Transport Apparatus  10 .  
      The apparatus  10  is particularly well adapted to be used for a boat having a hull configuration of a cabin cruiser of more or less conventional design as shown at  12 , and accordingly in the following description, the boat  12  which is being carried will be assumed to be such a cabin cruiser. However, it is to be understood that within the broader scope of the present invention, the apparatus  12  and the methods employed by the same would also be adapted to handle boats of other configurations.  
      There will first be an introductory description of the overall configuration of the boat  12  (i.e. a conventional cabin cruiser). This boat  12  comprises a hull  14  and a cabin structure  16  (shown only in  FIG. 1  for ease of illustration). The boat has a bow  18 , a stern  20 , and a hull bottom surface  22 . There is a center keel line  24 , and the bottom hull surface  22  comprises right and left bottom surface portions  26  on opposite sides of the keel line  24 . Further, each bottom surface portion  26  can be considered as having a rear bottom surface portion  28  and a forward bottom surface portion  30 . As is conventional with this type of cabin cruiser, the side walls  32  of the hull are spaced further from one another in the rear portion of the boat  12  and converge toward one another in the forward part of the boat  12  to meet at a front juncture line (a prow line  34 ). In like manner the bottom surface portions  26  become narrower and have a greater upward and lateral slant at its forward portion.  
      The transport apparatus  10  of the present invention comprises a main frame  40 , having a front end  42  and a rear end  44 , a rear wheeled support section  46 , a front wheeled support and steering section  48 , and an operating section  50 , having an operating platform  52  and a support rail  54  surrounding the platform  52 .  
      To describe the main frame  40  in more detail, the frame  40  has a front frame section  56 , and a rear frame section  58 , with these being joined to one another at a pivot location  60  which is approximately at the mid-length of the frame  40 . Also, in terms of function and structure the frame  40  can be considered as having (as seen in  FIG. 8  in plan view), an overall U-shaped configuration, comprising a forward frame portion  61  and right and left side frame portions  62  and  64 , respectively. Further, each of these side frame portions  62  and  64  has a forward side frame portion  66  and a rear side frame portion  68 , with each pair of front and rear side portions  66  and  68  being connected to one another by means of a respective pivot connection  70  at the pivot location  60 . The forward side frame portions  66  connect to one another by means of the forward frame portion  61  which is part of the front frame section  56 . Also the two forward side frame portions are part of the front frame section  56 , and the two rear side frame portions comprise the rear frame section  58 .  
      The frame  40  can be considered as having a longitudinal center axis  72  extending the length of the apparatus  10 , and also a transverse axis  74 , which for purposes of description will be considered being located at the pivot location  60 .  
      The frame  40  has a boat receiving region  76  extending substantially the entire length of the frame  40 , and comprising a rear entry portion  78 , a rear receiving region portion  80  located between the rear side frame sections  68 , and a forward receiving region portion  82  located between the forward side frame section  66 .  
      b) General Description of the Operation of the Apparatus  10 .  
      With the basic configuration of the transport apparatus  10  being given, we will now proceed to the next phase of this description, with reference to  FIGS. 1, 2  and  3  and describe the basic method of the present invention in taking the boat  12  out of the water.  
      Reference is now made to  FIG. 1 . Let us assume that the boat  12  is already floating in a body of water indicated at  86 , and having a water surface  88 , and it is now desired to take the boat out of the water at the location of a more or less conventional slanted launching ramp having an upwardly facing slanted ramp surface  90 . Initially, the transport apparatus  10  is backed downwardly along the ramp surface  90  into the water  86  with the rear wheeled support section  46  in a retracted position so that the rear end of the rear frame section  58  is at its lowermost position. Further, the front and rear frame sections  56  and  58  have been rotated relative to one another about the pivot location  60  so that the pivot location of the frame  40  is at its lowermost position so as to be proximate to the ramp surface  90 . With the transport apparatus  10  being in the configuration as shown in  FIG. 1 , the boat  12  is then operated to move the boat through the rear entry  78  and into the boat receiving region  76 . The boat shown in  FIGS. 1-3  is a relatively large boat  12  having an overall length as great as (or possibly even greater than) the entire frame  40 . As will be discussed hereinafter, the apparatus  10  is capable of handling a boat of larger length (as shown in the drawings), and also a boat of substantially shorter length.  
      The boat  12  is moved forward in the boat receiving region  76  until the rear portion of the boat is located in the rear receiving region portion  80  and the forward portion of the boat is located in the forward receiving region portion  82 . In this position, as shown in  FIG. 1 , the boat is still entirely supported by the flotation force of the water, or is substantially fully supported by the flotation force in the water.  
      The next step is shown in  FIG. 2 , and this is to lower the rear wheeled support section  46  so that the rear support wheels  92  of the rear wheeled section  46  are moved downwardly to lift the rear end of the frame  40  upwardly in a rotational movement about the front wheels  94  of the forward wheel support and steering section  48 . The front and rear frame sections  56  and  58  are held in a fixed angular position during this operation as the entire frame  40  is lifted. Alternatively, there can be accomplished with possibly a moderate adjustment in the angular position of the two frame sections  56  and  58  for proper clearance or other reasons.  
      In  FIG. 2 , there is shown a horizontal line indicating the level of the water surface at  88  with the boat  12  in the raised position in  FIG. 2 . Also, there is shown in a broken line at  88   a  the water level relative to the boat when the boat was still afloat in the location of  FIG. 1 . In the position of  FIG. 2 , a bottom part of the boat hull  14  is still in the water to provide a certain amount of a buoyancy force, but there is sufficient proportion of the weight of the boat pressing against (and being supported by) the rear frame portion  58  so that the transport apparatus  10  in moving out of the water, is able to move the boat  12  out of the water. Alternatively the boat  12  could be lifted totally out of the water in reaching the position of  FIG. 2 , but there would normally not be any advantage in doing so initially.  
      In  FIG. 3 , the boat  12  has been moved up the ramp  90  and completely out of the water, and the rear support wheels  92  are positioned on the more forward location of the sloping ramp  90 . The front wheels  94  are shown as being on a level ground surface  96 . Further, it can be seen that the alignment of the forward and rear frame portions  56  and  58  has been changed moderately by relative rotation about the pivot location  60 , and this could be done, for example, to obtain sufficient clearance from the ground surface as the transport apparatus  10  is moving from a slanted surface to a more level surface.  
      From the above description, it becomes evident that to launch the boat back into the water, the reverse of the above sequence shown in  FIGS. 1, 2  and  3  is accomplished. More specifically, the apparatus  10  and the boat  12  are moved to the location of  FIG. 3 , and the apparatus  10  moved rearwardly to the launch location of  FIG. 2 . From the launch location of  FIG. 2 , the rear wheeled support section  46  has the rear wheels  92  raised to lower the rear portion of the main frame  40 , thus putting the boat in the floating position of  FIG. 1 .  
      c) More Detailed Description of the Transport Apparatus  10 .  
      To describe the various components of the apparatus  10  in more detail, we will begin first by looking at the rear wheeled support section  48 . It can be seen in  FIG. 8  that the rear wheel support section  46  comprises right and left rear wheel support sections  98  and  100 , each of which comprises its related rear wheel  92  mounted to a related support arm  102  which in turn is pivotally connected at  104  at its forward end to its related rear side frame section  68 . There is an actuator  106  (e.g. a piston and cylinder hydraulic) connected between its related arm  102  and its related rear frame portion  68  to extend in a manner to lower each wheel  92  or to contract to raise the wheel  92 . It is evident that there could be other actuators in the form of one of a wide variety of mechanisms or devices to accomplish this lifting or lowering function, such as lifting jacks, extendable and retractable linkages, articulated lifting mechanisms, etc. Since such alternative methods are well know to those having reasonable skill in the mechanical arts, these will not be described in detail herein.  
      Attention is now directed to the forward wheel support steering section  48 . The two front wheels  94  are spaced laterally from one another at the front end of the frame  40 , and each wheel  94  is mounted for rotation about its own vertical steering axis  108  which is shown schematically in  FIG. 8  as being immediately over the center location of its related wheel  94 . Thus, as can be seen in the schematic showings of  FIGS. 9A and 9B , the two front wheels  94  can be rotated in either direction a full ninety degrees so that the alignment of the direction of the rolling path of the wheel is at ninety degrees to the longitudinal axis  72 , as illustrated by the arrows  110  shown in  FIG. 9A . In the position of  FIG. 9B , the wheels  94  are aligned so that movement of the forward portion of the apparatus  12  is in a transverse direction ninety degree to the longitudinal axis  72 , about a rear center of rotation indicated at  112  which is located in transverse alignment with the centers of rotation of the rear wheels  92 . The significance of this in enabling the apparatus  12  to move very effectively, for example in a boat yard, will be discussed later in this text with reference to  FIG. 13 .  
      The steering of the front wheels  94  can be accomplished in a conventional manner by an operator positioned on the operating platform  52 . Further, the front wheels  94  can be driven by suitable individual motors (e.g. hydraulic or electric motors), and since this can be done in a conventional manner, this will not be described in detail herein. Further, while the vertical axis of rotation  108  for each front wheel  94  is shown as being directly over the wheel  94 , it could be offset slightly from its wheel  94  and function properly in the present invention. For example, there could be a vertical rotatably mounted support post offset from its wheel  94  and connecting to it wheel  94  through a suitable drive axle.  
      Let us now turn our attention to the main frame  40 , and begin by discussing the forward frame section  56 . The two right and left forward frame portions  66  that make up the forward frame section  56  are, or may be, identical, and each comprises an outer longitudinal frame member  114  and an inner longitudinal frame member  116 . The forward ends of the outer frame members  114  are connected to one another by a cross member  118  at an upper location on the front frame section  71 . It can be seen by observing, for example, any one of  FIGS. 4-7 , and also observing  FIG. 8 , that the alignment of the two frame members  114  and  116  is such that their rear ends are at the same transverse location at the same level at the rear pivot location  60 , and that the two outer frame members  114  extend parallel with one another to the front location at an upper level of the forward frame section  71 . On the other hand, the inner frame members  116  extend forwardly and converge at a slight angle inwardly in a forward direction, and also extend at a moderate downward angle relative to the orientation of the outer frame members  114 . This forms a truss like structure to contribute to the overall structural strength of the entire front frame portion  56 , and also this arrangement provides the proper clearance in the forward receiving region portion  82 .  
      It is to be understood, of course, that there is proper structural bracing between the inner and outer frame members  114  and  116  as well as for the cross member  118 , and at least some of this structural bracing is illustrated in  FIGS. 4-7  and also in  FIG. 8 . For example, there is a pair of diagonal braces  120  extending between related frame members  114  and  116 , and also diagonal braces at  122  and  124  extending between the forward portions of the inner frame members  116  that extend somewhat forwardly from the location of the front wheels  94  and of the cross member  118 . In addition, there could be, for example, diagonal bracing extending between the central part of the cross member  118  in a rearward and horizontally outward direction to connect to the outer frame members  114  near the forward ends thereof. Also, it is to be understood that the mounting structure for the front wheels  94  would be such so that there would be proper structural bracing and also to make the proper connection with the front frame portion  56  so that the weight loads would be properly transmitted from the frame  40  through the structure to the front ground wheels  94 .  
      With reference to  FIG. 8 , the rear ends of the two forward frame members  114  and  116  join to one another at the pivot connection  70 , this pivot connection actually being made by the two separate pivot connections  126  and  128  that are transversely aligned with one another. There are two positioning actuators (i.e. hydraulic cylinder and piston members  130 ), each connecting by one end  132  to a cross strut between the frame members  114  and  116 , and the other end connecting at  134  to a forward end of a positioning arm  136  that is connected by a cross brace  138  to the forward end of its rear side frame section  68 . Thus, extension and retraction of the two cylinder and piston members  130  causes rotation of the positioning arm  136 , thus causing relative rotation of the forward and rear main frame portions  56  and  58 .  
      It is obvious that there could be other mechanisms, actuators, linkages and devices to provide relative rotation between the frame sections  56  and  58 , such as crank arms rotary actuators, gear drives, etc. Since these are numerous and well known to those of reasonable skill in the mechanical arts, these will not be described in detail herein.  
      To describe now the rear frame section  58  in more detail, reference is again made to  FIG. 8 . It can be seen that the rear frame section  58  actually comprises the aforementioned right and left rear frame portions  68 . It can also be seen from observing  FIG. 8  that these two rear frame portions  68  can each rotate independently of one another about the pivot connections  126  ad  128 . Each of these rear frame portions  68  comprises outer and inner frame members  144  and  146  interconnected by suitable cross braces some of which are indicated at  148 .  
      There are two rear guide members  150  and two forward guide members  151  (boat positioning members) which are located at side portions of the rear frame portion  58 . The two rear guide members  150  are positioned at the rear end of the rear frame portion  58 , and these are shown in elevational view in  FIGS. 11A and 11B . Each forward guide member  151  (shown in  FIGS. 12A and 12B ) comprises a cushioned roller  152  mounted to the top end of a right angle mounting arm  154 , with this arm  154  having an upright arm portion  156  and a lateral end arm portion  158  with the inner end of the arm portion  158  being rotatably connected to a rotary mounting section  160  that is in turn connected to the related outer frame member  144 . A spring positioning member is provided, as shown at  161  to urge the cushion member  152  toward the longitudinal center axis  72 .  
      One of the two rear guide members  150  is shown in  FIGS. 11A and 11B . and it can be seen that in like manner this comprises a cushion roller  162  connected to a right angle member  164  which in turn is pivotally connected at  166  at the rear end of the inner frame member  146 . The pivot connection  166  is aligned longitudinally, and there is a positioning spring  168  (shown only in  FIG. 11A ) positioned beneath the horizontal portion of the right angle arm  164  to urge the arm  164  inwardly. Also, the pivot connection of the arm  164  is to a sleeve member  170  which has a positioning pin  172  which can be mounted in a selected one of the positioning openings  174  and a mounting member  176 . Thus, the lateral positioning of the two guide members  150  can be adjusted laterally by proper positioning of the sleeve member  170 .  
      In like manner forward positioning members  178  can be provided and be constructed in a manner similar to the guide members  150  and  151 .  
      A significant feature of the present invention will now be described with reference to  FIGS. 8, 10A ,  10 B, and  12 A. First, with reference to  FIG. 8 , there are two substantially identical inflated bunker members  180 , each extending the entire length of its related frame member  146 . One of the inflatable bunker members is shown in the cross sectional view of  FIG. 12A , where it can be seen that the frame member  146  is provided with an elongate cradle  182  which has a uniform cross section extending the length of the frame member  146 . This cradle  182  can be made as a metal extrusion, and defines an upwardly curved concave cradle surface  184 . Each inflatable bunker member can be secured in the cradle  182  in a suitable manner such as bonding, mechanical fasteners, etc.  
      Reference is now made to  FIGS. 10A and 10B  which illustrate the end closure portion of the inflatable bunker  180 . It can be seen that the end portion  186  is flattened, and there is positioned above and below the flattened portion  186  clamping plates  188  held together by a plurality of spaced nut and bolt connections  190 . A suitable sealant can be placed at the end clamping location to ensure that there is an airtight seal. Suitable inflating and venting means can be supplied in the way of a typical air valve so that the proper pressure can be maintained in each of the inflatable bunkers  180 . It has been found that these inflatable bunkers  180  provide a number of advantages. First, the cushioning action of each of the bunkers  180  is such so that the compressed upper surface areas of each bunker  180  are maintained at the same air pressure throughout. Thus, each unit of the contact area of the bunker  180  exerts a substantially uniform pressure against the engaged portion of the bottom surface of the hull  14 . Also, as the transport apparatus  10  is moved over a ground surface, any impacts created by holes or bumps in the ground surface are substantially alleviated by the cushioning effect of these inflatable bunkers  180 .  
      To now discuss another facet of the present invention, reference is made to  FIG. 13  which is a rather schematic view showing the outline of the transport apparatus  10  which is positioned in a corridor  190 , this corridor is bounded on two sides  192  and  194  by parking slots or stalls for boats and/or trailers or supports. In the schematic drawing in  FIG. 13  the transport apparatus  10  is shown as an elongate rectangle  10 , and the trailer is moving in the direction indicated at  195  with the forward end (i.e. the operating end) being shown at  50 . It can be seen that the transport apparatus  10  can be turned in a path of travel indicated in the several broken line representations of the apparatus  10  location at  10   a ,  10   b ,  10   c  and  10   d  so that it can be placed into one of the slots indicated at  196 . Further, it can be seen that the spacing of the two corridor sides  192  and  194  could be nearly the same as (or just slightly greater than) the total operating length of the transparent apparatus  10  plus the portion of the boat that may be overhanging the back end of the apparatus  10 .  
      To discuss other features of the present invention, reference is now made to  FIG. 2 . In a conventional cabin cruiser, such as shown at  12 , the center of gravity would be at a position moderately to the rear of a longitudinal center location of the cruiser. To explain this further, the total dimension from the bow to the stem of the cruiser  12  is in  FIG. 2  shown by the line  200 . Let us assume that the distance from the stern  20  to the bow  18  is 100%. In that instance, the center of gravity would usually be at the 40% location from the stem  20 , indicated at  202 . Now we turn our attention to the total length dimension between the center of the rear wheels  92  and the center of the front wheels  94 , these being the two support locations, and this dimension is shown at  204 . Let us assume that this dimension  204  is also considered to be 100%, with the location of the center of the rear wheels  92  being 0% and the center of the front wheels  94  being 100%. The pivot location  60  would be approximately half way between the two end support locations of the wheels  92  and  94 , and in one preferred embodiment where the distance between the center of the front and rear wheels  92  and  94  is forty two feet, this pivot location  60  is at the 53% location measured from the center of the rear wheels  92 .  
      In this particular embodiment of the present invention, the distance between the center of the front wheels  94  to the pivot location  60  is 19.5 feet, and the distance from the center of the rear wheels  92  to the pivot location  60  is 22 feet. These relative dimensions could be adjusted for various reasons, depending upon the size and type of boat which is being carried by the transport apparatus  10 , the configuration of the boat ramp which is used, etc. In general, the pivot location  60  between the front and rear support locations of the wheels  92  and  94  would be between the 50-55% location from the stem  20 , with this percentage value possibly being as high as up to 60% or up to possibly 65% or conceivably as high as about 70% or 75%. An upper reasonable limit would be no greater than a limit having the ratio length of the rear distance (the center of the rear wheels to the pivot location  60 ) to the forward distance (from the pivot location  60  to the center of the front wheels) no greater than about three to one. The distance from the center of the rear wheels  92  to the pivot location  60  would possibly be at the 45% distance or even 40% distance from the stem  20 , with the reasonable lower limit being one-third of the total distance from the center of rear wheels  92  to the center of the front support wheels  94 .  
      To relate this analysis to the operation of the present invention, it can be seen that with a relatively large boat  12  resting on the main frame  40 , the center of gravity at  202  is positioned on the rear frame portion  58  at a location intermediate the pivot axis  60  and the rear wheels  92 . Thus, the boat is supported by its rear portion resting on the inflatable bunkers  180 , and the forward portion of the boat  12  extends into the forward receiving region  82  between the forward side frame members  66 .  
      If a smaller boat is being either launched or removed from the water by the transport apparatus  10 , then the total length of the boat could possibly be accommodated entirely by the rear frame portion  58 . Thus it can be seen that the arrangement of the transport apparatus  10  is such that relative to overall length of the entire transport apparatus  10 , it is possible that much larger boats (which heretofore have been removed from and placed into the water by means of a hoist) could be handled, as well as the smaller boats. Also, as indicated previously, this can be done so that a relatively large boat  12  can be maneuvered in a relatively small space and moved into a storage slot in a marina.  
      To explore yet another facet of the present invention, reference is made to  FIGS. 4-7 . It can be seen that the rear frame portion  58  has what could be termed a boat support plane indicated by the numeral  210 . In this particular configuration, the boat support plane would be the planar alignment of the support surface of the bunker members  180 . For convenience of illustration, in  FIGS. 4-7 , this support plane  210  has been shown as extending over the top surface of the inner rear frame members  146 . Related to this analysis is the ground support alignment plane  212  of the underlying ground support plane relative to the support plane of the rear frame portion  58 . Thus in  FIGS. 4-7  the ground support reference plane  212  is defined by the ground engaging portions of the rear and front wheels  92  and  94 . This ground support reference plane  212  is defined by the locations of the ground engaging support at the front and rear ends of the apparatus.  
      Reference is first made to  FIG. 4 , where the pivot location  60  is at its lowermost position, and the rear wheels  92  are in the retracted position. It can be seen that the alignment plane  210  has a very slight downward and forward slope, and the angular orientation relative to the support surface  212  is at an angle of about four degrees, indicated at  214 . In  FIG. 5 , the rear wheels  92  have been moved downwardly to their lowermost position, and the angular orientation of the front and rear frame sections  58  and  56  remains the same. In this instance, the slope of the support plane  210  relative to the ground surface  212  is about six degrees, as indicated at  216 .  
      In  FIG. 6 , the forward and rear frame sections  56  and  58  have been rotated relative to one another so as to raise the pivot location  60 , and the orientation of the support plane  210  is nearly parallel to the lower support surface  212 .  
      In  FIG. 7 , the orientation of the front and rear frame portions  56  and  58  remain the same as in  FIG. 6 , but the rear wheels  92  have been retracted. In this instance, the support plane  210  of the rear frame portion  58  is at a forward and upward slope of about two degrees, as indicated at  218 .  
      To comment further on the above observations made with regard to the angular disposition of the rear support frame portion  58 , it should be noted that in the configurations of  FIG. 4  and  FIG. 5  correspond to the positions shown in  FIGS. 1 and 2 , respectively, where the rear frame portion  58  would normally be positioned on the sloping ramp and in the water. Further, in the configuration of  FIG. 6  this would be a usual configuration when the transport apparatus is being moved from the ramp onto level ground (as shown in  FIG. 3 ) or entirely on a ground surface that is not beneath the water. The configuration of  FIG. 7 , could be used in a variety of situations, one of which is where the downward and rearward slope is desired where the frame portion  58  is on a ground surface when it is desired to drain the boat hull  14  of water.  
      Obviously, these various alignment relationships could vary from the values give above, and this could depend on the slope of the ramp surface and the slope and contour of the ground in the marina. With regard to the alignment in the configuration alignment angle in the operating arrangement of  FIG. 4 , this could be at an angle greater than zero degrees or greater than two degrees, and on the higher side could, depending upon the situation, be six degrees, eight degrees or ten degrees.  
      In the configuration of  FIG. 5  the angular relationships discussed above with reference to  FIG. 4  would apply, but the range could be greater depending on the slope of the ramp.  
      With regard to the configuration of  FIG. 6 , where the support plan  210  is nearly parallel to the support surface  212 , this angle could also vary by one degree increments up to conceivably ten degrees (e.g. one degree, two degrees . . . ten degrees) either upwardly or downwardly. In general, there would not be any great advantage in going up to these limits, but there could be particular situations where there would be advantages.  
      With regard to the operating configuration shown in  FIG. 7 , the two degree downward and rearward slope could obviously be decreased slightly, or it could be raised by various increments, such as one degree increments from three degrees, four degrees . . . up to ten degrees. This could occur for example, if the underlying ground surface is sloped to some extent. Alternatively, it may be that for certain boats the angle needs to be somewhat higher to cause proper drainage of the water in the hull.  
      d) Second Embodiment of the Present Invention.  
      Reference is made to  FIGS. 14 and 15  which show a second embodiment of the present invention. Components of this second embodiment which are the same as, or similar to, components of the first embodiment will be given like numerical designations, with an “a” suffix distinguishing those of the second embodiment.  
      This embodiment differs from the first embodiment in that the operating section  50  with the platform  52  has been removed and also the front wheel support section  48  has been removed. As in the first embodiment, the transport apparatus  10   a  comprises the main frame  40   a  with the rear wheeled support section  46   a . The main frame  40   a  in turn comprises the front and rear main frame portions  56   a  and  58   a , with a pivot location  60   a . In addition, the main frame comprises the right and left side frame section  62  and  64 . Also, there is the boat receiving regions  76   a  with a rear entry  78   a  and the rear and front region portions  80   a  and  82   a , with the front region portion  80   a  extending into the forward frame section  56   a.    
      In place of the front wheel section  48  of the first embodiment, there is provided a front support  220  extending downwardly from the forward end of the main frame  40   a . This support  220  can simply be posts, or alternatively, these could also comprise wheels, such as the wheels  94  of the first embodiment, along with power for the wheels and also a mechanism for turning the wheels. These would be used in the event that the transport apparatus  10   a  would be moved independently of any towing vehicle.  
      In addition, there is a forward extension  222  fixedly attached to the front end of the main frame  40   a , and this has a fifth wheel connection at  224 . Thus, this could be carried by a tractor, as shown at  226 , or another towing vehicle. Also, the forward part the main frame  40   a  could be provided with front jacks or other vertical actuators to raise or lower the front end of the main frame  40   a  to better enable the connection with a towing vehicle to be made.  
      It is believed the operation of this second embodiment is evident from the prior discussion of the operation of the first embodiment, so this will not be repeated at this location in this text.  
      It is to be recognized that various modifications could be made in the present invention without departing from the basic teachings thereof. For example, the specific construction of the main frame  40  and  40   a  (in the second embodiment) could have a different arrangement of the members such as the specific longitudinal beams, the cross bracing, etc. Since it is well within the skill of a designer of such truss like structures, there is no need to discuss the selections of the many types of beam and beam truss configurations that could be used. Also, with regard to the rear wheel support sections  46  and  46   a , various actuators and devices for lifting and lowering the rear end could be used. Since the many linkages and actuators of various types are well known to those having skill in designing such mechanical devices, there is no need to list the various possibilities, such as crank arms, toggle devices, rotary actuators, scissors linkages, etc.  
      The main components of the present invention are defined in the claims submitted herewith and it is obvious that such modifications could be made within the scope of these claims.