Patent Publication Number: US-7707959-B2

Title: Boat with sponson

Description:
CROSS-REFERENCE TO RELATED APPLICATION 
   The present application claims priority under 35 U.S.C. §119 to Japanese Patent Application No. 2005-069161, filed Mar. 11, 2005, the entire contents of which are hereby incorporated by reference. 
   BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a boat provided with a sponson section at the outer periphery of the hull, and a sponson section at the outer periphery of the deck, with the respective sponson sections bonded together to form a boat body. 
   2. Description of Background Art 
   Small boats exist where a water jet pump is fitted to a rear part of a boat body, with water then being sucked in from the boat bottom as a result of an engine driving a water jet pump, and the sucked-in water then being blasted to the rear so as to cause the small boat to glide. 
   The small-type boat is equipped with a front hood at an upper end of the deck with a gap formed between the front hood and the deck. Air from this gap is then taken in to within the boat body, and the air that is taken in is guided through the engine (for example, refer to Japanese Patent Laid-Open Publication No 2003-137188. 
   Here, it is necessary to ensure a gap for gathering air between the front hood and the deck, and there is the fear that sea water or water may permeate through this gap. Here, the small boat of Japanese Patent Laid-Open Publication No 2003-137188 has a labyrinth structure for the gap between the front hood and the deck. By adopting a labyrinth structure for the gap between the front hood and the deck, it is possible to only extract air from the gap and prevent sea water and water from permeating. 
     FIG. 6  is a view illustrating a gliding state of a small boat of the related art. An end  101   a  of the boat body  101  collides with a wave  102  so as to generate spray when the small boat  100  is gliding. 
   The large amount of spray generated then rises along the hull  103  as shown by arrow a. It can be considered that the rising spray will pass over the hull  103  so as to splash the side of the deck  104  as shown by the arrow b. 
   Even in the event that the spray splashes the side of the deck  104 , it is necessary to prevent the spray from permeating to within the boat body  101  using the labyrinth structure between the deck  104  and front ford  105 . Because of this, even in cases where the end  101   a  of the boat body  101  collides with the wave  102  so as to generate spray, it is preferable that the spray created does not splash the side of the deck  104 . 
   SUMMARY AND OBJECTS OF THE INVENTION 
   It is therefore the object of the present invention to provide a small boat capable of preventing splashing of spray to the deck side. 
   According to a first aspect of the present invention, a small boat is provided with a hull sponson at an outer periphery of a hull in order to attach a deck constituting an upper part of a boat body to the hull constituting a lower part of the boat body, and a deck sponson provided at an outer periphery of the deck, with the deck sponson being overlaid on the hull sponson and bonded. Spray generated as a result of the boat body colliding with waves is prevented from splashing the deck side while the boat is gliding by making an extent of projection of a member on the side of the front section of the boat body larger than another member. 
   The extent of projection of the member on the side of the front section of the boat body, of the hull sponson and the deck sponson, is made larger than for other parts. It is also possible for spray generated as a result of the end of the boat body colliding with waves to collide with the hull sponson for which the extent of projection is larger and the deck sponson. As a result, it is possible to prevent spray from splashing the deck side by utilizing existing hull sponsons and deck sponsons. 
   According to a second aspect of the present invention, a small boat is provided with a hull sponson at an outer periphery of a hull in order to attach a deck constituting an upper part of a boat body to the hull constituting a lower part of the boat body, and a deck sponson provided at an outer periphery of the deck. The deck sponson is overlaid on the hull sponson and bonded. The hull sponson and deck sponson are formed with a substantially L-shaped cross-section using a horizontal sponson and a downwardly extending section. Thus it is possible to prevent spray generated as a result of the boat body colliding with waves splash the deck side while the boat body is gliding by making the height of the portion on the side of the front section of the boat body, of the downwardly extending section of the hull sponson and the deck sponson, larger than another member. 
   It is also possible to ensure that spray falls downwards in a substantially more reliable manner using a downwardly extending section by making the height of the member on the side of the end of the boat body, of the downwardly extending section of the hull sponson and deck sponson, larger than the other member. As a result, it is possible to reliably prevent the spray from splashing at the side of the deck. 
   According to the first aspect of the present invention, it is possible to prevent spray from splashing onto the side of the deck by making the extent of projection of the member on the side of the end of the boat body, of the hull sponson and the deck sponson, larger than the other member. 
   According to the second aspect of the present invention, it is possible to reliably prevent spray from splashing onto the side of the deck by making the height of the member on the side of the end of the boat body, of the downwardly extending section of the hull sponson and the deck sponson, larger than the other member. 
   Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
     The present invention will become more fully understood from the detailed description given hereinbelow and the accompanying drawings which are given by way of illustration only, and thus are not limitative of the present invention, and wherein: 
       FIG. 1  is a side view of a small boat (first embodiment) of the present invention; 
       FIG. 2  is a perspective view showing the state of the small boat of a first embodiment when viewed from below; 
       FIG. 3(   a ) is a cross-sectional view along  3   a - 3   a  of  FIG. 2 , and  FIG. 3(   b ) is a cross-sectional view showing the essential parts of the small boat of the first embodiment in an exploded state; 
       FIGS. 4(   a ) and  4 ( b ) are views describing examples of guarding the small boat from spray of the first embodiment; 
       FIG. 5  is a cross-sectional view showing the essential parts of a small boat (of a second embodiment) of the present invention; and 
       FIG. 6  is a view illustrating a gliding state of a small boat of the related art. 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   The following is a description of preferred embodiments based on the appended drawings. Here, “front”, “rear”, “left” and “right” are such that Fr is the front side, Rr is the rear side, L is the left side, and R is the right side. 
     FIG. 1  is a side view of a small boat (first embodiment) of the present invention. A water jet propulsion boat is a small boat  10  equipped with a fuel tank  12  at a front section  11   a  of a boat body  11 , an engine  13  is provided to the rear of this fuel tank  12 , a pump chamber  14  is provided to the rear of the engine  13 , a pump chamber  14  is provided to the rear of the engine  13 , a water jet pump  15  is provided at this pump chamber  14 , a water muffler  17  is fitted at the intake side of the exhaust pipe  16  at the engine  13  so that the exhaust side of an exhaust pipe  16  faces the inside of the pump chamber  14 , at the middle of the exhaust pipe  16 , handlebars  22  are fitted above the fuel tank  12 , and a sheet  23  is fitted to the rear of the handlebars  22 . 
   A hull  18  constituting the lower part of the boat body  11  is covered by a deck  19  constituting the upper part of the boat  11 . A spray guard  35  is formed by utilizing a connection section connecting the deck  19  to the hull  18 . 
   The water jet pump  15  is such that a housing  26  extends from an intake opening  25  of a boat bottom  24  to the rear, an impeller is fitted in a freely rotatable manner within the housing  26 , and a propeller shaft  28  is provided at the impeller  27 . The propeller shaft  28  is coupled to the drive shaft  31  of the engine  13  via the coupling joint  30 . 
   According to the water jet pump  15 , as a result of the impeller  27  rotating due to being driven by the engine  13 , water taken in from the intake opening  25  of the boat bottom  24  is blasted to the rear of the boat body  11  from a steering nozzle (steering nozzle)  33  via a rear nozzle  32  of the housing  26 . As a result, the small boat  10  is propelled (glides) in an advancing direction. 
   When the small boat  10  advances to the rear, a reverse bucket  34  above the steering nozzle  33  moves to a position of advancement to the rear to the rear of the steering nozzle  33 . As a result, water spurted to the rear from the steering nozzle  33  is guided to the front of the boat body  11  by the reverse bucket  34 , and the small boat  10  is made to advance rearwards by the guided spurting water. 
     FIG. 2  is a perspective view of a forward end  18   b  of the hull  18  showing the state of the small boat of a first embodiment when viewed from below. The spray guard  35  is formed along an outer periphery  11   b  of the boat body  11 . The spray guard  35  has a spray receiving section  36  formed along the outer periphery  11   b  of the boat body  11  and has a spray returning section  37  extending in a downward direction from an end of the spray receiving section  36 . As can be seen in  FIG. 2 ,  3 ( a ), and  3 ( b ), hull  18  is formed with several distinct shapes between the hull sponson  41  and the hull bottom  24 , including a first portion (upper end outer periphery)  18   a  extending substantially vertically and downwardly from a inner edge of the hull sponson  41 , a second portion  18   c  extending substantially horizontally and inwardly with respect to a lower end of the upper end outer periphery, a downwardly facing concave groove  18   d  formed inwardly with respect to the second portion  18   c , and first and second downward sloping portions  18   e ,  18   f  extending downwardly and inwardly from an inner side of the concave groove  18   d , the second downward sloping portion  18   f  joining the hull bottom  24 . 
   The spray guard  35  results from the deck sponson  42  being overlapped with the hull sponson  41  from above. The hull sponson  41  is a member projecting to outside along the upper end outer periphery (outer periphery)  18   a  of the hull  18 . The deck sponson  42  is a member projecting to the outside along the outside (outer periphery)  19   a  (refer to  FIGS. 3(   a ) and  3 ( b )) of the lower end of the deck  19 . In the following, a detailed description is given of the spray guard  35 . 
     FIG. 3(   a ) is a cross-sectional view along  3   a - 3   a  of  FIG. 2 , and  FIG. 3(   b ) is a cross-sectional view showing the essential parts of the small boat of the first embodiment in an exploded state. The hull sponson  41  is formed with a substantially L-shaped cross-section by a horizontal sponson  44  and a downwardly extending section  45 . The horizontal sponson  44  projects substantially horizontally from the outer periphery  18   a  of the upper part of the hull  18  in a direction to outside. The extent of projection of the horizontal sponson  44  is L. The downwardly extending section  45  extends in a state of bending downwards from the outer end of the horizontal sponson  44 . Height H of the downwardly extending section  45  is H 1 . In addition,  FIGS. 3(   a ),  3 ( b ), and  5  illustrate the second portion  81   c  of hull  18  that is substantially horizontal and extends rearwardly and inwardly toward a central portion of the boat from a lower end of the upper end outer periphery  18   a  of the hull  18 . 
   The deck sponson  42  is formed with a substantially L-shaped cross-section by a horizontal sponson  47  and a downwardly extending section  48 . The horizontal sponson  47  extends in a substantially parallel manner with respect to the horizontal sponson  44  from the outer periphery  19   a  of the lower part of the deck  19 . The downwardly extending section  48  extends downwards in a direction parallel to the downwardly extending section  45  from the outer end of the horizontal sponson  47 . 
   The deck sponson  42  is formed to be substantially round and large with respect to the hull sponson  41 . As a result, it is possible to overlap the hull sponson  41  with the deck sponson  42  from above. 
   The deck sponson  42  is overlaid so as to cover the parallel sponson  41 . The lower surface of the horizontal sponson  47  is bonded to the upper surface of the horizontal sponson  44  using adhesive (not shown), and the inner surface of the downwardly extending section  48  is bonded to the outer surface of the downwardly extending section  45  using adhesive (not shown). The deck sponson  42  is bonded to the hull sponson  41 , so that the boat body  11  is formed from the hull  18  and deck  19 . 
   Further, the deck sponson  42  is bonded to the hull sponson  41  so as to form the spray guard  35  from the hull sponson  41  and the deck sponson  42 . The spray guard  35  is such that the spray receiving section  36  is formed along the outer periphery  11   b  of the boat body  11  from the horizontal sponsons  44 ,  47  and the spray returning section  37  is formed from the downwardly extending sections  45 ,  48 . The spray receiving section  36  projects by the amount L and the spray returning section  37  has a height H of H 1 . Also,  FIGS. 2 ,  3 ( a ),  3 ( b ), and  4 ( b ) illustrate lower edge  45   e  of downwardly extending section  45  of the hull sponson  41  being flush with lower edge  48   e  of downwardly extending section  48  of the deck sponson  42 . 
   At an end  35   a , the spray guard  35  is such that the end of the spray receiving section  36  projects substantially from the outer periphery  11   b  as a result of making the extent of projection L of the spray receiving section  36  large at L 1 . 
   Returning to  FIG. 2 , a description is given of the extent of projection L of the spray guard  35 . The spray guard  35  is formed in such a manner that the extent of projection L of the end  35   a  is formed to a maximum L 1 , with the extent of projection L gradually becoming smaller from the end  35   a  to left and right portions  35   b ,  35   c  so as to become L 2 , and with the extent of projection L to the rear of the left and right portions  35   b ,  35   c  being formed so as to be fixed at L 2 . 
   As a result, the spray guard  35  is formed in such a manner that the extent of projection L of a member (i.e. member  38  on the side of the front section  11   a  of the boat body  11 ) from the end  35   a  to the left and right portions  35   b ,  35   c  is larger than other members  39 . 
   Here, the dimensions of the extent of projection L 2  of the other member  39 , of the spray guard  35  and the dimensions of the height H 1  (refer to  FIG. 3 ) of the spray guard  35  are decided based on the bonding strength demanded by the hull  18  and the deck  19 . 
   The reason the extent of projection L of the member  38  on the side of the front section  11   a  of the boat body  11  is formed so as to be large is as described below. Namely, the end (end section of the boat body) of the hull  18  collides with waves so as to create spray while the small boat  10  is gliding. The spray is therefore dispersed upwards by forming the extent of projection L of the member  38  of the front section  11   a  of the boat body  11  to be large, i.e. spray to the deck side is effectively suppressed. 
   In the above description, the extent of projection of the member  38  on the side of the front section  11   a  of the boat body  11  of the hull sponson  41  and the deck sponson  42  is formed to be large. Thus, it is possible to form the extent of projection L of the portion  38  of the front section  11   a  of the boat body  11  of the spray guard  35  to be large. As a result, spray generated as a result of the end  18   b  of the hull  18  colliding with the water when the boat body  11  is gliding is capable of colliding with the spray guard  35 . 
   As a result, it is possible to utilize the hull sponson  41  and the deck sponson  42  as a spray guard  35  simply by making the extent of projection L of the member  38  on the side of the front section  11   a  of the boat body  11  of the existing hull sponson and deck sponson large. It is therefore possible to prevent spray from splashing to the side of the deck  19  by providing the spray guard  35 . 
   Next, a description is given of the operation of the spray guard  35  based on  FIGS. 4  ( a ) and  4 ( b ).  FIG. 4(   a ) and  FIG. 4(   b ) are views describing examples of guarding the small boat from spray of the first embodiment. In  FIG. 4(   a ), an end  18   b  of the hull  18  collides with a wave  55  so as to generate spray  56 . The large amount of spray  56  generated then rises along the hull  18  as shown by arrow A. 
   In  FIG. 4(   b ), the spray  56  rises as shown by arrow B along the hull  18 . The rising spray  56  collides with the spray receiving section  36  of the spray guard  35 . Spray  56  colliding with the spray receiving section  36  then collides with the spray returning section  37 , and falls downwards as shown by arrow C. As a result, it is possible to prevent the spray  56  from splashing at the side of the deck  19 . 
   Next, a description is given of a second embodiment. In the second embodiment, portions that are the same or analogous to those of the small boat  19  in the first embodiment are given the same numerals and are not described.  FIG. 5  is a cross-sectional view showing the essential parts of a small boat (of a second embodiment) of the present invention. With a small boat  60  of the second embodiment, the spray guard  35  of the first embodiment is replaced with a spray guard  61 , with other aspects of the configuration being the same as for the first embodiment. The spray guard  61  is such that the spray returning section  62  is given a height H of H 2  that is higher than the height H 1  of the first embodiment. 
   Specifically, the spray guard  61  is such that the height H of an end  61   a  is formed to a maximum H 2 , with the height H from the end  61   a  to the left and right portions (i.e. portions corresponding to the left and right portions  35   b ,  35   c  of the first embodiment) gradually becoming smaller so as to become a height H 1  (refer to  FIG. 3 ), and with the height H to the rear of the left and right portions being fixed at H 1 .  FIG. 5  also illustrates lower edge  45   e  of downwardly extending section  45  of the hull sponson  41  being flush with lower edge  48   e  of downwardly extending section  48  of the deck sponson  42 . 
   As a result, the spray guard  61  is formed in such a manner that the height H of a member (i.e. member  38  on the side of the front section  11   a  of the boat body  11 ) from the end  61   a  to the left and right portions is larger than other members  39 . The member  38  of the front section  11   a  of the boat body  11  and another member  39  are shown in  FIG. 2 . 
   According to the spray guard  61  of the second embodiment, by making the height H of the spray returning section  62  large at the member  38  on the side of the front section  11   a  of the boat body  11 , it is possible for spray  56  colliding with the spray receiving section  36  to be made to fall downwards in a substantially more reliable manner using the spray returning section  37 . It is therefore possible to more reliably prevent the spray  56  from splashing at the side of the deck  19 . 
   As a result, it is possible to utilize an existing hull sponson and the deck sponson as a spray guard  61  simply by making the extent of projection L and height H of the member  38  on the side of the front section  11   a  of the boat body  11  of the existing hull sponson and deck sponson large. 
   In the second embodiment, an example is shown of the spray guard  61  where the extent of projection L of the member  38  on the side of the front section  11   a  of the boat  11  is formed so as to be larger than the other member  39 . Further, the height H of the member  38  on the side of the front section  11   a  of the boat  11  is formed to be larger than the other member  39 . However, the same results can also be obtained by forming the extent of projection L along the whole of the spray guard fixed at L 2  (refer to  FIG. 2 ), and forming only the height H of the member  38  on the side of the front section  11   a  of the boat body  11  larger than the other member  39 . It is also possible for this form of spray guard to reliably prevent spray  56  from splashing to the side of the deck  19  similarly to the second embodiment. 
   Further, in this embodiment, a description is given of an example where splashing of spray  56  to the side of the deck  19  is prevented by making the extent of projection L and height H of the member  38  on the side of the front section  11   a  of the boat  11  of an existing hull sponson and deck sponson large but in addition to this embodiment, it is also possible to provide a plate for preventing splashing of spray to the side of the deck at the outer periphery of the front section  11   a  of the boat body  11 . 
   The present invention is appropriate for application in a small boat provided with a sponson section at the outer periphery of the hull, and a sponson section at the outer periphery of the deck, with the respective sponson sections bonded together to form a boat body. 
   The invention being thus described, it will be obvious that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be obvious to one skilled in the art are intended to be included within the scope of the following claims.