Patent Abstract:
An outboard engine with a cover for allowing for an improved outward appearance is disclosed. The engine includes a leg case that houses a drive shaft for transmitting the output from the engine to a propeller. The cover covers the leg case. The cover is formed integrally, and a front part is designed to be opened. The front part is opened and is made to encase and cover a periphery of the leg case.

Full Description:
FIELD OF THE INVENTION  
       [0001]     The present invention relates to an outboard engine that is steerably attached to the hull of a boat.  
       BACKGROUND OF THE INVENTION  
       [0002]     Japanese Patent Laid-Open Publication No. 7-149289 (JP-A-7-149289) discloses an outboard engine wherein the outer surface of a drive shaft housing (extension case) in the vertical middle of the outboard engine is covered by a cover.  
         [0003]     In this outboard engine, the outer surface of the drive shaft housing is covered with a cover made of a synthetic resin to reduce the finishing costs needed to improve the outward appearance of the drive shaft housing, and also to simplify the design of the drive shaft housing.  
         [0004]     The cover that covers the outer surface of the drive shaft housing is configured from a two-piece dividable cover having a port cover and a starboard cover.  
         [0005]     Thus, in this outboard engine, covering the outer surface of the drive shaft housing with a cover made of a synthetic resin makes it possible to improve the outward appearance of the drive shaft housing and to simplify the external structure of the housing, and also allows for a greater degree of freedom in the design.  
         [0006]     However, since this cover is configured from two members, which are the port cover and the starboard cover, a large number of attachment bosses is needed to attach and support these two members on the outer surface of the drive shaft housing, the attachment structure of the cover and the drive shaft housing is complicated, and the number of steps for attachment is increased. Particularly, since the cover is configured from two members, pressure must be applied to both the left and right components when the left and right components are assembled, making operability inferior.  
         [0007]     In view of this, the outward appearance of the cover must be simplified, as must the structure for attaching the cover to the drive shaft housing.  
       SUMMARY OF THE INVENTION  
       [0008]     According to the present invention, there is provided an outboard engine designed to be steerably attached to a hull of a boat by an attachment device, which outboard engine comprises an engine part, a propeller driven by the engine part, a transmission device that includes a longitudinal shaft and a propeller shaft for transmitting an output of the engine part, and a main body for housing at least the engine part and the transmission device, wherein the main body is composed of a leg case that extends in a longitudinal direction and that houses at least part of the longitudinal shaft of the transmission device, and a cover that covers an outer side of the leg case; and the cover is formed integrally by forming a starboard outer surface and a port outer surface continuously in a rear portion of the outboard engine, and is provided with an anti-splash plate formed integrally on a front surface.  
         [0009]     Thus, in the outboard engine, since the cover is formed integrally by forming a starboard outer surface and a port outer surface continuously at the rear of the outboard engine, there are no dividing lines or joining lines in the rear surface of the cover of the outboard engine, for which a favorable outward appearance is vital, and the outward appearance is significantly improved in the outboard engine in which the outer surface of the leg case is covered with a cover.  
         [0010]     Furthermore, since the cover is configured from a single member, the number of components is reduced, and there are fewer attachment portions on the cover, and fewer attachment parts on the leg case. Furthermore, since a single member is set on the side of the leg case, there is no need for multiple setting devices or positioning means, which are needed to set a cover composed of two members, and the operation of the attachment can be simplified.  
         [0011]     Furthermore, the number of components can be reduced since the starboard outer surface and the port outer surface constituting the cover are formed integrally and the anti-splash plate is provided integrally to the front surface.  
         [0012]     It is preferable that the cover have a frontally disposed interlocking part that interlocks with the leg case. Therefore, positioning alignment is simplified during assembly with the leg case side of the outboard engine.  
         [0013]     It is preferable that the cover have fastening parts, and that the fastening parts be provided so as to be in contact with the anti-splash plate and the cover. Therefore, providing the fastening parts that span both the anti-splash plate and the cover is effective for reinforcing the periphery of the fastening parts, and makes it possible to ensure sufficient rigidity when the anti-splash plate is subjected to external forces.  
         [0014]     It is preferable that the cover be provided separately from the attachment device. The anti-splash plate is not limited to the height of the attachment device, and the height of the anti-splash plate can be designed at an arbitrary position. Furthermore, the height of the anti-splash plate is close to the water surface as long as the height is set lower than the height of the attachment device, and the required width of the anti-splash plate can therefore be prevented from being needlessly increased. 
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0015]     A preferred embodiment of the present invention will be described in detail below, by way of example only, with reference to the accompanying drawings, in which:  
         [0016]      FIG. 1  is a side view of the outboard engine of the present invention on which a leg cover is mounted;  
         [0017]      FIG. 2  is a perspective view of the leg cover shown in  FIG. 1  as viewed from above on the starboard side;  
         [0018]      FIG. 3  is a perspective view of the leg cover shown in  FIG. 1  as viewed from above on the port side;  
         [0019]      FIG. 4  is a front view of the leg cover shown in  FIG. 2 ;  
         [0020]      FIG. 5  is a rear view of the leg cover shown in  FIG. 2 ;  
         [0021]      FIG. 6  is a plan view of the leg cover shown in  FIG. 2 ;  
         [0022]      FIG. 7  is a longitudinal cross-sectional view of the leg cover shown in  FIG. 2 ; and  
         [0023]      FIG. 8  is an exploded perspective view of the leg cover being assembled on the leg case. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0024]     Referring to  FIG. 1 , an outboard engine  1  comprises an engine cover  2  that houses an engine part  5 ; an undercover  3  that is positioned below the engine cover  2 ; a leg cover  50  that is positioned below the undercover  3  and that covers a leg case (extension case)  8 , which is a drive shaft housing; and a gear case  4  at the lowest position.  
         [0025]     The engine part  5  is composed of a multi-cylinder four-stroke engine having a longitudinally oriented crankshaft  5   a , a transversely oriented cylinder block  5   b , a cylinder head  5   c , a cylinder head cover  5   d , a crankcase  5   e , and a camshaft (not shown).  
         [0026]     The engine cover  2  covers the top half of the engine part  5 , and the top of the undercover  3  covers the bottom of the engine part  5 . The bottom end of the engine part  5  is supported by a mounting case  6 . An oil case  7  is disposed below the mounting case  6 . The oil case  7  and the gear case  4  are connected by the leg case  8 .  
         [0027]     A drive shaft  9  is connected to the crankshaft  5   a , and passes vertically through the mounting case  6 , the oil case  7 , and the leg case  8  and extends into the gear case  4 . The drive shaft  9  transmits the drive force outputted from the engine part  5  to a propeller shaft  11   a  via a gear mechanism  10  installed in the gear case  4 , thereby driving a propeller  11 . The drive shaft  9  and the propeller  11  constitute a transmission device.  
         [0028]     An anti-cavitation plate  12  is provided on the gear case  4  at a position above the propeller  11 . An anti-splash plate  13  is provided on the gear case  4  at a position above the anti-cavitation plate  12 .  
         [0029]     A concavity  14  in which a stern bracket  15  and a swivel case  16  are installed is formed in the front of the undercover  3  and the leg cover  50 . The outboard engine  1  is attached to the stern S 1  of a hull S by means of the stern bracket  15 . This stern bracket  15  is an attachment device for attaching the outboard engine  1  to the stern S 1 . The outboard engine  1  swings vertically about a tilt shaft  15   a  provided to the stern bracket  15 , and also swings horizontally about a swivel shaft  17  inside the swivel case  16 . The swivel shaft  17  enables the outboard engine  1  to be steered.  
         [0030]     The outboard engine main body is configured from the engine part, the mounting case, the oil case, the leg case, and the engine cover and undercover that house these components.  
         [0031]     Next, the configuration of the leg cover  50  will be described with reference to  FIGS. 2 through 7 .  
         [0032]     Compared to the portion of the leg cover  50  that extends from a top part  50   a  to a middle part  50   b , a bottom half  50   c  is longer in the longitudinal direction of the outboard engine  1 , i.e., is formed to protrude farther forward. Thus, the leg cover  50  is in the shape of a long boot and comprises a port side wall  51 , a starboard side wall  52 , and a rear side wall  53  in which the rear ends of the port side wall  51  and the starboard side wall  52  are formed integrally.  
         [0033]     The front ends of the port side wall (port outer surface)  51  and the starboard side wall (starboard outer surface)  52  that extend from the top parts to the middle parts have left and right front side walls  55 ,  56  that are bent inward so as to face each other. The left and right front side walls  55 ,  56  are connected in a joining part  54 , and protrude so as to form a V shape in plan view. Left and right protruding parts  51   a ,  52   a  that protrude outward are formed in portions that extend from the bottoms of the left and right front side walls  55 ,  56  to the front halves of the port and starboard side walls  51 ,  52 .  
         [0034]     A protruding frame  58  that protrudes farther forward than the left and right front side walls  55 ,  56  is formed on the protruding parts  51   a ,  52   a . The protruding frame  58  is composed of left and right portions  58   a ,  58   b  that are both in the shape of a U when viewed from the front, wherein a window  57  having a horizontal rectangular shape is formed in the front surface. The left and right portions  58   a ,  58   b  face each other. The top surface  58   c  of the protruding frame  58  forms a shelf and protrudes laterally forward.  
         [0035]     The port and starboard side walls  51 ,  52  have extending parts  51   b ,  52   b  that extend forward in the bottom. The extending parts  51   b ,  52   b  have roof parts  51   c ,  52   c  in the top surfaces.  
         [0036]     A gap  59  is formed between the end edges  51   d ,  52   d  of the portions that protrude from the left and right extending parts  51   b ,  52   b , as shown in  FIG. 4 . Anti-splash plate halves  60   a ,  60   a  that form a substantial half circle when joined together are formed integrally in the tops of the left and right extending parts  51   b ,  52   b . The anti-splash plate halves  60   a ,  60   a  extend forward from the left and right extending parts  51   b ,  52   b , and the distal ends thereof have arcuate shapes. An anti-splash plate  60  is configured form the anti-splash plate halves  60   a ,  60   a.    
         [0037]     Notches  61 ,  61  are formed in the front ends of the anti-splash plate  60 . A narrow gap  62  that extends in the longitudinal direction is formed behind these notches  61 ,  61 . A space is formed in the area behind the gap  62 . A roof piece  63  that protrudes from the front ends of the left and right roof parts  51   c ,  52   c  is formed at a position above this space. An interlocking part  64  is formed by the roof piece  63  and the gap  62 .  
         [0038]     The leg cover  50  has an attachment piece  65  provided in the top edge at the rear so as to protrude upward, and multiple interlocking pieces  66  provided in the top edge at the front so as to protrude upward. Fastening holes  67 ,  67  are formed in the bottom rear parts of the port and starboard side walls  51 ,  52 . Fastening holes  68 ,  68  are also formed in the front side walls  55 ,  56 . The reference number  69  in  FIG. 2  denotes a drain hole.  
         [0039]     A gap  62  is formed between the left and right portions  60   a ,  60   a  of the anti-splash plate  60 , as shown in  FIG. 4 . Reinforcing ribs  70 ,  70  are provided at the top halves of the opposing end edges  51   d ,  52   d  of the port and starboard side walls  51 ,  52 . These reinforcing ribs  70  are connected to the extending parts  51   b ,  52   b  and to the anti-splash plate  60 , and constitute a fastening unit for fastening the port and starboard side walls  51 ,  52 . The reinforcing ribs  70  fasten the port and starboard side walls  51 ,  52  together when a bolt is inserted through fastening holes  71 , as shown in  FIG. 7 .  
         [0040]     The leg cover  50  is integrally molded from a synthetic resin.  
         [0041]     The leg case  8  has at the top end a flange  8   a  that bonds with a bottom end flange  7   a  of the oil case  7 , as shown in  FIG. 8 . A protrusion  8   b  that protrudes forward is formed in the bottom front surface of the leg case  8 . Both sides of the protrusion  8   b  are provided with mounting housings  8 ,  18  that buffer and support a center housing  17   a  provided at the bottom end of the swivel shaft  17 .  
         [0042]     Next, the procedure of assembling the leg cover  50  on the leg case  8  will be described with reference to  FIGS. 2 and 8 .  
         [0043]     First, the port and starboard side walls  51 ,  52  of the leg cover  50  are separated to the left and right as shown by the arrows a and b, and a space is opened between the left and right front side walls  55 ,  56  that are opened to the left and right. In this state, the leg cover  50  is oriented forward and is fitted over the rear of the leg case  8  of the outboard engine  1 , as shown by the arrow c.  
         [0044]     At this time, the bottom end of the leg cover  50  is moved along the top surface of the anti-splash plate  13  provided at the bottom of the outboard engine  1  to move the leg cover  50  forward and to encase the leg case  8  from the sides. The leg cover  50  is made of a flexible synthetic resin, and the rear side wall  53  of the port and starboard side walls  51 ,  52  easily bends and expands.  
         [0045]     When the leg cover  50  is moved forward in the direction of the arrow c, the left and right protruding parts  51   a ,  52   a  enclose the mounting housings  18 ,  18  from the sides, thereby hiding the mounting housings  18 ,  18 . The protrusion  8   b  is encircled by the protruding frame  58 , and the front end surface of the protrusion  8   b  faces the window  57 .  
         [0046]     A tongue-like interlocking piece  81  shown in  FIGS. 1, 4 , and  6  is provided at the bottom front end of the leg case  8 . The interlocking piece  81  protrudes forward from the interlocking part  64  between the roof piece  63  and the front top surface of the anti-splash plate  60  shown in  FIG. 2 , and allows the leg case  8  and the leg cover  50  to be easily positioned during assembly.  
         [0047]     The attachment piece  65  at the rear of the leg cover  50  is screwed onto the undercover  3 , and the interlocking pieces  66  at the front are interlocked with the undercover  3 . The leg cover  50  is bolted onto the leg case  8  by using the fastening holes (fastening parts)  67 ,  67  shown in  FIG. 2 . The left and right front side walls  55 ,  56  of the leg cover  50  are connected using bolts via the fastening holes (fastening parts)  68 ,  68 . The anti-splash plate  60  is fastened by inserting a bolt through the fastening holes  71 ,  71  in the reinforcing ribs (fastening parts)  70 ,  70 . Thus, the leg cover  50  is attached so as to cover the outer surface of the leg case  8 .  
         [0048]     The leg cover  50 , rather than being a two-piece dividable member, is formed from a single integrated plate member, wherein the front portion is opened to encase and cover the leg case  8  of the outboard engine  1 , and then the cover is easily attached to the leg case  8  by being fastened using bolts.  
         [0049]     Obviously, various minor changes and modifications of the present invention are possible in light of the above teaching. It is therefore to be understood that within the scope of the appended claims the invention may be practiced otherwise than as specifically described.

Technology Classification (CPC): 1