Abstract:
A splash guard mechanism for preventing the entry of grass, in addition to mud and gravel, in a vehicle such as a an ATV (All Terrain Vehicle). A disc-shaped splash guard mechanism covers a brake disc stored in a concave portion of a wheel to thereby prevent the entry of dirt such as mud, gravel, and grass into the brake disc. If the dirt enters the brake disc, the dirt is ejected from a first cutout portion provided on a lower portion of the splash guard mechanism. Additionally, a grass removal portion substantially triangle-shaped in plan view is provided on a lower portion of the splash guard mechanism. The grass removal portion protrudes toward a vehicle center to push grass on the ground outward and away from the first cutout portion. Since the grass is only pushed out, the grass is prevented from being cut and entering the brake disk.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority under 35 USC 119 to Japanese Patent Application No. 2009-015385 filed on Jan. 27, 2009 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 splash guard mechanism suitable for a brake system for a vehicle, in particular, for an ATV (All Terrain Vehicle). 
     2. Description of Background Art 
     Vehicle are equipped with a brake system. In an ATV capable of traveling on an unpaved ground such as dirt or moor, it is necessary to strengthen measures against, particularly, the entry of mud into a brake system. Such measures have been proposed for example, in JP-A No. 2008-57707, see FIG. 11. 
     A related art will be described with reference to FIG. 11 of JP-A No. 2008-57707. Referring to FIG. 11, dirt (72) such as mud and gravel is deposited on a smallest-diameter portion (32 a ) of a rim, as shown in FIG. A1 (the bracketed reference signs are those transferred from JP-A No. 2008-57707, hereinafter described in the same manner). The smallest-diameter portion (32 a ) of the rim is a rotating body, and a brake disc guard (33) is a nonrotating body. A flange (38) extends from the brake disc guard (33) to the near side of the drawing. 
     When the smallest-diameter portion (32 a ) of the rim rotates in the direction shown by arrow F, a part of the dirt (72) falls down. The rest of the dirt (72) reaches an upper portion as shown in FIG. B1, and then is scraped off by a scraper (36) in FIG. C1. 
     The brake disc guard (33) includes a lower portion (41) that is widely cutout. The dirt (72) having fallen down in FIG. 11 sub-FIGS. A1, B1, and C1, is ejected to the far side of the drawing through the large opening of the lower portion (41). 
     That is to say, JP-A No. 2008-57707 discloses a splash guard mechanism for a vehicle in which the brake disc guard (33) is provided so as to prevent the entry of mud and gravel into a brake disc (30) provided in a wheel, and the lower portion (41) is provided with a cutout so as to easily eject therethrough mud and gravel having entered the brake disc (30). 
     However, a vehicle such as an ATV may travel on grass. Although grass having entered the brake disc (30) is also ejected through the cutout of the lower portion (41), grass is likely to become tangled therein as compared with mud and gravel. Therefore, the ejection of the grass becomes more difficult. For this reason, the entry of grass into the brake disc (30) is preferably suppressed as much as possible. 
     SUMMARY AND OBJECTS OF THE INVENTION 
     Accordingly, an object of an embodiment of the present invention is to provide a splash guard mechanism capable of preventing the entry of grass in addition to mud and gravel in a vehicle such as a an ATV (All Terrain Vehicle). 
     According to an embodiment of the present invention, a splash guard mechanism for a vehicle, mounted on a brake system stored in a concave portion is provided on each wheel for the wheels to prevent entry of mud from the outside into the brake system. A substantially disc-shaped plate portion covers the brake system to close the concave portion. A first cutout portion is formed by cutting out a lower portion of the plate portion. A grass removal portion extends from the plate portion toward a vehicle center, with at least a portion thereof overlapping with a vehicle front portion of the first cutout portion. 
     According to an embodiment of the present invention, the grass removal portion is formed in a substantially triangular shape with an apex protruding toward the vehicle center in a plan view. A steep oblique portion having a sharp inclination is provided in the vicinity of the apex on a front oblique side of the substantially triangular shape, and an edge of the front oblique side is bent downward. 
     According to an embodiment of the present invention, a knuckle is connected to the wheel through a wheel hub. When arm connectors of a suspension are provided on the knuckle, the apex is disposed on a vehicle front side of the arm connectors. 
     According to an embodiment of the present invention, the substantially disc-shaped plate portion includes a guide portion extending outwardly of the vehicle from the plate portion to guide mud deposited on a rim, and is formed in a C-shape with a portion thereof cutout. The second cutout portion is disposed so as to face the vehicle front side and contains a brake caliper. A front end of the guide portion is disposed above the second cutout portion with the grass removal portion being disposed below the second cutout portion. 
     According to an embodiment of the present invention, a bent portion, formed by bending downward the edge of the front oblique side, extends to the vicinity of the rim, and a lower edge surface of the bent portion is formed along a bottom surface of the rim. 
     According to an embodiment of the present invention, the plate portion is provided with the grass removal portion extending toward the vehicle center. Therefore, grass growing on the ground or in water, or the like, can be pushed out toward the vehicle center by the grass removal portion. By the pushing operation, the grass is separated from the first cutout portion of the plate portion. In other words, according to the present invention, it is possible to provide a splash guard mechanism capable of preventing the entry of grass, in addition to mud and gravel, in a vehicle such as an ATV (All Terrain Vehicle). 
     According to an embodiment of the present invention, while the vehicle travels forward, grass is received by the front oblique side. The grass is pushed toward the vehicle center along the oblique side to be flicked away toward the vehicle center by the steep oblique portion provided in the vicinity of the apex and having a sharp inclination. As a result, the grass is largely away from the first cutout portion. However, some of the grass can immediately return by an elastic action. The returned grass abuts on the rear oblique side to move slowly to the plate portion along the rear oblique side. 
     In addition, an edge of the front oblique side is bent downward. The bent portion allows an increase in rigidity of the grass removal portion. Further, since the bent portion is provided substantially vertically with respect to the ground, the grass can be readily pushed out. 
     According to an embodiment of the present invention, the apex of the grass removal portion is disposed on the vehicle front side of the arm connectors of the arms of the suspension. That is to say, the grass removal portion is provided at such a position to avoid interference with the arms of the suspension, thereby allowing enlargement of the grass removal portion and increasing flexibility in shape design. 
     According to an embodiment of the present invention, the substantially disc-shaped plate portion is formed in a C-shape with a portion thereof cutout, and the second cutout portion is disposed so as to face the vehicle front side and can contain a brake caliper. Also, a front end of the guide portion is disposed above the second cutout portion, and the grass removal portion is disposed below the second cutout portion. Commonly, a rear upper portion of a tire is covered with a fender or the like, and a front portion thereof is open to thereby facilitate access from the outside. Since the brake caliper, the front end of the guide portion, and the grass removal portion are disposed in front of the tire constructed in this manner, the removal of mud and gravel remaining therein without being ejected can be further facilitated. 
     According to an embodiment of the present invention, a bent portion, formed by bending downward the edge of the front oblique side, extends to the vicinity of the rim, and a lower edge surface of the bent portion is formed along a bottom surface of the rim. With this structure, it is possible to reduce the spacing between the lower edge surface of the bent portion and the rim, and prevent the entry of mud, gravel, and grass into the concave portion of the wheel through the spacing. 
     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 left side view of a vehicle with a splash guard mechanism of the present invention; 
         FIG. 2  is a view illustrating the structure of a front wheel and a suspension; 
         FIG. 3  is a perspective view of a wheel seen from the vehicle center; 
         FIG. 4  is a front view of the splash guard mechanism according to the present invention; 
         FIG. 5  is a view taken in the direction of arrow  5 - 5  of  FIG. 4 ; 
         FIG. 6  is a sectional view taken along the line  6 - 6  of  FIG. 4 ; 
         FIG. 7  is a perspective view of the splash guard mechanism according to the present invention; 
         FIG. 8  is a view illustrating the operation of a grass removal portion of the present invention; 
         FIG. 9  is a sectional view taken along the line  9 - 9  of  FIG. 8 ; 
         FIG. 10  is a rear view of the splash guard mechanism according to the present invention; 
         FIG. 11  is a perspective view with the splash guard mechanism mounted; 
         FIG. 12  is a sectional view taken along the line  12 - 12  of  FIG. 11 ; 
         FIG. 13  is a sectional view taken along the line  13 - 13  of  FIG. 11 ; 
         FIG. 14  is a sectional view taken along the line  14 - 14  of  FIG. 11 ; 
         FIG. 15  is a sectional view taken along the line  15 - 15  of  FIG. 11 ; and 
         FIG. 16  is a sectional view taken along the line  16 - 16  of  FIG. 11 . 
     
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
     An embodiment of the present invention will hereinafter be described with reference to the accompanying drawings. In the following description, it is to be noted that “front,” “rear,” “left,” and “right” denote directions viewed from the occupant&#39;s position, and the drawings should be seen according to the direction of reference signs. 
       FIG. 1  is a left side view of a vehicle with a splash guard mechanism of the present invention. In this embodiment, an ATV (All Terrain Vehicle) is used as an example of a vehicle  10 . The vehicle  10  is a four-wheeled vehicle including an engine  12  and a transmission  13  in the center of a body frame  11 , driving front wheels  16  through a front gearbox  15  by a front drive shaft  14  extending forward from the transmission  13 , and driving rear wheels  19  through a rear gearbox  18  by a rear drive shaft  17  extending rearward from the transmission  13 . Also, the vehicle  10  is a saddle-ride type vehicle in which an occupant sits astride a seat  21  disposed on an upper central portion of the body frame  11  to operate a steering wheel  22 . 
     On the body frame  11 , a fuel tank  23  is disposed between the seat  21  and the steering wheel  22 . Also, a radiator  24  is disposed above the front wheels  16 . Each of the front wheels  16  is supported in a vertically movable manner by a suspension including an upper arm  25  and a lower arm  26 . A support structure of the front wheels  16  will be described in detail in the next drawing. 
       FIG. 2  is a view illustrating the structure of the front wheel and the suspension. The upper arm  25  and the lower arm  26  extend outwardly of the vehicle from cross members  27  and  28  serving as one element of the body frame (body frame  11  in  FIG. 1 ) to be connected to a knuckle  32  through ball joints  29  and  31 , respectively. The connecting portion of the ball joint  31  to the knuckle  32  is referred to as an arm connector  33 . 
     A front wheel axle  36  is attached to the knuckle  32  through a bearing  34  and a rotating cylinder  35 . Further, the front wheel  16  is attached to a flange  37  extending from a vehicle-exterior side edge of the rotating cylinder  35  by a bolt. 
     The front wheel  16  is composed of a tire  38  and a wheel  39  for supporting the tire  38 . The wheel  39  is composed of a disc  42  having a bolt hole  41 , and a rim  43  joined to the outer periphery of the disc  42 . The tire  38  is fitted to the rim  43 . As is clear from the drawing, the disc  42  is connected to the rim  43  at a position deviating to the vehicle outer side from the center in the vehicle width direction of the rim  43 . Therefore, a large concave portion  44  is provided toward the vehicle center from the disc  42 . 
     In the large concave portion  44 , a brake system  48  composed of a brake disc  46 , a brake caliper (reference sign  47  in  FIG. 3 ) and the like is stored, and a splash guard mechanism  50  covering the brake disc  46  to close the concave portion  44  is disposed. Although the detailed structure of the splash guard mechanism  50  will be described later, the splash guard mechanism  50  is connected to the knuckle  32 , and thus, non-rotatable. On the other hand, the brake disc  46  is connected to the flange  37 , and therefore rotated along with the front wheel  16  through a constant-velocity joint  49  extending from the front gearbox  15 . 
       FIG. 3  is a perspective view of a wheel seen from the vehicle center. The splash guard mechanism  50 , the brake caliper  47 , and the brake disc  46  are stored in the concave portion  44  of the wheel  39 . A splash guard holder  51  is formed integrally with the knuckle  32 , and the splash guard mechanism  50  is held by the splash guard holder  51 . Here, a plurality of splash guard holder  51  are formed, however, the other splash guard holder  51  is located behind the knuckle  32  and cannot be seen in the drawing. Also, brackets  52  and  52  extend from the knuckle  32 , and the brake caliper  47  is supported by the brackets  52  and  52 . The brake caliper  47  is disposed in a second cutout portion  53  provided on the splash guard mechanism  50   
     Next, the structure of the splash guard mechanism  50  will be described in detail.  FIG. 4  is a front view of the splash guard mechanism according to the present invention. When viewed from the vehicle center, the splash guard mechanism  50  is composed of a substantially disc-shaped plate portion  55  including the second cutout portion  53  to be formed in a C-shape. A guide portion  56  extends from the plate portion  55  to the far side of the drawing, that is, outwardly of the vehicle. A first cutout portion  57  is formed by cutting out a lower portion thereof. A grass removal portion  60  extends from the plate portion  55  to the near side of the drawing, that is, toward the vehicle center, with at least a portion thereof overlapping with a vehicle front portion  58  of the first cutout portion  57 . The splash guard mechanism  50  constructed in such a manner, is connected to the splash guard holders (splash guard holder  51  in  FIG. 3 ) provided on the knuckle  32  using a plurality of bolt holes  59  (three in this embodiment) arranged so as to surround the large second cutout portion  53 . 
       FIG. 5  is a view taken in the direction of arrow  5 - 5  of  FIG. 4 . The grass removal portion  60  is formed in a substantially triangular shape with an apex  61  protruding downwardly in the drawing, that is, toward the vehicle center, in plan view at the forward most part of the first cutout portion. The substantially triangular-shaped grass removal portion  60  has a surface  60   s  that extends in a direction that is substantially perpendicular to the plate portion  55 , and the surface  60   s  is bounded by a first side  60   a  extending along a lower edge of the plate portion  55 , a rear oblique side  67  extending obliquely rearwardly from the apex  61  to a rear end of the first side  60   a  and overlapping with a vehicle front portion  58  of the first cutout portion  57 , and a front oblique side  62  extending obliquely forward from the apex  61  to a front end of the first side  60 . The front oblique side  62  of the substantially triangular shape is provided with a steep oblique portion  63  having a sharp inclination, in the vicinity of the apex  61 . A leading edge of the front oblique side  62  is bent to the far side of the drawing, as shown by the dashed line. 
       FIG. 6  is a sectional view taken along the line  6 - 6  of  FIG. 4 . The guide portion  56  extends from the plate portion  55  to the right of the drawing, that is, outwardly of the vehicle. Also, the grass removal portion  60  extends from a lower portion of the plate portion  55  to the left of the drawing, that is, toward the vehicle center. A bent portion  64  is bent from the front oblique side  62  of the grass removal portion  60  thereby to be formed. 
       FIG. 7  is a perspective view of the splash guard mechanism according to the present invention. A rear oblique side  67  of the grass removal portion  60  overlaps with the vehicle front portion  58  of the first cutout portion  57 . The grass removal portion  60  constructed in this manner, includes the bent portion  64  formed by bending downward an edge of the front oblique side  62 . 
       FIG. 8  is a view illustrating the operation of the grass removal portion of the present invention. Along with the forward movement of the vehicle, the grass removal portion  60  substantially triangle-shaped in plan view moves in the direction shown by arrow ( 1 ). Grass  66  growing on the ground or in water, moves relatively in the direction shown by arrow ( 2 ) along the front oblique side  62  to be pushed out in the direction shown by arrow ( 3 ), by the steep oblique portion  63 . When the grass  66  is not springy, the grass  66  returns slowly in the direction shown by arrow ( 4 ). Ideally, the grass  66  outreaches the first cutout portion  57 . 
     When the grass  66  is springy, the grass  66  is immediately returned in the direction shown by arrow ( 5 ). Thereafter, the grass  66  moves slowly in the direction shown by arrow ( 6 ) along the rear oblique side  67  formed to be gently-inclined. Therefore, the grass  66  becomes less likely to enter the first cutout portion  57 . 
       FIG. 9  is a sectional view taken along the line  9 - 9  of  FIG. 8 . The grass  66  is pushed by the bent portion  64 , thereby avoiding injury to the grass  66 . Also, a lower edge surface  65  of the bent portion  64  is kept horizontal. Since the grass  66  stands substantially erect on the ground, the horizontally provided lower edge surface  65  allows the grass  66  to be prevented from being cut. 
       FIG. 10  is a rear view of the splash guard mechanism according to the present invention. When viewed from the vehicle-exterior side, the guide portion  56  extends about 180 degrees in the counterclockwise direction along the rim  43  from the vicinity of an edge, on the right of the drawing, of the first cutout portion  57 . At an upper position on the guide portion  56 , a triangular baffle plate  68  (baffle plate  68  shown by the imaginary line in  FIG. 6 ) is provided between the guide portion  56  and the plate portion  55 . Also, the front end of the guide portion  56  is a scraper  69 , and the spacing between the rim  43  and the guide portion  56  becomes smaller by the scraper  69 . 
     The rim  43  on which mud  70  is deposited, rotates in the counterclockwise direction along with the forward movement of the vehicle. On the other hand, the splash guard mechanism  50  does not rotate. The mud  70  is scraped off by the baffle plate  68  to fall down, and then is ejected from the first cutout portion  57  to the far side of the drawing. Remaining mud  71  passing over the baffle plate  68  is scraped off by the scraper  69  to fall down, and then is ejected from the first cutout portion  57  to the far side of the drawing. 
     Referring back to  FIG. 3 , the right side of the drawing is the vehicle front side, and the brake caliper  47  is disposed at the vehicle front side of the center (the same as the center of the axle) of the wheel  39 . It is common that a rear upper portion of a tire is covered with a fender or the like, and a front portion thereof is open to thereby facilitate access from the outside. Since the brake caliper  47  is disposed at a front portion of the tire constructed in this manner, the removal of mud and gravel jammed in the brake caliper  47  can be further facilitated. 
     Also, the front end (the scraper  69  in  FIG. 10 ) of the guide portion  56  is disposed above the second cutout portion  53 , and the grass removal portion  60  is disposed below the second cutout portion  53 . Since the front end of the guide portion  56  and the grass removal portion  60  are disposed in front of the tire, the removal of mud and gravel remaining therein without being ejected can be further facilitated. 
     Furthermore, the apex  61  of the grass removal portion  60  is disposed on the vehicle front side of the arm connectors  33  of the arms of the suspension. That is to say, the grass removal portion  60  is provided at such a position to avoid interference with the arms (upper arm  25  and lower arm  26  in  FIG. 2 ) of the suspension, thereby allowing enlargement of the grass removal portion  60  and increasing flexibility in the shape design. 
     Also, in  FIG. 2 , the rim  43  is formed in a cone shape gently broadened toward the vehicle center. As compared with a cylindrically-shaped one, the cone-shaped rim  43  further facilitates the ejection of dirt (such as mud, gravel, and grass) having entered the concave portion  44  because the dirt spirals into a conic surface thereof when the rim  43  rotates. This ejection is performed by the first cutout portion (first cutout portion  57  in  FIG. 3 ) provided on the far side in the drawing of the bent portion  64 . Therefore, the bent portion  64  does not interfere with such ejection. 
     Meanwhile, since the bent portion  64  can be provided sufficiently close to the rim  43 , the entry of mud and the like can be prevented. In addition, by providing the bent portion  64 , the rigidity of the grass removal portion (grass removal portion  60  in  FIG. 3 ) can be increased. 
     Next, a relative position between the rim  43  and the grass removal portion  60  will be further described in detail. As shown in  FIG. 11 , a lower edge  73  (particularly, the lower edge surface  65 ) of the grass removal portion  60  is formed along a bottom surface  45  of the rim  43 , and its detailed description will be given with reference to  FIGS. 12 to 16  showing sectional views of  FIG. 11 . 
     As shown in  FIG. 12 , a spacing C 1  between the lower edge  73  of the grass removal portion  60  and the bottom surface  45  of the rim  43  is sufficiently small. As shown in  FIGS. 13 and 14 , spacings C 2  and C 3  between the lower edge surface  65  of the bent portion  64  and the bottom surface  45  of the rim  43  are sufficiently small. Since the spacings C 1  to C 3  are small, the entry of grass and gravel can be suppressed. 
     On the other hand, in  FIG. 15  in which no bent portion  64  is provided, a spacing C 4  between the rear oblique side  67  and the bottom surface  45  of the rim  43  is large. In the same manner, in  FIG. 16  in which no bent portion  64  is provided, a spacing C 5  between the first cutout portion  57  and the bottom surface  45  of the rim  43  is sufficiently large. Since the spacing C 4  and C 5  are large, the ejection of the entered grass, mud, and gravel can be effectively performed. 
     The splash guard mechanism according to the present invention is suitable for ATVs, however, may be used in normal vehicles. 
     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.