Patent ID: 12258088

DESCRIPTION OF EMBODIMENTS

A straddle-type vehicle according to an embodiment of the present invention includes a head pipe, a steering stem rotatably supported in the head pipe, a front fork, an upper bracket connecting an upper end portion of the front fork to the steering stem, a lower bracket located below the upper bracket and connecting an upper portion of the front fork to the steering stem, a front wheel supported by a lower end portion of the front fork, and a front fender covering the front wheel from above. Further, the straddle-type vehicle according to the embodiment of the present invention includes a front cowl covering an upper front portion of the straddle-type vehicle, a shroud located above the front fender and covering a lower portion of the front cowl, and a lower bracket cover located above the front fender and covering the lower bracket from below. The shroud has an opening through which the front fork passes, and the lower bracket cover is provided below the opening.

In the straddle-type vehicle according to the present embodiment, the lower bracket cover covering the lower bracket from below is provided below the opening through which the front fork passes in the shroud. Therefore, the opening of the shroud can be covered with the lower bracket cover from below. Accordingly, it is possible to suppress traveling wind passing between the shroud and the front fender during traveling of the straddle-type vehicle from entering an inside of the front cowl through the opening of the shroud. Therefore, it is possible to suppress an increase in air resistance or generation of a front lift caused by the traveling wind entering the inside of the front cowl through the opening, and thus it is possible to improve an aerodynamic performance of the straddle-type vehicle. Further, it is possible to increase an amount of the traveling wind blowing against a radiator or the like, and it is possible to improve a cooling effect for the radiator or the like.

In the straddle-type vehicle according to the present embodiment, since the lower bracket cover is provided below the opening of the shroud, even when a distance between the lower bracket and the shroud in an upper-lower direction is increased due to design of the straddle-type vehicle or the like, the lower bracket cover can be provided below the opening of the shroud in a state where the lower bracket cover is brought close to the shroud, and the opening can be reliably covered by the lower bracket cover. Therefore, an effect of the lower bracket cover of suppressing the traveling wind from entering the inside of the front cowl through the opening can be suppressed from being lowered due to an increase in the distance between the lower bracket and the shroud in the upper-lower direction due to the design of the straddle-type vehicle or the like. Since the lower bracket cover is provided below the opening of the shroud, even when the distance between the lower bracket and the shroud in the upper-lower direction is extremely small due to the design of the straddle-type vehicle or the like, the lower bracket cover can be provided below the opening of the shroud, and the opening can be covered by the lower bracket cover.

Embodiment

The embodiment of the straddle-type vehicle according to the present invention will be described with reference toFIGS.1to8B. In the embodiment, directions of the front (Fd), the rear (Bd), the upper (Ud), the lower (Dd), the left (Ld), and the right (Rd) are described according to arrows drawn at the lower right of the drawings.

(Straddle-Type Vehicle)

FIG.1shows a state where a front portion of a straddle-type vehicle1according to the embodiment of the present invention is viewed from the left.FIG.2shows a front portion of the straddle-type vehicle1while a cowl15inFIG.1is transmitted.FIG.3shows a state where the straddle-type vehicle1inFIG.2is viewed from the front.FIG.4shows a state where a cross section of the front portion of the straddle-type vehicle1cut along a cutting line IV-IV inFIG.3is viewed from the left (the right inFIG.3).

The straddle-type vehicle1is, for example, a motorcycle. As shown inFIGS.2and3, the straddle-type vehicle1includes, as elements constituting a vehicle body frame forming a skeleton of the straddle-type vehicle1, a head pipe2and a pair of left and right main frames5extending rearward from the head pipe2. In the head pipe2, a steering stem6which is a steering shaft is supported rotatably around an axis X thereof. Specifically, as shown inFIG.4, the steering stem6is rotatably supported via a bearing4in an inner-cylinder3provided in the head pipe2.

As shown inFIGS.2and3, a front fork7that is a suspension connecting the vehicle body frame and a front wheel10, an upper bracket8that connects an upper end portion of the front fork7to the steering stem6, and a lower bracket9that is located below the upper bracket8and that connects an upper portion of the front fork7to the steering stem6are provided at a front portion of the straddle-type vehicle1.

The upper bracket8extends in a left-right direction, and a steering stem attachment hole is formed in a center of the upper bracket8. An upper end portion of the steering stem6extending upward from the head pipe2is inserted into and fixed to the steering stem attachment hole. A tube attachment portion is provided at each of a left end portion and a right end portion of the upper bracket8, and an upper end portion of a left tube7L of the front fork7is attached to the left tube attachment portion. An upper end portion of a right tube7R of the front fork7is attached to the right tube attachment portion. The lower bracket9extends in the left-right direction, and a lower end portion of the steering stem6extending downward from the head pipe2is inserted into and fixed to a steering stem attachment hole9A formed in a center of the lower bracket9(seeFIG.4). An upper portion of the left tube7L of the front fork7is attached to a tube attachment portion provided at a left end portion of the lower bracket9, and an upper portion of the right tube7R of the front fork7is attached to a tube attachment portion provided at a right end portion of the lower bracket9.

The front wheel10is rotatably supported at a lower end portion of the front fork7. A front fender11that covers the front wheel10from above is provided at a lower portion of the front fork7.

As shown inFIG.2, in the straddle-type vehicle1, a water-cooled engine12, for example, is provided behind the front wheel10, and a radiator13that cools, by traveling wind, cooling water for cooling the engine12and the like is provided between the front wheel10and the engine12.

The straddle-type vehicle1includes the cowl15. In the present embodiment, the cowl15is a so-called full cowl, and includes a front cowl portion16, a pair of left and right side cowl portions17, and an under cowl portion18as shown inFIG.1. The front cowl portion16covers an upper front portion of the straddle-type vehicle1. Specifically, the front cowl portion16is located above the front wheel10, and covers a part from the front of the upper part of the front fork7to the left of a front portion of the left main frame5, and a part from the front of the upper part of the front fork7to the right of a front portion of the right main frame5. The front cowl portion16is a specific example of a “front cowl”. The pair of side cowl portions17cover a left portion and a right portion of the straddle-type vehicle1, specifically, the left and the right of the radiator13and the engine12. The under cowl portion18covers a lower part of the engine12. Although not shown, the cowl15is supported by the head pipe2, the pair of main frames5, and the like via stays or brackets.

Although not shown, a handlebar is attached to an upper portion of the upper bracket8. When a driver operates the handlebar to steer the straddle-type vehicle1, the steering stem6, the upper bracket8, the lower bracket9, the front fork7, the front wheel10, and the front fender11rotate with respect to the head pipe2and the cowl15within a predetermined angle range about the axis X. A caster angle of the straddle-type vehicle1is, for example, approximately 25 degrees, and the head pipe2, the steering stem6, and the front fork7are each inclined at 25 degrees with respect to a vertical straight line such that a lower end portion thereof is located in front of an upper end portion thereof.

As shown inFIG.4, the straddle-type vehicle1includes a shroud21that covers a lower portion of the front cowl portion16, and a lower bracket cover31that covers the lower bracket9from below. The shroud21and the lower bracket cover31are located above a rear portion of the front fender11. The shroud21is formed with an opening27through which the front fork7passes. The opening27corresponds to a space through which the front fork7passes. The opening27of the shroud21is located below the lower bracket9. The lower bracket cover31is provided below the opening27, and covers the entire opening27from below. The lower bracket cover31has a function of suppressing traveling wind passing through the opening27of the shroud21and entering an inside of the front cowl portion16. Hereinafter, the shroud21and the lower bracket cover31will be described in detail.

(Shroud)

FIG.5Ashows a state where the shroud21is viewed from the front.FIG.5Bshows a state where a cross section of the shroud21cut along a cutting line V-V inFIG.5Ais viewed from the left (the right inFIG.5A).FIG.5Cshows a state where the shroud21is viewed from below.

As shown inFIGS.5A to5C, the shroud21includes a front plate portion22, a protruding plate portion23, an upper plate portion24, a rear plate portion25, and a pair of left and right side plate portions26. The front plate portion22extends rearward from a front end portion of the shroud21while gradually expanding to the left and the right. A lower surface of the front plate portion22is substantially horizontal.

The protruding plate portion23protrudes upward from a rear portion of the front plate portion22. A rear surface of a front portion of the protruding plate portion23is inclined in a manner of being parallel to an extending direction of the front fork7. A rear surface of the protruding plate portion23extends in the left-right direction while drawing an arc. Specifically, the rear surface of the protruding plate portion23is formed in an arc shape along a circle C (seeFIG.5C) about the axis X of the steering stem6.

The upper plate portion24extends rearward from an upper portion of the protruding plate portion23while gradually expanding to the left and right. A lower surface of the upper plate portion24is inclined downward from a front end of the upper plate portion24toward the rear in a manner of being orthogonal to the extending direction of the front fork7.

The rear plate portion25extends rearward from a rear portion of the upper plate portion24. A lower surface of the rear plate portion25is inclined slightly upward from a front end of the rear plate portion25toward the rear in a manner of being parallel to an upper surface of the radiator13. The rear plate portion25is located above the radiator13and is in contact with or extremely close to the upper surface of the radiator13(seeFIG.4).

The left side plate portion26is provided on a left portion of the shroud21, and covers an inside of a part from a lower left portion of the front cowl portion16to a front portion of the left side cowl portion17in the cowl15. The right side plate portion26is provided on a right portion of the shroud21, and covers an inside of a part from a lower right portion of the front cowl portion16to a front portion of the right side cowl portion17in the cowl15.

The shroud21has the opening27through which the front fork7passes. The opening27is formed in the upper plate portion24. The opening27penetrates a substantially central portion of the upper plate portion24in the upper-lower direction. The opening27is located below the lower bracket9. As shown inFIG.4, a pair of tubes7L,7R of the front fork7penetrate the opening27. A position and an opening area of the opening27are set such that the front fork7does not come into contact with the shroud21(an edge of the opening27) when the driver operates the handlebar to steer the straddle-type vehicle1and thereby the front fork7rotates.

The front plate portion22of the shroud21is provided with a fixing portion28that fixes the shroud21to the cowl15. Each side plate portion26of the shroud21is provided with a fixing portion29that fixes the shroud21to the cowl15. The shroud21is fixed to the cowl15by attaching the fixing portions28,29to the cowl15using, for example, a fixing member such as a rivet or a screw.

(Lower Bracket Cover)

FIG.6Ashows a state where the lower bracket cover31is viewed from the front.FIG.6Bshows a state where a cross section of the lower bracket cover31cut along a cutting line VI-VI inFIG.6Ais viewed from the left (the right inFIG.6A).FIG.6Cshows a state where the lower bracket cover31is viewed from above.FIG.6Dshows a state where the disassembled lower bracket cover31is viewed from above.FIG.7shows a state where a cross section of the lower bracket9and the lower bracket cover31cut along a cutting line VII-VII inFIG.4is viewed from the front (more accurately, a direction orthogonal to the extending direction of the front fork7).

As shown inFIGS.6A to6C, the lower bracket cover31is formed in a circular plate shape (a chipped circular plate shape) in which a rear end side part is chipped. Further, a front edge of the lower bracket cover31is formed in an arc shape along the circle C (seeFIG.6C) about the axis X of the steering stem6. A radius of an arc of the front edge of the lower bracket cover31is smaller than a radius of an arc of the rear surface of the protruding plate portion23of the shroud21.

A lower surface of a front portion of the lower bracket cover31is flat as a whole. A bent portion32is formed at a rear portion of the lower bracket cover31. A lower surface of the bent portion32is bent upward with respect to the lower surface of the front portion of the lower bracket cover31.

A through hole33is formed in a central portion of the lower bracket cover31. The through hole33is a hole for attaching a stand for floating the front wheel10from the ground for maintenance of the straddle-type vehicle1or the like. A cylindrical portion34extending upward from a peripheral edge portion of the through hole33is formed at the peripheral edge portion of the through hole33. A recess35recessed upward is formed in a rear part of the through hole33in the lower surface of the lower bracket cover31. An inside of the recess35communicates with an inside of the cylindrical portion34. A boundary part between the opening (that is, the through hole33) on a lower side of the cylindrical portion34and the recess35is gently curved as shown inFIG.6B. As a result, a radius of curvature of a corner portion34A on a rear side of the opening on the lower side of the cylindrical portion34is larger than a radius of curvature of a corner portion34B on a front side of the opening.

Two tube insertion holes36through which the pair of tubes7L,7R of the front fork7are inserted are formed in a left portion and a right portion of the lower bracket cover31, respectively. The tube insertion hole36is formed for each tube of the front fork7. The two tube insertion holes36are separated from each other and are independent of each other. On an outer peripheral side of each of the tube insertion holes36, a component insertion hole37through which, for example, a brake hose, a cable, or the like is inserted is formed integrally with the tube insertion hole36. Further, at a peripheral edge portion of the tube insertion hole36and the component insertion hole37, an edge wall38protruding upward is provided over an entire circumference of the peripheral edge portion of the tube insertion hole36and the component insertion hole37.

Attachment portions39configured to attach the lower bracket cover31to the lower bracket9are provided at the left portion and the right portion of the lower bracket cover31, specifically, between the cylindrical portion34and the left tube insertion hole36, and between the cylindrical portion34and the right tube insertion hole36in the lower bracket cover31. Each attachment portion39protrudes upward from the upper surface of the lower bracket cover31. As shown inFIG.7, each attachment portion39is formed in a shape of a covered cylinder. A hole, through which a fixing member40such as a screw passes, is formed in an upper surface of each attachment portion39. The lower bracket cover31is attached to the lower bracket9by fixing an upper end portion of each attachment portion39to a lower surface of the lower bracket9using the fixing member40.

As shown inFIG.6D, the lower bracket cover31is formed by coupling a front cover piece31A and a rear cover piece31B using a fixing member such as a rivet or a screw.

As shown inFIG.4, the lower bracket cover31is provided below the opening27of the shroud21. The lower bracket cover31covers the entire opening27from below the opening27. The lower bracket cover31covers the lower bracket9located above the opening27from below.

The lower bracket cover31is inclined such that an extending direction of the lower surface of the front portion of the lower bracket cover31in a front-rear direction is orthogonal to the extending direction of the front fork7. As a result, the lower surface of the front portion of the lower bracket cover31is inclined downward from a front end portion thereof toward the rear. In a state where the lower surface of the front portion of the lower bracket cover31is inclined as described above, the lower surface of the bent portion32formed at the rear portion of the lower bracket cover31is slightly inclined upward from a front end portion of the lower surface toward the rear. The front portion of the lower bracket cover31is parallel to the upper plate portion24of the shroud21and is close to the upper plate portion24.

The lower bracket cover31is provided behind the protruding plate portion23of the shroud21. A front end of the lower bracket cover31faces the rear surface of the protruding plate portion23. A front end portion of the lower bracket cover31is provided at a position higher than the lower surface of the front plate portion22of the shroud21and lower than a lower surface of a front end portion of the upper plate portion24of the shroud21. A lower surface of a rear end portion of the lower bracket cover31is located substantially in the same plane as the lower surface of the rear plate portion25of the shroud21.

FIG.8Ashows a state where the shroud21and the lower bracket cover31are viewed from above. As can be seen fromFIG.8A, the lower bracket cover31is located below the opening27of the shroud21. An outer peripheral side part of the lower bracket cover31overlaps with a peripheral edge part of the opening27in the upper plate portion24of the shroud21over an entire circumference.FIG.8Billustrates a state where the shroud21and the lower bracket cover31are viewed from below. As can be seen fromFIG.8B, the lower bracket cover31covers the entire opening27of the shroud21from below.

The lower bracket cover31is fixed to the lower bracket9as described above, the lower bracket cover31is not in contact with the shroud21, a center of the arc of the front edge of the lower bracket cover31and a center of the arc of the rear surface of the protruding plate portion23of the shroud21are both located on the axis X of the steering stem6, and the radius of the arc of the front edge of the lower bracket cover31is smaller than the radius of the arc of the rear surface of the protruding plate portion23of the shroud21. According to this configuration, when the driver operates the handlebar to steer the straddle-type vehicle1, the lower bracket cover31rotates about the axis X relative to the shroud21.

In the lower bracket cover31, the through hole33is located below the steering stem6, and the cylindrical portion34extends toward the steering stem6. As shown inFIG.4, the lower end portion (that is, a part of the steering stem6protruding downward from the steering stem attachment hole9A of the lower bracket9) of the steering stem6is inserted into the cylindrical portion34from above. Accordingly, an upper opening of the cylindrical portion34is closed by the lower end portion of the steering stem6.

As shown inFIG.7, each of the tubes7L,7R of the front fork7is inserted into a respective one of the two tube insertion holes36. A brake hose, a cable, or the like is provided in the component insertion hole37. However, when it is not necessary to provide a brake hose, a cable, or the like in the component insertion hole37, as shown inFIG.8A, a sponge41is mounted in the component insertion hole37.

In the straddle-type vehicle1according to the present embodiment having the above configuration, as shown inFIG.4, the lower bracket cover31covers the entire opening27of the shroud21from below. Accordingly, traveling wind W passing between the shroud21and the front fender11during traveling of the straddle-type vehicle1can be suppressed from entering the inside of the front cowl portion16through the opening27of the shroud21. Therefore, it is possible to suppress an increase in air resistance or generation of a front lift caused by the traveling wind W entering the inside of the front cowl portion16through the opening27, and thus it is possible to improve an aerodynamic performance of the straddle-type vehicle1. According to the straddle-type vehicle1, a high aerodynamic performance required for a racing vehicle can be achieved. Further, it is possible to increase an amount of the traveling wind W blowing against the radiator13, and it is possible to improve a cooling effect for the radiator13.

In the straddle-type vehicle1according to the present embodiment, the front end portion of the lower bracket cover31is located above the front plate portion22of the shroud21and faces the rear surface of the protruding plate portion23. That is, the front end portion of the lower bracket cover31is located in a space S (seeFIG.4) surrounded by the protruding plate portion23and the upper plate portion24of the shroud21. Accordingly, the traveling wind W passes under the lower bracket cover31and smoothly flows toward the radiator13. Therefore, it is possible to suppress the traveling wind W from passing between the front end portion of the lower bracket cover31and the shroud21toward the opening27, and it is possible to suppress the traveling wind W from entering the inside of the front cowl portion16through the opening27.

Further, in the straddle-type vehicle1according to the present embodiment, the front edge of the lower bracket cover31and the rear surface of the protruding plate portion23of the shroud21are formed in concentric arc shapes. Therefore, the front edge of the lower bracket cover31and the rear surface of the protruding plate portion23of the shroud21are close to each other over a wide range in a circumferential direction. Accordingly, a gap between the front edge of the lower bracket cover31and the rear surface of the protruding plate portion23can be reduced. Therefore, it is possible to suppress the traveling wind W from passing between the front end portion of the lower bracket cover31and the rear surface of the protruding plate portion23toward the opening27, and it is possible to suppress the traveling wind W from entering the inside of the front cowl portion16through the opening27.

In the lower bracket cover31, the tube insertion hole36is formed for each tube of the front fork7. That is, the lower bracket cover31is not formed with one large hole through which the two tubes7L,7R of the front fork7collectively pass, but is formed with two small holes through which the two tubes7L,7R of the front fork7individually pass. Accordingly, a gap between the left tube insertion hole36and an outer peripheral surface of the tube7L and a gap between the right tube insertion hole36and an outer peripheral surface of the tube7R can be reduced. Therefore, it is possible to suppress the traveling wind W from blowing toward the opening27through the tube insertion hole36, and it is possible to suppress the traveling wind W from entering the inside of the front cowl portion16through the opening27.

When it is not necessary to provide a brake hose, a cable, or the like in the component insertion hole37of the lower bracket cover31, the component insertion hole37is filled with the sponge41and is closed. Accordingly, it is possible to suppress the traveling wind W from blowing toward the opening27through the component insertion hole37, and it is possible to suppress the traveling wind W from entering the inside of the front cowl portion16through the opening27.

The lower surface of the front portion of the lower bracket cover31is inclined downward from the front end portion of the lower surface toward the rear, the lower surface of the bent portion32formed at the rear portion of the lower bracket cover31is gently curved upward, and a lower surface of a rear end portion of the bent portion32is slightly inclined upward toward the rear. The rear end portion of the lower bracket cover31is located substantially in the same plane as the rear plate portion25of the shroud21. Accordingly, a continuous surface having less unevenness is formed from the lower surface of the front portion of the lower bracket cover31to the lower surface of the rear plate portion25of the shroud21. According to this configuration, the traveling wind W can be smoothly guided to the radiator13, and the amount of the traveling wind W blowing against the radiator13can be increased.

The cylindrical portion34extending from the peripheral edge portion of the through hole33of the lower bracket cover31to the lower end portion of the steering stem6is provided at the peripheral edge portion of the through hole33. Further, the upper opening of the cylindrical portion34is closed by the lower end portion of the steering stem6entering the opening. According to this configuration, it is possible to suppress the traveling wind W from entering the inside of the front cowl portion16through the through hole33of the lower bracket cover31.

The recess35recessed upward is formed in a rear part of the through hole33in the lower surface of the lower bracket cover31, and the inside of the recess35communicates with the inside of the cylindrical portion34. Accordingly, it is possible to suppress the traveling wind W from flowing into the cylindrical portion34through the through hole33of the lower bracket cover31, and it is possible to reduce air resistance formed by the lower bracket cover31.

In the straddle-type vehicle1according to the present embodiment, the lower bracket cover31is provided below the upper plate portion24and the opening27of the shroud21. Therefore, even when a distance between the lower bracket9and the shroud21in the upper-lower direction is increased due to design of the straddle-type vehicle1, a vehicle setting during racing, or the like, the lower bracket cover31can be provided below the upper plate portion24and the opening27of the shroud21in a state of being close to the upper plate portion24and the opening27, and the opening27can be reliably covered by the lower bracket cover31. Therefore, an effect of the lower bracket cover31of suppressing the traveling wind W from entering the inside of the front cowl portion16through the opening27can be suppressed from being lowered due to an increase in the distance between the lower bracket9and the shroud21in the upper-lower direction due to the design of the straddle-type vehicle1or the like. When the distance between the lower bracket9and the shroud21in the upper-lower direction is increased due to the design of the straddle-type vehicle1or the like, a position of the lower bracket cover31can be easily lowered by providing a spacer between the lower surface of the lower bracket9and the upper surface of each attachment portion39of the lower bracket cover31.

Since the lower bracket cover31is provided below the upper plate portion24and the opening27of the shroud21, even when the distance between the lower bracket9and the shroud21in the upper-lower direction is extremely small due to the design of the straddle-type vehicle1or the like, the lower bracket cover31can be provided below the opening27, and the opening27can be covered by the lower bracket cover31.

The front fork7of the straddle-type vehicle1according to the above-described embodiment is of an inverted type. However, the present invention can also be applied to a straddle-type vehicle including a front fork of an upright type. In the straddle-type vehicle1according to the above-described embodiment, the radiator13is provided behind the front wheel10, and the traveling wind W is guided to the radiator13. However, an oil cooler may be provided behind the front wheel10, and the traveling wind W may be guided to the oil cooler. When the engine of the straddle-type vehicle is an air-cooled engine, the traveling wind W may be guided to the air-cooled engine provided behind the front wheel10. In the present invention, a type of the cowl of the straddle-type vehicle is not limited. The straddle-type vehicle according to the present invention is not limited to a motorcycle, but may be another type of straddle-type vehicle. Further, the straddle-type vehicle according to the present invention is not limited to a racing vehicle.

The present invention can be modified as appropriate without departing from the spirit or concept of the invention that can be read from the claims and the entire description, and the straddle-type vehicle accompanying such a modification is also included in the technical concept of the present invention.