VEHICLE

Abstract

A vehicle including: a body frame; a seat provided on the body frame; a pair of front wheels provided at a front portion of the body frame; a pair of rear wheels provided at a rear portion of the body frame; a rear gear provided between the pair of rear wheels; a drive source provided below the seat; and a pair of suspensions each including an upper arm and a lower arm, and respectively supporting the pair of rear wheels. The lower arm in each of the suspensions includes: a front arm portion, connected with the body frame at a position more forward than a rear end of the drive source in a fore-aft direction of the vehicle, and a rear arm portion, connected with the body frame at a position more rearward than a center of the rear gear in the fore-aft direction of the vehicle.

Description

CROSS REFERENCE TO RELATED APPLICATIONS

This application is based upon and claims the benefit of priority of the prior Japanese Patent Application No. 2023-059554, filed on Mar. 31, 2023, the entire contents of which are incorporated herein by reference.

BACKGROUND OF THE INVENTION

Field of the Invention

The present invention relates to vehicles, and more specifically to a straddled vehicle such as an ATV (All Terrain Vehicle).

Description of the Related Art

As an example of conventional techniques of this kind, U.S. Pat. No. 7,770,907 discloses a straddled vehicle. The vehicle includes a lower pipe; a rear pipe extending upward from a rear end of the lower pipe; a rear suspension arm support pipe connecting the lower pipe and the rear pipe; and a rear wheel suspension supporting a rear wheel. The rear wheel suspension connects a rear portion of the lower pipe with a rear portion of the rear suspension arm support pipe. The rear wheel suspension includes a lower arm having a front arm portion and a back arm portion and connected with a rear portion of the lower pipe; an upper arm connected with the rear suspension arm support pipe; and a rear wheel shock absorber disposed between the back arm portion of the lower arm and the rear pipe.

In the vehicle, the front arm portion and the back arm portion of the lower arm are slanted with respect to the lower pipe, at substantially the same angle as each other and then connected with the lower pipe. In other words, the front arm portion and the back arm portion have their respective end portions not very much spaced from each other at the place where they are connected with the lower pipe. Therefore, there is room for improvement in increasing an arm span of the lower arm thereby reducing stress on the lower arm and the lower pipe.

SUMMARY OF THE INVENTION

Therefore, a primary object of the present invention is to provide a vehicle in which stress on a lower arm and a body frame is reduced, and the lower arm and the body frame can be lighter.

According to an aspect of the present invention, there is provided a vehicle including a body frame; a saddle-style seat provided in the body frame; a pair of front wheels provided in a front portion of the body frame; a pair of rear wheels provided in a rear portion of the body frame; a rear gear provided between the pair of rear wheels; a drive source provided below the seat; and a suspension having an upper arm and a lower arm and supporting the rear wheel. The lower arm includes a front arm portion connected with the body frame at a position more forward than a rear end of the drive source in a fore-aft direction in a side view; and a rear arm portion connected with the body frame at a position more rearward than a center of the rear gear in a fore-aft direction in a side view.

In the present invention, in regards of the lower arm on the rear-wheel side suspension, the front arm portion is connected with the body frame at a position more forward than a rear end of the drive source in a fore-aft direction in a side view while the rear arm portion is connected with the body frame at a position more rearward than the center of the rear gear in a fore-aft direction in a side view. As described, the front arm portion is extended to a side of the drive source, so that the connection point where the front arm portion is connected with the body frame is located ahead. Also, the front arm portion and the rear arm portion are connected with the body frame in such a form that, in a plan view, both of them are opening with respect to a straight line which connects the centers of the pair of rear wheels. In other words, the front arm portion and the rear arm portion are slanted in a fore-aft direction with respect to the straight line which connects the centers of the pair of rear wheels. This makes it possible to increase an arm span of the lower arm, thereby decreasing stress on the lower arm and the body frame, and to decrease the weight of the lower arm and the body frame.

Preferably, the rear arm portion is connected with the body frame at a position more forward than a rear end of the rear gear in a fore-aft direction in a side view. In this case, it becomes possible to reduce scraping the bottom of the vehicle, i.e., the vehicle rubbing the ground with its bottom.

Further preferably, the front arm portion's point of connection with the body frame is more outboard than a point of connection where the rear arm portion is connected with the body frame. In this case, it becomes easy to slant the lower arm's pivot axis opening forward, making it easy to dispose the drive source at a rear position.

Further, preferably, the lower arm's pivot axis slants with respect to the vehicle's fore-aft direction in a plan view, having a front portion thereof opening outward. In this case, the lower arm's pivot axis slants to open forward, and it becomes easy to dispose the drive source at a rear position.

Preferably, the body frame includes a frame intermediate portion, and a frame rear portion extending rearward from the frame intermediate portion with its span in the vehicle's width direction becoming narrower than that of the frame intermediate portion, and the front arm portion is connected with the frame intermediate portion. In this case, it becomes possible to position the connection point where the front arm portion is connected with the body frame at a forward location, making it possible to increase the arm span of the lower arm.

Further preferably, the rear arm portion is connected with the frame rear portion. In this case, it becomes possible to position the connection point where the rear arm portion is connected with the body frame at a rearward location, making it possible to increase the arm span of the lower arm.

Further, preferably, the vehicle further includes a connection bracket extending in an up-down direction to connect the rear arm portion with the upper arm, and the connection bracket has its inboard side carved so as not to make contact with the rear gear. In this case, it becomes possible to secure appropriate length of the upper arm and of the lower arm, making it easy to assemble the rear gear.

Preferably, the suspension further includes a shock absorber connecting the body frame with the lower arm. In this case, it becomes possible to use a long shock absorber by connecting the shock absorber with the lower arm.

Further preferably, the shock absorber is ahead of the upper arm.

Further, preferably, the upper arm is formed in a bent shape to detour the shock absorber. In this case, it becomes easy to dispose the shock absorber ahead of the upper arm.

Preferably, the front arm portion has a bent portion, and the shock absorber is connected with the lower arm near the bent portion.

Further preferably, the lower arm further includes a reinforcing member connecting the bent portion with the rear arm portion, and the shock absorber is connected with the reinforcing member.

The above-described object and other objects, characteristics, aspects and advantages of the present invention will become clearer from the following detailed description of embodiments of the present invention to be made with reference to the attached drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a side view which shows a vehicle according to an embodiment of the present invention.

FIG. 2 is a plan view which shows the vehicle in FIG. 1.

FIG. 3 is a bottom view which shows the vehicle in FIG. 1.

FIG. 4 is a front view which shows the vehicle in FIG. 1.

FIG. 5 is a rear view which shows the vehicle in FIG. 1.

FIG. 6 is a side view which shows a state where wheels, a front fender, etc. are removed from the vehicle in FIG. 1.

FIG. 7 is a plan view which shows a state where the wheels, the front fender, etc. are removed from the vehicle in FIG. 1.

FIG. 8 is a bottom view which shows a state where the wheels, the front fender, etc. are removed from the vehicle in FIG. 1.

FIG. 9 is a front view which shows a state where the wheels, the front fender, etc. are removed from the vehicle in FIG. 1.

FIG. 10 is a rear view which shows a state where the wheels, the front fender, etc. are removed from the vehicle in FIG. 1.

FIG. 11 is a plan view which shows an inside structure of the vehicle in FIG. 1.

FIG. 12 is a sectional view taken in a line A-A in FIG. 11.

FIG. 13 is a side view which shows a suspension and surrounds thereof on a rear-wheel side.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

In the drawings, “Fr” indicates forward, “Rr” indicates rearward, “R” indicates rightward, “L” indicates leftward, “U” indicates upward and “Lo” indicates downward.

Referring to FIG. 1 through FIG. 5, a vehicle 10 according to an embodiment of the present invention is a straddled vehicle, and more specifically a four-wheeled ATV, which includes a body frame 12, a pair of front wheels 14a, 14b, a pair of rear wheels 16a, 16b, a bar handle 18, a saddle-style seat 20, and a pair of footrests 22a, 22b.

Referring also to FIG. 6 through FIG. 10, the body frame 12 includes a frame intermediate portion 12a, and a frame rear portion extending rearward from the frame intermediate portion 12a with a gradually narrower span in a with direction of the vehicle than the frame intermediate portion 12a. The pair of front wheels 14a, 14b are provided at a front portion of the body frame 12 via a pair of suspensions 62a, 62b (which will be described later). The pair of rear wheels 16a, 16b are provided at a rear portion of the body frame 12 via a pair of suspensions 64a, 64b (which will be described later). The bar handle 18 is provided in an intermediate region in the vehicle's width direction, connected at an upper portion of a steering shaft 58 (which will be described later), above the front wheels 14a, 14b in a side view. The seat 20 is provided at an intermediate portion in the vehicle's width direction, at a higher position than the front wheels 14a, 14b and the rear wheels 16a, 16b, between the front wheels 14a, 14b and the rear wheels 16a, 16b in a side view, and is supported by the body frame 12. The pair of footrests 22a, 22b, serving as places where the rider puts his/her respective feet, are provided in the body frame 12, disposed between the front wheels 14a, 14b and the rear wheels 16a, 16b in a side view.

Referring to FIG. 11 and FIG. 12, the vehicle 10 further includes an engine 24 as a prime mover, a continuously variable transmission 26, and a transmission 28. The engine 24, the continuously variable transmission 26 and the transmission 28 are provided in the body frame 12.

In the present embodiment, the engine 24 is provided by a parallel two-cylinder engine, which is installed below the seat 20. The engine 24 is disposed at a place slightly rearward than a center portion in a fore-aft direction of the body frame 12, with a rearward tilt. In other words, the engine 24 is laid in a rear-midship style. The continuously variable transmission 26, which receives an output from the engine 24, is provided on an outer side (left side in the present embodiment) of the engine 24. The transmission 28 is provided ahead of the engine 24 in order to speed-change an output from the continuously variable transmission 26. Therefore, the engine 24 and the transmission 28 are connected with each other via the continuously variable transmission 26.

The vehicle 10 further includes a propeller shaft 30 connected with the transmission 28 and extending in a fore-aft direction; a front shaft 32 connected with a front end portion of the propeller shaft 30 and extending in a fore-aft direction; a rotation transmission portion 34 (see FIG. 8) which transmits rotation coming from the transmission 28 via the propeller shaft 30 and the front shaft 32 to the pair of front wheels 14a, 14b; a rear shaft (not illustrated) connected with a rear end portion of the propeller shaft 30 and extending in a fore-aft direction; and a rotation transmission portion 36 which transmits rotation coming from the transmission 28 via the propeller shaft 30 and the rear shaft to the pair of rear wheels 16a, 16b. The rotation transmission portion 36 includes a rear gear 38, and a pair of drive shafts 40a, 40b (see FIG. 10). The rear gear 38 is provided between the pair of rear wheels 16a, 16b. The rear gear 38 receives rotation of the rear shaft. The pair of drive shafts 40a, 40b are provided between the rear gear 38 and the respective one of the pair of rear wheels 16a, 16b. Therefore, rotation of the rear gear 38 is transmitted to the pair of rear wheels 16a, 16b via the pair of drive shafts 40a, 40b.

The rotation transmission portion 34 is connected with the engine 24 via the front shaft 32, the propeller shaft 30, the transmission 28 and the continuously variable transmission 26. The rotation transmission portion 36 is connected with the engine 24 via the rear shaft, the propeller shaft 30, the transmission 28 and the continuously variable transmission 26. Therefore, rotation of the engine 24 undergoes speed changes performed by the continuously variable transmission 26 and the transmission 28, and then is transmitted to the pair of front wheels 14a, 14b via the propeller shaft 30, the front shaft 32, and the rotation transmission portion 34. This rotates the pair of front wheels 14a, 14b. Also, rotation of the engine 24 undergoes speed changes performed by the continuously variable transmission 26 and the transmission 28, and then is transmitted to the pair of rear wheels 16a, 16b via the propeller shaft 30, the rear shaft, and the rotation transmission portion 36. This rotates the pair of rear wheels 16a, 16b.

The vehicle 10 further includes an air intake pipe 42 connected with the engine 24 in order to supply air into the engine 24, an air cleaner 44 connected with the air intake pipe 42, an exhaust pipe 46 connected with the engine 24 to discharge exhaust from the engine 24, and a muffler 48 connected with the exhaust pipe 46.

The air cleaner 44 is provided ahead of the engine 24 to overlap with the engine 24 in a front view, below the seat 20. The muffler 48 is provided behind the engine 24. The air intake pipe 42 is connected with a front portion of the engine 24. The exhaust pipe 46 is connected with a rear portion of the engine 24. Therefore, the engine 24 has a structure called front intake rear exhaust.

The vehicle 10 further includes a fuel tank 50 which holds fuel to be supplied to the engine 24, and a battery 52 and an electric box 54 which are provided above the fuel tank 50.

The fuel tank 50 is provided at a position diagonally forward and upward of the transmission 28, ahead of the air cleaner 44. The battery 52 and the electric box 54 are provided side by side ahead of the seat 20.

The vehicle 10 further includes a steering mechanism 56 for steering the pair of front wheels 14a, 14b.

The steering mechanism 56 includes the steering shaft 58, and an electric power steering (EPS) 60 provided on the steering shaft 58. The steering shaft 58 is provided ahead of the seat 20. The electric power steering 60 is provided ahead of the fuel tank 50.

The vehicle 10 further includes the pair of suspensions 62a, 62b which are provided in the body frame 12 and suspend the pair of front wheels 14a, 14b; and the pair of suspensions 64a, 64b which are provided in the body frame 12 and suspend the pair of rear wheels 16a, 16b.

Referring to FIG. 6 through FIG. 8 and FIG. 10, the pair of suspensions 64a, 64b include shock absorbers 66a, 66b; springs 68a, 68b; reservoir tanks 70a, 70b; upper arms 72a, 72b; lower arms 74a, 74b; and knuckles 76a, 76b, respectively.

The springs 68a, 68b are fitted around the outer circumferences of the shock absorbers 66a, 66b respectively. The shock absorbers 66a, 66b have their respective upper end portions connected with the reservoir tanks 70a, 70b. The upper arms 72a, 72b are respectively connected pivotably with the body frame 12. The lower arms 74a, 74b are respectively placed below the upper arms 72a, 72b, and connected pivotably with the body frame 12. The knuckles 76a, 76b connect the upper arms 72a, 72b with the lower arms 74a, 74b, respectively. The shock absorbers 66a, 66b are provided ahead of the upper arms 72a, 72b and connect the body frame 12 with the lower arms 74a, 74b respectively. The upper arms 72a, 72b are formed in a bent shape to detour (or accommodate) the shock absorbers 66a, 66b respectively.

The lower arms 74a, 74b include front arm portions 78a, 78b and rear arm portions 80a, 80b respectively.

Referring to FIG. 8 and FIG. 13, the front arm portions 78a, 78b are connected with the body frame 12 at positions more forward than a rear end B of the engine 24 in a fore-aft direction in a side view. The front arm portions 78a, 78b are connected with the frame intermediate portion 12a. The rear arm portions 80a, 80b are connected with the body frame 12 at positions more rearward than a center C of the rear gear 38 but more forward than a rear end D of the rear gear 38 in a fore-aft direction in a side view. The rear arm portions 80a, 80b are connected with the frame rear portion 12b. The points of connection E1, E2 where the front arm portions 78a, 78b are connected with the body frame 12 are more outboard than the points of connection F1, F2 where the rear arm portions 80a, 80b are connected with the body frame 12 respectively. Therefore, the lower arms 74a, 74b have their respective hypothetical pivot axes G1, G2, slanted, with respect to the vehicle's fore-aft direction in a plan view, having their front portions opening outward. The lower arms 74a, 74b can swing around the pivot axes G1, G2, respectively, relative to the body frame 12.

The front arm portions 78a, 78b have bent portions 82a, 82b respectively. The lower arms 74a, 74b further include reinforcing members 84a, 84b connecting the bent portions 82a, 82b with the rear arm portions 80a, 80b respectively. The shock absorbers 66a, 66b are connected with the lower arms 74a, 74b near the bent portions 82a, 82b respectively; more specifically, connected with the reinforcing members 84a, 84b.

Referring to FIG. 10, the rear arm portions 80a, 80b and the upper arms 72a, 72b are connected with each other with connection brackets 86a, 86b extending in an up-down direction respectively. In order not to make contact with the rear gear 38, the connection brackets 86a, 86b have their respective inboard sides H1, H2 carved.

Returning to FIG. 1 through FIG. 5, the vehicle 10 further includes a front fender 88 and a rear fender 90. The front fender 88 is provided above the pair of front wheels 14a, 14b, striding over the pair of front wheels 14a, 14b, in a plan view. The rear fender 90 is provided above the pair of rear wheels 16a, 16b, striding over the pair of rear wheels 16a, 16b, in a plan view.

According to the vehicle 10 as has been described thus far, in regards of the lower arms 74a, 74b on the rear-wheel side suspensions 64a, 64b, the front arm portions 78a, 78b are connected with the body frame 12 at positions more forward than the rear end B of the engine 24 in a fore-aft direction in a side view while the rear arm portions 80a, 80b are connected with the body frame 12 at positions more rearward than the center C of the rear gear 38 in a fore-aft direction in a side view. As described, the front arm portions 78a, 78b are extended to sides of the engine 24, so that the connection points E1, E2 where the front arm portions 78a, 78b are connected with the body frame 12 are located ahead. Also, the front arm portions 78a, 78b and the rear arm portions 80a, 80b are connected with the body frame 12 in such a form that, in a plan view, both of them are opening with respect to a straight line P (see FIG. 8) which connects centers of the pair of rear wheels 16a, 16b. In other words, the front arm portions 78a, 78b and the rear arm portions 80a, 80b are slanted in a fore-aft direction with respect to the straight line P which connects the centers of the pair of rear wheels 16a, 16b. This makes it possible to increase an arm span S (see FIG. 13) of the lower arms 74a, 74b, thereby decreasing stress on the lower arms 74a, 74b and the body frame 12, and to decrease the weight of the lower arms 74a, 74b and the body frame 12.

The rear arm portions 80a, 80b are connected with the body frame 12 at positions more forward than the rear end D of the rear gear 38 in a fore-aft direction in a side view. This makes it possible to reduce scraping the bottom of the vehicle 12, i.e., vehicle 12 rubbing the ground with its bottom.

The points of connection E1, E2 where the front arm portions 78a, 78b are connected with the body frame 12 are more outboard than the points of connection F1, F2 where the rear arm portions 80a, 80b are connected with the body frame 12. Therefore, it becomes easy to slant the lower arms 74a, 74b so that their pivot axes G1, G2 have their front portions opening outward, making it easy to dispose the engine 24 at a rear position.

Since the lower arms 74a, 74b are slanted with respect to the vehicle's fore-aft direction so that their pivot axes G1, G2 have their front portions open outward in a plan view, the pivot axes G1, G2 of the lower arms 74a, 74b slant to open forward, making it easy to dispose the engine 24 at a rear position.

The front arm portions 78a, 78b are connected with the frame intermediate portion 12a. This makes it possible to position the connection points E1, E2 where the front arm portions 78a, 78b are connected with the body frame 12 at forward locations, making it possible to increase the arm span S of the lower arms 74a, 74b.

The rear arm portions 80a, 80b are connected with the frame rear portion 12b. This makes it possible to position the connection points F1, F2 where the rear arm portions 80a, 80b are connected with the body frame 12 at rearward locations, making it possible to increase the arm span S of the lower arms 74a, 74b.

The connection brackets 86a, 86b have their respective inboard sides H1, H2 carved so as not make contact with the rear gear 38. This makes it possible to secure appropriate length of the upper arm and of the lower arm, making it easy to assemble the rear gear 38.

By connecting the shock absorbers 66a, 66b with the lower arms 74a, 74b, it becomes possible to use long shock absorbers.

The upper arms 72a, 72b are formed in a bent shape to detour the shock absorbers 66a, 66b. This makes it easy to dispose the shock absorbers 66a, 66b ahead of the upper arms 72a, 72b.

In the embodiment described above, the prime mover is provided by the engine 24. However, the invention is not limited to this. The prime mover may be provided by a motor.

The present invention being thus far described in terms of preferred embodiments, it is obvious that these may be varied in many ways within the scope and the spirit of the present invention. The scope of the present invention is limited only by the accompanied claims.

Claims

1. A vehicle comprising: a body frame;a seat provided on the body frame;a pair of front wheels provided at a front portion of the body frame;a pair of rear wheels provided at a rear portion of the body frame;a rear gear provided between the pair of rear wheels;a drive source provided below the seat; anda pair of suspensions respectively supporting the pair of rear wheels, each suspension including an upper arm and a lower arm, the lower arm including: a front arm portion, connected with the body frame at a position more forward than a rear end of the drive source in a fore-aft direction of the vehicle, anda rear arm portion, connected with the body frame at a position more rearward than a center of the rear gear in the fore-aft direction of the vehicle.

2. The vehicle according to claim 1, wherein the rear arm portion of said lower arm is connected with the body frame at a position more forward than a rear end of the rear gear in the fore-aft direction of the vehicle.

3. The vehicle according to claim 1, wherein a connection point of the front arm portion of said lower arm with the body frame is more outboard than a connection point of the rear arm portion of said lower arm with the body frame.

4. The vehicle according to claim 1, wherein said lower arm has a pivot axis, which is slanted with respect to the fore-aft direction of the vehicle so that a front portion of the pivot axis is opening outward.

5. The vehicle according to claim 1, wherein the body frame includes: a frame intermediate portion, anda frame rear portion extending rearward from the frame intermediate portion, a span of the frame rear portion in the width direction of the vehicle becoming gradually narrower as the frame rear portion extends rearward, andthe front arm portion of said lower arm is connected with the frame intermediate portion.

6. The vehicle according to claim 5, wherein the rear arm portion of said lower arm is connected with the frame rear portion.

7. The vehicle according to claim 1, further comprising a pair of connection brackets extending in an up-down direction of the vehicle to respectively connect the pair of rear arm portions with the pair of upper arms, wherein each of the connection brackets has an inboard side thereof carved to have a clearance with the rear gear.

8. The vehicle according to claim 1, wherein each of the suspensions further includes a shock absorber connecting the body frame with the lower arm of said each suspension.

9. The vehicle according to claim 8, wherein in said each suspension, the shock absorber is positioned ahead of the upper arm.

10. The vehicle according to claim 9, wherein in said each suspension, the upper arm is formed in a bent shape to accommodate the shock absorber.

11. The vehicle according to claim 8, wherein in said each suspension, the front arm portion has a bent portion, andthe shock absorber is connected with the lower arm at the bent portion.

12. The vehicle according to claim 11, wherein in said each suspension, the lower arm further includes a reinforcing member connecting the bent portion with the rear arm portion, andthe shock absorber is connected with the reinforcing member.

13. The vehicle according to claim 1, wherein the pair of lower arms each have a pivot axis, andthe two pivot axes are so slanted with respect to the fore-aft direction of the vehicle as to converge behind the pair of lower arms.