Rear wheel suspension

Abstract

To suppress an influence of heat from muffler piping on components of a vehicle height adjusting device.SOLUTION: A rear wheel suspension device (30) is provided with a swing arm (31) supported so as to rock with respect to a vehicle body frame (10). The rear wheel suspension device is provided with a rear cushion (33) expanding / contracting with the rocking of the swing arm, a cushion lever (34) coupled to a lower end portion of the rear cushion, a cushion rod (35) coupling the cushion lever and the swing arm, and accumulator (51) storing working fluid expanding / contracting the cushion rod, and an accumulator bracket (82) that supports the accumulator. Muffler piping (90) extends backward through a side part of the accumulator from an engine (15), and the accumulator bracket partitions the accumulator and the muffler piping.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to a rear wheel suspension system. [Background technology]

[0002] Conventionally, straddle-type vehicles have adopted a swing arm type rear wheel suspension (rear suspension) (see, for example, Patent Document 1). In the rear wheel suspension described in Patent Document 1, a swing arm is swingably supported on the body frame, and the rear wheel is rotatably supported at the rear end of the swing arm. A rear cushion is connected to the swing arm via a link mechanism, and unevenness in the road surface is absorbed by the rear cushion. In recent years, such rear wheel suspensions of straddle-type vehicles may be additionally equipped with a vehicle height adjustment device called a ride height adjuster or the like. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Laid-Open No. 2003-104266 Summary of the Invention [Problem to be solved by the invention]

[0004] Due to space limitations in straddle-type vehicles, components for vehicle height adjustment devices are often placed high up on the vehicle, but considering vehicle stability, it is desirable to place them low down on the vehicle body so as not to raise the center of gravity. However, because the muffler piping is located below the vehicle body, there is a problem in that the components for the vehicle height adjustment device are affected by heat.

[0005] SUMMARY OF THE INVENTION The present invention has been made in view of the above points, and an object of the present invention is to provide a rear wheel suspension system that can suppress the influence of heat from the muffler piping on the components of a vehicle height control system. [Means for solving the problem]

[0006] A rear wheel suspension device of one aspect of the present invention is a rear wheel suspension device comprising a swing arm that is swingably supported on a body frame, with a rear wheel rotatably supported on the swing arm, the rear wheel suspension device comprising: a rear cushion that expands and contracts as the swing arm swings; a cushion lever connected to the lower end of the rear cushion; a cushion rod that connects the cushion lever and the swing arm; an accumulator that stores working fluid that expands and contracts the cushion rod; and an accumulator bracket that supports the accumulator, wherein the vehicle height is adjusted by displacement of the swing arm as the cushion rod expands and contracts, and muffler piping extends rearward from the engine, passing beside the accumulator, and the accumulator bracket separates the accumulator from the muffler piping, thereby solving the above-mentioned problems. [Effects of the Invention]

[0007] In a rear wheel suspension device according to one aspect of the present invention, vehicle height is adjusted by extending and retracting the cushion rod using the working fluid in the accumulator. Lowering the rear vehicle height when starting or exiting a corner allows for stable acceleration with a low center of gravity. Furthermore, an accumulator bracket is positioned between the accumulator and the muffler piping, protecting the accumulator from the heat of the muffler piping. [Brief explanation of the drawings]

[0008] [Figure 1] 1 is a left side view of a saddle-ride type vehicle according to an embodiment of the present invention; [Figure 2] FIG. 2 is a left side view of the rear wheel suspension device of the present embodiment. [Figure 3] FIG. 2 is a bottom view of the rear wheel suspension device of the present embodiment. [Figure 4] 4 is a cross-sectional view of the rear wheel suspension device of FIG. 3 taken along line AA. [Figure 5] 1 is a schematic diagram of a vehicle height adjusting device according to an embodiment of the present invention; [Figure 6] 1 is a side view of the vicinity of the vehicle height adjusting device of the present embodiment. [Figure 7] 7 is a cross-sectional view of the vehicle height adjusting device of FIG. 6 taken along line BB. [Figure 8] 7 is a cross-sectional view of the vehicle height adjusting device of FIG. 6 taken along line CC. DETAILED DESCRIPTION OF THE INVENTION

[0009] In one aspect of the rear wheel suspension of the present invention, a swing arm is swingably supported on a vehicle body frame, and a rear wheel is rotatably supported on the swing arm. The rear cushion expands and contracts as the swing arm swings, absorbing unevenness in the road surface. A cushion lever is connected to the lower end of the rear cushion, and the cushion lever and the swing arm are connected by a cushion rod. The cushion rod expands and contracts with a working fluid, and the working fluid is stored in an accumulator. The cushion rod expands and contracts with the working fluid in the accumulator, and vehicle height is adjusted by the displacement of the swing arm as the cushion rod expands and contracts. Lowering the rear vehicle height during starts and cornering enables stable acceleration with a low center of gravity. Furthermore, a muffler piping extends rearward from the engine, passing beside the accumulator, and an accumulator bracket separates the accumulator from the muffler piping. The accumulator bracket protects the accumulator from the hot air in the muffler piping. [Example]

[0010] This embodiment will be described in detail below with reference to the accompanying drawings. Fig. 1 is a left side view of a saddle-ride type vehicle according to this embodiment. In the following drawings, arrow FR indicates the front of the vehicle, arrow RE indicates the rear of the vehicle, arrow L indicates the left side of the vehicle, and arrow R indicates the right side of the vehicle.

[0011] As shown in Figure 1, a saddle-type vehicle 1 is configured by mounting an engine 15, an electrical system, and other components on a body frame 10 formed of pipes and sheet metal. A main frame 14 branches into left and right sections and extends rearward from a head pipe 11 of the body frame 10. The front portion of the main frame 14 forms a tank rail 12 located above the engine 15, and a fuel tank (not shown) is supported from below by the tank rail 12. The rear portion of the main frame 14 forms a pivot frame 13 located behind the engine 15, and a swing arm 31 is supported by the pivot frame 13 so that it can swing.

[0012] A front fork 19 is steerably supported on the head pipe 11 via a steering shaft (not shown). A front wheel 21 is rotatably supported on the lower part of the front fork 19, and an upper part of the front wheel 21 is covered by a front fender 22. A swing arm 31 extends rearward from the pivot frame 13. A rear wheel 25 is rotatably supported on the rear end of the swing arm 31, and a front part of the rear wheel 25 is covered by a rear fender 26. An engine 15 is connected to the rear wheel 25 via a chain drive type transmission mechanism, and power from the engine 15 is transmitted to the rear wheel 25 via the transmission mechanism.

[0013] Furthermore, a vehicle height adjustment device 50 (see FIG. 2) is attached to the rear wheel suspension 30 of the saddle-riding vehicle 1, which lowers the center of gravity of the vehicle by adjusting the vehicle height, with the aim of increasing the wheelie limit and improving acceleration. The vehicle height adjustment device 50 is provided with an accumulator 51 (see FIG. 2) that stores oil (working fluid) for adjusting the vehicle height. The accumulator 51 is often placed inside the seat cowl or to the side of the body frame 10, but if a heavy object such as the accumulator 51 is placed above the vehicle, it is not possible to sufficiently lower the center of gravity. Therefore, in the rear wheel suspension 30 of this embodiment, space is secured below the swing shaft 32 of the swing arm 31 to place the accumulator 51.

[0014] A rear wheel suspension of a saddle-ride type vehicle will be described with reference to Figures 2 to 5. Figure 2 is a left side view of the rear wheel suspension of this embodiment. Figure 3 is a bottom view of the rear wheel suspension of this embodiment. Figure 4 is a cross-sectional view of the rear wheel suspension of Figure 3 taken along line AA. Figure 5 is a schematic diagram of a vehicle height adjustment device of this embodiment. For ease of explanation, in Figure 2, the body frame and swing arm are indicated by two-dot chain lines. Figure 5(A) shows the link rod in an extended state, and Figure 5(B) shows the link rod in a retracted state.

[0015] As shown in Figure 2, a swing arm type rear wheel suspension device 30 is attached to the engine 15 and the pivot frame 13. A double-sided swing arm 31 is swingably supported via a swing shaft 32 at the midpoint in the height direction of the pivot frame 13. The swing arm 31 is connected to the engine 15 and the pivot frame 13 via a rear cushion 33, a cushion lever 34, and a cushion rod 35. The rear cushion 33 expands and contracts as the swing arm 31 swings, absorbing unevenness in the road surface and suppressing vibrations while improving the contact between the road surface and the rear wheel 25.

[0016] The upper end of a rear cushion 33 is supported by the engine 15 and the upper part of the pivot frame 13, and the rear top of a cushion lever 34, which is generally triangular in side view, is connected to the lower end of the rear cushion 33. The front top of the cushion lever 34 is connected to the lower part of the pivot frame 13, and the lower top of the cushion lever 34 (see FIG. 4) is connected to the lower part of the swing arm 31 via an extendable cushion rod 35. As the swing arm 31 swings, the cushion lever 34 swings around the front top as a fulcrum, and impacts from the road surface, etc. are transmitted from the swing arm 31 to the rear cushion 33.

[0017] An accumulator bracket 82 is attached to the bottom of the engine 15 via a suspension bracket 81. The accumulator bracket 82 supports an accumulator 51, which stores oil that extends and retracts the cushion rod 35. The accumulator 51 is provided with a plunger switch 52, and the cushion rod 35 is connected to the plunger switch 52 via a connecting hose 53. The plunger switch 52 controls the movement of oil inside the connecting hose 53. An operating unit (not shown) is connected to the plunger switch 52 via an operating cable 54.

[0018] In the rear wheel suspension 30, the cushion rod 35 is extended and retracted by hydraulic pressure, and the swing arm 31 is displaced in response to the extension and contraction of the cushion rod 35, thereby adjusting the vehicle height of the saddle-riding type vehicle 1. In this manner, a vehicle height adjustment device 50 including the cushion rod 35, accumulator 51, plunger switch 52, connecting hose 53, and operating cable 54 is provided below the rear wheel suspension 30. In this case, the accumulator 51, which is a heavy component, is positioned below the body frame 10, thereby lowering the center of gravity of the saddle-riding type vehicle 1. The detailed configuration of the vehicle height adjustment device 50 will be described later.

[0019] 2 and 3, a muffler pipe 90 extends rearward from the front of the engine 15, passing beside the accumulator 51 (to the right in this embodiment). In front of the accumulator 51, the muffler pipe 90 branches into four left and right branch pipes 91a-91d. Beside the accumulator 51, the two left branch pipes 91a and 91b are combined into a lower pipe 92e, and the two right branch pipes 91c and 91d are combined into an upper pipe 92f. Behind the accumulator 51, the lower pipe 92e and the upper pipe 92f are combined into a single collecting pipe 93, which is connected to a muffler (not shown) near the rear wheel 25.

[0020] Below the body frame 10, the lower pipe 92e and upper pipe 92f of the muffler pipe 90 are shifted to the right (one side in the left-right direction), and the vehicle height control device 50 is shifted to the left (the other side in the left-right direction). The front and right sides of the vehicle height control device 50 are covered by an accumulator bracket 82, which also separates the vehicle height control device 50 from the muffler pipe 90. Even if the vehicle height control device 50 is installed next to the muffler pipe 90, the various components of the vehicle height control device 50 are protected from the heat of the muffler pipe 90. The detailed configuration of the accumulator bracket 82 will be described later.

[0021] As shown in Figure 4, shock absorber 41 of rear cushion 33 is divided into an upper cylinder 42 and a lower piston rod 43 (piston not shown). Cylinder 42 of shock absorber 41 is supported by engine 15, and piston rod 43 of shock absorber 41 is connected to cushion lever 34. Cylinder 42 and piston rod 43 of shock absorber 41 are elastically connected by coil spring 44. Rear cushion 33 absorbs impacts from the road surface by coil spring 44, and shock absorber 41 attenuates the amplitude of the coil spring 44.

[0022] The rear cushion 33 fits into the opening on the front side of the swing arm 31, and the rear cushion 33 is brought close to the swing shaft 32 of the swing arm 31. A cushion lever 34 is positioned below the swing shaft 32, and the cushion lever 34 connects the pivot frame 13, the rear cushion 33, and the swing arm 31. The lower part of the cushion lever 34 is formed into a U-shape in cross section (see Figure 8), and a cushion rod 35 is housed in the lower part of this U-shape. The cushion lever 34 and the cushion rod 35 form a link mechanism that connects the swing arm 31 and the rear cushion 33.

[0023] 4 and 5(A), the cushion rod 35 of the vehicle height adjusting device 50 has a cylindrical cylinder 61 and a rod main body 62 protruding from the cylinder 61. A lever-side connecting portion 63 is formed in the cylinder 61, and the cylinder 61 is connected to the cushion lever 34 via the lever-side connecting portion 63. A piston 64 that slides in the cylinder 61 is formed at the front end of the rod main body 62, and the piston 64 divides the interior of the cylinder 61 into an air chamber 65 and an oil chamber 66. An arm-side connecting portion 67 is provided at the rear end of the rod main body 62, and the rod main body 62 is connected to the swing arm 31 via the arm-side connecting portion 67.

[0024] The oil chamber 66 of the cylinder 61 of the cushion rod 35 is connected to a high-pressure oil chamber 72 of the accumulator 51 through a connecting hose 53 and a plunger switch 52. The accumulator 51 is formed in a cylindrical shape, and the inside of the accumulator 51 is divided by a piston 71 into a high-pressure oil chamber 72 and a high-pressure gas chamber 73. The plunger switch 52 is provided with a control valve 75 that controls the movement of oil between the accumulator 51 and the cushion rod 35. An operating cable 54 is connected to the control valve 75, and operating the operating cable 54 allows the movement of oil from the cushion rod 35 to the accumulator 51.

[0025] The movement of oil between the cushion rod 35 and the accumulator 51 changes the length of the cushion rod 35. When oil moves from the cushion rod 35 to the accumulator 51, the oil chamber 66 of the cushion rod 35 narrows and the cushion rod 35 becomes longer. When oil moves from the accumulator 51 to the cushion rod 35, the oil chamber 66 of the cushion rod 35 widens and the cushion rod 35 becomes shorter. When the cushion rod 35 becomes longer, the swing arm 31 moves upward and the vehicle height at the rear of the vehicle lowers, and when the cushion rod 35 shortens, the swing arm 31 moves downward and the vehicle height at the rear of the vehicle returns to its original position.

[0026] More specifically, as shown in Figure 5(A), an upward force acts on the swing arm 31 due to the reaction force of the weight of the vehicle and occupant. At this time, a tensile force acts on the cushion rod 35, and the oil in the cylinder 61 is compressed by the piston 64 of the cushion rod 35. When the occupant operates the operating cable 54, the control valve 75 of the plunger switch 52 connected to the operating cable 54 is opened. Oil is pushed out of the cylinder 61 of the cushion rod 35 and moves through the connecting hose 53 to the high-pressure oil chamber 72 of the accumulator 51.

[0027] The piston 64 of the cushion rod 35 moves in a direction narrowing the oil chamber 66, and the rod body 62 integral with the piston 64 protrudes from the cylinder 61, lengthening the cushion rod 35. As the cushion rod 35 becomes longer, the swing arm 31 is tilted upward from its initial state. This lowers the vehicle height at the rear of the vehicle, enabling stable acceleration with a low center of gravity. In particular, lowering the vehicle height when starting or exiting a corner raises the wheelie limit and improves acceleration. Furthermore, no energy from the engine 15 or the like is used when lowering the vehicle height.

[0028] As shown in Figure 5(B), when the operating cable 54 is not operated, the control valve 75 of the plunger switch 52 is closed and switched to a one-way valve. The one-way valve restricts the movement of oil from the cushion rod 35 to the accumulator 51, so the cushion rod 35 does not become longer. However, because the one-way valve allows oil to move from the accumulator 51 to the cushion rod 35, the cushion rod 35 is not restricted from becoming shorter. In this way, by closing the control valve 75 of the plunger switch 52, only the contraction of the cushion rod 35 is permitted.

[0029] When the load shifts to the front of the vehicle during braking and the load at the rear of the vehicle decreases, a downward force acts on the swing arm 31 due to the weight of the swing arm 31 and rear wheel 25 and the repulsive force of the rear cushion 33. At this time, a compressive force acts on the cushion rod 35, and the piston 64 of the cushion rod 35 expands the oil chamber 66 of the cylinder 61. Although the control valve 75 is closed, the movement of oil toward the cushion rod 35 is permitted via the one-way valve. Oil is drawn into the cylinder 61 of the cushion rod 35 and moves from the high-pressure oil chamber 72 of the accumulator 51 via the connecting hose 53.

[0030] The piston 64 of the cushion rod 35 moves in a direction that widens the oil chamber 66, and the rod body 62 integrated with the piston 64 enters the cylinder 61, shortening the cushion rod 35. As the cushion rod 35 shortens, the swing arm 31 is tilted downward and returned to its initial state, raising the rear of the vehicle to its original height. Even with a slight change in the vehicle body load that occurs when traveling in a straight line, oil moves little by little from the accumulator 51 to the cushion rod 35, gradually returning the vehicle height to its original level. Furthermore, no energy from the engine 15 or the like is used when returning the vehicle height.

[0031] The layout of the accumulator and the accumulator bracket will be described with reference to Figures 6 to 8. Figure 6 is a side view of the vicinity of the vehicle height control device of this embodiment. Figure 7 is a cross-sectional view of the vehicle height control device of Figure 6 taken along line BB. Figure 8 is a cross-sectional view of the vehicle height control device of Figure 6 taken along line CC. For ease of explanation, the swing arm is shown by a two-dot chain line in Figure 8.

[0032] As shown in Figure 6, the accumulator 51 is positioned lower than the pivot frame (body frame) 13 in the vehicle up-down direction, maintaining a low center of gravity of the vehicle. In the vehicle longitudinal direction, the accumulator 51 is closer to the swing shaft 32 of the swing arm 31 than the lower end of the rear cushion 33 (see Figure 4), so that the center of gravity of the vehicle is closer to the center in the vehicle longitudinal direction. At this time, by bringing the accumulator 51 closer to the swing center of the swing arm 31, the accumulator 51 is removed from the swing range of the swing arm 31, and interference between the swing arm 31 and the accumulator 51 is suppressed.

[0033] 6 and 7, the accumulator 51 is positioned to the side of the cushion lever 34 and the cushion rod 35, and overlaps the cushion lever 34 and the cushion rod 35 in a side view of the vehicle. This allows the components of the vehicle height adjustment device 50 to be concentrated together, and the connecting hose 53 connecting the accumulator 51 and the cushion rod 35 is shortened, improving maintainability. Furthermore, in a side view of the vehicle, the accumulator 51 is located directly below the pivot frame 13, and overlaps the muffler piping 90 that passes below the pivot frame 13. Arranging the accumulator 51 next to the muffler piping 90 lowers the center of gravity.

[0034] Furthermore, the muffler piping 90 bends in front of the accumulator 51 and extends rearward to the right of the vehicle center line L, with the accumulator 51 being positioned to the left of the vehicle center line L. More specifically, the cushion lever 34 and the cushion rod 35 are offset by 10 mm to one side (left side) of the vehicle center line L, which extends in the front-to-rear direction of the vehicle, and the accumulator 51 is further disposed to the left of the cushion lever 34 and the cushion rod 35. By positioning the muffler piping 90 to the right of the vehicle center line L, a space for arranging the accumulator 51 is secured to the left of the vehicle center line L.

[0035] 7 and 8, the vehicle height adjustment device 50 and the muffler piping 90 are separated by an accumulator bracket 82. The accumulator bracket 82 is fixed to the crankcase 16 of the engine 15 (see FIG. 6) via a suspension bracket 81. The accumulator bracket 82 is formed into a generally L-shaped plate shape in top view by a front wall portion 83 that covers the vehicle height adjustment device 50 from the front and a side wall portion 84 that covers the vehicle height adjustment device 50 from the right side (one side). The accumulator bracket 82 is preferably made of an aluminum alloy with high heat reflectivity or stainless steel with low thermal conductivity.

[0036] A C-shaped cylindrical accumulator holder 85 that holds the accumulator 51 is fixed to the left end of the rear surface of the front wall portion 83 of the accumulator bracket 82. A flange 86 is formed at the front end of the accumulator holder 85, and this flange 86 is screwed to the front wall portion 83 of the accumulator bracket 82, so that the accumulator holder 85 is cantilevered on the front wall portion 83. The accumulator 51 is inserted inside a cylindrical portion 87 of the accumulator holder 85, and a fastening band 88 is tightened from the outside of the cylindrical portion 87, so that the accumulator 51 is held in the accumulator holder 85.

[0037] In front of the vehicle height adjustment device 50, the muffler piping 90 bends to the right, and a bent portion 94 of the muffler piping 90 is positioned in front of the front wall portion 83 of the accumulator bracket 82. The front wall portion 83 of the accumulator bracket 82 extends like a plate in all directions, and the front wall portion 83 separates the accumulator 51, cushion lever 34, cushion rod 35, and other components from the bent portion 94 of the muffler piping 90. The front wall portion 83 of the accumulator bracket 82 blocks the wind while the vehicle is running, protecting the accumulator 51, cushion lever 34, cushion rod 35, and other components from the hot air that flows rearward from the bent portion 94 of the muffler piping 90 along with the wind while the vehicle is running.

[0038] On the right side of the vehicle height control device 50, a downstream portion 95 (lower piping 92e, upper piping 92f) of the muffler piping 90 extends rearward from the bent portion 94, and the downstream portion 95 of the muffler piping 90 is positioned to the right of the side wall portion 84 of the accumulator bracket 82. The side wall portion 84 of the accumulator bracket 82 extends like a plate in the vertical and front-to-rear directions, and the side wall portion 84 separates the accumulator 51, cushion lever 34, cushion rod 35, and other components from the downstream portion 95 of the muffler piping 90. The side wall portion 84 of the accumulator bracket 82 blocks hot air from the downstream portion 95 of the muffler piping 90, protecting the accumulator 51, cushion lever 34, cushion rod 35, and other components.

[0039] In this way, by bending the muffler piping 90 to the right in front of the cushion lever 34, a space for arranging the accumulator 51 is secured to the left of the cushion lever 34. The muffler piping 90 and the accumulator 51 are arranged side by side on either side of the cushion lever 34, thereby lowering the center of gravity of the vehicle. In addition, the accumulator 51 is covered from the front and right side by the accumulator bracket 82, so that the accumulator 51 is protected from the heat of the muffler piping 90. Therefore, the effect of heat from the muffler piping 90 is suppressed while the center of gravity of the vehicle is lowered.

[0040] As described above, according to this embodiment, vehicle height is adjusted by the extension and contraction of the cushion rod 35 by the working fluid in the accumulator 51. Lowering the vehicle height at the rear when starting or coming out of a corner allows for stable acceleration with a low center of gravity. In addition, by disposing the accumulator bracket 82 between the accumulator 51 and the muffler piping 90, the accumulator bracket 82 protects the accumulator 51 from the hot air in the muffler piping 90.

[0041] In this embodiment, the accumulator is positioned below the pivot frame, but it is sufficient that the accumulator is positioned below the swing axis of the swing arm. Even if an accumulator is added, the center of gravity of the vehicle can be maintained low as long as the accumulator is positioned below the swing axis of the swing arm.

[0042] In addition, although the cushion rod is extended and retracted by oil in this embodiment, the cushion rod may be extended and retracted by a working fluid other than oil. Note that the working fluid is not limited to a liquid, and gas may also be used.

[0043] Furthermore, in this embodiment, the accumulator bracket is fixed to the engine, but the accumulator bracket may be fixed to the vehicle body frame.

[0044] Furthermore, in this embodiment, the upper end of the rear cushion is supported by the engine and the body frame, but it is sufficient that the upper end of the rear cushion is supported by either the engine or the body frame.

[0045] Furthermore, in this embodiment, the cushion lever is supported by the body frame, but the cushion rod may be supported by the engine.

[0046] Furthermore, in this embodiment, the accumulator overlaps the cushion lever and the cushion rod in a side view of the vehicle, but it is sufficient that the accumulator overlaps the cushion lever or the cushion rod.

[0047] Furthermore, in this embodiment, the downstream portion of the muffler piping is located to the right of the vehicle center line and the accumulator is located to the left of the vehicle center line, but the downstream portion of the muffler piping may be located to the left of the vehicle center line and the accumulator may be located to the right of the vehicle center line.

[0048] In addition, in this embodiment, the accumulator, cushion lever, cushion rod and muffler piping are separated by the accumulator bracket, but it is sufficient that at least the accumulator and muffler piping are separated.

[0049] Furthermore, the term "saddle-type vehicle" is not limited to all vehicles in which the rider sits astride a seat, but also includes small scooter-type vehicles in which the rider does not sit astride a seat.

[0050] As described above, the rear wheel suspension (30) of this embodiment includes a swing arm (31) swingably supported on the body frame (10), and a rear wheel (25) rotatably supported on the swing arm. The rear wheel suspension (30) includes a rear cushion (33) that expands and contracts with the swing arm's swing, a cushion lever (34) connected to the lower end of the rear cushion, a cushion rod (35) connecting the cushion lever and the swing arm, an accumulator (51) that stores working fluid for expanding and contracting the cushion rod, and an accumulator bracket (82) that supports the accumulator. The vehicle height is adjusted by displacement of the swing arm caused by the expansion and contraction of the cushion rod. The muffler piping (90) extends rearward from the engine (15) and passes beside the accumulator, and the accumulator bracket separates the accumulator from the muffler piping. With this configuration, the vehicle height is adjusted by the expansion and contraction of the cushion rod by the working fluid in the accumulator. Lowering the rear of the vehicle when starting or coming out of a corner allows for stable acceleration with a low center of gravity. In addition, by placing an accumulator bracket between the accumulator and the muffler piping, the accumulator bracket protects the accumulator from the hot air in the muffler piping.

[0051] In the rear wheel suspension device for a saddle-ride type vehicle of this embodiment, the accumulator bracket separates the muffler piping from the cushion rod. With this configuration, the accumulator bracket is disposed between the muffler piping and the cushion rod, and the cushion rod is protected from the hot air in the muffler piping by the accumulator bracket.

[0052] In the rear wheel suspension device for a saddle-ride type vehicle of this embodiment, the accumulator bracket separates the muffler piping from the cushion lever. With this configuration, the accumulator bracket is disposed between the muffler piping and the cushion lever, and the accumulator bracket protects the cushion lever from the hot air in the muffler piping.

[0053] In the rear wheel suspension device for a saddle-ride type vehicle of this embodiment, the accumulator bracket has a front wall portion (83) that covers the accumulator from the front. With this configuration, the front wall portion of the accumulator bracket blocks the wind caused by running, protecting the accumulator from hot air that flows rearward from the muffler piping along with the wind caused by running.

[0054] In the rear wheel suspension of a saddle-ride type vehicle according to this embodiment, the muffler piping bends in front of the accumulator and extends rearward, passing on one side of a vehicle center line (L) extending in the fore-and-aft direction of the vehicle. The accumulator is positioned on the other side of the vehicle center line in the left-right direction. The accumulator bracket has a side wall (84) that covers the accumulator from the side. This side wall separates the accumulator from the downstream side of the bent portion (94) of the muffler piping. With this configuration, the downstream side of the bent portion of the muffler piping is positioned to one side of the vehicle center line in the left-right direction, thereby ensuring space for accumulator placement on the other side of the vehicle center line in the left-right direction. Furthermore, the side wall of the accumulator bracket protects the accumulator from hot air downstream of the muffler piping.

[0055] In the rear wheel suspension of a saddle-ride type vehicle of this embodiment, the front wall of the accumulator bracket separates the accumulator from the bent portion of the muffler piping. With this configuration, the front wall of the accumulator bracket blocks the wind from traveling, protecting the accumulator from hot air that flows rearward with the wind from the bent portion of the muffler piping.

[0056] Although the present embodiment has been described, other embodiments may be made by combining the above-described embodiments and modifications in whole or in part.

[0057] Furthermore, the technology of the present invention is not limited to the above-described embodiments, and various changes, substitutions, and modifications may be made without departing from the spirit of the technical idea. Furthermore, if the technical idea can be realized in a different way due to technological advances or other derived technologies, it may be implemented using that method. Therefore, the claims cover all embodiments that may fall within the scope of the technical idea. [Explanation of symbols]

[0058] 1: Saddle-type vehicle 10: Body frame 15: Engine 25: Rear wheel 30: Rear wheel suspension system 31: Swing arm 33: Rear cushion 34: Cushion lever 35: Cushion rod 51: Accumulator 82: Accumulator bracket 83: Front wall 84: Side wall 90: Muffler piping 94: Bend L: Vehicle center line

Claims

1. A rear wheel suspension device comprising a swing arm supported swingably on a vehicle body frame, and a rear wheel rotatably supported on the swing arm, a rear cushion that expands and contracts in accordance with the swing of the swing arm; a cushion lever connected to a lower end of the rear cushion; a cushion rod connecting the cushion lever and the swing arm; an accumulator that stores a working fluid that extends and contracts the cushion rod; an accumulator bracket that supports the accumulator, The vehicle height is adjusted by the displacement of the swing arm due to the extension and contraction of the cushion rod, a muffler pipe extending rearward from the engine and passing beside the accumulator; A rear wheel suspension device, wherein the accumulator bracket separates the accumulator from the muffler piping.

2. 2. The rear wheel suspension system according to claim 1, wherein the accumulator bracket separates the muffler piping from the cushion rod.

3. 3. The rear wheel suspension system according to claim 2, wherein the accumulator bracket separates the muffler piping from the cushion lever.

4. 4. The rear wheel suspension system according to claim 1, wherein the accumulator bracket has a front wall portion that covers the accumulator from the front.

5. the muffler pipe is bent in front of the accumulator and extends rearward, passing along one side in the left-right direction of a vehicle center line that extends in the front-rear direction of the vehicle, the accumulator is positioned on the other side in the left-right direction relative to the vehicle center line, 5. The rear wheel suspension device according to claim 4, wherein the accumulator bracket has a side wall portion that covers the accumulator from the side, and the side wall portion separates the accumulator from the downstream side of the bent portion of the muffler piping.

6. 6. The rear wheel suspension system according to claim 5, wherein a front wall portion of the accumulator bracket separates the bent portion of the muffler piping from the accumulator.

Images