Saddle-riding type vehicle

Abstract

This saddle-riding type vehicle has: an air cleaner (40) that purifies air supplied to an engine (31); an electric supercharger (50) that compresses the air supplied from the air cleaner (40); and a surge tank (60) that stores the air supplied from the electric supercharger (50) and the air supplied from the air cleaner (40) and supplies the air to the engine (31). The surge tank (60) is disposed rearward of a cylinder block (32) of the engine (31). The electric supercharger (50) is disposed frontward of the surge tank (60). The air cleaner (40) is disposed rearward or to the side of the electric supercharger (50).

Description

Straddle-type vehicle

[0001] The present invention relates to a straddle-type vehicle. This application claims priority based on Japanese Patent Application No. 2024-206089 filed on November 27, 2024, and incorporates its content herein by reference.

[0002] As superchargers used for the engine (internal combustion engine) of a vehicle, a turbocharger that utilizes the exhaust energy of the engine and a supercharger that utilizes a part of the driving force of the engine are known. In recent years, an electric supercharger that uses an electric motor to drive the supercharger is known.

[0003] International Publication No. 11 / 077898, German Patent Application Publication No. 102018200437

[0004] When a plurality of intake system components including a supercharger are arranged apart from each other, the pressure loss of the intake system increases. The problem to be solved by the present invention is to provide a straddle-type vehicle in which the pressure loss of the intake system is suppressed.

[0005] As a means for solving the above problems, the straddle-type vehicle according to this invention adopts the following configuration. (1) The straddle-type vehicle according to one aspect of the present invention includes an air cleaner (40) that purifies air supplied to an internal combustion engine (31, 131), an electric supercharger (50) that compresses the air supplied from the air cleaner (40), and a surge tank (60) that stores the air supplied from the electric supercharger (50) and the air supplied from the air cleaner (40) and supplies it to the internal combustion engine (31). The surge tank (60) is arranged behind the cylinder block of the internal combustion engine (31, 131), the electric supercharger (50) is arranged in front of the surge tank (60), and the air cleaner (40) is arranged behind or on the side of the electric supercharger (50). According to the aspect of (1), by adopting an electric supercharger, the degree of freedom in the layout of intake system components is increased. Therefore, the surge tank, the electric supercharger, and the air cleaner can be arranged close to each other. As a result, the pressure loss of the intake system is suppressed.

[0006] (2) In the embodiment of (1) above, the vehicle may also have a main frame (21) supporting the fuel tank (11), a down frame (24) supporting the internal combustion engine (31), and a seat frame (28) supporting the seat (18). In a side view, when the area enclosed by the main frame (21) and the down frame (24) is defined as the first area (R1), at least a part of the surge tank (60) and at least a part of the electric supercharger (50) may overlap the first area (R1) in a side view. According to the embodiment of (2), the surge tank, electric supercharger, and air cleaner are compactly arranged in the vertical and longitudinal directions of the saddle-type vehicle.

[0007] (3) In the embodiment of (1) or (2) above, there may be a pair of main frames (21) that are spaced apart to the left and right and support the fuel tank (11), and in a plan view, when the region between the pair of main frames (21) is defined as a third region (R3), in a plan view, at least a part of the surge tank (60), at least a part of the electric supercharger (50), and at least a part of the air cleaner (40) may overlap the third region (R3). According to embodiment of (3), the surge tank, electric supercharger, and air cleaner are compactly arranged in the center of the saddle-type vehicle in the left-right direction.

[0008] According to the present invention, it is possible to provide a saddle-type vehicle in which pressure loss in the intake system is suppressed.

[0009] This is a left side view of a motorcycle in the first embodiment. This is an explanatory diagram showing an overview of the intake system of the motorcycle. This is a plan view of the area around the power unit in the first embodiment. This is a left side view of the area around the power unit in the first embodiment. This is a plan view of the area around the power unit in the second embodiment. This is a left side view of the area around the power unit in the second embodiment. This is a plan view of the area around the power unit in the third embodiment. This is a left side view of the area around the power unit in the third embodiment.

[0010] Embodiments of the present invention will be described below with reference to the drawings. Unless otherwise specified, directions such as up, down, front, back, left, and right in the following description are the same as the directions of the vehicle described below. The drawings show an arrow FR indicating the front of the vehicle, an arrow LH indicating the left side of the vehicle, an arrow UP indicating the top of the vehicle, and a line CL indicating the left-right center of the vehicle body. The side approaching the left-right center of the vehicle may be called the inside in the left-right direction, and the side moving away from the left-right center of the vehicle may be called the outside in the left-right direction. The term "intermediate" used in the embodiments includes not only the center between the two ends of the object, but also the inside range between the two ends of the object. In the following description, it is assumed that the body of the saddle-type vehicle is stationary in an upright state with no tilt to the left or right and a steering angle of 0 degrees, and furthermore, it is in an unloaded state of 1G on a horizontal plane.

[0011] (First Embodiment) Figure 1 is a left side view of a motorcycle 1 in the first embodiment. The motorcycle 1 has a front wheel 2 which is a steering wheel, a rear wheel 8 which is a drive wheel, a power unit 30, a fuel tank 11, and a seat 18. The front wheel 2 is rotatably supported at the lower ends of a pair of left and right front forks 3. The upper parts of the pair of left and right front forks 3 are connected by a pair of upper and lower bridges 4. A head pipe 5 is positioned between the pair of left and right front forks 3 and the pair of upper and lower bridges 4. The head pipe 5 extends from top to bottom. The head pipe 5 is slightly tilted forward from top to bottom. The pair of upper and lower bridges 4 are rotatable relative to the head pipe 5. A handle 6 is connected to the upper bridge 4. The front wheel 2 is steerable by the handle 6.

[0012] Figure 3 is a plan view of the area around the power unit 30 in the first embodiment. Figure 4 is a left side view of the area around the power unit 30 in the first embodiment. In the following left side views, the outlines of the fuel tank 11 and seat 18 of the motorcycle 1 are shown by dashed lines. The motorcycle 1 has a frame 20 that extends to the rear from the head pipe 5, splitting to the left and right. The frame 20 is a so-called cradle frame that encloses and supports the entire power unit 30. The frame 20 is formed by connecting a plurality of pipes, etc., by welding or the like. The frame 20 has a pair of left and right main frames 21, a pair of left and right first connecting pipes 22, a pair of left and right down frames 24, a pair of left and right second connecting pipes 23, and a pair of left and right seat frames 28.

[0013] As shown in Figures 3 and 4, the main frame 21 has a front main pipe 21f, a rear main pipe 21r, and a cross main pipe 21c. The front end of the front main pipe 21f is connected to the upper part of the head pipe 5. As shown in Figure 4, the front main pipe 21f extends from front to rear. The front main pipe 21f is slightly inclined downward from front to rear. As shown in Figure 3, the front main pipe 21f is slightly inclined outward in the left-right direction from front to rear. The inclination angle of the front half of the front main pipe 21f is greater than the inclination angle of the rear half. As shown in Figure 4, a bend is located between the rear end of the front main pipe 21f and the upper end of the rear main pipe 21r.

[0014] The rear main pipe 21r extends from top to bottom. The rear main pipe 21r slopes slightly towards the rear from top to bottom. The cross main pipe 21c extends along the left-right direction. Both ends of the cross main pipe 21c are connected to the tops of the left and right pair of rear main pipes 21r.

[0015] The fuel tank 11 of the motorcycle 1 (see Figure 1) is positioned above the front main pipe 21f of the main frame 21. The fuel tank 11 is supported by the main frame 21.

[0016] The front end of the first connecting pipe 22 is connected to the lower part of the head pipe 5. The rear end of the first connecting pipe 22 is connected to the middle part of the front main pipe 21f.

[0017] As shown in Figures 3 and 4, the down frame 24 has a front down pipe 24f, an intermediate down pipe 24m, and a rear down pipe 24r. The front end of the front down pipe 24f is connected to the lower part of the first connecting pipe 22. As shown in Figure 4, the front down pipe 24f extends from top to bottom. The front down pipe 24f is slightly inclined towards the rear from top to bottom. As shown in Figure 3, the lower part of the front down pipe 24f is inclined outward in the left-right direction. As shown in Figure 4, a bend is positioned between the lower end of the front down pipe 24f and the front end of the intermediate down pipe 24m.

[0018] The intermediate downpipe 24m extends along the front-rear direction. A bend is positioned between the rear end of the intermediate downpipe 24m and the lower end of the rear downpipe 24r. The rear downpipe 24r extends from bottom to top. The rear downpipe 24r slopes backward from bottom to top.

[0019] The power unit 30 of the motorcycle 1 is positioned between the main frame 21 and the down frame 24. The power unit 30 is supported by the down frame 24.

[0020] The lower end of the second connecting pipe 23 is connected to the middle section of the front down pipe 24f. The upper end of the second connecting pipe 23 is connected to the middle section of the first connecting pipe 22.

[0021] The lower end of the rear main pipe 21r of the aforementioned main frame 21 is connected to the middle section of the rear down pipe 24r of the down frame 24. A pivot gusset 25 is formed at the connection point between the two.

[0022] As shown in Figure 1, the rear wheel 8 of the motorcycle 1 is rotatably supported at the rear ends of a pair of left and right swing arms 9. The swing arms 9 extend along the front-rear direction. The front ends of the swing arms 9 are rotatably supported at a pivot gusset 25. The rear wheel 8 is swingable up and down by the swing arms 9.

[0023] As shown in Figures 3 and 4, the seat frame 28 has a front seat pipe 28f and a rear seat pipe 28r. The front end of the front seat pipe 28f is connected to the middle section of the cross main pipe 21c of the main frame 21. As shown in Figure 4, the front seat pipe 28f extends from front to rear. As shown in Figure 3, the front seat pipe 28f is inclined outward in the left-right direction from front to rear. The inclination angle of the front half of the front seat pipe 28f is smaller than that of the rear half. As shown in Figure 4, a bend is located between the rear end of the front seat pipe 28f and the front end of the rear seat pipe 28r. The rear seat pipe 28r extends from front to rear. The rear seat pipe 28r is inclined slightly upward from front to rear.

[0024] The seat 18 of the motorcycle 1 (see Figure 1) is positioned above the seat frame 28. The seat 18 is supported by the seat frame 28.

[0025] The upper end of the rear down pipe 24r of the down frame 24, as described above, is connected to the front part of the rear seat pipe 28r of the seat frame 28. A rear suspension gusset 29 is formed at the connection point between the two. As shown in Figure 1, the rear suspension 19 is installed between the rear suspension gusset 29 and the rear end of the swing arm 9.

[0026] In the side view of the motorcycle 1 shown in Figure 4, the first region R1 and the second region R2 are defined as follows. The first region R1 is the area enclosed by the front main pipe 21f and rear main pipe 21r of the main frame 21, the front down pipe 24f, intermediate down pipe 24m and rear down pipe 24r of the down frame 24, and the first connecting pipe 22 and the second connecting pipe 23. The second region R2 is the area enclosed by the rear main pipe 21r of the main frame 21, the rear down pipe 24r of the down frame 24, and the front seat pipe 28f of the seat frame 28. The second region R2 is roughly in the shape of an inverted triangle.

[0027] In the plan view of the motorcycle 1 shown in Figure 3, a pair of main frames 21 are arranged spaced apart in the left-right direction. In the plan view, the region between the pair of main frames 21 is defined as the third region R3.

[0028] As shown in Figure 4, the power unit 30 of the motorcycle 1 is located in the first region R1 in a side view. The power unit 30 consists of an engine (internal combustion engine) 31, a crankcase 33, and a transmission 38 arranged in an L-shape. The engine 31 is a multi-cylinder in-line engine with multiple cylinders arranged in the left-right direction. The engine 31 has a cylinder block 32 that houses the multiple cylinders. The cylinder block 32 rises upward from the crankcase 33 along the front downpipe 24f. The transmission 38 is located behind the crankcase 33. The driving force output from the transmission 38 rotates the rear wheel 8 (see Figure 1).

[0029] Figure 2 is an explanatory diagram showing an overview of the intake system components of motorcycle 1. Motorcycle 1 has an air cleaner 40, an electric supercharger 50, a surge tank 60, and a throttle body 35 as intake system components for the engine 31. The air cleaner 40 is connected to the electric supercharger 50 via a first pipe 45. The electric supercharger 50 is connected to the surge tank 60 via a supercharger pipe 55. The surge tank 60 is connected to the intake port of the engine 31 via a throttle body 35. The air cleaner 40 is connected to the surge tank 60 via a second pipe 47. Intake air that does not go through the electric supercharger 50 can be supplied to the surge tank 60 via the second pipe 47.

[0030] The air cleaner 40 purifies the air supplied to the engine 31. As shown in Figure 4, the air cleaner 40 has a case, an intake port, a first exhaust port, a second exhaust port, and an element 41. The case has a flattened shape. The intake port, the first exhaust port, and the second exhaust port are formed in the case. The element 41 divides the inside of the case into a dirty side 40d on the intake port side and a clean side 40c on the first and second exhaust port side. Outside air is taken in from the intake port to the dirty side 40d inside the case. The element 41 captures impurities contained in the air. The purified air passes through the element 41 and moves to the clean side 40c. The air is discharged from the first and second exhaust ports on the clean side 40c.

[0031] The electric supercharger 50 compresses the air supplied from the first exhaust port of the air cleaner 40. The electric supercharger 50 has a case 51, an intake port, an exhaust port, an impeller, and an electric motor 52 (see Figure 3). The case 51 is disc-shaped and houses the impeller inside. The intake port is located on one side of the case 51 in the direction of the central axis. The intake port opens in the direction of the central axis of the case 51. The exhaust port opens tangentially to the outer circumference of the case 51. The electric motor 52 is located on the other side of the case 51 in the direction of the central axis (see Figure 8). The electric motor 52 is cooled by air cooling or water cooling. The electric motor 52 rotates the impeller. Air supplied from the air cleaner 40 is taken into the central part of the case 51 from the intake port. The air is compressed from the central part to the outer circumference of the case 51 by the rotation of the impeller. The compressed air is discharged from the exhaust port.

[0032] The surge tank 60 stores air supplied from the electric supercharger 50 and the air cleaner 40, and supplies it to the engine 31. The surge tank 60 has a first intake port, a second intake port, and multiple exhaust ports. The first intake port takes in air supplied from the exhaust port of the electric supercharger 50. The second intake port takes in air supplied from the second exhaust port of the air cleaner 40. The multiple exhaust ports supply air to the multiple cylinders of the engine 31. Therefore, as shown in Figure 3, the length of the surge tank 60 in the left-right direction is equal to the length of the engine 31 in the left-right direction.

[0033] The throttle body 35 is positioned between the surge tank 60 and the engine 31. Multiple throttle bodies 35 are positioned corresponding to the multiple cylinders of the engine 31. The throttle body 35 adjusts the amount of air supplied to the engine 31 in accordance with the throttle opening of the motorcycle 1. An injector is positioned between the throttle body 35 and the engine 31. The injector injects fuel into the air supplied to the engine 31. A mixture of air and fuel is supplied to the engine 31.

[0034] The amount of air supplied to the engine 31 may fluctuate rapidly due to the operation of the accelerator of the motorcycle 1. Even in this case, the air stored in the surge tank 60 is supplied to the engine 31. This improves the responsiveness to rapid changes in the amount of intake air supplied to the engine 31.

[0035] The surge tank 60 is positioned behind the cylinder block 32 of the engine 31. Because the surge tank 60 is positioned in the space above the transmission 38, there is a high degree of flexibility in the layout of the surge tank 60. The surge tank 60 is positioned close to the cylinder block 32, with the throttle body 35 in between. This suppresses pressure loss of the air supplied from the surge tank 60 to the engine 31.

[0036] The surge tank 60 is formed in an inverted T shape when viewed from the front. The surge tank 60 has a first portion 60a that is long in the left-right direction and a second portion 60b that is long in the up-down direction. The first portion 60a is connected to the throttle body 35. The second portion 60b rises upward from the first portion 60a. The second portion 60b is formed in the left-right central part of the first portion 60a. The second portion 60b is positioned between a pair of left and right main frames 21. The upper end of the second portion 60b is positioned below the front main pipe 21f of the main frame 21.

[0037] The electric supercharger 50 is positioned in front of the surge tank 60. All or part of the electric supercharger 50 is positioned in front of the surge tank 60. The electric supercharger 50 is positioned above the engine 31. The central axis of the case 51 of the electric supercharger 50 is aligned in the left-right direction. The exhaust port of the electric supercharger 50 opens to the rear. The first intake port of the surge tank 60 is formed on the upper part of the second portion 60b and opens to the front. The exhaust port of the electric supercharger 50 and the first intake port of the surge tank 60 are connected by a supercharger piping 55.

[0038] The air cleaner 40 is located behind the electric supercharger 50. All or part of the air cleaner 40 is located behind the electric supercharger 50. The air cleaner 40 is located above the surge tank 60. The thickness direction of the air cleaner 40 is aligned with the vertical direction. The air cleaner 40 is located above the front main pipe 21f of the main frame 21. The air cleaner 40 may be located to the side (right or left) of the electric supercharger 50. At least part of the air cleaner 40 may be located to the side of the electric supercharger 50.

[0039] The dirty side 40d of the air cleaner 40 is positioned at the rear, and the clean side 40c is positioned at the front. Alternatively, the dirty side 40d may be positioned at the front and the clean side 40c at the rear. The first exhaust port of the air cleaner 40 opens forward. The intake port of the electric supercharger 50 opens to the right. The first exhaust port of the air cleaner 40 and the intake port of the electric supercharger 50 are connected by an L-shaped first pipe 45. The second exhaust port of the air cleaner 40 opens downward. The second intake port of the surge tank 60 opens upward. The second exhaust port of the air cleaner 40 and the second intake port of the surge tank 60 are connected by a second pipe 47. The second pipe 47 is formed in a straight line. The air cleaner 40 is positioned close to the surge tank 60, and the length of the second pipe 47 is shortened. As a result, pressure loss of the air supplied from the air cleaner 40 to the surge tank 60 is suppressed.

[0040] The motorcycle 1 of this embodiment employs an electric supercharger 50. This increases the freedom of layout for intake system components compared to cases where a mechanically driven turbocharger or supercharger is used. As a result, the surge tank 60, electric supercharger 50, and air cleaner 40 can be placed in close proximity. This suppresses pressure loss in the intake system. Consequently, improvements in energy efficiency and responsiveness can be expected.

[0041] In the first embodiment, the surge tank 60 is disposed behind the cylinder block 32 of the engine 31. The electric supercharger 50 is disposed in front of the surge tank 60. The air cleaner 40 is disposed behind the electric supercharger 50. Thereby, the surge tank 60, the electric supercharger 50, and the air cleaner 40 can be disposed in proximity to each other.

[0042] In the side view shown in FIG. 4, the entire surge tank 60 overlaps with the first region R1. The lower part of the electric supercharger 50 overlaps with the first region R1. Thereby, the surge tank 60 and the electric supercharger 50 are disposed compactly in the vertical and longitudinal directions of the motorcycle 1.

[0043] In the plan view shown in FIG. 3, the central portion in the left-right direction of the surge tank 60 overlaps with the third region R3. In particular, the second portion 60b of the surge tank 60 is included in the third region R3. Also, the entire electric supercharger 50 and the central portion in the left-right direction of the air cleaner 40 overlap with the third region R3. The first pipe 45 is disposed inside the pair of left and right seat frames 28. Thereby, the surge tank 60, the electric supercharger 50, and the air cleaner 40 are disposed compactly in the central portion in the left-right direction of the motorcycle 1. When the surge tank 60 is short in the left-right direction, it is desirable that the entire surge tank 60 is included in the third region R3. The first pipe 45 may be disposed so as to straddle the outside in the left-right direction of the seat frame 28.

[0044] (Second Embodiment) FIG. 5 is a plan view of the periphery of the power unit 130 in the second embodiment. FIG. 6 is a left side view of the periphery of the power unit 130 in the second embodiment. The frame 120 of the motorcycle 101 in the second embodiment is a so-called diamond frame that uses the power unit 130 as a part of the frame. The description of the second embodiment regarding the same points as those of the above-described embodiment may be omitted.

[0045] The motorcycle 1 has a frame 120 that extends rearward from the head pipe 105. The frame 120 includes a head block 110, a pair of left and right main frames 121, a pivot block 123, and a pair of left and right seat frames 128. The head block 110 includes the head pipe 105. In the plan view shown in Figure 5, the head block 110 is triangular in shape with the head pipe 105 as its front vertex.

[0046] In the plan view shown in Figure 5, the main frame 121 extends rearward from corresponding vertices of the two rear vertices of the head block 110. The main frame 121 inclines outward in the left-right direction from the front end to the middle section, and inward in the left-right direction from the middle section to the rear end. In the side view shown in Figure 6, the main frame 121 inclines downward from the front to the rear. The cross-sectional shape of the main frame 121 perpendicular to the extension direction is a vertically elongated rectangle, with a height greater in the vertical direction than in the left-right direction. The interior of the main frame 121 is hollow. The main frame 121 has an engine hanger 122 that extends downward. The front end of the cylinder block 132 or crankcase 133 of the power unit 130 is connected to the tip of the engine hanger 122.

[0047] The pivot block 123 is formed in an L-shape in the side view shown in Figure 6. The pivot block 123 has a pair of left and right front frames 123f, a pair of left and right rear frames 123r, and a pair of upper and lower cross members (not shown). The front frames 123f extend rearward from the rear end of the main frame 121. The front frames 123f are inclined downward from front to rear. A bent portion is positioned between the rear end of the front frames 123f and the upper end of the rear frames 123r.

[0048] The rear frame 123r extends along the vertical direction. The rear end portions of the transmission 138 of the power unit 30 are connected to the upper and lower end portions of the rear frame 123r. A pivot 125 is formed at an intermediate portion of the rear frame 123r. At the pivot 125, the front end portion of a swing arm (not shown) is rotatably supported. The cross member is disposed inside the pair of left and right rear frames 123r and connects the two. The cross member is disposed at the upper and lower end portions of the rear frame 123r.

[0049] The seat frame 128 includes an upper seat pipe 128u and a lower seat pipe 128d. The upper seat pipe 128u extends rearward from the rear end portion of the front frame 123f of the pivot block 123. The lower seat pipe 128d extends rearward from the upper end portion of the rear frame 123r of the pivot block 123. The upper seat pipe 128u and the lower seat pipe 128d are inclined upward from the front to the rear. The rear end portion of the lower seat pipe 128d is connected to the rear portion of the upper seat pipe 128u.

[0050] The power unit 130 has an engine (internal combustion engine) 131, a crankcase 133, and a transmission 138 arranged in an L shape. The engine 131 is an in-line multi-cylinder engine in which a plurality of cylinders are arranged in the left-right direction. The engine 131 has a cylinder block 132 that houses the plurality of cylinders. The cylinder block 132 rises upward from the crankcase 133. The cylinder block 132 is inclined forward from the bottom to the top. The transmission 138 is disposed behind the crankcase 133.

[0051] The motorcycle 101 has an air cleaner 40, an electric supercharger 50, and a surge tank 60 as intake system components for the engine 131.

[0052] The surge tank 60 is located behind the cylinder block 132 of the engine 131. In the side view shown in Figure 6, the front of the surge tank 60 overlaps with the main frame 121. As shown in the plan view in Figure 5, the width of the surge tank 60 in the left-right direction decreases from front to rear so that it fits inside the pair of main frames 121 and pivot block 123.

[0053] The electric supercharger 50 is positioned in front of the surge tank 60. The electric supercharger 50 is positioned above the engine 131. The exhaust port of the electric supercharger 50 opens to the rear. The first intake port of the surge tank 60 opens to the front. The exhaust port of the electric supercharger 50 and the first intake port of the surge tank 60 are connected by a supercharger piping 55.

[0054] The air cleaner 40 is positioned behind the electric supercharger 50. The air cleaner 40 is positioned above the surge tank 60. The dirty side 40d of the air cleaner 40 is positioned at the rear, and the clean side 40c is positioned at the front. Alternatively, the dirty side 40d may be positioned at the front and the clean side 40c at the rear. The first exhaust port of the air cleaner 40 opens forward. The intake port of the electric supercharger 50 opens to the right. The first exhaust port of the air cleaner 40 and the intake port of the electric supercharger 50 are connected by a first pipe 45. The second exhaust port of the air cleaner 40 opens downward. The second intake port of the surge tank 60 opens upward. The second exhaust port of the air cleaner 40 and the second intake port of the surge tank 60 are connected by a second pipe 47. The second pipe 47 is formed in a straight line. The air cleaner 40 is positioned closer to the surge tank 60, and the length of the second pipe 47 is shortened. As a result, pressure loss of the air supplied from the air cleaner 40 to the surge tank 60 is suppressed.

[0055] In the second embodiment, similar to the first embodiment, the surge tank 60 is positioned behind the cylinder block 32 of the engine 31, the electric supercharger 50 is positioned in front of the surge tank 60, and the air cleaner 40 is positioned behind the electric supercharger 50. This allows the surge tank 60, electric supercharger 50, and air cleaner 40 to be positioned in close proximity.

[0056] In the side view shown in Figure 6, the front of the surge tank 60 and most of the electric supercharger 50 overlap the main frame 121. As a result, the surge tank 60 and electric supercharger 50 are compactly arranged in the vertical and longitudinal directions of the motorcycle 101.

[0057] In the plan view shown in Figure 5, the surge tank 60, electric supercharger 50, and air cleaner 40 are positioned inside the left and right pair of main frames 121 and the left and right pair of front frames 123f of the pivot block 123. As a result, the surge tank 60, electric supercharger 50, and air cleaner 40 are compactly positioned in the center of the motorcycle 101 in the left-right direction.

[0058] (Third Embodiment) Figure 7 is a plan view of the area around the power unit 130 in the third embodiment. Figure 8 is a left side view of the area around the power unit 130 in the second embodiment. The description of the third embodiment regarding points that are the same as those of the second embodiment described above may be omitted.

[0059] The surge tank 60 is located behind the cylinder block 132 of the engine 131. The layout of the surge tank 60 is the same as in the second embodiment. The electric supercharger 50 is located in front of the surge tank 60. The layout of the electric supercharger 50 is the same as in the second embodiment.

[0060] The air cleaner 40 is located behind the electric supercharger 50. The air cleaner 40 is located below the surge tank 60. All or part of the air cleaner 40 is located below the electric supercharger 50. The dirty side 40d of the air cleaner 40 is located at the rear, and the clean side 40c is located at the front. The dirty side 40d may be located at the front, and the clean side 40c may be located at the rear. The first exhaust port of the air cleaner 40 opens to the right. The first exhaust port of the air cleaner 40 and the intake port of the electric supercharger 50 are connected by a U-shaped first pipe 45. The second exhaust port of the air cleaner 40 opens upward. The second intake port of the surge tank 60 opens downward. The second exhaust port of the air cleaner 40 and the second intake port of the surge tank 60 are connected by a second pipe 47. The second pipe 47 is formed in a straight line. The air cleaner 40 is positioned closer to the surge tank 60, and the length of the second pipe 47 is shortened. As a result, pressure loss of the air supplied from the air cleaner 40 to the surge tank 60 is suppressed.

[0061] In the third embodiment, similar to the embodiment described above, the surge tank 60 is positioned behind the cylinder block 32 of the engine 31, the electric supercharger 50 is positioned in front of the surge tank 60, and the air cleaner 40 is positioned behind the electric supercharger 50. This allows the surge tank 60, electric supercharger 50, and air cleaner 40 to be positioned in close proximity.

[0062] In the side view shown in Figure 8, the front of the surge tank 60 and most of the electric supercharger 50 overlap the main frame 121. As a result, the surge tank 60 and electric supercharger 50 are compactly arranged in the vertical and longitudinal directions of the motorcycle 101.

[0063] In the plan view shown in Figure 7, the surge tank 60, electric supercharger 50, and air cleaner 40 are positioned inside the left and right pair of main frames 121 and the left and right pair of front frames 123f of the pivot block 123. As a result, the surge tank 60, electric supercharger 50, and air cleaner 40 are compactly positioned in the center of the motorcycle 101 in the left-right direction.

[0064] The saddle-type vehicle of the embodiment may also be applied to saddle-type electric vehicles other than motorcycles. The saddle-type vehicle includes all vehicles on which the driver straddles the vehicle body, and includes not only motorcycles but also three-wheeled vehicles (including vehicles with one front wheel and two rear wheels, as well as vehicles with two front wheels and one rear wheel) or four-wheeled vehicles (such as four-wheeled buggies). Furthermore, the configuration in the above embodiment is just one example of the present invention, and various modifications are possible without departing from the spirit of the invention, such as replacing the components of the embodiment with well-known components.

[0065] R1...First area R2...Second area R3...Third area 1...Motorcycle (saddle-type vehicle) 11...Fuel tank 18...Seat 21...Main frame 24...Down frame 28...Seat frame 31...Engine (internal combustion engine) 32...Cylinder block 40...Air cleaner 50...Electric supercharger 60...Surge tank 131...Engine (internal combustion engine)

Claims

1. A saddle-type vehicle comprising: an air cleaner (40) for purifying the air supplied to an internal combustion engine (31, 131); an electric supercharger (50) for compressing the air supplied from the air cleaner (40); and a surge tank (60) for storing the air supplied from the electric supercharger (50) and the air supplied from the air cleaner (40) and supplying them to the internal combustion engine (31), wherein the surge tank (60) is located behind the cylinder block of the internal combustion engine (31, 131), the electric supercharger (50) is located in front of the surge tank (60), and the air cleaner (40) is located behind or to the side of the electric supercharger (50).

2. A saddle-type vehicle according to claim 1, comprising: a main frame (21) supporting a fuel tank (11); a down frame (24) supporting the internal combustion engine (31); and a seat frame (28) supporting a seat (18), wherein, in a side view, the region enclosed by the main frame (21) and the down frame (24) is defined as a first region (R1), and in a side view, at least a portion of the surge tank (60) and at least a portion of the electric supercharger (50) overlap the first region (R1).

3. A saddle-type vehicle according to claim 1 or 2, having a pair of main frames (21) spaced apart to the left and right and supporting a fuel tank (11), wherein, in a plan view, when the region between the pair of main frames (21) is defined as a third region (R3), at least a portion of the surge tank (60), at least a portion of the electric supercharger (50), and at least a portion of the air cleaner (40) overlap the third region (R3) in a plan view.

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