WO2005038971A1

WO2005038971A1 - Fuel cell system and vehicle using same

Info

Publication number: WO2005038971A1
Application number: PCT/JP2004/015410
Authority: WO
Inventors: Hideo Kohda
Original assignee: Yamaha Hatsudoki Kabushiki Kaisha
Priority date: 2003-10-20
Filing date: 2004-10-19
Publication date: 2005-04-28
Also published as: JPWO2005038971A1; TW200529489A; JP4585450B2

Abstract

Disclosed are a fuel cell system (100) wherein a fuel cell (102) can be efficiently cooled by a simple structure, and a vehicle using such a fuel cell system. The fuel cell system (100) includes the fuel cell (102) which is capable of producing electrical energy through electrochemical reaction between fuel and oxygen. A heat exchanger (118) is arranged near the fuel cell (102) for cooling a medium passing through in the fuel cell (102). An aqueous solution of methanol is used as the fuel and the medium. An air current is generated by a fan (130) for cooling the fuel cell (102) and the heat exchanger (118).

Description

Specification

Fuel cell system and vehicle using the same

Technical field

The present invention relates to a fuel cell system and a vehicle using the same, and more specifically, to a fuel cell system including a heat exchanger for cooling fuel supplied to a fuel cell, and to a fuel cell system using the same. For vehicles.

Background art

[0002] A fuel cell that generates electric power by an electrochemical reaction between fuel and oxygen generates heat by the electrochemical reaction. Therefore, a fuel cell system that cools the fuel to be supplied to the fuel cell in order to suppress the temperature rise of the fuel cell due to this heat generation is known (for example, see Patent Document 1).

Patent Document 1: Japanese Patent Application Laid-Open No. 2002-203587

Disclosure of the invention

Problems to be solved by the invention

[0003] However, in the conventional fuel cell system, even though the fuel to be supplied to the fuel cell is cooled, the temperature of the fuel cell rises excessively, damaging the electrolyte membrane and preventing efficient power generation. There is. In this case, it is necessary to further cool the fuel cell.

Here, if a device for cooling the fuel cell is provided separately, there is a problem that the configuration of the fuel cell system becomes complicated. This problem is particularly noticeable when the fuel cell system is to be mounted on a vehicle such as a motorcycle.

Therefore, a main object of the present invention is to provide a fuel cell system and a vehicle using the same, which can efficiently cool the fuel cell with a simple configuration. Means for solving the problem

[0005] According to one aspect of the present invention, a fuel cell capable of generating electric energy by an electrochemical reaction between fuel and oxygen, and a fuel cell provided near the fuel cell and cooling a medium passing through the fuel cell A fuel cell system is provided, comprising: a heat exchanger; and an airflow generating means for generating a flow of air for cooling the fuel cell and the heat exchanger. [0006] In the present invention, a heat exchanger is provided near the fuel cell. Then, an airflow around the fuel cell for cooling the fuel cell from the outside and an airflow for cooling the heat exchanger for cooling the medium passing through the fuel cell are generated by the airflow generation means, and the fuel flow is generated. Cool the battery. Therefore, the fuel cell can be efficiently cooled with a simple configuration.

[0007] Preferably, the fuel and the medium are aqueous methanol solutions, and the air flow generating means generates a flow of air in a direction toward the fuel cell or a direction toward the heat exchange fuel cell. Including fans to do.

As described above, since the methanol aqueous solution is directly used as the fuel, a fuel reformer is not required, and the configuration of the fuel cell system is simplified. In addition, since the aqueous methanol solution supplied to the fuel cell is used as a medium (refrigerant) for cooling the internal power of the fuel cell, there is no need to provide a separate device for cooling and circulating another refrigerant. It can be cooled with a simple configuration. Therefore, this fuel cell system can be suitably used for vehicles such as motorcycles in which the installation space for equipment is limited.

[0009] Further, a flow of air from the fuel cell to the heat exchanger is generated by the fan, for example. In other words, the fuel cell and the heat exchange ^ are arranged in the direction of air flow. Therefore, the air used for cooling the fuel cell is supplied to the heat exchange through the outer periphery of the fuel cell and can be used for cooling the aqueous methanol solution. In this way, the heat exchange with the outside of the fuel cell can be efficiently cooled in order by the one-way air flow.

[0010] According to another aspect of the present invention, the fuel cell system includes the above-described fuel cell system and a seat portion for a passenger to sit on, and the fuel cell and the heat exchanger ^ are arranged back and forth under the seat portion. In addition, a vehicle is provided in which the airflow generating means is provided between the fuel cell and the heat exchanger or behind the fuel cell and the heat exchanger.

[0011] In the present invention, among the devices constituting the fuel cell system, the relatively large fuel cell and the heat exchange ^^ are arranged under the seat having a relatively large space. The heat exchanger can be easily arranged. Further, since the heavy fuel cell is disposed near the center of the vehicle, the moment of inertia with respect to the center of gravity of the vehicle can be reduced. Furthermore, since the fuel cell, the heat exchanger and the airflow generating means are arranged substantially in series, And an air flow passing through the heat exchanger can be efficiently generated by the air flow generation means.

[0012] According to another aspect of the present invention, the above-described fuel cell system, a seat portion for a passenger to sit on, and a lower portion of the seat portion are formed to be wide in the left-right direction and at least in the up-down direction. A vehicle is provided that includes an elongated plate member. In this vehicle, a fuel cell is provided on the front side of the plate-like member, heat exchange is provided on the rear side of the plate-like member, and an air flow generating means is provided on the rear side of the heat exchange, and At a position sandwiched between the fuel cell and the heat exchange, a through-hole for passing the air flow generated by the air flow generation means is provided.

According to the present invention, since the fuel cell is provided on the front side of the plate-like portion and the intersection is provided on the rear side, the positioning between the fuel cell and the heat exchanger is facilitated. In addition, since the through holes are provided in the plate-shaped portion, air flows smoothly to the heat exchanger of the fuel cell, and the outside of the fuel cell and the medium passing through the heat exchanger can be efficiently cooled. .

Preferably, the heat exchange is cooled by the airflow used for cooling the fuel cell, and the airflow generated by the fan is directly applied to the external airflow. It is also configured so that the amount of air flow used for cooling the fuel cell, which is also cooled by the air flow, is greater than the amount of air flow flowing directly from the outside air to the heat exchanger. In this case, the fuel cell can be reliably cooled from the outside, and the medium can be efficiently cooled by heat exchange.

[0015] Preferably, a plate-shaped first central portion that extends obliquely rearward and upward and is wide in the left-right direction, and extends along both left and right end portions of the first central portion and has a width in the front-rear direction. There is provided a lya frame having a wide left and right plate-like portion, and a first central portion is a plate-like member. In this case, the Lya frame can secure appropriate rigidity according to the bending moment applied to the Lya frame, while having a lightweight and simple shape. In addition, it is possible to easily secure a space for installing auxiliary equipment of the vehicle at the front or rear side of the lary frame.

[0016] Preferably, a plate-shaped second central portion extending at least in the front-rear direction and being wide in the vertical direction, and extending along both upper and lower end portions of the second central portion and being wide in the left-right direction, respectively. A main frame having a plate-like upper portion and a lower portion formed is provided, and a rear end of the main frame is connected to the rear frame. In this case, the secondary moment of section of the main frame can be easily increased. In addition, it is easier to secure rigidity than before even though it has a light and simple shape.

[0017] Preferably, a main switch is provided at a second central portion of the main frame.

In this case, a member for separately attaching the main switch becomes unnecessary. This facilitates the handling of wires around the handle.

[0018] Further preferably, a head pipe formed at the front end of the main frame, a front fork rotatably engaged with the head pipe, and a rod attached to the main switch are provided, and the main switch is a head. It is provided near the pipe, the head pipe has a hole on the rear side, and the rod-shaped body is configured to be able to protrude and retract into the head pipe through the hole, and when the main switch is turned off, it enters the head pipe and enters the front fork. Block the rotation of In this case, the turning of the front fork can be easily prevented when the main switch is turned off, and the handle can be locked.

Preferably, the main frame further includes a rib provided to reinforce at least one of the second central portion, the upper portion, and the lower portion. In this case, the torsional rigidity of the main frame can be improved.

[0020] Preferably, a plurality of ribs are provided, and accessories are provided in a space surrounded by the second central portion of the main frame and the plurality of ribs. In this case, accessories can be efficiently installed in the surplus space of the main frame, and it is possible to suppress an increase in the outer shape of the vehicle. Further, even in the case of accessories having a heating element, there are a main frame and a rib near the accessory. Therefore, these members function as heat sinks, and can cool the accessories more efficiently.

[0021] Preferably, the vehicle further includes a footrest provided near the rib at a lower portion of the main frame for placing a foot of the occupant. In this case, the footrest can be held and fixed with sufficient strength.

[0022] Preferably, an auxiliary device having a built-in heating element is provided, and a part of the outer surface of the auxiliary device is in close contact with the main frame. This allows the heat generated by the heating element to be efficiently transferred to the main frame. And the temperature rise of the auxiliary equipment can be suppressed.

[0023] Preferably, the second central portion of the main frame has a through hole, and includes an electric signal line and Z or a wire passing through the through hole. By passing the electric signal lines and the brake wires through the through holes, the radius of curvature of these electric signal lines and the like can be easily increased. Further, the main frame can be made lighter by forming the through holes.

[0024] Further, preferably, the main frame and the lya frame also have light alloy strength. In this case, a light and rigid frame can be obtained.

[0025] Preferably, a cover is provided to cover at least a part of the main frame and the lya frame, and at least one of an upper portion of the main frame, a left portion of the lya frame, and a right portion of the lya frame has the same design as the cover. Make up the surface. In this case, part of the cover can be omitted.

Brief Description of Drawings

FIG. 1 is an overall view showing a schematic configuration of a motorcycle according to an embodiment of the present invention.

FIG. 2 is a perspective view showing a schematic configuration of a vehicle body frame.

FIG. 3 is a perspective view showing a schematic configuration of a vehicle body frame.

4 is a view showing a cross section taken along line X2-X2 in FIG. 3, and is a view showing a schematic configuration of a main frame.

FIG. 5 is a view showing a schematic configuration in the vicinity of a lya frame in a XI-XI cross section in FIG. 1

FIG. 6 is a view showing a cross section taken along line X3--X3 in FIG. 3, and is a view for explaining a connection state between the main frame and the rear frame.

FIG. 7 is a perspective view showing a state where a main switch of a motorcycle is provided at a front end of a main frame.

FIG. 8 is a view showing a section taken along line X4-X4 in FIG. 7.

FIG. 9 is a view showing a cross section taken along line X5-X5 in FIG.

FIG. 10 is an enlarged view of a P part in FIG. 1, and is a perspective view showing a state where a footrest is attached to a main frame and the like.

FIG. 11 is a block diagram showing a schematic configuration of a fuel cell. Explanation of reference numerals

10 motorcycle

12 Body frame

14 Mainframe

16 Lyaframe

18 Head Knife

20 Sea Train

22 front fork

24 handle

34 sheets

36, 42 Central part

38 Upper part

40 Lower part

44 Left side

46 Right side

47 cover

48 ribs

14c, 16c, 16d, 50, 52, 86

62 rod

64, 66, 68 holes

72 wires

76 Footrest

100 Fuel cell system

102 fuel cell

108, 118 heat exchange! ^

124 controller 128 heating element

130 fans

SI, S3 gap

A9, All air flow

BEST MODE FOR CARRYING OUT THE INVENTION

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

Here, an embodiment in which the present invention is applied to a motorcycle will be described.

Note that the terms left, right, front, rear, up and down in the present invention mean left, right, front, and up and down when the occupant sits on the seat 34 of the motorcycle 10 with the steering wheel 24 facing upward (see FIGS. 1 and 3). . The left-right direction is the same as the vehicle width direction, and the front-rear direction is the same as the axle direction.

Referring to FIG. 1, a motorcycle 10 according to one embodiment of the present invention is configured as, for example, a starter and includes a body frame 12.

As shown in FIGS. 2 and 3, the vehicle body frame 12 is provided at a main frame 14, a lya frame 16 connected to a rear end of the main frame 14, and a front end of the main frame 14. It includes a head pipe 18 and a seat rail 20 provided at the rear end of the rear frame 16. The body frame 12 extends back and forth from the head pipe 18 to the seat rail 20 and is formed in a substantially “U” shape. In other words, the body frame 12 has an underbone type frame structure.

[0031] The head pipe 18 is formed in a hollow cylindrical shape, and the upper half of a front fork 22 is rotatably inserted into the head pipe 18. A handle 24 is attached to the upper end of the front fork 22. The lower end of the front fork 22 rotatably supports the front wheel 26.

[0032] A front end of a rear arm 28 extending in the front-rear direction is connected to a lower end of the rear frame 16 or a rear end of the main frame 14. At this time, the rear arm 28 is connected rotatably in the vertical direction about the connection portion as a fulcrum. An electric motor 29 is provided inside the rear arm 28. The rear end of the rear arm 28 rotatably supports the rear wheel 30. An intermediate portion in the longitudinal direction of the rear arm 28 and a rear end of the rear frame 16 are connected by a rear cushion 32. [0033] The seat rail 20 is integrally provided at the rear end of the lary frame 16, for example, by welding. On the seat rail 20, a seat (saddle) 34 or the like is mounted as a seat for a passenger to sit on.

[0034] Next, the body frame 12 will be described in detail.

Referring to FIGS. 2 and 3, main frame 14 includes a plate-shaped central portion 36, an upper portion 38, and a lower portion 40, respectively. The central portion 36 also extends obliquely downward at the front end of the main frame 14, extends substantially horizontally in the rearward direction, and is formed wide in the vertical direction. The upper part 38 extends along the upper end of the central part 36 and is formed wide in the left-right direction (vehicle width direction). The lower portion 40 extends along the lower end of the central portion 36 and is formed wide in the left-right direction. Therefore, in the main frame 14, the upper portion 38 and the lower portion 40 are formed wider in the left-right direction than the central portion 36. That is, as shown in FIG. 4, the main frame 14 is formed to have an “I” cross section in a plane perpendicular to the direction in which the main frame 14 extends.

The lya frame 16 includes a plate-shaped central part 42, a left part 44, and a right part 46, respectively. The central portion 42 also has a front end portion force of the rear frame 16 extending obliquely rearward and upward, and is formed wide in the left-right direction. The left side portion 44 extends along the left side of the central portion 36 and is formed wide in the front-rear direction (axle direction). The right part 46 extends along the right part of the center part 36 and is formed wide in the front-rear direction. Therefore, in the lya frame 16, the left portion 44 and the right portion 46 are formed wider in the front-rear direction than the center portion 42. That is, as shown in FIG. 5, in the lary frame 16, the cross-sectional shape on a plane perpendicular to the extending direction of the main frame 14 is formed in an “H” shape.

In this embodiment, the upper part 38 of the main frame 14 and the left part 44 and the right part 46 of the lya frame 16 form the same design surface as the cover 47 that covers the body frame 12. That is, it is arranged, for example, flush with the partial force cover 47 indicated by oblique lines in FIG. 3 and is exposed to the outside. Thereby, a part of the cover can be omitted. Note that the cover 47 covers at least a part of the main frame 14 and the lary frame 16.

A bending moment is applied to the frame 14 and the lyaframe 16 about an axis extending in the left and right directions of the motorcycle 10 due to the weight of the rider and the like. This bending moment is The frame 16 is smaller than the frame 14. The main reason is that the riak cushion 32 absorbs the weight and the like of the occupant.

Further, a rib 48 is formed on the main frame 14.

As shown in FIG. 2, the main frame 14 is curved with respect to a straight line L connecting the front end and the rear end. The main frame 14 is provided with a plurality of ribs 48 substantially orthogonal to the straight line L and separated from each other in the direction in which the main frame 14 extends. The ribs 48 can reinforce the central portion 36, the upper portion 38 and the lower portion 40 of the main frame 14. When the motorcycle 10 is running or the like, a torsional moment centering on the straight line L is applied to the main frame 14, and the torsional moment may cause the main frame 14 to be greatly twisted and deformed. The ribs 48 can increase the rigidity against this torsional moment.

A through hole 50 is formed at the front end of the central portion 36 of the main frame 14 and at a substantially middle portion in the vertical direction. In the through hole 50, a main switch 58 (see FIG. 7 and the like) described later is arranged.

Further, an oval through-hole 52 extending in the front-rear direction is provided slightly near the rear end of the central portion 36 of the main frame 14 to facilitate passage of electric signal lines and the like.

Since the main frame 14 has a structure of a so-called fixed beam at both ends to which both ends thereof are fixed, the main frame 14 has a front end portion (near a joint portion with the head pipe 18) at the main frame. A larger bending moment is applied than in the middle part in the stretching direction of No. 14. Therefore, a reinforcing member 54 is formed at the front end of the main frame 14. The reinforcing member 54 is provided integrally with the main frame 14 above the front end of the main frame 14. An upper portion 56 having the same width as the upper portion 38 is formed at the upper end of the reinforcing member 54.

[0042] Such a vehicle body frame 12 is formed by a structure such as die casting or the like, for example, by using a light alloy such as an aluminum alloy. The main frame 14 is formed using a plurality of dies (for example, dies) that move in the left-right direction. The lya frame 16 is formed using a plurality of dies (for example, dies) that move in a direction perpendicular to a plane including the left-right direction and the extending direction of the lya frame 16 (in an oblique front-rear direction). Therefore, the main frame 14 is formed of a plane extending through the center of the body frame 12 in the left-right direction and extending in the up-down direction and the front-rear direction of the body frame 12, for example. In the lya frame 16, the parting surface (matching surface) 1S of each mold is formed by a plane extending in the extending direction and the left-right direction of the lya frame 16.

Next, the connection between the main frame 14 and the lary frame 16 will be described.

Referring to FIG. 6, at the rear end of main frame 14, respective end faces 14a, 14b perpendicular to the left-right direction are provided at a predetermined distance D in the left-right direction. At the front end of the rear frame 16, respective end faces 16a, 16b perpendicular to the left-right direction are provided at a distance slightly longer than the distance D in the left-right direction. Thus, the force can be inserted between the end faces 16a and 16b of the rear frame 16 by the force of the end faces 14a and 14b of the main frame 14.

[0044] A cylindrical through hole 14c is provided between the end faces 14a and 14b of the main frame 14. A cylindrical through hole 16c perpendicular to the end face 16a is provided on the end face 16a of the lary frame 16, and a cylindrical through hole 16d perpendicular to the end face 16b is provided on the end face 16b of the lary frame 16. When the main frame 14 and the rear frame 16 are assembled to each other, the through holes 14c, 16c and 16d have substantially the same inner diameter, the through holes 14c, 16c and 16d are located coaxially.

The end face 14a and the end face 16a face each other, the end face 14b and the end face 16b face each other, and the axes of the through holes 14c, 16c and 16d are aligned with each other. In this state, a fastener B1 such as a bolt is passed through each of the through holes 14c, 16c and 16d, and the Lya frame 16 sandwiching the main frame 14 is fastened with a fastener N1 such as a nut. Then, the lya frame 16 is slightly radiused, the end faces 14a and 16a are pressed and contacted with each other, the end faces 14b and 16b are pressed and contacted with each other, and the main frame 14 and the lya frame 16 are connected to each other. Are combined.

The outer diameter of the bolt B1 is slightly smaller than the inner diameter of each of the through holes 14c, 16c and 16d. If the gap between the bolt B1 and each of the through holes 14c, 16c and 16d is large, the main frame 14 and the lya frame 16 are connected to each other in a state where the relative positional relationship between the main frame 14 and the lya frame 16 varies. There is also a force that can be done. The connection between the mainframe 14 and the lyaframe 16 as shown in FIG. 6 is performed at at least two places.

[0047] Instead of forming the main frame 14 and the lary frame 16 by a structure, for example, "I The ribs 48 may be formed by bending a "-shaped" shape member and welding the bent portion. Further, the through holes 50 and 52 may be formed by machining.

In such a vehicle body frame 12, a main switch 58 is provided in the through hole 50 of the main frame 14.

Referring to FIGS. 7 to 9, main switch 58 penetrates through hole 50 such that its rotation center axis extends in the left-right direction. For example, by inserting the key 60 into one end of the main switch 58 and rotating the key 60, the main switch 58 is turned on and off.

[0049] To the main switch 58, a rod-shaped body 62 is connected. Holes 64 and 66 are formed in the front fork 22 that passes through the head pipe 18 and the head pipe 18 at positions corresponding to the rods 62, respectively. The rod body 62 is configured to be able to protrude and retract into the head pipe 18 through the hole 64, that is, to be able to enter and exit the hole 66 of the front fork 22 through the hole 64. When the main switch 58 is turned off, the rod-shaped body 62 enters the hole 66 through the hole 64 to prevent the front fork 22 from rotating. As a result, the handle 24 is locked.

When the hole 64 is formed in the head pipe 18, first, the holes 68 and 64 are formed so that the front side force of the head pipe 18 also moves toward the rear side, and then the lid 70 is filled in the hole 68. In this way, a desired hole 64 can be easily formed.

As shown in FIG. 10, a through hole 52 formed in the central portion 36 of the main frame 14 has an electric signal line and a wire for transmitting signals and power for operating the motorcycle 10. Key is inserted. In this embodiment, a wire 72 for driving the rear wheel brake of the motorcycle 10 is inserted. Further, by forming the through holes 52, the main frame 14 can be made lighter. The outer surface of the wire 72 is fixed to the central portion 36 of the main frame 14 using the bracket 74 near the through hole 52.

Referring to FIG. 10, a footrest 76 on which the rider of motorcycle 10 rests his / her feet is provided on the lower surface of lower portion 40 of main frame 14. The footrest 76 is provided near the rib 48 so as to extend in the left-right direction and protrude from the main frame 14.

The footrest 76 is fixed to the main frame 14 using a plate-like support member 78. Specifically, the footrest 76 is held by a “U” -shaped holding portion 80 formed at an intermediate portion of the support member 78, and is sandwiched between the lower portion 40 of the main frame 14 and the support member 78. . This state In this state, the support member 78 is fixed to the lower surface of the main frame 14 with fasteners B3 and B5 such as bolts.

[0054] Here, two bolts B3 arranged in the left-right direction are provided on the rear side of the support member 78, and one bolt B5 is provided on the front side. The front bolt B5 is spaced apart from the rib 48 by V, but has sufficient mounting strength by being provided at the center in the left-right direction of the "I" -shaped main frame 14. The two bolts B3 on the rear side have a sufficient mounting strength by being provided substantially immediately below the rib 48.

[0055] In mounting the footrest 76, the front side may be fixed with two bolts B3, and the rear side may be fixed with one bolt B5. Also, if the ribs 48 are present at a fine pitch, it may be fixed with two bolts B3 on each side.

Returning to FIGS. 2 and 3, the seat rail 20 includes a knob 82 and a plate-like member 84. In addition to the sheet 34, a seat lock, a handle standing, a seat for mounting a fuel tank, and a lighting device are provided. Used as a seat for mounting. Handle standing is a part where the passenger places his hand when temporarily lifting the motorcycle 10 in order to erect the stand of the motorcycle 10. Lighting devices include, for example, tail lamps, turn signals, and brake lamps.

The motorcycle 10 includes a fuel cell system 100 as shown in FIG.

The motorcycle 10 uses the electric power generated by the fuel cell system 100 to rotate, for example, an electric motor 29 provided inside the rear rim 28 to rotate and drive the rear wheel 30.

Referring to FIG. 11, fuel cell system 100 uses methanol (CH OH) aqueous solution as fuel.

Three

The direct methanol fuel cell system includes a fuel cell 102.

The fuel cell (fuel cell stack) 102 includes unit cells that can generate electric energy by an electrochemical reaction between an aqueous methanol solution and oxygen. In order to increase the voltage of the generated electric energy, a plurality of unit cells are stacked (stacked), and these unit cells are surrounded by a housing, whereby the fuel cell 102 is configured.

[0059] Inside the fuel cell 102, a methanol aqueous solution containing about 4% (mass ratio) of methanol is supplied as a fuel as shown by an arrow A1, and an air pump is shown as an arrow A3. Air is supplied from 104. In the fuel cell 102, the supplied methanol aqueous solution Electrical energy is generated by an electrochemical reaction with oxygen in the air. From the inside of the fuel cell 102, as shown by an arrow A5, moisture generated by the generation of electric energy and air not used for the generation of the electric energy are discharged, and as shown by an arrow A7. In addition, the carbon dioxide generated by the generation of electric energy and the aqueous methanol solution having a low concentration (about 2.5% by mass) due to the generation of electric energy are discharged.

The aqueous methanol solution, which is also discharged from the fuel cell 102 as indicated by arrow A7, is supplied to and stored in the aqueous methanol solution tank 106. The carbon dioxide is released to the atmosphere via a path (not shown). The water, which is also discharged from the internal force of the fuel cell 102 as shown by the arrow A5, is cooled by the heat exchange 108 and then supplied to and stored in the water tank 110. The air is released to the atmosphere through a path (not shown).

[0061] The water stored in the water tank 110 is supplied to the methanol aqueous solution tank 106 through the valve 112. Further, for example, a high-concentration methanol aqueous solution containing about 50% (mass ratio) of methanol is stored, and a high-concentration methanol aqueous solution is supplied from a fuel tank 114 to a methanol aqueous solution tank 106 through a valve 116.

[0062] In the path for supplying the aqueous methanol solution from the aqueous methanol tank 106 to the fuel cell 102, heat exchange 118 for cooling the aqueous methanol solution, a pump 120 for sending the aqueous methanol solution to the fuel cell 102, A concentration sensor 122 for detecting the concentration of methanol in the aqueous solution is provided.

When the fuel cell system 100 operates to generate electric energy, the fuel cell 102 generates heat and the temperature inside the fuel cell 102 becomes high. Accordingly, a high-temperature aqueous methanol solution is supplied from the fuel cell 102 to the aqueous methanol solution tank 106, and the temperature of the aqueous methanol solution stored in the aqueous methanol solution tank 106 becomes higher than the temperature of the atmosphere. In this situation, in order to also cool the internal force of the fuel cell 102, an approximately 4% aqueous methanol solution to be supplied from the methanol aqueous solution tank 106 to the fuel cell 102 is pre-cooled by heat exchange 118, and the cooled methanol is cooled. The aqueous solution is supplied into the fuel cell 102. By passing the cooled aqueous methanol solution through the fuel cell 102, the fuel cell 102 can be cooled from the inside. [0064] The concentration of methanol detected by the concentration sensor 122 is input to the controller 124. The controller 124 determines a value based on the input concentration value and a value (the amount of the methanol aqueous solution stored in the methanol aqueous solution tank 106) input from a liquid level detection sensor (not shown) provided in the methanol aqueous solution tank 106. Thus, the opening degree of the valve 112 and the valve 116 is controlled. As a result, the concentration of the aqueous methanol solution (concentration of methanol) stored in the aqueous methanol solution tank 106 is controlled to 4% and the amount of the aqueous methanol solution stored in the aqueous methanol solution tank 106 is adjusted to an appropriate amount. You.

[0065] Such a fuel cell system 100 is arranged along the body frame 12.

[0066] Auxiliary equipment is provided in a portion surrounded by the central portion 36, the upper portion 38, the lower side portion 40, and the rib 48 of the main frame 14, and a controller 124 is provided at a substantially intermediate portion of the main frame 14, for example. (See Figure 3 and Figure 4).

The accessories include various sensors, various pumps, and the like, in addition to the controller 124.

As shown in FIG. 4, the controller 124 includes a housing 126 and a heating element 128 built in the housing 126. A part of the outer surface of the housing 126 is brought into close contact with the main frame 14. For example, the housing 126 is formed in a hollow rectangular parallelepiped shape, and one of the six outer surfaces having the largest area is brought into contact with the main frame 14. At this time, the heating element 128 is brought into close contact with the inner surface located on the back side of the one surface. As described above, it is preferable that a part of the outer surface of the auxiliary equipment having a built-in heat-generating electronic component be closely attached to the main frame 14!

As shown in FIG. 5, a fuel cell 102 is provided on the front side of central portion 42 of lya frame 16, and a heat exchanger 118 is provided on the rear side. That is, the fuel cell 102 is provided in the vicinity of the heat exchanger 118 with the lary frame 16 interposed therebetween. Further, the fuel cell 102 and the heat exchanger 118 are arranged so as not to protrude outward in the left-right direction from the left part 44 and the right part 46, and are located below the seat 34 of the motorcycle 10. Further, a cover 47 is provided around the fuel cell 102 and the heat exchanger 118. A portion of the frame 16 located between the fuel cell 102 and the heat exchanger 118 is provided with a through-hole 86 through which the airflow generated by the fan 130 passes.

[0069] The fuel cell system 100 includes a fan 130 as an air flow generating means for generating a flow of air for cooling the fuel cell 102 and the heat exchanger 118. As shown in Figure 5, The heat exchanger 130 is provided behind the fuel cell 102 and the heat exchange 118 and in the vicinity of the heat exchange 118. A cover 132 is provided so as to surround the fan 130. The fan 130 can generate a directional airflow from the fuel cell 102 to the heat exchanger 118. That is, the fuel cell 102 and the heat exchange 118 are cooled by creating an airflow passing through the through-hole 86 of the lyaframe 16 by suction by the fan 130.

The through-hole 86 is formed, for example, in a circular shape as shown in FIG. Thereby, concentration of stress on the rear frame 16 can be prevented. Further, the center of the through-hole 86, whose inner diameter of the through-hole 86 is substantially equal to the outer shape of the wing of the fan 130, substantially coincides with the rotation center of the wing of the fan 130. That is, the center of the through hole 86 is located on or near the extension of the rotation center axis of the blade of the fan 130. Then, the fan 130 can efficiently extract air from around the fuel cell 102 through the through hole 86.

[0071] The air enters the cover 47 with a slight gap in the cover 47 and the lower force of the sheet 34, so that the suction by the fan 130 becomes possible.

The heat exchange 118 is an air flow that is cooled by the air flow used for cooling the fuel cell 102 (indicated by an arrow A9 in FIG. 5) and generated by the fan 130, It is also cooled by direct airflow (indicated by the arrow All in FIG. 5) from the outside air to the heat exchanger 18 directly.

[0073] The amount of airflow (indicated by arrow A9) used for cooling fuel cell 102 is smaller than the amount of airflow (indicated by arrow All) directly from outside air to heat exchange l18. The fuel cell system 100 is configured to increase the number of fuel cells.

That is, for example, by providing the fuel cell 102 at a slight distance from the central portion 42 of the lyaframe 16, a gap S1 is formed between the fuel cell 102 and the central portion 42. Further, since the heat exchange 118 is provided slightly apart from the central portion 42, a gap S3 is formed between the heat exchange 118 and the central portion 42. By appropriately setting the size (for example, the separation distance) of the gap S1 and the gap S3, the amount of airflow used for cooling the fuel cell 102 and the amount of air directly from the outside air to the heat exchanger 118 can be increased. The amount of incoming airflow is adjusted.

[0075] In addition, both ends of the outer surface on the central portion 42 side of the heat exchange 118 protrude toward the central portion 42 side, respectively. A protruding flange portion 134 is provided, and the size of the gap S3 is adjusted by the flange portion 134.

[0076] In such a fuel cell system 100, the fuel cell 102 is externally cooled by the fan 130 while the fuel cell 102 is operating. At the same time, the internal temperature of the fuel cell 102 is also cooled by cooling the methanol aqueous solution supplied from the methanol aqueous solution tank 106 to the fuel cell 102 with the heat exchanger 118 and the fan 130.

[0077] The rate of contribution to cooling of the fuel cell 102 is generally greater in the case of cooling from the inside by the heat exchange 118 than in the case of cooling of the external force of the fuel cell 102.

As described above, according to the fuel cell system 100, the heat exchanger 118 is provided near the fuel cell 102. Then, to cool the air flow around the fuel cell 102 for cooling the fuel cell 102 also with external force and the heat exchange ^ 118 capable of cooling a medium (aqueous methanol solution) for cooling the fuel cell 102 with internal force. And a single fan 130 to cool the fuel cell 102. Therefore, the fuel cell 102 can be efficiently cooled with a simple configuration.

At this time, the fan 130 generates a directional airflow from the fuel cell 102 to the heat exchanger 118. That is, the fuel cell 102 and the heat exchange 118 are arranged in the direction in which the air flows. Then, it is supplied to the air heat exchange 118 used for cooling the fuel cell 102 through the periphery of the outside of the fuel cell 102 and used for cooling the methanol aqueous solution. In this way, the outside of the fuel cell 102 and the heat exchange 118 can be efficiently cooled in order by the one-way air flow.

In particular, since fuel cell 102, heat exchange ^^ 118 and fan 130 are arranged substantially in series, the flow of air passing through fuel cell 102 and heat exchange ^^ 118 is Can be generated efficiently.

[0081] Further, since the through hole 86 is provided in the central portion 42 of the lya frame 16, air flows smoothly from the fuel cell 102 to the heat exchanger 118, and the air flows between the outside of the fuel cell 102 and the heat exchanger 118. The passing aqueous methanol solution can be efficiently cooled.

[0082] Furthermore, due to the airflow generated by fan 130, the amount of heat taken away from outside of fuel cell 102 is smaller than the amount of heat taken away from heat exchange ^^ 118. Immediately after passing through the side, the temperature of the air is slightly higher than that of the outside air. Therefore, even if the air that has passed around the outside of the fuel cell 102 is supplied to the heat exchanger 18, it is possible to sufficiently cool the aqueous methanol solution and pass through the heat exchanger 118 and the outside of the fuel cell 102. And the aqueous methanol solution can be efficiently cooled.

[0083] The heat exchange 118 is cooled by the airflow used for cooling the fuel cell 102, and is also an airflow generated by the fan 130. It is also cooled by the incoming airflow. In addition, the amount of airflow used for cooling the fuel cell 102 is larger than the amount of airflow that directs external heat to the heat exchange 118. Therefore, the fuel cell 102 can be reliably cooled from the outside, and the aqueous methanol solution can be efficiently cooled by the heat exchange 118.

Further, fan 130 forms an air flow from front fuel cell 102 to rear heat exchange 118, that is, an air flow in which the front force of motorcycle 10 also moves toward the rear. You. Therefore, the flow direction of the air formed by the fan 130 and the flow direction of the air generated by the traveling of the motorcycle 10 substantially coincide with each other, and when the motorcycle 10 is traveling, the outside of the fuel cell 102 and the heat flow therethrough. The aqueous methanol solution passing through the commutation 118 can be efficiently cooled.

[0085] A fan 130 is provided on the rear side of the heat exchanger 118 provided on the rear side of the fuel cell 102. In this case, the installation of the fan 130 and the replacement of the fan 130 are facilitated as compared with the case where the fan 130 is installed between the fuel cell 102 and the heat exchanger 118. Further, compared with the case where the fan 130 is installed on the front side of the fuel cell 102, it is easier to secure a wider space for mounting the legs of the occupant of the motorcycle 10.

[0086] Furthermore, by adjusting the size of each of the gap S1 and the gap S3, the amount of air flow used for cooling the fuel cell 102 and the external air force also directly affect the heat exchange 118. The amount and proportion can be adjusted. Therefore, it becomes easy to appropriately set the ratio of these air flow rates.

Also, by forming the cross section of the lower frame 16 on the lower side of the seat 34 into an “H” shape, the distance between the lower frame 16 and the fuel cell 102 in the left-right direction (vehicle width direction) of the motorcycle 10 is also increased. A gap can be formed in the space. Therefore, air flows efficiently near the outside of the fuel cell 102, The cooling effect of the fuel cell 102 can be increased.

Further, the fuel cell 102 and the heat exchanger 118 are installed inside the left side portion 44 and the right side portion 46 of the L-frame 16 having an “H” cross section. Therefore, heat exchange with fuel cell 102 1

18 are protected from external force generated when the motorcycle 10 falls down, and are not easily damaged.

Further, according to the fuel cell system 100, since the aqueous methanol solution is directly supplied to the fuel cell 102, a fuel reformer is not required and the configuration of the fuel cell system 100 is simplified.

Further, the aqueous methanol solution supplied to the fuel cell 102 is used as a medium (refrigerant) for cooling the fuel cell 102 from the inside. Therefore, the cooling structure of the fuel cell system 100 can be simplified without having to separately provide a device for cooling and circulating another refrigerant.

[0091] Further, since the configuration of the fuel cell system 100 can be simplified, the fuel cell system 100 can be suitably used for the motorcycle 10 in which the installation space of the device is limited.

[0092] Further, among the units constituting the fuel cell system 100, the relatively large fuel cell 102 and the heat exchange ^^ 118 are placed under the seat 34 of the motorcycle 10 having a relatively large space. Provided before and after the central part 42 of 16. Therefore, the fuel cell 102 and the heat exchanger 118 can be easily installed. Further, since the heavy fuel cell 102 is disposed near the center of the motorcycle 10, the moment of inertia of the motorcycle 10 with respect to the center of gravity can be reduced.

[0093] Lya frame 16 is formed in a cross-sectional "Η" shape. That is, the lya frame 16 has a central portion 42 that is wide in the left-right direction, and a left portion 44 and a right portion 46 that extend along both left and right ends of the central portion 42 and are formed wider in the front-rear direction than the central portion 42. It is composed of Therefore, appropriate rigidity according to the bending moment applied to the lya frame 16 can be ensured while having a light and simple shape. Further, as described above, a space for arranging the auxiliary equipment and the like of the motorcycle 10 on the front side and the rear side of the rear frame 16 can be easily secured.

[0094] On the other hand, the main frame 14 is formed in an "I" shape. That is, the upper part 38 and the lower part 40 are formed wider in the left-right direction than the central part 36, and the central part 36 is formed wider in the vertical direction. Therefore, the moment of inertia of the main frame 14 (the moment of inertia relative to the weight of the occupant and the motorcycle 10; Second moment of area). In addition, although it has a simple shape, it can be made lighter than before and can easily secure rigidity.

[0095] Therefore, the entire body frame 12 can be lightened, and rigidity corresponding to each part of the body frame 12 and a space for installing auxiliary equipment and the like can be secured.

[0096] The main frame 14 is provided with a main switch 58 of the motorcycle 10. Therefore, a bracket, for example, provided on the side of the head pipe 18 for separately attaching the main switch 58 is not required. This facilitates the handling of wires (such as brake wires and wire harnesses) around the handle 24.

[0097] The main switch 58 is provided near the head pipe 18 and at an intermediate portion in the vertical direction at the front end of the vehicle body frame 12. As described above, the main switch 58 can be provided at a position where the passenger can easily operate. Further, the secondary moment of area (secondary moment of area with respect to the axis of the motorcycle 10 extending in the left-right direction) of the body frame 12 due to the attachment of the main switch 58 can be minimized.

[0098] Further, the main frame 14 can be easily formed by die casting using each mold that moves in the left-right direction. The lya frame 16 can be easily formed by die-casting using a die that moves in a direction perpendicular to a plane including the left-right direction and the extending direction of the lya frame 16. At this time, the stroke of each mold can be reduced to make each mold smaller.

That is, the main frame 14 is curved and extends from the front end to the rear end, and has a substantially constant width in the left-right direction. Also, the width of the main frame 14 in the left-right direction is smaller than the length in the front-rear direction and the height in the vertical direction. Therefore, the stroke of each mold forming the main frame 14 can be reduced.

[0100] Also in the Lya frame 16, the width force in a direction perpendicular to a plane including the left-right direction and the extending direction in the Lya frame 16 is smaller than the width in other directions (for example, the left-right direction). Therefore, the stroke of each mold forming the lary frame 16 can be reduced.

[0101] Further, main frame 14 is formed in an "I" shape, and ribs 48 provided on main frame 14 also extend in the left-right direction. Therefore, even if the main frame 14 is formed by die-casting using a mold that moves in the left-right direction together with the ribs 48, undercutting does not easily occur. Seats and through holes for mounting the main switch 58 are provided on the main frame 14. Similarly, undercutting is unlikely to occur.

[0102] Also, the lary frame 16 is also formed in an "H" shape, so that undercutting is unlikely to occur even when formed by die-casting using the moving mold as described above.

[0103] Therefore, the configuration of each mold can be simplified, and the main frame 14 can be easily manufactured.

[0104] The hole 64 of the head pipe 18 is preferably formed as follows.

First, the main frame 14 is formed simultaneously and integrally with the head pipe 18 by, for example, die casting. Thereafter, holes 68 and 64 are formed by, for example, a mechanical machine of a drill from the front side to the rear side of the head pipe 18, and a lid 70 is filled in the hole 68. By performing such processing, the holes 64 can be easily provided as compared with the case where only the holes 64 on the rear side of the cylindrical head pipe 18 are formed.

[0105] If the hole 64 for the handle lock is to be formed by die-casting together with the main frame 14, an undercut occurs and the configuration of the mold becomes complicated. However, if the holes 64 are provided in a later step as described above, the configuration of the mold can be simplified.

[0106] Further, a seat rail 20 for installing the seat 34 of the motorcycle 10 can be integrally provided, for example, by welding at the rear end of the lya frame 16. Accordingly, the seat rail 20 having such a shape that an undercut occurs when formed by die casting can be easily provided on the rear frame 16. In addition, since the welding process that requires relatively many man-hours can be minimized, the manufacturing cost of the body frame 12 can be reduced.

In addition, for the controller 124 including the heating element 128 which is an electronic component that generates heat, a part of the outer surface of the housing 126 is brought into close contact with the main frame 14. Thus, the heat generated by the heat generating element 128 can be efficiently transmitted to the main frame 14, and the temperature rise of the controller 124 can be suppressed. Further, the main frame 14 has an upper portion 38, a lower portion 40, and a rib 48 near the controller 124 having the heating element 128. Therefore, these members function as heat sinks, and can cool controller 124 more efficiently. The same applies to other devices that have electronic components that generate heat. [0108] Further, since the footrest 76 is provided near the rib 48 on the lower surface of the lower portion 40 of the main frame 14, the footrest 76 can be held and fixed with sufficient strength.

[0109] In the main frame 14, accessories for the motorcycle 10 are provided in recesses formed by the ribs 48. Therefore, the auxiliary equipment can be efficiently installed in the surplus space of the vehicle body frame 12, and the external shape of the motorcycle 10 can be suppressed from increasing.

[0110] Further, when the brake wire or the like is used for the motorcycle 10, it is desirable that the radius of curvature be as large as possible. If the radius of curvature is small, for example, the outer sheath of the wire and the core wire come into contact due to a large contact pressure, the frictional force between the outer sheath of the wire and the core wire increases, and the power transmission efficiency and life of the wire become shorter. It is.

In this embodiment, a through hole 52 is provided in the central portion 36 of the main frame 14, and a wire 72 for a rear wheel brake passes through the through hole 52. Therefore, when the wire 72 extends from the brake lever provided on the left side of the handle 24 of the motorcycle 10 to the rear wheel brake provided on the left side of the rear wheel 30 of the motorcycle 10, the radius of curvature of the wire 72 around the handle 24 is Can be easily enlarged. Further, by providing the through holes 52, the body frame 12 can be lightened.

[0112] Further, since the through-hole 52 is provided at a substantially middle portion in the vertical direction of the main frame 14, a decrease in the second moment of area can be suppressed as much as possible.

[0113] Further, since the outer cover of the wire 72 is fixed to the main frame 14 using the bracket 74 near the through hole 52, the outer cover of the wire and the main frame 14 may rub against each other around the through hole 52. Can be prevented.

[0114] Furthermore, by forming the main frame 14 and the lary frame 16 with a light alloy, a light and rigid frame can be obtained.

[0115] In the fuel cell system 100 shown in FIG. 11, instead of or in addition to the heat exchange 118 provided on the output side of the methanol aqueous solution tank 106, the fuel cell 102 and the methanol aqueous solution tank 106 A heat exchange 118 may be provided in the path (in the path indicated by arrow A7).

[0116] Further, other heat exchangers such as heat exchanger 108 shown in FIG. Let's cool the commutation ヽ.

[0117] The fan 130 generates a directional airflow from the fuel cell 102 to the heat exchange ^^ 118, but generates a directional airflow from the heat exchange 118 to the fuel cell 102. You may. The fan 130 is provided on the rear side of the fuel cell 102 and the heat exchange 118, but is provided between the fuel cell 102 and the heat exchange 118 or in front of the fuel cell 102 and the heat exchange 118. May be provided.

[0118] Further, the fuel cell 102 is provided on the front side of the central portion 42 of the lya frame 16, and the heat exchange 118 is provided on the rear side. The heat exchange 118 is provided on the front side and the fuel cell 10 is provided on the rear side. 2 may be provided.

[0119] Further, the rotation center axes of the main switch 58 and the key 60 do not necessarily need to extend in the left-right direction. If the rotation of the key 60 is facilitated, for example, the main switch 58 and the key 60 may be provided so that the rotation center axis extends in a direction intersecting the left-right direction.

[0120] Further, the lya frame 16 may be formed so that its cross-sectional shape is, for example, a shape obtained by rotating the U-shape by 90 °.

[0121] Further, the airflow generating means is not limited to a fan.

[0122] Furthermore, the cover 47 is configured to cover the left side portion 44 and the right side portion 46 of the lya frame 16.

[0123] The present invention can also be applied to a motorcycle other than the starter type vehicle, for example, a motorcycle in which the rear end of the main frame is connected to the lya frame at an intermediate portion in the extending direction of the lya frame. . Further, the present invention can be applied to vehicles other than motorcycles.

[0124] The present invention is applicable to a fuel cell system other than the direct methanol fuel cell system.

[0125] Although the invention has been described and illustrated in detail, it is clear that it is used for illustrative purposes only and is not to be construed as limiting; the spirit and scope of the invention Is limited only by the language of the appended claims.

Claims

The scope of the claims

[1] A fuel cell capable of generating electric energy by an electrochemical reaction between fuel and oxygen, a heat exchanger provided near the fuel cell and cooling a medium passing through the fuel cell,

A fuel cell system, comprising: an air flow generation unit that generates an air flow for cooling the fuel cell and the heat exchanger.

[2] The medium is an aqueous methanol solution,

The fuel cell according to claim 1, wherein the airflow generation unit includes a fan that generates a flow of air in a direction from the fuel cell to the heat exchanger or in a direction from the heat exchanger to the fuel cell. system.

[3] The fuel cell system according to claim 1, and

Equipped with a seat for passengers to sit down,

The fuel cell and the heat exchanger are disposed before and after under the seat, and the airflow generating means is provided between the fuel cell and the heat exchanger or between the fuel cell and the heat exchange. A vehicle also provided on the rear side.

[4] The fuel cell system according to claim 1,

A seat for a passenger to sit down, and

A plate-shaped member provided below the seat portion, formed wide in the left-right direction, and extends at least in the up-down direction;

The fuel cell is provided on the front side of the plate member,

The heat exchanger is provided on the rear side of the plate-shaped member,

The air flow generating means is provided on the rear side of the heat exchanger,

A vehicle, wherein a through hole is provided in the plate-shaped member at a position between the fuel cell and the heat exchanger to allow the air flow generated by the air flow generation means to pass therethrough.

[5] The heat exchanger is cooled by the airflow used for cooling the fuel cell, and is an airflow generated by the fan, which is directly directed from the outside air to the heat exchanger. And the amount of air flow used to cool the fuel cell 5. The vehicle according to claim 4, wherein the vehicle is configured to have an amount of airflow from the outside air directly toward the heat exchange ^^.

[6] A plate-shaped first central portion extending obliquely rearward upward and wide in the left-right direction, and extends along both left and right end portions of the first central portion and becomes wide in the front-rear direction, respectively. The vehicle according to claim 4, further comprising a lya frame having a plate-shaped left portion and a right portion formed, wherein the first central portion is the plate member.

[7] A plate-like second central portion extending at least in the front-rear direction and formed wide in the vertical direction, and a plate extending along both the upper and lower ends of the second central portion and formed wide in the left-right direction, respectively. 7. The vehicle according to claim 6, further comprising a main frame having an upper portion and a lower portion in a shape of a circle, wherein a rear end of the main frame is connected to the lya frame.

[8] The vehicle according to claim 7, further comprising a main switch provided at the second central portion of the main frame.

[9] a head pipe formed at a front end of the main frame,

A front fork rotatably engaged with the head pipe, and

A rod-shaped body attached to the main switch,

The main switch is provided near the head pipe,

The head pipe has a hole on its rear side,

The rod-shaped body is configured to be able to protrude and retract into the head pipe through the hole, and when the main switch is turned off, the rod enters the head pipe and prevents the front fork from rotating. The vehicle described.

[10] The main frame according to claim 7, wherein the main frame further includes a rib provided to reinforce at least one of the second central portion, the upper portion, and the lower portion. vehicle.

[11] The rib is provided in a plurality,

11. The vehicle according to claim 10, further comprising accessories arranged in a space surrounded by the second central portion of the main frame and the plurality of ribs.

12. The vehicle according to claim 7, further comprising a footrest provided on the lower side of the main frame near the rib for resting a foot of the occupant.

13. The vehicle according to claim 7, further comprising auxiliary equipment having a built-in heating element, wherein a part of an outer surface of the auxiliary equipment is in close contact with the main frame.

[14] The second central portion of the main frame has a through hole,

The vehicle according to claim 7, further comprising an electric signal line and a Z or a wire passing through the through hole.

15. The vehicle according to claim 7, wherein the main frame and the lya frame also have light alloy strength.

[16] A cover for covering at least a part of the main frame and the Lya frame, wherein at least one of the upper part of the main frame, the left part of the Lya frame, and the right part of the Lya frame is provided. 8. The vehicle according to claim 7, wherein one of the covers has the same design surface as the cover.