JP2008126847A - Cooling structure of fuel cell electric vehicle - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a cooling structure of a fuel cell electric vehicle capable of effectively performing cooling corresponding to different heat source components. <P>SOLUTION: In the cooling structure of the fuel cell electric vehicle, a vehicle body frame comprises side frames 8, 8, a plurality of cross members 29, 38 and 44, and joint ducts provided at parts for connecting them, and is formed hollow. Each joint duct has a fan for generating cooling air in the side frame 8 and the cross members 29, 38 and 44, and has a valve for distributing the cooling air to the side frame 8, and the cross members 29, 38 and 44. A motor mounting bracket 47, a stack mounting bracket 49, and a battery mounting bracket 51 are provided so as to be capable of connecting arrangement parts of the vehicle body frame for a motor 4, a fuel cell stack 5 and a battery 6 and the vehicle body frame in a heat transfer manner. The cooling structure also has a control device 54 for controlling the fan and the valve according to the temperature state of each heat source component. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a cooling structure for a fuel cell vehicle.

In some electric vehicles and the like, a mounted traveling battery is cooled by outside air taken from the front end of the vehicle body. This battery has a hollow side frame that is arranged on the left and right sides of the vehicle body in the front-rear direction, and an external air intake port is provided at the front end of the side frame, and a discharge port is provided at the rear end. A passage branched from the side frame is connected to the provided battery storage part, and the inside of the battery storage part is cooled by outside air taken in from the side frame (see Patent Document 1).
JP 05-199881 A

By the way, since the fuel cell vehicle includes the heat source components such as the fuel cell stack and the high voltage battery as in the case of the electric vehicle, the conventional cooling structure described above can be adopted. Unlike a mounted electric vehicle, a fuel cell vehicle having different heat source components has a problem that it cannot be simply cooled in one place.
That is, since the heat source components have different heat loads for each component, it is necessary to cool each component separately. In addition, it is conceivable to provide a separate storage unit for each part for cooling, but simply cooling by directly applying external air to the heat source part restricts the arrangement of the vehicle body frame and each part, and the heat source part There is a problem that the degree of freedom of design is reduced in a fuel cell vehicle or the like having a large amount of fuel.

  Accordingly, an object of the present invention is to provide a cooling structure for a fuel cell vehicle capable of effectively performing cooling corresponding to different heat source components.

In order to achieve the above object, the invention described in claim 1 is provided with a hollow side frame (for example, the side frame 8 in the embodiment) which is a vehicle body skeleton member along the front-rear direction on the left and right sides of the vehicle body. An intake port (for example, the intake port 18 and the intake port 15 in the embodiment) is provided at the front end portion of the frame, and an exhaust port (for example, the exhaust port 16 in the embodiment) is provided at the rear end portion. A hollow cross member (for example, the front front cross member 25, the diagonal cross member 29, the rear floor cross member 39, and the end floor cross member 44 in the embodiment) is disposed, and the cross member and the side frame are jointed. Duct (for example, the inlet joint duct 17, the front joint duct 30, the connection joint in the embodiment) An induct duct 34 and a passenger compartment joint duct 40, 40 ') are connected in communication to form a vehicle body frame, and the joint duct generates a cooling air in the side frame and the cross member (for example, the fan 24 in the embodiment). ) And a valve for distributing cooling air to the side frame and the cross member (for example, the valve 22 in the embodiment), and heat source components of the vehicle body frame (for example, the motor 4 and the fuel cell stack in the embodiment). 5. Battery 6) A heat transfer plate (for example, motor mounting bracket 47, stack mounting bracket 49, battery mounting bracket 51 in the embodiment) for connecting heat between the arrangement part and the vehicle body frame is provided, and each heat source Depending on the temperature conditions of the parts, Controller for controlling the serial valves (e.g., the control device 54 in the embodiment), characterized in that a.
By comprising in this way, the function as a duct for cooling can be given to the body frame as a body frame member.

  According to the first aspect of the present invention, since the vehicle body frame as the vehicle body skeleton member can be provided with a function as a cooling duct, the cooling capacity of the entire vehicle can be improved. There is. Therefore, since the existing cooling system can be reduced in size, it is possible to reduce the size and weight.

Next, embodiments of the present invention will be described with reference to the drawings. As shown in FIG. 1, a fuel cell vehicle 1 includes a traveling motor (drive motor (DM)) 4 in a power plant room 3 at the front of a vehicle body separated on the front side of a dash panel 2. A fuel cell stack (FC) 5 is disposed under the floor tunnel, and a battery (BAT) 6 is disposed behind the fuel cell stack 5.
Here, the fuel cell stack 5 performs power generation by an electrochemical reaction between supplied hydrogen and oxygen, and travels by driving the motor 4 with the electric power generated by the power generation. The fuel cell stack 5 is disposed below the floor tunnel portion on the rear floor of the rear part of the vehicle body, and generates power using hydrogen gas supplied from a hydrogen tank provided at the rear part of the vehicle body and oxygen in the air supplied from a compressor provided at the front part of the vehicle body. I do.

As shown in FIGS. 2 and 3, the fuel cell vehicle 1 includes hollow side frames 8 and 8 that are body frame members along the front-rear direction on the left and right sides of the vehicle body. Each side frame 8 includes a front frame 9 disposed at the lower part of the power plant room 3, a front frame 10 and a rear frame 11 disposed in the front and rear of the vehicle interior, and a rear frame 12 below the luggage room. And. The front frame 9, the vehicle compartment front frame 10, the vehicle compartment rear frame 11, and the rear frame 12 are formed of a hollow aluminum material.
The front frame 10 has a front end portion that communicates with the rising front frame 9 via a step portion 13, and the rear frame 12 has a front end portion that falls to the front side via a step portion 14 and communicates with the rear compartment frame 11. Yes.
An intake port 15 is formed at the front end of the left and right front frames 9, and an exhaust port 16 is formed at the rear ends of the left and right rear frames 12.

  An inlet joint duct 17 is attached to the front ends of the left and right front frames 9. As shown in FIG. 4, the intake joint duct 17 is a member made of a hollow aluminum material provided with an intake port 18 on the front side and a rear opening 19 on the rear side. A mold valve unit 20 is fixed by a bolt 21, and the intake port 18 is configured to be opened and closed by a valve 22. A fan unit 23 is fixed to the rear opening 19 with bolts 21 so that cooling air is generated by the fan 24 and can be distributed downstream from the rear opening 19. Here, a front front cross member 25 made of a hollow aluminum material, which is a vehicle body skeleton member, is joined between the inlet joint ducts 17 at the front end portions of the left and right front frames 9. The fan unit 23 and the valve unit 20 are inserted and assembled from the upper insertion port 26 of the intake port joint duct 17. Here, the fan unit 23 is provided with a fan motor 27 for driving the fan 24, and the valve unit 20 is provided with a valve drive motor 28 for driving the valve 22 (the same applies hereinafter).

  Between the left and right front frames 9, 9, hollow diagonal cross members 29, 29 made of an aluminum material, which is a vehicle body frame member, are arranged at the rear end of the front frame 9 obliquely inward and forward, respectively. The front end portions of the oblique cross members 29 are connected to the front joint ducts 30 respectively. The rear end portion of each oblique cross member 29 is connected by a hollow support cross member 31 made of an aluminum material which is a vehicle body skeleton member.

As shown in FIG. 6, the front joint duct 30 is a member made of a hollow aluminum material having a front opening 32 on the front side and side opening parts 33, 33 on both sides, and each side opening 33. The butterfly type valve unit 20 for opening and closing them is fixed by bolts 21, and each side opening 33 can be opened and closed by the valve 22. A fan unit 23 is fixed to the front opening 32 of the front joint duct 30 with a bolt 21 so that cooling air can be generated by the fan 24 and distributed downstream from the side opening 33. The fan unit 23 and the valve unit 20 are assembled by being inserted from the upper insertion opening 26 of the front joint duct 30.
Connection joint ducts 34 l and 34 r are connected in communication between the rear end portion of each oblique cross member 29, the rear end portion of the front frame 9, and the front end portion of the passenger compartment front frame 10.

FIG. 5 shows the left connection joint duct 34l. Since the right connecting joint duct 34r and the left connecting joint duct 34l are opposite to each other, the left connecting joint duct 34l will be described as an example.
As shown in FIG. 5, the connecting joint duct 34l is a member made of a hollow aluminum material provided with a front opening 35 on the front side, a side opening 36 on the inner side, and a rear opening 37 on the rear side. The butterfly-type valve unit 20 that opens and closes the side opening 36 is fixed by a bolt 21, and the side opening 36 can be opened and closed by the valve 22.

  Also, a butterfly type valve unit 20 that opens and closes the front opening 35 of the connection joint duct 34 l is fixed by a bolt 21, and the front opening 35 can be opened and closed by the valve 22. The front opening 35 of the connection joint duct 34l is connected to the rear end of the front frame 9, the side opening 36 is connected to the rear end of the oblique cross member 29, and the rear opening 37 is connected to the vehicle compartment front frame 10. It is connected to the front end. The fan unit 23 and the valve unit 20 are assembled by being inserted from the upper insertion port 26 of the connection joint duct 34l.

A hollow front floor cross member 38 made of an aluminum material, which is a vehicle body skeleton member, is connected between the left and right passenger compartment front frames 10 and 10 at the rear part of the step part 13 at the front end part.
A hollow rear floor cross member 39 made of an aluminum material, which is a vehicle body skeleton member, is disposed between the front frames 10 and 10 of the respective passenger compartments, and each end of the rear floor cross member 39 and the vehicle Vehicle interior joint ducts 40 l and 40 r are connected in communication between the rear end portion of the front compartment frame 10 and the front end portion of the rear compartment frame 11.

FIG. 7 shows the left-hand compartment joint duct 40l. Since the right side joint joint duct 40r and the left side joint joint duct 40l are opposite to each other, the left side joint joint duct 40l will be described as an example.
As shown in FIG. 7, the passenger compartment joint duct 40l is a member made of a hollow aluminum material having a front opening 41 on the front side, a side opening 42 on the inside, and a rear opening 43 on the rear side. The butterfly type valve unit 20 that opens and closes the side opening 42 is fixed by a bolt 21, and the side opening 42 can be opened and closed by the valve 22.

  A butterfly-type valve unit 20 that opens and closes the rear opening 43 of the vehicle interior joint duct 40 is fixed by a bolt 21, and a side opening 42 can be opened and closed by the valve 22. The front opening 41 of the vehicle compartment joint duct 40 is connected to the rear end of the vehicle front frame 10, the side opening 42 is connected to the end of the rear floor cross member 39, and the rear opening 43 is connected to the rear of the vehicle compartment. The front end of the frame 11 is connected. The fan unit 23 and the valve unit 20 are assembled by being inserted from the upper insertion port 26 of the passenger compartment joint duct 40.

A hollow end floor cross member 44 made of an aluminum material, which is a vehicle body skeleton member, is connected to the rear end portion between the left and right passenger compartment rear frames 11, 11. A vehicle interior joint duct having the same configuration as the vehicle interior joint duct 40 described above is provided between each end of the end floor cross member 44, the rear end of the vehicle rear frame 11 and the front end of the rear frame 12. 40 '(40l', 40r ') is connected in communication. Each front opening 41 of the vehicle compartment joint duct 40 ′ is connected to the rear end of each vehicle rear frame 11, and each side opening 42 is connected to each end of the end floor cross member 44. An opening 43 is connected to the front end of each rear frame 12.
Between the left and right rear frames 12, 12, a hollow rear cross member front 45 and a rear cross member rear 46 made of an aluminum material, which is a vehicle body skeleton member, are connected to the front and rear. An exhaust port 16 is formed at the rear ends of the rear frames 12 and 12.

  Here, a pair of motor mounting brackets 47, 47 extending to the front side are joined to the oblique cross member 29, and the front end portions of the motor mounting brackets 47, 47 are configured as a motor installation portion having a bolt hole 48. Yes. Further, a pair of stack mounting brackets 49, 49 extending to the front side are joined to the front floor cross member 38, and the front end portion of the stack mounting bracket 49 is configured as a stack installation portion having bolt holes 50. A pair of battery mounting brackets 51, 51 extending to the front side are joined to the rear floor cross member 39, and the front end portion of the battery mounting bracket 51 is configured as a battery installation portion having a bolt hole 52.

  The motor mounting brackets 47 and 47 have a motor 4, the stack mounting brackets 49 and 49 have a fuel cell stack 5, and the battery mounting brackets 51 and 51 have a battery 6 to increase heat conductivity. 48, 50 and 52 are directly attached. The motor mounting bracket 47, the stack mounting bracket 49, and the battery mounting bracket 51 are all made of a material having high thermal conductivity, for example, an aluminum material.

As shown in FIG. 8, temperature sensors 53 are respectively attached to the motor 4, the fuel cell stack 5, and the battery 6, and detection signals from the temperature sensors 53 are input to a control device (ECU) 54. . Further, a wiper switch (WS) 55 is connected to the control device 54 so as to detect the operation / non-operation of the wiper.
And the fan motor 27 and the valve unit 20 of the fan unit 23 of the inlet joint duct 17, the front joint duct 30, the connection joint ducts 34 l and 34 r, and the passenger compartment joint ducts 40 l, 40 r, 40 l ′ and 40 r ′ described above. The valve drive motor 28 is connected by a control device 54 so that the drive can be controlled. Reference numeral 56 denotes a radiator (not shown in FIGS. 9 to 12).

Here, a plurality of modes are set in the control device 54 for cooling the heat source components of the fuel cell vehicle 1 so that the maximum cooling effect can be exhibited by adopting a cooling operation mode according to the operation state of the vehicle. It has become. Here, the heat source components are the motor 4, the fuel cell stack 5, and the battery 6. The motor 4 as the heat source component may include a drive circuit.
This cooling operation mode includes an overcool avoidance mode in which excessive cooling is not performed when the fuel cell system is stopped or when the outside air temperature is extremely low during rainy weather (when the wiper is activated), normal driving, etc. A normal mode in which the load on the fuel cell stack is large, a motor load large mode in the case where the motor load is large such as a long uphill, and a start mode in which the fuel cell stack load is small and the battery load is large, such as immediately after starting, are set.

The cooling operation mode will be described based on FIGS.
FIG. 9 shows the overcool avoidance mode. The conditions for selecting this mode are when the fuel cell stack 5 is not generating power, or when it is raining (the wiper switch 55 is on) and the outside air temperature is extremely low.
In such a case, if the cooling operation is performed, it is overcooled, and this needs to be prevented. Therefore, the intake port 15 of the side frame 8 is closed by closing the intake port 18 of the intake port joint duct 17 with the valve 22. Further, the fans 24 of the fan units 23 of the inlet joint duct 17 and the front joint duct 30 are stopped. Further, the side opening 33 is closed by the valve 22 of the front joint duct 30. Thereby, the cooling air does not flow into the side frame 8, and overcooling of the motor 4, the fuel cell stack 5, and the battery 6 is prevented.

  FIG. 10 shows the normal mode. The condition for selecting this mode is during normal operation when the load on the fuel cell stack 5 is large. In this case, in the right inlet joint duct 17, the inlet 18 is opened by the valve 22 to drive the fan 24, the side openings 33 are closed by the valve 22 of the front joint duct 30, and the connection joint The front opening 35 is opened by the valve 22 of the duct 34r, and the side opening 36 is closed. At this time, the intake port 18 is closed by the valve 22 in the left intake port joint duct 17.

Further, in the right side joint joint duct 40 r, the side opening 42 is opened by the valve 22, and the rear opening 43 is closed by the valve 22. Further, in the left side joint joint duct 40 l, the side opening 42 is opened by the valve 22, and the rear opening 43 is opened by the valve 22.
Further, in the left-side compartment joint duct 40 l ′ on the rear side, the side opening 42 is closed by the valve 22, and the rear opening 43 is opened by the valve 22.
Therefore, in this normal mode, the rear floor cross member 39 is cooled by the traveling wind taken from the front side, so that the load is large via the stack mounting brackets 49, 49, so that the fuel cell stack 5 that is at a high temperature is effectively used. Can be cooled. At this time, the motor 4 and the battery 6 are not exposed to the heat radiation atmosphere of the fuel cell stack 5.
Note that the fuel cell stack 5 may be cooled by cooling air flowing from the left to the right of the rear floor cross member 39.

  FIG. 11 shows the motor load large mode. This mode is selected when a very large load is applied to the motor 4. In this case, since it is necessary to cool the motor 4 effectively, the intake ports 18 are closed by the valves 22 of the left and right intake port joint ducts 17 to close the intake ports 15 of the side frames 8. Further, the fan 24 of the front joint duct 30 is driven, the side opening 33 is opened by the valve 22, and the side opening 36 is opened by the valve 22 of the left and right connecting joint ducts 34l and 34r. In the left and right passenger compartment joint ducts 40 l and 40 r, the side opening 42 is closed by the valve 22, and the rear opening 43 is opened by the valve 22. Further, the side opening 42 is closed by the valve 22 and the rear opening 43 is opened by the valve 22 in the left and right rear passenger compartment joint ducts 40 l ′ and 40 r ′.

  Therefore, in this motor load large mode, the cooling air flows through the oblique cross member 29 to which the heat of the motor 4 is transmitted by the motor mounting brackets 47, 47, and the fan 24 actively takes in the atmosphere around the motor 4. Therefore, the motor 4 can be effectively cooled. At this time, since the fuel cell stack 5 and the battery 6 are not exposed to the cooling air, they are not affected by the heat radiation atmosphere of the motor 4.

FIG. 12 shows the start mode. The condition for selecting this mode is when the fuel cell stack load is small, such as immediately after startup, and the battery load is large. In this case, in the right inlet joint duct 17, the inlet 18 is opened by the valve 22 to drive the fan 24, and the side openings 33 are closed by the valve 22 of the front joint duct 30, thereby connecting the joints. The front opening 35 is opened by the valve 22 of the duct 34r, and the side opening 36 is closed. At this time, the intake port 18 is closed by the valve 22 in the left intake port joint duct 17.
Further, in the right side joint joint duct 40r, the side opening 42 is closed by the valve 22, and the rear opening 43 is opened by the valve 22.

Then, in the right-side compartment joint duct 40r ′ on the rear side, the side opening 42 is opened by the valve 22, and the rear opening 43 is closed by the valve 22. Further, in the left side joint joint duct 40 l ′, the side opening 42 is opened by the valve 22, and the rear opening 43 is opened by the valve 22.
Therefore, in this starting mode, the end floor cross member 44 is cooled by the traveling wind taken from the front side, and thereby the battery 6 that is high temperature due to a large load is effectively cooled via the battery mounting brackets 51 and 51. it can. At this time, the motor 4 and the fuel cell stack 5 are not exposed to the heat radiation atmosphere of the battery 6.
The battery 6 may be cooled by cooling air flowing from the left to the right of the end floor cross member 44.

  According to the above-described embodiment, the side frame 8, the oblique cross member 29, the rear floor cross member 39, and the end floor cross member 44 as the vehicle body skeleton member, which is a vehicle body frame, are effectively used as a duct through which cooling air flows. In addition, the motor mounting bracket 47, the stack mounting bracket 49, and the battery mounting bracket 51 can cool the motor 4, the fuel cell stack 5, and the battery 6 that are heat source components individually without affecting each other. Can be effectively cooled. Accordingly, the degree of freedom in arrangement of the side frame 8, the oblique cross member 29, the rear floor cross member 39, and the end floor cross member 44 is not affected, and sufficient cooling performance can be secured even if the radiator 56 is downsized. The system can be reduced in size and weight.

It is side surface explanatory drawing of the fuel cell vehicle of embodiment of this invention. It is a principal part perspective view of this invention. FIG. 3 is an exploded perspective view of FIG. 2. It is a disassembled perspective view of an intake joint duct. It is a disassembled perspective view of the left connection joint duct. It is a disassembled perspective view of a front joint duct. It is a disassembled perspective view of the side compartment joint duct. It is a disassembled perspective view of the cooling system of embodiment of this invention. It is a top view of overcool avoidance mode. It is a top view of normal mode. It is a top view of motor load large mode. It is a top view of start mode.

Explanation of symbols

4 Motor (heat source parts)
5 Fuel cell stack (heat source parts)
6 Battery (heat source component)
8 Side frame 15 Intake port 16 Exhaust port 17 Inlet port joint duct 18 Inlet port 22 Valve 24 Fan 25 Front front cross member 29 Diagonal cross member 30 Front joint duct 34 Connection joint duct 39 Rear floor cross member 40 Car interior joint member 44 End floor cross member 47 Motor mounting bracket (heat transfer plate)
49 Stack mounting bracket (heat transfer plate)
51 Battery mounting bracket (heat transfer plate)
54 Control device

Claims (1)

  A hollow side frame that is a vehicle body skeleton member is provided on the left and right sides of the vehicle body in the front-rear direction, an air intake port is provided at the front end of the side frame, and an exhaust port is provided at the rear end portion. A hollow cross member is disposed, and the cross member and the side frame are connected to each other by a joint duct to form a vehicle body frame. The joint duct generates cooling air in the side frame and the cross member. A heat transfer plate that includes a fan and a valve that distributes cooling air to the side frame and the cross member, and that connects the heat source component placement portion of the vehicle body frame and the vehicle body frame so as to transfer heat is provided. And a control device for controlling the fan and the valve according to the temperature condition of each heat source component. Cooling structure for a fuel cell vehicle.

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