JP7099259B2 - Fuel cell vehicle - Google Patents

Description

The present invention relates to a fuel cell vehicle.

Fuel cell vehicles require the supply and discharge of fuel gas, oxidation gas, and cooling water to the on-board fuel cells. In Patent Document 1, a fuel cell is mounted on the front side of the vehicle from the vehicle interior, and auxiliary equipment such as a compressor is mounted on the rear side of the vehicle in the vicinity of the fuel cell, so that gas and cooling water supply / discharge hoses and pipes are installed. A method for simplification has been proposed.

Japanese Unexamined Patent Publication No. 2018-41539

In the method of mounting a fuel cell or the like proposed in Patent Document 1, the mounting location of the fuel cell is near the vehicle interior. Therefore, as described below, there is a concern that the sound generated by supplying gas to the fuel cell may be recognized as noise by the vehicle driver or passengers.

At the start and end of operation of the vehicle, gas is supplied without performing power generation operation of the fuel cell in order to scaveng the gas in the fuel cell and the gas supply / exhaust pipe system. Air, which is an oxidation gas, is supplied by a compressor that operates at a steady output, and excess air that exceeds the amount of gas required for scavenging the flow path in the fuel cell bypasses the fuel cell and flows into the gas discharge pipe. become. In addition, even when the vehicle is running, in the accelerator off situation, the excess air exceeding the gas amount corresponding to the required output bypasses the fuel cell while the compressor is operated at the output at the time of accelerator off. It will flow into the gas discharge pipe. When excess air flows into the gas discharge pipe via the bypass pipe, the surplus air is discharged from the fuel cell and merges with the air (off gas) flowing through the gas discharge pipe, and then the junction between the bypass pipe and the gas discharge pipe. It collides with the pipeline of the gas, and the impact noise due to this gas collision can be generated. In addition, airflow noise may occur when air flows downstream from the confluence of the bypass pipe and the gas discharge pipe.

Since the background noise such as the noise generated by the rotation of the tire is small when the accelerator is off, when the vehicle is started, and when the vehicle is stopped, the above-mentioned impact noise and airflow noise are recognized as noise by the vehicle driver and passengers. obtain. Impact noise and airflow noise can be reduced by increasing the rigidity of the gas discharge pipe where air joins from the bypass pipe as a steel pipe or resin pipe. From the viewpoint of simplification, in the vicinity of the fuel cell, there is no choice but to adopt a flexible pipe form that can be bent, and the actual situation is that the reduction of impact noise and airflow noise is not progressing. In addition, the impact noise caused by the gas collision with the junction of the bypass pipe and the gas discharge pipe can be reduced by making the bypass pipe and the gas discharge pipe merge at a gentle angle, but around the fuel cell. Due to the design of the piping routes of various pipelines in, it is difficult to join the bypass pipe and the gas discharge pipe at a gentle angle. For this reason, it is difficult to recognize the sound generated in the gas discharge pipe as noise is generated when the gas is supplied to the fuel cell, while ensuring the freedom of piping around the fuel cell and the simplification of the piping work. It came to be requested.

The present invention can be realized as the following forms.

(1) According to one embodiment of the present invention, a fuel cell vehicle is provided. This fuel cell vehicle is connected to an oxide gas supply flow path for supplying the oxide gas to the fuel cell and an oxide gas discharge manifold of the fuel cell, and guides the oxide gas discharged from the fuel cell to the outside. The pipe is provided with a bypass pipe for connecting the oxide gas supply flow path and the oxide gas discharge pipe by bypassing the fuel cell, and the oxide gas discharge pipe is connected to the oxide gas discharge manifold. The area from the uppermost stream of the path to the area around the battery that is piped around the fuel cell is in the form of a flexible pipe, and the oxide gas discharge pipe is formed in the middle of the pipe in the form of the flexible pipe. The bypass pipe is provided by projecting a bypass pipe connection body to which the bypass pipe is connected at a sharp angle toward the downstream in the flow direction of the oxide gas flowing through the gas discharge pipe, and the bypass pipe connected to the bypass pipe connection body is the bypass pipe. The pipeline including the bypass tube projection site projected onto the inner wall of the oxide gas discharge pipe along the center line of the It is a thick pipeline. In this type of fuel cell vehicle, the oxide gas discharge pipe is in the form of a flexible pipe that can be bent in the pipeline area from the oxide gas discharge manifold of the fuel cell to the vicinity of the fuel cell. It is possible to secure the degree of freedom and the simplification of piping work. In addition to this, in this type of fuel cell vehicle, when the oxide gas flows from the oxide gas supply flow path to the oxide gas discharge pipe through the bypass pipe as the fuel cell is operated, the oxide gas passes through the oxide gas discharge pipe. It flows at a sharp angle toward the downstream in the flowing gas flow direction and collides with the conduit including the bypass tube projection portion at the protruding portion of the bypass tube connection. Impact noise may be generated due to this gas collision, but the pipeline including the bypass tube projection site and the pipeline downstream of this bypass tube projection site are thicker than the pipeline upstream of the bypass tube projection site. Since it is a pipeline, it is difficult for impact noise to leak to the outside of the oxide gas discharge pipe. In addition, since the inflow of oxidative gas into the oxidative gas discharge pipe through the bypass pipe is sharp toward the downstream in the gas flow direction through the oxidative gas discharge pipe, the impact noise itself is reduced to some extent and the bypass pipe is used. The sound of the airflow when the oxidizing gas flows downstream from the projection site can also be reduced. As a result, according to this form of the fuel cell vehicle, it is possible to make it difficult to recognize the sound generated in the oxide gas discharge pipe as noise when the fuel cell is operated.

The present invention can be realized in various aspects. For example, it can be realized in the form of a method of supplying an oxidizing gas to a fuel cell in a fuel cell vehicle, an oxidizing gas discharging pipe used for discharging the oxidizing gas from the fuel cell, a method of manufacturing the same, and the like.

It is explanatory drawing which shows the schematic structure of the fuel cell system. It is explanatory drawing which shows the state of being mounted on the vehicle about the main equipment which constitutes a fuel cell system and a gas path. It is explanatory drawing which shows 3D schematic the device positional relationship of the pipe arrangement area of the off-gas upstream side discharge pipe in FIG. It is explanatory drawing which shows the outline of the pipeline structure of the off-gas upstream side discharge pipe by cross-sectional view along the pipeline. It is a graph which shows the measurement result of the generated sound in the off-gas upstream side discharge pipe.

FIG. 1 is an explanatory diagram showing a schematic configuration of the fuel cell system 10. FIG. 2 is an explanatory diagram schematically showing how the main equipment constituting the fuel cell system 10 and the gas path are mounted on the vehicle. The fuel cell system 10 includes a fuel cell 100, a fuel gas supply circuit 200, an air supply circuit 300, an exhaust gas circuit 400, and a cooling circuit 500.

The fuel cell 100 receives the supply of the fuel gas and the oxygen-containing oxidizing gas to generate electricity, and outputs the generated power to a load (not shown), for example, a drive motor of a vehicle equipped with a fuel cell. The fuel cell 100 is mounted in the mounting area 40 on the front side of the vehicle from the vehicle compartment 30 of the vehicle 20. The mounting area 40 is opened by opening a vehicle bonnet (not shown), and maintenance and inspection around the fuel cell 100 becomes possible.

The fuel gas supply circuit 200 includes a fuel gas tank 210, a fuel gas supply flow path 220, a fuel gas exhaust flow path 230, a fuel gas circulation flow path 240, a main valve 250, a regulator 260, an injector 270, and a gas. A liquid separator 280 and a recirculation pump 290 are provided. The fuel gas tank 210 stores fuel gas. In this embodiment, hydrogen gas is used as the fuel gas.

The fuel gas supply flow path 220 is arranged so as to hang from the fuel gas tank 210 mounted on the rear side of the vehicle to the fuel cell 100, and supplies the fuel gas to the fuel cell 100. The fuel gas supply flow path 220 is provided with a main valve 250, a regulator 260, and an injector 270 from the fuel gas tank 210 side. The main valve 250 turns on / off the supply of fuel gas from the fuel gas tank 210. The regulator 260 reduces the pressure of the fuel gas to a predetermined pressure and supplies it to the injector 270. The injector 270 is an injection device that injects the fuel cell 100 by adjusting the pressure and amount of the fuel gas. In this embodiment, three injectors 270 are arranged in parallel. The number of injectors 270 is not limited to 3, and may be configured to include one injector or two or more injectors. When a plurality of injectors 270 are provided as in the present embodiment, it is possible to easily adjust the amount of fuel gas injected into the fuel cell 100 according to the amount of power generation required for the fuel cell 100.

The fuel gas exhaust flow path 230 discharges the fuel exhaust gas from the fuel cell 100. The fuel gas circulation flow path 240 is arranged so as to extend from the fuel gas exhaust flow path 230 to the fuel gas supply flow path 220, and circulates the fuel exhaust gas discharged from the fuel cell 100 to the fuel gas supply flow path 220. A gas-liquid separator 280 is arranged in the fuel gas circulation flow path 240. The fuel exhaust gas contains the fuel gas that was not consumed in the reaction, impurities such as nitrogen that has moved through the fuel cell 100, and water. As shown in FIG. 2, the gas-liquid separator 280 is arranged on the front side of the vehicle in the vicinity of the fuel cell 100, and contains water and gas (fuel gas and fuel) contained in the fuel exhaust gas passing through the fuel gas circulation flow path 240. Gas-liquid separation is performed on impurities such as nitrogen that have moved through the battery 100, and the separated liquid water is stored. A recirculation pump 290 is provided in the fuel gas circulation flow path 240. The gas containing the unconsumed fuel gas separated by the gas-liquid separator 280 is circulated to the fuel gas supply flow path 220 by the recirculation pump 290 and reused.

The air supply circuit 300 supplies an air cleaner 310, an air supply flow path 320, an air compressor 330, an intercooler 340, a stack inlet valve 350, an atmospheric pressure sensor 375, an outside temperature sensor 380, an air flow meter 385, and the like. It includes a gas temperature sensor 390 and a supply gas pressure sensor 395. The fuel cell 100 of the present embodiment uses air as the oxygen-containing oxidizing gas.

The air cleaner 310 removes dust in the air when taking in air. The air cleaner 310 and the fuel cell 100 are connected by an air supply flow path 320. The air supply flow path 320, which is the oxidation gas supply flow path, is provided with an air compressor 330, an intercooler 340, and a stack inlet valve 350 in this order from the air cleaner 310 side. The air compressor 330 compresses the air and supplies the air to the fuel cell 100 through the air supply flow path 320. Generally, when a gas is compressed, its temperature rises. This is because when the gas is compressed, it compresses against the pressure of the gas, so that work is added to the gas.

The intercooler 340 exchanges heat so that the temperature of the air compressed by the air compressor 330 and whose temperature has risen becomes substantially the same as the temperature of the fuel cell 100. That is, the refrigerant discharged from the fuel cell 100 is divided and supplied to the intercooler 340, and the temperature of this refrigerant is substantially equal to the temperature of the fuel cell 100. Therefore, the temperature of the compressed air is substantially equal to the temperature of the fuel cell 100. The temperature of the exhaust gas discharged from the fuel cell 100 is also substantially equal to the temperature of the fuel cell 100. The stack inlet valve 350 is a valve for turning on / off the supply of air to the fuel cell 100. The atmospheric pressure sensor 375 measures the atmospheric pressure. The outside air temperature sensor 380 acquires the temperature of the air before it is taken in. The air flow meter 385 measures the flow rate of the taken-in air. The supply gas temperature sensor 390 measures the temperature of the air supplied to the fuel cell 100, and the supply gas pressure sensor 395 measures the pressure of the air supplied to the fuel cell 100.

The exhaust gas circuit 400 includes an off-gas discharge pipe 410, a pressure control valve 420, a liquid water discharge pipe 430, a discharge valve 440, an oxidation gas bypass pipe 450, and a silencer 470. The off-gas discharge pipe 410, which is an oxidation gas discharge pipe, is connected to the fuel cell 100 and extends to the rear of the vehicle, and the off-gas upstream side discharge pipe 411 connected to the fuel cell 100 and the off-gas downstream side discharge pipe 412 on the downstream side thereof. The air (oxidizing gas) discharged from the fuel cell 100 is guided to the outside from the fuel cell 100 and discharged. The off-gas upstream discharge pipe 411 is a flexible tube made of rubber that is supposed to be fixed to other fixing devices at the lower end of the pipeline, and is molded using heat-resistant ethylene-propylene rubber or the like. Ru. The off-gas downstream discharge pipe 412 is in the form of a pipe that is fixed to other members at appropriate points and can maintain the pipeline locus by the discharge pipe itself, and is formed by using a heat-resistant resin. The off-gas discharge pipe 410 is provided with a pressure regulating valve 420. In FIG. 1, the pressure regulating valve 420 is shown in the middle of the pipeline of the off-gas upstream side discharge pipe 411, but is provided on a manifold jig described later in which the off-gas upstream side discharge pipe 411 is fixed at the upstream end thereof. There is. The pressure regulating valve 420 adjusts the pressure of air in the fuel cell 100.

The liquid water discharge pipe 430 connects the gas-liquid separator 280 and the off-gas discharge pipe 410. The liquid water discharge pipe 430 is connected to the discharge valve 440. In the present embodiment, the discharge valve 440 and the liquid / water discharge pipe 430 are integrated into the gas / liquid separator 280 as a gas / liquid separation unit 280Y. The discharge valve 440 opens and closes the pipeline of the liquid water discharge pipe 430 under the control of a control unit (not shown), and by opening the pipeline by the discharge valve 440, the separated liquid water stored in the gas-liquid separator 280 is discharged. It is discharged to the off-gas upstream side discharge pipe 411 of the off-gas discharge pipe 410 via the pipe 430. Even after the separated liquid water is discharged, the fuel exhaust gas discharged from the fuel cell 100 is discharged from the off gas upstream side discharge pipe of the off gas discharge pipe 410 via the liquid water discharge pipe 430 in a state where the discharge valve 440 is open. It is discharged to 411. The above-mentioned pipe opening of the discharge valve 440 is executed when the nitrogen concentration in the fuel exhaust gas becomes high or the amount of water in the gas-liquid separator 280 becomes high.

The bypass pipe 450 connects the air supply flow path 320 and the off-gas upstream discharge pipe 411 of the off-gas discharge pipe 410 by bypassing the fuel cell 100, and allows air (oxidized gas) to flow without passing through the fuel cell 100. This is a flow path for flowing into the off-gas discharge pipe 410. The bypass pipe 450 is provided with a bypass flow path adjusting valve 455. The bypass flow path adjusting valve 455 adjusts the flow rate of the bypass air, which is the air flowing through the bypass pipe 450, by opening and closing the valve and adjusting the opening degree of the valve. The silencer 470 provided in the off-gas downstream side discharge pipe 412 of the off-gas discharge pipe 410 reduces the exhaust noise of the exhaust gas passing through the off-gas discharge pipe 410.

The cooling circuit 500 includes a refrigerant supply flow path 510, a refrigerant discharge flow path 515, a radiator flow path 520, a water pump 525, a radiator 530, a refrigerant bypass flow path 540, and a three-way valve 545. The refrigerant supply flow path 510 is a flow path for supplying the refrigerant to the fuel cell 100, and a water pump 525 is arranged in the refrigerant supply flow path 510. The refrigerant discharge flow path 515 is a flow path for discharging the refrigerant from the fuel cell 100. A temperature sensor 550 is provided in the refrigerant discharge flow path 515, and measures the temperature of the refrigerant discharged from the fuel cell 100. The temperature measured by the temperature sensor 550 is substantially equal to the temperature inside the fuel cell 100, and is also substantially equal to the temperature of the exhaust gas discharged from the fuel cell 100. The downstream portion of the refrigerant discharge flow path 515 is connected to the radiator flow path 520 and the refrigerant bypass flow path 540 via a three-way valve 545. The radiator flow path 520 is provided with a radiator 530. The radiator 530 is provided with a radiator fan 535. The radiator fan 535 sends wind to the radiator 530 to promote heat dissipation from the radiator 530. The downstream portion of the radiator flow path 520 and the downstream portion of the refrigerant bypass flow path 540 are connected to the refrigerant supply flow path 510. The refrigerant supply flow path 510 and the refrigerant discharge flow path 515 are connected to the intercooler 340.

FIG. 3 is an explanatory diagram showing the equipment positional relationship of the pipe arrangement region 411E of the off-gas upstream discharge pipe 411 in FIG. 1 in a three-dimensional schematic manner. FIG. 4 is an explanatory diagram showing an outline of the pipeline configuration of the off-gas upstream discharge pipe 411 in a cross-sectional view along the pipeline. In FIG. 3, the main purpose is to show the positional relationship of the peripheral devices of the off-gas upstream discharge pipe 411, and the outer shapes of the individual devices are shown in a schematic manner. Further, FIG. 4 shows the state of the pipeline connection to the off-gas upstream discharge pipe 411 and the transition of the pipeline wall thickness of the off-gas upstream discharge pipe 411.

As shown in FIG. 3, the off-gas upstream discharge pipe 411 includes pipe connecting bodies 411a and 411b whose diameters are expanded at the upper and lower ends of the pipe, bypass pipe connecting body 411c approximately in the middle of the pipe, and bypass pipe connecting body 411c. A branch pipe 411d is provided on the downstream side of the flow path. An air off-gas discharge manifold 102, which is a fixed device on the side of the fuel cell 100, is inserted into the pipe connection body 411a, and an off-gas downstream side discharge pipe 412 (see FIG. 1), which is a fixed device, is inserted into the pipe connection body 411b. Will be inserted. The off-gas discharge manifold 102 corresponds to the oxide gas discharge manifold in the present invention. The off-gas upstream side discharge pipe 411 is liquidtightly and airtightly fixed to the off-gas discharge manifold 102 and the off-gas downstream side discharge pipe 412 at the lower end of the pipeline by a pipe binding band (not shown). The off-gas upstream side discharge pipe 411 is a pipe extending from the uppermost stream of the pipeline connected to the off-gas discharge manifold 102 to the battery peripheral pipeline area connected to the periphery of the fuel battery 100, and is made of rubber as described above. It is a flexible tube that can be bent. Therefore, the off-gas upstream side discharge pipe 411 is incorporated and mounted without any trouble between the off-gas discharge manifold 102, which is the fixing target of the pipe connecting bodies 411a and 411b at the lower end of the pipeline, and the off-gas downstream side discharge pipe 412.

The bypass pipe connection body 411c is a branch pipe body protruding from the middle of the pipeline of the off-gas upstream discharge pipe 411 in the form of a flexible pipe, and the angle θ formed with the air flow direction F indicated by the arrow in the figure is an acute angle. It is said that. A bypass pipe 450 is inserted into the bypass pipe connection body 411c, and the off-gas upstream discharge pipe 411 is liquid-tightly and airtightly fixed to the bypass pipe 450 by the bypass pipe connection body 411c by a pipe binding band (not shown). The bypass pipe 450 fixed in this way is connected to the off-gas upstream side discharge pipe 411 at an acute angle toward the downstream in the flow direction of the air flowing through the off-gas upstream side discharge pipe 411.

As shown in FIGS. 3 and 4, the off-gas upstream discharge pipe 411 has a thick pipe area 411f on the downstream side of the bypass pipe connection body 411c. This thick pipe area 411f is a pipe including a bypass pipe projection portion 411p in which the bypass pipe 450 connected to the bypass pipe connection body 411c is projected onto the inner wall of the off-gas upstream discharge pipe 411 along the center line C thereof. It is the pipeline area of the pipeline on the downstream side of this projection site. The thickness of the thick pipe area 411f is made larger than the thickness of the pipe upstream of the bypass pipe projection portion 411p. In the present embodiment, the wall thickness of the pipe upstream from the bypass pipe projection portion 411p is 3.5 mm, which is the same as the existing off-gas upstream discharge pipe, and the pipe wall thickness of the thick pipe area 411f is 5.0 mm. did. In this case, the degree of thickening in the thick-walled pipeline area 411f is the length of the off-gas upstream discharge pipe 411, the pipeline diameter of the discharge pipe itself, the connection position of the bypass pipe 450, or the off-gas upstream discharge pipe 411 and the bypass pipe. It can be variously specified according to the pipeline diameter ratio of 450, the maximum assumed flow rate of air flowing from the bypass pipe 450 to the off-gas upstream discharge pipe 411, and the like. For example, when the pipe wall thickness on the upstream side of the bypass pipe projection portion 411p is 1.5 to 3.5 mm, the pipe wall thickness of the thick pipe line area 411f is thicker than the pipe wall thickness on the upstream side. The thickness of the meat can be about 3.0 to 6.0 mm, and in this case, the pipe length, the pipe diameter, and the like may be taken into consideration as described above. Then, in the thick-walled pipeline area 411f specified for the thick-walled pipe, if it can be flexed, there is no problem in connecting / fixing to the fixing member at the pipe connecting bodies 411a and 411b at the upper and lower ends of the pipeline.

In addition, the off-gas upstream discharge pipe 411 is provided with a rib 411e for reinforcing the pipe in the pipe area on the side of the pipe connection 411b and the pipe area in which the branch pipe 411d is branched, in addition to the above-mentioned connection body. .. The branch pipe 411d is formed so as to project toward the gas-liquid separator 280 arranged on the side of the off-gas upstream discharge pipe 411, and the liquid water discharge pipe 430 is inserted and connected. After connecting the liquid water discharge pipe 430, the branch pipe 411d is fixed to the liquid water discharge pipe 430 in a liquidtight and airtight manner by a pipe binding band (not shown). In the liquid water discharge pipe 430 connected to the branch pipe 411d in this way, the separated liquid water separated by the gas-liquid separator 280 is discharged through the branch pipe 411d by the discharge valve 440 (see FIG. 1), and the off-gas discharge pipe 410, Specifically, it is discharged to the off-gas upstream discharge pipe 411.

As described above, in the vehicle 20 of the present embodiment equipped with the fuel cell system 10, the off-gas upstream side discharge pipe 411 constituting the off-gas discharge pipe 410 on the side of the fuel cell 100 is provided with the off-gas discharge manifold 102 of the fuel cell 100. The form is a flexible tube that can be bent in the pipeline area from the fuel cell to the vicinity of the fuel cell. Thereby, according to the vehicle 20 of the present embodiment, it is possible to secure the degree of freedom of piping of the off-gas upstream side discharge pipe 411 around the fuel cell and the simplification of the piping work.

In addition to this, in the vehicle 20 of the present embodiment, when air flows from the air supply flow path 320 through the bypass pipe 450 to the off gas upstream side discharge pipe 411 of the off gas discharge pipe 410 with the operation of the fuel cell 100, this air As shown in FIG. 4, flows at a sharp angle toward the downstream of the gas flow direction F flowing through the off-gas upstream discharge pipe 411, and collides with the pipe line including the bypass pipe projection portion 411p at the protrusion of the bypass pipe connection body 411c. do. Impact noise may be generated due to this air collision, but the pipeline area including the bypass pipe projection portion 411p and the pipeline downstream of the bypass pipe projection portion 411p is the pipe upstream of the bypass pipe projection portion 411p. It is a thick pipe area 411f in which the pipe wall thickness is larger than that of the road. Therefore, according to the vehicle 20 of the present embodiment, it is possible to prevent the leakage of the impact sound from the thick-walled pipeline area 411f of the off-gas upstream discharge pipe 411 through which the air merged from the bypass pipe 450 flows to the outside of the discharge pipe. Further, in the vehicle 20 of the present embodiment, the air flows into the off-gas upstream side discharge pipe 411 via the bypass pipe 450 at a sharp angle toward the downstream side of the gas flow direction F flowing through the off-gas upstream side discharge pipe 411. The impact sound itself can be reduced to some extent, and the airflow sound when air flows downstream from the bypass tube projection portion 411p can also be reduced. As a result, according to the vehicle 20 of the present embodiment, it is possible to make it difficult for the vehicle driver and passengers to recognize the sound generated in the off-gas discharge pipe 410 due to the air supply to the fuel cell 100 as noise.

FIG. 5 is a graph showing the measurement result of the generated sound in the off-gas upstream discharge pipe 411. This sound measurement was performed in the following situations. First, the off-gas upstream side discharge of the comparative example product having a uniform pipe wall thickness of 3.5 mm from the pipe connection body 411a on the connection side to the off-gas discharge manifold 102 shown in FIG. A vehicle incorporating the pipe 411 and an embodiment having a pipe wall thickness of 3.5 mm from the pipe connection body 411a to the bypass pipe projection portion 411p and a pipe wall thickness of 5.0 mm in the thick pipe area 411f. A vehicle incorporating the off-gas upstream discharge pipe 411 was prepared. Then, the operation of each vehicle is set to the end state, and the specified amount of air at the time of stopping the operation is sent out to the air supply flow path 320 by the air compressor 330 without causing the fuel cell 100 to generate electricity. Of the sent out air, air having a flow rate required for scavenging the air flow path in the fuel cell 100 flows through the fuel cell 100 and then is discharged to the off-gas upstream side discharge pipe 411. At the same time, excess air exceeding the amount required for scavenging flows into the off-gas upstream discharge pipe 411 via the bypass pipe 450. In this situation, the sound collecting microphone was set in the mounting area 40 in front of the passenger compartment 30 shown in FIG. 2, and the sound leaking from the off-gas upstream side discharge pipe 411 was incorporated into the off-gas upstream side discharge pipe 411 of the comparative example product. The measurement was performed individually in the vehicle and the vehicle incorporating the off-gas upstream discharge pipe 411 of the embodiment.

As shown in FIG. 5, the sound having a frequency exceeding 700 Hz was measured at a volume exceeding 70 dB in all the vehicles, but in the vehicle incorporating the off-gas upstream discharge pipe 411 of the embodiment, the off-gas upstream discharge pipe is used. A decrease in the volume of the sound leaking from 411 was observed. For this reason as well, according to the vehicle 20 of the present embodiment incorporating the off-gas upstream side discharge pipe 411 of the embodiment, the noise generated in the off-gas discharge pipe 410 due to the air supply to the fuel cell 100 is heard in the vehicle operation. It can be said that it can be made difficult for people and passengers to recognize it as noise.

In the vehicle 20 of the present embodiment, the fuel cell 100 is mounted in the mounting area 40 on the front side of the vehicle from the vehicle compartment 30, so that the sound generated in the off-gas discharge pipe 410 due to the air supply to the fuel cell 100 is in the vehicle compartment. It is easily perceived by 30 vehicle drivers and passengers. However, as described above, since the sound generated in the off-gas discharge pipe 410 can be hardly recognized as noise, it is possible to make it difficult for the vehicle driver and passengers to feel a sense of discomfort when the vehicle is started or stopped.

The present invention is not limited to the above-described embodiment, and can be realized with various configurations within a range not deviating from the gist thereof. For example, the technical features in the embodiments corresponding to the technical features in each embodiment described in the column of the outline of the invention are for solving a part or all of the above-mentioned problems, or one of the above-mentioned effects. It is possible to replace or combine as appropriate to achieve the part or all. Further, if the technical feature is not described as essential in the present specification, it can be appropriately deleted.

In the vehicle 20 of the present embodiment, the fuel cell 100 is mounted in the mounting area 40 on the front side of the vehicle from the vehicle interior 30, but the present invention is not limited to this. For example, due to the structure of the vehicle body, even if the fuel cell 100 is mounted in the lower region of the vehicle compartment 30 or on the rear side of the vehicle compartment 30, the sound generated in the off-gas discharge pipe 410 can be hardly recognized as noise.

In the vehicle 20 of the present embodiment, in the fuel cell system 10, the bypass pipe connecting body 411c is provided substantially in the middle of the pipe line of the off-gas discharge pipe 410, but the pipe connecting body upstream area or the pipe connecting body 411b on the side of the pipe connecting body 411a is provided. It may be provided in the downstream area of the pipeline on the side of. Further, the branch pipe 411d may be provided on the upstream side of the bypass pipe connection body 411c.

10 ... Fuel cell system, 20 ... Vehicle, 30 ... Vehicle room, 40 ... Mounting area, 100 ... Fuel cell, 102 ... Off gas discharge manifold, 200 ... Fuel gas supply circuit, 210 ... Fuel gas tank, 220 ... Fuel gas supply flow path , 230 ... Fuel gas exhaust flow path, 240 ... Fuel gas circulation flow path, 250 ... Main valve, 260 ... Regulator, 270 ... Injector, 280 ... Gas-liquid separator, 280Y ... Gas-liquid separation unit, 290 ... Recirculation pump, 300 ... air supply circuit, 310 ... air cleaner, 320 ... air supply flow path, 330 ... air compressor, 340 ... intercooler, 350 ... stack inlet valve, 375 ... atmospheric pressure sensor, 380 ... outside temperature sensor, 385 ... air flow meter, 390 ... Supply gas temperature sensor, 395 ... Supply gas pressure sensor, 400 ... Exhaust gas circuit, 410 ... Off gas discharge pipe, 411 ... Off gas upstream side discharge pipe, 411E ... Pipe arrangement area, 411a ... Pipe connection body, 411b ... Pipe connection body, 411c ... Bypass pipe connection body, 411d ... Branch pipe, 411e ... Rib, 411f ... Thick-walled pipe area, 411p ... Bypass pipe projection site, 412 ... Off-gas downstream discharge pipe, 420 ... Pressure control valve, 430 ... Liquid water discharge Pipe, 440 ... Discharge valve, 450 ... Bypass pipe, 455 ... Bypass flow path adjustment valve, 470 ... Silencer, 500 ... Cooling circuit, 510 ... Fuel supply flow path, 515 ... Fuel discharge flow path, 520 ... Radiator flow path, 525 ... Water pump, 530 ... Radiator, 535 ... Radiator fan, 540 ... Fuel bypass flow path, 545 ... Three-way valve, 550 ... Temperature sensor, C ... Center line

Claims (1)

It ’s a fuel cell vehicle,
Oxidation gas supply flow path that supplies oxidation gas to the fuel cell,
An oxidation gas discharge pipe connected to the oxidation gas discharge manifold of the fuel cell and guiding the oxidation gas discharged from the fuel cell to the outside,
A bypass pipe for connecting the oxidation gas supply flow path and the oxidation gas discharge pipe by bypassing the fuel cell is provided.
The oxidative gas discharge pipe has a flexible pipe form from the uppermost stream of the pipeline connected to the oxidative gas discharge manifold to the battery peripheral pipeline area piped around the fuel cell.
Further, the oxide gas discharge pipe is connected to a bypass pipe in which the bypass pipe is connected at a sharp angle toward the downstream in the flow direction of the oxide gas flowing through the oxide gas discharge pipe in the middle of the flexible pipe form. A pipe line including a bypass pipe projection portion and the bypass pipe in which the body is projected and the bypass pipe connected to the bypass pipe connection body is projected onto the inner wall of the oxide gas discharge pipe along the center line of the bypass pipe. A fuel cell vehicle in which the pipeline on the downstream side of the projection portion is a conduit having a thickness larger than that on the upstream side of the bypass pipe projection portion.

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