JP6272726B2 - Vehicle exhaust structure - Google Patents

Description

  The present invention relates to an exhaust structure for a vehicle equipped with an exhaust pipe for exhausting.

  In general, in vehicles equipped with an engine that exhausts exhaust using hydrogen or petroleum-based fuel, or vehicles equipped with a power source such as a fuel cell that exhausts exhaust gas, the power source such as a power source or fuel cell is connected to the front part of the vehicle body. And a diluter for diluting exhaust gas at the rear of the vehicle body (see, for example, Patent Document 1).

  In a general vehicle such as a fuel cell vehicle described in Patent Document 1, a radiator with a fan is disposed at the front end of the vehicle body, a fuel cell or an engine cooled by the radiator is disposed behind the radiator, and the fuel cell is disposed at the rear of the vehicle body. And a diluter for diluting the exhaust discharged from the engine. Exhaust gas discharged from the fuel cell or engine is sent to the rear part of the vehicle body by an exhaust pipe disposed in the under floor space of the vehicle body, and then discharged to the rear of the vehicle body. The exhaust gas flowing in the exhaust pipe contains generated water generated during the power generation of the fuel cell and other impurities.

JP 2009-170209 A

FIG. 7 is a schematic view showing a comparative example of an exhaust pipe mounted on a fuel cell vehicle.
As shown in FIG. 7, in the exhaust pipe 200 of the comparative example mounted on the fuel cell vehicle 100, the front end portion 210 is connected to the fuel cell 300 disposed in the front portion of the vehicle body, and the rear end portion 220 is connected to the rear portion of the vehicle body. It arrange | positions in the state opened toward the vehicle rear side through the diluter 400 arrange | positioned.

  The front end portion 210 of the exhaust pipe 200 extends toward the rear of the vehicle body from below the motor room MR, below the partition wall 500, and below the cross member and the front subframe extending in the vehicle width direction. For this reason, the front end portion 210 of the exhaust pipe 200 is formed with a run-down portion 230 that obliquely descends rearward in the vicinity of the under-floor front end portion 110 of the vehicle.

  The rear end portion 220 of the exhaust pipe 200 passes through the lower side of the cross member and the rear subframe extending in the vehicle width direction from the rear end portion of the underfloor space 120 of the passenger compartment, and is disposed in the underfloor space 130 of the cargo compartment. It extends toward. When the fuel cell vehicle 100 moves backward and collides with the curbstone 600, the diluter 400 has a height H100 of the curbstone 600 to prevent the function from being deteriorated due to deformation or damage due to the collision load. It is arrange | positioned in the position of height H200 higher than this. For this reason, the rear end portion 220 of the exhaust pipe 200 is formed with a run-up portion 240 that rises obliquely in the rearward direction in the vicinity of the front of the under-floor space 130 of the vehicle.

  In the exhaust pipe 200 mounted on the fuel cell vehicle 100 shown in FIG. 7, the run-down portion 230 and the run-up portion 240 are formed, so that the lower end portions of the run-down portion 230 and the run-up portion 240 are formed. It is low. For this reason, when the generated water flows through the exhaust pipe 200, the generated water stays at the lower ends of the run-down portion 230 and the run-up portion 240, and the drainage performance cannot be said to be good.

  When the generated water stays in the exhaust pipe 200, the generated water freezes when the outside air is in a low temperature state such as in the severe winter season, and depending on the situation, the flow path in the exhaust pipe 200 is blocked and the exhaust is discharged. There was a fear that it was not. Further, in cold regions, when snow adheres to the diluter 400 at the rear end of the exhaust pipe 200, the moisture in the exhaust pipe 200 and the diluter 400 is frozen by the snow and the outside air temperature, and the exhaust pipe 200 is frozen. The volume of the inside and the diluter 400 may be reduced, so that the performance of the diluter 400 may be deteriorated.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an exhaust structure for a vehicle that can discharge water remaining in an exhaust pipe.

As a means for solving the above problem, an exhaust structure for a vehicle according to the present invention, through the exhaust from the previous person, up unit ran formed toward upward, or formed toward downward An exhaust pipe having a run-down portion, an air blowing means used in a vehicle equipped with the exhaust pipe, and any position between the upstream of the exhaust pipe and the run-up portion or the run-down portion And an introduction pipe for introducing gas from the blowing means , wherein the blowing means is a compressor, and the introduction pipe sends compressed air generated by the compressor to the upstream side of the exhaust pipe. A first introduction pipe that is introduced, and a second introduction pipe that introduces compressed air that has been pressurized by the compressor and heated to a high temperature and cooled by an intercooler, to the upstream side of the exhaust pipe. under Or the compressed air introduced from the compressor into the exhaust pipe through the first introduction pipe or the second introduction pipe, and It is characterized by being discharged .

According to such a configuration, the exhaust structure of the vehicle is generated by the gas from the blower means being introduced into the exhaust pipe via the introduction pipe, and staying in the run-up portion or the run-down portion of the exhaust pipe. Water such as water can be blown out of the exhaust pipe by the introduced gas.
Further, according to such a configuration, since the air blowing means is a compressor, the air that has been pressurized by the compressor and heated to a high temperature is introduced into the exhaust pipe, so that the water that has been frozen in the exhaust pipe is thawed. Can be blown off. For this reason, even if water is frozen in the exhaust pipe, the water frozen by the hot air from the compressor can be thawed and vaporized, so that the exhaust pipe can be prevented from being blocked by freezing.

During addition, the exhaust pipe is arranged to extend toward the rear of the vehicle body from the vehicle body front portion of the motor room through the underfloor space, said came under rising portion until underfloor front end of the vehicle from the front end portion of the exhaust pipe disposed position, the bet on rising portion is preferably disposed in the rear portion of the vehicle body.

According to such a configuration, the exhaust pipe introduces the compressed air (gas) from the blowing means (compressor) to the upstream side of the down part of the exhaust pipe via the introduction pipe, or In addition, moisture such as generated water staying in the run-down portion can be discharged out of the exhaust pipe by the introduced gas.

Moreover, it is preferable to provide the diluter into which the said exhaust_gas | exhaustion sent by the said exhaust pipe is sent in the rear-end part side of the said exhaust pipe .

According to such a configuration, the exhaust pipe is provided with the diluter on the rear end side, so that the gas from the blowing means can be sent to the diluter and the water remaining in the diluter can be blown off. it can.

  Moreover, it is preferable that the said ventilation means supplies oxygen containing gas with respect to a fuel cell.

  According to such a configuration, the air blowing means can generate power by supplying oxygen-containing gas to the fuel cell so that oxygen in the oxygen-containing gas undergoes an electrochemical reaction with hydrogen in the fuel cell, and surplus. The remaining water can be discharged out of the exhaust pipe by using the flow of the oxygen-containing gas supplied to.

  Moreover, it is preferable that the said ventilation means supplies the gas for cooling with respect to an electrical storage apparatus.

  According to such a configuration, the air blowing unit can cool the power storage device with the cooling gas by supplying the cooling gas to the power storage device, and can use the cooled gas that has been heated, It is possible to accelerate the thawing of frozen water or to discharge the accumulated water out of the exhaust pipe.

  Moreover, it is preferable that a ventilation means is arrange | positioned at the motor room of the said vehicle, and supplies the external air attracted | sucked and taken in from the vehicle body front.

  According to such a configuration, the blowing means arranged in the motor room introduces the outside air sucked and taken in from the front of the vehicle body into the exhaust pipe, and thereby vaporizes the generated water stored in the exhaust pipe by the outside air. Can be discharged.

  Further, any position between the upstream side of the exhaust pipe and the run-up part or the run-down part is, among the exhaust pipes, when the vehicle is most inclined in the terrain where the vehicle can travel. It is preferable to set it to the lowest part.

  According to such a configuration, in the exhaust pipe, water tends to accumulate in the lowest set portion between the run-up portion or the run-down portion. Even if water accumulates in the lowest set part, the gas sent from the blower means is sent to the lowest set part from the upstream of the exhaust pipe to vaporize and discharge water or frozen water Can do.

  The exhaust structure of a vehicle according to the present invention can vaporize and drain moisture remaining in the exhaust pipe or frozen moisture.

It is a schematic diagram showing an example of a vehicle carrying an exhaust structure for a vehicle according to an embodiment of the present invention. It is a block diagram which shows an example of the exhaust structure of the vehicle which concerns on embodiment of this invention. It is a schematic perspective view of the rear part of the vehicle body showing the installation state of the exhaust pipe. It is the schematic which shows a state when the vehicle carrying the exhaust structure of the vehicle which concerns on embodiment of this invention climbs a slope. It is the schematic which shows a state when the vehicle carrying the exhaust structure of the vehicle which concerns on embodiment of this invention goes down a slope. It is the schematic which shows another example of the vehicle carrying the exhaust structure of the vehicle which concerns on embodiment of this invention. It is the schematic which shows the comparative example of the exhaust pipe mounted in a fuel cell vehicle.

With reference to FIGS. 1-5, the exhaust structure of the vehicle which concerns on embodiment of this invention is demonstrated.
It is assumed that the forward direction of the vehicle is “front”, the backward direction is “rear”, the vertical upper side is “up”, the vertical lower side is “lower”, and the vehicle width direction is “left” and “right”.

≪Vehicle≫
First, before describing a vehicle exhaust structure according to an embodiment of the present invention, a vehicle C to which the vehicle exhaust structure of the present invention is applied will be described. As shown in FIG. 1, the vehicle C is equipped with an exhaust pipe 6 for sending exhaust exhausted from a device using fuel toward the vehicle body rear portion 8 b, and a blowing means 3 for introducing gas into the exhaust pipe 6. If it is an automobile, its type and type are not particularly limited. That is, the vehicle C only needs to have the exhaust pipe 6 and the air blowing means 3.
Further, if the vehicle C travels with an engine that discharges exhaust gas using hydrogen or petroleum-based fuel or alternative fuel, a power unit that is driven by power from a power source that discharges exhaust gas, etc., The format and type are not particularly limited. That is, the vehicle C may be a passenger car, a bus, a truck, a work vehicle, or the like.
Hereinafter, as an example of the vehicle C, an embodiment of the present invention will be described by taking a passenger car type fuel cell vehicle V equipped with a fuel cell 10 that discharges hydrogen off-gas as an example.

≪Configuration of fuel cell vehicle≫
As shown in FIG. 1, the fuel cell vehicle V is an electric vehicle that travels by rotating a traveling motor (not shown) for traveling by the generated power of the fuel cell 10, and is mounted with the fuel cell system 1. The fuel cell vehicle V (vehicle C) has a fuel cell 10 that generates power using hydrogen in front of the vehicle body rear portion 8b. In the vehicle body front portion 8a of the fuel cell vehicle V, a motor room MR in which the radiator 2, the fuel cell 10, a travel motor (not shown), the compressor 31 (air blowing means 3), and the like are housed is installed. A hydrogen tank 4 and a diluter 5 are provided in the vehicle body rear portion 8 b of the fuel cell vehicle V. An exhaust pipe 6 is installed from the vehicle body front portion 8a to the vehicle body rear portion 8b. Further, the exhaust pipe 6 and the exhaust silencer 11 are disposed in the underfloor space 85 of the passenger compartment.

As shown in FIG. 1, a partition wall 8d that forms a rear inner wall of the motor room MR is provided on the rear side of the vehicle body of the motor room MR.
The radiator 2 sucks and takes in the traveling wind generated by the traveling of the fuel cell vehicle V from the front of the vehicle body and cools the cooling water as the heat medium. The radiator 2 includes, for example, a radiator with a fan that cools the cooling water for cooling the fuel cell 10 and the traveling motor (not shown) with air.

  The travel motor (not shown) is an electric motor that rotates using the electric power generated by the fuel cell 10 to drive the wheels. In addition, the current supplied to the travel motor (not shown) is adjusted by an inverter (not shown) or a power drive unit (PDU).

  The exhaust silencer 11 is a device that has a predetermined internal space whose diameter has been expanded, and suppresses noise generated by exhaust of the fuel cell 10 sent through the exhaust pipe 6.

≪Fuel cell system≫
As shown in FIG. 2, the fuel cell system 1 includes a fuel cell 10, an anode system that supplies and discharges hydrogen (fuel gas, reactive gas) to and from the anode of the fuel cell 10, and a cathode of the fuel cell 10. A cathode system that supplies and discharges oxygen-containing air (oxidant gas, reaction gas), a power control system that controls the power generation of the fuel cell 10, and an electronic control device (not shown) that electronically controls them. Yes.

≪Fuel cell≫
The fuel cell 10 is configured to generate power by an electrochemical reaction between hydrogen and oxygen by supplying hydrogen to the anode electrode and supplying air (oxygen) as an oxidant gas to the cathode electrode. In the fuel cell 10, when power is generated, water is generated by an electrochemical reaction between hydrogen gas and oxidant gas. The generated product water stays in the hydrogen off-gas circulation path 43.

<Anode system>
The anode system includes a hydrogen tank 4 (fuel gas supply source), a heat exchanger 41, a pressure sensor P1, a shutoff valve V1, an ejector 42, a catch tank 44, a circulation pump 45, and a check valve 46. , Orifices 47 and 49, a purge valve V2, a water level sensor 48, and a drain valve V3.

  The hydrogen tank 4 is a container filled with high-purity hydrogen gas, which is fuel supplied to the fuel cell 10. A hydrogen gas supply path 40 for sending hydrogen gas to the fuel cell 10 is connected to the hydrogen tank 4. The hydrogen tank 4 is disposed horizontally in front of the cargo compartment 84 near the rear wheel of the fuel cell vehicle V (see FIG. 1).

  The hydrogen gas supply path 40 is a flow path for sending high-pressure hydrogen in the hydrogen tank 4 to the fuel cell 10. The hydrogen gas supply path 40 has an upstream side connected to the hydrogen tank 4 and a downstream side connected to the fuel cell 10 via a heat exchanger 41, a pressure sensor P 1, a shut-off valve V 1, and an ejector 42. A hydrogen off-gas circulation path 43 in which a circulation pump 45 for circulating hydrogen off-gas is arranged is connected between the shutoff valve V1 of the hydrogen gas supply path 40 and the ejector 42.

The heat exchanger 41 exchanges heat with the outside of the hydrogen gas, which has expanded when the hydrogen gas is discharged from the hydrogen tank 4 and the temperature has decreased, and absorbs external heat to raise the temperature. It is an apparatus that adjusts to a temperature at which it is easy to humidify by preventing the gas dew point temperature from decreasing.
The shutoff valve V <b> 1 is a valve that is opened by a command from an electronic control device (not shown) and supplies hydrogen gas to the fuel cell 10.
The pressure sensor P <b> 1 is a measuring instrument that measures the pressure of hydrogen gas that flows through the hydrogen gas supply path 40 and is supplied to the fuel cell 10. The pressure sensor P1 is interposed between the heat exchanger 41 and the shutoff valve V1.
The ejector 42 includes a nozzle (not shown) that generates a negative pressure by injecting hydrogen gas from the shutoff valve V1, and a hydrogen off-gas and nozzle from the orifice 47 (hydrogen off-gas circulation path 43) sucked by the negative pressure. And a diffuser (not shown) that mixes and supplies the hydrogen gas injected from the fuel gas 10 toward the fuel cell 10.

  The hydrogen off gas circulation path 43 is a flow path for circulating the hydrogen off gas discharged from the fuel cell 10 back to the hydrogen gas supply path 40 again. The hydrogen off-gas circulation path 43 is provided with a catch tank 44, a circulation pump 45, a check valve 46, and an orifice 47. Further, in the hydrogen off-gas circulation path 43, a drain path 71 provided with a catch tank 44, an orifice 49 and a drain valve V3, and a hydrogen off-gas discharge path 72 branched from the hydrogen off-gas circulation path 43 and provided with a purge valve V2. And are connected.

The catch tank 44 is a tank that stores generated water generated by the power generation of the fuel cell 10. The catch tank 44 is provided with a water level sensor 48 that detects the amount of generated water stored.
The orifice 49 is for adjusting the flow rate of the hydrogen off gas containing the generated water discharged from the catch tank 44.
The drain valve V3 is an electromagnetic valve for draining water (condensation water) stored in the catch tank 44 from the drainage channel 71 by opening the valve.

  The circulation pump 45 is a pump for circulating the hydrogen off gas in the hydrogen off gas circulation path 43 connected in the middle of the hydrogen gas supply path 40. The circulation pump 45 has an upstream side connected to the catch tank 44 and a downstream side connected to the ejector 42 via a check valve 46.

The check valve 46 is a valve that restricts the flow of the hydrogen off-gas flowing through the hydrogen off-gas circulation path 43 in one direction (downstream direction) and prevents it from flowing in the reverse direction.
The orifice 47 is for regulating and adjusting the flow rate of the hydrogen off gas flowing from the hydrogen off gas circulation path 43 to the ejector 42, and is connected in parallel to the check valve 46. The orifice 47 has an upstream side connected to the circulation pump 45 and a downstream side connected to the ejector 42.

  When the purge valve V2 is operated by a command from an electronic control unit (not shown) during power generation of the fuel cell 10, the purge valve V2 contains impurities (water vapor, nitrogen, etc.) contained in the hydrogen off-gas circulating in the hydrogen off-gas circulation path 43. ) Is discharged to the hydrogen off-gas discharge path 72.

  The drainage channel 71 is a pipe for sending the generated water stored in the catch tank 44 to the exhaust pipe 6. The drainage channel 71 has an upstream side connected to the catch tank 44 via a drain valve V3 and an orifice 49, and a downstream side connected to a branch point d with the exhaust pipe 6 (oxygen offgas discharge channel).

  The hydrogen off gas discharge path 72 is a pipe for sending hydrogen off gas to the exhaust pipe 6. The upstream side of the hydrogen off-gas discharge path 72 is connected between the catch tank 44 and the circulation pump 45 of the hydrogen off-gas circulation path 43 via the purge valve V2, and the downstream side is a branch point e with the exhaust pipe 6 (see FIG. 1). It is connected to the.

<Cathode system>
The cathode system includes an air cleaner Ac, a flow meter Q1, a first temperature sensor T1, a compressor 31 (air blowing means 3), a silencer 32, an intercooler 33, a pressure sensor P2, and a first sealing valve V4. The humidifier 34 is mainly provided.

As shown in FIG. 2, the air cleaner Ac is a filter that removes dust when the air is sucked into the air supply channel 30, and is provided at the upstream end of the air supply channel 30. The downstream side of the air cleaner Ac is connected to the compressor 31 via the flow meter Q1 and the first temperature sensor T1.
The flow meter Q1 is a measuring instrument that measures the flow rate of the air taken into the air supply flow path 30, and outputs the detected flow rate to an electronic control device (not shown).
The first temperature sensor T1 is a measuring instrument that measures the temperature of the atmosphere introduced into the air supply flow path 30, and outputs the detected temperature to an electronic control device (not shown).

<Blower unit>
The blower means 3 is a blower source for introducing compressed air (gas) into the exhaust pipe 6 through an introduction pipe 60 described later. The blower 3 is also a blower source that supplies air to the fuel cell 10 via the air supply passage 30. That is, the air blowing means 3 is used in the vehicle C on which the exhaust pipe 6 is mounted. An introduction pipe 60 is connected to the downstream side of the blowing means 3. The air blowing means 3 is composed of a compressor 31, for example.

  The compressor 31 (air blowing means 3) is a device that drives the air pump 31a by the rotation of the motor 31b and generates high-temperature compressed air by the compressor 31c. The compressor 31 is used to send out air supplied as an oxidant to the fuel cell 10. When the compressor 31 operates in response to a command from an electronic control device (not shown), it supplies air containing oxygen (oxidant gas) to the exhaust pipe 6 via the fuel cell 10 or an introduction pipe 60 described later. ing.

  The air supply channel 30 is a supply channel that supplies air to the cathode of the fuel cell 10. The air supply flow path 30 is connected to the flow meter Q1, the first temperature sensor T1, and the air cleaner Ac via the compressor 31 on the upstream side, and the silencer 32, the intercooler 33, the pressure sensor P2, and the first sealing valve V4 on the downstream side. And the fuel cell 10 through the humidifier 34. In the middle of the air supply flow path 30, a first introduction pipe 61 (introduction pipe 60) provided with a first control valve V5 and a second introduction pipe 62 (introduction pipe 60) provided with a second control valve V6 are provided. ) And an oxygen off-gas circulation path 35 provided with an exhaust gas recirculation pump 36 and a check valve 37.

  The silencer 32 is a device that reduces noise generated by high-pressure air flowing through the air supply flow path 30. The silencer 32 has an upstream side connected to the compressor 31 c and a downstream side connected to the intercooler 33.

  The intercooler 33 is a device that cools air that has been heated by being compressed by the compressor 31. The intercooler 33 includes, for example, an air-cooling type and a water-cooling type, but either may be used. The intercooler 33 has an upstream side connected to the first introduction pipe 61 and a downstream side connected to the humidifier 34 via the pressure sensor P2 and the first sealing valve V4.

The pressure sensor P2 detects the pressure of the air supply flow path 30 between the intercooler 33 and the first sealing valve V4, and outputs the pressure to an electronic control device (not shown).
The first sealing valve V4 is, for example, an electromagnetically operated on-off valve, and the downstream side is connected to the cathode flow path of the fuel cell 10 via the humidifier 34. The first sealing valve V4 is provided between the pressure sensor P2 of the air supply passage 30 and the humidifier 34, and fulfills the function of shutting off the air supply side of the fuel cell 10 in the closed state.

The humidifier 34 incorporates a hollow fiber membrane through which moisture can permeate. By this hollow fiber membrane, between the air toward the cathode channel of the fuel cell 10 and the humid oxygen off-gas discharged from the fuel cell 10. Moisture exchange is performed to humidify new air toward the fuel cell 10.
The second temperature sensor T <b> 2 is a measuring instrument that measures the temperature of the oxygen off gas discharged from the fuel cell 10 to the exhaust pipe 6, and is provided in the exhaust pipe 6 between the fuel cell 10 and the humidifier 34. The second temperature sensor T2 outputs the detected temperature to an electronic control device (not shown).

<Introduction pipe>
The introduction pipe 60 is a pipe for introducing the gas from the compressor 31 (the air blowing means 3) into the exhaust pipe 6. The introduction pipe 60 has an upstream side connected to the air supply passage 30 communicating with the compressor 31 and a downstream side connected to the upstream side of the run-down portion 6 c of the exhaust pipe 6. The introduction pipe 60 includes a first introduction pipe 61 and a second introduction pipe 62, and is disposed in the motor room MR (see FIG. 1).

  The first introduction pipe 61 is a flow path for introducing the compressed air generated by the compressor 31 to the upstream side of the run-down portion 6 c of the exhaust pipe 6, and constitutes a first bypass flow path that bypasses the fuel cell 10. ing. The first introduction pipe 61 has an upstream side connected to the air supply flow path 30 between the silencer 32 and the intercooler 33, and a downstream side branched from the branch point d between the exhaust pipe 6 and the hydrogen offgas discharge path 72. Connected to point c. When the first control valve V5 of the first introduction pipe 61 is opened by a command of an electronic control device (not shown), the air pressurized by the compressor 31 and heated to the first temperature is supplied from the air supply flow path 30 to the first control valve V5. 1 is an electromagnetic valve for sending upstream of the run-down portion 6c of the exhaust pipe 6 through the introduction pipe 61.

  As shown in FIG. 2, the second introduction pipe 62 is a flow path for introducing the compressed air of the compressor 31 upstream of the run-down portion 6 c of the exhaust pipe 6, and a second bypass flow that bypasses the fuel cell 10. Constitutes the road. Similar to the first control valve V5, the second control valve V6 of the second introduction pipe 62 is heated by the compressor 31 and cooled by the intercooler 33 when opened by a command from an electronic control unit (not shown). This is an electromagnetic valve for sending the air that has been discharged from the air supply flow path 30 to the upstream of the run-down portion 6 c of the exhaust pipe 6 through the second introduction pipe 62.

  As shown in FIG. 1, the new compressed air that has been pressurized by the compressor 31 to a high temperature passes through the air supply flow path 30 through the first introduction pipe 61 or the second introduction pipe 62 and enters the exhaust pipe 6. It is sent to the diluter 5 through the run-down portion 6c and the run-up portion 6d (see FIG. 3).

  The oxygen off-gas circulation path 35 is a flow path for circulating the oxygen off-gas discharged from the fuel cell 10 to the exhaust pipe 6 by returning it to the air supply flow path 30 via the second temperature sensor T2 and the humidifier 34. The oxygen off-gas circulation path 35 is provided with an exhaust gas recirculation pump 36 and a check valve 37.

The exhaust gas recirculation pump 36 is a pump for causing the oxygen off gas to flow, the upstream side is connected to the humidifier 34 on the exhaust pipe 6 side, and the downstream side is a humidifier on the air supply flow path 30 side via a check valve 37. 34.
The check valve 37 is a valve that regulates the direction of oxygen off gas flowing through the oxygen off gas circulation path 35 so as to flow in one direction from the exhaust pipe 6 side to the air supply flow path 30 side.

<Exhaust pipe>
The exhaust pipe 6 is an oxygen off gas discharge path for sending the oxygen off gas discharged from the fuel cell 10 to the diluter 5. The exhaust pipe 6 has an upstream front end 6a connected to the fuel cell 10 disposed in the motor room MR, and a downstream rear end 6b connected to the diluter 5 disposed in the vehicle body rear portion 8b. In the middle of the exhaust pipe 6, the second temperature sensor T2, the humidifier 34, the second sealing valve V7, and the back pressure valve V8 are provided.

  As shown in FIG. 1, the front side of the exhaust pipe 6 passes through the lower side of the partition wall 8 d from the branch point e of the motor room MR, the lower side of the cross member and the front subframe extending in the vehicle width direction, and the underfloor space 85. Extending toward the rear of the vehicle body. For this reason, the exhaust pipe 6 is formed with a run-down portion 6c that descends obliquely rearward at a position between the front end portion 6a and the vicinity of the under-floor front end portion 8c of the vehicle C.

  As shown in FIG. 3, the rear side of the exhaust pipe 6 passes through the floor panel 81, the body frame 82, and the rear subframe 83 below the floor in front of the vehicle body and loads the cargo in the cargo compartment 84 (see FIG. 1). It extends to the diluter 5 arranged in the under-chamber space 86. A diluter 5 is provided at the rear end 6 b on the downstream side of the exhaust pipe 6.

  As shown in FIG. 1, when the fuel cell vehicle V moves backward and collides with the curbstone 9, the diluter 5 is used to prevent the function from being deteriorated due to deformation or damage due to the collision load. It is arranged at a position higher than the curb 9. For this reason, on the front side of the rear end portion 6b of the exhaust pipe 6, a run-up portion 6d that rises obliquely upward toward the rear side is formed.

  As described above, the exhaust pipe 6 includes the run-down portion 6c formed downward and the run-up portion 6d formed upward. The exhaust pipe 6 is connected to the introduction pipe 60 (the first introduction pipe 61 and the second introduction pipe 62) at a position upstream from the position of the run-down portion 6c. For this reason, the exhaust pipe 6 has the first introduction pipe 61 such that the gas (compressed air) heated by the compression heat from the compressor 31 (air blowing means 3) is introduced from the upstream side of the run-down portion 6c. It is connected. The exhaust pipe 6 is connected to the second introduction pipe 62 so that the gas (compressed air) cooled by the intercooler 33 is introduced from the upstream side of the run-down portion 6c.

  As shown in FIG. 2, the second sealing valve V <b> 7 is an electromagnetically operated on / off valve, for example, and is connected to the cathode flow path of the fuel cell 10 via the humidifier 34. The second sealing valve V7 and the back pressure valve V8, which will be described later, are provided between, for example, a branch point a between the exhaust pipe 6 and the oxygen off-gas circulation path 35 and a branch point b between the exhaust pipe 6 and the second introduction pipe 62. It is connected to the. The second sealing valve V7 functions to close the downstream side of the branch point a of the exhaust pipe 6 in the closed state. When the second sealing valve V7 is closed, the oxygen off gas that has passed through the humidifier 34 on the exhaust pipe 6 side passes through the exhaust gas recirculation pump 36 and the check valve 37 to the air supply flow path 30 side. It flows to the humidifier 34.

  The back pressure valve V8 is constituted by, for example, a butterfly valve. The back pressure (exhaust pipe 6) is controlled by controlling the opening degree of the back pressure valve V8 in accordance with a command from an electronic control unit (not shown).

<Diluter>
As shown in FIG. 2, the diluter 5 joins the hydrogen off-gas (hydrogen) discharged through the purge valve V2 and the drain valve V3 with the oxygen off-gas discharged from the fuel cell 10 through the exhaust pipe 6. It is a device that further dilutes and discharges the air by sucking and mixing the atmosphere into the exhaust flow. The diluter 5 includes a rear end 6b of the exhaust pipe 6 for ejecting a mixed flow of hydrogen off-gas and oxygen off-gas sent through the exhaust pipe 6, and an outer diameter larger than that of the rear end 6b. A housing 51 that is formed with a gap (suction port) with the portion 6b, and that can suck the ambient air from the suction port using negative pressure due to the flow of exhaust from the rear end 6b. I have. By mixing the exhaust and the sucked air in the casing 51, the diluted exhaust 5 is set to a predetermined hydrogen concentration or less in the diluter 5, and then the atmosphere is discharged from the exhaust port at the rear end of the casing 51. Discharged inside. The exhaust port of the housing 51 is formed obliquely downward toward the rear of the vehicle, and exhaust is discharged downward downward.

  In addition, the shape and form of the diluter 5 are not particularly limited. A diluter may be provided by installing a dilution box 50 in which hydrogen off-gas and oxygen off-gas are reliably mixed at a position indicated by a broken line in FIG.

≪Operation of vehicle exhaust structure≫
Next, the operation of the exhaust structure for a vehicle according to the present embodiment will be described with reference to FIGS.
First, when the driver turns on an ignition switch (not shown) of the fuel cell vehicle V, the compressor 31 shown in FIG. 2 is driven. The hydrogen in the hydrogen tank 4 is supplied to the anode electrode of the fuel cell 10 through the hydrogen gas supply path 40, and the air humidified by the humidifier 34 from the compressor 31 through the air supply path 30 is used as fuel. It is supplied to the cathode electrode of the battery 10. As a result, hydrogen and oxygen in the humidified air are generated in the fuel cell 10 by an electrochemical reaction, and electric power (generated current) is supplied to a load such as a travel motor (not shown) to rotate the travel motor. The driving wheels of the fuel cell vehicle V are driven by the power.

  Further, in order to increase the utilization efficiency of hydrogen, hydrogen discharged from the anode electrode of the fuel cell 10 is introduced into the anode electrode of the fuel cell 10 via the hydrogen off-gas circulation path 43 and recirculated. Further, the hydrogen off gas discharged through the purge valve V <b> 2 during the hydrogen purge process is introduced into the diluter 5 through the hydrogen off gas discharge path 72 and the exhaust pipe 6.

  Compressed air (oxygen-containing gas) pressurized by the compressor 31 (air blowing means 3) is sent to the fuel cell 10 and then becomes oxygen off-gas and merges with hydrogen off-gas upstream of the exhaust pipe 6, and then It is introduced into the downstream diluter 5. In the diluter 5, the atmosphere is sucked into and mixed with the exhaust flow, and the hydrogen in the exhaust flow is further diluted. Exhaust gas discharged from the casing 51 of the diluter 5 is discharged into the atmosphere in a state where the hydrogen concentration is less than a predetermined value.

  When the first control valve V5 of the first introduction pipe 61 shown in FIG. 2 is opened, the compressed air that has been pressurized by the compressor 31 and heated to the first introduction pipe 61 from the air supply flow path 30. And is introduced upstream of the run-down portion 6 c of the exhaust pipe 6. For this reason, a part of the compressed air having a high oxygen concentration at a high temperature generated by the compressor 31 (the air blowing means 3) does not pass through the fuel cell 10 and runs down the exhaust pipe 6 through the first introduction pipe 61. 6c and run-up portion 6d. The compressed air can be discharged from the exhaust pipe 6 by thawing and vaporizing the generated water stored in the run-down section 6 c and the run-up section 6 d in the exhaust pipe 6 or the frozen generated water.

Further, the compressed air having a high oxygen concentration at a high temperature enters the diluter 5 and thaws and vaporizes the generated water stored in the diluter 5 or the frozen generated water from the diluter 5 to the atmosphere. Can be discharged inside.
For this reason, the exhaust pipe 6 is closed in a severe winter season or in a cold region, the generated water in the exhaust pipe 6 freezes and becomes blocked, or the generated water in the diluter 5 freezes and the volume of the diluter 5 decreases. By doing so, it is possible to solve the problem that the hydrogen off-gas becomes difficult to flow and the dilution performance deteriorates.

  In addition, when the second control valve V6 of the second introduction pipe 62 is opened, compressed air that has been heated by the compressor 31 and cooled by the intercooler 33 is supplied to the exhaust pipe 6 through the air supply passage. 30 to the upstream of the run-down portion 6 c of the exhaust pipe 6 through the second introduction pipe 62. For this reason, since the compressed air cooled by the intercooler 33 flows through the run-down portion 6c and the run-up portion 6d of the exhaust pipe 6 through the first introduction pipe 61, the generated water stored in the exhaust pipe 6 Can be blown off downstream with compressed air and discharged into the atmosphere via the diluter 5.

  As shown in FIG. 4, when the vehicle C climbs up a hill and the vehicle C is in the most inclined state on the terrain where the vehicle C can travel, the vehicle body front portion 8 a side of the vehicle C becomes higher and the vehicle body rear portion 8 b The side is in a low state. For this reason, when such a vehicle C is tilted backward, in the exhaust pipe 6, the lower end portion 6f of the run-up portion 6d on the vehicle body rear portion 8b side is at the lowest position, and the generated water runs up the run-up portion 6d. It is set so as to be easily stored in the lower end 6f.

  As shown in FIG. 5, when the vehicle C goes down a hill and the vehicle C is in the most inclined state on the terrain where the vehicle C can travel, the vehicle body front portion 8a side of the vehicle C becomes lower and the vehicle body rear portion 8b. The side becomes high. For this reason, when the vehicle C is tilted forward, in the exhaust pipe 6, the lower end portion 6e of the run-down portion 6c on the vehicle body front portion 8a side is at the lowest position, and the generated water runs down the run-down portion 6d. Is set so as to be easily stored in the lower end portion 6e.

  As described above, when the first control valve V5 is opened, the compressed air from the compressor 31 is introduced into the exhaust pipe 6 as compressed air heated at the compressor 31 from the first introduction pipe 61, When the second control valve V6 is opened, the compressed air cooled by the intercooler 33 from the second introduction pipe 62 is introduced into the exhaust pipe 6 respectively.

  For this reason, as shown in FIGS. 4 and 5, when the vehicle C is in the rearward tilted state and the rearwardly forward tilted state, the generated water is stored in the lower end portion 6c and the lower end portions 6e and 6f of the uphill portion 6d. Even if it is frozen, the generated water can be vaporized and discharged by compressed air that has been heated to high temperature or compressed air that has been dried before being humidified.

  The opening of the first control valve V5 and the second control valve V6 may be automatically opened and closed when the vehicle C is parked or driven, or may be manually opened and closed with a switch. It may be. Further, the first control valve V5 and the second control valve V6 do not need to be used when the generated water is not accumulated in the exhaust pipe 6 and the diluter 5.

  Thus, the vehicle exhaust structure according to the present invention introduces compressed air (gas) from the blowing means 3 (compressor 31) to the upstream side of the run-down portion 6c of the exhaust pipe 6 through the introduction pipe 60. Then, moisture such as generated water staying in the run-up portion 6d or the run-down portion 6c can be discharged out of the exhaust pipe 6 by the introduced gas. For this reason, the oxygen off-gas etc. discharged from the fuel cell 10 to the exhaust pipe 6 can always be maintained in a state where it easily flows in the exhaust pipe 6 toward the diluter 5.

≪Modification≫
The present invention is not limited to the above-described embodiment, and various modifications and changes can be made within the scope of the technical idea. The present invention extends to these modifications and changes. Of course.

For example, the first introduction pipe 61 and the second introduction pipe 62 shown in FIG. 1 and FIG. 3 are connected to a position between the run-up portion 6d upstream of the exhaust pipe 6 and the run-down portion 6c. You may make it introduce | transduce the gas (compressed air) heated by the compression heat from (the ventilation means 3) from the upstream of the run-up part 6d.
That is, the first introduction pipe 61 and the second introduction pipe 62 are connected to the run-down portion 6c of the exhaust pipe 6 or the upstream side of the run-up portion 6d and are stored in at least the rear run-up portion 6d. The generated water may be discharged by compressed air.

  Further, as shown in FIG. 6, the blower 3 may be a blower source (fan) that supplies a cooling gas to the power storage device 91 set in the underfloor space 85 of the passenger compartment. The power storage device 91 is a device for accumulating electricity generated by the fuel cell 10, and is composed of, for example, a battery or a capacitor. Examples of the battery include a lead storage battery, a lithium ion secondary battery, a lithium polymer secondary battery, a nickel metal hydride storage battery, and a nickel cadmium storage battery. Examples of the capacitor include an electric double layer capacitor and an electrolytic capacitor.

In this case, the piping 3a through which the cooling gas is sent from the blower 3 to the power storage device 91 is set. The pipe 3a includes a cooling unit 3b for cooling the power storage device 91, a discharge port 3c from which the gas deprived of heat of the power storage device 91 is discharged, and a discharge pipe 3d extending from the discharge port 3c toward the rear of the vehicle body. , Is provided. The discharge pipe 3d has a pipe 3e (introduction pipe 60) connected to the upstream side of the run-down portion 6c (or the run-up portion 6d) of the exhaust pipe 6 and provided with an on-off valve (not shown). And further connected.
In this way, in the exhaust pipe 6, the cooling gas that has become hot air by heat exchange by cooling the power storage device 91 with the cooling gas from the blowing means 3 opens the on-off valve (not shown). Thus, since the water is fed into the exhaust pipe 6 through the discharge pipe 3d and the pipe 3e, the generated water stored in the run-up portion 6d can be surely discharged, and the thawing of the frozen water can be accelerated. it can.
Further, the pipe 3e may be connected on the upstream side to the pipe 3a and on the downstream side between the run-up portion 6d of the exhaust pipe 6 and the exhaust silencer 11.

Further, the blower unit 3 may be a blower source that is disposed in the motor room MR of the vehicle C and supplies outside air sucked and taken in from the front of the vehicle body.
In this case, the air blowing means 3 includes, for example, a fan (the air blowing means 3) of the radiator 2 with a fan disposed in the motor room MR of the vehicle C. In the blowing means 3, the sucked outside air flows into the exhaust pipe 6 so that the outside air sucked and taken in from the front of the vehicle body is introduced to the run-down portion 6 c of the exhaust pipe 6 or upstream of the run-up section 6 d. For this purpose, an outside air introduction pipe (introduction pipe 60) is provided. An exhaust pipe 6 is connected to the downstream end of the outside air introduction pipe (introduction pipe 60).
Thus, even if the wind generated by the fan (air blowing means 3) is sent to the upstream portion in the exhaust pipe 6, the generated water stored in the exhaust pipe 6 can be discharged.

DESCRIPTION OF SYMBOLS 3 Blowing means 5 Diluter 6 Exhaust pipe 6d Run-up part 6c Run-down part 8a Car body front part 8b Car body rear part 11 Exhaust silencer 31 Compressor 60 Introduction pipe 61 1st introduction pipe 61 (introduction pipe)
62 Second introduction pipe 62 (introduction pipe)
91 Power storage device C Vehicle FC Fuel cell MR Motor room V Fuel cell vehicle

Claims (7)

Through an exhaust from the previous person, up unit ran formed toward upward, or, an exhaust pipe having a ran down portion formed toward downward,
Air blowing means used in a vehicle equipped with the exhaust pipe;
From the upstream of the exhaust pipe, connected to any position between the run-up part or the run-down part, and an introduction pipe for introducing the gas from the blowing means ,
The air blowing means is a compressor,
The introduction pipe includes a first introduction pipe that introduces compressed air generated by the compressor to an upstream side of the exhaust pipe;
A second introduction pipe that introduces compressed air that has been pressurized by the compressor and heated to an intercooler to the upstream side of the exhaust pipe,
Compressed air in which moisture accumulated at the lower end of the run-up portion or the lower end of the run-down portion is introduced from the compressor into the exhaust pipe through the first introduction pipe or the second introduction pipe An exhaust structure for a vehicle, wherein the exhaust structure is discharged outside the exhaust pipe . The exhaust pipe extends from the motor room at the front of the vehicle body through the space under the floor toward the rear of the vehicle body,
Wherein ran under rising portion is disposed at a position between the front end portion of the exhaust pipe to the floor front portion of the vehicle,
Exhaust structure for a vehicle according to claim 1 wherein ran on rising portion, characterized in that disposed in the rear portion of the vehicle body. The exhaust structure for a vehicle according to claim 1 or 2 , further comprising a diluter on the rear end side of the exhaust pipe into which the exhaust sent by the exhaust pipe is sent.   The exhaust structure for a vehicle according to any one of claims 1 to 3, wherein the blowing means supplies an oxygen-containing gas to the fuel cell.   The exhaust structure for a vehicle according to claim 1, wherein the blowing unit supplies a cooling gas to the power storage device.   The exhaust structure for a vehicle according to claim 1 or 2, wherein the blower means is arranged in a motor room of the vehicle and supplies outside air sucked and taken in from the front of the vehicle body.   Any position between the upstream side of the exhaust pipe and the run-up part or the run-down part is the lowest of the exhaust pipes when the vehicle leans forward most in the terrain where the vehicle can travel. The exhaust structure for a vehicle according to any one of claims 1 to 6, wherein the exhaust structure is set in a portion.

Images