CN114852348A

CN114852348A - Multi-rotor aircraft

Info

Publication number: CN114852348A
Application number: CN202111638799.3A
Authority: CN
Inventors: 関根広之
Original assignee: Toyota Motor Corp
Current assignee: Toyota Motor Corp
Priority date: 2021-02-03
Filing date: 2021-12-29
Publication date: 2022-08-05
Also published as: JP7472813B2; JP2022118987A

Abstract

The present disclosure provides a multi-rotor aircraft. The multi-rotor aircraft disclosed in the present specification is provided with a fuel cell, a propeller, a housing, and a first release port. The fuel cell reacts fuel gas to generate electric power. The propeller is rotated by electric power generated by the fuel cell. The housing houses the fuel cell and has at least one ventilation port. The first release port releases the exhaust gas of the fuel gas discharged from the fuel cell into the housing. In the multi-rotor aircraft described above, the exhaust gas is released into the housing that houses the fuel cell. The exhaust gas is diffused and diluted in the housing. The inside of the casing is ventilated through the ventilation port.

Description

Multi-rotor aircraft

Technical Field

The technology disclosed herein relates to a multi-rotor aircraft. And more particularly to a multi-rotor aircraft having propellers and a fuel cell that generates electric power for rotating the propellers.

Background

The above-described multi-rotor aircraft (referred to as an aircraft in japanese patent laid-open No. 2018-176920) is disclosed in japanese patent laid-open No. 2018-176920. The fuel cell reacts oxygen and fuel gas to generate electric power. The fuel cell discharges, as an exhaust gas, excess fuel that has flowed into the fuel cell but is not consumed and remains. The exhaust gas discharged from the fuel cell is discharged to the outside from the discharge port through the fuel discharge pipe. The exhaust gas discharge port is disposed below the propeller, and is configured to promote discharge of exhaust gas by wind generated when the propeller rotates.

Disclosure of Invention

The exhaust gas discharged from the fuel cell contains fuel gas. Therefore, when the exhaust gas is released to the outside, it is desirable to dilute the exhaust gas and release the diluted exhaust gas so as to reduce the concentration of the fuel gas. In this regard, in the multi-rotor aircraft according to japanese patent laid-open publication No. 2018-176920, since the exhaust gas discharge port is disposed below the propeller, it is expected that the exhaust gas is diluted by the wind generated by the propeller. However, the number of revolutions of the propeller may be reduced, for example, at the time of takeoff or landing of the multi-rotor aircraft. At such a time, since the amount of air generated by the propeller decreases, the exhaust gas discharged from the fuel cell may not be sufficiently diluted. In this case, there is a possibility that the concentration of the fuel gas may rise around the exhaust port of the multi-rotor aircraft. In the present specification, a technology capable of diluting exhaust gas and discharging the diluted exhaust gas to the outside is provided.

The multi-rotor aircraft disclosed in the present specification is provided with a fuel cell, a propeller, a housing, and a first release port. The fuel cell reacts fuel gas to generate electric power. A propeller is rotated by the electric power generated by the fuel cell. A housing receives the fuel cell and has at least one vent. The first release port releases the exhaust gas of the fuel gas discharged from the fuel cell into the housing.

In the multi-rotor aircraft, the exhaust gas discharged from the fuel cell is discharged into the housing that houses the fuel cell. The exhaust gas released into the housing is diffused in the housing and diluted, and then released from the ventilation port of the housing to the outside. In this way, in the multi-rotor aircraft disclosed in the present specification, the exhaust gas is diffused in the housing that houses the fuel cell, and the exhaust gas can be diluted and discharged to the outside.

Details and further modifications of the technology disclosed in the present specification will be described in the following "detailed description of the preferred embodiments".

Drawings

The features, advantages, technical and industrial significance of the representative embodiments of the present invention will be described with reference to the following drawings, in which like numerals represent like elements, and in which:

fig. 1 shows a perspective view of an embodiment of a multi-rotor aircraft 10.

Fig. 2 shows a top view of the embodiment of multi-rotor aircraft 10.

Fig. 3 shows a cross-sectional view at the line III-III of fig. 2.

Fig. 4 shows a cross-sectional view of the second embodiment of multi-rotor aircraft 10a taken along line IV-IV of fig. 1.

Detailed Description

In one embodiment of the present technology, the at least one transfer port may include an opening provided at a position facing a rotation range of the propeller. This allows ventilation of the inside of the housing by the wind generated by the propeller. As a result, dilution of the exhaust gas can be promoted.

In one embodiment of the present technology, the multi-rotor aircraft may further include a second release port that releases exhaust gas of air discharged from the fuel cell into the housing. Thereby, the exhaust gas of the air discharged from the fuel cell and the exhaust gas of the fuel gas are mixed in the casing. As a result, dilution of the exhaust gas can be promoted.

In one embodiment of the present technology, the fuel cell system may further include a compressor that is housed in the case and supplies air to the fuel cell. According to such a structure, since the size of the housing becomes large, the exhaust gas released into the housing is released to the outside of the housing after being sufficiently diffused to be diluted. However, in other embodiments, the housing may not house the compressor.

In one embodiment of the present technology, the multi-rotor aircraft may further include a radiator that cools the fuel cell. In this case, the heat sink may be adjacent to the housing in a direction orthogonal to a rotation axis of the propeller. However, in another embodiment, the heat sink may be adjacent to the housing in the rotation axis direction of the propeller.

(embodiment mode)

A multi-rotor aircraft 10 as one embodiment of the present technology will be described with reference to the drawings. As shown in fig. 1, multi-rotor aircraft 10 includes four propellers 8, fuel gas tank 2, radiator 6, radiator fan 6f, and power unit 4. Although not particularly limited, the multi-rotor aircraft 10 is a so-called drone, and can fly by rotationally driving the four propellers 8. Multi-rotor aircraft 10 is raised in the Z-axis direction (i.e., the direction above the paper in fig. 1). After ascent, multi-rotor aircraft 10 performs parallel movement, turning, and the like by setting a difference to the respective numbers of revolutions of four propellers 8.

The fuel gas tank 2 stores fuel gas (hydrogen gas in the present embodiment) therein. The power unit 4 houses a fuel cell 4b and an air compressor 4a inside a casing 4c thereof. The fuel cell 4b includes a stack (not shown) therein, and generates electric power by reacting fuel gas with oxygen in the air. The air compressor 4a is a device for supplying air to the fuel cell 4 b. In addition, a secondary battery or the like that stores electric power generated by the fuel cell 4b is housed in the case 4 c.

The multi-rotor aircraft 10 generates electric power by reacting fuel gas in the fuel gas tank 2 with oxygen in the air in the fuel cell 4 b. The multi-rotor aircraft 10 rotates the four propellers 8 by supplying electric power generated by the fuel cell 4b to an electric motor (not shown).

The housing 4c of the power unit 4 has a rectangular shape extending in the X-axis direction (i.e., the left-right direction of the paper surface in fig. 1). A base for fixing the fuel gas tank 2 is provided at an upper portion of the housing 4c, and propeller support portions 8s are provided at four corners of the base, respectively. Each propeller support portion 8s rotatably supports the propeller 8.

A heat sink 6 and a heat sink fan 6f are disposed on the X-axis direction positive side (i.e., the left side of the sheet of fig. 1) of the housing 4 c. A circulation passage through which a refrigerant circulates is formed inside the radiator 6. The heat sink 6 is provided with a circulation passage extending in the Z-axis direction so as to be adjacent to each other in the Y-axis direction. Although not shown, a circulation passage for supplying the refrigerant to the fuel cell 4b is connected to the radiator 6. The housing 4c houses a pump that circulates a refrigerant between the radiator 6 and the fuel cell 4 b.

As shown in fig. 1, the radiator 6 is exposed to the X-axis direction positive side of the power unit 4. When multi-rotor aircraft 10 travels, for example, to the X-axis direction positive side, radiator 6 receives a wind of flight toward the X-axis direction negative side (i.e., the right side of the paper in fig. 1). When the flying wind passes through the radiator 6, the heat of the refrigerant in the radiator 6 is radiated. In addition, the heat of the refrigerant in the radiator 6 is radiated by the air flow in various directions passing through the radiator 6. The radiator fan 6f is disposed on a surface of the flat radiator 6 on the X-axis direction negative side (i.e., on the right side of the paper surface in fig. 1) so as to be in contact with the surface. When the multi-rotor aircraft 10 is not traveling, the radiator fan 6f rotates to radiate the heat of the refrigerant in the radiator 6. In this way, the multi-rotor aircraft 10 cools the fuel cell 4b by supplying the fuel cell 4b with the refrigerant that has been radiated by the radiator 6.

As shown in fig. 2, each of the four propellers 8 rotates about a propeller center 8 c. Each of the four propellers 8 rotates so as to cover a circular rotation range 8a centered on a propeller center 8 c. When the propeller 8 rotates, wind is generated below the rotation range 8a (i.e., in the depth direction of the paper surface in fig. 2).

An air supply port 4s is provided on the upper side (i.e., the front side of the paper surface in fig. 2) of the casing 4 c. The air supply port 4s is located below the rotation range 8a of the propeller 8 on the X-axis direction negative side (i.e., the right side in the drawing sheet of fig. 2) and on the Y-axis direction negative side (i.e., the upper side in the drawing sheet of fig. 2).

Here, a configuration for discharging the exhaust gas of the fuel gas to the outside of the multi-rotor aircraft 10 according to the present embodiment will be described with reference to fig. 3. The fuel cell 4b is connected to a gas-liquid separator 14. The gas-liquid separator 14 is supplied with the fuel gas (i.e., the off gas of the fuel gas) that has passed through the fuel cell 4 b. The gas-liquid separator 14 separates moisture in the off gas of the fuel gas from the fuel side off gas G1. A gas/water discharge valve 14v is connected at the bottom of the gas-liquid separator 14, and when the gas/water discharge valve 14v is opened, moisture separated from the off gas of the fuel gas and retained at the bottom of the gas-liquid separator 14 will be discharged. The fuel side offgas G1 separated from the moisture by the gas-liquid separator 14 is released from the first release port 14h in the upper portion of the gas-liquid separator 14 into the space 4m inside the housing 4 c.

Here, the fuel side off gas G1 is a fuel gas (i.e., hydrogen gas) that has passed through the fuel cell 4 b. The fuel side exhaust gas G1 contains fuel gas in addition to the impurities (e.g., nitrogen and water vapor) after the reaction. Therefore, it is required for the multi-rotor aircraft 10 to dilute the fuel side exhaust gas G1 to reduce the concentration of the fuel gas before discharging the fuel side exhaust gas G1 to the outside. The multi-rotor aircraft 10 is discharged from the first discharge port 14h to the space 4m in the casing 4c before discharging the fuel-side exhaust gas G1 to the outside. Thereby, the fuel side exhaust gas G1 diffuses in the space 4m and mixes with the air in the space 4 m. As a result, the concentration of the fuel gas in the space 4m decreases. That is, the fuel side exhaust gas G1 is diluted by being released into the space 4 m.

An exhaust port 4e is provided in a wall of the lower side (i.e., the Z-axis direction negative side) of the housing 4 c. The exhaust port 4e penetrates a wall on the lower side of the housing 4c to communicate the space 4m inside the housing 4c with the outside. The fuel side exhaust gas G1 diluted in the space 4m is discharged to the outside as dilution exhaust gas G2 through the exhaust port 4 e. The space 4m of the casing 4c is ventilated by providing the casing 4c with an exhaust port 4 e. That is, the exhaust port 4e is a ventilation port for ventilating the inside of the casing 4 c.

In this way, the multi-rotor aircraft 10 of the present embodiment discharges the fuel-side exhaust gas G1 into the space 4m of the casing 4c, dilutes the exhaust gas in the space 4m, and then discharges the diluted exhaust gas to the outside through the exhaust port 4 e. This enables the fuel side exhaust gas G1 to be diluted and discharged to the outside by the casing 4 c. As described above, the housing 4c is a housing for housing the fuel cell 4b, the air compressor 4a, and other devices. By diluting the fuel side exhaust gas G1 with the casing 4c, it is not necessary to provide a device for diluting the fuel side exhaust gas G1. Therefore, the multi-rotor aircraft 10 can dilute the fuel side exhaust gas G1 and discharge it to the outside with a relatively simple configuration.

Further, since the housing 4c houses the fuel cell 4b, the air compressor 4a, and other devices, the volume of the space 4m inside thereof becomes large. Dilution of the fuel side exhaust gas G1 can be promoted by diluting the fuel side exhaust gas G1 in the case 4c having a large internal volume.

An air supply port 4s is provided in a wall on the upper side (i.e., the positive side in the Z-axis direction) of the housing 4 c. As described above, the air supply port 4s is located below the rotation range 8a of the propeller 8. That is, the air supply port 4s faces the rotation range 8 a. When the propeller 8 rotates, a downward wind is generated below the rotation range 8 a. As shown in fig. 3. A part of the wind generated by the rotation of the propeller 8 pushes air S1 into the space 4m of the casing 4c through the air supply port 4S. Thereby, the air in the space 4m circulates, and the space 4m is ventilated. Thus, the air supply port 4s is a ventilation port for ventilating the inside of the casing 4 c. The air supply port 4s is disposed below the rotation range 8a of the propeller 8 to ventilate the space 4m, thereby promoting dilution of the fuel side exhaust gas G1.

A multi-rotor aircraft 10a according to a second embodiment will be described with reference to fig. 4. The multi-rotor aircraft 10a according to the second embodiment includes a second release port 20h instead of the air intake port 4s (see fig. 3) of the multi-rotor aircraft 10 according to the first embodiment described above. The second release port 20h is an opening provided on the air release pipe 20 of the fuel cell 4 b. The second release port 20h communicates the space 4m of the housing 4c with the air release pipe 20. The air release pipe 20 is a pipe for discharging the air having passed through the fuel cell 4b from the fuel cell 4b (i.e., the air-side off-gas S2). The air-side off-gas S2 discharged from the fuel cell 4b is discharged into the space 4m of the casing 4c via the second discharge port 20h of the air discharge pipe 20. The exhaust gas S2 of the air released from the second release port 20h is mixed with the fuel side exhaust gas G1 released from the first release port 14h in the space 4 m. As a result, dilution of the concentration of the fuel side exhaust gas G1 is promoted. In this way, the multi-rotor aircraft 10a according to the second embodiment dilutes the fuel side exhaust gas G1 with the exhaust gas of the air discharged from the fuel cell 4b itself, instead of the air taken into the space 4m from the air inlet 4 s. This makes it possible to dilute the fuel side exhaust gas G1 and discharge it to the outside with a relatively simple configuration without adding a separate configuration.

Although the embodiments have been described in detail above, these are merely examples and do not limit the patent claims. The technology described in the patent claims includes various modifications and changes to the specific examples illustrated above. Hereinafter, modifications of the above embodiment will be described.

Although the exhaust port 4e and the air supply port 4s are provided in the housing 4c as "ventilation ports" in the first embodiment described above, in a modified example, the "ventilation ports" may be gaps generated between the structural members of the housing 4c instead of the above-described structure. That is, even if an explicit "ventilation port" is not provided, the space 4m may be communicated with the outside at a part of the housing 4 c. In a further modification, the housing 4c may be provided with an air supply port 4s, and the second release port 20h may be provided in the housing 4 c.

(modification 2) in the above-described embodiment, the multi-rotor aircraft 10 includes four propellers 8, but the multi-rotor aircraft 10 of the modification may include two or three propellers 8, or may include five or more propellers 8.

(modification 3) in the first embodiment described above, the air supply port 4s faces the rotation range 8a of the propeller 8 from below, but in a modification, a ventilation port facing the rotation range 8a of the propeller 8 from above may be provided instead of the air supply port 4 s. In this case, the vicinity of the rotation range 8a becomes negative pressure by the rotation of the propeller 8, and therefore the air in the space 4m is easily discharged to the outside. That is, the transfer ports facing the rotation range 8a of the propeller 8 from above function as exhaust ports.

(modification 4) in the above-described embodiment, the air compressor 4a is housed in the casing 4c, but in the modification, the air compressor 4a may be disposed outside the casing 4 c. Further, the fuel gas tank 2 may be further disposed in the casing 4 c.

(modification 5) in the above-described embodiment, the radiator 6 is disposed adjacent to the housing 4c in the X-axis direction, but in the modification, the radiator 6 and the power unit 4 may be disposed adjacent to each other in the Z-axis direction or may be disposed adjacent to each other in the Y-axis direction.

Although specific examples of the present invention have been described in detail above, these are merely examples and do not limit the technical scope of the patent. The technology described in the claims includes various modifications and changes to the specific examples illustrated above. The technical elements described in the present specification or the drawings are elements that exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of application. Further, the techniques illustrated in the present specification or the drawings can achieve a plurality of objects at the same time, and achieving one of the objects itself has technical usefulness.

Claims

1. A multi-rotor aircraft is provided with:

a fuel cell that reacts fuel gas to generate electric power;

a propeller that is rotated by the electric power generated by the fuel cell;

a housing that houses the fuel cell and has at least one ventilation port;

a first discharge port that discharges an off-gas of the fuel gas discharged from the fuel cell into the housing.

2. The multi-rotor aerial vehicle of claim 1,

the at least one transfer port includes an opening disposed at a position opposite a rotational range of the propeller.

3. The multi-rotor aerial vehicle of claim 1 or 2,

the fuel cell system further includes a second release port that releases an exhaust gas of air discharged from the fuel cell into the housing.

4. The multi-rotor aerial vehicle of any one of claims 1-3,

the fuel cell system further includes a compressor housed in the housing and configured to supply air to the fuel cell.

5. The multi-rotor aerial vehicle of any one of claims 1 through 4,

further comprising a radiator for cooling the fuel cell,

the heat sink abuts the housing in a direction orthogonal to the rotational axis of the propeller.