Multirotor aircraft

Abstract

The present invention provides a multi-rotor aircraft. The multi-rotor aircraft includes a propeller, a power unit, and a radiator. The power unit rotates the propeller. The radiator is exposed to the outside and cools the power unit. The center of gravity of the multi-rotor aircraft is located inside the radiator. The above-mentioned multi-rotor aircraft is constructed so that the center of gravity of the entire multi-rotor aircraft is located in an area where the radiator is located, which is prone to resistance during flight. Therefore, the distance between the part that is subjected to resistance during flight and the center of gravity of the multi-rotor aircraft is short. As a result, even if the radiator is subjected to resistance during flight, the moment with the center of gravity of the multi-rotor aircraft as the fulcrum will become smaller.

Description

Technical Field

[0001] The technology disclosed in this specification relates to a multi-rotor aircraft, and more particularly to a multi-rotor aircraft with a radiator. Background Art

[0002] Japanese Patent Application Laid-Open No. 2018-176920 discloses a multi-rotor aircraft equipped with a fuel cell. The multi-rotor aircraft cools the fuel cell through a radiator. Summary of the invention

[0003] The radiator has a shape that is easily resistant to wind in order to effectively release the heat recovered from the fuel cell to the outside air. Therefore, in a multi-rotor aircraft having a radiator, wind resistance is likely to act locally on the radiator, and the flight of the multi-rotor aircraft may become unstable. In this specification, a technology that enables stable flight in a multi-rotor aircraft having a radiator exposed to the outside is disclosed.

[0004] The multi-rotor aircraft disclosed in this specification includes a propeller, a power unit and a radiator. The power unit rotates the propeller. The radiator is exposed to the outside and cools the power unit. The center of gravity of the multi-rotor aircraft is located inside the radiator.

[0005] In the above-mentioned multi-rotor aircraft, the center of gravity of the multi-rotor aircraft as a whole is located in the area where the radiator that is easily subjected to wind resistance exists. As a result, the distance between the part where the wind resistance is easily concentrated and the center of gravity of the multi-rotor aircraft will become shorter. As a result, even if the wind resistance acts on the radiator to a large extent, the moment that makes the posture of the multi-rotor aircraft disordered will also become smaller. That is, the multi-rotor aircraft disclosed in this specification can fly stably.

[0006] The details and further improvements of the technology disclosed in this specification will be described in the following “Specific embodiments”. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] Hereinafter, features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will be described with reference to the accompanying drawings, in which like symbols represent like elements, wherein:

[0008] Figure 1 A perspective view showing a multirotor aircraft 10 according to an embodiment.

[0009] Figure 2 A top view of the multirotor aircraft 10 according to the embodiment is shown.

[0010] Figure 3 express Figure 2Cross-sectional view at line III-III. DETAILED DESCRIPTION

[0011] In one embodiment of the present technology, the radiator may be configured to be tilted upward as it moves from one side to the other side in a direction perpendicular to the rotation axis of the propeller. Thus, when the multi-rotor aircraft moves from one side to the other side in a direction perpendicular to the rotation axis of the propeller, lift is generated on the tilted radiator, thereby making the flight of the multi-rotor aircraft more stable.

[0012] In one embodiment of the present technology, the power unit may include a fuel cell. In this case, the radiator may also cool the fuel cell. However, in other embodiments, the power unit may include both a secondary battery and an engine.

[0013] In one embodiment of the present technology, the multi-rotor aircraft may also include a fuel gas tank for storing the fuel gas supplied to the fuel cell. In this case, the fuel gas tank may be arranged directly above the radiator, and the power unit may be arranged directly below the radiator. According to such a structure, when the multi-rotor aircraft lands, it is possible to prevent the fuel gas tank from being damaged.

[0014] In one embodiment of the present technology, the center point of the propeller may be located on a plane passing through the radiator. By aligning the radiator, which is susceptible to resistance during flight, and the center point of the propeller that enables the multi-rotor aircraft to fly on the same plane, the multi-rotor aircraft can fly more stably.

[0015] (Implementation Method)

[0016] Referring to the accompanying drawings, a multi-rotor aircraft 10 as one embodiment of the present technology will be described. Figure 1 As shown, the multi-rotor aircraft 10 includes four propellers 8, a fuel gas tank 2, a tank base 9, a radiator 6, a radiator fan 6f, and a power unit 4. Although not particularly limited, the multi-rotor aircraft 10 is a so-called drone, and can fly by rotating the four propellers 8. The multi-rotor aircraft 10 moves in the Z-axis direction (i.e., Figure 1 After ascending, the multi-rotor aircraft 10 performs parallel movement, turning, etc. by setting differences in the number of revolutions of each of the four propellers 8.

[0017] The fuel gas tank 2 stores fuel gas (hydrogen in this embodiment) therein. The power unit 4 contains a fuel cell 4b and an air compressor 4a inside its housing 4c. The fuel cell 4b has a battery pack (not shown) inside, and generates electricity by reacting the fuel gas with oxygen in the air. The air compressor 4a is a device for supplying air to the fuel cell 4b. In addition, a secondary battery or the like for storing the electricity generated by the fuel cell 4b is contained in the housing 4c.

[0018] The multirotor 10 generates electricity by reacting the fuel gas in the fuel gas tank 2 with oxygen in the air in the fuel cell 4b. The multirotor 10 rotates the four propellers 8 by supplying the electricity generated by the fuel cell 4b to an electric motor (not shown).

[0019] like Figure 1 As shown, the tank base 9 is supported on the housing 4c of the power unit 4 by four columns 9p. The fuel gas tank 2 is arranged on the upper surface of the tank base 9. A propeller support portion 8s is connected to each of the four columns 9p. The propeller support portions 8s extend in directions orthogonal to the columns 9p, respectively, and support the propeller 8 in a rotatable manner.

[0020] The radiator 6 and the radiator fan 6f are arranged above the housing 4c in a manner surrounded by four pillars 9p. A circulation channel for circulating the refrigerant is formed inside the radiator 6. The radiator 6 is arranged so that the circulation channel extending in the Z-axis direction is adjacent to each other in the Y-axis direction. As a result, the radiator 6 is located on the positive side in the X-axis direction (i.e., Figure 1 The radiator 6 is a flat shape having a flat surface 6p (left side of the paper). Although not shown in the figure, a circulation channel for supplying a refrigerant to the fuel cell 4b is connected to the radiator 6. The housing 4c contains a pump for circulating the refrigerant between the radiator 6 and the fuel cell 4b.

[0021] Since the spaces between the four columns 9p are open, the heat sink 6 is exposed to the outside. Figure 1 When the heat sink 6 moves toward the negative side of the X-axis direction (i.e., Figure 1 When the flying wind passes through the radiator 6, the heat of the refrigerant in the radiator 6 is dissipated. In addition, the flying wind in different directions passes through the radiator 6, so that the heat of the refrigerant in the radiator 6 is dissipated. The radiator fan 6f is arranged on the negative side of the X-axis direction of the flat radiator 6 (that is, Figure 1When the multi-rotor aircraft 10 is not moving, the heat of the refrigerant in the radiator 6 is dissipated by rotating the radiator fan 6f. In this way, the multi-rotor aircraft 10 cools the fuel cell 4b by supplying the refrigerant whose heat is dissipated by the radiator 6 to the fuel cell 4b.

[0022] Reference Figure 2 as well as Figure 3 , the configuration of each device of the multi-rotor aircraft 10 is described. The fuel gas tank 2 is arranged along the X-axis direction (ie, Figure 2 The radiator 6 is arranged in a manner perpendicular to the X-axis direction. The power unit 4 is also arranged in a direction along the X-axis direction. The propeller support portion 8s extends from the column 9p in a manner inclined relative to the X-axis direction. The propeller 8 can be rotated with the rotation axis 8a passing through its center point 8c (see Figure 3 ) is supported at the top of the propeller support portion 8s in a manner that the propeller 8 rotates around the center. As a result, the propeller 8 is separated from the column 9p. Thus, even if the propeller 8 rotates, it will not interfere with the column 9p.

[0023] like Figure 2 As shown, the multi-rotor aircraft 10 has a central axis 1x in the width direction and a central axis 1x in the Y-axis direction (ie, Figure 2 Furthermore, the multi-rotor aircraft 10 has a shape that is symmetrical in the X-axis direction (ie, Figure 2 As a result, the center of gravity G1 of the multi-rotor aircraft 10 becomes the intersection of the width direction center axis 1x and the length direction center axis 1y when viewed from above.

[0024] like Figure 3 As shown, in the case of a multi-rotor aircraft 10, Figure 3 When the multi-rotor aircraft 10 is traveling in the direction of the traveling direction F1, a flying wind W1 is generated relative to the multi-rotor aircraft 10. The radiator 6 cools the refrigerant by the flying wind W1 during flight. In order to increase the area contacted by the flying wind W1, the radiator 6 has a flat surface 6p. However, the radiator 6 having the flat surface 6p is easily affected by the flying wind W1. The flying wind W1 received by the flat surface 6p of the radiator 6 generates a large resistance to the multi-rotor aircraft 10 traveling in the traveling direction F1.

[0025] like Figure 3As shown, the fuel gas tank 2 is arranged just above the radiator 6. This can prevent the fuel gas tank 2 from being damaged during landing, etc. Moreover, the power unit 4 is arranged just below the radiator 6. That is, the multi-rotor aircraft 10 has its structural components arranged separately above and below the radiator 6. As a result, the center of gravity G1 of the multi-rotor aircraft 10 is located in the area where the radiator 6 exists in the direction of the center axis 1z in the height direction.

[0026] The resultant force of the resistance generated by the flying wind W1 is applied to the center of the flat surface 6p. The multirotor aircraft 10 of this embodiment is configured so that the center of the flat surface 6p overlaps with the center of gravity G1 of the multirotor aircraft 10. Therefore, for example, the resultant force of the resistance generated by the flying wind W1 does not generate a moment that rotates the multirotor aircraft 10 around the center of gravity G1. Therefore, even if the flying wind W1 generates resistance to the radiator 6, the multirotor aircraft 10 of this embodiment can still fly stably.

[0027] In addition, if Figure 3 As shown, the heat sink 6 is closer to the positive side in the X-axis direction (ie, Figure 3 The radiator 6 is configured so as to be inclined upward as it moves from one side to the other side in a direction perpendicular to the rotation axis 8a of the propeller 8 (i.e., the width direction center axis 1x direction). Therefore, when the multi-rotor aircraft 10 travels in the travel direction F1, the radiator 6 inclined relative to the travel direction can generate lift L1 by utilizing the flight wind W1. The multi-rotor aircraft 10 can fly more stably by the lift L1.

[0028] Furthermore, the center points 8c of the two propellers 8 are respectively located on the width direction center axis 1x. Figure 3 Although not described in the figure, the center points 8c of the other two propellers 8 are also located on the width direction center axis 1x. The width direction center axis 1x passes through the radiator 6 and extends in the X-axis direction. That is, the center point 8c of the propeller 8 is located on the plane passing through the radiator 6. As a result, the radiator 6 that generates resistance due to the flying wind W1 and the center point 8c of the propeller 8 that makes the multi-rotor aircraft 10 fly can be aligned in the height direction (that is, the Z-axis direction). As a result, the flight of the multi-rotor aircraft 10 can be further stabilized.

[0029] Although the above embodiments are described in detail, these embodiments are merely examples and are not intended to limit the scope of the technical solution. The techniques described in the technical solution include techniques for making various deformations and changes to the specific examples illustrated above. The following are examples of changes to the above embodiments.

[0030] (Variation 1) Although in the above-mentioned embodiment, the center of gravity G1 of the multi-rotor aircraft 10 coincides with the center of gravity of the radiator 6, in the variation, this is not limited to this, as long as the center of gravity G1 of the multi-rotor aircraft 10 is located in the area where the radiator 6 exists.

[0031] (Modification 2) In the above-described embodiment, the multirotor aircraft 10 includes four propellers 8, but the multirotor aircraft 10 of the modification may include two or three propellers 8, or may include five or more propellers 8.

[0032] (Variation 3) In the above embodiment, the fuel cell 4b is cooled by the radiator 6, but in a variation, the multi-rotor aircraft 10 may cool the battery. In this case, the multi-rotor aircraft 10 may not include the fuel cell 4b.

[0033] (Variation 4) In the above-described embodiment, the heat sink 6 is arranged so as to be inclined upward as it approaches the positive side in the X-axis direction. However, in a variation, the heat sink 6 may be arranged so as to be perpendicular to the X-axis direction.

[0034] (Variation 5) In the above embodiment, the fuel gas tank 2 is arranged directly above the radiator 6, and the power unit 4 is arranged directly below the radiator 6. However, in a variation, the power unit 4 may be arranged directly above the radiator 6, and the fuel gas tank 2 may be arranged directly below the radiator 6. In a further variation, the radiator 6 may be provided with a plurality of fuel gas tanks 2 in the width direction (i.e., Figure 1 A fuel gas tank 2 is arranged on one side (in the Y-axis direction) and a power unit 4 is arranged on the other side.

[0035] (Variation 6) In the above-described embodiment, the center points 8c of the four propellers 8 are located on the plane passing through the radiator 6. However, in a variation, the center points 8c of the four propellers 8 may not be located on the plane.

[0036] Although the specific examples of the present invention are described in detail above, these are merely examples and are not examples that limit the scope of the technical solution. The technologies recorded in the technical solution include technologies that make the specific examples illustrated above undergo various deformations and changes. The technical elements described in this specification or the drawings are technical elements that exert technical usefulness alone or through various combinations, and are not limited to the technical elements of the combination recorded in the technical solution at the time of application. In addition, the technologies illustrated in this specification or the drawings are technologies that can achieve multiple purposes at the same time, and achieving one of the purposes itself has technical usefulness.

Claims

1. A multi-rotor aircraft, comprising: propeller; a power unit that causes the propeller to rotate; a radiator, which is exposed to the outside and cools the power unit; a tank base supported on the housing of the power unit by four columns provided so as to extend in a direction parallel to the rotation axis of the propeller, in, The center of gravity of the multi-rotor aircraft is located in the radiator, The power unit comprises a fuel cell, The radiator cools the fuel cell. The multirotor aircraft further includes a fuel gas tank on the upper surface of the tank base, wherein the fuel gas tank stores fuel gas supplied to the fuel cell. A propeller support portion is connected to each of the four columns and extends in a direction perpendicular to the column and rotatably supports the propeller. The fuel gas tank is arranged directly above the radiator. The power unit is arranged directly below the radiator.

2. The multi-rotor aircraft according to claim 1, wherein: The radiator is arranged so as to be inclined upward from one side to the other side in a direction perpendicular to the rotation axis of the propeller.

3. The multi-rotor aircraft according to claim 1, wherein: The center point of the propeller is located on a plane passing through the radiator.

Images