Flying object

Abstract

The present specification relates to a flying body provided with a fuel cell for generating hydrogen using sodium borohydride, which is one kind of tetrahydroborate, and generating power using the hydrogen, and provides a technique for reducing the weight of a power generation device. A flying object disclosed in the present specification is provided with: an SBH container for storing sodium borohydride (SBH) that generates hydrogen when mixed with water; a water container for storing water mixed with the SBH; and a fuel cell stack that generates power using the hydrogen generated by the SBH. The outer wall of the flying body is also used as a part of the SBH container and a part of the water container. The water container is arranged above the SBH container, a bottom plate of the water container also serves as a top plate of the SBH container, and a valve is arranged on the bottom plate. In the technology disclosed in the present specification, the outer wall of the flying body also serves as part of an SBH container and part of a water container. With this configuration, a part of the power generation device can be reduced in weight.

Description

TECHNICAL FIELD

[0001] The technology disclosed in this specification relates to a flying body. BACKGROUND

[0002] A power generation system is disclosed in Patent Literature 1, which has a fuel cell that generates hydrogen by mixing water with a tetrahydroborate salt and generates power using the hydrogen. A flying body equipped with this power generation system is also disclosed in Patent Literature 1. The power generation system, which includes a container that stores the tetrahydroborate salt and a container that stores water, is housed inside the main body of the flying body. Furthermore, the power generation system has a pump for delivering water to the tetrahydroborate salt.

[0003] Patent Literature 1: Japanese Patent Application Publication No. 2024-001686 SUMMARY

[0004] In a flying body, the focus is on weight reduction. The technology disclosed in this specification relates to a flying body that has a fuel cell that generates hydrogen using sodium borohydride and generates power using the hydrogen, and provides a technology for reducing the weight of the power generation device, wherein the sodium borohydride is one type of tetrahydroborate salt.

[0005] The flying body disclosed in this specification has an SBH container that stores sodium borohydride (SBH) that generates hydrogen when mixed with water, a water container that stores water to be mixed with the SBH, and a fuel cell stack that generates power using the hydrogen generated by the SBH. The outer wall of the flying body serves as part of the SBH container and part of the water container. The water container is disposed above the SBH container, the floor of the water container serves as the ceiling of the SBH container, and a valve is provided on the floor.

[0006] In the technology disclosed in this specification, the outer wall of the flying body serves as part of the SBH container and part of the water container. With this configuration, it is possible to reduce the weight of part of the power generation device. Furthermore, the floor of the water container serves as the ceiling of the SBH container. This configuration also contributes to the weight reduction of the power generation device. Furthermore, a valve is provided on the floor of the water container. When the valve is opened, water is mixed with the SBH to generate hydrogen. When the valve is closed, the supply of water to the SBH is stopped. That is, in the technology disclosed in this specification, a pump for supplying water to the SBH is not needed. By this point, it is also possible to reduce the weight of the power generation device.

[0007] The details of the technology disclosed in this specification and further improvements will be described in the "DETAILED DESCRIPTION" below. BRIEF DESCRIPTION OF DRAWINGS

[0008] Figure 1 is a plan view of the flying body (rotorcraft) of the embodiment.

[0009] Figure 2 is a side view of the rotorcraft.

[0010] Figure 3 is a cross-sectional view taken along the III-III line of Figure 2 . DETAILED DESCRIPTION

[0011] Reference Figures 1-3 The flying body 10 of the embodiment is described. Figure 1 and Figure 2 are a plan view and a side view of the flying body 10, respectively. Figure 3 is a cross-sectional view taken along the III-III line of Figure 2 . The flying body 10 is a rotorcraft having a plurality of rotors 12, and is a so-called unmanned aerial vehicle that flies by remote operation. The X axis, Y axis of the coordinate system in the figure respectively indicate the front-rear direction, lateral direction of the flying body 10. The +Z direction indicates the vertical upward direction.

[0012] The flying body 10 as a rotorcraft is provided with a main body 11, four rotors 12, a fuel cell stack 18, and a flow path tube 17. Hereinafter, the expression "fuel cell stack" is expressed as "FC stack" for convenience of explanation.

[0013] The flying body 10 flies by generating lift by the four rotors 12. The four rotors 12 are respectively arranged at the four corners of the main body 11. The rotors 12 are driven by motors 13. The motors 13 are driven by electric power generated by the FC stack 18. In addition, a battery is provided in the main body 11, and the remaining electric power, which is not consumed by the motors 13, of the electric power generated by the FC stack 18 is accumulated in the battery. In the case where the electric power of the FC stack 18 for driving the motors 13 is insufficient, the electric power of the battery is used. A device or the like that converts the electric power generated by the FC stack 18 (and the electric power of the battery) into electric power suitable for driving of the motors 13 is mounted in the main body 11, but the illustration and explanation of the device are omitted.

[0014] The SBH container 16 that stores sodium borohydride 21 (SBH 21) and the water container 15 that stores water 22 are provided inside the main body 11. As shown in Figure 3 , the outer wall 11a of the main body 11 of the flying body 10 serves as a part of the SBH container 16 and a part of the water container 15. Also, the water container 15 is arranged directly above the SBH container 16, and the floor 15a of the water container 15 serves as the ceiling of the SBH container 16.

[0015] A valve 19 is provided on the bottom plate 15a. The bottom plate 15a is in the shape of a mortar with a central portion lower than a peripheral portion, and the valve 19 is provided at the lowest position thereof. If the valve 19 is opened, the water 22 of the water container 15 falls into the SBH container 16, and the water 22 is mixed with the SBH 21. As is well known, hydrogen is generated when the SBH 21 is mixed with the water 22. The hydrogen generated in the SBH container 16 is sent to the FC stack 18 through the flow path pipe 17. In addition, the FC stack 18 can be a device made using the existing technology, and therefore the internal structure of the FC stack 18 is omitted in Figure 3 If the valve 19 is closed, the falling of the water 22 into the SBH container 16 is stopped.

[0016] The SBH 21 is stored in the SBH container 16 under normal pressure, and the water 22 is also stored in the water container 15 under normal pressure. In a fuel cell automobile or the like, a high-pressure hydrogen storage tank is generally used as a hydrogen source, but in order to obtain high pressure, the weight of the high-pressure hydrogen tank becomes large. The flying body 10 stores the SBH 21 and the water 22 under normal pressure, and therefore the dry weight (weight excluding the SBH and the water) is lighter than that of the high-pressure hydrogen storage tank. Therefore, it is important to reduce the weight of the flying body.

[0017] Furthermore, the outer wall 11a of the flying body 10 functions as part of the water container 15 and part of the SBH container 16. This structure also contributes to the reduction in the weight of the device required for power generation. Furthermore, the water container 15 is located vertically above the SBH container 16, and the bottom plate 15a of the water container 15 functions as the top plate of the SBH container 16. This structure also contributes to the reduction in the weight of the device required for power generation. Furthermore, if the valve 19 is opened, the water 22 of the water container 15 falls into the SBH container 16, and the water 22 is mixed with the SBH 21. The water 22 is mixed with the SBH 21 only by the simple valve 19. A pump for sending the water 22 to the SBH is also not required. This structure also contributes to the reduction in the weight of the device required for power generation.

[0018] The FC stack 18 is disposed below the main body 11. In other words, the FC stack 18 is disposed below the SBH container 16. The hydrogen generated in the SBH container 16 flows into the FC stack 18 without the use of a pump. In addition, the main body 11 is provided with four legs 14, and the bottom of the FC stack 18 is located at a position higher than the lower ends of the legs 14.

[0019] As described above, the flying body 10 of the embodiment can reduce the weight of the device required for power generation. The flying body 10 of the embodiment is characterized as follows. The flying body 10 is provided with the SBH container 16 that stores the SBH, the FC stack 18, and the water container 15 that stores the water mixed with the SBH. The outer wall 11a of the main body 11 of the flying body 10 functions as a part of the SBH container 16 and a part of the water container 15. The water container 15 is arranged above the SBH container 16, and the bottom plate 15a of the water container 15 functions as the top plate of the SBH container 16. The valve 19 is provided on the bottom plate 15a, and if the valve 19 is opened, the water 22 falls into the SBH container 16, and the water 22 is mixed with the SBH 21 to generate hydrogen. The FC stack 18 generates power using the hydrogen generated by the SBH, and the flying body 10 flies using the power of the motor 13.

[0020] The matters to be noted in relation to the technology described in the embodiment are described. The flying body 10 of the embodiment is a rotorcraft that flies without a pilot. The technology disclosed in the present specification is not limited to the rotorcraft, and can be applied to a fixed-wing aircraft. Also, the technology disclosed in the present specification is not limited to the unmanned aerial vehicle, and can be applied to a manned flying body.

[0021] Also, the technology disclosed in the present specification is not limited to the flying body that obtains the lift using the power of the motor 13 driven by the FC stack 18. The power of the FC stack 18 can also be used to drive devices other than the lift generating device, such as a controller or a sensor.

[0022] The above describes the specific examples of the present application in detail, but these are only examples, and do not limit the claims. The technology described in the claims includes technology obtained by various modifications and changes to the above-described specific examples. The technical elements described in the specification or the drawings exhibit technical usefulness alone or in various combinations, and are not limited to the combinations described in the claims at the time of filing. Also, the technology exemplified in the specification or the drawings can achieve multiple purposes at the same time, and achieving only one purpose itself also has technical usefulness.

[0023] Explanation of symbols

[0024] 10 - flying body, 11 - main body, 11a - outer wall, 12 - rotor, 13 - motor, 14 - leg, 15 - water container, 15a - bottom plate, 16 - SBH container, 17 - flow path tube, 18 - fuel cell stack, 19 - valve.

Claims

1. A flying vehicle, characterized in that, have: SBH containers contain sodium borohydride, which produces hydrogen if mixed with water. A water container that stores water mixed with the sodium borohydride; and A fuel cell stack that uses hydrogen produced from the sodium borohydride to generate electricity. The outer wall of the flying body serves as part of both the SBH container and the water container. The water container is positioned above the SBH container, and the bottom plate of the water container also serves as the top plate of the SBH container. A valve is provided on the bottom plate.

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