flying object

Abstract

This specification relates to an aircraft equipped with a fuel cell that generates hydrogen using sodium borohydride, a type of tetrahydroborate, and uses that hydrogen to generate electricity, and provides a technology for reducing the weight of the power generation device. [Solution] The aircraft disclosed herein comprises an SBH container for storing sodium borohydride (SBH), which generates hydrogen when mixed with water; a water container for storing water to be mixed with the SBH; and a fuel cell stack for generating electricity with the hydrogen generated by the SBH. The outer wall of the aircraft serves as both a part of the SBH container and a part of 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, with a valve provided on the bottom plate. In the technology disclosed herein, the outer wall of the aircraft serves as both a part of the SBH container and a part of the water container. This structure allows for weight reduction of a portion of the power generation device.

Description

Technical Field

[0001] The technology disclosed in this specification relates to aircraft.

Background Art

[0002] Patent Document 1 discloses a power generation system including a fuel cell that generates hydrogen by mixing tetrahydroborate with water and generates power using the hydrogen. Patent Document 1 further discloses an aircraft equipped with the power generation system. The power generation system including a container for storing tetrahydroborate and a container for storing water is housed inside the aircraft body. Further, the power generation system includes a pump for sending water to the tetrahydroborate.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0004] Weight reduction is emphasized in aircraft. This specification relates to an aircraft equipped with a fuel cell that generates hydrogen using sodium borohydride (SBH), which is a type of tetrahydroborate, and generates power using the hydrogen, and provides a technology for reducing the weight of the power generation device.

Means for Solving the Problems

[0005] The aircraft disclosed in this specification includes an SBH container for storing sodium borohydride (SBH) that generates hydrogen when mixed with water, a water container for storing 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 aircraft also serves as part of the SBH container and part of the water container. The water container is disposed above the SBH container, and the bottom plate of the water container also serves as the top plate of the SBH container, and a valve is provided on the bottom plate.

[0006] In the technology disclosed herein, the outer wall of the aircraft serves as both part of the SBH container and part of the water container. This structure allows for weight reduction of a portion of the power generation device. Furthermore, the bottom plate of the water container also serves as the top plate of the SBH container. This structure also contributes to weight reduction of the power generation device. In addition, a valve is provided in the bottom plate of the water container. When the valve is opened, water mixes with the SBH to generate hydrogen. When the valve is closed, the supply of water to the SBH stops. In other words, in the technology disclosed herein, a pump for supplying water to the SBH is not required. This also contributes to weight reduction of the power generation device.

[0007] Details of the technology disclosed herein and further improvements are described in the following "Modes for Carrying Out the Invention". [Brief explanation of the drawing]

[0008] [Figure 1] This is a plan view of the aircraft (rotary-wing aircraft) in the embodiment. [Figure 2] This is a side view of a rotary-wing aircraft. [Figure 3] This is a cross-sectional view along line III-III in Figure 2. [Modes for carrying out the invention]

[0009] The embodiment of the aircraft 10 will be described with reference to Figures 1-3. Figures 1 and 2 are a plan view and a side view of the aircraft 10, respectively. Figure 3 is a cross-sectional view along line III-III in Figure 2. The aircraft 10 is a rotary-wing aircraft having multiple rotors 12, and is a so-called drone that flies by remote control. The X and Y axes of the coordinate system in the figures represent the front-to-back and lateral directions of the aircraft 10, respectively. The +Z direction represents the vertically upward direction.

[0010] The rotary-wing aircraft 10 comprises a main body 11, four rotors 12, a fuel cell stack 18, and flow path pipes 17. For convenience of explanation, the "fuel cell stack" will be referred to as the "FC stack" below.

[0011] The aircraft 10 flies by generating lift with four rotors 12. Each of the four rotors 12 is positioned at one of the four corners of the main body 11. The rotors 12 are driven by motors 13. The motors 13 are driven by power generated by the FC stack 18. The main body 11 is equipped with a battery, and any surplus power generated by the FC stack 18 that is not consumed by the motors 13 is stored in the battery. If the power from the FC stack 18 is insufficient to drive the motors 13, power from the battery is used. The main body 11 is equipped with devices that convert the power generated by the FC stack 18 (and the battery power) into power suitable for driving the motors 13, but the illustration and explanation of these devices are omitted.

[0012] The main body 11 contains an SBH container 16 for storing sodium borohydride 21 (SBH21) and a water container 15 for storing water 22. As shown in Figure 3, the outer wall 11a of the main body 11 of the aircraft 10 serves as part of both the SBH container 16 and the water container 15. The water container 15 is positioned directly above the SBH container 16, and the bottom plate 15a of the water container 15 also serves as the top plate of the SBH container 16.

[0013] A valve 19 is provided on the bottom plate 15a. The bottom plate 15a has a mortar-like shape, with the central part lower than the peripheral part, and the valve 19 is located at the lowest point. When the valve 19 is opened, the water 22 from the water container 15 falls into the SBH container 16, and the water 22 mixes with SBH 21. As is well known, SBH 21 generates hydrogen when mixed with water 22. The hydrogen generated in the SBH container 16 is sent to the FC stack 18 through the flow channel pipe 17. Note that the FC stack 18 can be a device made using conventional technology, so the internal structure of the FC stack 18 is not shown in Figure 3. When the valve 19 is closed, the water 22 stops falling into the SBH container 16.

[0014] SBH21 is stored in the SBH container 16 at atmospheric pressure, and water 22 is also stored in the water container 15 at atmospheric pressure. In fuel cell vehicles and the like, high-pressure hydrogen tanks are generally used as the hydrogen source, but high-pressure hydrogen tanks are heavy in order to withstand high pressure. The aircraft 10 can store SBH21 and water 22 at atmospheric pressure, so its dry weight (weight excluding SBH and water) is lighter than that of a high-pressure hydrogen tank. Therefore, it is suitable for aircraft where weight reduction is important.

[0015] Furthermore, the outer wall 11a of the flying body 10 serves as both part of the water container 15 and part of the SBH container 16. This structure also contributes to reducing the weight of the power generation equipment. In addition, the water container 15 is located directly above the SBH container 16, and the bottom plate 15a of the water container 15 also serves as the top plate of the SBH container 16. This structure also contributes to reducing the weight of the power generation equipment. Moreover, when the valve 19 is opened, the water 22 from the water container 15 falls into the SBH container 16, and the water 22 mixes with the SBH 21. The water 22 can be mixed with the SBH 21 using only a simple valve 19. A pump to send the water 22 to the SBH is not required. This structure also contributes to reducing the weight of the power generation equipment.

[0016] The FC stack 18 is located beneath the main body 11. In other words, the FC stack 18 is located beneath the SBH container 16. Hydrogen generated in the SBH container 16 flows to the FC stack 18 without the need for a pump. The main body 11 is equipped with four legs 14, and the bottom of the FC stack 18 is positioned above the lower ends of the legs 14.

[0017] As described above, the aircraft 10 of the embodiment can reduce the weight of the equipment required for power generation. The features of the aircraft 10 of the embodiment are as follows. The aircraft 10 is equipped with an SBH container 16 for storing SBH, an FC stack 18, and a water container 15 for storing water to be mixed with SBH. The outer wall 11a of the main body 11 of the aircraft 10 serves as part of both the SBH container 16 and the water container 15. The water container 15 is positioned above the SBH container 16, and the bottom plate 15a of the water container 15 also serves as the top plate of the SBH container 16. A valve 19 is provided on the bottom plate 15a, and when the valve 19 is opened, water 22 falls into the SBH container 16, and the water 22 and SBH 21 mix to generate hydrogen. The FC stack 18 generates electricity with the hydrogen generated by the SBH, and the aircraft 10 flies by driving the motor 13 with that electricity.

[0018] The following points should be noted regarding the technology described in the examples. The aircraft 10 in the examples is an unmanned rotary-wing aircraft. The technology disclosed herein is not limited to rotary-wing aircraft but can be applied to fixed-wing aircraft. Furthermore, the technology disclosed herein is not limited to drones but can also be applied to manned aircraft.

[0019] Furthermore, the applications of the technology disclosed herein are not limited to aircraft that generate lift by driving the motor 13 with the power of the FC stack 18. The power of the FC stack 18 may also be used to drive devices other than the lift generator, such as controllers or sensors.

[0020] Although specific examples of the present invention have been described in detail above, these are merely illustrative and do not limit the scope of the claims. The technologies described in the claims include various modifications and changes to the specific examples illustrated above. The technical elements described in this specification or drawings exhibit technical usefulness individually or in various combinations, and are not limited to the combinations described in the claims at the time of filing. Furthermore, the technologies illustrated in this specification or drawings can achieve multiple objectives simultaneously, and achieving even one of these objectives itself constitutes technical usefulness. [Explanation of symbols]

[0021] 10: Aircraft 11: Body 11a: Outer wall 12: Rotor 13: Motor 14: Leg 15: Water container 15a: Bottom plate 16: SBH container 17: Flow path pipe 18: Fuel cell stack 19: Valve

Claims

[Claim 1] It is an flying object, An SBH container storing sodium borohydride, which generates hydrogen when mixed with water, A water container storing the water to be mixed with the sodium borohydride, A fuel cell stack that generates electricity using the hydrogen produced by the sodium borohydride, It is equipped with, The outer wall of the aircraft serves as both a part of the SBH container and a part of the water container. The water container is positioned above the SBH container, the bottom plate of the water container also serves as the top plate of the SBH container, and a valve is provided on the bottom plate. A flying object.

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