aircraft

Abstract

To reduce a drive sound transmitted to a cabin from a drive source.SOLUTION: An aircraft 10, which comprises a cabin 24 for being boarded by a crew member and a drive source 34 for being driven by using supplied fuel FL, includes a tank unit 28 that is arranged between the cabin 24 and the drive source 34 and in which a plurality of fuel tanks 40 for storing the fuel FL are stacked.SELECTED DRAWING: Figure 2

Description

[Technical Field]

[0001] The present invention relates to aircraft. [Background technology]

[0002] Patent Document 1 discloses an aircraft equipped with an internal combustion engine, a generator, and multiple rotors. The generator generates electricity when driven by the internal combustion engine. The multiple rotors rotate using the electricity generated by the generator. The rotation of the multiple rotors generates thrust or lift to fly the aircraft. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] US Patent Application Publication No. 2020 / 0115045 Summary of the Invention [Problem to be solved by the invention]

[0004] Drive sources such as internal combustion engines and generators generate drive noise, which can reverberate inside the cabin of an aircraft.

[0005] One approach to reducing noise is to install a soundproof wall between the drive source and the cabin. However, installing a soundproof wall increases the weight of the aircraft.

[0006] The present invention aims to solve the above-mentioned problems. [Means for solving the problem]

[0007] One aspect of the present invention is an aircraft comprising a cabin for occupants and a power source that is powered by supplied fuel, and a tank unit arranged between the cabin and the power source and comprising a stack of multiple fuel tanks that store the fuel. [Effects of the Invention]

[0008] According to the present invention, the drive noise transmitted from the drive source to the cabin is reduced, and an increase in the weight of the aircraft due to the soundproof wall is also suppressed. [Brief explanation of the drawings]

[0009] [Figure 1] FIG. 1 is a perspective view of an aircraft according to an embodiment. [Figure 2] Fig. 2A is a diagram illustrating the inside of the fuselage, and Fig. 2B is a diagram illustrating the state after the fuel tank that supplied fuel to the drive source in Fig. 2A has become empty. [Figure 3] FIG. 3 is a diagram illustrating the inside of the fuselage according to the first modification. [Figure 4] FIG. 4 is a diagram illustrating the inside of the fuselage according to the second modification. [Figure 5] FIG. 5 is a diagram for explaining the inside of the fuselage according to the third modification. [Figure 6] Fig. 6A is a diagram for explaining the inside of a fuselage according to Modification 4. Fig. 6B is an end view taken along line VIB-VIB in Fig. 6A. DETAILED DESCRIPTION OF THE INVENTION

[0010] [Embodiment] FIG. 1 is a perspective view of an aircraft 10 according to an embodiment.

[0011] Note that multiple arrows are shown in each drawing, including Figure 1. Arrow DF indicates the forward direction of aircraft 10. Arrow DB indicates the rearward direction of aircraft 10. Arrow DL indicates the leftward direction of aircraft 10. Arrow DR indicates the rightward direction of aircraft 10. Arrow DU indicates the upward direction of aircraft 10. Arrow DD indicates the downward direction of aircraft 10. The forward / backward direction, left / right direction, and up / down direction are perpendicular to one another.

[0012] The aircraft 10 includes a fuselage 12, a pair of cruise rotors 14, a rear wing 16, a front wing 18, a pair of booms 20, and a number of takeoff and landing rotors 22.

[0013] The fuselage 12 is bilaterally symmetrical. The fuselage 12 is long in the front-to-rear direction. The central axis LA of the fuselage 12 extends parallel to the front-to-rear direction.

[0014] Each of the pair of cruise rotors 14 is a device (rotor) that generates thrust to propel the aircraft 10 forward. The pair of cruise rotors 14 is installed on the left and right sides of the rear of the fuselage 12, centered on a central axis LA. The pair of cruise rotors 14 are driven by multiple motors. The multiple motors that drive the pair of cruise rotors 14 are not shown in the figure.

[0015] The rear wing 16 is a main wing installed on the upper part of the fuselage 12. The front wing 18 is a canard installed on the upper part of the fuselage 12, between the rear wing 16 and the nose 10f of the aircraft 10. The front wing 18 and the rear wing 16 generate lift by catching wind flowing in the rearward direction.

[0016] Each of the pair of booms 20 is a member on which a plurality of takeoff and landing rotors 22 are installed. Each of the pair of booms 20 is long in the front-to-rear direction. The pair of booms 20 are arranged in a left-right pair around the central axis LA. Of the pair of booms 20, the left boom 20 is arranged to the left of the fuselage 12. Of the pair of booms 20, the right boom 20 is arranged to the right of the fuselage 12. In addition, the pair of booms 20 are connected to the front wing 18 and the rear wing 16.

[0017] Each of the multiple takeoff and landing rotors 22 is a device (rotor) that generates lift by rotating. The multiple takeoff and landing rotors 22 are arranged in pairs on the left and right sides around a central axis LA. The multiple takeoff and landing rotors 22 are driven by multiple motors. The multiple motors that drive the multiple takeoff and landing rotors 22 are not shown in the figure.

[0018] FIG. 2A is a diagram illustrating the inside of the fuselage 12. FIG.

[0019] The fuselage 12 includes a front chamber (cabin) 24, a rear chamber 26, a tank unit 28, a plurality of valves 30, and a control unit (valve control unit) 32. The fuselage 12 also has an inner wall 12a that forms the interior and an outer wall 12b that forms the exterior. The front chamber 24 and the rear chamber 26 are located inside the inner wall 12a.

[0020] The front cabin 24 is a compartment where the crew rides. The front cabin 24 is located forward of the rear cabin 26. The cockpit of the aircraft 10 is located in the fuselage 12, forward of the front cabin 24. However, illustrations of the equipment inside the front cabin 24 and the cockpit are omitted.

[0021] The rear chamber 26 is a chamber in which the drive source 34 is installed. A motor may be installed in the rear chamber 26. This motor is, for example, a motor for driving the cruise rotor 14.

[0022] The driving source 34 includes, for example, an engine 36 and a generator 38. The engine 36 is driven by consuming fuel FL. The generator 38 generates electricity in response to the driving of the engine 36. The driving source 34 may include a battery. The battery stores the electricity generated by the generator 38. The number of each of the engine 36, the generator 38, and the battery may be one or more.

[0023] The drive source 34 supplies power to equipment on the aircraft 10. For example, the drive source 34 supplies power to a plurality of motors for rotating the pair of cruise rotors 14.

[0024] However, when the drive source 34 is driven, it emits a drive sound DS. In consideration of this, in this embodiment, the tank unit 28 is disposed between the front chamber 24 and the rear chamber 26 (drive source 34). The front chamber 24 and the rear chamber 26 are separated by the tank unit 28 and the fuel FL stored in the tank unit 28.

[0025] The tank unit 28 is a device that stores the fuel FL. The tank unit 28 is disposed between the front chamber 24 and the rear chamber 26, thereby reducing the drive noise DS transmitted from the drive source 34 to the front chamber 24. The fuel FL stored in the tank unit 28 further reduces the drive noise DS transmitted from the drive source 34 to the front chamber 24.

[0026] When a motor is installed in the rear chamber 26, the tank unit 28 and the fuel FL stored in the tank unit 28 also reduce the driving noise of the motor transmitted from the rear chamber 26 to the front chamber 24.

[0027] The tank unit 28 is preferably disposed above the center of gravity Ga of the aircraft 10 excluding the tank unit 28 and the fuel FL. This prevents the center of gravity Gb of the aircraft 10 including the fuel FL from being positioned differently from the center of gravity Ga in the horizontal direction.

[0028] The center of gravity Ga illustrated in Fig. 2A indicates the position of the center of gravity of the aircraft 10 in the longitudinal direction, excluding the tank unit 28 and fuel FL. The tank unit 28 is disposed above the center of gravity Ga. The centers of gravity Ga and Gb illustrated in Fig. 2A are at the same position in the longitudinal direction (horizontal direction).

[0029] The tank unit 28 includes a plurality of fuel tanks 40. Each of the plurality of fuel tanks 40 is a tank that stores fuel FL. The plurality of fuel tanks 40 are stacked in the front-to-rear direction. That is, the plurality of fuel tanks 40 are stacked in the direction in which the front chamber 24 and the rear chamber 26 are arranged.

[0030] Therefore, even if one of the multiple fuel tanks 40 becomes empty, as long as fuel FL remains in at least one of the remaining fuel tanks 40, that fuel FL reduces the drive noise DS transmitted from the drive source 34 to the front chamber 24 (see also FIG. 2B). Note that in both FIGS. 2A and 2B, the fuel FL contained in the fuel tank 40 is represented by a polka dot pattern.

[0031] The amount of fuel FL supplied from the tank unit 28 to the driving source 34 is controlled by a plurality of valves 30 and a control unit 32. The plurality of valves 30 correspond to a plurality of fuel tanks 40, respectively. A fuel tank 40 whose corresponding valve 30 is open can supply fuel FL to the driving source 34. On the other hand, a fuel tank 40 whose corresponding valve 30 is closed does not supply fuel FL to the driving source 34.

[0032] Of the multiple valves 30 shown in FIG. 2A, the valves 30 painted in white are valves 30 in an open state (the same applies to FIG. 2B). Also, of the multiple valves 30 shown in FIG. 2A, the valves 30 painted in black are valves 30 in a closed state (the same applies to FIG. 2B). Therefore, in FIG. 2A, fuel FL is supplied to the driving source 34 only from the rearmost fuel tank 40 of the three fuel tanks 40 lined up in the front-to-rear direction. The open state and closed state of each of the multiple valves 30 are switched based on control performed by the control unit 32.

[0033] For the sake of illustration, the multiple valves 30 are arranged above the multiple fuel tanks 40, separated by the inner wall 12a of the fuselage 12. However, the multiple valves 30 may also be arranged below, to the right, or to the left, etc., of the multiple fuel tanks 40, separated by the inner wall 12a.

[0034] The control unit 32 is, for example, a computer including a processor and a memory. In this case, the functions of the control unit 32 described below are realized by the processor executing a program stored in the memory. However, the control unit 32 may also be realized by a processing circuit such as an ASIC (Application Specific Integrated Circuit), an FPGA (Field-Programmable Gate Array), or a discrete device. The control unit 32 is installed in the rear chamber 26. However, the control unit 32 may also be installed in a location other than the rear chamber 26.

[0035] The control unit 32 controls the amount of fuel FL supplied from the tank unit 28 to the driving source 34 by controlling the opening and closing of the multiple valves 30. The control unit 32 selects one of the multiple valves 30 and opens the selected valve 30. The fuel FL in the fuel tank 40 corresponding to the opened valve 30 is supplied to the driving source 34.

[0036] FIG. 2B is a diagram for explaining a state after the fuel tank 40 that has been supplying fuel FL to the driving source 34 in FIG. 2A has become empty.

[0037] After one fuel tank 40 is emptied, the control unit 32 opens the valve 30 corresponding to the other fuel tank 40 that has fuel FL remaining. This makes it possible to maintain a state in which at least one of the multiple fuel tanks 40 is full of fuel FL for as long as possible. By maintaining a state in which at least one fuel tank 40 is full of fuel FL for as long as possible, it is possible to maintain the soundproofing effect of the fuel FL for as long as possible.

[0038] The remaining amount of fuel FL in each of the plurality of fuel tanks 40 is detected based on, for example, a detection signal from a predetermined sensor that detects the remaining amount of fuel FL in the fuel tank 40 or the position of the liquid level in the fuel tank 40. The control unit 32 may also close the valve 30 corresponding to the empty fuel tank 40.

[0039] The control unit 32 may select the valve 30 to open randomly or in a predetermined order. In either case, however, the control unit 32 selects the valve 30 corresponding to the fuel tank 40 in which fuel FL remains. For example, FIG. 2B illustrates three fuel tanks 40 (401, 402, 403). Of the three fuel tanks 40, the rearmost fuel tank 403 is empty. In this case, the control unit 32 opens the valve 30 corresponding to the frontmost fuel tank 401 or the intermediate fuel tank 402.

[0040] The predetermined order is an order in which the valve 30 corresponding to the fuel tank 40 containing fuel FL and farthest from the center of gravity Gb of the aircraft 10 is opened first. For example, in FIG. 2B , fuel FL remains in fuel tank 401 and fuel tank 402. However, between fuel tank 401 and fuel tank 402, fuel tank 401 is located farther from the center of gravity Gb than fuel tank 402. In this case, the control unit 32 opens the valve 30 corresponding to fuel tank 401. Note that if there are two fuel tanks 40 that are the same distance from the center of gravity Gb, the valve 30 corresponding to either of the two fuel tanks 40 may be selected.

[0041] The fuel FL in the fuel tank 40 farthest from the center of gravity Gb is supplied to the driving source 34 first, thereby suppressing fluctuations in the position of the center of gravity Gb caused by the supply of fuel FL.

[0042] The control unit 32 may select the valves 30 to open in an order other than the order in which the valves 30 corresponding to the fuel tanks 40 that contain fuel FL and are farthest from the center of gravity Gb of the aircraft 10 are opened first.

[0043] This completes the description of the aircraft 10 according to this embodiment. The tank unit 28 includes the front chamber (24) and the drive source (34), and can be applied to all aircraft that use fuel (FL).

[0044] [Variations] Modifications of the above embodiment are described below. However, descriptions that overlap with the above embodiment will be omitted as much as possible in the following description. Components that have already been described in the above embodiment will be assigned the same reference numerals as in the above embodiment unless otherwise specified.

[0045] (Variation 1) 3 is a diagram for explaining the inside of the body 12 according to Modification 1. For simplicity of illustration, the multiple valves 30 and the control unit 32 are omitted from the illustration.

[0046] The aircraft 10 may further include a soundproof wall 42 installed between the front compartment 24 and the tank unit 28. The soundproof wall 42 reduces the driving noise DS that passes through the tank unit 28 (fuel FL).

[0047] The drive noise DS is reduced by the fuel FL in the tank unit 28 before it reaches the soundproof wall 42. Therefore, the thickness of the soundproof wall 42 in the fore-and-aft direction can be kept to a minimum. This allows the weight of the soundproof wall 42 to be kept to a minimum. According to this modification, it is possible to further reduce the transmission of the drive noise DS to the front compartment 24 while minimizing the increase in weight of the aircraft 10 due to the addition of the soundproof wall.

[0048] (Variation 2) 4 is a diagram for explaining the inside of the body 12 according to Modification 2. For simplicity of illustration, the multiple valves 30 and the control unit 32 are omitted from the illustration.

[0049] The aircraft 10 may further include a soundproof wall 44 installed between the tank unit 28 and the drive source 34. The soundproof wall 44 reduces the drive noise DS transmitted to the tank unit 28 (fuel FL).

[0050] The drive noise DS is reduced not only by the soundproof wall 44 but also by the fuel FL in the tank unit 28. Therefore, the thickness of the soundproof wall 44 in the fore-and-aft direction can be kept to a minimum. This also allows the weight of the soundproof wall 44 to be kept to a minimum. According to this modification, it is possible to further reduce the transmission of the drive noise DS to the front compartment 24 while minimizing the increase in weight of the aircraft 10 due to the addition of the soundproof wall.

[0051] (Variation 3) 5 is a diagram for explaining the inside of the body 12 according to Modification 3. For simplicity of illustration, the multiple valves 30 and the control unit 32 are omitted from the illustration.

[0052] The aircraft 10 may further include a soundproof wall 46 installed between two adjacent fuel tanks 40. The soundproof wall 46 reduces the drive noise DS transmitted between the two adjacent fuel tanks 40.

[0053] Before the drive noise DS reaches the soundproof wall 46, it is reduced by the fuel FL in the fuel tank 40 located rearward of the soundproof wall 46. The drive noise DS is also reduced by the fuel FL in the fuel tank 40 located forward of the soundproof wall 46. Therefore, the thickness of the soundproof wall 46 in the fore-and-aft direction can be kept to a minimum. This allows the weight of the soundproof wall 46 to be kept to a minimum. According to this modification, it is possible to further reduce the transmission of the drive noise DS to the front compartment 24 while minimizing the increase in weight of the aircraft 10 due to the addition of a soundproof wall.

[0054] 5 illustrates two soundproof walls 46 (461, 462). Soundproof wall 461 is a soundproof wall 46 arranged between fuel tank 401 and fuel tank 402. Soundproof wall 462 is a soundproof wall 46 arranged between fuel tank 402 and fuel tank 403. In this way, when the number of fuel tanks 40 is three or more, aircraft 10 may be provided with a plurality of soundproof walls 46. On the other hand, for example, one of soundproof wall 461 and soundproof wall 462 may be omitted as necessary.

[0055] (Variation 4) Fig. 6A is a diagram illustrating the interior of the body 12 according to Modification 4. Fig. 6B is an end view taken along line VIB-VIB in Fig. 6A. For simplicity, the multiple valves 30 and the control unit 32 are not shown.

[0056] A gap 48 that connects the front chamber 24 and the driving source 34 may be formed between the tank unit 28 and the inner wall 12a of the body 12. For example, the cross section of the tank unit 28 illustrated in FIG. 6B is rectangular. In contrast, the inner wall 12a illustrated in FIG. 6B is cylindrical (elliptical). In this case, a gap 48 is formed between the tank unit 28 and the inner wall 12a.

[0057] There is a risk that the driving sound DS of the drive source 34 will be transmitted to the front compartment 24 through the gap 48. In light of this, the aircraft 10 may further include a soundproof wall 50. The soundproof wall 50 is provided between the tank unit 28 and the inner wall 12a so as to fill the gap 48. The soundproof wall 50 reduces the driving sound DS that is transmitted to the front compartment 24 through the gap 48.

[0058] The soundproof wall 50 preferably has a sufficient thickness in the front-to-rear direction to reduce the drive noise DS transmitted through the gap 48. However, the area of ​​the soundproof wall 50 in the up-down and left-to-right directions need only be the minimum required to fill the gap 48. Therefore, the weight of the soundproof wall 50 can be kept to a minimum. According to this modification, it is possible to further reduce the transmission of the drive noise DS to the front compartment 24 while minimizing the increase in the weight of the aircraft 10 due to the addition of the soundproof wall.

[0059] The soundproof wall 50 is connected to the tank unit 28. The soundproof wall 50 is connected to the tank unit 28 by, for example, screw fastening. However, the method of connecting the soundproof wall 50 to the tank unit 28 is not limited to screw fastening. The soundproof wall 50 may be adhered to the tank unit 28 by an adhesive. Furthermore, the soundproof wall 50 may be integrally molded with the tank unit 28.

[0060] (Variation 5) A power control unit for controlling the motors and a power drive system may be installed in the rear compartment 26.

[0061] (Combination of multiple modifications) The above-described multiple modifications may be combined as appropriate within a range that does not contradict each other.

[0062] [Inventions Obtained from the Embodiments] The invention that can be understood from the above-described embodiment and modifications will be described below.

[0063] An aircraft (10) having a cabin (24) for passengers and a drive source (34) that is driven by supplied fuel (FL) is provided with a tank unit (28) that is arranged between the cabin and the drive source and that has a plurality of stacked fuel tanks (40) that store the fuel.

[0064] This not only reduces the drive noise transmitted from the drive source to the cabin, but also prevents the soundproof wall from increasing the weight of the aircraft.

[0065] The plurality of fuel tanks may be stacked in the direction in which the cabin and the driving source are aligned, so that if fuel remains in at least one of the plurality of fuel tanks, that fuel reduces driving noise transmitted from the driving source to the cabin.

[0066] The aircraft may further include a plurality of valves (30) provided corresponding to each of the plurality of fuel tanks, and a valve control unit (32) that controls the amount of fuel supplied from the tank unit to the driving source by controlling the opening and closing of the plurality of valves, and the valve control unit may supply the fuel from one of the fuel tanks to the driving source when one of the fuel tanks is empty. This allows the state in which the driving noise transmitted to the cabin is reduced by the fuel in at least one fuel tank to be maintained for as long as possible.

[0067] The valve control unit may select the fuel tank that supplies the fuel to the driving source in a predetermined order and cause the fuel from the selected fuel tank to be supplied to the driving source, thereby making it possible to predict, based on the predetermined order, the displacement of the center of gravity in response to a decrease in fuel.

[0068] The predetermined order may be determined so that the fuel in the fuel tank farthest from the center of gravity (Gb) of the aircraft including the fuel is supplied to the drive source first, thereby stabilizing the center of gravity of the aircraft during flight.

[0069] The tank unit may be located above the center of gravity (Ga) of the aircraft excluding the tank unit and the fuel, thereby stabilizing the center of gravity of the aircraft during flight.

[0070] The aircraft may further include a first soundproof wall (42) installed between the cabin and the tank unit, whereby drive noise passing through the tank unit (fuel) is reduced by the first soundproof wall.

[0071] The aircraft may further include a second soundproof wall (44) installed between the tank unit and the drive source, whereby drive noise transmitted from the drive source to the tank unit (fuel) is reduced by the second soundproof wall.

[0072] The aircraft may further include a third soundproof wall (46) installed between two adjacent fuel tanks, whereby drive noise passing through the tank unit is reduced by the third soundproof wall.

[0073] The cabin, the drive source, and the tank unit are provided inside the fuselage (12) of the aircraft, and the aircraft may further include a fourth soundproof wall (50) that fills a gap (48) between the tank unit and the inner wall (12a) of the fuselage, connecting the cabin and the drive source. This reduces drive noise transmitted to the cabin through the gap by the fourth soundproof wall. [Explanation of symbols]

[0074] 10... Aircraft 12... Fuselage 12a...Inner wall of fuselage 28...Tank unit 30... Valve 32... Valve control section 34...Drive source 40...Fuel tank 42...Soundproof wall (first soundproof wall) 44...Soundproof wall (second soundproof wall) 46...Soundproof wall (third soundproof wall) 48...Gap 50...Soundproof wall (4th soundproof wall) DS...Driving noise FL…Fuel Ga...Aircraft center of gravity excluding tank unit and fuel Gb: Center of gravity of aircraft including fuel

Claims

1. An aircraft having a cabin for a crew member and a drive source that is driven using supplied fuel, a tank unit arranged between the cabin and the drive source and including a stack of multiple fuel tanks for storing the fuel; an aircraft, wherein the plurality of fuel tanks are independent of one another such that the fuel cannot be transferred from each of the plurality of fuel tanks to another of the fuel tanks;

2. 10. The aircraft of claim 1, The aircraft, wherein the plurality of fuel tanks are stacked in an arrangement direction of the cabin and the drive source.

3. An aircraft having a cabin for a crew member and a drive source driven by supplied fuel, a tank unit arranged between the cabin and the drive source and including a plurality of stacked fuel tanks for storing the fuel; a plurality of valves provided corresponding to the plurality of fuel tanks, respectively; a valve control unit that controls the amount of fuel supplied from the tank unit to the driving source by controlling opening and closing of the plurality of valves; Furthermore, When one of the fuel tanks becomes empty, the valve control unit supplies the fuel from another of the fuel tanks to the drive source.

4. 4. An aircraft according to claim 3, The valve control unit selects the fuel tank that supplies the fuel to the driving source in accordance with a predetermined order, and supplies the fuel from the selected fuel tank to the driving source.

5. 5. An aircraft according to claim 4, The predetermined order is determined so that the fuel in the fuel tank farthest from the center of gravity of the aircraft including the fuel is supplied to the drive source first.

6. An aircraft according to any one of claims 1 to 5, The tank unit is positioned on the center of gravity of the aircraft excluding the tank unit and the fuel.

7. An aircraft according to any one of claims 1 to 6, The aircraft further comprises a soundproof wall installed between the cabin and the tank unit.

8. An aircraft having a cabin for a crew member and a drive source driven by supplied fuel, a tank unit arranged between the cabin and the drive source and including a plurality of stacked fuel tanks for storing the fuel; a soundproof wall installed between the tank unit and the driving source; An aircraft comprising:

9. An aircraft having a cabin for a crew member and a drive source driven by supplied fuel, a tank unit arranged between the cabin and the drive source and including a plurality of stacked fuel tanks for storing the fuel; a soundproof wall installed between two adjacent fuel tanks; An aircraft comprising:

10. An aircraft having a cabin for a crew member and a drive source driven by supplied fuel, a tank unit arranged between the cabin and the drive source and including a stack of multiple fuel tanks for storing the fuel; the cabin, the drive source, and the tank unit are provided inside a fuselage of the aircraft, The aircraft further includes a soundproof wall that fills a gap between the tank unit and an inner wall of the fuselage, the gap connecting the cabin and the drive source.

11. An aircraft having a cabin for a crew member and a drive source driven by supplied fuel, a tank unit arranged between the cabin and the drive source and including a plurality of stacked fuel tanks for storing the fuel; a plurality of valves provided corresponding to the plurality of fuel tanks, respectively; Equipped with When one valve of the plurality of valves is opened, at least one valve of the remaining valves is closed.

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