JP2011105266A - Fuel tank for aircraft with explosion-proof function, and method of preventing explosion - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a fuel tank capable of reducing the amount of explosion-proof gas generated, maintaining an explosion preventing effect, by setting oxygen concentration in a gaseous phase inside of a fuel tank at a value below a predetermined value, and capable of miniaturizing an explosion-proof gas generating device. <P>SOLUTION: This fuel tank includes: a plurality of tanks respectively storing fuel and communicated with each other through communication holes; an explosion-proof gas generating device supplying explosion-proof gas including a predetermined concentration or more of inactive gas; and a gas supply pipe provided to pass through the inside of the plurality of tanks through the through holes so that the explosion-proof gas flows therein. An injection opening for injecting the explosion-proof gas is formed in a side surface of the gas supply pipe inside of each of the plurality of tanks. A sufficient quantity of the explosion-proof gas can be supplied, restricting the waste, by supplying the explosion-proof gas into the tank based on the fuel detected amount inside of each tank. <P>COPYRIGHT: (C)2011,JPO&INPIT

Description

  The present invention relates to an aircraft fuel tank structure, and more particularly to an aircraft fuel tank having an explosion-proof function.

  As one of the explosion-proof methods for the fuel tank, a technique for keeping the oxygen concentration of the gas in the fuel tank low is known. For example, Patent Document 1 describes a technique for supplying an inert gas into a fuel tank and scavenging a gas layer region in the fuel tank.

  FIG. 1 is given as a reference example of explosion-proof means. FIG. 1 is a schematic diagram showing the configuration of a part of a fuel tank 110 provided on the main wing of an aircraft. The main wing 130 is provided with a plurality of fuel tanks 111 (1), 111 (2), 111 (3). In each of the fuel tanks 111 (1) to 111 (3), a liquid phase region 112 in which a liquid phase fuel is stored is drawn. Above the liquid level of the fuel in each fuel tank is a gas phase region 102. The gas phase region 102 is supplied with an inert gas from an on-machine inert gas generator 114 through an inert gas supply pipe 113.

  Patent Document 2 and Patent Document 3 are given as examples of techniques for supplying gas into the wing of an aircraft.

JP 2003-127996 A Japanese Patent No. 3529910 Japanese Patent No. 3529911

  In the gas ejection method as in the above reference example, an inert gas for explosion prevention (hereinafter referred to as explosion-proof gas) is ejected in a certain amount in a certain direction. That is, even if the remaining amount of fuel in each fuel tank is different, the explosion-proof gas is supplied in the same manner. In such a method, even when the remaining amount of fuel is large, the explosion-proof gas is supplied in the same manner as when the amount of fuel is small, so that an unnecessarily large amount of explosion-proof gas may be consumed. As a result, a large amount of explosion-proof gas is required, and the gas generator has been enlarged.

  Therefore, an object of the present invention is to reduce the amount of explosion-proof gas generated while keeping the explosion-proof effect while keeping the oxygen concentration in the gas phase region, which is a region where no liquid-phase fuel is present in the fuel tank, at a predetermined value or less. An object of the present invention is to provide an aircraft fuel tank capable of downsizing a gas generator.

  Hereinafter, means for solving the problem will be described using the numbers and symbols used in the embodiments for carrying out the invention. These numbers and symbols are added with parentheses in order to clarify the correspondence between the description of the claims and the mode for carrying out the invention. However, these numbers and symbols should not be used for interpreting the technical scope of the invention described in the claims.

In order to solve the above-described problem, an aircraft fuel tank according to an aspect of the present invention stores a plurality of tanks (11 (1), 11 (11) each storing fuel (12) and communicating with each other via a communication hole (5a). 2) ..., 11 (n)), an explosion-proof gas generator (14) for supplying an explosion-proof gas containing an inert gas at a predetermined concentration or more, and a plurality of tanks (11 (1) through a communication hole (5a). ), 11 (2)... 11 (n)) and a gas supply pipe (13) through which explosion-proof gas flows. On the side surface of each of the plurality of tanks (11 (1), 11 (2)..., 11 (n)) of the gas supply pipe (13), an ejection port (16) from which explosion-proof gas is ejected is formed. .
The fuel tank further determines a generation amount of the explosion-proof gas based on a detection unit (15) that detects information on the amount of the fuel (12) in the tank (11), and a detection result of the detection unit (15), A control unit (18) for outputting an explosion-proof gas generation amount control signal indicating the generation amount to the explosion-proof gas generation device (14). The explosion-proof gas generator (14) generates explosion-proof gas based on the explosion-proof gas generation amount control signal and supplies it to the gas supply pipe (13).

According to the present invention, as compared with the case of FIG. 1, the piping is shortened and simplified, so that the explosion-proof gas can be efficiently and rapidly supplied to each fuel tank. Thereby, the usage-amount of explosion-proof gas can be reduced.
Further, according to the present invention, since the amount of explosion-proof gas generated is adjusted according to the detection result of the amount of fuel, the amount of explosion-proof gas generated can be reduced, and the capacity or size of the explosion-proof gas generator can be reduced. it can.

  According to still another aspect of the present invention, the fuel tank further communicates with the gas supply pipe (13), and an explosion portion (16) from which explosion-proof gas is ejected and an explosion-proof gas ejected from the ejection portion (16). And an adjustment mechanism (17) that makes it possible to adjust the ejection direction and the ejection amount. The control unit (18) determines the ejection direction and the ejection amount of the explosion-proof gas based on the detection result of the detection unit (15), and adjusts the gas ejection amount / direction control signal indicating the ejection direction and the ejection amount. To 17). The adjustment mechanism (17) adjusts the ejection amount and ejection direction of the explosion-proof gas in the ejection section (16) based on the gas ejection amount / direction control signal.

  According to the present invention, since the ejection direction and the ejection amount of the explosion-proof gas are determined based on the detected value of the fuel amount, the explosion-proof gas can be ejected to a necessary amount and a necessary place. Therefore, the amount of explosion-proof gas generated can be reduced, and the capacity or size of the explosion-proof gas generator can be reduced.

  In still another aspect of the present invention, the fuel tank further includes a concentration detector (not shown) that detects the gas concentration in the gas phase region (2) in the tank (11). The control unit (18) determines the generation amount of the explosion-proof gas based on the detection result of the concentration detection unit (not shown) in addition to the detection result of the detection unit (15), and the explosion-proof gas generation amount control signal is explosion-proof. It outputs to a gas generator (14).

  According to the present invention, the amount of explosion-proof gas generated is determined based on the detection result of the concentration detection unit in addition to the detection result of the detection unit. Therefore, when an explosion-proof gas is required, the required amount can be generated, the generation amount of the explosion-proof gas can be reduced, and the capacity or size of the explosion-proof gas generator can be reduced.

  In still another aspect of the present invention, the control unit (18) determines to close the ejection unit (16) when the detection unit (15) detects that the remaining amount of the fuel (12) is zero. Then, a gas ejection amount / direction control signal indicating that the ejection section (16) is closed is output to the adjustment mechanism (17). The adjustment mechanism (17) closes the ejection part (16) based on the gas ejection amount / direction control signal.

  According to the present invention, when it is detected that the remaining amount of fuel is zero, the explosion-proof gas ejection portion is closed. Therefore, the explosion-proof gas is not ejected to a place where it is not necessary, the generation amount of the explosion-proof gas can be reduced, and the capacity or size of the explosion-proof gas generator can be reduced.

  In still another aspect of the present invention, when the ejection portion (16) is closed because the remaining amount of the fuel (12) is zero, the control portion (18) detects the detection result of the concentration detection portion (not shown). And based on the detection result of the detection part (15), the generation amount of explosion-proof gas is determined, and the explosion-proof gas generation amount control signal which shows the said generation amount is output to an explosion-proof gas generator (14). The control unit (18) further determines the ejection direction and the ejection amount of the explosion-proof gas based on the detection result of the detection unit (15), and adjusts the gas ejection amount / direction control signal indicating the ejection direction and the ejection amount. Output to mechanism (17).

  According to the present invention, when the ejection portion is closed because the remaining amount of fuel is zero, the control portion determines the amount of explosion-proof gas generated based on the detection result of the concentration detection portion and the detection result of the detection portion. The explosion-proof gas generation amount control signal indicating the generation amount is output to the explosion-proof gas generator. The control unit further determines the ejection direction and the ejection amount of the explosion-proof gas based on the detection result of the detection unit, and outputs a gas ejection amount / direction control signal indicating the ejection direction and the ejection amount to the adjustment mechanism. Therefore, when explosion-proof gas is required, explosion-proof gas can be generated and ejected, the amount of explosion-proof gas generated can be reduced, and the capacity or size of the explosion-proof gas generator can be reduced. Can also be improved.

  In the explosion-proof method for an aircraft fuel tank according to one aspect of the present invention, a detection unit (15) provided in a tank (11) for storing fuel (12) detects information related to the amount of fuel (12). The step of sending the detection result as a fuel amount signal to the control unit (18), and the control unit (18), based on the fuel amount signal, the generation amount of the explosion-proof gas, the ejection amount of the explosion-proof gas, and the ejection direction of the explosion-proof gas. And a control unit (18) adjusts an explosion-proof gas generation amount control signal indicating the generation amount to an explosion-proof gas generation device (14) and a gas injection amount / direction control signal indicating the injection amount and the injection direction. The step of outputting to (17), the step of the explosion-proof gas generator (14) supplying the explosion-proof gas to the gas supply pipe (13) by the flow rate and the amount corresponding to the explosion-proof gas generation amount control signal, and the adjusting mechanism ( 17) An ejection part (16) in which an explosion-proof gas is ejected from an ejection part (16) communicating with the gas supply pipe (13) and ejecting an explosion-proof gas in an ejection amount and direction corresponding to the gas ejection amount / direction control signal. Adjusting. The explosion-proof gas supplied to the gas supply pipe (13) is supplied to the tank (11) from the ejection part (16) adjusted by the adjustment mechanism (17).

  According to the present invention, a detection unit provided in a tank for storing fuel detects information related to the amount of fuel, and sends the detection result to the control unit as a fuel amount signal. The step of determining the generation amount of explosion-proof gas, the explosion amount of explosion-proof gas and the ejection direction of explosion-proof gas based on the quantity signal, and the control unit sends an explosion-proof gas generation amount control signal indicating the generation amount to the explosion-proof gas generator, A step for outputting a gas ejection amount / direction control signal indicating the ejection amount and the ejection direction to the adjusting mechanism, and an explosion-proof gas generator supplying the explosion-proof gas to the gas supply pipe in a flow rate and an amount corresponding to the explosion-proof gas generation amount control signal. The supplying step and the adjusting mechanism are arranged so that the explosion-proof gas is ejected from the ejection part that communicates with the gas supply pipe and ejects the explosion-proof gas in the ejection amount and direction corresponding to the gas ejection amount / direction control signal. And a step of adjusting the part. Since the explosion-proof gas supplied to the gas supply pipe is supplied to the tank from the ejection part adjusted by the adjustment mechanism, the amount of explosion-proof gas generated is reduced by ejecting the explosion-proof gas to the required location. The capacity or size of the explosion-proof gas generator can be reduced.

  According to another aspect of the present invention, the explosion-proof method for an aircraft fuel tank further detects the gas concentration in the gas phase region (2), which is the region without the fuel (12) in the tank (11), and detects the gas concentration. The step of sending the result as a gas concentration signal to the control unit (18), the step of the control unit (18) determining the second generation amount of the explosion-proof gas based on the gas concentration signal, the generation amount and the second generation amount The step of setting the generated amount anew, whichever is larger, and the step of sending an explosion-proof gas generation amount control signal indicating the set generation amount to the explosion-proof gas generator (14) are further provided.

  According to the present invention, the step of detecting the gas concentration in the gas phase region, which is a region without fuel in the tank, and sending the detection result to the control unit as a gas concentration signal, and the control unit based on the gas concentration signal A step of determining the second generation amount of the explosion-proof gas, a step of setting the larger one of the generation amount and the second generation amount as the generation amount, and an explosion-proof gas generation amount control signal indicating the set generation amount. And a step of sending to the explosion-proof gas generator, so that when the explosion-proof gas is required depending on the gas concentration, the required amount can be generated, the generation amount of the explosion-proof gas is reduced, and the capacity or size of the explosion-proof gas generator is reduced. can do.

  According to the present invention, the oxygen concentration in the gas phase region, which is a region where no fuel exists in the fuel tank, is set to a predetermined value or less, the explosion-proof gas generation amount is reduced while maintaining the explosion-proof effect, and the explosion-proof gas generation device is downsized. An aircraft fuel tank and explosion-proof method are provided.

FIG. 1 is a schematic diagram showing a configuration of a part of a conventional fuel tank. FIG. 2 is a schematic diagram showing a configuration of a fuel tank according to an embodiment of the present invention. FIG. 3 is a schematic diagram illustrating an example of the configuration of the adjustment mechanism according to the embodiment of the present invention. FIG. 4A is a schematic diagram illustrating a difference in gas ejection angle and gas ejection amount depending on the remaining amount of fuel in the fuel tank according to the embodiment of the present invention. FIG. 4B is a schematic diagram illustrating a difference in gas ejection angle and gas ejection amount depending on the remaining amount of fuel in the fuel tank according to the embodiment of the present invention. FIG. 5 is a flowchart showing the operation of the fuel tank according to the embodiment of the present invention. FIG. 6 is an example of a calculation table stored in the control unit according to the embodiment of this invention.

  Embodiments of a fuel tank according to the present invention will be described below with reference to the accompanying drawings.

First, the configuration of a fuel tank according to an embodiment of the present invention will be described.
FIG. 2 is a schematic diagram showing the configuration of the fuel tank 10 according to the embodiment of the present invention. The aircraft fuel tank 10 is provided on the main wing 30. The fuel tank 10 is divided into a plurality of fuel tanks 11 (1), 11 (2), 11 (3),..., 11 (n) (n is a positive integer) by the rib 5. However, since the communication hole 5a through which the explosion-proof gas supply pipe 13 passes is opened in the rib 5, the fuel 12 can flow from there. Since the basic structure of the fuel tanks 11 (1), 11 (2), 11 (3),..., 11 (n) is the same, hereinafter, unless particularly required to be distinguished, The fuel tank 11 will be described.

  Each fuel tank 11 stores fuel 12 supplied from a fuel pipe (not shown). The stored fuel 12 is supplied to an engine or the like via another fuel pipe (not shown). Each fuel tank 11 has a detector 15. The detection unit 15 is a fuel amount sensor, detects the remaining amount (the level of the liquid level) of the fuel 12 in the fuel tank 11, and sends the detection result to the control unit 18 as a fuel amount signal. The control unit 18 is an explosion-proof controller, and is based on the fuel amount signal received from the detection unit 15 and a calculation formula or table stored in the control unit 18, and the amount of explosion-proof gas generated, the amount of explosion-proof gas jetted, and Determine the explosion direction of the explosion-proof gas. Then, an explosion-proof gas generation control signal 18-2 indicating the generation amount of the explosion-proof gas is supplied to the explosion-proof gas generator 14, and a gas injection amount / direction control signal 18-3 indicating the injection amount and direction of the explosion-proof gas is adjusted to the adjustment mechanism 17. Send to each.

  The explosion-proof gas generator 14 generates explosion-proof gas. The generated explosion-proof gas is sent to the gas supply pipe 13 via the valve 14-1. The control unit 18 adjusts the total amount of explosion-proof gas sent to the gas supply pipe 13 by controlling the opening degree of the valve 14-1. The explosion-proof gas is a gas containing a large amount (in a predetermined concentration or more) of an inert gas exemplified as a rare gas. As the explosion-proof gas, an inert gas itself having an inert gas concentration of 100% can be used. Alternatively, as an explosion-proof gas, the proportion of an inert gas such as nitrogen is increased, the proportion of oxygen is reduced compared to air, and the oxygen concentration is below the explosion limit of the fuel 12 (example: inert gas concentration of 91% or more). ) Can be used.

  A gas supply pipe 13 is disposed inside the fuel tank 10. The gas supply pipe 13 is introduced into the first fuel tank 11 (1) at the connection portion 9. The gas supply pipe 13 further passes through a hole communicating with an adjacent fuel tank among the plurality of fuel tanks 11 (1), 11 (2), 11 (3),. It is introduced into the tanks 11 (2), 11 (3), ..., 11 (n). In this way, the gas supply pipe 13 is provided so as to penetrate the inside of the plurality of tanks 11 (1), 11 (2), 11 (3),..., 11 (n) through the communication hole 5a. It is done. The gas supply pipe 13 is a kind of piccolo tube. That is, it is a tube having openings on the side surfaces at various positions in the extending direction. However, unlike typical piccolo tubes, their openings are not formed at various fixed positions in the circumferential direction of the tube.

  The side surface of the gas supply pipe 13 has at least one ejection portion 16 in each fuel tank 11. The gas supply pipe 13 supplies the explosion-proof gas generated by the explosion-proof gas generator 14 to each fuel tank 11 by ejecting the explosion-proof gas from the ejection portion 16 into each fuel tank 11. In consideration of the explosion-proof structure, the gas supply pipe 13 is preferably formed of a highly conductive aluminum or carbon composite tube. The gas supply pipe 13 may have any shape as long as the explosion-proof gas can pass through. However, in order to make it possible to control the ejection amount and the ejection angle of the explosion-proof gas as described later, it is easiest to use a tube having a circular cross section. Further, the gas supply pipe 13 may be a single pipe or a plurality of pipes joined together.

  The adjustment mechanism 17 is provided near the outside of the fuel tank 11 in consideration of explosion prevention. The adjustment mechanism 17 is an ejection amount / direction control actuator, and controls the area and direction of the opening region of the ejection portion 16 based on the gas ejection amount / direction control signal 18-3 from the control portion 18. The adjusting mechanism 17 controls the ejection portion 16 to control the gas ejection amount and the gas ejection direction of the explosion-proof gas that is injected into each fuel tank 11.

  FIG. 3 is a schematic diagram showing an example of the configuration of the adjusting mechanism 17 according to the embodiment of the present invention. The ejection part 16 is a member having an opening region from which explosion-proof gas can be ejected. The ejection part 16 adjusts the ejection amount and the ejection direction of the explosion-proof gas generated by the explosion-proof gas generator 14 and supplied via the gas supply pipe 13. The ejection part 16 includes a rotation cover 22 and a rotation tube 23 as a mechanism for the adjustment. The rotating cover 22 and the rotating tube 23 have a coaxial cylindrical shape, and one cylinder includes the other cylinder. In this example, the rotation cover 22 includes the rotation tube 23 and is disposed outside the rotation tube 23. The rotating cover 22 and the rotating tube 23 can slide in the circumferential direction. The rotating tube 23 is connected to the gas supply pipe 13 at the connection portion 24. The connection portion 24 is a slip ring that connects the gas supply pipe 13 and the rotary tube 23 so as to be rotatable in the circumferential direction.

  The rotary cover 22 has an opening 25 in which the width in the longitudinal direction of the tube monotonously increases in the range from the first angle to the second angle in the circumferential direction of the tube. In FIG. 3, as a preferable example, a triangular opening 25 arranged so that one side faces the longitudinal direction of the tube is depicted. The rotating tube 23 has an opening 26 that is a rectangular slit whose longitudinal width is equal to or larger than the maximum width of the opening 25 and whose circumferential length is smaller than the width.

  A region where the opening 25 and the opening 26 overlap is an opening region (through hole) through which the explosion-proof gas flowing through the gas supply pipe 13 is ejected to the outside. At this time, the gas ejection angle and the gas ejection amount are adjusted by rotating the rotation cover 22 and the rotation tube 23 at independently controlled rotation angles. The gas ejection angle is determined by controlling the position of the opening 26 in the circumferential direction of the tube. The ratio of the gas ejection amount of each fuel tank 11 is determined by the area (valve opening) of the opening region corresponding to the degree of overlap between the opening 25 and the opening 26 in each fuel tank 11.

  The adjusting mechanism 17 is a driving mechanism including motors 19a and 19b, rotating members 20a and 20b as transmission mechanisms, and connecting cables 21a and 21b. The rotary cover 22 is connected to the connecting cable 21a. The connecting cable 21a is connected to the rotating member 20a. The rotating member 20a is connected to the motor 19a.

  The motor 19 a operates the rotating member 20 a based on the ejection amount / direction control signal from the control unit 18. The rotation of the rotary member 20a is transmitted by the connecting cable 21a, so that the rotary cover 22 rotates. Similarly, the rotating tube 23 is connected to the connecting cable 21b. The connecting line 21b is connected to the rotating member 20b. The rotating member 20b is connected to the motor 19b. The motor 19b operates the rotating member 20b based on the ejection amount / direction control signal from the control unit 18. The rotation of the rotary member 20b is transmitted by the connecting cable 21b, whereby the rotary cover 22 rotates. Since the adjusting mechanism 17 includes the motors 19a and 19b and the rotating members 20a and 20b, it is preferable to install the adjusting mechanism 17 outside the fuel tank 10 in consideration of explosion prevention.

  FIG. 4A and FIG. 4B are schematic diagrams illustrating the difference in the explosion-proof gas ejection angle and the gas ejection amount depending on the remaining amount of fuel in the fuel tank according to the embodiment of the present invention. FIG. 4A shows a case where the remaining amount of the fuel 12 is large and the gas phase region 2 is small. FIG. 4B shows a case where the remaining amount of the fuel 12 is small and the gas phase region 2 is large.

  As shown in FIG. 4A, the ejection angle of the explosion-proof gas when the remaining amount of the fuel 12 is large is θ1, and the ejection amount of the explosion-proof gas is Q1. As shown in FIG. 4B, the explosion angle of the explosion-proof gas when the remaining amount of the fuel 12 is small is θ2, and the ejection amount of the explosion-proof gas is Q2. θ1 and θ2 are defined by the depression angle from the horizontal plane assuming that the aircraft is flying substantially horizontally.

  θ1 and θ2 are set in a direction toward the farthest part from the ejection part 16 in the gas phase region 2 (the part where the rib 5 far from the explosion-proof machine body supply pipe 13 and the liquid level of the fuel 12 intersect). At this time, the ejection portion 16 is adjusted so that θ1 <θ2 and Q1 <Q2. This is because the smaller the remaining amount of the fuel 12, the more the gas phase region 2 increases, and it is necessary to supply more explosion-proof gas in order to lower the oxygen concentration in the gas phase region 2. By supplying as much explosion-proof gas as possible in the gas phase region 2 as far as possible, the oxygen concentration in the gas phase region 2 can be maintained at a low value.

  In FIG. 4A and FIG. 4B, for easy understanding, the explosion-proof gas ejection angle and the gas ejection amount are schematically shown in a two-dimensional direction. However, the present invention is not limited to this example, and the direction can be set three-dimensionally. Further, in FIG. 4A and FIG. 4B, when the gas supply pipe 13 is near the upper center of the gas phase region 2, at least two ejection parts 16 are provided in the fuel tank 11. The explosion-proof gas may be ejected in the downward direction and the lower left direction. In this case, the explosion-proof gas can be further rapidly supplied, and the oxygen concentration in the gas phase region 2 can be lowered more quickly.

  As described above, by appropriately controlling the ejection amount and the ejection direction of the explosion-proof gas in accordance with the amount of the gas phase region 2, it is possible to eject the explosion-proof gas to a necessary portion as much as necessary. That is, the explosion-proof gas can be efficiently ejected without waste. As a result, the explosion-proof gas ejection amount when the remaining amount of the fuel 12 is large can be reduced, and the explosion-proof gas ejection amount can be suppressed while maintaining the explosion-proof property.

Next, the operation of the fuel tank according to the embodiment of the present invention (fuel tank explosion-proof method) will be described. FIG. 5 is a flowchart showing the operation of the fuel tank (method for explosion-proofing the fuel tank) according to the embodiment of the present invention.
First, in the fuel tank 11, the detection unit 15 constantly detects and monitors the remaining amount of the fuel 12. The detection result is transmitted to the control unit 18 as a fuel amount signal (step S01).

  The control unit 18 monitors whether or not a predetermined condition is satisfied. The predetermined condition is, for example, that the remaining amount of the fuel 12 in at least one fuel tank 11 is equal to or less than a predetermined set value, or that a preset time interval has elapsed. The control unit 18 performs the following operation when a predetermined condition is satisfied. The control unit 18 uses the received fuel amount signal to determine the necessary amount of explosion-proof gas generated, the amount of explosion-proof gas jetted, and the direction of explosion-proof gas jetting according to a calculation formula or table stored in the control unit 18. Then, an explosion-proof gas generation control signal 18-2 indicating the generation amount of the explosion-proof gas is supplied to the explosion-proof gas generator 14, and a gas injection amount / direction control signal 18-3 indicating the injection amount and direction of the explosion-proof gas is adjusted to the adjustment mechanism 17. (Step S02).

  The adjustment mechanism 17 drives the motor 19a in accordance with the received gas ejection amount / direction control signal 18-3, and rotates the rotary cover 22 of the ejection portion 16 via the rotating member 20a and the connecting line 21a. The adjusting mechanism 17 further drives the motor 19b to rotate the rotating tube 23 of the ejection portion 16 via the rotating member 20b and the connecting cable 21b. In this way, the gas ejection angle is adjusted by the rotational position of the opening 26, and the gas ejection amount is adjusted by changing the overlapping degree of the opening 25 and the opening 26 (step S03). In accordance with the received explosion-proof gas generation amount control signal 18-2, the explosion-proof gas generator 14 supplies a predetermined amount of explosion-proof gas to the gas supply pipe 13 at a predetermined flow rate (step S04).

  The explosion-proof gas supplied to the gas supply pipe 13 is supplied to the fuel tank 11 in the fuel tank 10 from the ejection portion 16 adjusted by the adjustment mechanism 17 (step S05).

  FIG. 6 is an example of a calculation formula or a table stored in the storage device of the control unit 18. This table shows the remaining amount P of the fuel 12, the ejection direction θ of the explosion-proof gas, the area S of the opening region, the ejection amount Q of the explosion-proof gas, the rotation angle δa of the rotating tube 23, the rotating tube 23 and the rotating cover. 22 and the relative displacement angle δb. However, 0 <P2 <P1, θ1 <θ2 <θ3, S1 <S2 <S3, Q1 <Q2 <Q3, δa1 <δa2 <δa3, and δb1 <δb2 <δb3. The rotation angle δa is based on, for example, a position farthest from the surface of the stationary fuel 12 in the gas supply pipe 13. For example, the relative displacement angle δb is based on the position where the area S is the smallest when the area S of the opening region monotonously increases.

  The control unit 18 extracts a value corresponding to the detected remaining fuel amount P in the table as shown in FIG. 6, so that the ejection direction θ, the area S, the ejection amount Q, the rotation angle δa, The relative displacement angle δb can be calculated. Alternatively, the control unit 18 can calculate these values using a predetermined calculation formula. For example, first, when the fuel 12 has a certain remaining amount P, the necessary explosion-proof gas ejection direction θ and the necessary explosion-proof gas ejection amount Q are obtained based on the remaining amount P. Next, the opening direction of the opening 26, that is, the rotation angle δa of the rotating tube 23 is obtained based on the necessary explosion-proof gas ejection direction θ. Further, based on the required gas ejection amount Q, the relative displacement angle δb between the rotating tube 23 and the rotating cover 22 is obtained from the degree of overlap between the opening 25 and the opening 26, that is, the required area S of the opening region. .

  Therefore, in order to control the ejection amount and the ejection direction of the explosion-proof gas, the control unit 18 rotates the rotating tube by δa based on the obtained δa and δb, and at the same time commands to rotate the rotating cover by δa + δb. A direction control signal 18-3 is sent to the adjusting mechanism 17. Thereby, the opening direction of the opening part 26 and the overlapping degree of the opening part 25 and the opening part 26 are adjusted, and the necessary explosion-proof gas ejection direction and the ejection amount are realized.

  Furthermore, since the fuel tank 10 of an aircraft normally has a pressure difference between the inside and outside of the fuel tank 10 when an air pressure fluctuation occurs due to the rising or lowering of the aircraft, it is necessary to release the inside air or take in outside air. In that case, the concentration of the explosion-proof gas or the oxygen concentration in the gas phase region 2 in the fuel tank 11 varies greatly. Therefore, it is necessary to supply explosion-proof gas to the fuel tank 11 corresponding to the fluctuations in the concentration. Therefore, in addition to the fuel amount signal from the detection unit 15, the control unit 18 receives an explosion-proof gas in the gas phase region 2 of the fuel tank 11 from an explosion-proof gas concentration sensor (not shown) or an oxygen concentration sensor (not shown). Or a gas concentration signal indicative of the concentration of oxygen. It is also possible to control the explosion-proof gas generator 14 based on the gas concentration signal and supply the explosion-proof gas into the fuel tank 10.

  In that case, the following modifications can be considered as the operation of the fuel tank (fuel tank explosion-proof method) according to the embodiment of the present invention. First, an explosion-proof gas concentration sensor (not shown) or an oxygen concentration sensor (not shown) detects the explosion-proof gas concentration or oxygen concentration in the gas phase region 2. And a detection result is sent to the control part 18 as a gas concentration signal (gas concentration detection step). The control unit 18 uses the received gas concentration signal to determine the amount of generation based on the required gas concentration of the explosion-proof gas using another calculation formula or other table stored in the control unit 18. On the other hand, the control unit 18 uses the fuel amount signal received from the detection unit 15 based on the required fuel amount of the explosion-proof gas by the calculation formula or table stored in the control unit 18 as in step S02. Determine the generation amount, the amount of explosion-proof gas and the direction of explosion-proof gas. Then, the generation amount based on the gas concentration of the explosion-proof gas is compared with the generation amount based on the fuel amount of the explosion-proof gas, and the one with the larger generation amount is finally determined as the generation amount of the explosion-proof gas. After that, an explosion-proof gas generation amount control signal 18-2 indicating the finally determined amount of explosion-proof gas is sent to the explosion-proof gas generator 14, and the amount and direction control of the gas indicating the amount and direction of the explosion-proof gas. Each of the signals 18-3 is transmitted to the adjustment mechanism 17 (determination of density adjustment amount). Thereafter, the explosion-proof gas is supplied to the fuel tank 11 by performing the above-described steps S03 to S05.

  However, the density adjustment amount determination step may be as follows. The control unit 18 uses the received gas concentration signal and the fuel amount signal of the detection unit 15 to generate the necessary amount of explosion-proof gas by using another calculation formula or further table stored in the control unit 18. The amount of explosion-proof gas and the direction of explosion-proof gas are determined. Then, the explosion-proof gas generation amount control signal 18-2 indicating the generation amount of the explosion-proof gas is adjusted to the explosion-proof gas generation device 14, and the gas injection amount / direction control signal 18-3 indicating the injection amount and the injection direction of the explosion-proof gas is adjusted. Each is transmitted to the mechanism 17.

  By such control, it is possible to cope with a case where the explosion-proof gas concentration is lowered or the oxygen concentration is raised due to the release of the inside air due to the difference between the inside and outside pressures of the fuel tank 10 or the intake of the outside air. The control unit 18 controls the explosion-proof gas generator 14 to generate a necessary amount of explosion-proof gas. The control unit 18 further controls the ejection unit 16 according to the remaining amount of the fuel 12 of the detection unit 15 described above. As a result, a necessary amount of explosion-proof gas can be supplied to a necessary place, and the explosion-proof gas ejection amount can be suppressed while maintaining the explosion-proof property.

  In addition, a gas concentration signal in the gas phase region 2 from an explosion-proof gas concentration sensor (not shown) or an oxygen concentration sensor (not shown) can also be used to determine the amount of explosion-proof gas generated. Such control is effective when internal air discharge or external air intake occurs due to the internal / external pressure difference of the fuel tank 10. Such control is also effective in the case where the oxygen concentration in the gas phase region 2 rises due to the gas containing a large amount of oxygen dissolved in the fuel 12 coming out to the gas phase region 2. .

  Further, when the remaining amount of one fuel 12 in the fuel tank 11 is zero, the following modifications can be considered as the operation of the fuel tank (explosion-proof method of the fuel tank) according to the embodiment of the present invention. First, the detection unit 15 of a certain fuel tank 11 sends a fuel amount signal that the remaining amount of the fuel 12 is zero to the control unit 18. The control unit 18 substitutes the value of the received fuel amount signal that the remaining amount of the fuel 12 is zero into the conditional expression (or calculation formula or table) stored in the control unit 18. As a result, an ejection amount / direction signal instructing to close the ejection portion 16 of the fuel tank 11 is obtained. The control unit sends this ejection amount / direction signal to the adjusting mechanism 17. The adjustment mechanism 17 of the fuel tank 11 closes the ejection part 16 based on the received ejection amount / direction signal, and stops the ejection of the explosion-proof gas.

  When the fuel 12 is zero, the explosion-proof gas is stopped from being ejected, so that it is possible to avoid supplying the explosion-proof gas to an unnecessary place. As a result, the explosion-proof gas ejection amount can be suppressed while maintaining the explosion-proof property.

  However, even when the ejection portion 16 is closed, the concentration indicated by the gas concentration signal of the gas phase region 2 from the explosion-proof gas concentration sensor (not shown) or the oxygen concentration sensor (not shown) is not an appropriate value ( (Example: When the concentration of the explosion-proof gas is lower than the set value or the oxygen concentration is higher than the set value), the following operation may be performed. That is, as in the above-described operation method, the control unit 18 controls the explosion-proof gas generation device 14 based on the gas concentration signal or / and the fuel amount signal, so that the farthest part from the ejection unit 16 in the gas phase region 2. You may make it send the signal which adjusts the ejection part 16 to the adjustment mechanism 17 so that explosion-proof gas is ejected in the direction to go.

  Thus, even when the fuel 12 in a certain fuel tank 11 is zero and the generation and ejection of the explosion-proof gas are stopped, the explosion-proof gas can be supplied if necessary. As a result, the explosion-proof gas ejection amount can be suppressed while maintaining the explosion-proof property.

  As described above, according to the fuel tank 10 of the present embodiment, the adjustment mechanism 17 that can adjust the explosion-proof gas ejection direction and the explosion-proof gas ejection amount according to the remaining amount of the fuel 12 in each fuel tank 11 is provided. Therefore, the ejection direction and the ejection amount of the explosion-proof gas can be adjusted. Therefore, the explosion-proof gas can be ejected more efficiently, the generation amount of the explosion-proof gas can be reduced, and the capacity or size of the explosion-proof gas generation device can be reduced.

  In addition, this invention is not limited to the invention concerning the said embodiment, In the range which does not deviate from the summary, it can change suitably. For example, fuel consumption can be used instead of the remaining amount of fuel. In that case, a method of executing the above operation after calculating the remaining amount using the relationship (remaining amount of fuel = initial amount of fuel−fuel consumption), or a table of the control unit 18 is used for fuel consumption instead of remaining amount of fuel. A method of performing the above operation using a table based on the quantity is conceivable. At that time, as the detection unit, a device (for example, a flow meter, a flow rate integrating meter, or the like) that is provided in the fuel tank 11 and measures the amount of fuel (fuel consumption) supplied to the engine can be used. Moreover, when only a gas supply pipe rotates or only a rotation cover rotates, it can apply to what uses a valve for an ejection part, or what combined these.

  Moreover, although an opening part is provided as a gas supply pipe, it is also possible to use the piccolo tube which does not adjust the quantity and direction of an opening like the said ejection part. At this time, the ejection amount of the explosion-proof gas may not be controlled, or the control unit 18 may control only the amount of explosion-proof gas generated by the explosion-proof gas generator 14 based on the remaining amount of the fuel 12. In this case, as compared with the case of FIG. 1, the piping is shortened and simplified, so that the explosion-proof gas can be efficiently and rapidly supplied to the fuel tank 11. Furthermore, by providing a plurality of openings and making these directions various directions, the explosion-proof gas is efficiently supplied to the gas phase region as compared with the supply port in which the direction as shown in FIG. 1 is fixed. I can do it. Furthermore, the above-described modifications can be made. Further, the case where the fuel tank 10 is divided into a plurality of fuel tanks 11 (1) to 11 (n) has been described as an example, but the same effect can be obtained also in the case of a fuel tank of a single section.

2 Gas phase region 5 Rib 5a Communication hole 9 Connection portion 10 Fuel tank 11 (1), 11 (2), 11 (3), 11 (4) Fuel tank 12 Fuel 13 Explosion-proof gas supply pipe 14 Explosion-proof gas generator 14- DESCRIPTION OF SYMBOLS 1 Valve 15 Detection part 16 Ejection part 17 Adjustment mechanism 18 Control part 18-2 Explosion-proof gas generation amount control signal 18-3 Gas ejection amount and direction control signal 19 Motor 20 Rotating member 21 Connecting cable 22 Rotating cover 23 Rotating tube 24 Connection part 25 opening 26 opening 30 main wing 102 gas phase region 110 fuel tank 111 (1), 111 (2), 111 (3) fuel tank 112 fuel 113 inert gas supply pipe 114 on-machine inert gas generator 130 main wing

Claims (7)

A plurality of tanks each storing fuel and communicating with each other through a communication hole;
An explosion-proof gas generator for supplying an explosion-proof gas containing an inert gas at a predetermined concentration or more;
A gas supply pipe that is provided so as to penetrate the inside of the plurality of tanks through the communication hole, and through which the explosion-proof gas flows;
On the side surface of each of the plurality of tanks of the gas supply pipe, a spout is formed through which the explosion-proof gas is spouted,
A detector for detecting information on the amount of the fuel in the tank;
Based on the detection result of the detection unit, determining the generation amount of the explosion-proof gas, comprising a control unit for outputting an explosion-proof gas generation amount control signal indicating the generation amount to the explosion-proof gas generation device,
The explosion-proof gas generating device generates the explosion-proof gas based on the explosion-proof gas generation amount control signal and supplies the explosion-proof gas to the gas supply pipe. The aircraft fuel tank according to claim 1,
An ejection part that communicates with the gas supply pipe and from which the explosion-proof gas is ejected;
An adjustment mechanism that enables adjustment of the ejection direction and the ejection amount of the explosion-proof gas ejected from the ejection section;
The control unit further determines an ejection direction and an ejection amount of the explosion-proof gas based on a detection result of the detection unit, and sends a gas ejection amount / direction control signal indicating the ejection direction and the ejection amount to the adjustment mechanism. Output,
The adjustment mechanism adjusts an ejection amount and an ejection direction of the explosion-proof gas at the ejection portion based on the gas ejection amount / direction control signal. The aircraft fuel tank according to claim 2,
A concentration detector for detecting the gas concentration in the gas phase region in the tank;
The control unit determines the generation amount of the explosion-proof gas based on the detection result of the concentration detection unit in addition to the detection result of the detection unit, and outputs the explosion-proof gas generation amount control signal to the explosion-proof gas generation device Aircraft fuel tank. The aircraft fuel tank according to claim 2 or 3,
The said control part determines that the said ejection part is closed when the said detection part detects that the residual amount of the said fuel is zero, The said gas ejection amount and direction control signal which shows closing the said ejection part To the adjustment mechanism,
The adjustment mechanism closes the ejection portion based on the gas ejection amount / direction control signal. The aircraft fuel tank according to claim 4.
When the ejection portion is closed as the remaining amount of fuel is zero,
The control unit determines the generation amount of the explosion-proof gas based on the detection result of the concentration detection unit and the detection result of the detection unit, and sends an explosion-proof gas generation amount control signal indicating the generation amount to the explosion-proof gas generation device. Output,
The control unit further determines an ejection direction and an ejection amount of the explosion-proof gas based on a detection result of the detection unit, and sends a gas ejection amount / direction control signal indicating the ejection direction and the ejection amount to the adjustment mechanism. Output Aircraft fuel tank. A detection unit provided in a tank for storing fuel detects information on the amount of the fuel, and sends the detection result to the control unit as a fuel amount signal;
The control unit, based on the fuel amount signal, determining the generation amount of explosion-proof gas, the ejection amount of explosion-proof gas and the ejection direction of explosion-proof gas;
The control unit outputs an explosion-proof gas generation amount control signal indicating the generation amount to an explosion-proof gas generation device, and outputs a gas injection amount / direction control signal indicating the injection amount and the injection direction to an adjustment mechanism, respectively.
Supplying the explosion-proof gas of a flow rate and an amount corresponding to the explosion-proof gas generation amount control signal to a gas supply pipe;
The jetting is performed so that the explosion-proof gas is jetted from a jetting part through which the adjusting mechanism communicates with the gas supply pipe and jets the explosion-proof gas at a jetting amount and direction corresponding to the gas jetting amount / direction control signal. Adjusting the part, and
The explosion-proof gas supplied to the gas supply pipe is supplied to the tank from the ejection part adjusted by the adjustment mechanism. The method for explosion-proofing an aircraft fuel tank according to claim 6.
Detecting the gas concentration in the gas phase region, which is a region without fuel in the tank, and sending the detection result to the control unit as a gas concentration signal;
The controller determines a second generation amount of the explosion-proof gas based on the gas concentration signal;
Setting the larger one of the generated amount and the second generated amount as the generated amount;
An explosion-proof gas generation control signal indicating the set generation amount is further transmitted to the explosion-proof gas generation device.

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