Delivery hatch assembly and delivery hatch control method

Abstract

The present invention relates to a drop hatch assembly and a drop hatch control method. The drop hatch assembly includes: a first drop hatch, the first drop hatch including a first drop hatch pivot at a first side edge and pivotally connected to a fuselage of a firefighting aircraft via the first drop hatch pivot, the first drop hatch blocking a fire extinguishing medium outlet of the fuselage, and including a first door locking hook; a first lift actuator, the first lift actuator being connected to the fuselage and the first drop hatch from the outside of the aircraft, respectively, and actuating the first drop hatch to pivot about the first drop hatch pivot; a first latch shaft, the first latch shaft being rotatably disposed on the fuselage with its rotation center coaxial with the first door locking hook, the first latch shaft including a first latch portion cooperating with the first door locking hook, the first latch portion and the first door locking hook being engaged and disengaged by rotation of the first latch shaft; and a first latch actuator actuating the first latch shaft to rotate.

Description

Technical Field

[0001] The present invention relates to a release hatch assembly, specifically a release hatch assembly for a firefighting aircraft, which can be configured to release firefighting equipment from the air to the ground. The present invention also relates to a release hatch control method, which can enable the opening and closing of the release hatch for a firefighting aircraft to release firefighting equipment to the ground. This invention belongs to the field of firefighting aircraft release control design. Background Art

[0002] The research and application of existing firefighting aircraft in forest aerial firefighting are relatively mature. Helicopters and seaplanes are mainly used as firefighting aircraft. The main firefighting plan is to drop water bombs, water bags and other methods into the forest to extinguish the fire.

[0003] In recent years, more types of firefighting aircraft have been developed and deployed, such as light multi-purpose fixed-wing aircraft, large strategic transport aircraft, etc. At present, attempts are being made to convert regional passenger aircraft into firefighting aircraft.

[0004] The release hatch actuation control system is a crucial component of firefighting aircraft missions, and its reliability directly impacts the success of these missions. Fixed-wing aircraft, due to their high flight speeds, require the release hatch to open quickly to ensure the release of extinguishing media. Summary of the Invention

[0005] The purpose of the present invention is to provide a launch hatch device that can quickly open the launch hatch, has a simple structure, is easy to modify, requires little space, and minimizes the risk of interference with the launched fire extinguishing medium.

[0006] In response to the above-mentioned problems in the prior art, the inventors provide a delivery hatch assembly that can quickly open the delivery hatch to deliver the fire extinguishing medium and avoid interference with the release of the fire extinguishing medium.

[0007] In a first example of the delivery door assembly, the delivery door assembly includes: a first delivery door, the first delivery door includes a first delivery door pivot at a first side edge, and is pivotally connected to the fuselage of the fire-fighting aircraft through the first delivery door pivot, the first delivery door blocks the fire-extinguishing medium outlet of the fuselage, and the first delivery door includes a first door locking hook; a first lifting actuator, the first lifting actuator is respectively connected to the fuselage and the first delivery door from the outside of the aircraft, and actuates the first delivery door to pivot around the first delivery door pivot; a first latch shaft, the first latch shaft is rotatably provided on the fuselage and the rotation center is coaxial with the first door locking hook, the first latch shaft includes a first latch portion that cooperates with the first door locking hook, the first latch portion and the first door locking hook are engaged and disengaged by rotation of the first latch shaft; and a first latch actuator, the first latch actuator actuates the first latch shaft to rotate.

[0008] In a second example of the launch door assembly, optionally including the first example, a first end of the first lift actuator is connected to the fuselage from outside the aircraft near the first side edge, and a second end of the first lift actuator is connected to the middle section of the first launch door from outside the aircraft.

[0009] In a third example of the launch door assembly, which optionally includes one or more of the first and second examples, the launch door assembly further includes: a second launch door, the first launch door and the second launch door are arranged in a mirror-symmetrical manner relative to the center line of the fuselage in the span direction of the aircraft, and together block the fire extinguishing medium outlet, the second launch door includes a second door locking hook; a second lifting actuator, the second lifting actuator is connected to the fuselage and the second launch door at both ends, and actuates the second launch door to pivot between an open position and a closed position; a second latch shaft, the second latch shaft is rotatably provided on the fuselage and the rotation center is coaxial with the second door locking hook, the second latch shaft includes a second latch portion that cooperates with the second door locking hook, the second latch portion and the second door locking hook are engaged and disengaged by rotation of the second latch shaft; and a second latch actuator, the second latch actuator actuates the second latch shaft to rotate.

[0010] In a fourth example of the launch door assembly, which optionally includes one or more of the first to third examples, the first latch actuator and the second latch actuator are arranged on the same side of the fuselage in the span direction of the aircraft.

[0011] In a fifth example of the delivery door assembly, one or more of the first to fourth examples may be optionally included, and the delivery door assembly further comprises: a door target, the door target being located on a fourth side of the first delivery door adjacent to the first side; and a door-closed position proximity switch, the door-closed position proximity switch being located on the fuselage, close to the fourth side, and configured so that when the first delivery door is in the closed standby position, the door-closed position proximity switch can sense the door target.

[0012] In a sixth example of the launch hatch assembly, one or more of the first to fifth examples may be optionally included, and the launch hatch assembly further comprises: a latch shaft target, the latch shaft target being provided at a predetermined position on the outer circumferential surface of the first latch shaft; a latch position proximity switch, the latch position proximity switch being provided on the fuselage, being provided close to the outer circumferential surface of the first latch shaft, and being provided so that when the first latch shaft is in the latched position, the latch position proximity switch can sense the latch shaft target; and an unlatched position proximity switch, the unlatched position proximity switch being provided on the fuselage, being provided close to the outer circumferential surface of the first latch shaft, and being provided so that when the first latch shaft is in the unlatched position, the unlatched position proximity switch can sense the latch shaft target.

[0013] In a seventh example of the launch hatch assembly, optionally including one or more of the first to sixth examples, the first lift actuator and the first latch actuator are electric actuation mechanisms that do not include a hydraulic system.

[0014] The present invention provides a delivery hatch control method for a fire-fighting aircraft, wherein the delivery hatch control method includes the following steps when opening the delivery hatch: a first latch actuator actuates a first latch shaft to an unlatched position; the first delivery hatch opens and delivers the fire-extinguishing medium under the action of the gravity of the fire-extinguishing medium; wherein, when the delivery rate of the fire-extinguishing medium under the action of gravity alone meets a preset delivery requirement, the first lifting actuator follows, and wherein, when the delivery rate of the fire-extinguishing medium under the action of gravity alone does not meet the preset delivery requirement, the first lifting actuator actuates the first delivery hatch to move toward an open position; when the first delivery hatch reaches the open position, the first lifting actuator actuates and resists the movement trend of the first delivery hatch; and when the first delivery hatch is opened to a preset maximum opening angle, the first lifting actuator locks and maintains the current position of the first delivery hatch.

[0015] The present invention provides a delivery hatch control method for a fire-fighting aircraft, wherein the delivery hatch control method comprises the following steps when closing the delivery hatch: a first lifting actuator unlocks and actuates the first delivery hatch to a closed preparation position; the first lifting actuator locks and maintains the current position of the first delivery hatch; a first latch actuator actuates a first latch shaft to an upper latch position, and when the first latch shaft reaches the upper latch position, the first latch actuator stops actuating; the first lifting actuator is unlocked and structural deformation stress is released.

[0016] In another aspect of the launch hatch control method, in the step of the first latch actuator actuating the first latch shaft to the latched position, the launch hatch control method further includes: the first latch shaft rotates from the unlatched position toward the latched position, the first latch portion of the first latch shaft contacts the first door locking hook portion of the first launch hatch, the first latch shaft continues to rotate so that the first launch hatch pivots from the closed preparatory position toward the closed position, and the first latch actuator actuates the first latch shaft to rotate to the latched position.

[0017] This patent provides a control system and method for the launch door of a fire-fighting aircraft. By externally placing the actuator, the resistance to the launch of the fire-fighting medium is reduced; the launch door opening method that combines gravity launch with active control improves the door opening efficiency; and the door closing control method that improves the linkage between the actuator and the latch actuator reduces the structural design cost.

[0018] The use of an external actuator actuation structure reduces system complexity, increases the storage capacity of fire extinguishing medium, and effectively improves the efficiency of fire extinguishing medium delivery without affecting the delivery of fire extinguishing medium.

[0019] A door delivery method combining gravity delivery and active control is adopted to ensure the door opening time requirements of fire extinguishing efficiency, while making full use of gravity impact to improve door opening efficiency.

[0020] A door closing control method that links a lift actuator with a latch actuator is adopted. For external actuators, closing the door solely with the lift actuator requires enormous actuator output force to overcome seal compression, posing challenges in terms of device space requirements, device structure, and actuator design. Linking the lift actuator with the latch actuator significantly reduces lift actuator output requirements, achieving optimal door closing efficiency. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] In order to describe the implementation of the above and other features of the present invention, a more particular description of the invention briefly described above will be presented with reference to exemplary embodiments of the invention shown in the accompanying drawings. It will be understood that these drawings depict only exemplary embodiments of the invention and are not to be considered limiting of its scope, and the invention will be described and explained with additional specificity and detail through the use of the accompanying drawings. In the drawings:

[0022] Figure 1 is a bottom view of an aircraft with a launch door assembly according to an embodiment of the present invention;

[0023] Figure 2 yes Figure 1 A bottom view of the optional first set of door targets and door close proximity sensors of the launch door assembly;

[0024] Figure 3 yes Figure 1 A bottom view of the optional second set of door targets and door-close proximity sensors for the launch door assembly;

[0025] Figure 4 yes Figure 1 A bottom view of a linkage rod of a lift actuator of a launch hatch assembly;

[0026] Figure 5 is a simplified diagram of the mechanism movement of the launch hatch assembly according to an embodiment of the present invention, wherein the launch hatch is in a closed ready position and the latch shaft is in an unlatched position;

[0027] Figure 6 is a simplified diagram of the mechanism movement of the launch hatch assembly according to an embodiment of the present invention, wherein the launch hatch is in a closed ready position and the latch shaft is in an up-latch position;

[0028] Figure 7 is a graph showing the relationship between the speed of the lifting actuator and the angle of the delivery hatch when opening the delivery hatch according to the delivery hatch control method of an embodiment of the present invention;

[0029] Figure 82 is a diagram showing the relationship between the speed of the lifting actuator and the angle of the delivery hatch when closing the delivery hatch according to the delivery hatch control method of an embodiment of the present invention.

[0030] The accompanying drawings are generally drawn to scale, however, the dimensions in the drawings are merely illustrative and not necessarily strictly to scale, but are intended to provide clarity. In other embodiments, other relative dimensions may be used. Here and throughout the following description, identical features appearing in different drawings are denoted by the same or similar reference numerals.

[0031] List of reference numerals:

[0032] 1 Launch hatch assembly

[0033] 110 First launch hatch

[0034] 110a First side

[0035] 110b Second side

[0036] 110c Third side

[0037] 110d Fourth side

[0038] 111 First launch hatch pivot

[0039] 112 Door locking hook

[0040] 120 First lifting actuator

[0041] 121 Connecting rod

[0042] 130 First Latch Shaft

[0043] 131 first latch portion

[0044] 140 First latch actuator

[0045] 150 Hatch Target

[0046] 151 Door closing position proximity switch

[0047] 160 Latch Target

[0048] 161 Latch in place proximity switch

[0049] 162 Unlatch position proximity switch

[0050] 210 Second launch hatch

[0051] 220 Second lifting actuator

[0052] 230 Second Latch Shaft

[0053] 240 Second latch actuator DETAILED DESCRIPTION

[0054] First, the present invention relates primarily to a launch hatch assembly for a firefighting aircraft, particularly, but not limited to, a launch hatch assembly for a branch airliner converted into a firefighting aircraft.

[0055] "Fit" in the context of the present invention is intended to describe that the shape of at least a portion of one component and the shape of at least a portion of another component can fit with each other. The "fit" does not require complete shape matching, and can be partial shape matching. For example, one component is convex and can be received in a curved recess of another component, or the key of one component can be partially received in the groove of another component. As long as there is a force transmission path, no matter how many, it is within the scope of the present invention.

[0056] As used herein, the terms "comprising," "having," "including," and variations thereof are intended as open-ended transitional phrases, terms, or words requiring the presence of specified elements / steps and also allowing for the presence of additional elements / steps.

[0057] In the present invention, unless explicitly stated otherwise, the terms "first", "second", etc. are not intended to indicate any difference in order, position, quantity or importance, but are merely used as labels to distinguish different positions and components, to distinguish one element, component, region and / or position from another element, component, region and / or position.

[0058] The numerical values ​​used herein should be understood to include the same numerical values ​​when reduced to the same number of significant figures, as well as numerical values ​​that differ from the numerical values ​​by less than the experimental error of the numerical values ​​determined by conventional measurement techniques of the type described in this application. The numerical values ​​provided in the various embodiments are only examples and are not intended to limit the scope of the present invention.

[0059] In a non-limiting example, the fire-fighting aircraft of the present invention includes a fire-extinguishing medium opening at the belly below the fuselage, and at least one delivery hatch for sealingly blocking the fire-extinguishing medium opening.

[0060] In a non-limiting example, the launch hatch assembly 1 of the present invention includes at least one launch hatch 110, 210, and the outer contour shape of at least one launch hatch can be a rectangle with rounded corners but is not limited thereto, and can also be other shapes based on actual needs, such as having a notch in the outer contour shape to avoid the frame of the fuselage.

[0061] The at least one delivery hatch may include two or more delivery hatches, and the arrangement of these delivery hatches may be adaptively changed based on the arrangement of the fire extinguishing medium storage containers and the fire extinguishing medium openings inside the fuselage.

[0062] For example, the at least one delivery door may include two delivery doors 110 and 210, and the first delivery door 110 and the second delivery door 210 are arranged in a mirror-symmetrical manner relative to the center line of the fuselage in the span direction of the aircraft, and together block the fire extinguishing medium outlet.

[0063] For example, the at least one delivery hatch may include two or more delivery hatches, and the delivery hatches are arranged in a row in the heading direction of the flight and together block the fire extinguishing medium outlet.

[0064] The delivery hatch 110 has at least a closed position and an open position. In the closed position, it can sealably block the fire extinguishing medium opening, and in the open position, it does not interfere with the delivery of the fire extinguishing medium. Preferably, a sealing member, such as a rubber sealing ring, is arranged in a ring around the outer periphery of the delivery hatch. The sealing member can be compressed to provide close contact between the delivery hatch 110 and the fire extinguishing medium opening.

[0065] The launch hatch 110 may also include a closed standby position, in which the seal of the launch hatch 110 substantially contacts the fire extinguishing medium opening. Because the seal requires compression to provide a seal, the compressive force may be significant. The present invention operates the lift actuator 120 and / or the latch actuator 140 to compress the seal, thereby moving the launch hatch 110 from the closed standby position to the closed position, as described in detail below.

[0066] The delivery hatch 110 may further include a maximum angle position, which is a delivery hatch position at which the delivery hatch 110 has a preset maximum opening angle that does not cause damage to the electric actuator, and will be described in detail below.

[0067] The deployment door 110 may include a door pivot 111 on its first side 110a and be pivotally connected to the fuselage of the firefighting aircraft via the door pivot 111. Preferably, the first side 110a is designed so that the deployment door 110 opens in the spanwise direction. Considering that the present invention can be used in firefighting aircraft converted from fixed-wing aircraft, which fly at speeds far higher than those of helicopters and seaplanes and are subject to greater aerodynamic forces in the heading direction, opening the door in the spanwise direction can avoid the additional resistance to opening and closing the door due to aerodynamic drag.

[0068] The launch door 110 may include a door locking hook 112 on its side, which cooperates with a latch portion 131 of a latch shaft 130 provided on the fuselage to compress the seal of the launch door 110 and lock the launch door 110, which will be described in detail below.

[0069] The door locking hook 112 is preferably arranged on the third side 110c opposite to the first side 110a, or can also be arranged on the second side 110b or the fourth side 110d adjacent to the first side 110a, but close to the third side 110c. Therefore, compared with the position far away from the third side 110c, the force arm of the force for closing the launch door (that is, the distance between the door locking hook 112 and the pivot axis of the door pivot portion 111 of the first side 110a) can be longer, wherein at least a part of the force for closing the launch door is provided by the latch shaft 130 and the latch actuator 140, which will be described in detail below.

[0070] In a non-limiting example, the launch door assembly 1 of the present invention includes a lift actuator 120. The lift actuator 120 is connected to the fuselage and the door 110 from outside the aircraft, respectively, and actuates the door 110 to pivot around the door pivot 111.

[0071] For example, a first end of the lift actuator 120 is connected to the fuselage from outside the aircraft near the first side 110 a and a second end is connected to the middle section of the launch door 110 from outside the aircraft.

[0072] In the present invention, the lifting actuator 120 is arranged outside the aircraft to avoid occupying space inside the fuselage, avoiding blocking or jamming of non-fluid fire extinguishing media, such as colloidal fire extinguishing bombs, when the fire extinguishing media is released, and avoiding additional requirements such as waterproof design of the built-in lifting actuator.

[0073] Considering that the present invention can be used in firefighting aircraft converted from fixed-wing aircraft, which fly at high speeds and high ground clearance, it is necessary to quickly open the release hatch to release the fire extinguishing medium in a short period of time. Preferably, the lifting actuator 120 is an electric actuator that does not include a hydraulic system and includes, for example, a motor, gears, and a connecting rod 121 to achieve high-precision and high-speed control of the lifting actuator 120.

[0074] In a non-limiting example, the launch hatch assembly 1 of the present invention includes a latch shaft 130. The latch shaft 130 is rotatably disposed on the fuselage, and preferably at the third side 110c of the launch hatch 110 to obtain a larger moment arm of the compression force as described above.

[0075] The latch shaft 130 includes a latch portion 131 that cooperates with the launch hatch locking hook portion 112, and the latch portion 131 and the launch hatch locking hook portion 112 are engaged and disengaged by the rotation of the latch shaft 130. Therefore, the latch shaft 130 is designed to be coaxial with the hatch locking hook portion 112.

[0076] In a non-limiting example, the launch hatch assembly 1 of the present invention includes a latch actuator 140 for actuating the rotation of the latch shaft 130. Preferably, it is an electric actuator and includes, for example, a motor, gears, and a connecting rod 121 to control the latch shaft 130 with high precision and high speed.

[0077] The present invention will be further described below with reference to specific embodiments and accompanying drawings. More details are set forth in the following description to facilitate a full understanding of the present invention. However, the present invention can obviously be implemented in a variety of other ways different from the description herein. Those skilled in the art can make similar generalizations and deductions based on actual application situations without violating the connotation of the present invention. Therefore, the scope of protection of the present invention should not be limited by the content of this specific embodiment.

[0078] A coordinate system is provided in the figures for reference, the z-axis may be the vertical axis (e.g., parallel to the direction of gravity), the x-axis may be the longitudinal axis (e.g., parallel to the heading direction of the aircraft), and the y-axis may be the horizontal axis (e.g., parallel to the span direction of the aircraft).

[0079] When referring to directions, a positive direction may refer to the direction of the arrows for the y-, x-, and z-axes, while a negative direction may refer to the opposite direction of the arrows for the y-, x-, and z-axes. A filled circle may indicate an arrow and axis facing toward or toward the view. An unfilled circle may indicate an arrow and axis facing away from or toward the view.

[0080] Figure 1 A bottom view of an aircraft with a launch door assembly according to an embodiment of the present invention is schematically shown.

[0081] In this example, the at least one delivery door may include two delivery doors 110 and 210, and the first delivery door 110 and the second delivery door 210 are arranged in mirror symmetry with respect to the center line of the fuselage in the span direction of the aircraft and together block the fire extinguishing medium outlet.

[0082] Preferably, the second lift actuator 220, the second latch shaft 230, and the second latch actuator 240 corresponding to the second launch door 210 may be arranged in a mirror-symmetrical manner with the first lift actuator 120, the first latch shaft 130, and the first latch actuator 140. It will be appreciated that the specific placement of the second lift actuator 220, the second latch shaft 230, and the second latch actuator 240 is not limited to a mirror-symmetrical arrangement. For example, in this embodiment, based on the actual space limitations of the aircraft fuselage, the first latch actuator 140 and the second latch actuator 240 may also be located on the same side of the aircraft fuselage in the span direction.

[0083] Figure 2 yes Figure 1A bottom view of the optional first set of door targets 150 and the door closed proximity sensor 151 of the launch door assembly, Figure 3 yes Figure 1 Bottom view of the launch door assembly's optional second set of door targets and door-close proximity sensors.

[0084] The delivery door assembly 1 according to an embodiment of the present invention further includes a door target 150, which is arranged on the fourth side 110d of the first delivery door 110 adjacent to the first side 110a; and a door-closed-position proximity switch 151, which is arranged on the fuselage and is arranged close to the fourth side 110d, and is arranged so that when the first delivery door 110 is in the closed preparation position, the door-closed-position proximity switch 151 can sense the door target 150.

[0085] Figure 4 A bottom view of the connecting rod 121 of the first lifting actuator 120 is schematically shown.

[0086] The first end of the first lifting actuator 120 is mounted on the lower wall of the aircraft. Thus, during the closing of the first delivery door 110, the actuating torque of the first lifting actuator 120 gradually decreases. Therefore, a very large output of the first lifting actuator 120 is required to completely close the first delivery door 110.

[0087] Therefore, a connecting rod 121 can be used to connect the second end of the first lifting actuator 120 to the first delivery hatch 110. The connecting rod 121 changes the direction of force transmission, thereby increasing the torque acting on the first delivery hatch 110, and thus the required output of the first lifting actuator 120 can be reduced.

[0088] The form of the connecting rod 121 is not limited thereto, and may be any form suitable for increasing the torque acting on the first launch hatch 110 .

[0089] Figure 5 The present invention schematically illustrates a simplified diagram of the mechanism movement of the launch hatch assembly 1 according to an embodiment of the present invention, wherein the first launch hatch 110 is shown in a closed preparation position by a solid line and in a desired closed position by a dotted line, and at this time, the first latch shaft 130 and the first latch portion 131 thereon are rotated to the unlatched position.

[0090] The launch hatch assembly 1 according to an embodiment of the present invention further includes a latch shaft target 160, which is disposed on the outer circumferential surface of the first latch shaft 130. In this example, the first latch portion 131 is crescent-shaped, and the latch shaft target 160 is disposed at one end, specifically, on a radially extending tab of the first latch shaft 130.

[0091] The delivery hatch assembly 1 according to the embodiment of the present invention further includes an unlatched position proximity switch 162 (for example, a proximity sensor). The unlatched position proximity switch 162 is provided on the fuselage and is provided close to the outer peripheral surface of the first latch shaft 130. The unlatched position proximity switch 162 is provided so that when the first latch shaft 130 is in the unlatched position, for example, Figure 5 As shown, the unlatch position proximity switch 162 is capable of sensing the latch shaft target 160 .

[0092] Figure 6 The schematic diagram shows the mechanism movement of the launch hatch assembly 1 according to an embodiment of the present invention, wherein the first launch hatch 110 is shown in a closed position by a solid line, and at this time the first latch shaft 130 and the first latch portion 131 thereon are rotated to the upper latch position.

[0093] The launch hatch assembly 1 according to the embodiment of the present invention further includes a latch position proximity switch 161 (for example, a proximity sensor). The latch position proximity switch 161 is provided on the fuselage and is provided close to the outer peripheral surface of the first latch shaft 130. The latch position proximity switch 161 is provided so that when the first latch shaft 130 is in the latch position, for example, Figure 6 As shown, the latch position proximity switch 161 can sense the latch shaft target 160.

[0094] Here, the latch position proximity switch 161 and the unlatched position proximity switch 162 are set to correspond to different angular positions of the outer peripheral surface of the first latch shaft 130, such as the angular position of the latch shaft target 160 when the first latch shaft 130 is in the predetermined latch position and unlatched position.

[0095] Figure 7 A diagram schematically illustrates the relationship between the speed of lift actuator 120 and the angle of launch door 110 when opening launch door 110, according to a method for controlling the launch door according to an embodiment of the present invention. It should be understood that the specific value of the angle is not limited to this, but is determined based on actual aircraft conditions, such as aircraft model, airspeed, altitude, payload, and environmental conditions. In this example, the door angle of launch door 110 in the closed position is approximately 20°.

[0096] When preparing for delivery, the aircraft control needs to be powered on first, then the delivery pre-position switch is pressed, and the delivery button is pressed at an appropriate time. At this time, the delivery door assembly 1 according to the present invention will go through the following steps.

[0097] First, the latch actuator 140 actuates the latch shaft 130 to rotate, the latch shaft 130 rotates to the unlatched position to allow the launch door 110 to open, and the first latch actuator 140 stops.

[0098] Subsequently, the delivery hatch 110 adopts gravity delivery, specifically, the door is opened and the fire extinguishing medium is released under the action of the gravity of the fire extinguishing medium. When actually implemented, for example, on a fixed-wing firefighting aircraft, the delivery hatch 110 is opened and delivered in less than 1 second. Figure 7 The figure also shows an exemplary curve of the relationship between the speed of the follow-up lifting actuator 120 and the angle of the launch hatch 110 when the door is opened only under the action of gravity. It can be understood that the specific value of the angle is not limited to this.

[0099] When the release rate of the fire extinguishing medium under the action of gravity alone meets the preset release requirements, the lifting actuator 120 follows, for example, during the period from t40 to t41, so that the opening speed v of the lifting actuator 120 (for example, the opening speed v1 at t41) is greater than or equal to the expected speed.

[0100] In which, when the delivery rate of the fire extinguishing medium under the action of gravity alone does not meet the preset delivery requirements, the lifting actuator 120 actively actuates the delivery hatch 110 to move toward the open position, for example, during the period from t41 to t42 to t43, so that the opening speed v of the lifting actuator 120 (for example, the opening speed v2 at t42, the opening speed v3 at t43) meets the expected speed until the opening position of the delivery hatch 110 as described below is reached, so as to meet the goal of opening the delivery hatch 110 to the open position within 0.8s, 0.6s, for example.

[0101] Then, when the launch hatch 110 reaches the open position, for example at t43, the lift actuator 120 is actuated and resists the movement of the hatch 110. Figure 7 In the example shown, the launch door angle is 98° when the door 110 is in the open position, which is referred to as the clear opening.

[0102] When the launch hatch 110 opens to the preset maximum opening angle, for example, at t44, the lifting actuator 120 is locked and maintains the current position of the launch hatch 110. Figure 7 In the example shown, the maximum opening angle of the launch hatch 110 is 110°.

[0103] After exceeding the open position, i.e., the net opening, the actuator 120 is lifted for buffering. Under the action of gravity, spring force, negative pressure, etc., the speed of the launch hatch 110 drops to zero, and part of the energy is converted into elastic energy and gravitational potential energy, and part is consumed by friction; finally, the launch hatch 110 is fixed to the maximum opening angle.

[0104] Figure 8The diagram schematically shows the relationship between the speed of the lifting actuator 120 and the angle of the delivery door 110 when closing the delivery door 110 according to the delivery door control method of an embodiment of the present invention. It can be understood that the specific value of the angle is not limited to this, but is specifically set based on the actual aircraft situation.

[0105] After a preset, fixed delay, the lift actuator 120 unlocks and begins to retract, actuating the launch hatch 110 to open from its maximum opening angle to a closed, ready-to-open position. For example, the launch hatch 110 opens from 110° to 17.2°. As described above, the hatch angle in the closed position is, for example, approximately 20°. However, a seal is disposed around the launch hatch 110. During the rotation of the latch shaft 130 to the unlatched position, the compressed seal returns to its original volume, resulting in a hatch angle of, for example, approximately 17.2° in the closed, ready-to-close position.

[0106] The lift actuator 120 then locks and maintains the current position of the launch door 110 .

[0107] Then, the latch actuator 140 actuates the latch shaft 130 to rotate, and the latch shaft 130 rotates to the latch position. Figure 5 、 Figure 6 The latch shaft 130 rotates from the unlatched position toward the latched position. After a certain idle stroke, the latch portion 131 contacts the door locking hook 112 of the launch hatch 110. The latch actuator 140 actuates the latch shaft 130 to rotate to the latched position, so that the launch hatch 110 enters the closed position.

[0108] In the embodiment shown in the accompanying drawings, the lifting arm of the lifting actuator 120 for lifting the delivery hatch 110 is relatively long, so the lifting actuator 120 locks and maintains the current position of the delivery hatch 110, that is, the closed preparatory position, and the latch shaft 130 is rotated to further compress the seals arranged around the delivery hatch 110 as described above, so that when the delivery hatch 110 moves to the closed position, the seals can seal the fire extinguishing medium opening of the fuselage.

[0109] When the first latch shaft 130 reaches the latch position, the first latch actuator 140 stops actuating, thereby releasing the locking of the lifting actuator 120 and releasing the structural deformation stress.

[0110] By releasing the compression and stiffness characteristics of the lifting actuator 120, the connecting rod 121, the launch door 110 and the fuselage structure, the travel requirement of the lifting actuator 120 caused by the latch shaft 130 actuating the launch door 110 is compensated. Specifically, the travel from the aforementioned door closing preparation position to the final closed position is about 1.5 to 2 mm in this example. Figure 8 The thick solid line in FIG. 1 represents that the compression amount of the lifting actuator 120 is released, and for example, the opening angle of the launch hatch 110 is from 17.2° to 20°.

[0111] In order to make the objectives, technical solutions and advantages of the embodiments of the present invention more clear, the technical solutions of the present invention are clearly and completely described above in conjunction with the specific embodiments of the present invention and the accompanying drawings.

[0112] It should be understood that the steps shown above in conjunction with the specific embodiments are illustrative, and those skilled in the art may add or delete corresponding steps, and may adjust the execution order of one or some steps, or replace one or more steps with similar steps.

[0113] Although various embodiments have been described above, it should be understood that the embodiments described are only some of the embodiments of the present invention, rather than all of the embodiments, and are presented in an exemplary rather than restrictive manner. It will be apparent to those skilled in the relevant art that the disclosed subject matter can be implemented in other specific forms without departing from its spirit and essential characteristics.

[0114] In this process, various elements that are important to the present invention or that are conducive to further development of the present invention will be mentioned in the context of specific examples, but some of these elements can also be used to further develop the present invention when separated from the content and other features of the corresponding examples. Therefore, the embodiments described above are to be considered in all respects as illustrative and non-restrictive, and are not to be used as a basis for limiting the present invention in any way.

[0115] Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without inventive effort are within the scope of protection of the present invention. The present disclosure also includes various modifications and variations within the scope of equivalence. In addition, various combinations and methods, as well as other combinations and methods including only one element, more than one element, or less than one element, are also within the scope and scope of the present disclosure.

Claims

1. A delivery door assembly for a fire-fighting aircraft, characterized in that: The delivery hatch assembly (1) comprises: a first delivery hatch (110), the first delivery hatch (110) including a first delivery hatch pivot portion (111) at a first side edge (110a) and being pivotally connected to the fuselage of the fire-fighting aircraft via the first delivery hatch pivot portion (111), the first delivery hatch (110) blocking the fire-extinguishing medium outlet of the fuselage, and the first delivery hatch (110) including a first hatch locking hook portion (112); a first lifting actuator (120) connected to the fuselage and the first delivery door (110) from outside the aircraft, respectively, and actuating the first delivery door (110) to pivot around the first delivery door pivot portion (111); a first latch shaft (130), the first latch shaft (130) being rotatably provided on the fuselage and having a rotation center coaxial with the first door locking hook portion (112), the first latch shaft (130) comprising a first latch portion (131) cooperating with the first door locking hook portion (112), the first latch portion (131) and the first door locking hook portion (112) being engaged with and disengaged from each other by rotation of the first latch shaft (130); and A first latch actuator (140) actuates the first latch shaft (130) to rotate.

2. The launch hatch assembly according to claim 1, characterized in that: The first end of the first lift actuator (120) is connected to the fuselage from outside the aircraft near the first side (110a), and A second end of the first lift actuator (120) is connected to a middle section of the first launch door (110) from outside the aircraft.

3. The launch hatch assembly according to claim 1, characterized in that: The delivery hatch assembly (1) further comprises: a second delivery hatch (210), wherein the first delivery hatch (110) and the second delivery hatch (210) are arranged in a mirror-symmetrical manner relative to the center line of the fuselage in the span direction of the aircraft and together block the fire extinguishing medium outlet, and the second delivery hatch (210) includes a second hatch locking hook; a second lifting actuator (220) connected to the fuselage and the second delivery door (210) at both ends, respectively, and actuating the second delivery door (210) to pivot between an open position and a closed position; a second latch shaft (230), the second latch shaft (230) being rotatably provided on the fuselage and having a rotation center coaxial with the second door locking hook portion, the second latch shaft (230) comprising a second latch portion cooperating with the second door locking hook portion, the second latch portion and the second door locking hook portion being engaged and disengaged by the rotation of the second latch shaft (230); and A second latch actuator (240) actuates the second latch shaft (230) to rotate.

4. The launch hatch assembly according to claim 3, characterized in that: The first latch actuator (140) and the second latch actuator (240) are arranged on the same side of the fuselage in the span direction of the aircraft.

5. The launch hatch assembly according to claim 1, characterized in that: The delivery hatch assembly (1) further comprises: a hatch target (150), the hatch target (150) being disposed on a fourth side (110d) of the first delivery hatch (110) adjacent to the first side (110a); and A door-closed position proximity switch (151) is provided on the fuselage, close to the fourth side (110d), and configured so that when the first delivery hatch (110) is in the closed standby position, the door-closed position proximity switch (151) can sense the hatch target (150).

6. The launch hatch assembly according to claim 1, characterized in that: The delivery hatch assembly (1) further comprises: a latch shaft target (160), the latch shaft target (160) being provided at a predetermined position on the outer peripheral surface of the first latch shaft (130); a latching position proximity switch (161), the latching position proximity switch (161) being disposed on the fuselage and being disposed close to the outer peripheral surface of the first latch shaft (130), and being disposed so that when the first latch shaft (130) is in the latching position, the latching position proximity switch (161) can sense the latch shaft target (160); and An unlatching position proximity switch (162) is provided on the fuselage, is provided close to the outer peripheral surface of the first latch shaft (130), and is provided so that when the first latch shaft (130) is in the unlatching position, the unlatching position proximity switch (162) can sense the latch shaft target (160).

7. The launch hatch assembly according to claim 1, characterized in that: The first lift actuator (120) and the first latch actuator (140) are electrically actuated mechanisms that do not include a hydraulic system.

8. A method for controlling a launch hatch for a firefighting aircraft, characterized in that: The delivery hatch control method comprises the following steps when opening the delivery hatch: The first latch actuator (140) actuates the first latch shaft (130) to an unlatched position; The first delivery hatch (110) opens under the action of the gravity of the fire extinguishing medium and delivers the fire extinguishing medium; When the delivery rate of the fire extinguishing medium under the action of gravity alone meets the preset delivery requirement, the first lifting actuator (120) moves with it, and When the delivery rate of the fire extinguishing medium under the action of gravity alone does not meet a preset delivery requirement, the first lifting actuator (120) actuates the first delivery hatch (110) to move toward an open position; When the first delivery hatch (110) reaches the open position, the first lifting actuator (120) is actuated and resists the movement tendency of the first delivery hatch (110); and When the first delivery hatch (110) is opened to a preset maximum opening angle, the first lifting actuator (120) is locked and maintains the current position of the first delivery hatch (110).

9. A method for controlling a launch hatch for a firefighting aircraft, characterized in that: The delivery hatch control method comprises the following steps when closing the delivery hatch: The first lifting actuator (120) unlocks and actuates the first launch hatch (110) to a closed ready position; The first lifting actuator (120) locks and maintains the current position of the first launch hatch (110); The first latch actuator (140) actuates the first latch shaft (130) to the latched position, and when the first latch shaft (130) reaches the latched position, the first latch actuator (140) stops actuating; The first lifting actuator (120) is unlocked and the structural deformation stress is released.

10. The method for controlling the delivery hatch according to claim 9, characterized in that: In the step of the first latch actuator (140) actuating the first latch shaft (130) to the latched position, the launch hatch control method further comprises: The first latch shaft (130) rotates from the unlatched position toward the latched position, The first latch portion (131) of the first latch shaft (130) contacts the first hatch locking hook portion (112) of the first launch hatch (110), The first latch shaft (130) continues to rotate so that the first launch hatch (110) pivots from the closed preparation position toward the closed position. The first latch actuator (140) actuates the first latch shaft (130) to rotate to an upper latch position.

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