Low-altitude parachute opening device based on solid propellant and parachute opening method

Abstract

The invention relates to a low-altitude parachute opening device based on a solid propellant and a parachute opening method. Comprising a parachute shooting rocket and a parachute pack connecting mechanism. The parachute shooting rocket comprises an ignition head, a propellant powder shell, propellant powder, an elastic gasket, a grain, a shell, a tablet pressing piece, a nozzle and a sealing piece. The front end of the shell is connected with an ignition head, a propellant shell is arranged in the front end of the shell, propellant powder is pressed in the propellant shell through an elastic gasket, the grain is arranged in a shell body, the elastic gasket is provided with a through hole communicated with the propellant powder and the grain, the tail end of the grain is pressed through a tablet, the tail end of the shell is provided with a nozzle, and a sealing piece is arranged on the throat portion of the nozzle. Through short-time efficient thrust output, the problems that a traditional parachute is complex in low-altitude airflow, insufficient in parachute opening time and the like are solved.

Description

TECHNICAL FIELD

[0001] The application belongs to the field of aerospace low-altitude recovery and emergency parachute opening, and particularly relates to a low-altitude parachute opening device based on solid propellant and a parachute opening method. BACKGROUND

[0002] As a kind of efficient and reliable aerodynamic deceleration means, the parachute deceleration system has been widely applied in many key fields such as safe recovery of unmanned aerial vehicles, emergency landing of aircrafts, air supply and landing of spacecraft return capsules. The system can sharply increase the air resistance of the object in the process of descending by unfolding a large area of parachute cloth at a specific stage, thereby reducing the speed of the object in the process of descending. This deceleration method can significantly reduce the impact load when landing or landing, thereby protecting the unmanned aerial vehicle structure, precision instruments and air supply materials from damage.

[0003] The traditional parachute opening methods mainly include pulling the pull ring to open the parachute, opening the parachute by fixing the pull rope, triggering the parachute by the barometer, and opening the parachute by the timer. The opening process of the parachute needs to follow the principle of aerodynamics, and the parachute cloth is stretched by the resistance and inflated. The dynamic unfolding process needs a certain buffer time window. If the height is insufficient when the parachute is opened, the parachute cannot be fully unfolded in a limited time, which will lead to a significant decrease in deceleration efficiency or even failure, thereby losing the protection effect.

[0004] With the development of low-altitude economy, unmanned aerial vehicles and emerging flying car industries have experienced explosive growth, and their activity airspace is mainly concentrated in the low-altitude area below 500 meters. Once such aircrafts have engine failure, loss of control or other sudden emergencies in low-altitude, the reaction time for emergency rescue is extremely limited. The traditional parachute system relies on gravity to fall to reach the opening speed, and it often cannot be fully unfolded or effectively decelerated in the ultra-low altitude below 500 meters, thereby losing its protection effect. SUMMARY

[0005] The purpose of the present application is to provide a low-altitude parachute opening device based on solid propellant and a parachute opening method, which breaks through the "height-time" bottleneck of low-altitude emergency parachute opening and effectively ensures the safety of low-altitude flight. The device actively and rapidly ejects the parachute to a safe opening position and forcibly inflates and unfolds through the built-in propulsion system at the moment of emergency triggering, greatly shortens the height and time required for the opening process, realizes the instantaneous release and rapid inflation and unfolding of the parachute cloth through the rope traction system, and ensures the stable unfolding posture of the parachute under extreme conditions.

[0006] The technical solution for achieving the purpose of the present application is a low-altitude parachute opening device based on solid propellant, which comprises a parachute launching rocket and a parachute bag connecting mechanism.

[0007] The umbrella rocket comprises an ignition head, a launching charge shell, launching charge, an elastic gasket, a charge column, an outer shell, a pressure charge sheet, a nozzle and a sealing sheet; the outer shell front end is connected with the ignition head, the inner part of the outer shell front end is provided with the launching charge shell, the launching charge is pressed into the launching charge shell through the elastic gasket, the charge column is arranged in the outer shell main body, the elastic gasket is provided with a through hole communicating the launching charge and the charge column, the tail end of the charge column is pressed through the pressure charge sheet, the outer shell tail end is provided with the nozzle, and the nozzle throat is provided with the sealing sheet.

[0008] Further, the outer shell front end is semispherical, the middle part of the front end is provided with an outer shell threaded hole for connecting the ignition head, the outer shell main body is cylindrical, the cylindrical tail end is connected with the nozzle, the outer shell cylindrical rear end is externally and uniformly provided with a boss, each boss is provided with a through hole, and the fireproof rope I of the umbrella package connecting mechanism passes through the through hole and is bound to the umbrella rocket.

[0009] Further, the ignition head is an electric ignition head, comprising an ignition head signal input end and an ignition head connecting section;

[0010] The ignition head connecting section is connected with the outer shell threaded hole through screw threads, and the ignition head signal input end is located outside the outer shell after connection for receiving the electric signal from the carrier; the ignition head connecting section is in contact with the launching charge for generating sparks to ignite the launching charge.

[0011] Further, the launching charge shell main body is arc-shaped, closely adheres to the inner wall of the outer shell front end, is hollow inside, is used for placing the launching charge, has a cylindrical section opening at one end, cooperates with the elastic gasket to compress the launching charge, and has a launching charge shell threaded hole at the center of the other end for connecting the ignition head.

[0012] Further, the elastic gasket is integrally composed of an elastic gasket large-radius cylindrical section and an elastic gasket small-radius cylindrical section, the elastic gasket large-radius cylindrical section cooperates with the cylindrical section opening at one end of the launching charge shell, the elastic gasket small-radius cylindrical section one end cooperates with one end of the solid charge column, and is used for providing elastic support for the solid charge column; the elastic gasket is internally provided with a plurality of through holes for ensuring the flame generated by the launching charge to pass through.

[0013] Further, the charge column is a solid fuel with a cylindrical shape and a star-shaped through hole with twelve angles inside; the charge column is arranged in the outer shell, and the outer surface closely adheres to the inner surface of the outer shell.

[0014] Further, the pressure charge sheet is a cylindrical structure, the outer surface is provided with screw threads for cooperating with the inner screw threads at one end of the outer shell cylindrical section, the pressure charge sheet is internally provided with a through hole for the flame of the charge column to pass through.

[0015] Further, the nozzle is overall convergent-divergent streamline type, the nozzle connecting section of the nozzle is provided with screw threads for cooperating with the outer shell connecting section screw threads, the sealing sheet material of the nozzle throat is rubber, and is used for preventing the charge column from being damp after contacting with the air.

[0016] Further, the umbrella bag connecting mechanism further comprises a fireproof ring and a fireproof rope II;

[0017] The inner diameter of the fireproof ring is larger than the outer diameter of the shell, the fireproof ring is composed of thick and thin arc segments arranged alternately, the fireproof rope I has four, the boss on the shell has four, one end of each fireproof rope I passes through the through hole and is bound to the umbrella rocket, and the other end is connected to the four large-radius annular rings, i.e., thick annular rings, of the fireproof ring, the fireproof rope II is composed of four sub-ropes and a main rope, one end of the main rope is connected to the four sub-ropes, and the other end is connected to the parachute bag, and the four sub-ropes are bound to the four small-radius arcs of the fireproof ring.

[0018] A method for opening the umbrella by using the low-altitude umbrella opening device, the ignition head is activated after receiving the electric signal, and generates a high-temperature spark in a microsecond level, ignites the preloaded launching powder in the shell, when the launching powder is ignited, the high-temperature flame released forms a directional flame beam through the through hole in the center of the elastic gasket, and ignites the propellant grain in sequence; the high-temperature and high-pressure gas generated by the burning of the propellant grain is guided through the internal star-shaped through hole and is sprayed out at high speed from the bottom nozzle, forming a reaction force thrust, which instantaneously launches the whole propulsion system; when the parachute is completely pulled out, the umbrella rocket still outputs a pulling force to the fireproof rope, and once the pulling force exceeds the limit pulling force of the pre-set weakened arc segment on the fireproof ring, the fireproof ring breaks, and the umbrella rocket is separated from the parachute bag.

[0019] Compared with the prior art, the present application has the following advantages:

[0020] 1. Twelve-corner star-shaped through hole propellant grain design:

[0021] The propellant grain structure with a twelve-corner star-shaped through hole is adopted, the burning surface area is greatly increased through geometric optimization, and the burning rate efficiency is effectively improved; the polygonal structure of the star-shaped hole forms uniform multidirectional diffusion channels in the burning process, ensures that the fuel is rapidly and stably decomposed, thereby shortening the burning time and improving the consistency of energy release.

[0022] 2. Streamlined shell and boss tail wing integrated design:

[0023] The upper part of the shell adopts a semicircular streamlined structure, which can reduce the aerodynamic resistance in the flight process; the boss structure arranged at a position slightly below the middle part has multiple functions: on the one hand, it serves as a node for connecting the parachute rope, ensuring the stability of load transmission; on the other hand, it forms a natural tail effect by lowering the system center of mass, enhancing the stability against wind disturbance; this structural innovation realizes the high integration of aerodynamic performance and mechanical connection function, ensuring the attitude controllability of the system in complex airflows.

[0024] 3. Self-adaptive elastic boss gasket:

[0025] The elastic gasket adopts a boss structure design, which not only firmly fixes the propellant column through mechanical fitting, but also leaves a circumferential combustion space to avoid affecting the burning rate due to limited space during combustion; the elastic material characteristics can dynamically adapt to the deformation of the propellant column during daily storage, effectively absorb thermal stress through the reserved buffer space and elastic compression effect, and prevent structural failure or abnormal combustion caused by thermal deformation.

[0026] 4. Modular detachable nozzle system:

[0027] The nozzle adopts a quick detach design, and is connected with the shell in a modular manner through threaded connection; the design supports quick replacement of the adaptive nozzle according to different application scenarios, and is convenient for regular maintenance and performance calibration; the problems of difficult maintenance of the traditional integrated nozzle and the need for overall replacement after ablation are solved, and the equipment reuse rate is improved. BRIEF DESCRIPTION OF DRAWINGS

[0028] Figure 1 is a half sectional view of the low-altitude parachute opening device of the present application.

[0029] Figure 2 is a schematic view of the ignition head.

[0030] Figure 3 is a half sectional view of the propellant shell.

[0031] Figure 4 is a schematic view of the elastic gasket; (a) is a sectional view, and (b) is a three-dimensional view.

[0032] Figure 5 is a schematic view of the propellant column.

[0033] Figure 6 is a schematic view of the propellant pressing sheet.

[0034] Figure 7 is a half sectional view of the nozzle.

[0035] Figure 8 is a schematic view of the propelling system shell; (a) is a sectional view, and (b) is a three-dimensional view.

[0036] Figure 9 is a working schematic view of the parachute rocket.

[0037] BRIEF DESCRIPTION OF DRAWINGS:

[0038] 1 - igniter, 2 - propellant shell, 3 - propellant, 4 - elastic washer, 5 - propellant column, 6 - outer shell, 7 - pressure plate, 8 - nozzle, 9 - sealing plate, 10 - igniter signal input, 11 - igniter connecting section, 12 - propellant shell threaded hole, 13 - propellant shell cylindrical section opening, 14 - elastic washer large radius cylindrical section, 15 - elastic washer small radius cylindrical section, 16 - star-shaped through hole, 17 - nozzle connecting section, 18 - outer shell threaded hole, 19 - boss, 20 - through hole, 21 - parachute rocket, 22 - rocket tail flame, 23 - fireproof rope I, 24 - fireproof ring, 25 - fireproof rope II, 26 - parachute canopy. DETAILED DESCRIPTION

[0039] The application will be further described in detail below with reference to the accompanying drawings.

[0040] As shown in the drawings, a propelling device for low-altitude parachute opening comprises an igniter 1, a propellant shell 2, a propellant 3, an elastic washer 4, a propellant column 5, a pressure plate 7, a nozzle 8, and an outer shell 6. Figures 1-9 The igniter 1 is an electric igniter comprising an igniter signal input 10 and an igniter connecting section 11. The igniter connecting section 11 is fixed at the center opening of one end of the outer shell 6 by screw connection, and the igniter signal input 10 is outside the outer shell for receiving the electric signal from the carrier. The igniter connecting section 11 is inside the shell and in contact with the propellant 3 to generate sparks to ignite the propellant 3. When the carrier needs to open the parachute, an electric signal is generated, and the igniter 1 generates sparks to ignite the propellant 3 in the outer shell 6 within microseconds after the electric signal. The propellant 3 is inside the outer shell 6, tightly adhering to the inner wall of one end of the shell, with one end in contact with the igniter 1 and the other end in contact with the elastic washer 4. When the propellant 3 is ignited, the flame generated thereby passes through the through hole in the elastic washer to ignite the propellant column 5. The high-temperature and high-pressure gas generated by the combustion of the propellant column 5 is ejected from the nozzle 8 to generate thrust to launch the propelling system.

[0041] The propellant shell 2 is arc-shaped, tightly adhering to the inner wall of one end of the shell, and hollow inside to accommodate the propellant 3. One end of the propellant shell 2 is provided with a cylindrical section opening 13 to cooperate with the elastic washer 4 to compress the propellant 3, and the other end is provided with a threaded hole 12 to connect the igniter.

[0042] The elastic washer 4 is composed of an elastic washer large radius cylindrical section 14 and an elastic washer small radius cylindrical section 15. The elastic washer large radius cylindrical section 14 cooperates with the cylindrical section opening of one end of the propellant shell to compress the propellant. The elastic washer small radius cylindrical section 15 cooperates with the middle of the solid propellant column 5 to provide elastic support for the solid propellant column 5. The elastic washer 4 is provided with a few through holes inside to ensure that the flame generated by the combustion of the propellant 3 can pass through.

[0043]

[0044] ​The propellant grain 5 is essentially a solid fuel, cylindrical in shape, with a dodecagonal star-shaped through-hole 16 inside. The propellant grain 5 is placed inside the outer casing, its outer surface tightly against the inner surface of the outer casing 6. The star-shaped through-hole 16 provides a larger flame contact area compared to a simple cylindrical through-hole, resulting in a faster combustion rate. One end of the propellant grain 5 contacts the elastic gasket 4, and the other end contacts the compressed propellant tablet 7.

[0045] The compression tablet 7 has a cylindrical structure with threads on its outer surface for engaging with the internal threads at one end of the cylindrical section of the outer casing 6. It also has a through hole inside for the flame from the burning propellant 5 to pass through. The main function of the compression tablet 7 is to secure the propellant 5.

[0046] The nozzle 8 has a convergent-divergent streamlined shape, enabling efficient conversion of gas velocity from low to high speed, thereby generating sufficient thrust to rapidly eject the propulsion system from the launch chamber. This nozzle 8 is a detachable nozzle; its nozzle connection section 17 is threaded and can mate with the threaded connection section of the outer casing 6, thus connecting it to the outer casing 6. The throat of the nozzle 8 is equipped with a sealing plate 9, a rubber sheet primarily serving a sealing function to prevent the propellant grain inside from becoming damp upon contact with outside air.

[0047] One end of the outer shell 6 is hemispherical, which can reduce wind resistance to a certain extent. A threaded hole 18 is located in the middle for connecting the ignition head 1. The other end is cylindrical, hollow inside, with an opening at the bottom. The nozzle 8 connects to the outer shell 6 from the bottom. The cylindrical section of the outer shell has four evenly symmetrical protrusions 19, each with a through hole 20 in the middle. The parachute lines can be threaded through these holes and secured to the propulsion system. Besides securing the parachute lines, these protrusions also lower the overall center of gravity of the propulsion system and, to some extent, act as a tail fin, making the propulsion system more stable in flight.

[0048] The specific implementation process is: when the unmanned aerial vehicle or other carrier needs to open the parachute, an electric signal is generated and transmitted to the ignition head, the ignition head generates a spark after receiving the signal to ignite the propellant, the burning propellant ignites the solid propellant column, the high-pressure gas generated by the violent combustion of the propellant column is accelerated through the nozzle and then ejected, generating a strong thrust to push the parachute opening device and the fireproof rope 123 to be ejected instantaneously. The fireproof rope 123 is composed of four ropes, one end of which is connected to the shell through the through hole 20 in the four bosses 19, and the other end is connected to the four large-radius annular rings of the fireproof ring 24. Due to the support of the fireproof ring 24 and the fact that its radius is slightly larger than the radius of the shell 6, the four fireproof ropes are distributed in a conical shape between the fireproof ring 24 and the shell, so that the fireproof rope I is far away from the tail flame. One end of the fireproof rope II 25 is divided into four ropes and is tied to the four small-radius arcs of the fireproof ring, and the four ropes are gathered into a main rope after a certain length. The length can keep the gathering point of the four ropes at a safe distance from the maximum distance point of the tail flame from the nozzle, so as to avoid the fireproof rope II 25 from being eroded by the tail flame. The other end of the fireproof rope II 25 is connected to the parachute bag through the main rope. Through a series of connections, the parachute opening device can drive the parachute bag to move quickly. At the same time, the small-radius arc segment of the fireproof ring 24 is subjected to structural weakening treatment, and when the parachute opening device pulls the parachute bag to the preset opening height, the weakened area will break accurately, realizing the complete separation of the parachute rocket and the parachute bag, and ensuring the smooth completion of the parachute opening process.

[0049] The present application is a small rocket device designed to assist the rapid and reliable deployment of a parachute, mainly used in low-altitude air landing, emergency rescue, heavy air drop and other scenes. Through short-time and high-efficiency thrust output, the traditional parachute problems in complex low-altitude airflow and insufficient opening time are solved.

Claims

1. A low altitude deployment device based on solid propellant, characterized in that, The umbrella rocket (21) and the umbrella package connecting mechanism are connected; The umbrella rocket (21) comprises an ignition head (1), a launching charge shell (2), launching charge (3), an elastic gasket (4), a charge column (5), an outer shell (6), a pressing charge piece (7), a nozzle (8) and a sealing piece (9); the outer shell (6) is connected with the ignition head (1) at the front end, the inner part of the front end of the outer shell (6) is provided with the launching charge shell (2), the launching charge (3) is pressed into the launching charge shell (2) through the elastic gasket (4), the charge column (5) is arranged in the main body of the outer shell (6), the elastic gasket (4) is provided with a through hole for connecting the launching charge and the charge column (5), the tail end of the charge column (5) is pressed by the pressing charge piece (7), the tail end of the outer shell (6) is provided with the nozzle (8), and the throat of the nozzle (8) is provided with the sealing piece (9).

2. The low altitude parachute deployment apparatus of claim 1, wherein The front end of the outer shell (6) is semispherical, the middle of the front end is provided with an outer shell threaded hole (18) for connecting the ignition head (1), the main body of the outer shell (6) is cylindrical, the tail end of the cylindrical body is connected with the nozzle (8), the outer part of the rear end of the cylindrical body is uniformly provided with a boss (19) in the circumferential direction, each boss (19) is provided with a through hole (20) in the middle, the fireproof rope I (23) of the umbrella package connecting mechanism passes through the through hole (20) and is bound to the umbrella rocket.

3. The low altitude parachute deployment apparatus of claim 2 wherein, The ignition head (1) is an electric ignition head, which comprises an ignition head signal input end (10) and an ignition head connecting section (11); The ignition head connecting section (11) is connected with the outer shell threaded hole (18) through threads, and the ignition head signal input end (10) is located outside the outer shell (6) after connection, and is used for receiving the electric signal from the carrier; the ignition head connecting section (11) is in contact with the launching charge (3), and is used for generating sparks to ignite the launching charge (3).

4. The low altitude parachute deployment apparatus of claim 3 wherein, The main body of the launching charge shell (2) is arc-shaped, closely adheres to the inner wall of the front end of the outer shell (6), is hollow inside, and is used for placing the launching charge (3); one end is provided with a cylindrical section opening (13) for cooperating with the elastic gasket (4) to press the launching charge (3); the other end is provided with a launching charge shell threaded hole (12) in the center for connecting the ignition head.

5. The low altitude parachute deployment apparatus of claim 4 wherein, The elastic gasket (4) is integrally composed of an elastic gasket large-radius cylindrical section (14) and an elastic gasket small-radius cylindrical section (15), the elastic gasket large-radius cylindrical section (14) cooperates with the cylindrical section opening at one end of the launching charge shell (2), one end of the elastic gasket small-radius cylindrical section (15) cooperates with one end of the solid charge column (5), and is used for providing elastic support for the solid charge column (5); the elastic gasket (4) is provided with a plurality of through holes inside, which are used for ensuring that the flame generated by the combustion of the launching charge (3) passes through.

6. The low altitude parachute deployment apparatus of Claim 5 wherein, The charge column (5) is a solid fuel with a cylindrical shape and a star-shaped through hole (16) with twelve angles inside; the charge column (5) is arranged in the outer shell, and the outer surface closely adheres to the inner surface of the outer shell (6).

7. The low altitude parachute deployment apparatus of claim 6 wherein, The pressing charge piece (7) is a cylindrical structure, the outer surface is provided with threads for cooperating with the inner threads at one end of the cylindrical section of the outer shell (6), and the inside of the pressing charge piece (7) is provided with a through hole for the flame generated by the combustion of the charge column (5) to pass through.

8. The low altitude parachute deployment apparatus of claim 7 wherein, The nozzle (8) is convergent-divergent streamline type as a whole, the nozzle connecting section (17) of the nozzle (8) is provided with threads for cooperating with the connecting section threads of the outer shell (6), and the sealing piece (9) at the throat of the nozzle (8) is made of rubber, which is used for preventing the charge column from being damp after contacting with the air.

9. The low altitude parachute deployment apparatus of claim 8 wherein, The umbrella bag connecting mechanism further comprises a fireproof ring (24) and a fireproof rope II (25); The fireproof ring (24) has an inner diameter larger than the outer diameter of the shell (6), and is composed of thick and thin arc segments arranged alternately. The fireproof rope I (23) has four, and the boss (19) on the shell (6) has four. Each fireproof rope I (23) has one end passing through the through hole (20) and being bound to the umbrella rocket, and the other end being connected to the four large-radius ring segments of the fireproof ring (24), i.e. thick ring. The fireproof rope II (25) is composed of four sub-ropes and one main rope. One end of the main rope is connected to the four sub-ropes, and the other end is connected to the parachute bag (26). The four sub-ropes are bound to the four small-radius arcs of the fireproof ring (24).

10. A method of deploying a parachute using the low altitude parachute deployment system of any one of claims 1-9, wherein, After receiving the electric signal, the ignition head (1) is activated to generate a high-temperature spark in a microsecond level, igniting the preloaded launch powder (3) in the shell (6). When the launch powder (3) is ignited, the high-temperature flame released forms a directional flame beam through the through hole in the center of the elastic pad (14), igniting the propellant column (5) by inertia. The high-temperature and high-pressure gas generated by the burning of the propellant column (5) is guided through the internal star-shaped through hole and then sprayed out at high speed from the bottom nozzle (8), forming a reaction force thrust to instantaneously launch the entire propulsion system. After the parachute is completely pulled out, the umbrella rocket will still output a pulling force to the fireproof rope. Once the pulling force exceeds the limit of the pre-set weakened arc segment on the fireproof ring, the fireproof ring will break, and the umbrella rocket and the parachute bag will separate.

Images