Impact attenuation structure for on-board pyrotechnic devices

Abstract

The application provides a shock-attenuating structure of an on-board pyrotechnic device, which comprises an upper connecting piece, a transition piece and a lower connecting piece, the transition piece is arranged between the upper connecting piece and the lower connecting piece, the outer side surface of the upper connecting piece is attached to the upper inner surface of the transition piece and is fixedly connected through a shock-absorbing connecting assembly, the lower connecting piece is formed with an inner recessed mounting groove, the lower part of the transition piece extends into the inner recessed mounting groove of the lower connecting piece, and an energy-absorbing interlayer is arranged between the outer side wall of the transition piece and the inner side wall of the mounting groove, and the lower connecting piece, the energy-absorbing interlayer and the transition piece are fixedly connected through the shock-absorbing connecting assembly. The application aims at the limitation of small installation structure design space of the on-board pyrotechnic device, increases the transmission path of the impact load by designing the split type upper connecting piece, the transition piece and the lower connecting piece, and changes the mechanical impedance in the impact load transmission process.

Description

Technical Field

[0001] This invention belongs to the field of spacecraft structure technology, specifically, it relates to an impact-reducing structure for an onboard pyrotechnic device. Background Technology

[0002] The impact load generated by the detonation and unlocking of onboard pyrotechnic devices is characterized by its instantaneous, high-frequency, and high-magnitude nature. It represents the most severe load experienced by any single onboard unit and can easily damage impact-sensitive components such as internal electronic parts and crystal oscillators. To minimize the damage effect of the impact on the unit, impact-sensitive units are typically installed far from the pyrotechnic devices during unit layout. However, when there are many onboard pyrotechnic devices, multiple impact sources, and limited space for unit layout, it is no longer possible to completely isolate sensitive units from the pyrotechnic sources. Therefore, it is necessary to design impact-reducing structures for the pyrotechnic devices to reduce the magnitude of the impact transmitted to the unit. Currently, impact-reducing devices or structures for satellites can be divided into two categories: The first category involves designing shock-reducing structures at the spacecraft-launcher interface. For example, Chinese patent application CN203512061U discloses a shock-reducing structure suitable for small spacecraft, which adds a connecting frame between the small spacecraft and the launch vehicle, and improves the overall impact environment of the small spacecraft through the buffering effect of the damping layer; Chinese patent application CN104058107A discloses a spacecraft-launcher separation shock-reducing connection device, which also designs a shock-reducing device at the spacecraft-launcher interface and reduces impact by adding buffer holes; Chinese patent application CN106864775A discloses a spacecraft payload shock-reducing device, which also designs a ring structure at the spacecraft-launcher interface to achieve the purpose of shock reduction. Paper: Optimization Design of Shock-Reducing Ring Structure for Spacecraft-Launcher Separation (Journal of Astronautics, 2022, 43(7):946-956), designs a staggered ring structure at the spacecraft-launcher interface, and obtains the optimal shock-reducing structure through the optimization design of the ring structure parameters.

[0003] The second type involves designing shock absorbers at individual equipment locations, which absorb impact energy through the deformation of energy storage elements to achieve shock reduction. For example, the paper "Research on Flat Foam Aluminum Shock Absorbers for Deployable Satellite Accessories" (Strength and Environment, 2018, 45(1): 50-56) uses the deformation of aluminum foam to absorb energy and achieve shock reduction. Chinese patent application document with publication number CN204477508U discloses a three-way shock absorber for impact protection of ship pipelines, which absorbs energy through the deformation of springs to achieve shock reduction.

[0004] For pyrotechnic devices on spacecraft, both of the aforementioned shock-absorbing devices or structures have limitations, as detailed below: The first type involves designing impact-reducing devices at the spacecraft-rocket interface. These devices offer ample design space and complex structures, whereas the installation space for onboard pyrotechnic devices is often limited. Therefore, impact-reducing structures at the spacecraft-rocket interface cannot be directly applied to other onboard pyrotechnic devices.

[0005] The second type of shock absorber absorbs energy through the deformation of the energy storage element. It has weak stiffness, which affects the installation accuracy of the components and amplifies the response level of low-frequency sinusoidal vibration.

[0006] Therefore, it is necessary to design a pyrotechnic device impact reduction structure that is compact in form, has moderate load-bearing capacity, and good rigidity. Summary of the Invention

[0007] To address the shortcomings of existing technologies, the purpose of this invention is to provide an impact-reducing structure for on-board pyrotechnic devices.

[0008] According to the present invention, a shock-reducing structure for an on-board pyrotechnic device includes an upper connector, a transition member, and a lower connector, wherein the transition member is disposed between the upper connector and the lower connector. The outer side of the upper connector fits against the upper inner surface of the transition piece and is fixedly connected by a shock-absorbing connection assembly. The lower connector has a recessed mounting groove, the lower part of the transition piece extends into the recessed mounting groove of the lower connector, and an energy-absorbing interlayer is provided between the outer side wall of the transition piece and the inner side wall of the mounting groove. The lower connector, the energy-absorbing interlayer, and the transition piece are fixedly connected by a shock-absorbing connection assembly.

[0009] In one feasible implementation, the top surface of the upper connector is provided with threaded holes and locating pin holes for assembly with the on-board pyrotechnic device.

[0010] In one feasible implementation, the shock-absorbing connection assembly includes a flat washer, a spring washer, and a screw; In the connection structure of the upper connector and the transition piece, the upper connector has a threaded hole on its side and the transition piece has a through hole on its upper side; the screw passes through the spring washer, the flat washer, and the through hole on the transition piece in sequence from the outside to the inside, and is then screwed into the threaded hole on the side of the upper connector. In the connection structure of the lower connector and the transition piece, the outer side wall of the transition piece is provided with a threaded hole, and the side wall of the mounting groove of the lower connector is provided with a through hole; the screw passes through the spring washer, the flat washer, and the through hole on the side wall of the mounting groove of the lower connector in sequence from the outside to the inside, and then is screwed into the threaded hole on the outer side wall of the transition piece.

[0011] In one feasible implementation, the transition member includes an upper lug connected to the upper connector and a lower column connected to the lower connector, and the transition member is a hollow structure.

[0012] In one feasible implementation, the lower connector includes four sets of hollow square rods, each of which is provided with a recessed mounting groove. The transition member has four sets of lower columns, and the four sets of lower columns correspond one-to-one with the four sets of hollow square rods and are inserted into each other.

[0013] In one feasible implementation, the upper lug is provided with three through holes arranged in a triangular shape.

[0014] In one feasible implementation, the four sets of lower columns form a rectangular structure, and any two adjacent lower columns in any set are connected by a perforated sidewall.

[0015] In one feasible implementation, the sidewalls of the lower column and the inner wall of the recessed mounting groove of the hollow square rod are connected by at least one set of shock-absorbing connection components.

[0016] In one feasible implementation, the energy-absorbing interlayer includes a rubber pad.

[0017] In one feasible implementation, the bottom of the lower connector is provided with a flange structure that connects to the celestial structure.

[0018] Compared with the prior art, the present invention has the following beneficial effects: 1. This invention addresses the limitation of limited space in the installation structure design of on-board pyrotechnic devices by designing a split upper connector, transition component, and lower connector, thereby increasing the transmission path of impact loads and changing the mechanical resistance during the transmission of impact loads.

[0019] 2. By increasing the connection interface between the upper connector and the transition piece, and the connection interface between the transition piece and the lower connector, the present invention changes the mechanical resistance in the process of impact load transmission, thereby attenuating the impact load; the rubber pad between the transition piece and the lower connector plays a buffering role, further increasing the attenuation of the impact load.

[0020] 3. The present invention has a compact structure and simple form, and the structure of each connecting part is simple, easy to process and form, and the assembly form is simple, which facilitates the promotion of models. It can achieve the function of shock reduction without causing the low-frequency sinusoidal vibration response of the components to be amplified. Attached Figure Description

[0021] Other features, objects, and advantages of the present invention will become more apparent from the following detailed description of non-limiting embodiments with reference to the accompanying drawings: Figure 1 This is a schematic diagram illustrating the impact reduction structure of the on-board pyrotechnic device, which is the main feature of this invention. Figure 2 This is a schematic diagram illustrating the connection of the upper connector and the transition piece, which are the main components of this invention. Figure 3 This is a schematic diagram illustrating the connection of the transition piece and the lower connecting piece, which are the main components of this invention.

[0022] Reference numerals: 1. Upper connector; 2. Transition piece; 3. Lower connector; 4. Rubber pad; 5. Flat washer; 6. Spring washer; 7. Screw. Detailed Implementation

[0023] The present invention will now be described in detail with reference to specific embodiments. These embodiments will help those skilled in the art to further understand the present invention, but do not limit the invention in any way. It should be noted that those skilled in the art can make several changes and improvements without departing from the concept of the present invention. These all fall within the protection scope of the present invention.

[0024] like Figures 1 to 3 As shown, the impact-reducing structure of an on-board pyrotechnic device according to the present invention includes an upper connector 1, a transition member 2, and a lower connector 3, with the transition member 2 disposed between the upper connector 1 and the lower connector 3. The outer surface of the upper connector 1 is fitted with the upper inner surface of the transition member 2 and is fixedly connected by a shock-absorbing connecting assembly. A recessed mounting groove is formed on the lower connector 3, and the lower part of the transition member 2 extends into the recessed mounting groove of the lower connector 3. An energy-absorbing interlayer is provided between the outer side wall of the transition member 2 and the inner side wall of the mounting groove. The lower connector 3, the energy-absorbing interlayer, and the transition member 2 are fixedly connected by the shock-absorbing connecting assembly.

[0025] The technical solution of this application changes the mechanical impedance of the impact load transmission process by adding connection interfaces. The connection interface between the upper connector 1 and the transition piece 2, and the connection interface between the transition piece 2 and the lower connector 3, change the mechanical impedance of the impact load transmission process and attenuate the impact load; the energy-absorbing interlayer between the transition piece 2 and the lower connector 3 acts as a buffer, further increasing the attenuation of the impact load.

[0026] The upper connector 1, transition component 2, and lower connector 3 of the technical solution of this application are all modular designs, which can be adapted to various types of pyrotechnic devices without changing the main structure.

[0027] Specifically, the upper connector 1 has a rectangular structure, and its top surface has threaded holes and locating pin holes for assembly with the on-board pyrotechnic device. The transition piece 2 has a hollow rectangular frame structure when viewed from above. The lower connector 3 includes four lower columns, which are located at the four corners of the rectangle.

[0028] In one feasible implementation, the shock-absorbing connection assembly includes a flat washer 5, a spring washer 6, and a screw 7. In this application, the screw 7 is preferably an internal hexagon head screw.

[0029] In the connection structure of the upper connector 1 and the transition piece 2: the upper connector 1 has a threaded hole on its side, and the transition piece 2 has a through hole on its upper side. The screw 7 passes through the spring washer 6, the flat washer 5, and the through hole on the transition piece 2 in sequence from the outside to the inside, and is then screwed into the threaded hole on the side of the upper connector 1. Furthermore, the shock-absorbing connection assembly has one or more sets of [specific components] on each of the four peripheral sides of the upper connector 1. Even further, the transition piece 2 includes an upper lug connected to the upper connector 1 and a lower column connected to the lower connector 3, and the transition piece 2 is a hollow structure.

[0030] In a preferred embodiment, one upper lug is provided on each of the four peripheral sidewalls of the transition member 2, forming an installation space. The lower part of the upper connector 1 extends into the installation space formed by the four upper lugs, and the inner walls of the four upper lugs respectively abut against the outer walls of the corresponding upper connector 1. Each upper lug is connected to the outer wall of the corresponding upper connector 1 through a shock-absorbing connecting assembly. Furthermore, three through holes arranged in a triangular pattern are provided on the upper lugs. Each through hole is matched with a set of shock-absorbing connecting assemblies, improving the reliability of the connection.

[0031] In a preferred embodiment, four sets of lower columns form a rectangular structure, and any two adjacent lower columns in any set are connected by a perforated sidewall. In the connection structure between the lower connector 3 and the transition piece 2, the outer sidewall of the transition piece 2 is provided with a threaded hole, and the sidewall of the mounting groove of the lower connector 3 is provided with a through hole; the screw 7 passes through the spring washer 6, the flat washer 5, and the through hole on the sidewall of the mounting groove of the lower connector 3 in sequence from the outside to the inside, and then is screwed into the threaded hole on the outer sidewall of the transition piece 2.

[0032] In one feasible embodiment, the lower connector 3 includes four sets of hollow square rods, each of which has a recessed mounting groove. The sidewall of each recessed mounting groove is open towards the center of the four sets of hollow square rods. The transition piece 2 has four sets of lower columns, each corresponding to and inserted into one of the four sets of hollow square rods. The energy-absorbing interlayer includes rubber pads 4, which are placed between the outer sidewall of the lower column and the inner sidewall of the recessed mounting groove. The sidewalls of the lower column and the inner wall of the recessed mounting groove of the hollow square rod are connected by at least one set of shock-absorbing connecting components. The bottom of the lower connector 3 has a flanged structure that connects to the celestial structure.

[0033] In a preferred embodiment, the top surface of the upper connector 1 is 10mm thick, and 4-M5 threaded holes and Φ8mm pin holes provide mounting and positioning holes for the on-board pyrotechnic device. Each of the four peripheral sides has 3-M5 threaded holes for fastening connection with the transition piece 2.

[0034] The upper lugs of the transition piece 2 are provided with 3-Φ5.5mm through holes, which are fastened to the upper connector 1. The lower column of the transition piece 2 is provided with 3-M5 threaded holes, which are fastened to the lower connector 3. The middle area of ​​the transition piece 2 is hollowed out, which extends the transmission path of the pyrotechnic impact and changes the mechanical resistance of the connection interface.

[0035] The energy-absorbing interlayer is 5mm thick and comes in two specifications, each providing 2 through holes of Φ5.5mm and one through hole of Φ5.5mm.

[0036] The column part of the lower connector 3 is a hollow square rod with a wall thickness of 3mm. The upper side wall of the four sets of square rods is provided with 3-Φ5.5mm through holes. The middle part is fastened to the transition piece 2 through two types of rubber pads 4. The bottom flange of the lower connector 3 provides an installation interface with the star structure.

[0037] In the description of this application, it should be understood that the terms "upper", "lower", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this application and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this application.

[0038] Specific embodiments of the present invention have been described above. It should be understood that the present invention is not limited to the specific embodiments described above, and those skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the essence of the present invention. Unless otherwise specified, the embodiments and features described in this application can be arbitrarily combined with each other.

Claims

1. An impact-reducing structure for an on-board pyrotechnic device, characterized in that, It includes an upper connector (1), a transition piece (2) and a lower connector (3), wherein the transition piece (2) is disposed between the upper connector (1) and the lower connector (3); The outer side of the upper connector (1) is attached to the upper inner surface of the transition piece (2) and is fixedly connected by a shock-absorbing connection assembly; The lower connector (3) has a recessed mounting groove, the lower part of the transition piece (2) extends into the recessed mounting groove of the lower connector (3), and an energy-absorbing interlayer is provided between the outer side wall of the transition piece (2) and the inner side wall of the mounting groove. The lower connector (3), the energy-absorbing interlayer and the transition piece (2) are fixedly connected by a shock-absorbing connection assembly.

2. The impact-reducing structure of the on-board pyrotechnic device according to claim 1, characterized in that, The top surface of the upper connector (1) is provided with threaded holes and positioning pin holes for assembly with the on-board pyrotechnic device.

3. The impact-reducing structure of the on-board pyrotechnic device according to claim 1, characterized in that, The shock-absorbing connection assembly includes a flat washer (5), a spring washer (6), and a screw (7); In the connection structure of the upper connector (1) and the transition piece (2), the upper connector (1) is provided with a threaded hole on its side, and the transition piece (2) is provided with a through hole on its upper side; the screw (7) passes through the spring washer (6), the flat washer (5), and the through hole on the transition piece (2) from the outside to the inside, and then is screwed into the threaded hole on the side of the upper connector (1); In the connection structure of the lower connector (3) and the transition piece (2), the outer side wall of the transition piece (2) is provided with a threaded hole, and the side wall of the mounting groove of the lower connector (3) is provided with a through hole; the screw (7) passes through the spring washer (6), the flat washer (5), and the through hole on the side wall of the mounting groove of the lower connector (3) from the outside to the inside, and then is screwed into the threaded hole on the outer side wall of the transition piece (2).

4. The impact-reducing structure of the on-board pyrotechnic device according to claim 1, characterized in that, The transition piece (2) includes an upper lug connected to the upper connector (1) and a lower column connected to the lower connector (3), and the transition piece (2) is a hollow structure.

5. The impact-reducing structure of the on-board pyrotechnic device according to claim 4, characterized in that, The lower connector (3) includes four sets of hollow square rods, each of which has a recessed mounting groove. The transition piece (2) has four sets of lower columns, and the four sets of lower columns correspond one-to-one with the four sets of hollow square rods and are inserted into each other.

6. The impact-reducing structure of the on-board pyrotechnic device according to claim 4, characterized in that, The upper lug has three through holes arranged in a triangular shape.

7. The impact-reducing structure of the on-board pyrotechnic device according to claim 5, characterized in that, The four sets of lower columns form a rectangular structure, and any two adjacent lower columns in any set are connected by a hollowed-out sidewall.

8. The impact-reducing structure of the on-board pyrotechnic device according to claim 5, characterized in that, The sidewalls of the lower column and the inner wall of the recessed mounting groove of the hollow square rod are all connected by at least one set of shock-absorbing connection components.

9. The impact-reducing structure of the on-board pyrotechnic device according to claim 1, characterized in that, The energy-absorbing interlayer includes a rubber pad (4).

10. The impact-reducing structure of the on-board pyrotechnic device according to claim 1, characterized in that, The bottom of the lower connector (3) is provided with a flange structure that connects to the celestial structure.

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