Solid rocket engine and method of manufacturing the same

Abstract

The present application relates to the field of solid rocket engine, disclose a kind of solid rocket engine and its manufacturing method, casing is set on inner bushing assembly, wherein, inner bushing assembly is detachable structure, solid propellant grain is set in the cylindrical structure of inner bushing assembly, one end of inner bushing assembly is front head section, the other end is nozzle section;The front head section is provided with an ignition interface, the igniter is assembled in the ignition interface, the nozzle plug is assembled in the nozzle section, the device structure is simple, greatly simplifies the number of engine parts and manufacturing process, the whole preparation process also does not involve complex process steps, yield is high, greatly improve the control of performance precision.

Description

Technical Field

[0001] This invention relates to the field of solid rocket engines, specifically to a solid rocket engine and its manufacturing method. Background Technology

[0002] Solid rocket motors are commonly used as propulsion systems for micro- and small aerial vehicles (MAVs) to achieve a certain initial flight speed and meet requirements for flight stability and long range. The cost of the propulsion system directly impacts the large-scale application of MAVs. With the development of diversified missions, multi-platform deployments, and clustering of MAVs, there is a growing demand for low-cost and rapid manufacturing of solid rocket motors.

[0003] Solid rocket motors typically consist of a combustion chamber shell, insulation layer, liner, propellant grains, nozzle shell, throat liner, convergent section, divergent section, nozzle plug, and ignition device. Their manufacturing process involves numerous steps, including machining parts made of different materials, bonding the insulation layer, loading propellant, assembling the nozzle, assembling components, and sealing testing. Solid rocket motors are characterized by short operating times and high performance precision requirements, making them particularly sensitive to errors in component machining and assembly. Therefore, existing solid rocket motor design and manufacturing methods suffer from drawbacks such as numerous components, low manufacturing efficiency, and difficulty in controlling performance precision, resulting in high product costs and unsuitability for large-scale, rapid manufacturing. Summary of the Invention

[0004] In order to overcome the defects of the existing technology, the purpose of this invention is to provide a solid rocket engine and its manufacturing method, so as to solve the technical problems of numerous technical components, low manufacturing efficiency, difficulty in controlling performance precision, high product cost, and unsuitability for mass production and rapid manufacturing.

[0005] This invention is achieved through the following technical solution:

[0006] A solid rocket motor includes an outer shell, an inner liner assembly, a solid propellant grain, an igniter, and a nozzle plug. The outer shell is fitted onto the inner liner assembly, the middle section of which is a cylindrical structure, and the solid propellant grain is fitted inside the cylindrical structure of the inner liner assembly. One end of the inner liner assembly is a front end cap, and the other end is a nozzle section. The front end cap is provided with an ignition interface, the igniter is assembled inside the ignition interface, the nozzle plug is assembled inside the nozzle section, and the inner liner assembly is an assembled structure.

[0007] Preferably, the inner liner assembly includes a first inner liner and a second inner liner; the first inner liner and the second inner liner are assembled relative to each other to form a cylindrical cavity structure with openings at both ends.

[0008] Furthermore, the first inner liner includes a first inner liner front end cap section, a first inner liner semi-cylindrical section, and a first inner liner nozzle section; the first inner liner front end cap section is located at one end of the first inner liner semi-cylindrical section, and the first inner liner nozzle section is located at the other end of the first inner liner semi-cylindrical section. Several positioning bosses are provided at the mating surfaces of the first inner liner front end cap section and the first inner liner nozzle section for positioning and docking with the second inner liner.

[0009] Furthermore, the front end cap of the first inner liner is provided with a first igniter interface, which is used to form an ignition interface after docking with the second inner liner.

[0010] Furthermore, the second inner liner includes a front end cap section, a semi-cylindrical section, and a nozzle section; the front end cap section is located at one end of the semi-cylindrical section, and the nozzle section is located at the other end; a plurality of positioning holes are provided at the mating surfaces of the front end cap section and the nozzle section for positioning and docking with the first inner liner.

[0011] Furthermore, the front end cap of the second inner liner is provided with a second igniter interface, which is used to form an ignition interface after docking with the first inner liner.

[0012] Furthermore, the opposing surfaces of the first and second inner bushings are assembled by applying adhesive to form an inner bushing assembly.

[0013] Furthermore, the outer walls of both the first and second inner bushings are provided with adhesive grooves to enhance adhesion to the outer shell.

[0014] Preferably, the ignition interface is located at the center of the end face of the front end cap section.

[0015] A method for manufacturing a solid rocket motor, based on the solid rocket motor described above, includes the following steps:

[0016] The outer shell is formed by metal processing or the composite material shell is formed by fiber winding or lay-up curing.

[0017] The inner bushing assembly is obtained by compression molding using a mold according to a resin-based composite material compression molding process.

[0018] The outer cylindrical surface of the solid propellant grain is coated with adhesive and assembled into any one of the assemblies of the inner liner assembly;

[0019] The mating surfaces and inner cavity surfaces of the inner liner assembly are coated with one or two adhesives and then joined together to obtain an inner liner assembly containing solid propellant grains.

[0020] The outer cylindrical surface of the inner bushing assembly is coated with one or two adhesives;

[0021] The outer shell is assembled onto the inner bushing assembly coated with adhesive;

[0022] The igniter and nozzle plug are respectively assembled into the center hole of the front end cap section and the mating part of the nozzle section of the inner liner assembly to complete the manufacturing of the solid rocket motor.

[0023] Compared with the prior art, the present invention has the following beneficial technical effects:

[0024] This invention provides a solid rocket motor in which an outer shell is fitted onto an inner liner assembly. The inner liner assembly is a detachable structure, and a solid propellant grain is fitted inside the cylindrical structure of the inner liner assembly. One end of the inner liner assembly is a front end cap section, and the other end is a nozzle section. The front end cap section is provided with an ignition interface, and the igniter is assembled inside the ignition interface. The nozzle plug is assembled inside the nozzle section. This device has a simple structure, greatly simplifying the number of engine parts and the manufacturing process. The entire preparation process does not involve complex process steps, resulting in a high yield and significantly improving the control of performance accuracy.

[0025] Furthermore, the inner liner assembly includes a first inner liner and a second inner liner; the first inner liner and the second inner liner are assembled relative to each other to form a cylindrical cavity structure with openings at both ends. By splitting the inner liner assembly in half to form the first inner liner and the second inner liner, the assembly flexibility of the inner liner assembly is improved.

[0026] Furthermore, the opposing surfaces of the first and second inner bushings are assembled by applying adhesive to form an inner bushing assembly, which improves the tightness and sealing of the first and second inner bushings after assembly, preventing them from falling off and leaking air at the assembly surface, thus affecting engine operation.

[0027] Furthermore, the ignition port is located at the center of the front end cap, which enables uniform and rapid ignition of the solid propellant grain combustion surface.

[0028] This invention provides a solid rocket motor that uses compression molding to form complex-shaped parts, making it easier to ensure molding accuracy. The mold can be designed once and mass production can be achieved, effectively simplifying the number of engine parts and the manufacturing process, increasing the yield rate, enabling rapid mass production, and reducing product costs. Attached Figure Description

[0029] Figure 1 This is a schematic diagram of the internal structure of the solid rocket motor in this invention;

[0030] Figure 2 This is an internal sectional view of the inner bushing assembly in this invention;

[0031] Figure 3 This is a schematic diagram of the structure of the first inner bushing and the second inner bushing in this invention;

[0032] Figure 4 This is a schematic diagram showing the assembly sequence of the solid rocket motor components in this invention.

[0033] In the diagram: 1-Outer shell; 2-Inner liner assembly; 3-Solid propellant grain; 4-Igniter; 5-Nozzle plug; 21-First inner liner; 22-Second inner liner; 23-Adhesive groove; 211-First inner liner front end cap section; 212-First inner liner semi-cylindrical section; 213-First inner liner nozzle section; 221-Second inner liner front end cap section; 222-Second inner liner semi-cylindrical section; 223-Second inner liner nozzle section; 2111-First igniter interface; 2112-Positioning boss; 2211-Second igniter interface; 2212-Positioning hole. Detailed Implementation

[0034] To enable those skilled in the art to better understand the present invention, the technical solutions of the present invention will be clearly and completely described below with reference to the accompanying drawings of the embodiments of the present invention. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort should fall within the scope of protection of the present invention.

[0035] It should be noted that the terms "first," "second," etc., in the specification, claims, and accompanying drawings of this invention are used to distinguish similar objects and are not necessarily used to describe a specific order or sequence. It should be understood that such data can be interchanged where appropriate so that the embodiments of the invention described herein can be implemented in orders other than those illustrated or described herein. Furthermore, the terms "comprising" and "having," and any variations thereof, are intended to cover a non-exclusive inclusion; for example, a process, method, system, product, or apparatus that comprises a series of steps or units is not necessarily limited to those steps or units explicitly listed, but may include other steps or units not explicitly listed or inherent to such processes, methods, products, or apparatus.

[0036] The present invention will now be described in further detail with reference to the accompanying drawings:

[0037] The purpose of this invention is to provide a solid rocket engine and its manufacturing method to solve the technical problems of numerous components, low manufacturing efficiency, difficulty in controlling performance precision, high product cost, and unsuitability for mass production and rapid manufacturing.

[0038] Specifically, according to Figure 1As shown, the solid rocket motor includes an outer shell 1, an inner liner assembly 2, a solid propellant grain 3, an igniter 4, and a nozzle plug 5. The outer shell 1 is fitted onto the inner liner assembly 2. The middle section of the inner liner assembly 2 is a cylindrical structure, and the solid propellant grain 3 is fitted inside the cylindrical structure of the inner liner assembly 2. One end of the inner liner assembly 2 is a front end cap section, and the other end is a nozzle section. The front end cap section is provided with an ignition interface, the igniter 4 is assembled inside the ignition interface, and the nozzle plug 5 is assembled inside the nozzle section. The inner liner assembly 2 is an assembled structure.

[0039] Specifically, according to Figure 2 As shown, the inner liner assembly 2 includes a first inner liner 21 and a second inner liner 22; the first inner liner 21 and the second inner liner 22 are assembled relative to each other to form a cylindrical cavity structure with openings at both ends.

[0040] Specifically, according to Figure 3 As shown, the first inner liner 21 includes a first inner liner front end cap section 211, a first inner liner semi-cylindrical section 212, and a first inner liner nozzle section 213. The first inner liner front end cap section 211 is located at one end of the first inner liner semi-cylindrical section 212, and the first inner liner nozzle section 213 is located at the other end of the first inner liner semi-cylindrical section 212. Several positioning bosses 2112 are provided at the mating surfaces of the first inner liner front end cap section 211 and the first inner liner nozzle section 213 for positioning and docking with the second inner liner 22.

[0041] The first inner liner front end cap section 211 is provided with a first igniter interface 2111, which is used to form an ignition interface after docking with the second inner liner 22.

[0042] Specifically, according to Figure 3 As shown, the second inner liner 22 includes a second inner liner front end cap section 221, a second inner liner semi-cylindrical section 222, and a second inner liner nozzle section 223. The second inner liner front end cap section 221 is located at one end of the second inner liner semi-cylindrical section 222, and the second inner liner nozzle section 223 is located at the other end of the second inner liner semi-cylindrical section 222. A plurality of positioning holes 2212 are provided at the mating surface of the second inner liner front end cap section 221 and the second inner liner nozzle section 223 for positioning and docking with the first inner liner 21.

[0043] The second inner liner front end cap section 221 is provided with a second igniter interface 2211, which is used to form an ignition interface after docking with the first inner liner 21.

[0044] The opposing surfaces of the first inner sleeve 21 and the second inner sleeve 22 are assembled by applying adhesive to form the inner sleeve assembly 2.

[0045] In this invention, the outer walls of the first inner sleeve 21 and the second inner sleeve 22 are provided with adhesive grooves 23 to enhance the adhesion to the outer shell 1.

[0046] Specifically, the ignition interface is located at the center of the front end cap section.

[0047] This invention also provides a method for manufacturing a solid rocket motor, based on the solid rocket motor described above, comprising the following steps:

[0048] The outer shell 1 is formed by metal processing or the composite material shell is formed by fiber winding or lay-up curing.

[0049] The first inner sleeve 21 and the second inner sleeve 22 are respectively molded using a mold according to the resin-based composite material compression molding process.

[0050] The outer cylindrical surface of the solid propellant grain is coated with adhesive and assembled inside the first inner sleeve 21 or the second inner sleeve 22.

[0051] The mating surfaces of the first inner sleeve 21 and the second inner sleeve 22 and the inner cavity surface are coated with one or two adhesives and then joined together to obtain an inner sleeve assembly 2 containing a solid propellant grain inside.

[0052] Apply one or two adhesives to the outer cylindrical surface of the inner bushing assembly 2;

[0053] The outer shell 1 is assembled onto the inner bushing assembly 2 coated with adhesive;

[0054] The igniter 4 and the nozzle plug 5 are respectively assembled into the center hole of the front end cap section and the mating part of the nozzle section of the inner liner assembly to complete the manufacturing of the solid rocket motor.

[0055] according to Figure 4 As shown, the assembly process of the solid rocket motor provided by this invention is as follows:

[0056] Step 1: Split the first inner liner 21 and the second inner liner 22 in half;

[0057] Step 2: Assemble the solid propellant grains into the first inner sleeve 21 and the second inner sleeve 22, combining them into one unit;

[0058] Step 3: The outer shell 1 is assembled onto the inner bushing assembly 2;

[0059] Step 4: Assemble the igniter 4 and the nozzle plug 5 into the center hole of the front end cap section and the mating part of the nozzle section of the inner bushing assembly, respectively.

[0060] In this invention, the outer shell 1 is a thin-walled cylindrical structure capable of withstanding the high-pressure load of internal combustion gas transmission during engine operation. The inner bushing assembly 2 is fitted inside the outer shell 1 and is a cylindrical cavity with open ends, formed by bonding a first inner bushing 21 and a second inner bushing 22 together. It is divided into a front end cap section, a cylindrical section, and a nozzle section. The first inner bushing 21 and the second inner bushing 22 are semi-cylindrical cavities with open ends. The first inner bushing 21 has several positioning bosses, and the second inner bushing 22 has several positioning holes. The nozzle plug 5 is adhered to the nozzle section of the inner bushing assembly. Under a certain ignition pressure, the plug can be quickly opened and ejected with the airflow. The outer shell 1 is made of metal or continuous fiber-reinforced composite material. The inner bushing assembly 2 is a resin-based composite material containing one or more fibers, manufactured using a molding process. The inner bushing assembly 2 is made of a high-silica phenolic composite material.

[0061] In summary, this invention provides a solid rocket motor and its manufacturing method. An outer shell is fitted onto an inner liner assembly, wherein the inner liner assembly is a detachable structure. Solid propellant grains are fitted inside the cylindrical structure of the inner liner assembly. One end of the inner liner assembly is a front end cap section, and the other end is a nozzle section. The front end cap section is provided with an ignition interface, and the igniter is assembled inside the ignition interface. The nozzle plug is assembled inside the nozzle section. This device has a simple structure, greatly simplifying the number of engine components and the manufacturing process. The entire preparation process does not involve complex technological steps, resulting in a high yield and significantly improving the control of performance precision.

[0062] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention and not to limit it. Although the present invention has been described in detail with reference to the above embodiments, those skilled in the art should understand that modifications or equivalent substitutions can still be made to the specific implementation of the present invention. Any modifications or equivalent substitutions that do not depart from the spirit and scope of the present invention should be covered within the scope of protection of the claims of the present invention.

Claims

1. A solid rocket motor, characterized in that, It includes an outer shell (1), an inner liner assembly (2), a solid propellant grain (3), an igniter (4), and a nozzle plug (5); the outer shell (1) is fitted onto the inner liner assembly (2), the middle section of the inner liner assembly (2) is a cylindrical structure, and the solid propellant grain (3) is fitted inside the cylindrical structure of the inner liner assembly (2); one end of the inner liner assembly (2) is a front end cap section, and the other end is a nozzle section; the front end cap section is provided with an ignition interface, the igniter (4) is assembled inside the ignition interface, the nozzle plug (5) is assembled inside the nozzle section, and the inner liner assembly (2) is an assembled structure; The inner liner assembly (2) includes a first inner liner (21) and a second inner liner (22); the first inner liner (21) and the second inner liner (22) are assembled relative to each other to form a columnar cavity structure with openings at both ends; The first inner liner (21) includes a first inner liner front end cap section (211), a first inner liner semi-cylindrical section (212), and a first inner liner nozzle section (213). The first inner liner front end cap section (211) is located at one end of the first inner liner semi-cylindrical section (212), and the first inner liner nozzle section (213) is located at the other end of the first inner liner semi-cylindrical section (212). Several positioning bosses (2112) are provided at the mating surfaces of the first inner liner front end cap section (211) and the first inner liner nozzle section (213) for positioning and docking with the second inner liner (22).

2. A solid rocket motor according to claim 1, characterized in that, The first inner liner front end cap section (211) is provided with a first igniter interface (2111), which is used to form an ignition interface after docking with the second inner liner (22).

3. A solid rocket motor according to claim 1, characterized in that, The second inner liner (22) includes a second inner liner front end cap section (221), a second inner liner semi-cylindrical section (222), and a second inner liner nozzle section (223). The second inner liner front end cap section (221) is located at one end of the second inner liner semi-cylindrical section (222), and the second inner liner nozzle section (223) is located at the other end of the second inner liner semi-cylindrical section (222). Several positioning holes (2212) are provided at the mating surfaces of the second inner liner front end cap section (221) and the second inner liner nozzle section (223) for positioning and docking with the first inner liner (21).

4. A solid rocket motor according to claim 3, characterized in that, The second inner liner front end cap section (221) is provided with a second igniter interface (2211), which is used to form an ignition interface after docking with the first inner liner (21).

5. A solid rocket motor according to claim 1, characterized in that, The opposing surfaces of the first inner sleeve (21) and the second inner sleeve (22) are assembled by applying adhesive to form an inner sleeve assembly (2).

6. A solid rocket motor according to claim 1, characterized in that, The outer walls of the first inner sleeve (21) and the second inner sleeve (22) are provided with adhesive grooves (23) to enhance the adhesion to the outer shell (1).

7. A solid rocket motor according to claim 1, characterized in that, The ignition interface is located at the center of the end face of the front end cap section.

8. A method for manufacturing a solid rocket motor, based on the solid rocket motor according to any one of claims 1-7, characterized in that, Includes the following steps: The outer shell (1) is formed by metal processing or the composite material shell is formed by fiber winding or lay-up curing; The inner bushing assembly (2) is obtained by compression molding using a mold according to the resin-based composite material compression molding process; The outer cylindrical surface of the solid propellant grain is coated with adhesive and assembled into any one of the assemblies of the inner liner assembly (2); The mating surfaces and inner cavity surfaces of the inner liner assembly (2) are coated with one or two adhesives to obtain an inner liner assembly (2) containing solid propellant grains. The outer cylindrical surface of the inner bushing assembly (2) is coated with one or two adhesives; The outer shell (1) is assembled onto the inner bushing assembly (2) coated with adhesive; The igniter (4) and the nozzle plug (5) are respectively assembled into the center hole of the front end section of the inner liner assembly and the mating part of the nozzle section to complete the manufacturing of the solid rocket engine.

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