A lightweight split type centering structure suitable for a sub-caliber dynamic acceleration device

Abstract

The application discloses a light-weight split type centering structure suitable for a sub-caliber dynamic accelerating device and belongs to the technical field of special launching. The application comprises a front centering part, a rear centering part and an adjusting mechanism; the front centering part is composed of a plurality of annular supports with the same structure according to the length of a projectile body and is sequentially sleeved on the projectile body; the rear centering part is connected with the sleeve through a center blind hole; the bottom surface of the center blind hole of the rear centering part abuts against the tail end surface of the projectile body; the adjusting mechanism is composed of a long screw rod and a plurality of nuts; the position of the annular support of the front centering part is adjusted by adjusting the screwing position; the application reduces the proportion of useless projectile support mass in the launching mass; under the condition of the same launching propellant amount, the projectile body obtains a higher speed, and the design index of reducing the launching mass is realized.

Description

Technical Field

[0001] This invention belongs to the field of special launch, specifically relating to a lightweight split-type centering structure suitable for sub-caliber dynamic acceleration devices. Background Technology

[0002] Dynamic acceleration devices are a common type of acceleration device used in special launch technologies. The general approach involves placing the launcher (usually consisting of a projectile and a launching mechanism) into the launch chamber. The propellant gases propel the projectile, giving it an initial velocity. Once the propellant is ignited, the resulting high-temperature gases accelerate the launcher, completing the launch process. Most dynamic acceleration devices are rifling-free and require a sealing ring to enter the launch chamber with the launcher. The sealing ring's tail skirt expands outwards to achieve gas sealing.

[0003] Subcaliber launch is a launch method suitable for projectiles with an outer diameter smaller than the inner diameter of the launch cavity, primarily used to increase launch velocity and range. Projectiles using subcaliber launch must rely on a launching device. After the subcaliber projectile leaves the launch cavity, the projectile and launching device separate, and the diameter of the remaining projectile decreases, significantly increasing its mass per unit cross-sectional area and initial velocity. Conversely, if the projectile and launching device cannot separate smoothly during launch, it will result in additional mass on the projectile, potentially even directly affecting the final test results.

[0004] Currently, sub-caliber launch technology has been combined with dynamic acceleration devices. As one of the main load-bearing components of the sub-caliber projectile, the launch device transfers the energy of the propellant gases to the projectile within the launch chamber, giving the projectile a high initial velocity. In addition, the requirements for the launch device include: ensuring support and proper guidance of the projectile's movement within the launch chamber wall; possessing sufficient strength while maintaining a minimal mass ratio to the projectile; and facilitating assembly with the complete projectile assembly.

[0005] Patent application 2025107310473 discloses "A Lightweight Composite Centering Structure Design Applicable to Sub-caliber Balanced Guns." Its structural design uses threads to connect the projectile to the launching device. This design is simple to manufacture and has low production costs, but its drawback is that the projectile and launching device do not separate in a timely manner. When separation is not timely, the reaction force of air resistance will cause the projectile's aerodynamic shape to become statically unstable, inevitably leading to attitude instability as the flight distance increases. This results in the projectile having a very large angle of attack and yaw before impact, or even striking the target horizontally, failing to achieve normal penetration. Furthermore, this technology requires designing threads on the projectile, which damages the projectile's structure and affects the actual results of penetration tests. Therefore, for sub-caliber launchers of large-caliber dynamic acceleration devices, a launching device that balances lightweight design and structural strength is needed, maintaining high strength at a lower mass while facilitating assembly with the projectile. Summary of the Invention

[0006] This invention proposes a lightweight, split-type centering structure suitable for launching sub-caliber dynamic acceleration devices, in order to solve the problems of thrust transmission and launch stability during the launch process of sub-caliber dynamic acceleration devices with large aspect ratio projectiles, high chamber pressure, and single barrel diameter.

[0007] The technical solution for realizing the present invention is: a lightweight split-type centering structure suitable for sub-caliber dynamic acceleration devices, including a front centering part, a rear centering part, an adjustment mechanism, an air-sealing ring, and a pressure ring.

[0008] The front fixing part is composed of It consists of a lightweight ring-shaped support with weight-reducing grooves. The projectile is fitted into the center holes of each annular support of the front centering part, and the bottom end of the projectile is inserted into the center of the rear centering part; the outer ring wall of the front centering part is in clearance fit with the inner wall of the launch cavity, and the front and rear ends of the front centering part are respectively provided with weight reduction grooves. The front centering part achieves weight reduction by removing three arcs on its outer ring, so that the cross-section of the outer ring is trident-shaped, and a through hole is provided on the connection part between the outer ring and the inner ring of the front centering part.

[0009] The rear centering part is a rotating body with a clearance fit between its outer wall and the inner wall of the launch cavity. The center of the front end face of the rear centering part has a central blind hole for connecting the projectile. The outer ring of the central blind hole has a circular weight-reducing groove. Three threaded blind holes are evenly arranged on the front end face near the outer ring. The bottom end of the rear centering part is a stepped shaft. The stepped shaft pressure ring is connected by threads, and an air-sealing ring is provided between the two.

[0010] The adjustment mechanism consists of three long screws. The front centering part and the rear centering part are connected through the adjustment mechanism. The three long screws pass through the through hole of the front centering part from front to back and engage with the threaded hole of the rear centering part. Nuts are used to axially position the ring bracket.

[0011] Compared with the prior art, the significant advantages of this invention are:

[0012] (1) In this invention, the front and rear centering parts are designed with weight-reducing grooves and the arc-shaped material is removed. Under the premise of ensuring the structural strength of the centering part, the launch mass is reduced and the safety and reliability are improved.

[0013] (2) The front and rear centering parts can quickly separate from the projectile after the projectile hits the target, so as to avoid affecting the projectile's state and ensure the projectile's own ballistic attitude. The distance between the front and rear centering parts supporting the projectile is relatively long and can be adjusted by adjusting the number of ring supports, which plays the role of positioning the projectile, avoiding the machining of threads on the projectile and achieving the purpose of protecting the integrity of the projectile's structure.

[0014] (3) The rear centering part fixes the gas-sealing ring by cooperating with the pressure ring. The outer diameter of the gas-sealing ring is larger than the inner diameter of the inner wall of the launch chamber. The gas-sealing ring relies on the pressure of the gas in the chamber on the curved skirt to make the skirt warp outward and stick to the inner wall of the tube, ensuring the gas-sealing effect and ensuring reliable gas sealing in the chamber of the dynamic acceleration device during the launch process, so as to achieve stable initial velocity of the projectile. Attached Figure Description

[0015] Figure 1 This is a schematic diagram of the overall structure of the present invention (front view).

[0016] Figure 2 This is a schematic diagram of the overall structure of the present invention (side and rear view).

[0017] Figure 3 This is a schematic diagram of the annular support structure of the front centering part of the present invention.

[0018] Figure 4 This is a schematic diagram of the rear centering section of the present invention.

[0019] Figure 5 This is a schematic diagram of the closed-loop structure of the present invention.

[0020] Figure 6 This is a schematic diagram of the pressure ring structure of the present invention.

[0021] Figure 7 This is a schematic diagram illustrating the structural parameters of the present invention.

[0022] Figure 8 These are the structural parameters of the present invention. Annotation diagram

[0023] 1-Front centering section, 2-Projectile body, 3-Adjustment mechanism, 4-Rear centering section, 5-Air-sealing ring, 6-Pressure ring, -Inner diameter of the inner wall of the launch cavity - Outer diameter of the lightweight ring support, d - Inner diameter of the lightweight ring support, L - Spacing between lightweight ring supports -Projectile length, Diameter of the through hole in the front centering part - Lightweight ring support outer ring thickness - Lightweight ring support connection section thickness -Inner ring thickness of the lightweight ring support, m -Screw module - Depth of the blind hole at the center of the rear centering section -Thickness of the bottom of the rear centering section - Thickness of the centering section - The distance the free end of the projectile is allowed to droop. Detailed Implementation

[0024] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only a part of the embodiments of the present invention, and not all of them. Based on the embodiments of the present invention, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the scope of protection of the present invention.

[0025] It should be noted that all directional indications (such as up, down, left, right, front, back, etc.) in the embodiments of the present invention are only used to explain the relative positional relationship and movement of each component in a certain specific posture (as shown in the figure). If the specific posture changes, the directional indication will also change accordingly.

[0026] Furthermore, in this invention, descriptions involving "first," "second," etc., are for descriptive purposes only and should not be construed as indicating or implying their relative importance or implicitly specifying the number of technical features indicated. Thus, a feature defined as "first" or "second" may explicitly or implicitly include at least one of that feature. In the description of this invention, "a plurality of" means at least two, such as two, three, etc., unless otherwise explicitly and specifically defined.

[0027] In this invention, unless otherwise explicitly specified and limited, the terms "connection," "fixing," etc., should be interpreted broadly. For example, "fixing" can mean a fixed connection, a detachable connection, or an integral part; "connection" can mean a mechanical connection or an electrical connection. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0028] Furthermore, the technical solutions of the various embodiments of the present invention can be combined with each other, but only if they are feasible to those skilled in the art. If the combination of technical solutions is contradictory or cannot be implemented, it should be considered that such combination of technical solutions does not exist and is not within the scope of protection claimed by the present invention.

[0029] The following section will further introduce the specific implementation method, as well as the technical difficulties and inventive points of this invention, using this design example as an example.

[0030] Combination Figures 1-8 A lightweight split-type centering structure suitable for sub-caliber dynamic acceleration devices includes a front centering part 1, a rear centering part 4, an adjustment mechanism 3, an air-sealing ring 5, and a pressure ring 6.

[0031] The front fixing part 1 is composed of It consists of a lightweight ring-shaped support with weight-reducing grooves. The projectile 2 is fitted into the center holes of each annular bracket of the front centering part 1, and the bottom end of the projectile 2 is inserted into the center of the rear centering part 4; the outer ring wall of the front centering part 1 is fitted with the inner wall of the launch cavity with clearance; the front end and rear end of the front centering part 1 are respectively provided with weight reduction grooves; the front centering part 1 achieves weight reduction by removing three arcs on its outer ring, so that the cross-section of the outer ring is trident-shaped; a through hole is provided on the connection part between the outer ring and the inner ring of the front centering part 1.

[0032] The rear centering part 4 is a rotating body with a clearance fit between its outer wall and the inner wall of the launch cavity. A central blind hole is opened at the center of the front end face of the rear centering part 4 for connecting the projectile 2. A circular weight-reducing groove is opened on the outer ring of the central blind hole. Three threaded blind holes are evenly arranged on the front end face near the outer ring. The bottom end of the rear centering part 4 is a stepped shaft shape. The stepped shaft pressure ring 6 is connected by threads, and an air-sealing ring 5 is provided between the two.

[0033] The adjustment mechanism 3 consists of three long screws. The front centering part 1 and the rear centering part 4 are connected through the adjustment mechanism 3. The three long screws pass through the through hole of the front centering part 1 from front to back and engage with the threaded hole of the rear centering part 4. Nuts are used to axially position the ring bracket.

[0034] The central axis of the weight-reducing groove in the front centering part 1 coincides with the central axis of the projectile.

[0035] The rotation axes of the three through holes on the front centering part 1 are parallel to the rotation axis of the projectile.

[0036] The front centering part 1 achieves weight reduction by removing three equally spaced arcs on its outer ring, and the central axis of the removed arc portion is parallel to the central axis of the projectile.

[0037] The front centering part 1 and the rear centering part 4 have outer peripheral chamfers on their end faces facing the firing direction.

[0038] The outer diameter of the pressure ring 6 is smaller than the inner diameter of the air-sealing ring 5.

[0039] The air-sealing ring 5 is an annular skirt structure with an outer diameter not less than the inner diameter of the inner wall of the launch cavity. The structure is hollow, and the cross-section on one side is "L" shaped. It is fitted between the pressure ring 6 and the rear centering part 4.

[0040] A design method for a lightweight, split-type centering structure for a sub-caliber dynamic accelerator, comprising the following steps:

[0041] Step 1: Determine the initial parameters of the dynamic acceleration device before its sub-caliber launch test, including: the inner diameter of the launch cavity wall. Lightweight ring support outer diameter The inner diameter d of the lightweight ring-shaped support; the number of lightweight ring-shaped supports. The cross-sectional area of ​​the inner wall of the launch cavity was further determined by the lightweight annular support spacing L, launch overload a, and missile base thrust F. The mass of projectile 2 The length of projectile 2 The diameter of projectile 2 Proceed to step 2.

[0042] Step 2: Determine the total launch mass Based on the given mass of projectile 2 Determine the quality of the pre-centering part 1 and the quality of the centering part 4 , Proceed to step 3.

[0043] Step 3: Determine the structural parameters of the front centering part 1 and adjust the mechanism 3, including: the diameter of the through hole in the front centering part 1. Lightweight ring support outer ring thickness The thickness of the connecting part of the lightweight ring bracket Inner ring thickness of lightweight ring support The screw module m is as follows:

[0044] Step 3-1: Based on the design requirements, as well as the launch overload a and the mass of the front centering unit 1. The inertial force at this time is calculated, which is the working load borne by the screw. , .

[0045] Step 3-2: Based on design requirements and working load Determine the total load :

[0046] To ensure the safety and reliability of the threaded connection, residual preload is used. Then the preload At this time, the total load , ,in For screw stiffness, Let the stiffness of the front centering part 1 be used; for a conservative estimate, Simplified to .

[0047] Step 3-3: Determine the screw module m based on design requirements and total load:

[0048] Tensile stress of the screw It should be less than the allowable stress of the material. , Let be the stress cross-sectional area of ​​the screw, i.e.: Therefore, the screw module m satisfies Rounding up the modulus m gives the diameter of the through hole in the front centering part 1. .

[0049] Steps 3-4: Based on design requirements and total load Determine the inner ring thickness of the lightweight ring support. The shear strength of the inner ring material of the lightweight ring support It should be less than the allowable shear stress of the material. ,Right now Thus, the inner ring thickness of the lightweight annular support is obtained. satisfy Round up to obtain the inner ring thickness of the lightweight ring support. .

[0050] Steps 3-5: Calculate the outer ring thickness of the lightweight ring support based on design requirements and geometric relationships. And the thickness of the connecting part of the lightweight ring support. , .

[0051] Steps 3-6: Pass the screw through the through hole of the front centering part 1, and use nuts to position and tighten it on the front and rear end faces of the lightweight ring bracket.

[0052] Proceed to step 4.

[0053] Step 4: Determine the structural parameters of the rear centering part 4, including: the depth of the threaded blind hole in the rear centering part 4. The thickness of the bottom of the centering part 4 The thickness of the centering part is 4. The details are as follows:

[0054] Step 4-1: Determine the depth of the threaded blind hole in the rear centering part 4 according to the design requirements and geometric relationships. :

[0055] First, according to the inner diameter of the launch cavity specified in the design requirements... Based on the outer diameter D of the lightweight annular support, determine the allowable droop distance of the free end of projectile 2. ,in The working condition of the projectile 2 extending into the center blind hole of the centering part 4 is simplified into a cantilever beam model with one end fixed and the other end free; at this time For the maximum allowable deflection, The formula for calculating maximum deflection can be modified to obtain... ,at this time Where E is the elastic modulus of the projectile material, I is the moment of inertia of the projectile cross section, and P is the equivalent load at the free end. This is the distance from the top of the projectile 2 to the front end of the central blind hole.

[0056] Step 4-2: Determine the bottom thickness of the centering part 4 according to the design requirements and geometric relationships. At this time, the bottom thickness direction bears the reaction force of the inertial force of the front centering part 1 and the projectile 2. , To meet the material shear strength requirements Less than the allowable shear stress of the material ,Right now Thus, the thickness of the bottom of the centering part 4 is obtained. ,satisfy Rounding up gives the inner ring thickness of the lightweight ring support. .

[0057] Step 4-3: Determine the thickness of the centering part 4 according to the design requirements and geometric relationships. Based on design experience, to ensure the stability of the launch process, The design scope is: .

[0058] The connection between the inner ring 8 and the outer ring 7 of the front centering part adopts an arc-shaped transition structure to avoid the generation of concentrated stress during the launch process, improve the structural strength of the front centering part 1 under strong impact load, ensure the integrity of the front centering part 1 in the launch device, and ensure the stability of the projectile 2 during the launch process.

[0059] The chamfer on the front centering part 1 can eliminate burrs generated during machining, reduce damage to the inner wall of the launching device, and also facilitate the adjustment of the front centering part 1 into the launching device, so as to achieve the purpose of rapid installation.

[0060] The bottom end of the rear centering part 4 is a stepped shaft, and the stepped shaft pressure ring 16 is connected by a thread. A gas-sealing ring 15 is provided between the two. During the screwing process, the gas-sealing ring 15 is pressed to restrict its axial displacement, thereby enabling the gas-sealing ring 15 to achieve the gas-sealing function. During the launch process, the rear centering part 4 bears the launch overload and transmits thrust to the projectile body 2 through the bottom of the inner hole 13.

[0061] During the launch process, most of the gas thrust generated by the combustion of propellant directly acts on the rear centering part 4. The rear centering part 4 converts the gas thrust into the acceleration of the projectile 2. In order to ensure that the rear centering part 4 can withstand the above load and ensure structural integrity, the bottom of the rear centering part 4 retains a sufficiently thick material. In addition, the rear centering part 4 is made of TA15 titanium alloy material to reduce the total mass while ensuring structural strength.

[0062] Among them, the pressure ring 16 is a structural component that comes into direct contact with the gas and is one of the components that converts the gas thrust into the projectile acceleration. Therefore, it is necessary to ensure that it does not break or yield during the launch process. The high-strength alloy steel 30CrMnSiA is used, which can meet the requirements well.

[0063] Among them, the gas-sealing ring 15 is installed between the rear centering part 4 and the pressure ring 6. The gas-sealing ring 5 is a ring made of nylon material. Under prestress, the gas-sealing ring is nested on the rear end face boss of the rear centering part 4. The outer diameter of the gas-sealing ring 5 is larger than the maximum outer circumference diameter of the rear centering part 4. The gas-sealing ring 5 forms an interference fit with the inner wall of the launching device. The gas-sealing ring 5 relies on the pressure of the gas in the chamber on the curved skirt to make the skirt warp outward and stick tightly to the inner wall of the launching device, ensuring the gas-sealing effect and effectively avoiding the loss caused by the direct contact between the rear centering part 4 and the inner wall of the launching device.

[0064] The above description is merely a specific embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Obviously, any person skilled in the art can make various changes or modifications within the scope of the claims, which do not affect the substantive content of the present invention and should all be covered within the scope of protection of the present invention. Therefore, the scope of protection of the present invention should be determined by the scope of the claims.

Claims

1. A lightweight split centering structure suitable for a sub-caliber dynamic acceleration device, characterized in that: Includes a front centering section (1), a rear centering section (4), an adjustment mechanism (3), an air-closing ring (5), and a pressure ring (6); The anterior core (1) is composed of It consists of a lightweight ring-shaped support with weight-reducing grooves. The projectile (2) is fitted into the center holes of each annular bracket of the front centering part (1), and the bottom end of the projectile (2) is inserted into the center of the rear centering part (4); the outer ring wall of the front centering part (1) is fitted with the inner wall of the launch cavity with a clearance fit, and the front end and rear end of the front centering part (1) are respectively provided with weight reduction grooves. The front centering part (1) achieves weight reduction by removing the three arcs on its outer ring, so that the cross-section of the outer ring is trident-shaped, and a through hole is provided on the connection part between the outer ring and the inner ring of the front centering part (1); The rear centering part (4) is a rotating body with a clearance fit between its outer wall and the inner wall of the launch cavity. The center of the front end face of the rear centering part (4) has a central blind hole for connecting the projectile (2). The outer ring of the central blind hole has a circular weight-reducing groove. Three threaded blind holes are evenly arranged on the front end face near the outer ring. The bottom end of the rear centering part (4) is a stepped shaft. The stepped shaft pressure ring (6) is connected by threads, and a sealing ring (5) is provided between the two. The adjustment mechanism (3) consists of three long screws. The front centering part (1) and the rear centering part (4) are connected through the adjustment mechanism (3). The three long screws pass through the through hole of the front centering part (1) from front to back and engage with the threaded hole of the rear centering part (4). Nuts are used to axially position the ring bracket.

2. The lightweight split-type centering structure suitable for sub-caliber dynamic acceleration devices according to claim 1, characterized in that: The central axis of the weight reduction groove of the front centering part (1) coincides with the central axis of the projectile.

3. A lightweight split-type centering structure suitable for sub-caliber dynamic acceleration devices according to claim 2, characterized in that: The rotation axes of the three through holes on the front centering part (1) are parallel to the rotation axis of the projectile.

4. A lightweight split-type centering structure suitable for sub-caliber dynamic acceleration devices according to claim 3, characterized in that: The front centering part (1) achieves weight reduction by removing three equally spaced arcs on its outer ring, and the central axis of the removed arc part is parallel to the central axis of the projectile.

5. A lightweight split-type centering structure suitable for sub-caliber dynamic acceleration devices according to claim 4, characterized in that: The front centering part (1) and the rear centering part (4) have outer peripheral chamfers on their end faces facing the launch direction.

6. A lightweight split-type centering structure suitable for sub-caliber dynamic acceleration devices according to claim 5, characterized in that: The outer diameter of the pressure ring (6) is smaller than the inner diameter of the air-sealing ring (5).

7. A lightweight split-type centering structure suitable for sub-caliber dynamic acceleration devices according to claim 6, characterized in that: The air-sealing ring (5) is an annular skirt structure with an outer diameter not less than the inner diameter of the inner wall of the emission cavity. The cross-section on one side is "L" shaped and is fitted between the pressure ring (6) and the rear centering part (4).

8. A design method for a lightweight split-type centering structure for a sub-caliber dynamic acceleration device as described in any one of claims 1 to 7, characterized in that, The steps are as follows: Step 1: Determine the initial parameters of the dynamic acceleration device before its sub-caliber launch test, including: the inner diameter of the launch cavity wall. Lightweight ring support outer diameter The inner diameter d of the lightweight ring-shaped support; the number of lightweight ring-shaped supports. The cross-sectional area of ​​the inner wall of the launch cavity was further determined by the lightweight annular support spacing L, launch overload a, and missile base thrust F. The mass of the projectile (2) The length of the projectile (2) The diameter of the projectile (2) Proceed to step 2; Step 2: Determine the total launch mass Based on the given mass of the projectile (2) Determine the quality of the pre-centering part (1) and the quality of the centering part (4) , Proceed to step 3; Step 3: Determine the structural parameters of the front centering part (1) and the adjustment mechanism (3), including: the diameter of the through hole of the front centering part (1). Lightweight ring support outer ring thickness The thickness of the connecting part of the lightweight ring bracket Inner ring thickness of lightweight ring support Screw module m, proceed to step 4; Step 4: Determine the structural parameters of the rear centering part (4), including: the depth of the threaded blind hole in the rear centering part (4). The thickness of the bottom of the centering part (4) Thickness of the centering part (4) .

9. The design method of the lightweight split-type centering structure of the sub-caliber dynamic acceleration device according to claim 8, characterized in that, In step 3, the structural parameters of the front centering part (1) and the adjustment mechanism (3) are determined, including: the diameter of the through hole of the front centering part (1). Lightweight ring support outer ring thickness The thickness of the connecting part of the lightweight ring bracket Inner ring thickness of lightweight ring support The screw module m is as follows: Step 3-1: According to the design requirements, as well as the launch overload a and the mass of the front centering part (1), The inertial force at this time is calculated, which is the working load borne by the screw. , ; Step 3-2: Based on design requirements and working load Determine the total load : To ensure the safety and reliability of the threaded connection, residual preload is used. Then the preload At this time, the total load , ,in For screw stiffness, The stiffness of the anterior core (1) is given; for a conservative estimate, Simplified to ; Step 3-3: Determine the screw module m based on design requirements and total load: Tensile stress of the screw It should be less than the allowable stress of the material. , Let be the stress cross-sectional area of ​​the screw, i.e.: Therefore, the screw module m satisfies The diameter of the through hole in the front centering part (1) is obtained by rounding up the modulus m. ; Steps 3-4: Based on design requirements and total load Determine the inner ring thickness of the lightweight ring support. The shear strength of the inner ring material of the lightweight ring support It should be less than the allowable shear stress of the material. ,Right now Thus, the inner ring thickness of the lightweight annular support is obtained. satisfy Round up to obtain the inner ring thickness of the lightweight ring support. ; Steps 3-5: Calculate the outer ring thickness of the lightweight ring support based on design requirements and geometric relationships. And the thickness of the connecting part of the lightweight ring support. , ; Steps 3-6: Pass the screw through the through hole of the front centering part (1), and use nuts to position and tighten it on the front and rear end faces of the lightweight ring bracket.

10. The design method of the lightweight split-type centering structure of the sub-caliber dynamic acceleration device according to claim 9, characterized in that, In step 4, the structural parameters of the rear centering part (4) are determined, including: the depth of the central blind hole of the rear centering part (4). The thickness of the bottom of the centering part (4) Thickness of the centering part (4) The details are as follows: Step 4-1: Determine the depth of the threaded blind hole in the centering part (4) according to the design requirements and geometric relationships. : First, according to the inner diameter of the launch cavity specified in the design requirements... Based on the outer diameter D of the lightweight annular support, determine the allowable droop distance of the free end of the projectile (2). ,in The working condition of the projectile (2) being inserted into the blind hole in the center of the rear centering part (4) is simplified to a cantilever beam model with one end fixed and the other end free; at this time For the maximum allowable deflection, The formula for calculating maximum deflection can be modified to obtain... ,at this time Where E is the elastic modulus of the projectile material, I is the moment of inertia of the projectile cross section, and P is the equivalent load at the free end. The distance from the top of the projectile (2) to the front end face of the central blind hole; Step 4-2: Based on the design requirements and geometric relationships, determine the bottom thickness of the centering part (4). At this time, the bottom part in the thickness direction bears the reaction force of the inertial force of the front centering part (1) and the projectile (2). , To meet the material shear strength requirements Less than the allowable shear stress of the material ,Right now Thus, the bottom thickness of the centering part (4) is obtained. ,satisfy Rounding up gives the inner ring thickness of the lightweight ring support. ; Step 4-3: Determine the thickness of the centering part (4) according to the design requirements and geometric relationships. Based on design experience, to ensure the stability of the launch process, The design scope is: .

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