A two-stage pneumatic shell-removing device with parallel shaft eccentric arrangement

Abstract

This invention belongs to the field of impact dynamics, specifically relating to a two-stage pneumatic sabotage device with an eccentrically arranged parallel axis. It includes a connecting section that connects to the gun barrel, and this connecting section is connected to one end of the sabot recovery chamber body via a sealing device. The sabotage recovery chamber body houses a sabotage mechanism. The sabotage mechanism includes a primary sabotage baffle and a secondary sabotage baffle arranged along the ballistic axis. The circular hole in the center of the primary sabotage baffle is eccentrically positioned, so that after the shock wave is reflected from the inner wall of the primary sabotage baffle, it only exerts force and torque on the sabot, while the projectile is not subjected to force or torque, thus maintaining the projectile's attitude while causing the sabot to deviate. After sabotage removal via the eccentrically arranged secondary baffle sabotage device of this invention, complete sabotage removal is achieved, with no residual sabotage impacting the target. The sabotage device of this invention has minimal impact on the projectile's flight attitude and does not affect the test results.

Description

Technical Field

[0001] This invention belongs to the field of impact dynamics, and specifically relates to a two-stage pneumatic shell removal device with parallel shaft eccentric arrangement. Background Technology

[0002] The two-stage light gas gun is a versatile launching device, applicable to a wide range of projectile materials, shapes, and masses, and is widely used in high-speed and hypersonic experimental research. When firing metal projectiles, a plastic sabot is required to protect the bore of the gas gun barrel. The sabot's outer diameter is approximately the same as the barrel's inner diameter, and it carries the projectile at high speed towards the target. In high-speed / hypersonic collision tests with the light gas gun, the sabot can affect the cratering effect on the target and the particle velocity test results. To avoid interference from the sabot itself, a method must be found to separate the projectile from the sabot.

[0003] Currently, commonly used discarding methods are mainly divided into pneumatic discarding and mechanical discarding. Mechanical discarding separates the sabot from the projectile through direct mechanical action between an external discarding device and the sabot. However, this method inevitably results in a small number of sabots hitting the target, affecting the experimental results. Pneumatic discarding uses a flap-type sabot, consisting of multiple flaps and a base. There are typically 3-4 flaps. Figure 1 As shown. During high-speed flight, the sabot will separate from the projectile under the combined action of the shock wave at the launch tube exit and the surrounding flow field, allowing only the projectile to pass through the discarding sabot. However, existing aerodynamic discarding methods often result in the sabot also passing through the sabot and hitting the target, which seriously affects the test results. Summary of the Invention

[0004] To address the shortcomings of current discarding devices in completely removing sabots, especially the problem of the sabot hitting the target in pneumatic discarding methods, this invention provides a two-stage pneumatic discarding device with a non-concentric baffle. The impact baffle structure of this invention is simple, easy to manufacture, and convenient to disassemble, and can adapt to projectiles of various diameters. Through the non-concentric arrangement, the sabot is deflected while maintaining the projectile's attitude. After the two-stage discarding process, complete sabot removal is achieved, with no residual sabot hitting the target. The discarding device has minimal impact on the projectile's flight attitude and does not affect the test results.

[0005] The technical solution to achieve the purpose of this invention is: a two-stage pneumatic sabot removal device with parallel axis eccentric arrangement, including a connecting section connected to the gun barrel, the connecting section being connected to one end of the sabot recovery chamber body through a sealing device, and a sabot removal mechanism being provided inside the sabot recovery chamber body;

[0006] The discarding mechanism includes a primary discarding baffle and a secondary discarding baffle arranged along the trajectory axis. The circular hole in the middle of the primary discarding baffle is eccentrically arranged so that after the shock wave is reflected on the inner wall surface of the primary discarding baffle, it only exerts force and torque on the base, while the projectile is not subjected to force and torque, thus achieving the projectile attitude unchanged and the base deviating.

[0007] Furthermore, the connecting section end is provided with a flange, and multiple threaded holes are evenly distributed around the flange; multiple threaded holes are evenly distributed around the outer circumference of the sealing device; the connecting end of the sabot recovery chamber body and the sealing device is provided with a flange, and multiple threaded holes are evenly distributed around the flange; the flange of the connecting section, the sealing device and the flange of the sabot recovery chamber body are connected by bolts.

[0008] Furthermore, the sealing device has a diaphragm in the middle, and the diaphragm has a circular hole in the middle with a diameter larger than the outer diameter of the sabot, allowing the bullet to pass through.

[0009] Furthermore, the connecting section, sealing device, sabot recovery chamber body, and ejection mechanism are coaxially assembled.

[0010] Furthermore, the main body of the sabot recovery capsule is cylindrical, and the side walls are equipped with windows for measuring the missile's flight speed and observing its flight attitude.

[0011] Furthermore, the shelling mechanism also includes a hollowed-out cylindrical body and a shelling mechanism retainer;

[0012] The cylindrical body has a detachable primary ejection baffle and a secondary ejection baffle at both ends, which can be replaced according to the different projectiles.

[0013] Furthermore, the shell removal mechanism retainer consists of ribs at the front and rear outer ends of the cylindrical body, with the other end of the ribs fixedly connected to the inner wall of the sabot recovery chamber. The outer periphery of the primary shell removal baffle of the cylindrical body is provided with a fragment protection ring.

[0014] Furthermore, the eccentric setting of the circular hole in the middle of the first-stage shell-removing baffle is determined based on experiments or simulations.

[0015] Furthermore, when setting the position and shape of the circular hole of the first-stage discarding sabot according to the simulation, specifically: based on the projectile's flight speed and the numerical calculation results of the shock wave flow field by Fluent, the thickness of the first-stage discarding sabot, the offset distance between the circular hole axis and the trajectory axis, and the diameter of the circular hole are designed so that after the shock wave is reflected by the hole wall, it only exerts force and torque on the base, while the projectile is not subjected to force and torque, thereby ensuring that the projectile's attitude remains unchanged, and only the base deviates.

[0016] A method for shell removal based on the above-mentioned two-stage pneumatic shell removal device is as follows:

[0017] After passing through the diaphragm, the projectile with the sabot enters the main body of the sabot recovery chamber. The sabot's flaps separate from the projectile under the combined action of the shock wave at the gun barrel exit and the surrounding flow field.

[0018] The projectile with the base enters the round hole of the first-stage discarding baffle. The projectile with the base and the first-stage discarding baffle generate a shock wave. After the shock wave is reflected by the hole wall, it only exerts force and torque on the base, while the projectile is not subjected to force and torque, thus ensuring that the projectile's attitude remains unchanged, and only the base deviates.

[0019] As the sabot deviates from its axis, it is recovered by the secondary discarding sabot. The projectile continues to fly along the trajectory axis, passing through the secondary discarding sabot and leaving the discarding device. At the same time, the fragments generated by the clip and the primary discarding sabot are also recovered by the secondary discarding sabot, thus achieving complete discarding of the combined sabot.

[0020] Compared with the prior art, the significant advantages of this invention are:

[0021] 1. It can adapt to projectiles of various diameters simply by replacing the discarding baffle, and the removal and replacement of the discarding baffle is very convenient.

[0022] 2. After the sabot is removed by the non-concentric two-stage baffle sabot of the present invention, the sabot can be completely removed without any residual sabot hitting the target.

[0023] 3. The discarding device involved in this invention has minimal impact on the flight attitude of the projectile and does not affect the test results. Attached Figure Description

[0024] Figure 1 This is a picture of a card-type discarding sabot.

[0025] Figure 2 This is a design calculation diagram of the first-stage shell-removing baffle of the present invention.

[0026] Figure 3 This is a three-dimensional diagram of the shell-removing device of the present invention.

[0027] Figure 4 This is a cross-sectional view of the shelling device of the present invention.

[0028] Figure 5 A partial view of the primary shelling baffle of the shelling device.

[0029] Explanation of reference numerals in the attached figures:

[0030] 1-Cannon barrel, 2-Connecting section, 3-Sealing device, 4-Diaphragm, 5-Main body of sabot recovery chamber, 6-Projectile attitude observation window, 7-Removing sabot mechanism retainer, 8-First-stage removing sabot baffle, 9-Second-stage removing sabot baffle, 10-Fragment protection ring, 11-Removing sabot mechanism, 12-End flange. Detailed Implementation

[0031] The present invention will now be described in further detail with reference to the accompanying drawings.

[0032] like Figure 1-5 As shown, a pneumatic sabot removal device with a non-concentric arrangement of two-stage baffles includes: a connecting section 2 coaxially arranged on the outside of the exit end of the gun barrel 1 and a sealing device 3, wherein the center of the sealing device 3 is a diaphragm 4, and the diameter of the diaphragm 4 is larger than the outer diameter of the sabot.

[0033] The connecting section 2, sealing device 3, and sabot recovery chamber body 5 are connected by bolts. The sabot removal mechanism retainer 7 of the sabot removal mechanism 11 is connected to the sabot recovery chamber body 5 by welding. The connecting section 2, sealing device 3, sabot recovery chamber body 5, and sabot removal mechanism 11 are coaxially assembled. The sabot recovery chamber body 5 is cylindrical, with missile flight speed measurement windows and missile flight attitude observation windows arranged on it.

[0034] The primary ejection baffle 8 and the secondary ejection baffle 9 are bolted to the front and rear sides of the ejection mechanism 11, respectively, for easy disassembly and replacement. The primary ejection baffle 8 has an eccentrically arranged circular hole to recover the ejector clip and induce the base to deflect while ensuring the passage of the projectile. The secondary ejection baffle 9 has a circular hole in the center for the recovery of clip fragments and the base.

[0035] The diameter of the diaphragm 4 is larger than the outer diameter of the sabot, so that both the projectile and the sabot can smoothly enter the main body 5 of the sabot recovery chamber. Since there is a certain pressure of air (atmospheric pressure) inside the recovery chamber, the high-speed moving flap will be separated from the projectile under the combined action of the shock wave at the exit of the launch tube, i.e. the gun barrel 1 and the surrounding flow field. Thus, only the projectile and the sabot can smoothly enter the round hole of the first-stage discarding sabot 8. The flap in the sabot will collide with the first-stage discarding sabot 8 and be intercepted.

[0036] When the base and the projectile enter the circular hole of the first-stage discarding sabot 8 together, the projectile and the base will generate a shock wave with the first-stage discarding sabot 8. Based on the projectile's flight velocity and length required for the experiment, numerical calculations of the shock wave flow field are performed using the Fluent flow field analysis software. This yields the spatial distribution of the shock wave system. The thickness of the baffle, the offset distance between the circular hole axis and the projectile axis, and the diameter of the circular hole are designed to ensure that after the shock wave reflects off the hole wall, it only exerts force and torque on the base, while the projectile is not subjected to force or torque. This ensures that the projectile's attitude remains unchanged, and only the base deviates (e.g., ...). Figure 2 (As shown); After the projectile and the base pass through the first-stage discarding sabot 8, the projectile continues to fly along the trajectory axis and leaves the discarding device. The base is recovered by the second-stage discarding sabot 9 due to its attitude deviating from the axis. At the same time, the fragments generated by the card flap and the first-stage discarding sabot 8 are also recovered by the second-stage discarding sabot 9 in this stage, thus achieving complete discarding of the combined sabot.

[0037] The main body of the shell-removing mechanism is a hollow thin-walled cylinder.

[0038] The main body 5 of the sabot recovery chamber and the components connected to it by bolts are arranged in a ring with N screw holes around the central axis, which facilitates the disassembly and replacement of each connection part.

[0039] The cylindrical body of the ejection mechanism is bolted to the ejection baffle, and both have N bolt holes arranged in a ring around the central axis. This facilitates the replacement of the ejection section when it is damaged or when a different model is needed to replace the projectile, thus reducing operating costs.

[0040] The shell-removal baffle is a consumable material, and inexpensive materials such as No. 20 steel or No. 45 steel can be used to reduce experimental costs.

[0041] The main body of the sabot recovery capsule is equipped with observation windows for flight speed and attitude, as well as fiber optic channels for particle flight speed, to facilitate various subsequent measurements.

[0042] This device can be applied to fields such as materials science, impact dynamics, weapon science, and protective engineering.

Claims

1. A method for shell removal using a two-stage pneumatic shell removal device based on a parallel-axis eccentric arrangement, characterized in that, The parallel-axis eccentrically arranged two-stage pneumatic discarding device includes a connecting section (2) connected to the gun barrel (1). The connecting section (2) is connected to one end of the sabot recovery chamber body (5) through a sealing device (3). The sabot recovery chamber body (5) is equipped with a discarding mechanism (11). The discarding mechanism (11) includes a first-stage discarding baffle (8) and a second-stage discarding baffle (9) arranged along the trajectory axis. The circular hole in the middle of the first-stage discarding baffle (8) is eccentrically arranged so that the shock wave is reflected on the inner wall surface of the first-stage discarding baffle and only exerts force and torque on the bottom support. The projectile is not subjected to force and torque, so that the projectile attitude remains unchanged and the bottom support deviates. The sealing device (3) is provided with a diaphragm (4) in the middle. The diaphragm (4) is provided with a circular hole in the middle with a diameter larger than the outer diameter of the sabot for the bullet to pass through. The specific method is as follows: After passing through the diaphragm, the projectile with the sabot enters the main body of the sabot recovery chamber. The sabot's flaps separate from the projectile under the combined action of the shock wave at the gun barrel exit and the surrounding flow field. The projectile with the base enters the round hole of the first-stage discarding baffle. The projectile with the base and the first-stage discarding baffle generate a shock wave. After the shock wave is reflected by the hole wall, it only exerts force and torque on the base, while the projectile is not subjected to force and torque, thus ensuring that the projectile's attitude remains unchanged, and only the base deviates. As the sabot deviates from its axis, it is recovered by the secondary discarding sabot. The projectile continues to fly along the trajectory axis, passing through the secondary discarding sabot and leaving the discarding device. At the same time, the fragments generated by the clip and the primary discarding sabot are also recovered by the secondary discarding sabot, thus achieving complete discarding of the combined sabot.

2. The method according to claim 1, characterized in that, The end of the connecting section (2) is provided with a flange, and multiple threaded holes are evenly distributed around the flange. The outer circumference of the sealing device (3) is evenly distributed with multiple threaded holes. The connecting end of the main body (5) of the missile recovery chamber and the sealing device (3) is provided with a flange, and multiple threaded holes are evenly distributed around the flange. The flange of the connecting section, the sealing device and the flange of the main body (5) of the missile recovery chamber are connected by bolts.

3. The method according to claim 1, characterized in that, The connecting section (2), sealing device (3), sabot recovery chamber body (5) and shell removal mechanism (11) are coaxially assembled.

4. The method according to claim 1, characterized in that, The main body (5) of the sabot recovery chamber is cylindrical in shape, and the side wall is provided with a missile flight speed measurement window and a missile flight attitude observation window.

5. The method according to claim 1, characterized in that, The shelling mechanism (11) also includes a hollow cylindrical body and a shelling mechanism retainer (7); The cylindrical body has a primary ejection baffle (8) and a secondary ejection baffle (9) detachably connected at both ends. The primary ejection baffle (8) and the secondary ejection baffle (9) can be replaced according to the different projectiles.

6. The method according to claim 5, characterized in that, The shell removal mechanism retainer (7) is a rib plate set at the front and rear outer ends of the cylindrical body. The other end of the rib plate is fixedly connected to the inner wall of the sabot recovery chamber body (5). The outer periphery of the first-stage shell removal baffle of the cylindrical body is provided with a fragment protection ring (10).

7. The method according to claim 1, characterized in that, The eccentric setting of the circular hole in the middle of the first-stage shell-removing baffle (8) is determined by experiment or simulation.

8. The method according to claim 7, characterized in that, When setting the position and shape of the circular hole of the first-stage discarding sabot according to the simulation, specifically: based on the projectile's flight speed and the numerical calculation results of the shock wave flow field using the Fluent software, the thickness of the first-stage discarding sabot, the offset distance between the circular hole axis and the trajectory axis, and the diameter of the circular hole are designed so that after the shock wave is reflected by the hole wall, it only exerts force and torque on the base, while the projectile is not subjected to force and torque, thus ensuring that the projectile's attitude remains unchanged, and only the base deviates.

Images