Projectile with adjustable length

Abstract

The application belongs to the field of ammunition development, and particularly relates to a variable-structure shell with adjustable length of projectile, which specifically comprises a body, a bullet head, a bullet tail, a length adjusting assembly, a limiting unlocking assembly and a belt; the bullet head and the bullet tail are arranged in the body and can slide along the axial direction relative to the body; the length adjusting assembly is arranged between the bullet head and the bullet tail and is used for adjusting the length of the bullet head, the length of the bullet tail and the total length of the projectile; the belt is sleeved on the rear position of the outer surface of the body, and the limiting unlocking assembly is arranged between the bullet head and the bullet tail and is used for unlocking and limiting the belt. Compared with the prior art, the application can remove the belt after the projectile is fired, and adjust the length of the bullet head, the length of the bullet tail and the total length of the projectile during the flight according to the speed of the projectile, so that the air resistance is effectively reduced and the firing range of the artillery is improved.

Description

Technical Field

[0001] This invention belongs to the field of ammunition development, specifically relating to a projectile with an adjustable length and variable structure. Background Technology

[0002] Most artillery shells currently used are of a fixed structure. Taking the most common high-explosive shell as an example, it has a conical warhead, a cylindrical body in the middle and rear, and a boat-shaped tail. A projectile belt is fixed to the rear of the projectile body. During firing, the propellant gases inside the barrel propel the projectile forward. The projectile belt and the rifling of the barrel work together to make the projectile spin at high speed while moving forward, ensuring flight stability.

[0003] In external ballistics, we know that air resistance includes three types: frictional drag, eddy current drag, and shock wave drag. Frictional drag is generated by the friction between the projectile surface and the air. To reduce frictional drag, the projectile surface must be made smooth. Eddy current drag is caused by the pressure difference created when the air pressure in front of the projectile is higher than that behind it. The air around the low-pressure area flows in to replenish it, creating vortices at the bottom of the projectile, hence the name eddy current drag. To reduce eddy current drag, the tail of the projectile should be streamlined or boat-tail shaped, or a bottom concave or bottom-displacement technique should be used. Shock wave drag is caused by the high-speed motion of the projectile. The air disturbances in front of the projectile do not have time to propagate and overlap, forming a dense air layer in front of the projectile. The increased pressure and temperature of the air layer cause energy consumption. To reduce shock wave drag, the projectile nose should be made very sharp, such as with the "date pit" projectile technique. Considering that the composition of air resistance varies at different projectile velocities, such as a higher proportion of frictional resistance at low speeds and a higher proportion of shock wave resistance at high speeds, we can derive the projectile shape rule that minimizes air resistance: as the projectile velocity increases, the total length of the projectile and the length of the projectile head should gradually increase, while the length of the projectile tail should gradually decrease.

[0004] Looking at current artillery shells, they are typically fired at a certain angle. During flight, the projectile's velocity gradually decreases (ascent phase) and then gradually increases (descend phase). Because the projectile has a fixed structure, air resistance cannot be reduced by adjusting its shape. Furthermore, after leaving the barrel, the grooved cartridge band remains on the projectile body, increasing frictional resistance. Considering the recent advancements in guided projectile technology, adjusting the projectile's structure during flight has become possible. Therefore, a projectile design with an adjustable length and variable structure is proposed. Summary of the Invention

[0005] The purpose of this invention is to provide a projectile with an adjustable length and variable structure, which allows the projectile to remove the cartridge case after leaving the barrel and adjust the length of each part of the projectile according to the projectile speed during flight, thereby effectively reducing air resistance and increasing the range of the artillery.

[0006] The technical solution to achieve the purpose of this invention is as follows: a projectile with adjustable length and variable structure, comprising a body, a projectile head, a projectile tail, a length adjustment component, a limiting and unlocking component, and a projectile belt; the projectile head and the projectile tail are disposed within the body, and the projectile head and the projectile tail can slide relative to the body in the axial direction; the length adjustment component is disposed between the projectile head and the projectile tail, and is used to adjust the length of the projectile head, the length of the projectile tail, and the total length of the projectile; the projectile belt is sleeved on the outer surface of the body at a rear position, and the limiting and unlocking component is disposed between the projectile head and the projectile tail, and is used to unlock and limit the projectile belt.

[0007] Furthermore, the body is provided with a projectile anti-rotation groove and a projectile tail anti-rotation groove. The anti-rotation groove is used to limit the rotation of the projectile head and the projectile tail relative to the body. A gap is provided between the outer surface of the projectile band and the body. Four through holes are opened on the body cylinder wall opposite to the center position of the projectile band for the top rod in the positioning assembly to pass through.

[0008] Furthermore, the projectile includes a cylindrical section and an elliptical conical section, with a threaded hole for the projectile at the central axis of the bottom surface of the cylindrical section; a projectile anti-rotation pin is provided on the side wall of the cylindrical section of the projectile, which cooperates with the projectile anti-rotation groove.

[0009] Furthermore, the projectile tail includes a cylindrical section and a frustum end, with a threaded hole for the projectile tail at the central axis of the bottom surface of the cylindrical section; a projectile tail anti-rotation pin is provided on the side wall of the cylindrical section of the projectile tail, which cooperates with the projectile tail anti-rotation groove.

[0010] The further limit and unlocking components include a control compartment, a push rod compartment, a cylindrical connecting rod, a push rod, a push rod spring, a cam, and a cam motor. A fan-shaped fixing plate is set in the control compartment, with the push rod compartment fixedly connected at its inner central axis and the main body fixedly connected on its outer side. One end of the cylindrical connecting rod is fixedly installed at the through hole position on the main body, and the other end is fixedly connected to the cylindrical wall of the push rod compartment. A push rod spring is sleeved on the push rod and installed inside the cylindrical connecting rod. The cam motor is fixedly installed in the push rod compartment, and the cam motor shaft of the cam motor is fixedly connected to the cam, so that the rotation of the cam motor shaft drives the cam to rotate.

[0011] Furthermore, a connecting rod baffle is provided at the end of the cylindrical connecting rod near the spring belt; the side wall of the top rod compartment has a hole, and the position of the corresponding hole is connected to the cylindrical connecting rod.

[0012] Furthermore, the push rod includes a push rod body, a push rod head, a push rod protrusion, and a push rod tail end; the push rod head mates with a circular spring band groove for spring band limiting; the push rod protrusion connects one end of the push rod spring, the other end of the push rod spring connects to the connecting rod baffle, and the push rod tail end contacts the outer contour line of the cam.

[0013] Furthermore, the length adjustment assembly includes two sets of motor assemblies: a projectile motor and a projectile tail motor. The projectile motor is fixedly mounted on the cylindrical end face at the front end of the top rod compartment. The projectile motor has a projectile motor shaft, which is connected to a projectile screw. The projectile screw engages with a projectile threaded hole on the projectile. Rotation of the projectile motor shaft drives the projectile screw to rotate, thereby causing the projectile to move along the axial direction of the body. The projectile tail motor is fixedly mounted on the cylindrical end face at the other end of the top rod compartment. The projectile tail motor has a projectile tail motor shaft, which is connected to a projectile tail screw. The projectile tail screw engages with a projectile tail threaded hole on the projectile tail. Rotation of the projectile tail motor shaft drives the projectile tail screw to rotate, thereby causing the projectile tail to move along the axial direction of the body.

[0014] Furthermore, a speed sensor, a controller, and a power supply are also installed on the fixed plate of the control cabin. The speed sensor is used to collect the speed signal of the projectile; the controller is used to control the timing and duration of the motor unit's drive.

[0015] Furthermore, the cam has a four-part structure, including four convex parts and four concave parts.

[0016] The significant advantages of this invention compared to existing technologies are:

[0017] (1) By adjusting the length of the projectile head, the length of the projectile tail and the total length of the projectile, air resistance can be effectively reduced and the range of the artillery can be increased.

[0018] (2) By designing the limit unlocking component, the limit and unlocking of the spring belt can be realized, which can also reduce air resistance. Attached Figure Description

[0019] Figure 1 A schematic diagram of the cross-section of a rotating body of a variable-structure projectile;

[0020] Figure 2 This is a cross-sectional view of the warhead.

[0021] Figure 3 This is a cross-sectional view of the missile tail.

[0022] Figure 4 This is a cross-sectional view of a variable-structure projectile.

[0023] Figure 5 This is a schematic diagram showing the positions of the cam and pushrod structure;

[0024] Figure 6 This is a cross-sectional view of the rotating belt.

[0025] 1—Body; 1.1—Projectile anti-rotation groove; 1.2—Projectile tail anti-rotation groove; 2—Projectile; 2.1—Projectile threaded hole; 2.2—Projectile anti-rotation pin; 3—Projectile tail; 3.1—Projectile tail threaded hole; 3.2—Projectile tail anti-rotation pin; 4—Projectile band; 4.1—Projectile band groove; 5—Control compartment; 5.1—Fixing plate; 6—Top rod compartment; 7—Cylindrical connecting rod; 7.1—Connecting rod baffle; 8—Top rod; 8.1—Top rod head; 8.2—Top rod protrusion; 8.3—Top rod tail end; 9—Top rod spring; 10—Cam; 11—Power supply; 12—Cable; 13—Speed ​​sensor; 14—Controller; 15—Motor assembly; 15.1—Cam motor; 15.2—Cam motor shaft; 15.3—Projectile motor; 15.4—Projectile motor shaft; 15.5—Projectile tail motor; 15.6—Projectile tail motor shaft. Detailed Implementation

[0026] The present invention will be further described below with reference to the accompanying drawings and specific embodiments. The present invention discloses a projectile with adjustable projectile length and variable structure, the projectile including a body 1, a projectile head 2, a projectile tail 3, a length adjustment component, a limit unlocking component, and a projectile belt 4.

[0027] The main body 1 is a thin-walled cylindrical structure with a projectile anti-rotation groove 1.1 and a projectile tail anti-rotation groove 1.2 inside. The anti-rotation grooves are used to limit the rotation of the projectile 2 and the projectile tail 3 relative to the main body 1. Four through holes are opened on the cylindrical wall for the top rod 8 in the positioning assembly to pass through.

[0028] The projectile 2 is a rotating structure, consisting of a cylindrical section and an elliptical conical section. The cylindrical section can slide along the axial direction within the body 1. A projectile threaded hole 2.1 is opened at the center axis of the bottom surface of the cylindrical section. A projectile anti-rotation pin 2.2 is provided on the side wall of the cylindrical section of the projectile 2, which cooperates with the projectile anti-rotation groove 1.1.

[0029] The tail 3 is a rotating structure, including a cylindrical section and a frustum end. The cylindrical section can slide along the axial direction within the body 1. A threaded hole 3.1 for the tail is opened at the center axis of the bottom surface of the cylindrical section. A tail anti-rotation pin 3.2 is provided on the side wall of the cylindrical section of the tail 3, which cooperates with the tail anti-rotation groove 1.2.

[0030] Furthermore, the body 1 has a smooth transition with the warhead and tail to reduce air resistance.

[0031] The spring belt 4 is a cylindrical structure, installed on the outer wall of the body 1, and has a clearance fit with the body 1; the inner side of the spring belt 4 has 4 round spring belt grooves 4.1 for cooperating with the push rod 8.

[0032] The limit unlocking assembly includes a control compartment 5, a push rod compartment 6, a cylindrical connecting rod 7, a push rod 8, a push rod spring 9, a cam 10, and a cam motor 15.1. The control compartment 5 is equipped with four fan-shaped fixing plates 5.1, which are fixedly connected to the push rod compartment 6 at the inner central axis and fixedly connected to the body 1 on the outer side. One end of the cylindrical connecting rod 7 is fixedly installed at the through hole position on the body 1, and the other end is fixedly connected to the cylindrical wall of the push rod compartment 6. The cam motor 15.1 is fixedly installed inside the push rod compartment 6, and the cam motor shaft 15.2 of the cam motor 15.1 is fixedly connected to the cam 10, so that the rotation of the cam motor shaft 15.2 drives the cam 10 to rotate.

[0033] The cylindrical connecting rod 7 has a hollow structure, and a connecting rod baffle 7.1 is provided at one end near the spring band 4; the side wall of the push rod compartment 6 has a hole, and the position of the corresponding hole is connected to the cylindrical connecting rod 7; the push rod spring 9 is sleeved on the push rod 8 and installed in the cylindrical connecting rod 7, and cooperates with the outer contour line of the cam to realize that the push rod 8 moves in the cylindrical connecting rod 7 and along the length direction of the cylindrical connecting rod 7, thereby realizing locking and unlocking with the spring band 4.

[0034] The cylindrical connecting rod 7 is provided in four sets; consequently, the push rod 8 and the push rod spring 9 are provided in four sets.

[0035] The push rod 8 includes a push rod body, a push rod head 8.1, a push rod protrusion 8.2, and a push rod tail end 8.3; the push rod head 8.1 cooperates with the round hole-shaped spring band groove 4.1 for spring band limiting; the push rod protrusion 8.2 is used to connect one end of the push rod spring 9, the other end of the push rod spring 9 is connected to the connecting rod baffle 7.1, and the push rod tail end 8.3 contacts the outer contour line of the cam; thereby driving the entire push rod 8 to move within the cylindrical connecting rod 7.

[0036] The cam 10 has a four-part structure, including four protrusions and four concave parts. The outer contour of the cam 10 contacts the tail end 8.3 of the push rod. When the protrusion contacts the tail end 8.3 of the push rod, the push rod 8 moves outward in the radial direction, compressing the push rod spring 9. The head 8.1 of the push rod then engages in the circular spring band groove 4.1, locking the spring band 4 and restricting its axial and circumferential movement along the body 1. At this time, a gap is formed between the spring band 4 and the outer wall of the body 1. When the concave part contacts the tail end 8.3 of the push rod, the pressure on the push rod spring 9 is released. Due to the action of the spring 9, the push rod 8 moves inward in the radial direction, and the head 8.1 of the push rod disengages from the annular spring band groove 4.1, thus unlocking the spring band.

[0037] The top rod compartment 6 is a cylindrical hollow structure.

[0038] The length adjustment assembly includes two sets of motor assemblies: a projectile motor 15.3 and a projectile tail motor 15.5. The projectile motor 15.3 is fixedly mounted on the cylindrical end face of the front end of the top rod compartment 6. The projectile motor 15.3 has a projectile motor shaft 15.4, which is connected to a projectile screw. The projectile screw engages with the projectile threaded hole 2.1 on the projectile 2. Rotation of the projectile motor shaft 15.4 causes the projectile screw to rotate, thereby causing the projectile to move along the axial direction of the body 1. The projectile tail motor 15.5 is fixedly mounted on the cylindrical end face of the other end of the top rod compartment 6. The projectile tail motor 15.5 has a projectile tail motor shaft 15.6, which is connected to a projectile tail screw. The projectile tail screw engages with the projectile tail threaded hole 3.1 on the projectile tail 3. Rotation of the projectile tail motor shaft 15.6 causes the projectile tail screw to rotate, thereby causing the projectile tail to move along the axial direction of the body 1.

[0039] Furthermore, the cam motor 15.1, the bullet head motor 15.3, and the bullet tail motor 15.5 are servo motors;

[0040] A speed sensor 13, a controller 14, and a power supply 11 are also installed on the mounting plate 5.1 of the control compartment 5. The speed sensor 13 is used to collect the speed signal of the projectile; the controller 14 is used to control the driving timing and duration of the motor assembly. The speed sensor 13, controller 14, and power supply 11 are fixed on the mounting plate 5.1, and their installation positions are reasonably arranged to ensure that the center of mass of the projectile is near the central axis of the body 1. The speed sensor, controller, power supply, and motor are connected by a cable 12.

[0041] The working process of the adjustable-length variable-structure projectile of the present invention is as follows:

[0042] Before the shell is fired, the convex part of the cam 10 contacts the tail end 8.3 of the push rod, and the push rod head 8.1 is locked in the cartridge belt groove 4.1, which restricts the axial movement and circumferential rotation of the cartridge belt 4 relative to the body, and maintains a slight gap between the cartridge belt 4 and the body 1.

[0043] During the process of the projectile being squeezed into the rifling, the projectile belt 4 is squeezed by the rifling and grooves are cut on the surface of the projectile belt. The projectile belt 4 is squeezed and deformed, and the inner surface is tightly attached to the surface of the body. After the projectile leaves the barrel, the squeezing effect of the rifling disappears, the elastic deformation of the projectile belt 4 is restored, and the gap between the inner surface of the projectile belt 4 and the outer surface of the body 1 reappears, preparing for the release of the projectile belt 4.

[0044] After the projectile leaves the barrel, the controller 14 calculates the projectile's exit distance based on the signal from the velocity sensor 13. When the projectile has exited the barrel at a distance of tens of meters, the controller 14 drives the cam motor to rotate 45°. At this time, the tail end 8.3 of the push rod disengages from the convex part of the cam 4. Under the restoring force of the push rod spring 9, the push rod 8 moves towards the projectile axis. The tail end 8.3 of the push rod abuts against the concave part of the cam 4, and the head 8.1 of the push rod disengages from the cartridge band groove 4.1, releasing the restriction on the cartridge band 4.1. The cartridge band 4.1 slides backward from the projectile body under the action of air resistance.

[0045] Subsequently, the controller 14 drives the projectile motor 15.3 and the tail motor 15.5 in a timely manner according to the signal from the speed sensor 13, so that the projectile 2 and the tail 3 move along the axis of the body 1. According to the principle that "as the projectile speed increases, the length of the projectile head and the total length of the projectile become longer, and the length of the projectile tail becomes shorter", the length of each part of the projectile is adjusted to ensure that the air resistance of the projectile is small, so as to achieve the purpose of increasing the range of the projectile.

Claims

1. A projectile with adjustable length and variable structure, characterized in that, It includes a body, a projectile, a tail, a length adjustment component, a limit and unlock component, and a projectile belt; the projectile and tail are located inside the body and can slide relative to the body in the axial direction; the length adjustment component is located between the projectile and tail and is used to adjust the length of the projectile head, the length of the projectile tail, and the total length of the projectile; the projectile belt is sleeved on the outer surface of the body at a rear position, and the limit and unlock component is located between the projectile and tail and is used to unlock and limit the projectile belt; The limit unlocking assembly includes a control compartment, a push rod compartment, a cylindrical connecting rod, a push rod, a push rod spring, a cam, and a cam motor. A fan-shaped fixing plate is installed in the control compartment, with the push rod compartment fixedly connected to its inner central axis and the main body fixedly connected to its outer side. One end of the cylindrical connecting rod is fixedly installed at a through hole on the main body, and the other end is fixedly connected to the cylindrical wall of the push rod compartment. A push rod spring is fitted over the push rod and installed inside the cylindrical connecting rod. The cam motor is fixedly installed inside the push rod compartment, and the cam motor shaft of the cam motor is fixedly connected to a cam, thus the rotation of the cam motor shaft drives the cam to rotate. The length adjustment assembly includes two sets of motor assemblies: a projectile motor and a projectile tail motor. The projectile motor is fixedly mounted on the cylindrical end face at the front end of the top rod compartment. The projectile motor has a projectile motor shaft, which is connected to a projectile screw. The projectile screw engages with a projectile threaded hole on the projectile. Rotation of the projectile motor shaft drives the projectile screw to rotate, thereby causing the projectile to move along the axial direction of the body. The projectile tail motor is fixedly mounted on the cylindrical end face at the other end of the top rod compartment. The projectile tail motor has a projectile tail motor shaft, which is connected to a projectile tail screw. The projectile tail screw engages with a projectile tail threaded hole on the projectile tail. Rotation of the projectile tail motor shaft drives the projectile tail screw to rotate, thereby causing the projectile tail to move along the axial direction of the body.

2. The projectile with adjustable length and variable structure according to claim 1, characterized in that, The body is provided with a head anti-rotation groove and a tail anti-rotation groove. The anti-rotation groove is used to limit the rotation of the head and tail relative to the body. A gap is provided between the outer surface of the projectile belt and the body. Four through holes are opened on the body cylinder wall opposite to the center position of the projectile belt for the top rod in the positioning assembly to pass through.

3. The projectile with adjustable length and variable structure according to claim 2, characterized in that, The projectile consists of a cylindrical section and an elliptical conical section. A threaded hole for the projectile is opened at the central axis of the bottom surface of the cylindrical section. A projectile anti-rotation pin is provided on the side wall of the cylindrical section of the projectile, which cooperates with the projectile anti-rotation groove.

4. The projectile with adjustable length and variable structure according to claim 2, characterized in that, The projectile tail includes a cylindrical section and a frustum end. A threaded hole for the projectile tail is opened at the central axis of the bottom surface of the cylindrical section. A projectile tail anti-rotation pin is provided on the side wall of the cylindrical section of the projectile tail, which cooperates with the projectile tail anti-rotation groove.

5. The projectile with adjustable length and variable structure according to claim 1, characterized in that, A connecting rod baffle is provided at one end of the cylindrical connecting rod near the spring belt; the side wall of the top rod compartment has a hole, and the position of the corresponding hole is connected to the cylindrical connecting rod.

6. The projectile with adjustable length and variable structure according to claim 5, characterized in that, The push rod includes a push rod body, a push rod head, a push rod protrusion, and a push rod tail end; the push rod head mates with a round hole-shaped spring band groove for spring band limiting; the push rod protrusion connects one end of the push rod spring, the other end of the push rod spring connects to the connecting rod baffle, and the push rod tail end contacts the outer contour line of the cam.

7. The projectile with adjustable length and variable structure according to claim 1, characterized in that, The fixed plate of the control compartment is also equipped with a speed sensor, a controller and a power supply. The speed sensor is used to collect the speed signal of the projectile; the controller is used to control the timing and duration of the motor unit's drive.

8. The projectile with adjustable length and variable structure according to claim 6, characterized in that, The cam has a four-part structure, consisting of four convex parts and four concave parts.

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