A parachute capture net closing device

Abstract

The application provides a net rope closing device for a flying net capture, comprising an energy storage mechanism, a speed reduction and torque increasing mechanism, a rope winding mechanism and a trigger release mechanism. The energy storage mechanism stores elastic potential energy and outputs rotary power when released; the speed reduction and torque increasing mechanism converts the high rotation speed and low torque output by the energy storage mechanism into low rotation speed and high torque to drive the rope winding mechanism to wind the flying net rope; the trigger release mechanism adopts a pure mechanical passive trigger mode, is unlocked when the flying net is pulled, and drives the rope winding shaft to wind the closing rope to realize net mouth closing after speed reduction and torque increasing. The application realizes complete passive trigger, sufficient closing pulling force and controllable speed, and is suitable for space debris removal and the like.

Description

Technical Field

[0001] This invention belongs to the field of space debris removal and aerospace technology, specifically relating to a net rope retraction device for capturing flying nets. Background Technology

[0002] In recent years, with the increasing frequency of space activities, the amount of space debris has grown exponentially. A large amount of space debris floats and spins in orbit, posing a serious threat to the safety of spacecraft in operation. Active removal of space debris has become a crucial issue that urgently needs to be addressed in the aerospace field.

[0003] The space net capture system is a crucial method for the active removal of space debris. Compared to traditional robotic arm capture methods, it offers advantages such as a wider capture range, longer capture distance, less impact on the carrier spacecraft, higher safety, and lower energy consumption. A typical space net capture system consists of a parent satellite, a launch system, a large-size flexible net, a closing mechanism, and a tethered control system. Its working principle is as follows: the launcher propels the closing device and mass block at a specific speed and angle, carrying the flexible net which unfolds in the target area and envelops the space debris. The closing mechanism then activates, tightening and locking the net opening, thus capturing the space debris. The closing mechanism is a critical guarantee for the successful capture of the space net; its design directly affects the feasibility and mission success rate of the entire space net capture system.

[0004] Existing net-closing devices mainly include motor-driven, pyrotechnic-driven, and spring-energy-storage types. Among them, the spring-energy-storage type has attracted attention because it does not require an external power source. However, existing spring-energy-storage solutions have the following shortcomings: (i) Uncontrollable retraction speed. When the spring directly drives the retraction mechanism, the spring has the largest torque and the highest rotation speed in the initial stage of release. The retraction rope tightens suddenly at a high speed, which will generate a large impact load on the net and the captured target. In the microgravity environment of space, this may cause the net to rebound, the target to escape again, or even damage the net or the target.

[0005] (ii) Insufficient closing tension. Due to the limited volume and mass of the elastic energy storage component, its output driving torque is limited. When the net opening size is large, the closing rope path is long, or there is significant friction between the net opening and the target, the tension directly driven by the elastic energy storage component may not be sufficient to overcome the resistance and achieve complete closing.

[0006] (iii) The elastic energy storage component is directly coupled to the closing rope, resulting in poor design flexibility. The speed-torque characteristics of the elastic energy storage component are difficult to match directly with the tension-speed characteristics required for closing. The design can only accommodate the characteristics of the elastic energy storage component and cannot be optimized for closing conditions.

[0007] For example, Chinese patent CN109204892B discloses a spring-energy-storing net-gathering device, which includes a series-connected spring energy-storing mechanism, a rope wheel gathering mechanism, a synchronous gear mechanism, a trigger locking mechanism, and a control circuit board. When winding, the spring shaft is manually rotated to wind and store energy. When gathering, the control circuit board energizes the push-pull electromagnet. The electromagnet push rod retracts to release the rope wheel. The rope wheel rotates under the elastic force of the spring to gather the line. The two rope wheels rotate in opposite directions synchronously through the bevel gear synchronous mechanism to achieve the gathering of the line. This solution still has the following shortcomings: (1) The trigger locking depends on the control circuit board and the push-pull electromagnet, which requires power supply and control circuit support. The device is heavy and the system is complex. It is not reliable in passive environments such as space vacuum, strong radiation, and high and low temperature alternation. (2) The spring directly drives the rope wheel to gather the line. The speed is the highest and the torque is the largest in the initial stage of spring release. The gathering impact is large and the speed is uncontrollable. Moreover, it is limited by the output torque of the spring. When facing a large net opening or large frictional resistance, the gathering pull is insufficient.

[0008] Existing motor-driven solutions rely on external energy and control circuits, making them unsuitable for passive space scenarios; pyrotechnic solutions pose safety hazards and have excessive impact at the closing point.

[0009] Therefore, there is an urgent need for a closing device that can provide sufficient closing tension, control closing speed, and maintain completely passive triggering. Summary of the Invention

[0010] Purpose of the invention: In order to overcome the above shortcomings, the present invention provides a net rope retraction device for net capture, which adopts a purely mechanical passive triggering method. The entire triggering chain does not involve any circuit, motor or electromagnet, achieving complete passivity; while providing sufficient retraction force, it precisely controls the retraction speed and avoids retraction impact.

[0011] Technical Solution: To achieve the above objectives, this invention provides a net rope retraction device for net capture, comprising an energy storage mechanism, a deceleration and torque amplification mechanism, a rope winding mechanism, and a trigger release mechanism. The energy storage mechanism stores elastic potential energy and outputs rotational power upon release. The deceleration and torque amplification mechanism reduces the rotational speed, increases the torque, and transmits the power to the rope winding mechanism. The rope winding mechanism winds up the net rope to achieve net retraction. The trigger release mechanism passively controls the release of the energy storage mechanism, causing the net to automatically retract after retraction.

[0012] Furthermore, in the above-mentioned net rope closing device for net capture, the energy storage mechanism includes an elastic energy storage element and an energy storage shaft. The elastic energy storage element is driven to connect with the energy storage shaft. The elastic energy storage element stores energy when the energy storage shaft rotates and releases it when the energy storage shaft rotates back.

[0013] Furthermore, in the aforementioned net-catching rope-gathering device, the deceleration and torque-increasing mechanism is a reduction gear set. The input end of the reduction gear set is connected to the energy storage shaft, and its output end is connected to the rope-winding mechanism. The rope-winding mechanism includes a rope-winding shaft and a gathering rope connected to the rope-winding shaft. The rope-winding shaft is driven to the output end of the reduction gear set, and the gathering rope is threaded along the opening of the net.

[0014] Furthermore, in the aforementioned net-catching rope retraction device, the trigger release mechanism includes a locking module and a trigger pull rope. The locking module releasably keeps the energy storage mechanism in an energy storage state. The trigger pull rope is connected to the locking module, and triggers the locking module to release the lock when the net is pulled.

[0015] Furthermore, in the aforementioned net-catching rope retraction device, the locking module includes a locking pin, a locking release assembly, and a connecting rope. The locking pin is inserted radially along the energy storage shaft, with its inner end inserted into the limiting hole between the energy storage mechanism and the deceleration and torque-increasing mechanism, and the inner end of the locking pin abuts against the energy storage shaft. The outer end of the locking pin is fixedly connected to one end of the trigger pull rope. The end of the trigger pull rope away from the locking pin is connected to the opening of the net. The locking release assembly abuts against the outer end of the locking pin, locking the locking pin in the limiting hole and applying a locking force towards the energy storage shaft. One end of the connecting rope is fixedly connected to the locking pin, and the other end is fixed to the housing of the energy storage mechanism or the deceleration and torque-increasing mechanism. The trigger pull rope is used to separate the locking pin from the energy storage shaft when the net is pulled.

[0016] Furthermore, in the aforementioned net-catching rope retraction device, the locking release assembly includes a pressure block, an elastic pressure member, and a limiting member. The pressure block is slidably disposed between the energy storage mechanism and the deceleration and torque-increasing mechanism to move closer to or further away from the locking pin. The limiting member is fixed between the energy storage mechanism and the deceleration and torque-increasing mechanism. The two ends of the elastic pressure member abut against the pressure block and the limiting member, respectively. The elastic pressure member applies pressure to the pressure block, causing the pressure block to move towards the locking pin to lock it.

[0017] Furthermore, in the aforementioned net-catching rope retraction device, the outer end of the locking pin is provided with a first conical surface. The end of the pressure block that abuts against the locking pin is provided with a second conical surface. The first conical surface and the second conical surface are adapted to each other, so that the pressure block applies a thrust toward the energy storage shaft to the locking pin.

[0018] Furthermore, in the above-mentioned net rope closing device for capturing flying nets, the two ends of the closing rope are respectively fixed to the rope winding shaft. When the rope winding shaft rotates, the two ends of the closing rope are wound synchronously, causing the opening of the flying net to shrink radially.

[0019] Furthermore, in the aforementioned net-catching rope retraction device, the elastic energy storage element is a planar spiral spring. The energy storage mechanism also includes a spring housing, in which the elastic energy storage element is disposed, with its outer end fixedly connected to the inner wall of the spring housing and its inner end fixedly connected to the energy storage shaft.

[0020] Furthermore, the aforementioned net rope tightening device for net capture also includes a mass block, which is fixedly connected to an energy storage mechanism or a deceleration and torque amplification mechanism. The mass block provides an anchor point for the rope winding mechanism to tighten the net opening. By setting the mass block to provide an inertial anchor point for the rope winding mechanism, the reaction force is absorbed during the tightening process, stabilizing the device's attitude and concentrating the tightening force on the net rope winding rather than the overall displacement of the device, thereby improving tightening efficiency and reliability.

[0021] As can be seen from the above technical solution, the present invention has the following beneficial effects: ①The present invention provides a net rope retraction device for net capture. By setting a deceleration and torque amplification mechanism, the high-speed, low-torque power stored in the elastic energy storage component is converted into a low-speed, high-torque output to drive the rope winding shaft to stably wind up the retraction rope. The retraction torque is large and continuously stable, avoiding the impact load caused by excessively high initial speed when the elastic energy storage component is directly driven. This effectively prevents material overload or structural damage to the net body caused by sudden tightening, avoids escape or secondary damage to the wrapped target due to impact, and reduces the risk of the retraction rope breaking due to impact. It is suitable for capturing high-value targets.

[0022] ② The net rope retraction device for net capture of the present invention decouples the elastic energy storage component from the retraction requirements through a deceleration and torque amplification mechanism. This allows the design of the elastic energy storage component to focus only on energy storage density and total energy, while the tension-speed characteristics of the retraction end can be flexibly adjusted by selecting reduction gear sets with different transmission ratios. Based on specific working conditions such as net size, target mass, and retraction rope path, the optimal transmission ratio can be selected to achieve customized optimization of retraction performance without redesigning the elastic energy storage component.

[0023] ③ This invention achieves purely mechanical triggering release and energy storage drive by triggering the pull rope when the net is pulled, which drives the locking pin to disengage from the energy storage shaft. It does not require an external power supply or electronic control system, and achieves a completely passive closing mechanism. It has fast triggering response, high reliability, and is suitable for extreme environments such as vacuum, strong radiation, and alternating high and low temperatures. Attached Figure Description

[0024] Figure 1 This is a schematic diagram of the net rope closing device for net capture according to the present invention; Figure 2 This is an exploded view of the net rope closing device for net capture according to the present invention; Figure 3 This is a schematic diagram of the locking module.

[0025] In the diagram: 1. Energy storage mechanism, 11. Elastic energy storage component, 12. Energy storage shaft, 13. Spring housing, 14. Limiting hole, 2. Deceleration and torque amplification mechanism, 3. Trigger release mechanism, 31. Trigger pull rope, 32. Locking pin, 33. Locking release assembly, 331. Pressure block, 332. Elastic pressure component, 333. Limiting component, 34. Connecting rope, 4. Winding shaft, 5. Mass block. Detailed Implementation Example

[0026] like Figure 1 The above-displayed net rope retraction device for net capture includes an energy storage mechanism 1, a deceleration and torque amplification mechanism 2, a rope winding mechanism, and a trigger release mechanism 3.

[0027] Energy storage mechanism 1 stores elastic potential energy and outputs rotational power upon release. Speed ​​reduction and torque amplification mechanism 2 reduces rotational speed, increases torque, and transmits power to the rope winding mechanism. The rope winding mechanism winds up the net rope to achieve net winding. Trigger release mechanism 3 passively controls the release of energy storage mechanism 1, causing the net to automatically wind up after the opening is closed.

[0028] like Figure 2-3 The shown net-catching net rope retraction device includes an energy storage mechanism 1 comprising an elastic energy storage element 11 and an energy storage shaft 12. The elastic energy storage element 11 is drivenly connected to the energy storage shaft 12. The elastic energy storage element 11 stores energy when the energy storage shaft 12 rotates and releases energy when the energy storage shaft 12 rotates back. The elastic energy storage element 11 is a planar spiral spring. The energy storage mechanism 1 also includes a spring housing 13, in which the elastic energy storage element 11 is disposed. Its outer end is fixedly connected to the inner sidewall of the spring housing 13, and its inner end is fixedly connected to the energy storage shaft 12. In the initial state, the elastic energy storage element 11 is twisted to store energy and has a tendency to return to its natural state.

[0029] In this embodiment, the speed reduction and torque amplification mechanism 2 is a speed reduction gear set. The input end of the speed reduction gear set is connected to the energy storage shaft 12 via a coupling (in this embodiment, the connection is made via a coupling), and the output end of the speed reduction gear set is connected to the rope winding mechanism. The rope winding mechanism includes a rope winding shaft 4 and a take-up rope connected to the rope winding shaft 4. The rope winding shaft 4 is driven to the output end of the speed reduction gear set, and the take-up rope is threaded along the opening of the net. The speed reduction gear set is a planetary gear set with a high transmission ratio, used to convert the high speed and low torque of the energy storage shaft 12 into the low speed and high torque of the rope winding shaft 4.

[0030] In this embodiment, the closing rope is a high-strength ultra-high molecular weight polyethylene rope. The two ends of the closing rope are fixed to the rope winding shaft 4 respectively. After the middle part of the closing rope is led out from the rope winding shaft 4, it is threaded around the circumference of the net opening. When the rope winding shaft 4 rotates, it synchronously winds the two ends of the closing rope. As the closing rope is wound on the rope winding shaft 4, the net opening shrinks radially.

[0031] In this embodiment, the trigger release mechanism 3 includes a locking module and a trigger pull rope 31. The locking module releasably keeps the energy storage mechanism 1 in an energy storage state. The trigger pull rope 31 is connected to the locking module, and the locking module is triggered to release the lock when the net is pulled.

[0032] like Figure 3 The shown net-catching cable closing device includes a locking module comprising a locking pin 32, a locking release assembly 33, and a connecting rope 34. The locking pin 32 is inserted radially along the energy storage shaft 12, with its inner end inserted into the limiting hole 14 between the energy storage mechanism 1 and the deceleration and torque amplification mechanism 2. The inner end of the locking pin 32 abuts against the energy storage shaft 12, locking the energy storage shaft 12 and preventing the release of the elastic energy storage element 11. The outer end of the locking pin 32 is fixedly connected to one end of the trigger pull rope 31. The end of the trigger pull rope 31 away from the locking pin 32 is connected to the net opening. The locking release assembly 33 abuts against the outer end of the locking pin 32, locking the locking pin 32 within the limiting hole 14 and applying a locking force towards the energy storage shaft 12 to the locking pin 32. One end of the connecting rope 34 is fixedly connected to the locking pin 32, and the other end is fixed to the housing of the energy storage mechanism 1 or the deceleration and torque amplification mechanism 2. The trigger pull rope 31 is used to separate the locking pin 32 from the energy storage shaft 12 when the net is pulled.

[0033] In this embodiment, the locking release assembly 33 includes a pressure block 331, an elastic pressure member 332, and a limiting member 333. The pressure block 331 is slidably disposed between the energy storage mechanism 1 and the deceleration and torque amplification mechanism 2 to move closer to or further away from the locking pin 32. The limiting member 333 is fixed between the energy storage mechanism 1 and the deceleration and torque amplification mechanism 2. The two ends of the elastic pressure member 332 abut against the pressure block 331 and the limiting member 333, respectively. The elastic pressure member 332 applies pressure to the pressure block 331, causing the pressure block 331 to move toward the locking pin 32 to lock the locking pin 32.

[0034] In this embodiment, the outer end of the locking pin 32 is provided with a first conical surface. The end of the pressure block 331 that abuts against the locking pin 32 is provided with a second conical surface. The first conical surface and the second conical surface are adapted to each other, so that the pressure block 331 applies a pushing force to the energy storage shaft 12 to the locking pin 32. Since the locking pin 32 is located on the side of the energy storage shaft 12, the torque on the energy storage shaft 12 is small, the locking force required for the locking pin 32 is small, the shear force it bears is small, the pull-out force is low, and the triggering is sensitive.

[0035] In this embodiment, a mass block 5 is also included. The mass block 5 is fixedly connected to the energy storage mechanism 1 or the deceleration and torque amplification mechanism 2. The mass block 5 provides an anchor point for the rope winding mechanism to tighten the net opening. The mass block 5 is used to increase the mass and inertia of the device, increase the initial kinetic energy of the projectile, and ensure the stability of the launch speed and flight direction. During the capture and closing process, after the flying net wraps around the target, the mass block 5 keeps the device in a stable position in space and prevents it from being dragged and drifting by the net. As an inertial anchor point, it provides reverse support force for the closing rope to tighten the net opening, ensuring a smooth closing process.

[0036] The working principle of this embodiment is as follows: Before the net is launched, the locking pin 32 is in the disengaged state. The operator rotates the rope winding shaft 4 using an external tool. The rope winding shaft 4 drives the energy storage shaft 12 to rotate through the reduction gear set of the reduction and torque amplification mechanism 2, causing the elastic energy storage element 11 to twist and store energy. After the winding is completed, the locking pin 32 is inserted into the limiting hole 14. The elastic pressure element 332 of the locking release component 33 pushes the pressure block 331. The pressure block 331 applies a thrust towards the energy storage shaft 12 through the first conical surface and the second conical surface. The locking pin 32 abuts against the energy storage shaft 12, locking the energy storage shaft 12 and keeping the elastic energy storage element 11 in the energy storage state.

[0037] After the net is launched, the device carrying the net flies and unfolds under the action of the initial launch velocity. When the net wraps around space debris in space, the net is pulled by the target and pulls the trigger cord 31. The trigger cord 31 drives the locking pin 32 to move radially outward against the locking force of the elastic pressure member 332, so that the locking pin 32 separates from the energy storage shaft 12 and releases the lock on the energy storage shaft 12.

[0038] After the energy storage shaft 12 is unlocked, the elastic energy storage element 11 releases its elastic potential energy, driving the energy storage shaft 12 to rotate at a higher speed. The rotation of the energy storage shaft 12 is reduced in speed and increased in torque by the deceleration and torque amplification mechanism 2 before being transmitted to the rope winding shaft 4. When the rope winding shaft 4 rotates, the closing rope is synchronously wound onto the winding shaft 4, so that the closing rope is tightened evenly at a stable and controllable speed. During this closing process, the mass block 5 fixed on the device increases the mass and inertia of the device, and acts as an inertial anchor point to provide reverse support force for the tightening of the closing rope, ensuring that the closing is completed smoothly.

[0039] The above embodiments are exemplary and are intended to illustrate the technical concept and features of the present invention, so that those skilled in the art can understand the content of the present invention and implement it accordingly. They should not be construed as limiting the scope of protection of the present invention. All equivalent changes or modifications made according to the spirit and essence of the present invention should be covered within the scope of protection of the present invention.

Claims

1. A net rope retraction device for catching birds with a flying net, characterized in that: It includes an energy storage mechanism (1), a deceleration and torque amplification mechanism (2), a rope winding mechanism, and a trigger release mechanism (3); the energy storage mechanism (1) is used to store elastic potential energy and output rotational power when released; the deceleration and torque amplification mechanism (2) is used to reduce the rotational speed, increase the torque, and transmit the power to the rope winding mechanism; the rope winding mechanism is used to wind up the flying net rope to realize the flying net winding; the trigger release mechanism (3) passively controls the release of the energy storage mechanism (1) so that the flying net is automatically wound up after the opening is closed.

2. The net rope closing device for net capture according to claim 1, characterized in that: The energy storage mechanism (1) includes an elastic energy storage element (11) and an energy storage shaft (12). The elastic energy storage element (11) is driven to connect with the energy storage shaft (12). The elastic energy storage element (11) stores energy when the energy storage shaft (12) rotates and releases energy when the energy storage shaft (12) rotates back.

3. The net rope closing device for net capture according to claim 2, characterized in that: The deceleration and torque-increasing mechanism (2) is a deceleration gear set. The input end of the deceleration gear set is connected to the energy storage shaft (12) and its output end is connected to the rope winding mechanism. The rope winding mechanism includes a rope winding shaft (4) and a closing rope connected to the rope winding shaft (4). The rope winding shaft (4) is driven to the output end of the deceleration gear set, and the closing rope is threaded along the opening of the flying net.

4. The net rope closing device for net capture according to claim 2, characterized in that: The trigger release mechanism (3) includes a locking module and a trigger pull rope (31). The locking module releases the energy storage mechanism (1) into an energy storage state. The trigger pull rope (31) is connected to the locking module and triggers the locking module to release the lock when the net is pulled.

5. The net rope closing device for net capture according to claim 4, characterized in that: The locking module includes a locking pin (32), a locking release component (33), and a connecting rope (34). The locking pin (32) is inserted radially along the energy storage shaft (12), with its inner end inserted into the limiting hole (14) between the energy storage mechanism (1) and the deceleration and torque amplification mechanism (2). The inner end of the locking pin (32) abuts against the energy storage shaft (12). The outer end of the locking pin (32) is fixedly connected to one end of the trigger pull rope (31). The end of the trigger pull rope (31) away from the locking pin (32) is connected to the opening of the flying net. Connection; the locking release assembly (33) abuts against the outer end of the locking pin (32), locking the locking pin (32) in the limiting hole (14) and applying a locking force to the locking pin (32) in the direction of the energy storage shaft (12); one end of the connecting rope (34) is fixedly connected to the locking pin (32), and the other end is fixed to the housing of the energy storage mechanism (1) or the deceleration and torque amplification mechanism (2); the trigger pull rope (31) is used to separate the locking pin (32) from the energy storage shaft (12) when the flying net is pulled.

6. The net rope closing device for net capture according to claim 5, characterized in that: The locking release assembly (33) includes a pressure block (331), an elastic pressure member (332), and a limiting member (333). The pressure block (331) is slidably disposed between the energy storage mechanism (1) and the deceleration and torque amplification mechanism (2) to move closer to or further away from the locking pin (32). The limiting member (333) is fixed between the energy storage mechanism (1) and the deceleration and torque amplification mechanism (2). The two ends of the elastic pressure member (332) abut against the pressure block (331) and the limiting member (333) respectively. The elastic pressure member (332) applies pressure to the pressure block (331), causing the pressure block (331) to move toward the locking pin (32) to lock the locking pin (32).

7. The net rope closing device for net capture according to claim 6, characterized in that: The outer end of the locking pin (32) is provided with a first conical surface; the end of the pressure block (331) that abuts against the locking pin (32) is provided with a second conical surface; the first conical surface and the second conical surface are adapted to each other so that the pressure block (331) applies a thrust to the energy storage shaft (12) to the locking pin (32).

8. The net rope closing device for net capture according to claim 3, characterized in that: The two ends of the closing rope are respectively fixed to the rope winding shaft (4). When the rope winding shaft (4) rotates, it will simultaneously wind the two ends of the closing rope, causing the opening of the flying net to shrink radially.

9. The net rope closing device for net capture according to claim 2, characterized in that: The elastic energy storage component (11) is a planar spiral spring; the energy storage mechanism (1) also includes a spring housing (13), the elastic energy storage component (11) is disposed inside the spring housing (13), its outer end is fixedly connected to the inner side wall of the spring housing (13), and its inner end is fixedly connected to the energy storage shaft (12).

10. The net rope closing device for net capture according to claim 1, characterized in that: It also includes a mass block (5), which is fixedly connected to the energy storage mechanism (1) or the deceleration and torque amplification mechanism (2), and the mass block (5) provides an anchor point for the rope winding mechanism to tighten the net opening.

Images