Folding bounce-off two-way limiting mechanism for patrolling bomb

Abstract

A folding bounce-off two-way limiting mechanism for a patrolling bomb comprises a bounce-off device, a transverse upper limit limiting device and a thrust device. The flicking device comprises an L-shaped base, a cylindrical spiral spring, an aluminum alloy gasket and a single-side threaded rod. The transverse upper limit limiting device comprises an aluminum alloy locking fixing ring sleeve, an aluminum alloy hollow pipe, a spring plunger and a metal propeller hub. The thrust device comprises a rigid flange plate and a silica gel protective sleeve; the aluminum alloy hollow pipe, the locking fixing ring sleeve and the spring plunger are relatively and fixedly installed at the position of the positioning penetrating hole, a ball head of the spring plunger penetrates out of the positioning penetrating hole and is limited by the single-side threaded rod to pop out, and after external constraint is canceled, the aluminum alloy locking fixing ring sleeve, the aluminum alloy hollow pipe and the spring plunger slide out of the single-side threaded rod at the same time. The aluminum alloy hollow pipe is ensured not to return, so that one-way locking is realized; the device has the characteristics of modularization, easiness in disassembly and assembly, light weight, reliable structure and effective and quick response.

Description

Technical Field

[0001] This invention belongs to the field of propeller-driven loitering munition technology, specifically relating to a folding and opening bidirectional limiting mechanism for loitering munitions. Background Technology

[0002] Propeller-driven loitering munitions are loitering munitions powered by a piston engine and a propeller. Their core characteristics are long endurance and slow flight speed. They are designed for dual functions of "reconnaissance and low-cost strike". To achieve a larger payload and more efficient combat, propeller folding technology is particularly important for loitering munitions.

[0003] The technology for folding propellers is relatively mature, but each technology has its own advantages and disadvantages. One such technology, called an automatic folding mechanism for drone propellers (CN116853559A), can achieve fully automated folding, but relies on elastic bands with limited lifespan, resulting in insufficient reliability. Another technology, called a foldable drone propeller (CN110027699A), uses a rigid double-support frame design to withstand high-speed airflow, but requires manual folding and introduces significant structural weight. A foldable propeller capable of withstanding high-speed airflow (CN112124567A) has strong adaptability to high-speed airflow and an automatic unfolding mechanism, but its structure is relatively complex, and material and manufacturing costs are high. A foldable drone propeller based on springs (CN120057327A) has fast response characteristics and high reliability; however, the lifespan of the springs is very short in the high-load, complex stress environment of propeller operation. Summary of the Invention

[0004] To overcome the shortcomings of the prior art, the purpose of this invention is to provide a folding and opening bidirectional limiting mechanism for loitering munitions, which features modularity, easy assembly and disassembly, light weight, reliable structure, and effective and rapid response.

[0005] To achieve the above objectives, the technical solution adopted by the present invention is: a folding and opening bidirectional limiting mechanism for loitering munitions, comprising an opening device, a lateral upper limit limiting device, and a thrust device. The spring-opening device includes: an L-shaped base, a cylindrical helical spring, an aluminum alloy washer, and a single-sided threaded rod; The cylindrical helical spring is embedded and fixed at both ends on an L-shaped base and an aluminum alloy washer, respectively. The aluminum alloy washer is used to evenly transmit the spring force, and the threaded end of the single-sided threaded rod is completely screwed into the threaded hole of the L-shaped base. The lateral upper limit limiting device includes an aluminum alloy stop fixing ring, an aluminum alloy hollow tube, a spring plunger, and a metal propeller hub connector. The spring plunger is embedded in the aluminum alloy stop and fixation ring sleeve, which is sleeved on the aluminum alloy hollow tube according to the preset hole position. The metal paddle hub is independently restricted in one direction by its own top baffle. The thrust device includes a rigid flange and a silicone protective sleeve; the rigid flange is connected to the outermost end of the aluminum alloy hollow tube; the silicone protective sleeve is fitted over the end of the rigid flange.

[0006] The L-shaped base is adapted to the hub of a single-engine propeller. One end of the L-shaped base has a round hole, which is fastened to the metal hub connector by bolts. The other end is close to the central rotating shaft. The L-shaped base has a built-in threaded hole. The aluminum alloy hollow tube is sleeved on the single-sided threaded rod body, and the spring plunger is connected to the internal thread of the stop and fixing ring through the external thread. The stop and fixing ring is sleeved on the aluminum alloy hollow tube. The aluminum alloy hollow tube has a positioning hole at the limit position where it engages with the stop and fixing ring when the cylindrical helical spring is in a pre-compressed state. This allows the aluminum alloy hollow tube, the stop and fixing ring, and the spring plunger to be relatively fixed in the positioning hole. The ball head of the spring plunger passes through the positioning hole and is ejected by the rod body of the single-sided threaded rod. After the external constraint is removed, the aluminum alloy stop and fixing ring, the aluminum alloy hollow tube, and the spring plunger slide out of the single-sided threaded rod simultaneously until the spring plunger reaches the end face of the rod body and ejects, preventing the aluminum alloy hollow tube from returning and achieving one-way locking. Locking in the other direction can be achieved by the baffle of the propeller hub itself.

[0007] The rigid flange is connected to the outermost end of the aluminum alloy hollow tube by adhesive or bolts.

[0008] The beneficial effects of this invention are: Compared with the prior art, the present invention uses an L-shaped base as the base, which can be well adapted to the propeller hub and is easy to disassemble and assemble by using a separation surface; the spring-opening device, the lateral locking structure and the thrust structure are mainly composed of standard parts, which can reduce processing costs and facilitate maintenance and replacement. The entire system is compact and occupies little space. The main components are made of lightweight aluminum alloy and have a simple structure. It is lighter than the traditional folding and opening two-way limiting mechanism, which effectively reduces the extra load of the loitering munition. The pop-out mechanism enables the propellers to unfold automatically, and the time from unlocking to full unfolding is only a few seconds, which is faster than the manual folding and pop-out two-way limit mechanism. This invention features easy assembly and disassembly, reliable structure, modularity, low cost, and light weight. Attached Figure Description

[0009] Figure 1This is a partial structural diagram of the area where the propeller of the foldable propeller loitering munition is located.

[0010] Figure 2 This is a schematic diagram of a propeller-driven loitering munition with its propeller in a folded state.

[0011] Figure 3 yes Figure 1 Schematic diagram of the L-shaped base.

[0012] Figure 4 yes Figure 1 Schematic diagram of the connection structure between the metal propeller hub connector and the L-shaped base.

[0013] Figure 5 yes Figure 1 A schematic diagram of the central propeller hub, upper limit stop, and folding / springing bidirectional limit mechanism.

[0014] Figure 6 yes Figure 1 A schematic diagram of the assembly structure of the folding and unfolding bidirectional limiting mechanism of the loitering munition before folding, excluding the metal propeller hub connector.

[0015] Figure 7 yes Figure 1 A schematic diagram of the assembly structure of the folding and unfolding bidirectional limiting mechanism of the loitering munition after folding, excluding the metal propeller hub connector.

[0016] Figure 8 yes Figure 5 A partially transparent structural diagram of the spring plunger limiting mechanism.

[0017] Figure 9 yes Figure 8 Schematic diagram of the transparent structure.

[0018] Figure 10 yes Figure 5 Schematic diagrams of the structure of various standard parts.

[0019] In the diagram: 1-Metal propeller hub connector; 2-Propeller blade; 3-L-shaped base; 4-Cylindrical helical spring; 5-Single-sided threaded rod; 6-Aluminum alloy gasket; 7-Aluminum alloy hollow tube; 8-Aluminum alloy retaining ring; 9-Spring plunger; 10-Rigid flange; 11-Silicone protective sleeve; 12-Motor shaft. Detailed Implementation

[0020] The structural and working principles of the present invention will be further described in detail below with reference to the accompanying drawings and embodiments.

[0021] All standard parts used in this invention can be purchased from the market, and irregular parts can be customized according to the description and drawings. The specific connection methods of each part adopt conventional methods such as bolts, welding, and bonding that are mature in the prior art, and will not be described in detail here.

[0022] See Figure 1-6 A folding and opening two-way limiting mechanism for loitering munitions, comprising an opening device, a lateral upper limit limiting device, and a thrust device. The spring-opening device includes: an L-shaped base 3, a cylindrical helical spring 4, an aluminum alloy washer 6, and a single-sided threaded rod 5; the L-shaped base 3 is adapted to the hub of a single-engine propeller, one end of the L-shaped base 3 is provided with a round hole, which is fastened to the hub by bolts. The specific size should be adapted to the specific hub slot to ensure reliable fixation, and the other end is close to the central rotating shaft. The L-shaped base 3 has a built-in threaded hole. The cylindrical helical spring 4 is embedded and fixed at both ends on the L-shaped base 3 and the aluminum alloy washer 6, respectively. The aluminum alloy washer 6 is used to evenly transmit the spring force. The threaded end of the single-sided threaded rod 5 is completely screwed into the threaded hole of the L-shaped base 3. The lateral upper limit limiting device includes an aluminum alloy stop and fixing ring 8, an aluminum alloy hollow tube 7, a spring plunger 9, and a metal propeller hub connector 1. The spring plunger 9 is embedded in the aluminum alloy stop and fixation ring 8, and the aluminum alloy stop and fixation ring 8 is sleeved on the aluminum alloy hollow tube 7 according to the preset hole position. The metal paddle hub is independently restricted in one direction by its own top baffle. The aluminum alloy hollow tube 7 is sleeved on the single-sided threaded rod 5. The spring plunger 9 is connected to the internal thread of the stop and fixing ring 8 through the external thread. The stop and fixing ring 8 is sleeved on the aluminum alloy hollow tube 7. The movable fixing ring 8 is made of aluminum alloy. A positioning hole is set at the limit position where the aluminum alloy hollow tube 7 and the stop fixing ring 8 are engaged when the spring is in the pre-compressed state. This ensures that the aluminum alloy hollow tube 7, the stop fixing ring 8, and the spring plunger 9 are relatively fixedly installed in the positioning hole. The ball head of the spring plunger 9 passes through the positioning hole and is restricted by the rod body of the single-sided threaded rod 5 to pop out. After the external constraint is removed, the aluminum alloy stop fixing ring 8, the aluminum alloy hollow tube 7, and the spring plunger 9 slide out at the same time until the spring plunger 9 just reaches the end face of the rod body of the single-sided threaded rod 5 and pops out, ensuring that the aluminum alloy hollow tube 7 cannot return, thereby achieving one-way locking. Locking in the other direction can be achieved by the baffle of the metal paddle hub connector 1 itself. This invention will not be described separately. The thrust device includes a rigid flange 10 and a silicone protective sleeve 11. The rigid flange 10 is connected to the outermost end of the aluminum alloy hollow tube 7 by adhesive or bolt connection. When the centrifugal force is not large, adhesive is considered to reduce the structural weight. When the centrifugal force is too large, bolt connection is required. The silicone protective sleeve 11 is wrapped around the plate end of the rigid flange 10 to avoid damage to the propeller blade surface by the force application end of the spring mechanism as much as possible.

[0023] Example This embodiment includes propeller blades 2, metal hub connectors 1, a folding and opening bidirectional limiting mechanism, and a motor shaft 12 for a portion of the aircraft.

[0024] The loitering munition is placed inside a constraint cylinder. The metal hub connector 1 is mounted on the motor shaft 12. The propeller blades 2 are mounted on the left and right ends of the metal hub connector 1 in a hinged manner. By releasing one degree of rotational freedom, the propeller blades 2 are subject to an external constraint from the inner wall of the cylinder. The cylindrical helical spring 4 inside the folding and opening bidirectional limiting mechanism of the present invention is in a pre-compressed state. The folding and opening bidirectional limiting mechanism is connected and fixed to the metal propeller hub connector 1 through the L-shaped base 3; one end of the L-shaped base 3 is connected to the metal propeller hub connector 1, which also has corresponding through holes, by a bolt through a small hole, and the other end is tightly attached to the rotating shaft of the metal propeller hub connector 1 through its own cylindrical groove to transmit part of the pressure of the spring 4; the metal propeller hub connector 1 itself can be connected to the motor shaft 12 through a standard mechanical connection method. The L-shaped base 3 has a built-in threaded hole that is fastened to the threaded end of the single-sided threaded rod 5. The two ends of the cylindrical helical spring 4 are respectively fixed on the small holes opened in the L-shaped base 3 and the aluminum alloy gasket 6. In addition to the threaded hole, the L-shaped base 3 also has an annular groove with a certain depth to better accommodate the cylindrical helical spring 4. The working principle of this invention is: The aluminum alloy hollow tube 7 is sleeved on the single-sided threaded rod 5. The spring plunger 9 is connected to the aluminum alloy retaining ring 8 through external thread engagement. The spring plunger 9 can be installed on one or both sides according to actual needs. To reduce weight and space occupation, a small portion of the retaining ring 8 can be cut off (leaving the threaded hole) before being sleeved on the aluminum alloy hollow tube 7. A positioning hole is provided at the limit position where the aluminum alloy hollow tube 7 and the stop ring 8 are in the pre-compressed state. This ensures that the aluminum alloy hollow tube 7, the stop ring 8, and the spring plunger 9 are relatively fixed in the positioning hole. The ball head of the spring plunger 9 passes through the positioning hole and is restricted from popping out by the single-sided threaded rod 5. After the external constraint is removed, the three (aluminum alloy stop ring 8, aluminum alloy hollow tube 7, and spring plunger 9) slide out of the single-sided threaded rod 5 at the same time until the spring plunger 9 just reaches the smooth end face of the single-sided threaded rod 5 and pops out, ensuring that the aluminum alloy hollow tube 7 cannot return, thus achieving one-way locking. Locking in the other direction can be achieved by the top baffle of the metal hub connector 1 itself. When the propeller blade 2 rotates to the position of the designed rotation surface, the root of the blade just hits the top baffle of the metal hub connector 1, so it cannot rotate upwards.

[0025] After the external constraints of the cylinder are removed, the propeller blade 2 responds quickly and springs open under the pre-compression force of the cylindrical helical spring 4. When it reaches the upper limit position, the root of the propeller blade 2 is blocked by the top baffle of the metal hub connector 1 and cannot spring open further. At this time, the cylindrical helical spring 4 is still in a compressed state. However, when the propeller blade 2 is fully unfolded and enters the state of rotating around the central axis of the hub, due to the gravity of the propeller blade 2 itself, a back pressure force will be applied to the folding and opening bidirectional limiting mechanism. At this time, it is necessary to rely on the ball head of the spring plunger 9 to pop out and press against the smooth end face of the single-sided threaded rod 5 to achieve the self-locking function in the back pressure direction.

Claims

1. A folding, spring-loaded, bidirectional limiting mechanism for loitering munitions, characterized in that, It includes a spring-opening device, a lateral upper limit limiting device, and a thrust device; The spring-opening device includes: an L-shaped base (3), a cylindrical helical spring (4), an aluminum alloy washer (6), and a single-sided threaded rod (5); The cylindrical helical spring (4) is embedded and fixed at both ends on the L-shaped base (3) and the aluminum alloy washer (6), respectively. The aluminum alloy washer (6) is used to uniformly transmit the spring force. The threaded end of the single-sided threaded rod (5) is completely screwed into the threaded hole of the L-shaped base (3). The lateral upper limit device includes an aluminum alloy stop and fixing ring (8), an aluminum alloy hollow tube (7), a spring plunger (9), and a metal propeller hub connector (1). The spring plunger (9) is embedded in the aluminum alloy stop and fixation ring (8), and the aluminum alloy stop and fixation ring (8) is sleeved on the aluminum alloy hollow tube (7) according to the preset hole position. The metal paddle hub is independently restricted in one direction by its own top baffle. The thrust device includes a rigid flange (10) and a silicone protective sleeve (11); the rigid flange (10) is connected to the outermost end of the aluminum alloy hollow tube (7); the silicone protective sleeve (11) is sleeved on the end of the rigid flange (10).

2. The folding and unfolding bidirectional limiting mechanism for a loitering munition according to claim 1, characterized in that, The L-shaped base (3) is adapted to the hub of a single-engine propeller. One end of the L-shaped base (3) has a round hole and is fastened to the metal hub connector (1) by bolts. The other end is close to the central rotating shaft. The L-shaped base (3) has a built-in threaded hole.

3. The folding and unfolding bidirectional limiting mechanism for a loitering munition according to claim 1, characterized in that, The aluminum alloy hollow tube (7) is sleeved on the single-sided threaded rod (5), and the spring plunger (9) is connected to the internal thread of the stop fixing ring (8) through the external thread. The stop fixing ring (8) is sleeved on the aluminum alloy hollow tube (7).

4. A folding and unfolding bidirectional limiting mechanism for a loitering munition according to claim 1, characterized in that, The aluminum alloy hollow tube (7) is provided with a positioning hole at the limit position where it cooperates with the stop and fixing ring when the cylindrical helical spring (4) is in the pre-compression state. The aluminum alloy hollow tube (7), the stop and fixing ring (8), and the spring plunger (9) are relatively fixedly installed in the positioning hole. The ball head of the spring plunger (9) passes through the positioning hole and is restricted by the rod body of the single-sided threaded rod (5) to pop out. After the external constraint is removed, the aluminum alloy stop and fixing ring, the aluminum alloy hollow tube, and the spring plunger slide out of the single-sided threaded rod (5) at the same time until the spring plunger (9) reaches the end face of the rod body of the single-sided threaded rod (5) and pops out, so that the aluminum alloy hollow tube (7) cannot return, thus achieving one-way locking. Locking in the other direction can be achieved by the baffle of the propeller hub itself.

5. A folding and unfolding bidirectional limiting mechanism for a loitering munition according to claim 1, characterized in that, The rigid flange (10) is connected to the outermost end of the aluminum alloy hollow tube (7) by adhesive or bolt connection.

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