Bidirectional limiting lock

Abstract

The application relates to a bidirectional limiting lock which comprises a shell, a lock tongue, a connecting rod and an unlocking mechanism; the shell is provided with an opening; the lock tongue is rotatably installed in the shell through a first rotating shaft, one end of the lock tongue is an execution end which can extend out of or retract into the opening, and the other end is an abutting end; the connecting rod is rotatably installed in the shell through a second rotating shaft; a first elastic member is arranged between the lock tongue and the shell; when the lock tongue is located at a locking position in which the execution end extends out of the opening, the opposite sides of the abutting end are respectively abutted against the inner wall of the shell and one end of the connecting rod, the lock tongue exerts a force on the connecting rod under the action of the first elastic member, the action line of the force passes through the axis of the second rotating shaft, the connecting rod is located at a mechanical dead point position, and the rotation of the lock tongue is limited; the unlocking mechanism is used for driving the connecting rod to rotate to the dead point position, at this moment, the first elastic member drives the lock tongue to rotate so that the execution end retracts into the opening; compared with the prior art, the bidirectional locking of a single lock tongue can be realized, the structure is simpler, and the weight is lighter.

Description

Technical Field

[0001] This invention relates to the field of lock technology, and specifically to a two-way limit lock. Background Technology

[0002] In drone cargo transport systems, cargo must withstand complex multi-directional inertial forces generated during takeoff, landing, and maneuvers, placing stringent demands on the reliability of cargo restraint locks. Among these, the forward and backward inertial forces along the flight direction are the most significant and are the primary load causing lock failure, necessitating the bidirectional locking capability of the cargo restraint lock. Currently, most common locks employ a unidirectional locking structure, effectively withstanding loads in only one direction. They are prone to failure due to reverse forces, leading to accidental unlocking and safety hazards. To address bidirectional loads, existing technologies employ two independent locking tongues. While this achieves bidirectional locking, it suffers from drawbacks: complex structure, significant weight, and the need for independent actuation of the two tongues, making control coordination difficult and resulting in poor reliability. Therefore, a simple and reliable bidirectional restraint lock is urgently needed to meet the lightweight and high-reliability application requirements of drone cargo transport. Summary of the Invention

[0003] The purpose of this invention is to address the problems of existing UAV cargo movement locks that use two independent locking tongues, which are complex in structure, heavy in weight, and require independent driving of the two locking tongues, making it difficult to guarantee control coordination and resulting in poor reliability. This invention provides a two-way limit lock.

[0004] To achieve the above objectives, the technical solution adopted by the present invention is as follows: A bidirectional limit lock includes a housing, a bolt, a connecting rod, and an unlocking mechanism. The housing has an opening. The bolt is rotatably mounted inside the housing via a first pivot. One end of the bolt is an actuating end that can extend or retract from the opening, and the other end is an abutting end. The connecting rod is rotatably mounted inside the housing via a second pivot. A first elastic element is provided between the bolt and the housing. When the bolt is in the locked position with the actuating end extending from the opening, its opposite sides abut against the inner wall of the housing and one end of the connecting rod, respectively. Under the action of the first elastic element, the bolt applies a force to the connecting rod, and the line of action of the force passes through the axis of the second pivot, causing the connecting rod to be in a mechanical dead position, thereby restricting the rotation of the bolt. The unlocking mechanism is used to drive the connecting rod to rotate so that it is disengaged from the mechanical dead position. When the connecting rod is disengaged from the mechanical dead position, the first elastic element drives the bolt to rotate, causing the actuating end to retract from the opening.

[0005] In this invention, employing the aforementioned technical solution, when the locking tongue's actuating end is in the extended, locked state, both sides of the locking tongue's abutting end will abut against the inner wall of the housing and one end of the connecting rod, respectively. Driven by the first elastic element, the locking tongue applies a force to the connecting rod, and the line of action of this force passes through the axis of the second rotating shaft, thereby stabilizing the connecting rod at its mechanical dead center position. When the locking tongue's actuating end is subjected to a load in a certain direction, the inner wall of the housing blocks the rotation of the locking tongue; when the locking tongue's actuating end is subjected to a load in the opposite direction, the connecting rod blocks the rotation of the locking tongue, thus achieving bidirectional locking of the locking tongue. For unlocking, only the unlocking mechanism needs to drive the connecting rod to rotate. By disengaging one end of the latch from its contact with the locking tongue, the dead-point state is broken, and the locking tongue automatically resets under the action of the first elastic element, causing the actuating end to retract its opening. Compared to the existing technology of drone cargo movement locks that use two independent locking tongues, which are complex in structure, heavy in weight, and require independent driving of the two locking tongues, making it difficult to guarantee control coordination and resulting in poor reliability, this invention uses a single locking tongue in conjunction with a linkage. Through the mechanical dead-point locking design, it achieves a bidirectional locking function of a single locking tongue, which is simpler in structure and lighter in weight, meeting the lightweight requirements of drone cargo transportation. It also eliminates the need for control coordination of two locking tongues, resulting in higher reliability.

[0006] Furthermore, a stop block is provided on the side of the abutting end facing away from the connecting rod. The stop block has a flat surface for abutting against the inner wall of the housing. The stop block with the flat surface increases the contact area between the latch and the inner wall of the housing, making the force on the latch more uniform in the locked state, and improving the structural stability and load-bearing capacity.

[0007] Furthermore, a second elastic element is provided between the connecting rod and the housing. The second elastic element provides an elastic preload force to the connecting rod, keeping its end in contact with the locking tongue abutment end. By providing the second elastic element with a preload force that keeps the connecting rod's end pressed against the locking tongue abutment end, it ensures that during manual locking, as the locking tongue extends out of the opening, the connecting rod can automatically and reliably engage with the locking tongue abutment end and ultimately reach the mechanical dead point position. In addition, the elastic force of the second elastic element can keep the connecting rod tightly against the dead point, preventing loosening due to vibration. The second elastic element can also absorb some impact energy, protecting the connecting rod.

[0008] Furthermore, a sleeve is fixedly provided on the housing, and the second elastic element is a compression spring; one end of the compression spring is housed in the sleeve, and the other end extends out and abuts against the connecting rod to provide the elastic preload; the structure of the sleeve accommodating the compression spring effectively guides and limits the spring, preventing it from deflecting when under force, and ensuring the stability and directional accuracy of the applied elastic preload.

[0009] Furthermore, the unlocking mechanism includes an actuator cylinder installed inside the housing. Its output end is used to abut against and push the connecting rod to rotate, so that one end of the connecting rod disengages from the locking tongue. As a mature and reliable linear drive component, the actuator cylinder can provide stable and precise linear thrust to meet the control requirements of automated unlocking.

[0010] Furthermore, the connecting rod is L-shaped, including a first arm and a second arm, with the second pivot located at the intersection of the first and second arms; the end of the first arm is used to abut against the abutting end of the locking tongue, and the output end of the actuating cylinder is used to abut against and push the second arm; the L-shaped connecting rod design makes its first arm abut against the locking tongue, the second arm acts as the force-bearing arm, and the actuating cylinder acts on the second arm, making the overall structural layout more compact.

[0011] Furthermore, there are two actuators arranged side by side, and the output ends of both actuators act on the connecting rod. The two actuators provide redundancy and backup, so that the other can still work when one actuator fails, which significantly improves the reliability and fault tolerance of the entire lock system.

[0012] Furthermore, the unlocking mechanism includes a manual operation part. An arc-shaped groove is provided on the housing. The manual operation part is a lever fixed to the side of the connecting rod. The lever slides within the arc-shaped groove and partially extends out of the outer wall of the housing. Manual unlocking can be achieved through the cooperation of the lever and the arc-shaped groove. This manual unlocking structure can be provided alone, or an actuating cylinder for unlocking can be provided simultaneously. In this case, automatic unlocking is usually achieved through the actuating cylinder, and manual unlocking is performed in emergency situations such as when the actuating cylinder fails, thus improving the emergency safety and ease of use of the lock.

[0013] Furthermore, the first elastic element is a torsion spring; the torsion spring has a compact structure, is easy to install, and can directly and efficiently apply elastic force to the rotation center of the bolt, providing a stable and reliable power for the automatic reset of the bolt.

[0014] Compared to existing technologies, the advantages of this invention are as follows: It employs a single locking tongue in conjunction with a connecting rod, achieving bidirectional locking functionality through a mechanical dead-point locking design. This results in a simpler structure and lighter weight, meeting the lightweight requirements of UAV cargo transport; it eliminates the need for two locking tongues for control and coordination, leading to higher reliability; it reduces installation space requirements, facilitating placement within the UAV cargo bay; the simplified structure leads to a significant reduction in manufacturing and assembly costs; unlocking is effortless and efficient, requiring only overcoming dead-point friction, resulting in low drive power consumption, low working load on the actuator cylinder, less wear, and extended lifespan; a torsion spring drives the locking tongue to rotate, enabling rapid unlocking and meeting emergency deployment needs; and a second elastic element is provided to provide support for the connecting rod. The preload ensures that the connecting rod is always pressed against the latch abutting end, guaranteeing that during manual locking, as the latch extends out of the opening, the connecting rod automatically and reliably engages with the latch abutting end and ultimately reaches the mechanical dead point. Furthermore, the elastic force of the second elastic element keeps the connecting rod tightly against the dead point, preventing loosening due to vibration. The second elastic element also absorbs some impact energy, protecting the connecting rod. The inclusion of two actuators provides redundancy; if one actuator fails, the other can still operate, significantly improving the reliability and fault tolerance of the entire lock system. Manual unlocking in emergencies such as actuator failure enhances the lock's emergency safety and ease of use. Attached image description: Figure 1 This is a schematic diagram of the structure of the present invention in the locked state; Figure 2 This is a schematic diagram of the structure of the present invention in the unlocked state; Figure 3 This is a cross-sectional view of the invention in the locked state; Figure 4 This is a cross-sectional view of the present invention in the unlocked state; Figure 5 This is a schematic diagram of the structure of the present invention after the housing is removed in the locked state.

[0015] The markings in the diagram are: 1-housing, 2-locking tongue, 3-connecting rod, 4-opening, 5-first rotating shaft, 6-actuating end, 7-abutting end, 8-second rotating shaft, 9-torsion spring, 10-actuating cylinder, 11-stop block, 12-plane, 13-first arm, 14-second arm, 15-compression spring, 16-sleeve, 17-arc groove, 18-pulling block. Detailed Implementation

[0016] The present invention will now be described in detail with reference to the accompanying drawings.

[0017] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are merely illustrative and not intended to limit the invention.

[0018] This embodiment provides a bidirectional limit lock, such as Figures 1-5 As shown, a bidirectional limit lock includes a housing 1, a bolt 2, a connecting rod 3, and an unlocking mechanism. The housing 1 has an opening 4. The bolt 2 is rotatably mounted inside the housing 1 via a first rotating shaft 5. One end of the bolt 2 is an actuating end 6 that can extend or retract from the opening 4, and the other end is an abutting end 7. The first rotating shaft 5 is located between the actuating end 6 and the abutting end 7. The connecting rod 3 is rotatably mounted inside the housing 1 via a second rotating shaft 8. A first elastic element is provided between the bolt 2 and the housing 1. When the bolt 2 is in the locked position where the actuating end 6 extends out of the opening 4, the opposite sides of its abutting end 7 abut against the inner wall of the housing 1 and one end of the connecting rod 3, respectively. The first elastic element applies a force to the connecting rod 3, and the line of action of the force passes through the axis of the second rotating shaft 8, causing the connecting rod 3 to be in a mechanical dead position, thereby restricting the rotation of the locking tongue 2; the unlocking mechanism is used to drive the connecting rod 3 to rotate so that it is removed from the mechanical dead position; when the connecting rod 3 is removed from the mechanical dead position, the first elastic element drives the locking tongue 2 to rotate, causing the actuating end 6 to retract the opening 4; the locking tongue 2 and the connecting rod 3 are both installed between two opposite side walls on the housing 1, the first rotating shaft 5 and the second rotating shaft 8 are parallel to each other and both are perpendicular to the side wall; the first elastic element can be a tension spring, a compression spring or a torsion spring, and in this embodiment, a torsion spring 9 is selected; A stop block 11 is provided on the side of the abutting end 7 facing away from the connecting rod 3. The stop block 11 has a flat surface 12 for abutting against the inner wall of the housing 1. A second elastic element is provided between the connecting rod 3 and the housing 1. The second elastic element is used to provide an elastic preload force to the connecting rod 3 so that its end abuts against the locking tongue 2 abutting end 7. The second elastic element can be a tension spring, a compression spring or a torsion spring. In this embodiment, a sleeve 16 is fixedly provided on the housing 1, and the second elastic element is a compression spring 15; one end of the compression spring 15 is housed in the sleeve 16, and the other end extends out and abuts against the connecting rod 3 to provide elastic preload. The unlocking mechanism includes an actuator 10, which is installed inside the housing 1. Its output end is used to abut against and push the connecting rod 3 to rotate, so that one end of the connecting rod 3 disengages from the abutment of the locking tongue 2. The actuator 10 can be an electromagnetic, hydraulic, electromechanical or other actuators. In this embodiment, an electromechanical actuator is selected. The connecting rod 3 is L-shaped and includes a first arm 13 and a second arm 14. The second rotating shaft 8 is located at the intersection of the first arm 13 and the second arm 14. The end of the first arm 13 is used to abut against the abutting end 7 of the locking tongue 2, and the output end of the actuator 10 is used to abut against and push the second arm 14. There are two actuator cylinders 10, which are arranged side by side, and the output ends of both act on the second arm 14 of the connecting rod 3; there are also two compression springs 15, which are arranged on opposite sides of the second arm 14 in a one-to-one correspondence with the two actuator cylinders 10. The unlocking mechanism also includes a manual operating part. An arc-shaped groove 17 is provided on the housing 1. The manual operating part is a lever 18 fixed to the side of the connecting rod 3. The lever 18 slides within the arc-shaped groove 17 and partially extends out of the outer wall of the housing 1. It should be noted that the unlocking mechanism may also include only the actuating cylinder 10 or only the manual operating part.

[0019] When it is necessary to lock the goods, the locking tongue 2 is driven by a tool or manually to overcome the elastic force of the torsion spring 9, causing it to rotate around the first pivot 5 until the actuating end 6 fully extends out of the opening 4 of the housing 1 and engages with the corresponding lock hole of the goods. During this rotation, the abutting end 7 of the locking tongue 2 eventually reaches a specific position, where its side facing away from the connecting rod 3 is stably abutted against the inner wall of the housing 1 through the plane 12 of the stop block 11, while its side facing the connecting rod 3 abuts against the end of the first arm 13 of the connecting rod 3. At this time, under the restoring force of the torsion spring 9, the locking tongue 2 continuously applies a thrust to the end of the connecting rod 3. Due to the geometry and installation position of the connecting rod 3, the line of action of this thrust passes exactly through the axis of the second pivot 8 of the connecting rod 3. This specific mechanical state makes the driving torque on the connecting rod 3 zero, thus entering the mechanical dead point position. In this position, the connecting rod 3 cannot rotate on its own, firmly restricting the locking tongue 2 in the extended state, forming a stable bidirectional mechanical self-locking mechanism. Regardless of whether the cargo is subjected to forward or backward inertial forces, when these forces are transmitted to the connecting rod 3 and housing 1 through the locking tongue 2, the connecting rod 3 cannot disengage from its dead point, thus achieving reliable bidirectional locking. The elastic preload applied to the connecting rod 3 by the compression spring 15 through the sleeve 16 ensures close contact between the end of the connecting rod 3 and the abutting end 7 of the locking tongue 2, enhancing the stability of the lock.

[0020] When goods need to be released, the unlocking mechanism is activated. In automatic unlocking, the output end of the actuator cylinder 10 extends, abutting against and pushing the second arm 14 of the connecting rod 3, causing the connecting rod 3 to rotate slightly around the second pivot 8. This rotation causes the end of the first arm 13 of the connecting rod 3 to disengage from the contact end 7 of the locking tongue 2, thus breaking the mechanical dead point state. Once the dead point state is broken, the locking tongue 2, driven by the torsion spring 9, immediately rotates in the opposite direction around the first pivot 5, and its actuator end 6 quickly retracts into the opening 4 of the housing 1, completing the unlocking. After unlocking, the output end of the actuator cylinder 10 retracts to avoid obstructing the rotation of the connecting rod 3 during the next locking. In manual unlocking, the operator can directly move the lever 18 extending from the housing, allowing it to slide within the arc-shaped groove 17, which also drives the connecting rod 3 to rotate, achieving the same unlocking effect. The use of two actuator cylinders 10 provides redundancy and ensures unlocking reliability.

[0021] Compared to the existing technology of using two independent locking tongues in UAV cargo restraint locks, which is complex in structure, heavy in weight, and requires independent drive for the two locking tongues, making it difficult to guarantee control coordination and resulting in poor reliability, the present invention uses a single locking tongue in conjunction with a linkage. Through a mechanical dead-point locking design, it achieves bidirectional locking function with a single locking tongue. The structure is simpler and lighter, meeting the lightweight requirements of UAV cargo transport; it eliminates the need for control coordination of two locking tongues, resulting in higher reliability; at the same time, it reduces the installation space requirement, making it easier to arrange in the UAV cargo compartment; the simplified structure leads to a significant reduction in manufacturing and assembly costs; unlocking is labor-saving and efficient, only needing to overcome dead-point friction, resulting in low drive power consumption, small working load on the actuator, less wear, and extended lifespan. A torsion spring drives the bolt to rotate, enabling rapid unlocking and meeting emergency deployment needs. A second elastic element provides a preload force to the connecting rod, ensuring that its end is always pressed against the bolt's contact end. This ensures that during manual locking, as the bolt extends out of the opening, the connecting rod automatically and reliably engages with the bolt's contact end and ultimately reaches its mechanical dead point. Furthermore, the elastic force of the second elastic element keeps the connecting rod tightly against the dead point, preventing loosening due to vibration. The second elastic element also absorbs some impact energy, protecting the connecting rod. Two actuators provide redundancy; if one actuator fails, the other can still operate, significantly improving the reliability and fault tolerance of the entire lock system. Manual unlocking in emergencies such as actuator failure enhances the lock's emergency safety and ease of use.

[0022] The above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present invention should be included within the protection scope of the present invention.

Claims

1. A bidirectional limit lock, characterized in that: The device includes a housing (1), a latch (2), a connecting rod (3), and an unlocking mechanism. The housing (1) has an opening (4). The latch (2) is rotatably mounted inside the housing (1) via a first rotating shaft (5). One end of the latch (2) is an actuating end (6) that can extend or retract from the opening (4), and the other end is an abutting end (7). The connecting rod (3) is rotatably mounted inside the housing (1) via a second rotating shaft (8). A first elastic element is provided between the latch (2) and the housing (1). When the latch (2) is in the locked position where the actuating end (6) extends out of the opening (4), the opposite sides of its abutting end (7) abut against the inner wall of the housing (1) and one end of the connecting rod (3), respectively. Under the action of the first elastic element, the latch (2) applies a force to the connecting rod (3), and the line of action of the force passes through the axis of the second rotating shaft (8), so that the connecting rod (3) is in the mechanical dead point position, thereby restricting the rotation of the latch (2). The unlocking mechanism is used to drive the linkage (3) to rotate so that it is disengaged from the mechanical dead position; when the linkage (3) is disengaged from the mechanical dead position, the first elastic element drives the locking tongue (2) to rotate, so that the actuator (6) retracts the opening (4).

2. The bidirectional limit lock according to claim 1, characterized in that: The abutting end (7) is provided with a stop (11) on the side opposite to the connecting rod (3), and the stop (11) has a plane (12) for abutting against the inner wall of the housing (1).

3. The bidirectional limit lock according to claim 1, characterized in that: A second elastic element is provided between the connecting rod (3) and the housing (1). The second elastic element is used to provide an elastic preload force to the connecting rod (3) to keep its end in contact with the locking tongue (2) abutting end (7).

4. The bidirectional limit lock according to claim 3, characterized in that: A sleeve (16) is fixedly provided on the housing (1), and the second elastic element is a compression spring (15); one end of the compression spring (15) is housed in the sleeve (16), and the other end extends out and abuts against the connecting rod (3) to provide the elastic preload.

5. The bidirectional limit lock according to claim 1, characterized in that: The unlocking mechanism includes an actuator (10), which is installed inside the housing (1). Its output end is used to abut against and push the connecting rod (3) to rotate, so that one end of the connecting rod (3) disengages from the latch (2).

6. The bidirectional limit lock according to claim 5, characterized in that: The connecting rod (3) is L-shaped and includes a first arm (13) and a second arm (14). The second rotating shaft (8) is located at the intersection of the first arm (13) and the second arm (14). The end of the first arm (13) is used to abut against the abutting end (7) of the locking tongue (2), and the output end of the actuating cylinder (10) is used to abut against and push the second arm (14).

7. The bidirectional limit lock according to claim 5, characterized in that: The number of actuators (10) is two, and the two actuators (10) are arranged side by side, and the output ends of both act on the connecting rod (3).

8. The bidirectional limiting lock according to claim 1 or 5, characterized in that: The unlocking mechanism includes a manual operation part. An arc-shaped groove (17) is provided on the housing (1). The manual operation part is a paddle (18) fixed to the side of the connecting rod (3). The paddle (18) is slidably fitted in the arc-shaped groove (17) and partially extends out of the outer wall of the housing (1).

9. The bidirectional limit lock according to claim 1, characterized in that: The first elastic element is a torsion spring (9).

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