A helical antenna device

Abstract

The present invention provides a helical antenna device, comprising an extension rod, a base, an upper bracket, a flexible support tube, a helical antenna, and a locking device. The extension rod comprises a first connecting tube, a multi-stage retractable and deployable tubular structure, and a second connecting tube, connected sequentially from top to bottom. The multi-stage retractable and deployable tubular structure comprises multiple retractable and deployable tubes, adjacent retractable and deployable tubes being connected via a third connecting tube. The retractable and deployable tubes comprise multiple drive plates, which are arranged in a circle to form the drive tube. The drive plates are made of a shape memory polymer composite material. The extension rod has upper and lower ends connected to the upper bracket and the base, respectively. The flexible support tube is coaxial with the extension rod and has upper and lower ends connected to the upper bracket and the base, respectively. The helical antenna is wound around the flexible support tube. The locking device is used to lock and release the extension rod and the base. The device of the present invention can simultaneously achieve low impact, high controllability, and high reliability during the deployment process, as well as high rigidity after deployment.

Description

Technical Field

[0001] The present invention relates to the technical field of helical antennas, and in particular to a helical antenna device. Background Art

[0002] Helical antennas, characterized by high gain and circularly polarized radiation, are widely used in communications and Earth exploration satellite systems. Low-frequency signals require large antennas, several meters or even more than ten meters long. Because traditional rigid fixed support structures for large helical antennas are too bulky, and the volume of rocket fairings is limited, deployable helical antennas are often used for large spaceborne helical antennas.

[0003] Existing deployable helical antennas typically utilize two designs: an elastic retraction frame and a traditional mechanical retraction and deployment mechanism to achieve retraction and deployment. Deployable helical antennas utilizing an elastic retraction frame experience impacts on the satellite during deployment due to the release of elastic energy, hindering satellite attitude control. Furthermore, the deployment process of the elastic retraction frame exhibits poor controllability and high uncertainty, which can easily lead to localized structural buckling failure and the seizure of moving parts. Traditional mechanical retraction and deployment mechanisms utilize numerous moving pairs, including sliding and rotating pairs. As antenna size increases, the number of moving pairs increases, resulting in a complex overall structure, heavy weight, and low rigidity after deployment. Summary of the Invention

[0004] The technical problem solved by the present invention is that it is difficult for existing deployable helical antennas to simultaneously achieve low impact and high controllability during the deployment process and high rigidity after deployment.

[0005] In order to solve the above technical problems, the technical solution adopted by the present invention is:

[0006] A helical antenna device, comprising:

[0007] The stretching rod comprises a first connecting tube, a multi-stage collapsible and expandable cylindrical structure, and a second connecting tube connected sequentially from top to bottom. The multi-stage collapsible and expandable cylindrical structure comprises a plurality of collapsible and expandable cylinders connected sequentially from top to bottom, with adjacent collapsible and expandable cylinders connected by a third connecting tube. The collapsible and expandable cylinder comprises a plurality of drive plates, which are arranged in a circle to form the drive cylinder. The drive plates are made of a shape memory polymer composite material.

[0008] a base connected to the lower end of the second connecting tube;

[0009] an upper bracket connected to the upper end of the first connecting tube;

[0010] A flexible support tube, the flexible support tube is coaxial with the stretch rod, and the upper and lower ends of the flexible support tube are respectively connected to the upper bracket and the base;

[0011] a helical antenna, the helical antenna being wound around the flexible support tube and fixedly connected thereto;

[0012] A locking device, the lower end of which is fixed to the second connecting cylinder, and the upper end of which is connected to the first connecting cylinder; the locking device is used to lock and release the stretching rod and the base.

[0013] Preferably, connecting plates are respectively provided at the upper and lower ends of the driving plate, and the connecting plates are respectively surrounded by a circle at the upper and lower ends of the driving cylinder to form a fourth connecting cylinder, and the driving cylinder and the fourth connecting cylinders at its upper and lower ends constitute the folding and unfolding cylinder; the connecting plates are respectively rotatably connected to the first connecting cylinder, the second connecting cylinder and the third connecting cylinder.

[0014] Preferably, the plurality of folding and unfolding cylinders include a first folding and unfolding cylinder, and the driving plate inside the first folding and unfolding cylinder is shorter than that of the other folding and unfolding cylinders.

[0015] Preferably, the driving plates are distributed at equal intervals along the circumference of the folding and unfolding cylinder.

[0016] Preferably, the helical antenna device also includes a fourth connecting structure, which is used to fix the third connecting tube and the first connecting tube when the driving tube is retracted, to fix two adjacent third connecting tubes, and to fix the third connecting tube and the second connecting tube. The fourth connecting structure includes grooves and protrusions of matching shapes and sizes.

[0017] Preferably, a heating device is provided in the middle of the driving plate in the length direction.

[0018] Preferably, the heating device is a flexible heating film.

[0019] Preferably, the locking device includes a positioning structure, a locking sleeve, an elastic member, a locking shaft, and a trigger plate. The upper end of the positioning structure is connected to the first connecting cylinder, and the lower end of the positioning structure is provided with a locking hole for inserting the locking shaft. The locking sleeve is provided on the base, and the elastic member is provided between the locking shaft and the locking sleeve. The trigger plate is provided on the base and is made of a shape memory material. The trigger plate can be switched between a high stiffness state and a low stiffness state by heating. When the trigger plate has a high stiffness, the trigger plate can prevent the locking shaft from being withdrawn from the locking hole. When the trigger plate has a low stiffness, the trigger plate cannot prevent the locking shaft from being withdrawn from the locking hole.

[0020] Preferably, the positioning structure includes a positioning rod and a locking buckle, the locking buckle includes a first plate and a second plate, the first plate is vertically connected to the second plate, the upper end of the positioning rod is connected to the first connecting tube, the lower end of the positioning rod is connected to the first plate, and the locking hole is set on the second plate.

[0021] Preferably, the locking device also includes a baffle, the first end of the locking shaft is suitable for inserting into the locking hole, the second end of the locking shaft is connected to the baffle, and the baffle is used to abut against the trigger plate when the driving plate is retracted, thereby restricting the elastic member from popping out the locking shaft.

[0022] Compared to the prior art, the helical antenna device provided by the present invention has an upper end of an extension rod connected to a flexible support tube around which the helical antenna is wound via an upper bracket. The helical antenna can be retracted and extended by retracting the extension rod. The extension rod includes a vertically arranged drive plate made of a shape memory polymer composite material. The helical antenna device can be gradually deployed by heating the drive plate, thereby reducing the impact of the deployment process and improving the controllability of the deployment process. Because the extension rod includes multiple groups of drive plates made of a shape memory polymer composite material from top to bottom, each group of drive plates does not interfere with each other during deployment, thereby increasing reliability. After the helical antenna is deployed, the temperature of the shape memory polymer composite material drops to room temperature. The shape memory polymer composite material has a high modulus at room temperature, providing high stiffness for the extension rod, meeting the stiffness requirements of large helical antenna devices. In summary, the helical antenna device provided by the present invention can simultaneously achieve low impact, high controllability, and high reliability during deployment, as well as high stiffness after deployment, while also having the advantages of a simple structure and a large storage ratio. BRIEF DESCRIPTION OF THE DRAWINGS

[0023] Figure 1 is a schematic diagram of a helical antenna device in a folded state according to an embodiment of the present invention;

[0024] Figure 2 is a schematic diagram of a helical antenna device in an embodiment of the present invention when unfolded;

[0025] Figure 3 A schematic diagram of the helical antenna device in an embodiment of the present invention when deployed, omitting the flexible support tube;

[0026] Figure 4 is a schematic diagram of the stretching rod when it is unfolded in an embodiment of the present invention;

[0027] Figure 5 for Figure 4 Enlarged view of point A in the middle;

[0028] Figure 6 for Figure 4 Enlarged view of point B in the middle;

[0029] Figure 7 for Figure 4 Enlarged view of point C in the middle;

[0030] Figure 8 A schematic diagram of a stretching rod folded in an embodiment of the present invention;

[0031] Figure 9 A schematic diagram of the connection relationship between the various components of the stretch rod in an embodiment of the present invention;

[0032] Figure 10 This is a schematic diagram of an embodiment of the present invention in which the extension rod is retracted without the drive cylinder;

[0033] Figure 11 Schematic diagram of the overall structure of the locking and releasing device in an embodiment of the present invention;

[0034] Figure 12 An exploded view of a locking and releasing device according to an embodiment of the present invention;

[0035] Figure 13 This is a schematic diagram of a locking and releasing device in an embodiment of the present invention in a state where the extension rod is locked;

[0036] Figure 14 is a schematic diagram of the locking and releasing device and the extension rod in an unlocked state according to an embodiment of the present invention;

[0037] Figure 15 Schematic diagram of the connection between the locking release device and the extension rod when the extension rod is locked in an embodiment of the present invention.

[0038] Description of reference numerals:

[0039] 1. Base, 2. Upper bracket, 21. Connecting ring, 22. Horizontal connecting rod, 3. Flexible support tube, 4. Helical antenna, 5. Extension rod, 51. First connecting tube, 511. First lug, 512. Top cover, 52. Second connecting tube, 521. Third lug, 522. Chassis, 53. Third connecting tube, 531. Fourth lug, 54. Drive plate, 55. Connecting plate, 551. Second lug, 6. Locking device, 61. Positioning rod, 62. Locking buckle, 621. Locking hole, 63. Locking sleeve, 64. Locking shaft, 641. Blocking plate, 65. Trigger plate. DETAILED DESCRIPTION

[0040] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, specific embodiments of the present invention are described in detail below with reference to the accompanying drawings.

[0041] It should be noted that the terms "first," "second," and the like in the description and claims of the present invention and the accompanying drawings are used to distinguish similar objects and are not necessarily used to describe a specific order or precedence. It should be understood that the terms used in this manner are interchangeable where appropriate, such that the embodiments of the present invention described herein can be implemented in an order other than that illustrated or described herein.

[0042] like Figure 1-4 As shown, an embodiment of the present invention provides a helical antenna device, comprising:

[0043] The stretching rod 5 includes a first connecting tube 51, a multi-stage folding and unfolding cylindrical structure, and a second connecting tube 52, which are sequentially connected from top to bottom. The multi-stage folding and unfolding cylindrical structure includes multiple folding and unfolding tubes sequentially connected from top to bottom, and adjacent folding and unfolding tubes are connected by a third connecting tube 53. The folding and unfolding tube includes multiple driving plates 54, which are arranged in a circle to form the driving tube, and a first separating opening is defined between adjacent driving plates 54. The driving plates 54 are made of a shape memory polymer composite material.

[0044] Base 1, the base 1 is connected to the lower end of the second connecting tube 52;

[0045] An upper bracket 2 connected to the upper end of the first connecting tube 51;

[0046] A flexible support tube 3, which is sleeved on the stretching rod 5 and coaxial with the stretching rod 5. The upper and lower ends of the flexible support tube 3 are respectively connected to the upper bracket 2 and the base 1. The flexible support tube 3 is made of an elastic material such as silicone and polyimide;

[0047] a helical antenna 4, the helical antenna 4 being wound around the flexible support tube 3 and fixedly connected thereto. For example, the helical antenna 4 is attached to the flexible support tube 3 by gluing or sewing;

[0048] The locking device 6 has its lower end fixed to the second connecting tube 52 and its upper end connected to the first connecting tube 51. This locking device 6 is used to lock and release the extension rod 5 from the base 1. When the extension rod 5 is in the retracted state, the locking device 6 can be used to lock the extension rod 5 to the base 1, which helps to resist vibration loads during rocket launch. When the extension rod 5 is ready to be heated and deployed, the locking device 6 is released.

[0049] The helical antenna device provided by the present invention operates under the following principles: The drive plates 54 on the extension rod 5 are made of a shape-memory polymer composite material. This material exhibits a high modulus at room temperature. When heated to a temperature above its glass transition temperature (Tg), the modulus decreases, allowing it to fold into a V-shape to a collapsed state. This shape is retained even after the temperature is lowered below Tg. When the temperature is raised above Tg, the material returns to its original flat state. Figure 2 This is the state of the helical antenna device in the embodiment of the present invention when it is unfolded. At this time, the extension rod 5 is also in the unfolded state. Figure 4 As shown, when the helical antenna device needs to be folded, the middle portion of the driving plate 54 in the longitudinal direction can be heated to increase the temperature of the portion of the driving plate 54 to above its Tg, so that the driving plate 54 can be folded from the middle to the folded state, so that the stretching rod 5 is folded. The folding of the stretching rod 5 will drive the flexible support tube 3 to shrink, and the shrinking of the flexible support tube 3 will drive the folding of the helical antenna 4. Figure 1 FIG. 1 is a schematic diagram of a helical antenna device folded in an embodiment of the present invention. Figure 8 As shown, when the helical antenna device needs to be unfolded, the middle part of the driving plate 54 in the longitudinal direction is heated to increase the temperature of this part of the driving plate 54 to above its Tg, so that the driving plate 54 is stretched from a folded state to a straight state, so that the stretching rod 5 is unfolded. The unfolding of the stretching rod 5 will drive the flexible support tube 3 to unfold, thereby driving the unfolding of the helical antenna 4.

[0050] Compared to the prior art, the helical antenna device provided by the present invention has an upper end of an extension rod 5 connected to a flexible support tube 3 around which a helical antenna 4 is wound, via an upper bracket 2. The extension rod 5 can be extended and retracted to achieve the retraction and deployment of the helical antenna 4. The extension rod 5 includes a vertically arranged drive plate 54 made of a shape-memory polymer composite material on its body, which can be driven by heat to gradually deploy the helical antenna device, thereby reducing the impact of the deployment process and improving the controllability of the deployment process. Because the extension rod 5 includes multiple groups of drive plates 54 made of a shape-memory polymer composite material from top to bottom, each group of drive plates 54 does not interfere with each other during deployment, thereby increasing the reliability of the deployment process. After the helical antenna device is deployed, the temperature of the shape-memory polymer composite material cools to room temperature. The shape-memory polymer composite material has a high modulus at room temperature, providing the extension rod 5 with high stiffness, meeting the stiffness requirements of large helical antennas. In summary, the helical antenna device provided by the present invention can simultaneously achieve low impact, high controllability, and high reliability during deployment, as well as high stiffness after deployment, while also having the advantages of a simple structure and a large storage ratio. In addition, in the helical antenna device of the present invention, the magnitude of the driving force for the extension rod 5 to unfold can be adjusted in a variety of ways. For example, the driving force for the extension rod 5 to unfold can be adjusted by changing parameters such as the number of groups, length, thickness and cross-sectional central angle of the driving plate 54.

[0051] In the embodiment of the present invention, Figure 4 As shown, the upper and lower ends of the driving piece 54 are respectively provided with connecting pieces 55. The connecting pieces 55 encircle the upper and lower ends of the driving cylinder to form a fourth connecting cylinder. The driving cylinder and the fourth connecting cylinders at its upper and lower ends constitute the folding and unfolding cylinder. A second partition opening is provided between adjacent connecting pieces 55. The connecting pieces 55 are rotatably connected to the first connecting cylinder 51, the second connecting cylinder 52, and the third connecting cylinder 53. In this way, the driving piece 54 can rotate relative to the first connecting cylinder 51, the second connecting cylinder 52, and the third connecting cylinder 53 during the folding and unfolding process, ensuring the coordinated deformation of the driving piece 54 during the folding and unfolding process.

[0052] For example, Figure 4 and Figure 5As shown, the connecting piece 55 is rotatably connected to the first connecting tube 51 via a first connecting structure. The first connecting structure includes a first lug 511, a second lug 551, and a horizontal rotation axis (not shown in the figure). The first lug 511 is disposed on the outer wall of the first connecting tube 51, and the second lug 551 is disposed on the outer wall of the connecting piece 55 and corresponds to the position of the first lug 511. The first lug 511 and the second lug 551 are rotatably connected via the horizontal rotation axis. Specifically, the first lug 511 is provided with a connecting hole, and the second lug 551 is provided with a connecting hole corresponding to the position of the connecting hole on the first lug 511. The connecting holes on the first lug 511 and the second lug 551 are connected via the horizontal rotation axis.

[0053] like Figure 4 and Figure 6 As shown, the connecting piece 55 is rotatably connected to the second connecting tube 52 via a second connecting structure. The second connecting structure includes a third lug 521, a second lug 551, and a horizontal rotation axis (not shown). The third lug 521 is disposed on the outer wall of the second connecting tube 52 and corresponds to the position of the second lug 551 on the outer wall of the connecting piece 55. The third lug 521 and the second lug 551 are rotatably connected via the horizontal rotation axis. Specifically, the third lug 521 is provided with a connection hole corresponding to the position of the connection hole on the second lug 551. The connection hole on the third lug 521 and the connection hole on the second lug 551 are connected via the horizontal rotation axis.

[0054] like Figure 4 and Figure 7 As shown, the connecting piece 55 is rotatably connected to the third connecting tube 53 via a third connecting structure. The third connecting structure includes a fourth lug 531, a second lug 551, and a horizontal rotation axis (not shown). The fourth lug 531 is disposed on the outer wall of the third connecting tube 53 and corresponds to the position of the second lug 551 on the outer wall of the connecting piece 55. The fourth lug 531 and the second lug 551 are rotatably connected via the horizontal rotation axis. Specifically, the fourth lug 531 is provided with a connection hole corresponding to the position of the connection hole on the second lug 551. The connection hole on the fourth lug 531 and the connection hole on the second lug 551 are connected via the horizontal rotation axis.

[0055] like Figure 1 、 Figure 4 and Figure 7 As shown, in the embodiment of the present invention, the lower end of the stretching rod 5 is a second connecting tube 52, the lower end of the second connecting tube 52 is provided with a chassis 522, the chassis 522 is fixedly connected to the base 1, the upper end of the stretching rod 5 is a first connecting tube 51, the upper end of the first connecting tube 51 is connected to a top cover 512, and the upper end of the top cover 512 is fixedly connected to the upper bracket 2. For example, as Figure 1 As shown, the upper bracket 2 includes a connecting ring 21 and three horizontal connecting rods 22. The connecting ring 21 is fixed on the upper end surface of the flexible support tube 3. One end of the horizontal connecting rod 22 is fixedly connected to the inner wall of the connecting ring 21, and the other end is fixedly connected to the top cover 512. The top cover 512 is located in the center of the connecting ring 21, and the three horizontal connecting rods 22 are symmetrically distributed relative to the center line of the connecting ring 21.

[0056] like Figure 4 As shown, in the implementation of the present invention, a multi-stage folding and unfolding cylindrical structure is formed between the first connecting cylinder 51 and the second connecting cylinder 52. The multi-stage folding and unfolding cylindrical structure includes three folding and unfolding cylinders and two third connecting cylinders 53. Each folding and unfolding cylinder includes a plurality of driving plates 54. The plurality of driving plates 54 are enclosed in a circle to form a driving cylinder, and a first partition opening is provided between two adjacent driving plates 54. The upper and lower ends of the driving plates 54 are respectively provided with connecting plates 55. The connecting plates 55 are enclosed in a circle at the upper and lower ends of the driving cylinder to form a fourth connecting cylinder, and a second partition opening driving cylinder and the fourth connecting cylinder connected to the upper and lower ends thereof are provided between two adjacent connecting plates 55 to form the folding and unfolding cylinder. Figure 4 As shown, the three folding and unfolding tubes are respectively a first folding and unfolding tube located relatively at the top, a second folding and unfolding tube located in the middle, and a third folding and unfolding tube located at the bottom; the first folding and unfolding tube is sleeved on the upper outer wall of the third connecting tube 53 located at its lower end; the upper end of the second folding and unfolding tube is sleeved on the lower outer wall of the third connecting tube 53 located at its upper end, and the lower end of the second folding and unfolding tube is sleeved on the upper outer wall of the third connecting tube 53 located at its lower end; the third folding and unfolding tube is sleeved on the lower outer wall of the third connecting tube 53 located at its upper end, forming the folding and unfolding cylindrical structure. The first folding and unfolding tube of the folding and unfolding cylindrical structure is sleeved on the lower outer wall of the first connecting tube 51 located at its upper end, and the third folding and unfolding tube is sleeved on the upper outer wall of the second connecting tube 52 located at its lower end, forming the extension rod 5.

[0057] In this example, Figure 4 As shown, the drive plates 54 on the first, second, and third retracting and unfolding cylinders can be heated separately to achieve retraction and extension of the stretch rod 5. This retracting and unfolding method requires a smaller area to be heated each time and requires less real-time power. Alternatively, the drive plates 54 on the three retracting and unfolding cylinders can be heated simultaneously to achieve retraction and extension of the stretch rod 5.

[0058] like Figure 4As shown, among the first folding and unfolding tube, the second folding and unfolding tube and the third folding and unfolding tube, the driving piece 54 of the first folding and unfolding tube is shorter. During the process of heating and unfolding the stretching rod 5, after the driving pieces 54 on the first folding and unfolding tube and the second folding and unfolding tube are unfolded, the driving piece 54 of the first folding and unfolding tube is heated last. Since the driving piece 54 of the first folding and unfolding tube is shorter, the driving piece 54 can provide a larger unfolding torque in the process of returning from a folded state to a straight state, thereby providing a larger unfolding pre-tightening force for the flexible support tube 3.

[0059] In the embodiment of the present invention, Figure 8-9 As shown, the helical antenna device also includes a fourth connecting structure, which is used to secure the third connecting tube 53 to the first connecting tube 51, secure two adjacent third connecting tubes 53, and secure the third connecting tube 53 to the second connecting tube 52 when the driving tube is retracted. The fourth connecting structure includes grooves and protrusions of matching shapes and sizes. The first connecting tube 51, the third connecting tube 53, and the second connecting tube 52 are mutually constrained by the fourth connecting structure, limiting their respective axial torsional degrees of freedom.

[0060] In an embodiment of the present invention, preferably, the driving plates 54 are distributed at equal intervals along the circumference of the folding and unfolding tube, so that the driving plates 54 and the connecting plates 55 are symmetrically distributed relative to the central axis of the driving tube, so that the stretching rod 5 is subjected to more uniform force during the extension and folding process, making the folding and unfolding process of the helical antenna device more stable.

[0061] To facilitate heating of the drive plate 54, in an embodiment of the present invention, a heating device is provided in the middle of the lengthwise direction of the drive plate 54. Preferably, the heating device is a flexible heating film (not shown). During deformation of the drive plate 54, the flexible heating film can withstand a certain elastic deformation, thereby stably heating the drive plate 54.

[0062] In the embodiment of the present invention, Figure 11-15As shown, the locking device 6 includes a positioning structure, an elastic member (not shown), a locking shaft 64, and a trigger plate 65. The upper end of the positioning structure is connected to the first connecting tube 51, and the lower end of the positioning structure is provided with a locking hole 621 for inserting the locking shaft 64. The locking shaft sleeve 63 is provided on the base 1, and the elastic member is provided between the locking shaft 64 and the locking shaft sleeve 63. The trigger plate 65 is provided on the base 1. The trigger plate 65 is made of shape memory material and has a heating element attached to its surface. Before heating, the material has a high rigidity, which can restrain the elastic member from ejecting the locking shaft 64. After heating, the material has a low rigidity, and the restraining effect on the locking shaft 64 is reduced. Under the action of the elastic member, the locking shaft 64 pushes the trigger plate 65, causing it to become flat and withdraw from the locking hole 621. In an embodiment of the present invention, in the provided helical antenna device, the locking device 6 adopts an axial series locking method, which has a simple locking form and more reliable unlocking. The locking device 6 can control the stiffness of the trigger plate 65 made of shape memory material by changing the temperature thereof to achieve locking and unlocking before the extension rod 5 is driven to unfold.

[0063] For example, in an embodiment of the present invention, the positioning structure includes a positioning rod 61 and a locking buckle 62, and the locking buckle 62 includes a first plate and a second plate, the first plate is vertically connected to the second plate, the upper end of the positioning rod 61 is connected to the first connecting tube 51, and the lower end of the positioning rod 61 is connected to the first plate, and a locking hole 621 is provided on the second plate. Of course, there can be multiple second plates, and when the locking shaft 64 is in the locked state, it passes through the locking holes 621 provided on multiple second plates in sequence, and the locking state of the locking device 6 is more stable. For example, as Figure 11-15 As shown, the locking buckle 62 is a U-shaped locking buckle with an opening downward, the top plate of the U-shaped locking buckle is connected to the positioning rod 61, and locking holes 621 are provided on its two side plates.

[0064] In an embodiment of the present invention, the locking device 6 further includes a locking sleeve 63 and an elastic member. The locking sleeve 63 is disposed on the base 1, and the elastic member is disposed between the locking shaft 64 and the locking sleeve 63. Under the limiting action of the locking sleeve 63, the locking shaft 64 moves more smoothly during insertion and withdrawal from the locking hole 621. By disposing the elastic member between the locking shaft 64 and the locking sleeve 63, the locking shaft 64 can be automatically withdrawn from the locking hole 621. For example, the elastic member can be a compression spring, which is sleeved on the locking shaft 64 and located inside the locking sleeve 63. One end of the compression spring is connected to the locking shaft 64, and the other end is connected to the locking sleeve 63.

[0065] In an embodiment of the present invention, the locking device 6 further includes a blocking piece 641. The first end of the locking shaft 64 is adapted to be inserted into the locking hole 621, and the second end of the locking shaft 64 is connected to the blocking piece 641. The blocking piece 641 is configured to abut against the trigger piece 65 when the driving piece 54 is retracted, thereby restricting the elastic member from ejecting the locking shaft 64. Providing the blocking piece 641 on the locking shaft 64 can make the abutment between the trigger piece 65 and the locking shaft 64 more stable, thereby making the locking state of the locking device 6 more reliable.

[0066] Exemplarily, the locking device 6 includes a positioning rod 61, a locking buckle 62 with a downward U-shaped opening, a locking sleeve 63, a locking shaft 64 and a trigger plate 65. The positioning rod 61 is vertically inserted into the stretching rod 5 and is located at the center of the stretching rod 5. The upper end of the positioning rod 61 passes through the top cover 512 at the upper end of the first connecting tube 51 and is threadedly connected to the top cover 512. The lower end of the positioning rod 61 is connected to the top plate of the locking buckle 62. The side plate of the locking buckle 62 is provided with a locking hole 621. When the stretching rod 5 is in the retracted and locked state, one end of the locking sleeve 63 is sleeved on the locking hole 621 and is coaxial with the locking hole 621. The other end of the locking sleeve 63 passes through the side wall of the second connecting tube 52, and the locking sleeve 63 is threadedly connected to the second connecting tube 52. One end of the locking shaft 64 passes through the locking sleeve 63 and the locking hole 621 in sequence from the outside of the second connecting tube 52. The other end of the locking shaft 64 protrudes from the locking sleeve 63 and is provided with a blocking piece 641. The locking sleeve 63 and the locking shaft 64 are connected by a spring, and the spring is in a compressed state. The trigger piece 65 is arranged on the base 1 and on the route where the locking shaft 64 is pulled out of the locking hole 621.

[0067] For example, in the present invention, the trigger piece 65 is made of a shape-memory polymer composite material. Initially, the trigger piece 65 is flat. When heated above its glass transition temperature (Tg), it is molded into a curved L-shape and retains this shape even after cooling below Tg. When the material temperature is raised above Tg, the trigger piece 65 returns to its initial flat state.

[0068] Exemplarily, the locking mechanism 6 locks the extension rod 5 as follows: When the extension rod 5 is retracted, the locking shaft 64 is pushed into the locking hole 621, compressing the spring between the locking sleeve 63 and the locking shaft 64. An L-shaped trigger plate 65 is then installed, abutting against the retaining plate 641, preventing the locking shaft 64 from being withdrawn from the locking hole 621. At this point, the preload force of the locking mechanism can be adjusted by turning the positioning rod 61 to ensure reliable axial locking between the drive plates 54.

[0069] The unlocking process of the stretching rod 5 is as follows: the trigger plate 65 is heated to a temperature above Tg. At this time, the stiffness of the trigger plate 65 decreases, and the restraining effect on the locking shaft 64 becomes smaller. At this time, the spring elasticity between the locking sleeve 63 and the locking shaft 64 is released, pushing the locking shaft 64 out of the locking hole 621 along the locking sleeve 63, completing the unlocking of the stretching rod 5 before it is driven to be deployed. Subsequently, the deployment of the stretching rod 5 is achieved by heating the driving plate 54 on the stretching rod 5.

[0070] In addition, it should be noted that although the present invention is disclosed as above, the scope of protection disclosed by the present invention is not limited thereto. Those skilled in the art may make various changes and modifications without departing from the spirit and scope of the present invention, and such changes and modifications will fall within the scope of protection of the present invention.

Claims

1. A helical antenna device, characterized in that: include: A stretching rod (5), the stretching rod (5) comprising a first connecting tube (51), a multi-stage folding and unfolding cylindrical structure, and a second connecting tube (52) connected sequentially from top to bottom, the multi-stage folding and unfolding cylindrical structure comprising a plurality of folding and unfolding tubes connected sequentially from top to bottom, adjacent folding and unfolding tubes being connected via a third connecting tube (53); the folding and unfolding tube comprising a plurality of driving plates (54), the plurality of driving plates (54) forming a circle to form a driving tube, and a first separating opening being provided between two adjacent driving plates (54); wherein the manufacturing material of the driving plates (54) comprises a shape memory polymer composite material; A base (1), the base (1) being connected to the lower end of the second connecting tube (52); an upper bracket (2), the upper bracket (2) being connected to the upper end of the first connecting tube (51); A flexible support tube (3), the flexible support tube (3) and the stretching rod (5) are coaxially arranged, and the upper and lower ends are respectively connected to the upper bracket (2) and the base (1); A helical antenna (4), the helical antenna (4) being wound around the flexible support tube (3) and fixedly connected thereto; a locking device (6), wherein the lower end of the locking device (6) is fixed to the second connecting tube (52), and the upper end is connected to the first connecting tube (51); the locking device (6) is used to lock and release the stretching rod (5) and the base (1); The locking device (6) comprises a positioning structure, a locking sleeve (63), an elastic member, a locking shaft (64) and a trigger plate (65); the upper end of the positioning structure is connected to the first connecting tube (51); the lower end of the positioning structure is provided with a locking hole (621) for inserting the locking shaft (64); the locking sleeve (63) is provided on the base (1); the elastic member is provided between the locking shaft (64) and the locking sleeve (63); the trigger plate (65) is provided On the base (1), the trigger piece (65) is made of a shape memory material. The trigger piece (65) can be switched between a state of greater rigidity and a state of less rigidity by heating. When the trigger piece (65) has a greater rigidity, the trigger piece (65) can prevent the locking shaft (64) from being withdrawn from the lock hole (621). When the trigger piece (65) has a smaller rigidity, the trigger piece (65) cannot prevent the locking shaft (64) from being withdrawn from the lock hole (621).

2. The helical antenna device according to claim 1, wherein The upper and lower ends of the driving plate (54) are respectively provided with connecting plates (55), and the connecting plates (55) are respectively formed around the upper and lower ends of the driving cylinder to form a fourth connecting cylinder. The driving cylinder and the fourth connecting cylinders at its upper and lower ends constitute the folding and unfolding cylinder; the connecting plates (55) are respectively rotatably connected to the first connecting cylinder (51), the second connecting cylinder (52) and the third connecting cylinder (53).

3. The helical antenna device according to claim 1, wherein: The plurality of folding and unfolding cylinders include a first folding and unfolding cylinder, and the length of the driving plate (54) inside the first folding and unfolding cylinder is shorter than that of the other folding and unfolding cylinders.

4. The helical antenna device according to claim 1, wherein: The driving plates (54) are distributed at equal intervals along the circumference of the folding and unfolding cylinder.

5. The helical antenna device according to claim 1, wherein: The fourth connecting structure is further included, and the fourth connecting structure is used to fix the third connecting cylinder (53) and the first connecting cylinder (51) when the driving cylinder is retracted, fix two adjacent third connecting cylinders (53), and fix the third connecting cylinder (53) and the second connecting cylinder (52), and the fourth connecting structure includes grooves and protrusions with matching shapes and sizes.

6. The helical antenna device according to claim 1, wherein: A heating device is provided in the middle of the driving piece (54) in the longitudinal direction.

7. The helical antenna device according to claim 6, wherein: The heating device is a flexible heating film.

8. The helical antenna device according to claim 1, wherein: The positioning structure includes a positioning rod (61) and a locking buckle (62), the locking buckle (62) includes a first plate and a second plate, the first plate is vertically connected to the second plate, the upper end of the positioning rod (61) is connected to the first connecting tube (51), the lower end of the positioning rod (61) is connected to the first plate, and the locking hole (621) is provided on the second plate.

9. The helical antenna device according to claim 1, wherein: The locking device (6) further includes a blocking piece (641), a first end of the locking shaft (64) being adapted to be inserted into the locking hole (621), a second end of the locking shaft (64) being connected to the blocking piece (641), and the blocking piece (641) being used to abut against the triggering piece (65) when the driving piece (54) is retracted, thereby restricting the elastic member from ejecting the locking shaft (64).

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