Pressing and releasing mechanism driven by shape memory alloy

Abstract

The invention provides a shape memory alloy driven pressing and releasing mechanism, which is characterized in that a separation nut is designed and is used for being in threaded connection with a pressing bolt, and the separation nut is completely separated into four sections; the constraint of the separation nut is arranged on the outer surface and sequentially comprises a plurality of rollers and rollers with grooves in the inner surface, the rollers are separated from the grooves in the pressing state, so that the radial constraint on the separation nut is maintained, and the rollers enter the grooves in the unlocking state, so that the radial constraint on the separation nut is relieved; when the shape memory alloy wire is heated and contracted, the spiral arm is pulled to release the clamping pin, the clamping pin relieves constraint on the rolling wheel, and the rolling wheel rotates under the action of the compression spring to complete unlocking. The pressing and releasing mechanism driven by the shape memory alloy has the advantages of being large in bearing capacity, small in impact, small in size and the like.

Description

Technical Field

[0001] The present invention relates to the technical field of aerospace equipment and devices, and particularly relates to a compression and release mechanism driven by a shape memory alloy. Background Art

[0002] In the aerospace field, the compression and release device is a key component for a spacecraft to withstand mechanical environment impacts and perform space unlocking functions. For example, the separation of a launch vehicle from a payload, the space deployment of large solar panels and other accessories on a satellite, etc. all rely on such a device. However, most of the compression and release devices widely used in current spacecraft are pyrotechnic devices, such as explosive bolts, cutters, and pyrotechnic locks. Although these devices can meet basic requirements, they have many disadvantages. For example, the pyrotechnic impact force is extremely large, usually reaching more than 1000 to 5000g; and most of these devices can only be used once, their reliability is difficult to verify, and there are also problems such as flammability and explosiveness, which make them extremely inconvenient during storage, transportation, and operation.

[0003] Shape memory alloys in the prior art have received more and more attention and applications in the aerospace field due to their unique advantages. Although a variety of compression and release mechanisms driven by shape memory alloys have been successfully developed, such as the Chinese patent application number: 200810119580.0. And another patent document with the patent name of a micro large-load SMA (Shape Memory Alloy) space synchronous unlocking mechanism. Although the "micro large-load SMA space synchronous unlocking mechanism" has many advantages such as a small size, simple structure, high reliability, and fast unlocking speed, it still has some deficiencies:

[0004] 1. Using SMA wires to directly drive the sleeve to move, resulting in limited load-bearing capacity;

[0005] 2. There is sliding friction during the movement of the sleeve, which means that the SMA wires need to overcome a large sliding friction force to drive the sleeve to move. This not only requires a higher stress on the SMA wires but also increases the power of the power supply required to heat the SMA wires accordingly;

[0006] 3. The load direction of the mechanism is the axis direction of the split nut, and when unlocking, there is no direct driving force in the radial direction of the split nut. Therefore, in actual operation, the split nut may not be able to separate smoothly during unlocking, resulting in unlocking failure.

[0007] Based on this, a new solution for a compression and release mechanism driven by a shape memory alloy is needed. Summary of the Invention

[0008] In view of this, an embodiment of this specification provides a rotary large-load and low-impact clamping and releasing mechanism driven by a shape memory alloy, which consists of a double force-increasing mechanism, solves the problems of small load and large friction in the current existing technologies, and provides a large-load, low-impact, and reusable space clamping and releasing mechanism, which can be applied to the clamping and releasing of a space deployable array antenna panel.

[0009] The embodiment of this specification provides the following technical solutions:

[0010] The embodiment of this specification provides a clamping and releasing mechanism driven by a shape memory alloy, including:

[0011] A separating nut, the inner surface of which forms a thread pair with a clamping bolt through threads, and the outer surface of which is in contact with a roller. The roller is used to apply a radial constraint to maintain closure in the clamped state of the separating nut, and release the radial constraint as the roller moves in the unlocked state of the separating nut;

[0012] A roller, the inner surface of which is provided with a groove, and is used to cooperate with the roller to contact and release the radial constraint on the separating nut when unlocking;

[0013] A roller, which is used to disengage from the groove of the roller in the clamped state and apply a radial constraint to the separating nut; in the unlocked state, it enters the groove of the roller to release the radial constraint on the separating nut;

[0014] A cage, which is used to fix the relative position of the roller, ensure the cooperation between the roller and the roller, and automatically reset after unlocking;

[0015] A shape memory alloy wire, one end of which is connected to an electrical interface piece, and the other end is connected to a swing arm through a winding post and a Z-shaped block. When the shape memory alloy wire is energized and shrinks, it is used to pull the swing arm to move through the Z-shaped block and release the constraint on the retaining pin;

[0016] A retaining pin, which is used to be placed in the retaining pin hole of the housing and rotate a preset angle around the axis of the retaining pin to limit the rotation of the roller. In the unlocked state, the movement of the swing arm releases the constraint on the retaining pin, causing the retaining pin to rotate and release the restriction on the roller;

[0017] A swing arm, which is connected to the housing through a torsion spring post, and is used to convert the contraction force of the shape memory alloy wire into a driving force for releasing the constraint on the retaining pin;

[0018] A compression spring, which is connected to the roller, and is used to drive the roller to rotate through the elastic force of the compression spring and provide a driving force when unlocking,

[0019] Push the roller to rotate, so that the roller enters the groove of the roller to complete the unlocking action.

[0020] The present application also provides a pressing and releasing method for a pressing and releasing mechanism driven by a shape memory alloy. Using the pressing and releasing mechanism driven by the shape memory alloy as described in the above technical solution, the method includes the following steps:

[0021] In the pressed state, by tightening the pressing bolt, a thread pair is formed between the separating nut and the pressing bolt, the roller disengages from the groove of the roller, and a radial constraint is applied to the separating nut.

[0022] When unlocking, the shape memory alloy wire is electrified to make it contract and pull the swing arm to move, releasing the constraint on the pin.

[0023] The pin rotates to release the restriction on the roller. The roller rotates under the action of the compression spring, and the roller enters the groove of the roller, releasing the radial constraint on the separating nut.

[0024] The separating nut separates under the action of the separating spring to complete the unlocking action.

[0025] After unlocking is completed, the power supply to the shape memory alloy wire is stopped, and the roller is manually reset. The pin and the swing arm return to the initial position under the action of the compression spring, realizing the reuse of the mechanism.

[0026] Compared with the prior art, the at least one technical solution adopted in the embodiments of the present specification can achieve at least the following beneficial effects:

[0027] The present application adopts a double force-increasing mechanism design, changing sliding friction into rolling friction. The pulling force of the shape memory alloy wire changes from a driving force to a triggering force, with a large load-bearing capacity. Changing the pulling force of the shape memory alloy wire from the unlocking driving force to the unlocking triggering force reduces the wire diameter and actuation stroke of the shape memory alloy wire, and has a low heating power. And the heating time is short, and the unlocking time is fast. It not only has a simple and compact structure, small installation size, and light structural mass. At the same time, a redundant design is adopted, with a high unlocking success rate and improved mechanism reliability. BRIEF DESCRIPTION OF THE DRAWINGS

[0028] In order to more clearly illustrate the technical solutions of the embodiments of the present application, the drawings required to be used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present application. For those of ordinary skill in the art, other drawings can be obtained based on these drawings without creative efforts.

[0029] Figure 1 is a schematic structural diagram of a micro large-load SMA space synchronous unlocking mechanism in the prior art;

[0030] Figure 2 is an axonometric view of a rotary large-load low-impact pressing and releasing mechanism driven by a shape memory alloy in the present application Figure 1 ;

[0031] Figure 3 is the side view of a rotary large-load and low-impact clamping and releasing mechanism driven by a shape memory alloy in the present application Figure 2 ;

[0032] Figure 4 is the front view of a rotary large-load and low-impact clamping and releasing mechanism driven by a shape memory alloy in the present application;

[0033] Figure 5 is the top view of a rotary large-load and low-impact clamping and releasing mechanism driven by a shape memory alloy in the present application;

[0034] Figure 6 is the top view of the hidden upper cover 24 of a rotary large-load and low-impact clamping and releasing mechanism driven by a shape memory alloy in the present application;

[0035] Figure 7 is the explosion diagram of a rotary large-load and low-impact clamping and releasing mechanism driven by a shape memory alloy in the present application Figure 1 ;

[0036] Figure 8 is the explosion diagram of a rotary large-load and low-impact clamping and releasing mechanism driven by a shape memory alloy in the present application Figure 2 ;

[0037] Figure 9 is the explosion diagram of a rotary large-load and low-impact clamping and releasing mechanism driven by a shape memory alloy in the present application Figure 3 .

[0038] Among them, 1. base, 2. antifriction ring, 3. separating nut, 4. nut upper cover, 5. separating spring, 6. roller, 7. cage, 8. roller, 9. cover plate, 10. stop block, 11. electrical interface piece, 12. SMA pressing block, 13. housing, 14. pin, 15. pin pressing block, 16. compression spring, 17. pivot, 18. spring wire, 19. roller column, 20. torsion spring, 21. torsion spring wheel, 22. Z-shaped block, 23. swing arm, 24. upper cover, 25. pressing bolt, 26. shape memory alloy wire, 27. torsion spring column, 28. winding column, 01. upper connecting piece, 02. lower connecting piece, 03. SMA wire, 04. insulating support, 05. end cover, 06. sleeve, 07. resolving nut, 08. bolt, 09. separating top block, 010. insulating pulley, 011. first separating spring, 012. housing, 013. return spring, 014. insulating bearing, 015. support base. Specific embodiments

[0039] The embodiments of the present application will be described in detail below with reference to the accompanying drawings.

[0040] The following describes the implementation manners of the present application through specific specific examples. Those skilled in the art can easily understand other advantages and effects of the present application from the content disclosed in this specification. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. The present application can also be implemented or applied through other different specific implementation manners. Various details in this specification can also be modified or changed based on different viewpoints and applications without departing from the spirit of the present application. It should be noted that, without conflict, the following embodiments and the features in the embodiments can be combined with each other. Based on the embodiments in the present application, all other embodiments obtained by those of ordinary skill in the art without making creative efforts belong to the scope protected by the present application.

[0041] It should be noted that the following describes various aspects of the embodiments within the scope of the appended claims. It should be obvious that the aspects described herein can be embodied in a wide variety of forms, and any specific structure and / or function described herein is illustrative only. Based on the present application, those skilled in the art should understand that one aspect described herein can be implemented independently of any other aspect, and two or more of these aspects can be combined in various ways. For example, any number and aspects described herein can be used to implement the device and / or practice the method. Additionally, this device and / or method can be implemented using other structures and / or functions in addition to one or more of the aspects described herein.

[0042] It should also be noted that the diagrams provided in the following embodiments only illustrate the basic concept of the present application schematically. The diagrams only show the components related to the present application and are not drawn according to the number, shape, and size of the components in actual implementation. The type, quantity, and proportion of each component in its actual implementation can be arbitrarily changed, and the component layout type may also be more complex.

[0043] In addition, in the following description, specific details are provided to facilitate a thorough understanding of the examples. However, those skilled in the art will understand that the examples can be practiced without these specific details.

[0044] Most of the clamping and releasing devices widely used in current spacecraft are pyrotechnic devices, such as explosive bolts, cutters, and pyrotechnic locks. Although these devices can meet the basic requirements, they have many disadvantages. For example, the pyrotechnic impact force is extremely large, usually reaching more than 1000 to 5000g; and most of these devices can only be used once, their reliability is difficult to verify, and there are also problems such as flammability and explosiveness, which makes them extremely inconvenient during storage, transportation, and operation.

[0045] Even when using shape memory alloys, such as using SMA wires as driving elements in the patent document "Miniature Large Load SMA Space Synchronous Unlocking Mechanism", the structure is as follows Figure 1 shown. The unlocking process of this mechanism is as follows: The bottom of the device is connected to the lower connecting piece 02 through the base thread, and the top is connected to the upper connecting piece 01 through the bolt 08. The separation spring 011 and the return spring 013 are both in a pre-compressed state. When unlocking is required, the SMA wire 03 is energized and heated. The SMA wire 03 shrinks and pulls the sleeve 06 downward, and compresses the return spring 013. When the sleeve 06 moves a certain distance and the upper end of the sleeve enters the outer groove of the split nut 07 through the inclined surface, the split nut 07 loses its radial constraint. Under the action of the pre-tightening force and the separation spring 011, it spreads out, and the bolt 08 loses its constraint, thus completing the unlocking. The locking process is as follows: After unlocking is completed, the power supply to the SMA wire 03 is stopped, and the SMA wire 03 cools down and gradually loses its high-temperature recovery force. At this time, the return spring 013 is in a compressed state. When the recovery force of the return spring 013 is greater than the high-temperature recovery force of the SMA wire 03, the return spring 013 gradually stretches the SMA wire 03, and at the same time pushes the sleeve 06 upward. The sleeve gradually locks and closes the split nut 07 through the inclined surface fit between it and the split nut 07 until the pre-release state is reached.

[0046] Although the "Miniature Large Load SMA Space Synchronous Unlocking Mechanism" solution has the advantages of a small mechanism, simple structure, high reliability, fast unlocking speed, etc. Its disadvantages are:

[0047] 1. The SMA wire is directly used to drive the sleeve to move, so the bearing capacity is not large;

[0048] 2. The movement of the sleeve is sliding friction. Therefore, the SMA wire has to overcome the sliding friction force to drive the sleeve to move, which requires a high stress on the SMA wire and also a high power requirement for the power supply heating the SMA.

[0049] 3. The load direction of the mechanism is the axial direction of the split nut. There is no direct driving force in the radial direction of the split nut during unlocking. Therefore, the phenomenon that the split nut does not separate during unlocking may occur, resulting in unlocking failure.

[0050] Based on this, the embodiment of this specification designs a rotary large-load low-impact pressing and releasing mechanism driven by shape memory alloy, designs a split nut, which is used for threaded connection with a pressing bolt and is completely separated into four petals; the constraint of the split nut is set on the outer surface, successively several rollers and a roller with a groove on the inner surface. In the pressed state, the rollers are disengaged from the grooves, thus maintaining the radial constraint on the split nut. In the unlocked state, the rollers enter the grooves, thus releasing the radial constraint on the split nut; a shape memory alloy wire is provided, when it is heated and shrinks, it pulls the swing arm to release the pin, the pin releases the constraint on the roller, and the roller rotates under the action of the compression spring to complete the unlocking. This mechanism has the characteristics of large load-bearing, small impact, small volume, etc.

[0051] The following describes the technical solutions provided by the embodiments of the present application in conjunction with the accompanying drawings.

[0052] One of the technical solutions adopted in the present application is a double-increasing force mechanism. The shape memory alloy wire 26, the Z-shaped block 22, the swing arm 23, and the retaining pin 14 form the first increasing force mechanism; the compression spring 16, the roller 8, the roller 6, and the split nut 3 form the second increasing force mechanism. The first increasing force mechanism converts the normal pressure of the roller 8 on the retaining pin 14 into the sliding friction force between the swing arm 23 and the retaining pin 14. The shape memory alloy wire 26 only needs to overcome this sliding friction force and the restoring force of the spring wire 18 to drive the swing arm 23. The restoring force of the shape memory alloy wire 26 is transformed from the traditional driving force into the triggering force, which is the first increasing force mechanism. The second increasing force mechanism is a bearing-like structure. The roller 8 is equivalent to the outer ring of the bearing, the roller 6 is equivalent to the roller of the bearing, and the split nut 3 is equivalent to the inner ring of the bearing. The present application uses the release of the compression force of the compression spring 16 to push the roller 8 to rotate to complete unlocking. Compared with the traditional pressing and releasing mechanism, the sliding is converted into rolling, reducing the friction coefficient between components and increasing the load-bearing capacity, which is the second increasing force mechanism. The two increasing force mechanisms of the present application make the load of the pressing and releasing mechanism higher than that of the traditional pressing and releasing mechanism.

[0053] As Figures 2 - 9 shown, a shape memory alloy-driven pressing and releasing mechanism of the present application includes:

[0054] The split nut 3, whose inner surface forms a thread pair with the pressing bolt 25 through threads, and whose outer surface is in contact with the roller 6. The roller 6 is used to apply radial restraint to maintain closure in the pressed state of the split nut 3, and release the radial restraint as the roller 6 moves in the unlocked state of the split nut 3;

[0055] The roller 8, whose inner surface is provided with a groove, is used to cooperate with the roller 6 to contact and release the radial restraint on the split nut 3 during unlocking;

[0056] The roller 6 is used to disengage from the groove of the roller 8 in the pressed state and apply radial restraint to the split nut 3; in the unlocked state, it enters the groove of the roller 8 to release the radial restraint on the split nut 3;

[0057] The cage 7 is used to fix the relative position of the roller 6, ensure the cooperation between the roller 6 and the roller 8, and automatically reset after unlocking;

[0058] The shape memory alloy wire 26, one end of which is connected to the electrical interface piece 11, and the other end is connected to the swing arm 23 through the winding post 28 and the Z-shaped block 22. When the shape memory alloy wire 26 is electrified and shrinks, it pulls the swing arm 23 to act through the Z-shaped block 22 to release the restraint on the retaining pin 14;

[0059] The latch pin 14 is used to be placed in the latch pin hole of the housing 13 and rotate a preset angle around the axis of the latch pin, for restricting the rotation of the roller 8. In the unlocked state, the action of the swing arm 23 releases the constraint on the latch pin 14, causing the latch pin 14 to rotate and release the restriction on the roller 8;

[0060] The swing arm 23 is connected to the housing 13 through the torsion spring post 27, and is used to convert the contraction force of the shape memory alloy wire 26 into the driving force for releasing the constraint on the latch pin 14;

[0061] The compression spring 16 is connected to the roller 8, and is used to drive the rotation of the roller through the elastic force of the compression spring 16, and provide the driving force during unlocking,

[0062] Push the roller 8 to rotate, so that the roller pin 6 enters the groove of the roller 8 to complete the unlocking action.

[0063] In some embodiments, as Figure 7 shown, the nut upper cover 4 is in conical surface fit with the upper end surface of the split nut 3, and the split spring 5 is built-in; the split spring 5 is placed in the inner hole of the nut upper cover 4, one end of which acts on the nut upper cover 4, and the other end acts on the inner surface of the housing 13, for restricting the axial constraint when the split nut 3 is pre-tightened and providing the radial driving force during unlocking.

[0064] The lower end surface of the split nut 3 is in fit with the base 1 through an inclined surface, the upper end surface of the split nut 3 is in conical surface fit with a nut upper cover 4, and a pre-compressed split spring 5 is placed in the inner hole of the nut upper cover 4. One end of the split spring 5 acts on the nut upper cover 4, and one end acts on the inner surface of the housing 13, for restricting the axial constraint when the split nut 3 is pre-tightened and providing the radial driving force for the split nut 3 during unlocking, wherein the inclination directions of the inclined surface of the lower end surface and the conical surface of the upper end surface of the split nut 3 are suitable for promoting the separation of the split nut 3.

[0065] In some embodiments, as Figures 7 - 8 shown, it further includes: a pivot 17 and a roller post 19. The roller post 19 is connected to the roller 8 through a thread, and is used to support the roller 8 and transmit the driving force of the compression spring 16; the pivot 17 is used to connect the compression spring 16 and the roller post 19 to ensure the stable action of the compression spring 16; the compression spring 16, one end of which acts on the roller post 19 through the pivot 17, and the other end acts on the housing 13; for providing the driving force during unlocking, pushing the roller 8 to rotate, so that the roller pin 6 enters the groove of the roller 8 to complete the unlocking action.

[0066] In some embodiments, as Figures 7 - 9 , it further includes:

[0067] The latch pin pressing block 15 is used to restrict the position of the latch pin 14 and is fixed on the housing 13 by screws;

[0068] The torsion spring wheel 21 is installed on the torsion spring post 27 and is used to provide the restoring force for the cage 7;

[0069] The torsion spring post 27 is connected to the housing 13 by screws and is used to support the torsion spring wheel 21 and the swing arm 23;

[0070] The spring wire 18 passes through the upper hole of the torsion spring wheel 21 and is fixed to the upper end of the swing arm 23, and is used to provide the holding force for the initial position of the swing arm 23.

[0071] In some embodiments, as Figures 7 - 8 shown, further comprising:

[0072] The cover plate 9 is connected to the cage 7 by a positioning pin and is used to fix the position of the cage 7;

[0073] The stop block 10 is embedded in the groove on the upper surface of the cover plate 9, and the side surface thereof is matched with the side surface of the groove on the upper surface of the housing 13, and is used for positioning the cage 7;

[0074] One end of the torsion spring 20 is inserted into the side hole of the stop block 10 and is wound around the torsion spring wheel 21, and is used to automatically reset the cage 7 after unlocking.

[0075] In some embodiments, as Figures 2 - 9 shown, further comprising:

[0076] The electrical interface piece 11 is used to fix one end of the shape memory alloy wire 26 and is connected to an external power source;

[0077] The SMA pressing block 12 is used to fix the other end of the shape memory alloy wire 26 and is connected to the swing arm 23;

[0078] The wire winding post 28 is used to guide the arrangement of the shape memory alloy wire 26 to ensure that it can effectively pull the swing arm 23 when it contracts when energized.

[0079] In some embodiments, as Figure 7 and Figure 9 shown, further comprising:

[0080] The base 1 is used to support the entire mechanism and is connected to the housing 13 by screws;

[0081] The antifriction ring 2 is placed on the upper surface step of the base 1, and the material thereof is polyimide, and is used to reduce the sliding friction between the roller 8 and the base 1.

[0082] The upper cover 24 is fixed to the housing 13 by screws and is used to protect the internal components and provide structural integrity.

[0083] One of the technical solutions adopted in this application is low-power design. Due to the adoption of a dual force-increasing mechanism, the shape memory alloy wire 26 has changed from the traditional unlocking driving force to an unlocking triggering force, and the required pulling force is greatly reduced. Therefore, compared with the traditional compression release mechanism, the diameter of the shape memory alloy wire 26 of the present invention is small and the actuation displacement is small, thereby reducing the power of the power supply for heating and better adapting to the on-board power supply of the spacecraft.

[0084] One of the technical solutions adopted in this application is redundancy design. To improve the reliability of the mechanism, as Figure 7 shown, two shape memory alloy wires 26 are designed to be symmetrically arranged on the mechanism, and the corresponding retaining pins 14, compression springs 16, roller columns 19, and pivots 17 all adopt redundancy design. When unlocking by energization, as long as one shape memory alloy wire 26 is ensured to pull the swing arm 23, the unlocking can be completed. Similarly, the retaining pins 14, roller columns 19, pivots 17, and compression springs 16 all adopt redundancy design. Compared with the traditional pressure release mechanism, the unlocking success rate is improved.

[0085] In summary, as Figures 2 - 6 shown, for the arrangement method of the shape memory alloy wire 26, one end of the shape memory alloy wire 26 is fixed in the electrical interface piece 11. First, it passes through the upper right hole of the first wire-winding post 28 on the upper surface of the outer shell 13, and bypasses the upper groove on the torsion spring 20 seat, and enters the upper left hole of the second wire-winding post 28 on the opposite side upper surface of the outer shell 13. After turning, it passes through the Z-shaped block 22, and winds back to the lower left row of holes of the second wire-winding post 28, then bypasses the lower groove of the torsion spring 20 seat, and returns to the lower right row of holes of the first wire-winding post 28. Finally, the other end of the shape memory alloy wire 26 is fixed by the electrical interface piece 11 to complete the entry and exit of the entire wire.

[0086] Figure 7 This is the exploded view of the second force-increasing structure of this application. The antifriction ring 2 is placed on the upper end of the base 1. The lower end face of the separating nut 3 is matched with the inclined surface of the base 1. The upper end face of the separating nut 3 is a conical surface and is matched with the nut upper cover 4. A separating spring 4 is built in the nut upper cover 4. The roller 6 is received in the cage 7. The roller 8 is placed on the upper end face of the antifriction ring 2. The cover plate 9 is connected to the cage 7 by a positioning pin. The stop block 10 is received in the inner hole of the cover plate 9. The outer shell 13 is connected to the base 1 by screws. The retaining pin 14 is received in the hole of the retaining pin 14 on the surface of the outer shell 13 and is limited by the retaining pin pressing block 15 and the screw. The SMA pressing block 12 and the electrical interface piece 11 are successively connected to the hole of the lower end of the wire-winding post 28 on the outer shell 13 by screws.

[0087] Figure 8 and 9It is an exploded view of the second force-enhancing mechanism. The torsion spring column 27 is fixed to the square hole at the upper end of the housing 13 by screws. The torsion spring wheel 21 is placed on the upper surface of the torsion spring column 27. The swing arm 23 is sleeved on the torsion spring column 27 through the center hole. The Z-shaped block 22 is fixed to the side of the swing arm 23 by screws. The spring wire 18 passes through the upper end hole of the torsion spring wheel 21 and is fixed to the upper end of the swing arm 23.

[0088] Figure 9 It is an exploded view of the upper cover 24 and the roller column 19. The upper cover 24 is fixed to the upper end of the shell 13 by screws; the roller column 19 is connected to the upper surface of the roller 8 by threads, the pivot 17 is sleeved on the roller column 19 through the pivot 17 hole, one end of the compression spring 16 is sleeved on the pivot 17, and the other end is pressed on the shell 13.

[0089] The working principle of the present application is as follows: the shape memory alloy wire 26 and the compression spring 16 are connected to the SMA pressure block 12 together, and the pressure block constrains the bayonet 14 in the compressed state to prevent the roller 8 from rotating. That is, the housing 13 is connected to the base 1 through screws, and the bayonet 14 is placed in the bayonet hole in the housing 13 and can rotate around the axis of the bayonet 14 by a certain angle. The function of the bayonet 14 is to limit the rotation of the roller 8.

[0090] At this time, the roller 6 contained in the retaining frame 7 is disengaged from the groove on the roller 8, pressing the separation nut 3, making it close together, forming a complete thread pair and cooperating with the clamping bolt 25. By tightening the clamping bolt 25, a pair of pre-tightening forces will be generated between the clamping bolt 25 and the separation nut 3. Since the thread has a certain tooth angle, the pre-tightening force acting on the separation nut 3 is decomposed into axial force and radial force. Finally, the axial force is transmitted to the base 1, and the radial force is transmitted to the roller 6 and the roller 8, and the clamping release device is consolidated with the connected parts. At this time, all forces can be transmitted to the spacecraft structure.

[0091] When released, the shape memory alloy wire 26 is energized and contracts, pulling the bayonet pressing block 15 to rotate around the axial direction of the device, releasing the constraint of the bayonet pressing block 15 on the bayonet 14, and then releasing the constraint of the bayonet 14 on the roller 8. At this time, under the action of the biased separation spring 5, the roller 8 rotates. When the roller 8 rotates to a certain position, the radial constraint on the roller 6 is released, and the roller 6 falls into the groove on the roller 8, releasing the constraint on the separation nut 3. The separation nut 3 is separated under the action of its own radial separation force or the auxiliary structure, and the threaded connection relationship with the clamping bolt 25 is released, and the clamping bolt 25 is released. The SMA wire 26 is de-energized, and the roller 8 is manually rotated to reset it. Then, the bayonet 14 and the SMA pressing block 12 can return to their original positions under the action of the compression spring 16, realizing the reusable function of the clamping release device.

[0092] In combination with the above embodiments, the present application provides a compression and release method of a compression and release mechanism driven by a shape memory alloy, comprising the following steps:

[0093] In the clamped state, by tightening the clamping bolt 25, a screw pair is formed between the separating nut 3 and the clamping bolt 25, the roller 6 disengages from the groove of the roller 8, and a radial constraint is imposed on the separating nut 3;

[0094] When unlocking, the shape memory alloy wire 26 is electrified, causing it to contract and pull the swing arm 23 to move, releasing the constraint on the detent 14;

[0095] The detent 14 rotates, releasing the restriction on the roller 8. The roller 8 rotates under the action of the compression spring 16, and the roller 6 enters the groove of the roller 8, releasing the radial constraint on the separating nut 3;

[0096] The separating nut 3 separates under the action of the separating spring 5, completing the unlocking action;

[0097] After the unlocking is completed, the power supply to the shape memory alloy wire 26 is stopped, and the roller 8 is manually reset. The detent 14 and the swing arm 23 return to their initial positions under the action of the compression spring 16, enabling the reuse of the mechanism.

[0098] Combined with the above embodiments, the present application also provides a space deployable array antenna panel, which is installed on the space deployable array antenna panel by using the shape memory alloy driven clamping and releasing mechanism described in any one of the above technical solutions, and is used for repeatedly deploying or folding the array antenna panel.

[0099] In this specification, the same or similar parts between the various embodiments can be referred to each other. Each embodiment focuses on the differences from other embodiments. In particular, for the embodiments described later, the description is relatively simple, and the relevant parts can be referred to the partial description of the foregoing embodiments.

[0100] The above is only the specific implementation manner of the present application, but the protection scope of the present application is not limited thereto. Any changes or substitutions that can be easily thought of by those skilled in the art within the technical scope disclosed by the present application should be covered by the protection scope of the present application. Therefore, the protection scope of the present application should be subject to the protection scope of the claims.

Claims

1. A compression and release mechanism driven by a shape memory alloy, characterized in that, Comprising: A separating nut, the inner surface of which forms a thread pair with a compression bolt through threads, and the outer surface of which contacts a roller. The roller is used to apply a radial constraint to maintain closure in the state where the separating nut is compressed, and to release the radial constraint following the movement of the roller in the state where the separating nut is unlocked; A roller, the inner surface of which is provided with a groove for cooperating with the roller to contact and release the radial constraint on the separating nut during unlocking; A roller, which is used to disengage from the groove of the roller in the compressed state and apply a radial constraint to the separating nut; in the unlocked state, it enters the groove of the roller to release the radial constraint on the separating nut; A cage for fixing the relative position of the roller, ensuring the cooperation between the roller and the roller, and automatically resetting after unlocking; A shape memory alloy wire, one end of which is connected to an electrical interface piece, and the other end of which is connected to a swing arm through a winding post and a Z-shaped block. When the shape memory alloy wire is energized and shrinks, it is used to pull the swing arm to act through the Z-shaped block to release the constraint on the retaining pin; A retaining pin for being placed in a retaining pin hole of the housing and rotating a preset angle around the axis of the retaining pin to limit the rotation of the roller. In the unlocked state, the action of the swing arm releases the constraint on the retaining pin, causing the retaining pin to rotate and release the limitation on the roller; A swing arm connected to the housing through a torsion spring post, for converting the contraction force of the shape memory alloy wire into a driving force for releasing the constraint on the retaining pin; A compression spring connected to the roller, for driving the roller to rotate through the elastic force of the compression spring and providing a driving force during unlocking, Pushing the roller to rotate, causing the roller to enter the groove of the roller to complete the unlocking action.

2. The shape memory alloy-driven pressing and releasing mechanism according to claim 1, characterized in that Further comprising: A nut upper cover and a separating spring, The nut upper cover, which is in conical surface fit with the upper end surface of the separating nut and has a separating spring built in; The separating spring, which is placed in the inner hole of the nut upper cover, with one end acting on the nut upper cover and the other end acting on the inner surface of the housing, for restricting the axial constraint during the pre-tightening of the separating nut and providing a radial driving force during unlocking.

3. The shape memory alloy-driven pressing and releasing mechanism according to claim 1, wherein Further comprising: A pivot and a roller column, The roller column, which is connected to the roller through threads, for supporting the roller and transmitting the driving force of the compression spring; The pivot for connecting the compression spring and the roller column to ensure the stable action of the compression spring; A compression spring, one end of which acts on the roller column through the pivot and the other end acts on the housing; for providing a driving force during unlocking, pushing the roller to rotate, causing the roller to enter the groove of the roller to complete the unlocking action.

4. The shape memory alloy-driven pressing and releasing mechanism according to claim 1, wherein Further comprising: A retaining pin pressing block for restricting the position of the retaining pin and being fixed to the housing by screws; A torsion spring wheel installed on the torsion spring post for providing a resetting force for the cage; The torsion spring post connected to the housing by screws for supporting the torsion spring wheel and the swing arm; A wire for providing a force for maintaining the initial position of the swing arm.

5. The shape memory alloy-driven pressing and releasing mechanism according to claim 1, wherein Further comprising: A cover plate connected to the cage through a positioning pin for fixing the position of the cage; A stop block embedded in the groove on the upper surface of the cover plate, with the side surface being in fit with the side surface of the groove on the upper surface of the housing for positioning the cage; A torsion spring, with one end inserted into the hole on the side surface of the stop block and wound around the torsion spring wheel, for automatically resetting the cage after unlocking.

6. The shape memory alloy-driven pressing and releasing mechanism according to claim 1, wherein Further comprising: An electrical interface piece for fixing one end of the shape memory alloy wire and connecting to an external power supply; An SMA pressing block for fixing the other end of the shape memory alloy wire and connecting to the swing arm; The wire-winding post is used to guide the arrangement of the shape memory alloy wire to ensure that it pulls the swing arm when it contracts under power.

7. The shape memory alloy-driven pressing and releasing mechanism according to any one of claims 1-6, characterized in that It further includes: The base is used to support the entire mechanism and is connected to the housing by screws; The antifriction ring is placed on the step of the upper surface of the base. The material is polyimide and is used to reduce the sliding friction between the roller and the base.

8. The shape memory alloy-driven low-impact pressing and releasing mechanism according to claim 7, wherein, It further includes: The upper cover is fixed to the housing by screws and is used to protect the internal components and provide structural integrity.

9. A pressing and releasing method of a pressing and releasing mechanism driven by a shape memory alloy, characterized in that, Using the compression-release mechanism driven by the shape memory alloy as described in any one of claims 1 to 8, includes the following steps: In the compressed state, by tightening the compression bolt, the separating nut forms a thread pair with the compression bolt, the roller disengages from the groove of the roller, and a radial constraint is applied to the separating nut; When unlocking, the shape memory alloy wire is energized to make it contract and drive the swing arm to move, releasing the constraint on the latch pin; The latch pin rotates to release the restriction on the roller. The roller rotates under the action of the compression spring, and the roller enters the groove of the roller, releasing the radial constraint on the separating nut; The separating nut separates under the action of the separating spring to complete the unlocking action; After the unlocking is completed, the power supply to the shape memory alloy wire is stopped, and the roller is manually reset. The latch pin and the swing arm return to the initial position under the action of the compression spring to realize the reuse of the mechanism.

10. A space-deployable antenna panel, characterized in that, Including the compression-release mechanism driven by the shape memory alloy as described in any one of claims 1-8 is installed on the space deployable array antenna panel for repeatedly deploying or folding the array antenna panel.

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