Rotary drive based on adjustable water bubble flexure structure

Abstract

The application relates to a rotary driver based on adjustable water bubble bending structure, which comprises a lower shell, a variable-diameter inner ring structure, a double-layer metal sheet ring and a cover plate. The lower shell is composed of a circular bottom plate and an outer ring structure arranged on the outer peripheral part of the circular bottom plate. The inner ring structure is fixedly connected with the lower shell in a concentric mode. The circumference of the double-layer metal sheet ring is larger than that of the outer ring structure. The double-layer metal sheet ring is arranged between the inner ring structure and the outer ring structure and is partially recessed to form a water bubble bending structure. The outer side surface of the non-recessed part of the double-layer metal sheet ring is attached to the inner side surface of the outer ring structure, and the inner side surface of the recessed part is in contact with the outer side surface of the inner ring structure. The lower part of the cover plate is provided with transmission members and heating sheets on the left and right sides. The transmission members and the heating sheets are in contact with the inner side surface of the double-layer metal sheet ring. The cover plate is arranged on the lower shell and is connected with the lower shell in a concentric rotary mode. An output shaft is arranged on the cover plate. The rotary driver has simple structure, low energy consumption, no need of lubrication and adjustable output torque.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of rotary driver, in particular to a rotary driver based on adjustable water bubble bending structure. BACKGROUND

[0002] In the prior art, the most important form of rotary driver is rotary motor, in which three-phase asynchronous motor has fast rotating speed, high efficiency, good stability and high reliability, so it is most widely used and has large demand. Although some rotary motors have the function of adjusting rotating speed, they cannot guarantee the increase of rotating torque at the same time, so in the special application scenarios such as driving mixer and rotary table, the rotary motor cannot work alone. Single-phase series motor realizes voltage regulation and speed regulation by combining armature winding and field winding, but it needs large voltage, has high requirement for power supply, has relatively complex structure, has relatively high maintenance cost, and still cannot effectively increase torque. At present, the torque is increased by increasing frequency converter, using speed reducer and adjusting voltage and current, which can effectively increase torque, but on the one hand, it increases manufacturing cost and overall size, affects use occasions, and on the other hand, it increases energy consumption and reduces efficiency. Therefore, it is necessary to design a new type of rotary driver to overcome the problems existing in the prior art. SUMMARY

[0003] The present application relates to the field of rotary driver, in particular to a rotary driver based on adjustable water bubble bending structure.

[0004] In order to achieve the above-mentioned purpose, the technical scheme adopted by the present application is: a rotary driver based on adjustable water bubble bending structure, comprising a lower shell, a variable-diameter inner ring structure, a double-layer metal sheet ring and a cover plate, the lower shell is composed of a circular bottom plate and an outer ring structure arranged on the outer peripheral part thereof, the inner ring structure is fixedly connected with the lower shell in a concentric manner, the circumference of the double-layer metal sheet ring is larger than that of the outer ring structure, the double-layer metal sheet ring is arranged between the inner and outer ring structures and partially recessed to form a water bubble bending structure, the outer side surface of the non-recessed part of the double-layer metal sheet ring is attached to the inner side surface of the outer ring structure, and the inner side surface of the recessed part is in contact with the outer side surface of the inner ring structure; the cover plate is provided with a transmission member and a heating sheet on the left and right sides of the lower part thereof, the transmission member and the heating sheet are in contact with the inner side surface of the double-layer metal sheet ring; the cover plate is arranged on the lower shell and connected with the lower shell in a concentric rotating manner, and the output shaft is arranged on the cover plate.

[0005] Further, an arc-shaped sliding groove is formed on the cover plate in the circumferential direction, used for conveniently adjusting the installation position of the two transmission members on the cover plate, and the two transmission members are fixedly installed on the arc-shaped sliding groove through fasteners respectively.

[0006] Further, the transmission member is composed of a vertical rod and a bearing installed on the lower part of the vertical rod, and the upper part of the vertical rod is fixedly connected to the arc-shaped sliding groove of the cover plate through bolts.

[0007] Further, a plurality of support columns for supporting the cover plate are uniformly arranged on the lower part of the cover plate in the circumferential direction, and a bearing is installed on the lower end of each support column, and a ring-shaped groove is formed on the circular bottom plate correspondingly, and the bearings on the lower ends of the support columns are embedded in the ring-shaped groove, so as to realize the concentric rotation of the cover plate relative to the circular bottom plate.

[0008] Further, the inner circular ring structure comprises an inner circular ring support, a plurality of push rods, a rotating disc and a rotating shaft, the inner circular ring support is fixedly connected with the circular bottom plate, a plurality of push rod guide rails are uniformly arranged on the inner circular ring support in the radial direction, the plurality of push rods are embedded on the corresponding push rod guide rails respectively, so as to slide forward and backward in the radial direction, the rotating disc is covered on the circular ring support, a plurality of arc-shaped grooves are formed on the rotating disc, the protrusions on the plurality of push rods are embedded in the corresponding arc-shaped grooves respectively, and the rotating shaft penetrates through the circular bottom plate downward and is rotatably connected with the middle part of the circular bottom plate, and the rotating disc is fixedly connected with the rotating shaft.

[0009] Further, the push rod is a T-shaped structure, which is composed of a sliding rod sliding along the push rod guide rail and an outer push part perpendicularly connected to the front end of the sliding rod, and the outer push part has an arc-shaped surface.

[0010] Further, the inner circular ring support is composed of an upper layer support and a lower layer support, a plurality of upper push rod guide rails are uniformly arranged on the upper layer support in the radial direction upward, a plurality of lower push rod guide rails are uniformly arranged on the lower layer support in the radial direction downward, the lower push rod guide rails are located on the angle bisector of the included angle between the two upper push rod guide rails, and the upper push rod guide rails and the lower push rod guide rails are embedded with corresponding upper push rods and lower push rods respectively, and the inner circular ring structure correspondingly comprises an upper rotating disc and a lower rotating disc, the upper rotating disc is covered on the upper side of the upper layer support, the lower rotating disc is covered on the lower side of the lower layer support, a plurality of arc-shaped grooves are formed on the upper rotating disc and the lower rotating disc respectively, the protrusions on the upper sides of the plurality of upper push rods are embedded in the corresponding arc-shaped grooves of the upper rotating disc respectively, and the protrusions on the lower sides of the plurality of lower push rods are embedded in the corresponding arc-shaped grooves of the lower rotating disc respectively, and the upper rotating disc and the lower rotating disc are fixedly connected with the rotating shaft.

[0011] Further, the expansion coefficient of the inner layer of the double-layer metal sheet ring is higher than that of the outer layer, so that the heating sheet works to heat the double-layer metal sheet ring, the water bubble buckling structure of the double-layer metal sheet ring rolls clockwise / counterclockwise, and the rotating torque is transmitted to the cover plate through the transmission member, the cover plate rotates around the rotating driver center, and the rotating torque is output through the output shaft on the cover plate; the rotating driver can adjust the diameter of the inner ring structure to squeeze the double-layer metal sheet ring to generate water bubble buckling structures of different sizes, so as to adjust the rotating torque of the output shaft.

[0012] Further, the water bubble buckling structure of the double-layer metal sheet ring is determined by the following balance equation set:

[0013] x'(s) = cos θ(s), y'(s) = sin θ(s)

[0014] K θ'' - F x sin θ(s) + F yr cos θ(s) = 0

[0015] K θ'' - F x sin θ(s) + F yl cos θ(s) = 0

[0016] θ(s1) = β, θ(s2) = -β

[0017] where x and y are the Cartesian coordinates of any point on the water bubble buckling configuration, s represents the natural coordinate arc length of any point p on the water bubble buckling configuration, θ(s) represents the angle between the tangent of the water bubble buckling configuration curve at point p and the x-axis, K is the bending stiffness of the double-layer metal sheet ring, F x is the x-direction internal force of the water bubble buckling configuration, F yl and F yr are the y-direction internal forces of the left half and right half of the water bubble buckling configuration, respectively, s1 and s2 are the left and right endpoints of the loading area, respectively, and β is the boundary driving angle at both ends of the loading area.

[0018] In the equilibrium configuration of the loading area, the midpoint deflection of the loading area under different states is obtained; the midpoint deflection is defined as the deflection of the midpoint of the loading area relative to the horizontal axis; when the midpoint deflection of the stable state is equal to the midpoint deflection of the unstable state, the critical boundary driving angle β c can be determined, so that the critical loading curvature κ c is obtained.

[0019]

[0020] where λ is a proportional factor, and s l represents the length of the loading area.

[0021] Further, by changing the diameter of the inner ring structure, the constraint width is adjusted, the decrease of the constraint width and the increase of the loading position can increase the critical load, i.e. the required loading temperature is higher and the generated rotating moment is larger.

[0022] Compared with the prior art, the present application has the following beneficial effects: the present application provides a rotating driver based on an adjustable water bubble buckling structure driving, which adopts the water bubble buckling structure as the driving, the water bubble is locally heated to generate overall rotation, effectively reducing the input energy and reducing the energy consumption; the heating temperature can also control the rotating speed; at the same time, the device also has a variable-diameter inner ring structure, which can quickly change the size of the water bubble to adjust the output torque of the device; in addition, the device has a simple structure, is easy to manufacture, does not need lubrication, is easy to operate, and has low manufacturing cost. Therefore, the present application has strong practicability and broad application prospect. BRIEF DESCRIPTION OF DRAWINGS

[0023] Figure 1 is a structural schematic diagram of the rotating driver of the embodiment of the present application (the cover plate is opened);

[0024] Figure 2 is an exploded view of the structure of the rotating driver of the embodiment of the present application;

[0025] Figure 3 is a force analysis schematic diagram of the water bubble buckling structure in the embodiment of the present application;

[0026] Figure 4 is a jump schematic diagram of the bimetallic strip ring water bubble buckling structure in the embodiment of the present application;

[0027] Figure 5 is a relationship curve diagram between the midpoint deflection and strain energy of the local loading section and the boundary driving angle in the embodiment of the present application;

[0028] Figure 6 is a relationship curve diagram between the different loading positions and the constraint radius and the critical boundary driving angle in the embodiment of the present application. DETAILED DESCRIPTION

[0029] The present application will be further described below in combination with the drawings and embodiments.

[0030] It should be noted that the following detailed description is exemplary and is intended to provide further explanation of the present application. Unless otherwise specified, all technical and scientific terms used herein have the same meaning as generally understood by those skilled in the art to which the present application belongs.

[0031] It is to be understood that the terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting. As used herein, the singular forms "a", "an" and "the" are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms "comprises" and / or "comprising," when used in this specification, specify the presence of stated features, steps, operations, devices, components and / or combinations thereof, but do not preclude the presence or addition of one or more other features, steps, operations, devices, components and / or combinations thereof.

[0032] As shown in Figures 1-2 The present embodiment provides a rotary driver based on adjustable water bubble bending structure, which comprises a lower shell, an inner ring structure with adjustable diameter, a double-layer metal sheet ring 6 and a cover plate 1. The lower shell is composed of a circular bottom plate 16 and an outer ring structure 10 arranged on the outer peripheral part thereof. The inner ring structure is fixedly connected with the lower shell in a concentric manner through a bolt 11. The double-layer metal sheet ring 6 has a circumference greater than that of the outer ring structure. The double-layer metal sheet ring 6 is arranged between the inner and outer ring structures and partially recessed to form a water bubble bending structure. The outer side of the non-recessed part of the double-layer metal sheet ring 6 is attached to the inner side of the outer ring structure 10, while the inner side of the recessed part is in contact with the outer side of the inner ring structure. The cover plate 1 is provided with a transmission member 8 and a heating sheet 13 on the left and right sides of the lower part thereof. The transmission member 8 and the heating sheet 13 are in contact with the inner side of the double-layer metal sheet ring 6. The cover plate 1 is arranged on the lower shell and connected with the lower shell in a concentric manner. An output shaft 18 is arranged on the cover plate 1.

[0033] In order to facilitate the adjustment of the installation position of the transmission member and the heating sheet on the cover plate, an arc-shaped sliding groove 19 is formed on the cover plate 1 in a circumferential direction. Two transmission members 8 are fixedly installed on the arc-shaped sliding groove 19 through fasteners. The cover plate is provided with two heating sheet installation sliding grooves 20 which are symmetrical to each other. Two heating sheets 13 are fixedly installed on the two heating sheet installation sliding grooves 20 through fasteners. In the present embodiment, the transmission member 8 is composed of a vertical rod and a bearing installed on the lower part of the vertical rod. The outer side wall of the bearing is in contact with the inner side of the double-layer metal sheet ring 6. The upper part of the vertical rod is fixedly connected with the arc-shaped sliding groove 19 of the cover plate 1 through a bolt 15. The heating sheet 13 is installed on a heating sheet mounting bracket. The heating sheet mounting bracket is fixedly connected with the sliding groove 20 through a bolt 9 and a nut 14.

[0034] A plurality of support columns 21 for supporting the cover plate are uniformly arranged on the lower part of the cover plate 1 in a circumferential direction. Bearings 2 are installed on the lower ends of the support columns, respectively. An annular groove 17 is formed on the circular bottom plate 16. The bearings 2 at the lower ends of the support columns are embedded in the annular groove 17, so as to realize the concentric rotation of the cover plate 1 relative to the circular bottom plate 16. In the present embodiment, three support columns are arranged.

[0035] The inner circular ring structure comprises an inner circular ring support 5, a plurality of push rods 4, a rotating disc 3 and a rotating shaft 7, the inner circular ring support 5 is fixedly connected with a circular bottom plate 16 through a plurality of bolts 11, a plurality of push rod guide rails 22 are uniformly arranged on the inner circular ring support 5 in the radial direction, the plurality of push rods 4 are respectively embedded on the corresponding push rod guide rails 22 and can slide in the radial direction, the rotating disc 3 is arranged on the inner circular ring support 5, a plurality of arc grooves 23 are formed on the rotating disc 3, and the protrusions on the plurality of push rods 4 are respectively embedded in the corresponding arc grooves 23, the rotating shaft 7 penetrates through the circular bottom plate 16 downwards and is rotatably connected with the middle part of the circular bottom plate 16 through a bearing 12, and the rotating disc 3 is fixedly connected with the rotating shaft 7. The push rod 4 is a T-shaped structure, which is composed of a sliding rod sliding along the push rod guide rail and an outer push part connected to the front end of the sliding rod perpendicularly, and the outer push part has an arc surface.

[0036] In the embodiment, the inner circular ring support 5 is composed of an upper layer support and a lower layer support, a plurality of upper push rod guide rails are uniformly arranged on the upper layer support in the radial direction upwards, a plurality of lower push rod guide rails are uniformly arranged on the lower layer support in the radial direction downwards, the lower push rod guide rails are located on the angle bisector of the included angle between the two upper push rod guide rails, the upper push rod guide rails and the lower push rod guide rails are respectively embedded with corresponding upper push rods 41 and lower push rods 42, and the inner circular ring structure correspondingly comprises an upper rotating disc 3 and a lower rotating disc 24, the upper rotating disc 3 is arranged on the upper side of the upper layer support, the lower rotating disc 24 is arranged on the lower side of the lower layer support, a plurality of arc grooves are respectively formed on the upper rotating disc 3 and the lower rotating disc 24, the protrusions on the upper sides of the plurality of upper push rods are respectively embedded in the corresponding arc grooves of the upper rotating disc, and the protrusions on the lower sides of the plurality of lower push rods are respectively embedded in the corresponding arc grooves of the lower rotating disc; and the upper rotating disc 3 and the lower rotating disc 24 are fixedly connected with the rotating shaft 7. A hexagonal hole is formed in the lower end of the rotating shaft 7, which can be connected with an external driving shaft to drive the rotating shaft 7 to rotate, so as to change the diameter of the inner circular ring structure.

[0037] In the embodiment, the radius R1 of the outer circular ring structure is 67 mm, and the radius R2 of the inner circular ring structure is 33.5-46.5 mm. The temperature curvature of the bimetallic circular ring is 38℃ -1 , the length is 421 mm, and the width is 15 mm.

[0038] The stress condition of the bubble buckling structure is shown in Figure 3 The bubble buckling structure of the double-layer metal sheet circular ring is determined by the following balance equation set:

[0039] x'(s)=cosθ(s), y'(s)=sinθ(s)

[0040] Kθ"-F x sinθ(s)+F yr cosθ(s)=0

[0041] Kθ"-Fx sinθ(s)+F yl cosθ(s)=0

[0042] θ(s1)=β,θ(s2)=-β

[0043] Where x and y are the Cartesian coordinates of any point on the bubble buckling configuration, s represents the natural coordinate arc length of any point p on the bubble buckling configuration, θ(s) represents the angle between the tangent to the bubble buckling configuration curve at point p and the x-axis, the x-axis coincides with the vectors formed by s1 and s2, the y-axis conforms to the right-hand rule, K is the bending stiffness of the double-layer metal ring, and F x It is the internal force in the x-direction of the bubble buckling configuration, F. yl and F yr s1 and s2 are the internal forces in the y direction of the left and right half of the bubble buckling configuration, respectively. s1 and s2 are the left and right endpoints of the loading region, respectively. β is the boundary driving angle at both ends of the loading region.

[0044] In the equilibrium configuration of the loaded region, the midpoint deflection of the loaded region under different states can be obtained. The midpoint deflection is defined as the deflection of the midpoint of the loaded region relative to the horizontal axis, such as... Figure 3 As shown in ω. When the midpoint deflection of steady state 1 is equal to the midpoint deflection of unstable state 1, the critical boundary driving angle β can be determined. c Thus, the critical loading curvature κ can be obtained. c :

[0045]

[0046] Where λ is the scaling factor, s l Indicates the length of the loaded region.

[0047] like Figures 4-5 As shown, the expansion coefficient of the inner layer of the bimetallic ring 6 is higher than that of the outer layer. After the heating element on the right is connected to the power supply, the temperature of the loading area rises, heating the bimetallic ring at the contact position. The boundary driving angle of the loading segment increases, and the deflection at the midpoint of the loading segment first increases and then decreases. At the same time, the strain energy increases. When the midpoint deflection decreases to the same level as the midpoint deflection in the unstable state, the loading segment jumps to the stable state II, and the bubble rotates counterclockwise. Figure 4 As shown, the rotational torque is transmitted to the cover plate 1 via the transmission component 8, thereby outputting a counterclockwise torque through the output shaft on the cover plate 1. After heating the left heating element, the drive outputs a clockwise torque.

[0048] The rotating driver can adjust the rotating torque of the output shaft by adjusting the diameter of the inner ring structure to extrude the double-layer metal sheet ring to generate water bubble buckling structures of different sizes. When adjusting the diameter of the inner ring structure, the mounting positions of the transmission member and the heating sheet on the cover plate are also adjusted accordingly to ensure that the transmission member 8 and the heating sheet 13 are in contact with the double-layer metal sheet ring 6.

[0049] As shown in Figure 6 , the critical boundary driving angle increases with the increase of the loading position and decreases with the increase of the constraint width; the critical boundary driving angle is related to the critical load, the larger the loading position, the larger the critical load, and the larger the constraint width, the smaller the critical load. Therefore, the rotating driver can control the size of the output torque by changing the loading position and the radius of the inner ring structure.

[0050] The above is only a preferred embodiment of the present application, and is not intended to limit the present application in other forms. Any skilled person in the art can modify or change the above disclosed technical content to equivalent embodiments. However, any simple modification, equivalent change and modification of the above embodiments made without departing from the technical solution of the present application, according to the technical essence of the present application, still belongs to the protection scope of the technical solution of the present application.

Claims

1. A rotary actuator based on an adjustable bubble buckling structure, characterized in that, The device includes a lower housing, a variable-diameter inner ring structure, a double-layer metal sheet ring, and a cover plate. The lower housing consists of a circular base plate and an outer ring structure on its outer periphery. The inner ring structure is concentrically fixed to the lower housing. The circumference of the double-layer metal sheet ring is greater than that of the outer ring structure. The double-layer metal sheet ring is positioned between the inner and outer ring structures and is partially concave to form a bubble-like buckling structure. The outer surface of the non-concave portion of the double-layer metal sheet ring is attached to the inner surface of the outer ring structure, while the inner surface of the concave portion contacts the outer surface of the inner ring structure. The cover plate has transmission components and heating elements on its lower left and right sides, both of which contact the inner surface of the double-layer metal sheet ring. The cover plate is mounted on the lower housing and rotatably connected to it concentrically. An output shaft is provided on the cover plate. The inner ring structure includes an inner ring support, multiple push rods, a turntable, and a rotating shaft. The inner ring support is fixedly connected to a circular base plate. Multiple push rod guide rails are evenly distributed radially on the inner ring support, and the multiple push rods are respectively embedded in the corresponding push rod guide rails so as to slide back and forth radially. The turntable is covered on the ring support, and multiple arc-shaped grooves are formed on the turntable. The protrusions on the multiple push rods are respectively embedded in the corresponding arc-shaped grooves. The rotating shaft passes downward through the circular base plate and is rotatably connected to the center of the circular base plate. The turntable is fixedly connected to the rotating shaft. The inner ring support consists of an upper frame and a lower frame. The upper frame has multiple upper push rod guide rails evenly distributed radially upwards, and the lower frame has multiple lower push rod guide rails evenly distributed radially downwards. The lower push rod guide rails are located on the angle bisector of the angle between the two upper push rod guide rails. Corresponding upper push rods and lower push rods are embedded in the upper and lower push rod guide rails, respectively. The inner ring structure includes an upper turntable and a lower turntable. The upper turntable covers the upper side of the upper frame, and the lower turntable covers the lower side of the lower frame. Multiple arc-shaped grooves are opened on the upper and lower turntables, and the protrusions on the upper sides of the multiple upper push rods are respectively embedded in the corresponding arc-shaped grooves of the upper turntable, and the protrusions on the lower sides of the multiple lower push rods are respectively embedded in the corresponding arc-shaped grooves of the lower turntable. Both the upper and lower turntables are fixedly connected to the rotation shaft.

2. The rotary actuator based on an adjustable bubble buckling structure according to claim 1, characterized in that, An arc-shaped groove is formed along the circumference of the cover plate to facilitate the adjustment of the installation position of the two transmission components on the cover plate. The two transmission components are respectively fixedly installed on the arc-shaped groove by fasteners. The cover plate is provided with two symmetrical heating element mounting grooves to facilitate the adjustment of the installation position of the two heating elements on the cover plate. The two heating elements are respectively fixedly installed on the two heating element mounting grooves by fasteners.

3. The rotary actuator based on an adjustable bubble buckling structure according to claim 2, characterized in that, The transmission component consists of a vertical rod and a bearing installed at the lower part of the vertical rod. The upper part of the vertical rod is fixedly connected to the arc-shaped groove of the cover plate by bolts. The heating element is installed on the heating element mounting bracket, and the heating element mounting bracket is fixedly connected to the groove by bolts and nuts.

4. The rotary actuator based on an adjustable bubble buckling structure according to claim 1, characterized in that, The lower part of the cover plate is evenly provided with several pillars for supporting the cover plate along the circumference. Each pillar is equipped with a bearing at its lower end. The circular base plate is provided with an annular groove, and the bearings at the lower ends of each pillar are embedded in the annular groove to achieve concentric rotation of the cover plate relative to the circular base plate.

5. The rotary actuator based on an adjustable bubble buckling structure according to claim 1, characterized in that, The push rod has a T-shaped structure, consisting of a slide rod that slides along the push rod guide rail and an outward push part that is vertically connected to the front end of the slide rod. The outward push part has an arc-shaped surface.

6. The rotary actuator based on an adjustable bubble buckling structure according to claim 1, characterized in that, The inner layer of the double-layer metal sheet ring has a higher coefficient of thermal expansion than the outer layer, which activates the heating element and heats the double-layer metal sheet ring. The bubble buckling structure of the double-layer metal sheet ring rotates clockwise / counterclockwise, and the rotational torque is transmitted to the cover plate through the transmission component. The cover plate rotates around the center of the rotary driver and outputs torque through the output shaft on the cover plate. The rotary driver can adjust the output torque by adjusting the diameter of the inner ring structure to compress the double-layer metal sheet ring to produce bubble buckling structures of different sizes.

7. The rotary actuator based on an adjustable bubble buckling structure according to claim 6, characterized in that, The bubble buckling structure of the double-layered metal sheet annulus is determined by the following set of equilibrium equations: x′(s)=cosθ(s), y′(s)=sinθ(s) Kθ″-F x sinθ(s)+F yr cosθ(s)=0 Kθ″-F x sinθ(s)+F yl cosθ(s)=0 θ(s1)=β,θ(s2)=-β Where x and y are the Cartesian coordinates of any point on the bubble buckling configuration, s represents the natural coordinate arc length of any point p on the bubble buckling configuration, θ(s) represents the angle between the tangent to the bubble buckling configuration curve at point p and the x-axis, K is the bending stiffness of the double-layer metal ring, and F x It is the internal force in the x-direction of the bubble buckling configuration, F. yl and F yr s1 and s2 are the internal forces in the y direction of the left half of the bubble buckling configuration and the right half of the bubble buckling configuration, respectively. s1 and s2 are the left and right endpoints of the loading area, respectively. β is the boundary driving angle at both ends of the loading area. In the equilibrium configuration of the loaded region, the midpoint deflection of the loaded region under different states is obtained; the midpoint deflection is defined as the deflection of the midpoint of the loaded region relative to the horizontal axis; when the midpoint deflection in the stable state is equal to the midpoint deflection in the unstable state, the critical boundary driving angle β can be determined. c Thus, the critical loading curvature κ is obtained. c : Where λ is the scaling factor, s l Indicates the length of the loaded region.

8. The rotary actuator based on an adjustable bubble buckling structure according to claim 6, characterized in that, By changing the diameter of the inner ring structure, the constraint width can be adjusted. Decreasing the constraint width and increasing the loading position can increase the critical load, that is, the required loading temperature is higher and the generated torque is greater.

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