Surface self-adaptive anti-deformation actuator

Abstract

This invention relates to the field of hydraulic actuator technology, specifically to a surface-adaptive anti-deformation actuator, comprising an outer cylinder, an inner cylinder, an energy storage assembly, and a piston assembly; the outer cylinder is connected to an oil guide; the inner cylinder is disposed within the outer cylinder; the energy storage assembly is disposed between the outer and inner cylinders; the piston assembly is connected to the energy storage assembly; by vacuum isolating the outer and inner cylinders and recovering cold energy at high altitude, the recovered cold energy is used to pre-cool the hydraulic oil and piston rod when the landing gear opens, enhancing the buffering damping force during landing and braking; and during braking, the connection between the energy storage assembly and the outer cylinder is disconnected, isolating external braking system heat, significantly reducing the temperature change range of the inner cylinder, and preventing thermal deformation; this solves the problem that when the actuator is used on aircraft landing gear, the inner surface of the cylinder will deform due to the rapid temperature change from the low temperature at high altitude to the rapid temperature change during landing and braking, and the excessive instantaneous impact load.

Description

Technical Field

[0001] This invention relates to the field of hydraulic actuator technology, and more specifically to a surface-adaptive anti-deformation actuator. Background Technology

[0002] Hydraulic actuators are devices that use hydraulic energy to generate mechanical motion. They mainly include two categories: hydraulic cylinders and hydraulic motors. They are indispensable power devices in modern industry and engineering, and are currently widely used in heavy machinery, aerospace and shipbuilding.

[0003] When hydraulic actuators are used on aircraft landing gear, the ambient temperature of the actuators during high-altitude cruise can drop below -50°C. During landing and braking, the immense friction and impact loads generate a large amount of heat, causing a rapid rise in the actuator temperature. This drastic temperature change leads to uneven thermal expansion and contraction, generating thermal stress. This causes deformation of the actuator cylinder's inner surface, softening of seals, and a decrease in hydraulic oil viscosity. At this point, the piston rod bears a huge impact load, amplifying even minor deformations between the piston rod and the cylinder's inner surface, potentially leading to permanent deformation and safety hazards. Existing technologies propose methods for cooling hydraulic cylinders, such as patent publication number CN22295. A servo hydraulic cylinder pressure-bearing device (0161U) features a telescopic body at the left end of the piston connecting rod. During the sliding of the piston connecting rod, the telescopic body repeatedly compresses and resets, allowing for high-frequency air exchange within the cylinder chamber. This improves the heat exchange efficiency of the connecting cylinder, reduces the load hazard caused by excessive internal heat, and enhances the practicality of the servo hydraulic cylinder pressure-bearing device. However, for rapid temperature increases caused by massive instantaneous impact loads, where the rate of heat generation far exceeds the air's heat exchange rate, air cannot be pumped out to help dissipate heat from the cylinder. Furthermore, effective support must be provided after the landing gear is deployed. Therefore, it is also necessary to ensure that heat dissipation does not affect the support effect of the actuator itself after the landing gear is deployed.

[0004] In view of the above, in order to overcome the above technical problems, the present invention designs a surface adaptive anti-deformation actuator. Summary of the Invention

[0005] This invention provides a surface-adaptive anti-deformation actuator, which solves the problem of deformation of the inner cylinder surface caused by the rapid temperature change during landing and braking when the actuator is used on aircraft landing gear, and the excessive instantaneous impact load. It utilizes a double-layer cylinder structure with an outer cylinder and an inner cylinder, with a vacuum layer one, an energy storage component, and a vacuum layer two between them. At high altitude, the energy storage component contacts the outer cylinder to accumulate and store cold energy. During landing and braking, as the temperature around the outer cylinder rises, the energy storage component automatically disconnects from the outer cylinder, significantly reducing the transfer of external heat to the inner cylinder. Furthermore, during landing gear opening, the pumping piston slides along with the outer piston rod to draw the energy storage medium into the inner piston rod, pre-cooling the hydraulic oil, increasing the damping force of the landing support, and significantly reducing the peak temperature rise of the inner cylinder under impact load, thereby preventing deformation of the inner cylinder surface.

[0006] To achieve the above objectives, the present invention provides the following technical solution:

[0007] An adaptive anti-deformation actuator includes an oil guide, an outer cylinder, an inner cylinder, an energy storage assembly, and a piston assembly. The outer cylinder is connected to the oil guide. The inner cylinder is disposed within the outer cylinder. The energy storage assembly is disposed between the outer and inner cylinders. When the temperature exceeds a certain limit, the connection between the energy storage assembly and the outer cylinder changes to a disconnected state. When the temperature drops below the limit, the energy storage assembly reconnects to the outer cylinder. The piston assembly is connected to the energy storage assembly. When the piston assembly slides, the energy storage medium in the energy storage assembly is drawn into the piston assembly.

[0008] Preferably, a vacuum layer one is provided between the outer cylinder and the energy storage component; and a vacuum layer two is provided between the energy storage component and the inner cylinder.

[0009] In the above scheme, under high-altitude and low-temperature conditions, the heat transfer between the outer cylinder and the inner cylinder can be greatly reduced through the energy storage component and the vacuum gap, ensuring that the inner cylinder can maintain a normal temperature under high-altitude and low-temperature conditions. Furthermore, during the braking process, the heat generated by external friction can be prevented from being transferred to the inner cylinder, so that the heat for the inner cylinder to heat up comes only from the heat generated during the compression process. In addition, the cold energy will be absorbed by the energy storage component under low-temperature conditions. The vacuum layer can prevent the temperature of the inner cylinder from dropping, thereby reducing the temperature change range of the inner cylinder, preventing large and rapid temperature changes, and thus reducing the generated thermal stress and preventing deformation of the inner surface of the inner cylinder.

[0010] Preferably, the energy storage assembly includes an energy storage cavity, an SMA spring, a conductive bridge plate, a bias spring, and a fixing member; the energy storage cavity is disposed between vacuum layer one and vacuum layer two; the SMA spring is connected to the energy storage cavity; the conductive bridge plate is connected to the SMA spring; the bias spring is connected between the conductive bridge plate and the SMA spring; the fixing member is connected to the energy storage cavity, and the outer ring of the fixing member is connected to the inner wall of the outer cylinder, and the inner ring of the fixing member is connected to the outer wall of the inner cylinder.

[0011] In the above scheme, the outer cylinder will be cooled by the low temperature air at high altitude, and the cold energy will be conducted to the energy storage chamber for accumulation. During the subsequent landing and braking process of the aircraft, the accumulated cold energy can be released for adaptive cooling. The SMA spring can control the contact between the energy conducting bridge plate and the energy storage chamber according to the temperature change.

[0012] Preferably, the cold energy storage medium in the energy storage chamber is a fluorinated liquid; the fixing component is made of PEEK material; the energy conducting bridge is made of a material with high thermal conductivity, and the energy conducting bridge is an arc structure with an inner wall radius equal to the outer wall radius of the energy storage chamber.

[0013] In the above scheme, the fluorinated liquid has a very low freezing point, reaching below -100℃, and good heat transfer performance, maintaining good fluidity even at extremely low temperatures; the fixing component can also ensure good heat insulation while fixing; the energy-conducting bridge plate conducts cold energy through its contact with the energy storage cavity; the energy-conducting bridge plate is an arc-shaped structure with an inner wall radius equal to the outer wall radius of the energy storage cavity, which can improve the contact area and stability, thereby ensuring the conduction efficiency.

[0014] Preferably, the piston assembly includes a piston head, an inner piston rod, an outer piston rod, and a cooling component; the piston head is slidably mounted in the inner cylinder; the inner piston rod is mounted on the central axis of the inner cylinder; the outer piston rod is connected to the piston head and slidably mounted on the inner piston rod; the cooling component is connected between the energy storage chamber and the inner piston rod.

[0015] In the above scheme, the radial force generated by the piston head during the impact will be distributed to both the inner piston rod and the inner cylinder, thereby significantly reducing the radial pressure exerted by the piston head on the inner cylinder and the reaction force on the outer ring of the piston head itself. This prevents deformation of the inner cylinder surface and the outer ring of the piston head, ensuring sealing performance. The sliding extension of the outer piston rod drives the cooling component to draw the energy storage medium into the inner piston rod. At this time, the inner piston rod will transfer the cold energy of the energy storage medium to the hydraulic oil, thereby reducing the temperature of the hydraulic oil for pre-cooling and increasing its viscosity. This allows for the generation of greater damping force during the impact, providing a better buffering and support effect.

[0016] Preferably, the cooling component includes a cooling chamber, a connecting pipe, and a liquid-drawing piston; the cooling chamber is located inside the inner rod of the piston; the connecting pipe connects the inner rod of the piston and the energy storage chamber; the liquid-drawing piston is slidably installed inside the cooling chamber and connected to the outer rod of the piston.

[0017] In the above scheme, the radial force generated by the piston head can be further dispersed by the liquid-drawing piston, which reduces the radial force generated by the piston head on the inner wall of the inner cylinder and the outer surface of the inner piston rod, thereby preventing deformation that would lead to a decrease in sealing performance. During the process of the piston head and the outer piston rod sliding to the extension, the liquid-drawing piston can be driven to slide together. At this time, the liquid-drawing piston will draw the low-temperature energy storage medium that has accumulated cold energy into the cooling chamber, and exchange heat with the hydraulic oil generated during the impact through the cooling chamber. Moreover, this suction process is completed during the opening of the aircraft landing gear, so the hydraulic oil and the inner piston rod can be pre-cooled in advance, avoiding deformation caused by one side of the inner piston rod being low temperature and the other side being high temperature.

[0018] Preferably, the piston inner rod has a liquid inlet channel at its tail end, which is connected to the cooling chamber; the connecting pipe and the head of the liquid-drawing piston are both made of PEEK material, and the tail end of the connecting pipe is installed in the liquid inlet channel.

[0019] In the above scheme, the connecting pipe and the head of the pumping piston are made of heat-insulating material, which can ensure that the cold energy in the energy storage medium inside the connecting pipe will not dissipate at high altitudes, thus ensuring the storage effect of cold energy. At the same time, it can prevent the cold energy from being transferred to the piston rod and hydraulic oil at high altitudes, which would cause the hydraulic oil viscosity to increase and the response speed to slow down during the landing gear opening process.

[0020] Preferably, the inner diameter of the piston head and the inner ring of the piston outer rod is equal to the outer wall diameter of the piston inner rod, and the outer ring edge of the piston head is provided with anti-pressure rounded corners; the liquid-drawing piston has a rod-shaped structure, and the outer ring diameter of the liquid-drawing piston is equal to the inner wall diameter of the cooling chamber.

[0021] In the above scheme, since the inner ring diameter of the piston head and the outer ring diameter of the piston rod are equal to the outer wall diameter of the inner ring diameter of the piston rod, the contact area between the inner and outer ring diameters of the piston rod increases during the impact load process, which significantly reduces the radial pressure and lowers the risk of radial pressure deformation. Furthermore, the anti-pressure fillet can prevent pressure deformation of the contact surface between the piston head and the inner cylinder when a small radial deflection occurs.

[0022] Compared with the prior art, the beneficial effects of the present invention are as follows:

[0023] 1. Compared with existing hydraulic actuators, this invention designs the cylinder body as a double-layer structure of an outer cylinder body and an inner cylinder body, and sequentially sets a vacuum layer one, an energy storage component, and a vacuum layer two between the outer cylinder body and the inner cylinder body. This prevents the temperature of the inner cylinder body from changing drastically due to external heat during high-altitude low-temperature environments and braking processes, thus reducing the temperature variation range of the inner cylinder body, reducing thermal stress, and preventing deformation of the inner surface of the inner cylinder body. In high-altitude low-temperature environments, the energy storage component will accumulate and recover cold energy. During the subsequent descent and braking process, the recovered cold energy is used to pre-cool the hydraulic oil and piston rod, thereby reducing the temperature rise peak when subjected to huge instantaneous impacts, limiting the diffusion of heat to the inner wall of the inner cylinder body, and thus preventing sealing leaks caused by deformation of the inner cylinder body and piston rod.

[0024] 2. This invention, by setting up a liquid-drawing piston, allows the outer piston rod to slide out and drive the liquid-drawing piston to draw the energy storage medium from the energy storage chamber into the inner piston rod during the aircraft landing gear opening process. At this time, the inner piston rod will transfer the cold energy of the energy storage medium to the hydraulic oil, thereby reducing the temperature of the hydraulic oil for pre-cooling and increasing its viscosity. This allows for the generation of greater damping force during impact, providing a better buffering and support effect. Since it is used on aircraft landing gear, which is not a scenario where the hydraulic oil needs to circulate, but only needs to protect the aircraft body in a one-time extreme impact, pre-cooling will not affect the working response efficiency and can effectively reduce the peak temperature of the hydraulic oil. Furthermore, the pre-cooling process is completed during the aircraft landing gear opening process, so it can pre-cool the hydraulic oil and the inner piston rod in advance, avoiding deformation caused by one side of the inner piston rod being low temperature and the other side being high temperature, thus ensuring sealing performance.

[0025] 3. This invention, through the inner cylinder, piston head, piston outer rod, piston inner rod, and liquid-drawing piston, disperses the radial force generated during the impact process to the inner cylinder and piston inner rod via the piston head, piston outer rod, and liquid-drawing piston. This significantly reduces the radial pressure exerted by the piston head on the inner cylinder and the reaction force on the outer ring of the piston head itself, thereby preventing deformation of the inner cylinder surface and the outer ring of the piston head, ensuring sealing performance. The piston outer rod and piston inner rod have a longer sleeve section, resulting in a larger contact area, which significantly reduces radial pressure and lowers the risk of radial deformation. Attached Figure Description

[0026] To more clearly illustrate the specific embodiments of the present invention or the technical solutions in the prior art, the drawings used in the description of the specific embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are some embodiments of the present invention. For those skilled in the art, other drawings can be obtained from these drawings without creative effort.

[0027] Figure 1This is an overall structural diagram of the present invention;

[0028] Figure 2 This is a schematic diagram of the internal structure of the present invention;

[0029] Figure 3 This is a cross-sectional view of the present invention;

[0030] Figure 4 for Figure 3 Enlarged view of the structure at point A in the middle;

[0031] Figure 5 for Figure 3 Enlarged view of the structure at point B in the middle;

[0032] Figure 6 This is a diagram illustrating the cold energy recovery process under high-altitude, low-temperature conditions according to the present invention.

[0033] Figure 7 This is a state diagram of the piston assembly and energy storage assembly when the landing gear of an aircraft is deployed during landing braking, according to the present invention.

[0034] Figure 8 for Figure 7 Enlarged view of the structure at point C.

[0035] In the diagram: 1. Oil guide component; 2. Outer cylinder; 3. Inner cylinder; 4. Energy storage assembly; 41. Energy storage chamber; 42. SMA spring; 43. Energy guide bridge; 44. Offset spring; 45. Fixing component; 5. Piston assembly; 51. Piston head; 511. Anti-pressure fillet; 52. Inner piston rod; 521. Liquid inlet channel; 53. Outer piston rod; 54. Cooling component; 541. Cooling chamber; 542. Connecting pipe; 543. Liquid extraction piston; 6. Vacuum layer one; 7. Vacuum layer two. Detailed Implementation

[0036] To better understand the above technical solutions, the following will provide a detailed explanation of the technical solutions in conjunction with the accompanying drawings and specific implementation methods.

[0037] Please see Figures 1 to 8 This invention provides a surface-adaptive anti-deformation actuator, the technical solution of which is as follows:

[0038] As a specific embodiment of the present invention, refer to Figure 1 and Figure 2An adaptive anti-deformation actuator is disclosed. It includes an oil guide 1, the pipes of which are all made of heat-insulating material. It also includes an outer cylinder 2, an inner cylinder 3, an energy storage assembly 4, and a piston assembly 5. The outer cylinder 2 is connected to the oil guide 1. The inner cylinder 3 is disposed inside the outer cylinder 2. The energy storage assembly 4 is disposed between the outer cylinder 2 and the inner cylinder 3. When the temperature exceeds a certain limit (here, the limit is 25°C), the connection between the energy storage assembly 4 and the outer cylinder 2 changes from connected to disconnected. When the temperature drops below the limit (here, the limit is 25°C), the energy storage assembly 4 reconnects to the outer cylinder 2. The piston assembly 5 is connected to the energy storage assembly 4. When the piston assembly 5 slides, it draws the energy storage medium from the energy storage assembly 4 into the piston assembly 5.

[0039] As a specific embodiment of the present invention, refer to Figure 2 and Figure 3 A vacuum layer 6 is provided between the outer cylinder 2 and the energy storage component 4; a vacuum layer 7 is provided between the energy storage component 4 and the inner cylinder 3. In high-altitude, low-temperature environments, the energy storage component 4 and the vacuum layer 7 significantly reduce heat transfer between the outer cylinder 2 and the inner cylinder 3, ensuring that the inner cylinder 3 maintains a normal temperature under these conditions. Furthermore, during braking, heat generated by external friction is prevented from being transferred to the inner cylinder 3, ensuring that the heat generated during compression is solely due to the heat generated during the compression process. In low-temperature environments, cold energy is absorbed by the energy storage component 4. The vacuum layer 7 prevents the temperature of the inner cylinder 3 from dropping, thereby reducing the temperature variation range and preventing drastic temperature changes. This reduces thermal stress and prevents deformation of the inner surface of the inner cylinder 3. Vacuum layers 6 and 7 are permanently sealed using electron beam deep-penetration welding during manufacturing, and the evacuation port is sealed after vacuuming. A non-evaporable getter film is applied to the wall surface to maintain long-term high vacuum conditions.

[0040] As a specific embodiment of the present invention, refer to Figure 3 , Figure 4 and Figure 8The energy storage assembly 4 includes an energy storage chamber 41, an SMA spring 42, an energy-conducting bridge plate 43, an offset spring 44, and a fixing member 45. The energy storage chamber 41 is disposed between vacuum layer 6 and vacuum layer 7, and the energy storage chamber 41 is made of a material that facilitates the conduction of cold energy. The SMA spring 42 is connected to the energy storage chamber 41. The energy-conducting bridge plate 43 is connected to the SMA spring 42. The offset spring 44 is connected between the energy-conducting bridge plate 43 and the SMA spring 42. The fixing member 45 is connected to the energy storage chamber 41, and the outer ring of the fixing member 45 is connected to the inner wall of the outer cylinder 2, and the inner ring of the fixing member 45 is connected to the outer wall of the inner cylinder 3. At high altitude, the outer cylinder 2 cools the low-temperature air from the outside, and the cold energy is conducted to the energy storage medium in the energy storage chamber 41 for accumulation. During the subsequent landing and braking process, the accumulated cold energy can be released for adaptive cooling. The SMA spring 42 can control the contact between the energy conducting bridge plate 43 and the energy storage chamber 41 according to the temperature change. The phase transition temperature of the SMA spring 42 can be set to about 25°C. When the temperature rises above 25°C, the SMA spring 42 returns to its memory shape under the unidirectional memory effect. At this time, the SMA spring 42 will overcome the elastic force of the bias spring 44 (that is, the total elastic force generated by the SMA spring 42 when returning to its memory shape is greater than the total elastic force of the bias spring 44), and pull the energy conducting bridge plate 43 in the radial direction of the outer cylinder 2 until it is separated from the energy storage chamber 41, thereby disconnecting the heat. The heat transfer prevents the heat from the outer cylinder 2 from being transferred to the energy storage chamber 41, ensuring that the energy storage medium in the energy storage chamber 41 remains at a low temperature (cold energy accumulated from the high altitude). When the temperature drops below 25°C, the SMA spring 42 softens again (returns to the martensitic state). At this time, under the biasing force of the bias spring 44, the SMA spring 42 returns to its original elongated state, and the energy conduction bridge plate 43 contacts the energy storage chamber 41 again. Here, the SMA spring 42 is made of nickel-titanium alloy, and the phase change temperature is controlled at around 25°C, which allows the heat transfer to be quickly disconnected when the temperature rises. Furthermore, since the SMA spring 42 is directly connected to the outer cylinder 2, the contact is disconnected before the heat is transferred to the energy storage chamber 41 when the temperature rises rapidly, thus ensuring the low temperature state inside the energy storage chamber 41.

[0041] As a specific embodiment of the present invention, refer to Figure 4 and Figure 8The cold energy storage medium in the energy storage chamber 41 is a fluorinated liquid; the fixing component 45 is made of PEEK material; the energy-conducting bridge plate 43 is made of a material with high thermal conductivity, and the energy-conducting bridge plate 43 is an arc-shaped structure with an inner wall radius equal to the outer wall radius of the energy storage chamber 41. The fluorinated liquid has a very low freezing point, reaching below -100℃, and has good heat transfer performance, maintaining good fluidity even at extremely low temperatures; the fixing component 45 ensures good heat insulation while fixing the energy storage chamber 41; the energy-conducting bridge plate 43 conducts cold energy through its contact with the energy storage chamber 41, and the arc-shaped structure with an inner wall radius equal to the outer wall radius of the energy storage chamber 41 improves the contact area and stability, thereby ensuring conduction efficiency.

[0042] As a specific embodiment of the present invention, refer to Figure 5 , Figure 6 and Figure 7 The piston assembly 5 includes a piston head 51, an inner piston rod 52, an outer piston rod 53, and a cooling component 54; the piston head 51 is slidably mounted inside the inner cylinder 3; the inner piston rod 52 is mounted on the central axis of the inner cylinder 3; the outer piston rod 53 is connected to the piston head 51 and slidably mounted on the inner piston rod 52; the cooling component 54 is connected between the energy storage chamber 41 and the inner piston rod 52. The radial force generated by the piston head 51 during the impact process will be distributed to both the inner piston rod 52 and the inner cylinder 3, thereby significantly reducing the radial pressure exerted by the piston head 51 on the inner cylinder 3 and the reaction force on the outer ring of the piston head 51 itself. This prevents deformation of the surface of the inner cylinder 3 and the outer ring of the piston head 51, ensuring sealing performance. The sliding extension of the outer piston rod 53 drives the cooling component 54 to draw the energy storage medium into the inner piston rod 52. At this time, the inner piston rod 52 will transfer the cold energy of the energy storage medium to the hydraulic oil, thereby reducing the temperature of the hydraulic oil for pre-cooling and increasing its viscosity (and due to the landing gear opening time...). The pre-cooling process is relatively short, so it will not reduce the temperature of the hydraulic oil and piston inner rod 52 too much, thus ensuring that there will not be a large temperature difference during the subsequent heat absorption process. This allows for the generation of greater damping force during impact, providing a better buffering and support effect. Since it is used on aircraft landing gear, which is not a scenario where the hydraulic oil needs to circulate, it only needs to protect the aircraft body in a one-time extreme impact. Therefore, pre-cooling will not affect the working response efficiency. It can also reduce the peak temperature rise caused by the heat generated by the hydraulic oil when it is impacted, and at the same time limit the heat diffusion to the inner wall of the inner cylinder 3.

[0043] As a specific embodiment of the present invention, refer to Figure 5 , Figure 6 and Figure 7The cooling component 54 includes a cooling chamber 541, a connecting pipe 542, and a liquid-drawing piston 543. The cooling chamber 541 is located inside the inner piston rod 52. The connecting pipe 542 connects the inner piston rod 52 and the energy storage chamber 41. The liquid-drawing piston 543 is slidably installed inside the cooling chamber 541 and connected to the outer piston rod 53. The liquid-drawing piston 543 further disperses the radial force generated by the piston head 51, reducing the radial force exerted by the piston head 51 on the inner wall of the inner cylinder 3 and the outer surface of the inner piston rod 52, thus preventing deformation and a decrease in sealing performance. During the sliding process of the piston head 51 and the outer piston rod 53 to their extended positions, the liquid-drawing piston 543 slides along with it. At this time, the liquid-drawing piston 543 draws the low-temperature energy storage medium, which has accumulated cold energy, into the cooling chamber 541, where it exchanges heat with the hydraulic oil generated during the impact process. The suction process is completed during the opening of the aircraft landing gear, so the hydraulic oil and piston inner rod 52 can be pre-cooled in advance to avoid deformation caused by one side of the piston inner rod 52 being low temperature and the other side being high temperature. Since the entire actuator will become vertical when the aircraft landing gear is opened, the energy storage medium sucked into the cooling chamber 541 can remain in the cooling chamber 541 under the action of gravity. When the aircraft landing gear is retracted, the piston outer rod 53 will return to the retracted state and press the pumping piston 543 again to press the energy storage medium back into the energy storage chamber 41.

[0044] As a specific embodiment of the present invention, refer to Figure 5 , Figure 6 and Figure 7 The piston inner rod 52 has a liquid inlet channel 521 at its tail, which communicates with the cooling chamber 541. The connecting pipe 542 and the head of the liquid-drawing piston 543 are both made of PEEK material, and the tail of the connecting pipe 542 is installed inside the liquid inlet channel 521. The connecting pipe 542 and the head of the liquid-drawing piston 543 are made of heat-insulating material, which can ensure that the cold energy in the energy storage medium inside the connecting pipe 542 will not dissipate at high altitudes, thus ensuring the storage effect of cold energy. At the same time, it can prevent the cold energy from being transferred to the piston inner rod 52 and hydraulic oil at high altitudes, which would cause the hydraulic oil viscosity to increase and the response speed to slow down during the landing gear opening process.

[0045] As a specific embodiment of the present invention, refer to Figure 6 and Figure 7The inner diameters of the piston head 51 and the outer piston rod 53 are equal to the outer wall diameter of the inner piston rod 52, and the outer edge of the piston head 51 is provided with an anti-pressure fillet 511. The liquid-drawing piston 543 has a rod-shaped structure, and the outer diameter of the liquid-drawing piston 543 is equal to the inner wall diameter of the cooling chamber 541. Since the inner diameters of the piston head 51 and the outer piston rod 53 are equal to the outer wall diameter of the inner piston rod 52, the contact area between the inner piston rod 52 and the outer piston rod 53 can be increased during the process of bearing impact loads, which significantly reduces the radial pressure and reduces the risk of radial pressure deformation. Furthermore, the anti-pressure fillet 511 can prevent pressure deformation of the contact surface between the piston head 51 and the inner cylinder 3 when a small radial deflection occurs.

[0046] Work process: When the aircraft landing gear is retracted, the outer piston rod 53 retracts into the inner cylinder 3. At this time, the liquid pumping piston 543 blocks the liquid inlet channel 521, preventing the energy storage medium from entering the cooling chamber 541. During the high-altitude flight of the aircraft, the ambient temperature will drop below -50℃. At this time, the ambient cold energy will be transferred to the outer cylinder 2, and the cold energy can be transferred to the energy conducting bridge plate 43 through the outer cylinder 2. Then, the energy conducting bridge plate 43 transfers the cold energy to the energy storage medium in the energy storage chamber 41 for cold energy accumulation.

[0047] Before the aircraft lands, the landing gear will open first. At this time, the outer piston rod 53 will slide out and drive the liquid pumping piston 543 to slide together. The liquid pumping piston 543 slides to draw the low temperature energy storage medium in the energy storage chamber 41 into the cooling chamber 541, pre-cooling the hydraulic oil and the inner piston rod 52 in advance.

[0048] During the landing and braking process, the braking system generates enormous heat due to friction, causing the ambient temperature of the entire actuator to rise rapidly. The outer cylinder 2, subjected to this heat, will also heat up quickly. When the temperature reaches above 25°C, the SMA spring 42, under the unidirectional memory effect, returns to its memory shape. At this point, the SMA spring 42 will overcome the elastic force of the bias spring 44, pulling the energy-conducting bridge plate 43 away from the energy storage chamber 41, thus breaking the heat transfer and preventing the heat from the outer cylinder 2 from being transferred to the energy storage chamber 41, ensuring that the energy storage medium inside the energy storage chamber 41 remains at a low temperature. Simultaneously, when the aircraft lands, the piston outer rod 53 will be subjected to… Due to the pre-cooling of the hydraulic oil, the massive instantaneous impact generates greater damping force during the impact, providing a better buffering and support effect. Since it is used on aircraft landing gear, which is not a scenario where the hydraulic oil needs to circulate, but only needs to protect the aircraft body in a one-time extreme impact, the pre-cooling will not affect the working response efficiency. It can also reduce the peak temperature rise caused by the heat generated by the hydraulic oil when it is impacted, and limit the heat diffusion to the inner wall of the inner cylinder 3, thereby preventing the inner wall of the inner cylinder 3 and the inner piston rod 52 from deforming due to temperature rise and massive instantaneous impact load.

[0049] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as defined by the appended claims and their equivalents.

Claims

1. A surface-adaptive anti-deformation actuator, comprising an oil guide (1), characterized in that: It also includes an outer cylinder (2), an inner cylinder (3), an energy storage assembly (4), and a piston assembly (5); the outer cylinder (2) is connected to the oil guide (1); the inner cylinder (3) is disposed inside the outer cylinder (2); the energy storage assembly (4) is disposed between the outer cylinder (2) and the inner cylinder (3), when the temperature is higher than a certain value, the energy storage assembly (4) and the outer cylinder (2) change from a contact state to a disconnected state, and after the temperature drops below the certain value, the energy storage assembly (4) is reconnected to the outer cylinder (2); the piston assembly (5) is connected to the energy storage assembly (4), and when the piston assembly (5) slides, it draws the energy storage medium in the energy storage assembly (4) into the piston assembly (5); A vacuum layer one (6) is provided between the outer cylinder (2) and the energy storage component (4); a vacuum layer two (7) is provided between the energy storage component (4) and the inner cylinder (3); The energy storage assembly (4) includes an energy storage chamber (41), an SMA spring (42), an energy-conducting bridge plate (43), an offset spring (44), and a fixing member (45); the energy storage chamber (41) is disposed between vacuum layer one (6) and vacuum layer two (7); the SMA spring (42) is connected to the energy storage chamber (41); the energy-conducting bridge plate (43) is connected to the SMA spring (42); the offset spring (44) is connected between the energy-conducting bridge plate (43) and the SMA spring (42); the fixing member (45) is connected to the energy storage chamber (41), and the outer ring of the fixing member (45) is connected to the inner wall of the outer cylinder (2), and the inner ring of the fixing member (45) is connected to the outer wall of the inner cylinder (3).

2. The surface adaptive anti-deformation actuator according to claim 1, characterized in that: The cold energy storage medium in the energy storage chamber (41) is a fluorinated liquid; the fixing component (45) is made of PEEK material; the energy-conducting bridge plate (43) is made of a material with high thermal conductivity, and the energy-conducting bridge plate (43) is an arc plate structure with an inner wall radius equal to the outer wall radius of the energy storage chamber (41).

3. The surface adaptive anti-deformation actuator according to claim 1, characterized in that: The piston assembly (5) includes a piston head (51), an inner piston rod (52), an outer piston rod (53), and a cooling component (54); the piston head (51) is slidably mounted inside the inner cylinder (3); the inner piston rod (52) is mounted on the central axis of the inner cylinder (3); the outer piston rod (53) is connected to the piston head (51) and slidably mounted on the inner piston rod (52); the cooling component (54) is connected between the energy storage chamber (41) and the inner piston rod (52).

4. The surface adaptive anti-deformation actuator according to claim 3, characterized in that: The cooling component (54) includes a cooling chamber (541), a connecting pipe (542), and a liquid-drawing piston (543); the cooling chamber (541) is located inside the piston inner rod (52); the connecting pipe (542) is connected between the piston inner rod (52) and the energy storage chamber (41); the liquid-drawing piston (543) is slidably installed in the cooling chamber (541) and connected to the piston outer rod (53).

5. The surface adaptive anti-deformation actuator according to claim 4, characterized in that: The piston inner rod (52) has a liquid inlet channel (521) at its tail end, and the liquid inlet channel (521) is connected to the cooling chamber (541); the head of the connecting pipe (542) and the liquid pumping piston (543) are made of PEEK material, and the tail end of the connecting pipe (542) is installed in the liquid inlet channel (521).

6. The surface adaptive anti-deformation actuator according to claim 4, characterized in that: The inner diameter of the piston head (51) and the piston outer rod (53) is equal to the outer wall diameter of the piston inner rod (52), and the outer edge of the piston head (51) is provided with a pressure-resistant rounded corner (511); the liquid-drawing piston (543) is a rod-shaped structure, and the outer diameter of the liquid-drawing piston (543) is equal to the inner wall diameter of the cooling chamber (541).

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