Thermal protection device for aircraft steering engine

Abstract

The invention discloses a thermal protection device for an aircraft steering engine, and belongs to the technical field of steering engines. The technical problem that a traditional thermal protection mode cannot prevent a rudder shaft of an aircraft from directly transferring heat to the interior of a steering engine is solved. The rudder system comprises a rudder surface, a rudder shaft and a steering engine, the control surface is connected with the steering engine through the rudder shaft; the steering engine comprises a steering engine frame and a metal shaft sleeve assembly. An angle sensor is arranged on the steering engine frame; the metal shaft sleeve assembly comprises a metal shaft sleeve; one end of the metal shaft sleeve is connected with the rudder shaft, the other end is connected with the sensor, one end of the metal shaft sleeve connected with the rudder shaft is provided with a first thermal protection component, and one end connected with the sensor is provided with a second thermal protection component; the first thermal protection component is used for blocking heat transmitted from the rudder shaft to the steering engine frame; the second thermal protection component is used for blocking heat transmitted from the rudder shaft to the sensor. Heat conducted from the rudder shaft to the steering engine can be reduced, and normal work of the steering engine at high temperature is guaranteed.

Description

Technical Field

[0001] This invention relates to the field of thermal protection devices, and more particularly to a thermal protection device for aircraft servo motors. Background Technology

[0002] Servo servos are a crucial component of aircraft control systems, containing numerous electronic components that cannot function properly in high-temperature environments. Aircraft need to maintain high-speed flight for extended periods within the atmosphere, resulting in intense friction between the aircraft surface and control surfaces and atmospheric airflow, generating significant heat. This heat is directly transferred to the servo servos via the control shaft, causing a rapid increase in internal temperature. This poses a significant threat to the stability of the internal electronic equipment, thus requiring robust thermal protection design to enhance the reliability of servos in high-temperature environments.

[0003] Most servos operate in a thermal environment characterized by high-temperature heat flow and radiation from their outer surfaces. To address this, heat-insulating coatings or materials are typically applied to the servo's outer surface to reduce external heat transfer. This thermal protection method effectively solves the problem of internal temperature rise caused by direct heat transfer from the servo's outer surface. However, during high-speed, long-duration flight, the control surfaces generate a significant amount of heat. This heat can be directly transferred into the servo's interior through the control shaft connection, causing a rapid increase in internal temperature and potentially damaging electronic components. For this type of thermal environment, traditional methods of adding heat-insulating coatings to the outer surface are insufficient to prevent heat transfer directly from the control surfaces and shaft. Summary of the Invention

[0004] Based on the above analysis, the present invention aims to provide a hypersonic vehicle rudder system with a thermal protection structure to solve the technical problem that traditional thermal protection methods cannot prevent the vehicle rudder shaft from directly transferring heat to the inside of the rudder mechanism.

[0005] The objective of this invention is mainly achieved through the following technical solutions:

[0006] This invention provides a hypersonic vehicle control system with a thermal protection structure, including control surfaces, control shafts, and servo motors; the control surfaces are connected to the servo motors via the control shafts.

[0007] The servo motor includes a servo motor frame and a metal bushing assembly; a sensor is mounted on the servo motor frame; the metal bushing assembly includes a metal bushing; one end of the metal bushing is connected to the servo shaft, and the other end is connected to the sensor; the end of the metal bushing connected to the servo shaft is provided with a first thermal protection component, and the end connected to the sensor is provided with a second thermal protection component.

[0008] The first thermal protection component is used to block heat transmitted from the rudder shaft to the servo frame; the second thermal protection component is used to block heat transmitted from the rudder shaft to the sensor.

[0009] In one possible design, the metal bushing has a first cylindrical section and a second cylindrical section at both ends; the first cylindrical section is provided with a first rolling bearing and a second rolling bearing; and the second cylindrical section is provided with a third rolling bearing.

[0010] In one possible design, the first rolling bearing and the second rolling bearing are coaxial and parallel, and the first thermal protection component is located on the contact surface between the first cylindrical section and the inner rings of the first rolling bearing and the second rolling bearing.

[0011] In one possible design, the first cylindrical section is a hollow structure, and one end of the rudder shaft is embedded in the first cylindrical section of the metal bushing and rigidly connected to the metal bushing via a spline.

[0012] In one possible design, the first thermal protection component is a heat-insulating bushing, which is fitted onto the outer surface of the first cylindrical section.

[0013] In one possible design, the thickness of the heat-insulating bushing is 1 / 2 to 2 / 3 of the thickness of the metal bushing.

[0014] In one possible design, the second insulation component is an insulation bushing;

[0015] The heat insulation bushing is installed at the end of the second cylindrical section of the metal bushing with an interference fit.

[0016] In one possible design, the heat-insulating bushing and bushing are made of bismaleimide resin system materials.

[0017] In one possible design, the thermal conductivity of the bismaleimide resin system material is 0.3-0.4 W / mK.

[0018] In one possible design, the outer rings of the first rolling bearing, the second rolling bearing, and the third rolling bearing are all mounted on the servo frame;

[0019] The first rolling bearing, the second rolling bearing, and the third rolling bearing are axially fixed by cover plates and corresponding screws.

[0020] Compared with the prior art, the present invention can achieve at least one of the following beneficial effects:

[0021] (1) The present invention provides a first heat-insulating bushing on the outer surface of the first cylindrical section of the metal bushing and a second heat-insulating bushing on the outer surface of the second cylindrical section of the metal bushing. By using the first heat-insulating bushing, the second heat-insulating bushing, and the heat-insulating bushing to partially replace the alloy with a high thermal conductivity, most of the heat transmitted from the rudder shaft is blocked on the metal bushing, which slows down and reduces the speed at which heat is transmitted from the bearing to the servo motor. At the same time, it ensures that the rudder shaft and the metal bushing are rigidly connected to transmit the output torque. This greatly reduces the size of the thermal protection structure, achieves efficient heat protection performance in a limited internal space, significantly reduces the overall temperature of the servo motor, improves the reliability of the servo motor when the rudder shaft is in continuous high temperature condition, and greatly enhances the high temperature resistance of the servo motor.

[0022] (2) The present invention provides a heat insulation bushing at the end of the second cylindrical section of the metal bushing, that is, a heat insulation bushing is provided between the metal bushing and the sensor, which can effectively reduce the heat transmitted through the rudder shaft to the inside of the sensor, thereby reducing the working temperature of the sensor.

[0023] In this invention, the above-described technical solutions can be combined with each other to achieve more preferred combinations. Other features and advantages of this invention will be set forth in the following description, and some advantages may become apparent from the description or be learned by practicing the invention. The objects and other advantages of this invention can be realized and obtained through the embodiments described and the accompanying drawings, which are particularly pointed out. Attached Figure Description

[0024] The accompanying drawings are for illustrative purposes only and are not intended to limit the invention. Throughout the drawings, the same reference numerals denote the same parts.

[0025] Figure 1 Schematic diagram of a typical servo motor;

[0026] Figure 2a This is a schematic diagram of the structure of the metal bushing before the thermal protection component is installed;

[0027] Figure 2b A schematic diagram of the installation position of the metal bushing of the present invention;

[0028] Figure 3 This is a cross-sectional view of the servo motor of the present invention;

[0029] Figure 4a This is a schematic diagram of the structure of the metal bushing of the present invention after the thermal protection component is installed;

[0030] Figure 4b This is a schematic diagram of the metal bushing of the present invention and its installation position;

[0031] Figure 5 This is a composition diagram of the metal bushing of the present invention;

[0032] Figure 6a This is an actual example of a metal bushing with a heat-protected component installed according to the present invention. Figure 1 ;

[0033] Figure 6b Figure 2 shows the actual metal bushing with the heat protection component installed according to the present invention;

[0034] Figure 7 This is a schematic diagram of the heating rod temperature rise curve during the thermal testing of the servo motor of the present invention.

[0035] 1-Servo motor; 2-Servo shaft; 3-Servo surface; 4-Servo motor frame; 5-Sensor; 6-Motor; 7-Driver; 8-First rolling bearing; 9-Second rolling bearing; 10-Third rolling bearing; 11-Metal bushing; 12-Insulation bushing mounting hole; 13-Insulation bushing; 14-First insulation bushing; 15-Second insulation bushing; 16-Insulation pad; 17-Heating rod; 18-Heating temperature measuring point. Detailed Implementation

[0036] The preferred embodiments of the present invention will now be described in detail with reference to the accompanying drawings, which constitute a part of the present invention and are used together with the embodiments of the present invention to illustrate the principles of the present invention, but are not intended to limit the scope of the present invention.

[0037] During flight, a large amount of heat is transferred from the rudder shaft 2 to the servo motor 1. Since the parts in the servo motor 1 are made of high-strength alloy steel, the heat will be quickly transferred from the rudder shaft 2 to the servo motor 1, causing the internal components of the servo motor 1 to fail at high temperatures, and ultimately causing the servo motor 1 to malfunction.

[0038] To address the aforementioned problems, the present invention requires a thermal protection design for the servo motor 1, such as... Figures 1 to 7 As shown, to ensure that the servo motor 1 can operate normally under the condition of continuous high temperature of the servo shaft 2, the present invention provides a hypersonic vehicle servo system with a thermal protection structure. The vehicle servo system includes a control surface 3, a servo shaft 2, and a servo motor 1; the control surface 3 is connected to the servo motor 1 through the servo shaft 2; the servo motor 1 includes a servo motor frame 4 and a metal bushing assembly; a sensor 5 is provided on the servo motor frame 4; the metal bushing assembly includes a metal bushing 11; one end of the metal bushing 11 is connected to the servo shaft 2, and the other end is connected to the sensor 5. The end of the metal bushing 11 connected to the servo shaft 2 is provided with a first thermal protection component, and the end connected to the sensor 5 is provided with a second thermal protection component; the first thermal protection component is used to block the heat transmitted from the servo shaft 2 to the servo motor frame 4; the second thermal protection component is used to block the heat transmitted from the servo shaft 2 to the sensor 5.

[0039] Specifically, the servo motor 1 is rigidly connected to the control surface 3 via the control shaft 2. Coaxial rotation of the control surface 3 deflects the servo motor, thereby changing the aircraft's flight attitude. The servo motor 1 includes a servo frame 4 and a metal bushing assembly. The servo frame 4 provides a robust support structure for the servo motor 1, securing other components (e.g., the sensor 5, driver 7, and motor 6 are all mounted on the servo frame 4) and preventing relative displacement during operation. The metal bushing assembly is the power output device connecting the servo motor 1 and the control shaft 2, converting the rotational output of the motor 6 into the rotational output of the servo motor 1. The metal bushing assembly includes a metal bushing 11. The end of the metal bushing 11 rigidly connected to the control shaft 2 has a first thermal protection component; the end of the metal bushing 11 connected to the sensor 5 has a second thermal protection component.

[0040] Compared with the prior art, the present invention reduces the operating temperature of the electrical components in the servo frame 4 and improves its reliability by setting a first thermal protection component to block most of the heat transmitted from the rudder shaft 2 to the servo frame 4 and setting a second thermal protection component to block most of the heat transmitted from the rudder shaft 2 to the sensor 5.

[0041] It should be noted that the two ends of the metal bushing 11 of the present invention are a first cylindrical section and a second cylindrical section, respectively; a first rolling bearing 8 and a second rolling bearing 9 are provided on the first cylindrical section; a third rolling bearing 10 is provided on the second cylindrical section; the first rolling bearing 8 and the second rolling bearing 9 are coaxial and parallel, and a first thermal protection component is provided on the contact surface between the first cylindrical section and the inner rings of the first rolling bearing 8 and the second rolling bearing 9.

[0042] Compared with the prior art, the present invention can effectively block most of the heat conducted from the rudder shaft 2 to the first rolling bearing 8 and the second rolling bearing 9 by setting a first thermal protection component on the first cylindrical section of the metal bushing 11, thereby slowing down the speed at which heat is transferred from the first rolling bearing 8 and the second rolling bearing 9 to the servo motor 1.

[0043] It should be noted that the metal bushing 11 of the present invention is also provided with a third heat protection component, which is located on the contact surface between the second cylindrical section and the inner ring of the third rolling bearing 10.

[0044] It should be emphasized that the third thermal protection component is made of the same material as the first and second thermal protection components. The third thermal protection component is used to further reduce the heat conduction from the metal bushing 11 to the sensor 5.

[0045] It should be noted that the first cylindrical section and the second cylindrical section of the present invention are both hollow structures with the same thickness. One end of the rudder shaft 2 is embedded in the first cylindrical section of the metal bushing 11 and is rigidly connected to the metal bushing 11 through a spline.

[0046] To achieve efficient heat protection for the metal bushing 11, such as Figure 3 As shown in Figure 4, the first thermal protection component is a first thermal insulation bushing 14, which is disposed on the outer surface of the first cylindrical section; the third thermal protection component is a second thermal insulation bushing 15, which is disposed on the outer surface of the second cylindrical section, and the first thermal insulation bushing 14 and the second thermal insulation bushing 15 have the same thickness.

[0047] It should be emphasized that the metal bushing 11 of the present invention has a hollow structure, and the thickness of the first heat-insulating bushing 14 and the second heat-insulating bushing 15 is 1 / 2 to 2 / 3 of the thickness of the metal bushing 11. Controlling the thickness of the first heat-insulating bushing 14 and the second heat-insulating bushing 15 within the above-mentioned range can improve the thermal protection performance of the metal bushing 11 while maintaining structural strength. The actual objects of the first heat-insulating bushing 14 and the second heat-insulating bushing 15 are shown below. Figure 6a As shown.

[0048] It should be noted that the second heat insulation component of the present invention is a heat insulation bushing 13, and the actual heat insulation bushing 13 is shown in the figure. Figure 6b As shown; the end of the second cylindrical section of the metal bushing 11 is provided with a heat insulation bushing mounting hole 12, and the heat insulation bushing 13 is installed in the heat insulation bushing mounting hole 12 with an interference fit.

[0049] Specifically, the heat insulation bushing 13 is installed at the end of the second cylindrical section of the metal bushing 11 with an interference fit. The heat insulation bushing 13 can not only be used to isolate the heat conduction between the second cylindrical section of the metal bushing 11 and the sensor 5, and prevent heat from being conducted from the metal bushing 11 to the sensor 5, but also be used to connect the output shaft of the sensor 5 and be installed coaxially with the sensor 5, so as to detect the output angle of the servo motor 1 output shaft.

[0050] It should be emphasized that the first heat-insulating bushing 14, the second heat-insulating bushing 15, and the heat-insulating bushing 13 are all made of bismaleimide resin system material. The thermal conductivity of the bismaleimide resin system material is 0.3W / mK-0.4W / mK (the thermal conductivity of the existing metal bushing 11 is 50W / mK-60W / mK, which is relatively large). The compressive strength of the bismaleimide resin system material is 532MPa. The bismaleimide resin system material can withstand a high temperature environment of 260℃ for a long time. This invention greatly reduces the size of the heat protection structure without changing the overall size of the rudder system, ensuring efficient heat protection performance in a limited internal space.

[0051] As shown in Figure 4 and Figure 5As shown, in this invention, the metal bushing at the end of the second cylindrical section of the metal bushing 11 is replaced with a heat-insulating bushing 13 made of a bismaleimide resin system material. The heat-insulating bushing 13 is manufactured by pressing at 230°C and 8 MPa for 2 hours. Compared with existing metal bushing parts, the heat-insulating bushing 13 of this invention can effectively block the heat transmitted from the rudder shaft 2 to the sensor 5, significantly reducing the operating temperature of the sensor 5 and improving the reliability of the sensor 5.

[0052] It should be noted that the outer rings of the first rolling bearing 8, the second rolling bearing 9, and the third rolling bearing 10 of the present invention are all mounted on the servo frame 4; the first rolling bearing 8, the second rolling bearing 9, and the third rolling bearing 10 are axially fixed by cover plates and corresponding screws.

[0053] It should be noted that, as shown in Figure 4, the first rolling bearing 8, the second rolling bearing 9, and the third rolling bearing 10 of the present invention are all deep groove ball bearings, and the three deep groove ball bearings are mounted on the metal bushing 11 by an interference fit. In addition, the motor 6, the driver 7, and the sensor 5 are all fixed to the servo frame 4 by contact with the stop surface and screws.

[0054] In order to effectively reduce the heat conduction from the rudder shaft 2 to the driver 7, a heat insulation pad 16 is provided between the driver 7 and the servo frame 4 of the present invention. The heat insulation pad 16 is also made of bismaleimide resin system material.

[0055] In summary, by providing a first heat-insulating bushing and a second heat-insulating bushing 15 on the first and second cylindrical sections of the metal bushing 11, and a heat-insulating bushing 13 at the end of the second cylindrical section, this invention can block and slow down the transmission of heat from the rudder shaft 2 to the driver 7, sensor 5, and motor 6 through the path of rudder shaft 2-metal bushing 11-bearing-servo frame 4 when a large amount of heat is transmitted to the servo motor 1 during the flight of the aircraft. This avoids the failure of internal components at high temperatures due to the rapid increase in temperature of the driver 7, sensor 5, and motor 6, and ultimately prevents the servo motor 1 from failing to work properly.

[0056] To verify the thermal protection effect of the present invention, a thermal test was conducted on a servo motor 1 equipped with a first thermal insulation bushing 14, a second thermal insulation bushing 15, and a thermal insulation bushing 13. The physical examples of the first thermal insulation bushing 14 and the second thermal insulation bushing 15 are shown below. Figure 6a As shown, the actual product of the heat insulation bushing 13 is as follows: Figure 6b As shown, the specific process includes the following:

[0057] Step 1: Determine the test subjects;

[0058] The test objects include: test piece 1 and test piece 2; wherein, test piece 1 is a servo motor 1 without thermal protection components installed; test piece 2 is a servo motor 1 with thermal protection components installed.

[0059] Step 2: Determine the test equipment;

[0060] The experimental equipment includes an electric heating element, a K-type thermocouple thermometer, and a SPARTAN data acquisition system.

[0061] Step 3: Determine the experimental methods and conditions;

[0062] Four temperature measuring points are simultaneously arranged at the same positions on test specimens 1 and 2. These four points are: T1 (lead screw), T2 (sensor 5), T3 (driver 7), and T4 (motor 6). A heating temperature measuring point 18 (any point on the heating rod 17) is arranged on the heating rod 17. A heat insulation felt is used between the heating rod 17 and test specimen 1 or 2 to reduce the influence of heat convection. After the test begins, the heating rod 17 is heated, and the heating curve of the heating rod 17 is shown below. Figure 7 As shown.

[0063] Step 4, Experimental Results;

[0064] During the entire heating process of heating rod 17, a total of 8 temperature measuring points of test piece 1 and test piece 2 were measured. The temperature of each measuring point during the test is shown in Table 1-Table 2.

[0065] Table 1 Temperature data of test piece 1, metal bushing 11, servo motor

[0066] T1 (lead screw) T2 (Sensor 5) T3 (Driver 7) T4 (Motor 6) Starting temperature / ℃ 25 26 14 14 Maximum temperature / °C 111 117 55 53 Maximum temperature rise / ℃ 86 91 41 39

[0067] Table 2 Temperature data of the servo motor with heat insulation bushing of test piece 2

[0068] T1 (lead screw) T2 (Sensor 5) T3 (Driver 7) T4 (Motor 6) Starting temperature / ℃ 24 20 19 19 Maximum temperature / °C 74 52 40 39 Maximum temperature rise / ℃ 50 32 21 20

[0069] By comparing the data in Table 1 and Table 2, it can be seen that the highest temperature at point T1 (lead screw) dropped by 37℃, the highest temperature at point T2 (sensor 5) dropped by 65℃, the highest temperature at point T3 (driver 7) dropped by 15℃, and the highest temperature at point T4 (motor 6) dropped by 14℃.

[0070] The test results show that the temperatures of test piece 2 (servo motor 1 with thermal protection components) at points T1 to T4 are significantly lower than those of test piece 1 (servo motor 1 without thermal protection components), indicating that the heat protection effect of the first heat insulation bushing 14, the second heat insulation bushing 15, and the heat insulation bushing 13 is obvious.

[0071] Compared with the prior art, firstly, the present invention provides a first heat-insulating bushing 14 on the outer surface of the first cylindrical section of the metal bushing 11, with the inner ring surface of the first heat-insulating bushing 14 contacting the outer surface of the first cylindrical section, and the outer ring surface of the first heat-insulating bushing 14 contacting the inner ring surfaces of the first rolling bearing 8 and the second rolling bearing 9; secondly, a second heat-insulating bushing 15 is provided on the outer surface of the second cylindrical section of the metal bushing 11, with the inner ring surface of the second heat-insulating bushing 15 contacting the outer surface of the second cylindrical section, and the outer ring surface of the second heat-insulating bushing 15 contacting the inner ring surface of the third rolling bearing 10; utilizing the first heat-insulating bushing 14... 4. The second heat-insulating bushing 15 and the heat-insulating bushing 13 partially replace the alloy with a high thermal conductivity, blocking most of the heat transmitted from the rudder shaft 2 onto the metal bushing 11. This slows down and reduces the speed at which heat is transmitted from the bearings (including the first rolling bearing 8 to the third rolling bearing 10) to the servo motor 1. At the same time, it ensures that the rudder shaft 2 is rigidly connected to the metal bushing 11 to transmit the output torque. This greatly reduces the size of the thermal protection structure, achieves efficient heat protection performance in a limited internal space, significantly reduces the overall temperature of the servo motor 1, improves the reliability of the servo motor 1 under continuous high temperature conditions of the rudder shaft 2, and greatly enhances the high temperature resistance of the servo motor 1.

[0072] Secondly, the present invention provides a heat insulation bushing 13 at the end of the second cylindrical section of the metal bushing 11, that is, a heat insulation bushing 13 is provided between the metal bushing 11 and the sensor 5, which can effectively reduce the heat transmitted through the rudder shaft 2 to the inside of the sensor 5, thereby reducing the operating temperature of the sensor 5.

[0073] Furthermore, the first heat-insulating bushing 14, the second heat-insulating bushing 15, and the heat-insulating bushing 13 of the present invention are all made of bismaleimide resin system material that can withstand 260°C for a long time. The bismaleimide resin system material is combined with the metal substrate through the existing winding process and then wound on the outer surface of both ends of the metal bushing. While keeping the overall size of the rudder system unchanged, the size of the heat protection structure is greatly reduced, and efficient heat protection performance is achieved in a limited internal space.

[0074] The above description is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto. Any changes or substitutions that can be easily conceived by those skilled in the art within the scope of the technology disclosed in the present invention should be included within the scope of protection of the present invention.

Claims

1. A heat shield for an aircraft rudder, characterized in that The rudder shaft is connected with the rudder machine; The rudder machine comprises a rudder machine frame and a metal shaft sleeve assembly; a sensor is arranged on the rudder machine frame; the metal shaft sleeve assembly comprises a metal shaft sleeve; one end of the metal shaft sleeve is connected with the rudder shaft, and the other end is connected with the sensor; a first heat protection component is arranged at the end of the metal shaft sleeve connected with the rudder shaft, and a second heat protection component is arranged at the end of the metal shaft sleeve connected with the sensor; The first heat protection component is used for blocking heat transmitted from the rudder shaft to the rudder machine frame; and the second heat protection component is used for blocking heat transmitted from the rudder shaft to the sensor.

2. The thermal protection device for an aircraft rudder machine according to claim 1, characterized in that, Both ends of the metal shaft sleeve are respectively a first cylindrical segment and a second cylindrical segment; a first rolling bearing and a second rolling bearing are arranged on the first cylindrical segment; and a third rolling bearing is arranged on the second cylindrical segment.

3. The thermal protection device for an aircraft rudder machine according to claim 2, characterized in that, The first rolling bearing and the second rolling bearing are coaxial and parallel; and the first heat protection component is arranged on the contact surface between the first cylindrical segment and the inner rings of the first rolling bearing and the second rolling bearing.

4. The thermal protection system for an aircraft rudder as defined in claim 3, wherein, The first cylindrical segment is a hollow structure; one end of the rudder shaft is embedded in the first cylindrical segment of the metal shaft sleeve and rigidly connected with the metal shaft sleeve through a spline.

5. The thermal protection system for an aircraft rudder as defined in claim 3, wherein, The first heat protection component is a first heat insulation sleeve; and the first heat insulation sleeve is arranged on the outer circular surface of the first cylindrical segment.

6. The thermal protection device for an aircraft rudder machine according to claim 5, characterized in that, The thickness of the first heat insulation sleeve is 1 / 2-2 / 3 of the thickness of the first cylindrical segment of the metal shaft sleeve.

7. The thermal protection device for an aircraft rudder machine according to claim 6, characterized in that, The second heat protection component is a heat insulation bushing; The heat insulation bushing is installed at the end of the second cylindrical segment of the metal shaft sleeve.

8. The thermal protection device for an aircraft rudder machine according to claim 7, characterized in that, The materials of the first heat insulation sleeve and the heat insulation bushing are both selected from a bismaleimide resin system material.

9. The thermal protection device for an aircraft actuator of claim 8, wherein, The thermal conductivity of the bismaleimide resin system material is 0.3 W / mK-0.4 W / mK.

10. Heat protection device for an aircraft rudder machine according to any one of claims 3 to 9, characterized in that, The bearing outer rings of the first rolling bearing, the second rolling bearing and the third rolling bearing are all installed on the rudder machine frame; The first rolling bearing, the second rolling bearing and the third rolling bearing are axially fixed through a cover plate and corresponding screws.

Images