A thermal protection device for external camera of high-speed aircraft

Abstract

The invention discloses a thermal protection device for an external camera of a high-speed aircraft, comprising an aircraft cabin wall, a reflector protective shell, an external perspective glass, a reflector fixing pin, a reflector, an internal perspective glass, a camera bracket, a camera vibration damper, a camera, a camera sealing pad, a camera cable and an electrical connector, wherein the reflector protective shell is installed outside the aircraft cabin, the external perspective glass is fixed in the reflector protective shell, two reflector fixing pins are respectively installed inside the reflector protective shell for installing the reflector, the side of the reflector reflecting light faces the external perspective glass, and the internal perspective glass is installed on the aircraft cabin wall. The size of the components outside the aircraft cabin of the invention is smaller than that of directly installing the camera outside the aircraft, so the aerodynamic heating generated is smaller and the impact on the aerodynamic shape of the aircraft is smaller.

Description

Technical Field

[0001] The present invention relates to a thermal protection device for an external camera of a high-speed aircraft, belonging to the technical field of structural thermal protection. Background Art

[0002] During the execution of an aircraft mission, it is sometimes necessary to capture the changes in the state of the aircraft's outer surface and the external environment. During high-speed flight, the outer surface of the aircraft's fuselage is heated by high-speed friction between the outer surface of the aircraft's cabin wall and the air, resulting in a high temperature of several hundred to thousands of degrees Celsius. The maximum temperature at which the electronic components in the camera can work normally is 125°C, which is much lower than the ambient temperature during flight. Therefore, the camera needs to be thermally protected to keep the camera's operating ambient temperature within the allowable range.

[0003] There are two conventional thermal protection methods:

[0004] One method is to install the camera outside the aircraft, wrap the camera with insulation materials such as quartz wool or insulation tiles, and place translucent quartz glass in front of the lens to slow down the conduction of heat to the camera. The disadvantage of this method is that the volume of the extravehicular components is large, which has a greater impact on the shape of the aircraft and causes significant changes in the aerodynamic characteristics of the aircraft. In addition, in order to maintain the operating temperature of the camera, thicker insulation materials are required. The increase in the volume of the material will lead to an increase in aerodynamic heating.

[0005] Another method has a working principle similar to that of an endoscope. The camera is installed in the aircraft cabin, and a small lens is placed outside the cabin separately. The lens is connected to the camera through a flexible optical fiber, and insulation material is wrapped around the lens. Transparent quartz glass is placed in front of the lens. The advantage of this method is that the device placed outside the aircraft is small in size, but the disadvantage is that the optical resolution and clarity of the captured image are low, and the maximum temperature that the coating material on the lens surface can withstand is about 200°C. The high temperature environment causes the transmission performance of the coating to change, resulting in a further decrease in image clarity. Summary of the invention

[0006] The technical problem solved by the present invention is: to overcome the deficiencies of the prior art and to propose a thermal protection device for an external camera of a high-speed aircraft, which has the characteristics of reducing the working environment temperature of the external camera and affecting the aerodynamic shape of the aircraft.

[0007] The technical solution of the present invention is:

[0008] A high-speed aircraft external camera thermal protection device, comprising: an aircraft cabin wall, a reflector protection shell, an external perspective glass, a reflector fixing pin, a reflector, an internal perspective glass, a camera bracket, a camera vibration damper, a camera, a camera sealing pad and a camera cable;

[0009] The reflector protection shell is installed outside the aircraft cabin and connected to the aircraft cabin wall. The angle between the plane where the external perspective glass is installed and the aircraft cabin wall is A.

[0010] The external perspective glass is fixed in the through hole of the reflector protective shell by using high temperature glue, and is flush with the outer surface of the reflector protective shell. The high temperature glue can also reduce the high-frequency vibration transmitted from the reflector protective shell to the external perspective glass;

[0011] Two reflector fixing pins are respectively installed inside the reflector protection shell, and the reflector is fixed between the two reflector fixing pins. The side of the reflector reflecting light faces the external perspective glass, and the angle between the side and the aircraft cabin wall is B;

[0012] The built-in perspective glass is fixed in the through hole of the aircraft cabin wall with high temperature glue, flush with the outer surface of the aircraft cabin wall. The high temperature glue also plays a role in reducing the high-frequency vibration transmitted from the aircraft cabin wall to the built-in perspective glass;

[0013] The camera bracket is fixed on the inner side of the aircraft cabin wall, the camera is fixed on the camera bracket through a camera vibration damper, the camera lens faces the built-in perspective glass, a camera sealing pad is laid between the camera bracket and the camera and fixed on one side of the camera bracket, and the camera cable passes through the through hole of the camera bracket and the camera sealing pad to connect the camera with the internal equipment of the aircraft cabin;

[0014] The incident light passes through the external perspective glass and hits the reflector. After being reflected, it passes through the internal perspective glass and hits the camera lens.

[0015] Furthermore, the aircraft cabin wall, reflector protective shell, and camera bracket are all laid out in layers by metal and thermal insulation materials. When the inner layer is a metal layer, the outer layer is a thermal insulation layer; when the inner layer is a thermal insulation layer, the outer layer is a metal layer.

[0016] Furthermore, the angle A between the external transparent glass and the aircraft cabin wall can be adjusted according to mission requirements, and the adjustment range is 0° to 90°.

[0017] Furthermore, by adjusting the position of the reflector fixing pin, the included angle B between the reflector and the aircraft cabin wall can be adjusted within a range of 0° to 90°.

[0018] Furthermore, according to the task requirements, the reflector can be a plane mirror, a concave mirror or a convex mirror. Different reflectors can expand or reduce the field of view of the camera.

[0019] Furthermore, the aircraft cabin wall, the built-in transparent glass, the camera bracket and the camera sealing gasket form a sealed space, and the camera bracket and the camera sealing gasket reserve a through hole for passing the camera cable.

[0020] Furthermore, the reflector includes quartz glass, a reflective coating and a base.

[0021] The reflective coating is on the side of the quartz glass close to the base, and can be made of aluminum or silver materials according to the needs of reflecting different wavelengths of light in the task and the ambient temperature; the quartz glass is installed closely to the base, and the quartz glass does not contact the fixing pins of the reflector;

[0022] The base is connected to the reflector fixing pin, and a movable gap is left at the fixing position to prevent the quartz glass from breaking and prevent heat from being conducted to the reflective coating, thereby ensuring the reflective performance of the reflective coating to light.

[0023] Furthermore, when the angle B is less than 45°, the reflector can reflect light from the outer surface of the aircraft cabin wall to the camera; when the angle B is equal to 45°, the reflector can reflect light parallel to the aircraft cabin wall to the camera; when B is greater than 45°, the reflector can reflect light from the external environment of the aircraft to the camera.

[0024] Furthermore, when the external components of the cabin are damaged due to the influence of a harsh environment, the built-in transparent glass can prevent the hot air flow outside the aircraft cabin from entering the cabin, and the built-in transparent glass assumes the anti-heat insulation function.

[0025] Furthermore, when the built-in transparent glass is broken, the camera bracket, the camera and the camera sealing pad can prevent the hot air flow outside the aircraft cabin from entering the cabin, and the camera bracket assumes the anti-heat insulation function.

[0026] The beneficial effects of the present invention are:

[0027] (1) The size of the device on the outside of the aircraft cabin is smaller than that of directly mounting the camera on the outside of the aircraft, so the aerodynamic heating generated is smaller and the impact on the aerodynamic shape of the aircraft is smaller;

[0028] (2) The imaging quality of the present device is higher than that of an endoscope in which the lens and camera are placed separately;

[0029] (3) The components of the device installed outside the aircraft cabin include metal, thermal insulation material, quartz glass and reflectors. The reflectors include quartz glass and reflective coatings. The maximum temperature that the materials can withstand is much higher than the maximum temperature that the camera or lens placed outside the aircraft cabin can withstand. Therefore, the requirements for thermal protection are lower.

[0030] (4) This device has a lower cost than other camera thermal protection devices. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 This is a side view of a thermal protection device for an external camera of a high-speed aircraft according to the present invention;

[0032] Figure 2 This is a front view of a thermal protection device for an external camera of a high-speed aircraft according to the present invention;

[0033] Figure 3 The camera shooting range of the present invention is that the angle B is less than 45°;

[0034] Figure 4 The camera shooting range of the present invention is that the angle B is greater than 45°;

[0035] Figure 5 It is a structural diagram of the reflector of the present invention. DETAILED DESCRIPTION

[0036] The present invention is further described in detail below with reference to the accompanying drawings.

[0037] like Figure 1 and Figure 2 As shown, the present invention proposes a thermal protection device for an external camera of a high-speed aircraft, comprising: an aircraft cabin wall 1, a reflector protective shell 2, an external perspective glass 3, a reflector fixing pin 4, a reflector 5, an internal perspective glass 6, a camera bracket 7, a camera vibration damper 8, a camera 9, a camera sealing pad 10, and a camera cable 11.

[0038] The aircraft cabin wall 1, the reflector protective shell 2, and the camera bracket 7 are all laid in layers by metal and thermal insulation materials. When the inner layer is a metal layer, the outer layer is a thermal insulation material layer, which can be thermal insulation felt, fiberglass or ceramic; when the inner layer is a thermal insulation material layer, the outer layer is a metal layer.

[0039] The incident light 12 passes through the external perspective glass 3 and is irradiated onto the reflector 5 . After being reflected, the incident light 12 passes through the internal perspective glass 6 and is irradiated onto the lens of the camera 9 .

[0040] The reflector protection shell 2 is connected to the aircraft bulkhead 1 by screws. The metal component of the reflector protection shell 2 has a threaded blind hole. The aircraft bulkhead 1 is provided with a through hole at a corresponding position. The screws are passed through the aircraft bulkhead 1 from the inside of the aircraft and connected to the reflector protection shell 2, so that the reflector protection shell 2 is fixed to the aircraft bulkhead 1. The angle between the plane where the external perspective glass 3 of the reflector protection shell 2 is installed and the aircraft bulkhead 1 is A. According to the mission requirements, the angle A can be adjusted between 0° and 90° to adapt to the shape of the aircraft.

[0041] The reflector protective shell 2 has a protruding step on the inner side of the window on which the external perspective glass 3 is installed, which is used to fix the external perspective glass 3. A high temperature resistant glue is applied between the reflector protective shell 2 and the external perspective glass 3 for bonding and fixing. The overall thickness of the reflector protective shell 2 is the sum of the thickness of the external perspective glass 3, the protruding step of the reflector protective shell 2, and the high temperature glue, so that the outer surface of the external perspective glass 3 is flush with the outer surface of the reflector protective shell 2, and there is no step, so as to avoid aerodynamic heating. The high temperature glue also plays a role in reducing the high frequency vibration transmitted from the reflector protective shell 2 to the external perspective glass 3.

[0042] Two reflector fixing pins 4 are installed inside the reflector protective shell 2 by screws. The reflector 5 is fixed between the two reflector fixing pins 4 and connected by screws. The side of the reflector 5 that reflects light faces the external perspective glass 3, and the angle between the reflector 5 and the aircraft cabin wall 1 is B. By adjusting the positions of the two reflector fixing pins 4 and the size of the reflector 5, the angle B can be changed.

[0043] The built-in perspective glass 6 is installed in the window opening of the aircraft cabin wall 1, and there is a protruding step inside the window opening for fixing the built-in perspective glass 6. A high temperature resistant glue is applied between the aircraft cabin wall 1 and the built-in perspective glass 6 to withstand a high temperature environment. The thickness of the aircraft cabin wall 1 is the sum of the thickness of the built-in perspective glass 6, the protruding step of the aircraft cabin wall 1, and the high temperature glue. The built-in perspective glass 6 is flush with the outer surface of the aircraft cabin wall 1, and there is no step, so as to avoid aerodynamic heating. The high temperature glue also plays a role in reducing the high-frequency vibration transmitted from the aircraft cabin wall 1 to the built-in perspective glass 6.

[0044] The camera bracket 7 is fixed in the aircraft cabin on the inner side of the aircraft bulkhead 1 by screws, and the camera 9 is fixed on the camera bracket 7 by screws and the camera vibration damper 8, and the lens of the camera 9 faces the built-in perspective glass 6. A flexible camera sealing pad 10 is laid between the camera bracket 7 and the camera 9, and the camera sealing pad 10 is adhered to the camera bracket 7 using high-temperature glue. The camera bracket 7 and the camera sealing pad 10 are provided with through holes, and the camera cable 11 passes through the through holes to connect the camera 9 with the internal equipment of the aircraft cabin. The camera 9 and the camera sealing pad 10 cover the through holes, so that the aircraft bulkhead 1 and the camera bracket 7 form a sealed space.

[0045] The incident light 12 passes through the external perspective glass 3 and hits the reflector 5 . After being reflected, it passes through the internal perspective glass 6 and hits the lens of the camera 9 .

[0046] Taking into account the thermal protection requirements, the aircraft cabin wall 1, the reflector protective shell 2 and the camera bracket 7 contain metal and thermal insulation materials, which are laid in layers. The stacking order of the materials may be different depending on the mission requirements.

[0047] The angle B can be adjusted between 0° and 90°.

[0048] like Figure 1 As shown, the angle B is equal to 45°, and the reflector 5 can reflect the light parallel to the aircraft cabin wall 1 to the camera, and the camera captures the corresponding environment.

[0049] like Figure 3 As shown, the angle B is less than 45°, and the reflector 5 can reflect the light on the outer surface of the aircraft bulkhead 1 to the camera, and the camera captures the state change of the outer surface of the aircraft bulkhead.

[0050] like Figure 4As shown, the angle B is greater than 45°, and the reflector 5 can reflect the light of the external environment of the aircraft to the camera, and the camera captures the changes of the external environment of the aircraft.

[0051] When a plane mirror is used as the reflector 5, the field of view captured by the camera does not change and the shape does not distort.

[0052] When the reflector 5 uses a concave mirror, the field of view of the camera becomes smaller and the shape of the object is distorted.

[0053] When the reflector 5 uses a convex mirror, the field of view of the camera becomes larger and the shape of the object is distorted.

[0054] When the external components of the cabin fall off due to the influence of the harsh environment, the built-in perspective glass 6 ensures the isolation between the interior and the exterior of the cabin, preventing the hot air flow outside the aircraft cabin from entering the interior of the cabin. When the built-in perspective glass 6 is broken, the sealed space composed of the camera bracket 7, the camera 9 and the camera sealing pad 10 can prevent the hot air flow outside the aircraft cabin from entering the interior of the cabin. The camera bracket 7 uses heat-insulating materials, so it can assume the anti-heat insulation function, but the working environment temperature of the camera 9 is not guaranteed at this time.

[0055] like Figure 5 As shown, the reflector 5 includes quartz glass 13 , a reflective layer 14 , and a base 15 .

[0056] The reflective layer 14 is located on the side of the quartz glass 13 close to the base, and reflects the incident light 12 to the camera 9. The reflective layer 14 can be made of materials such as aluminum or silver according to the reflection requirements of different wavelengths of light in the task and the ambient temperature.

[0057] The quartz glass 13 is closely mounted to the base 15 , and a through hole is formed on the quartz glass 13 , which is fixed to the base 15 by screws 16 . The quartz glass 13 does not contact the reflector fixing pin 4 .

[0058] The reflector fixing pin 4 is composed of two layers, the top layer has a through hole, and the bottom layer has a blind hole with a thread, and the diameter of the through hole is larger than the diameter of the blind hole. The base 15 has a through hole, and the diameter is larger than the diameter of the blind hole of the bottom layer of the reflector fixing pin 4. The base 15 is placed between the top layer and the bottom layer of the reflector fixing pin 4. The screw 17 passes through the gasket 18 and the spring 19, the top layer through hole of the reflector fixing pin 4, and the through hole of the base 15, and then connects the blind hole of the bottom layer of the reflector fixing pin 4. The screw 17 is applied with a predetermined torque using a torque wrench. The base 15 has good rigidity. When the reflector protective shell 2 is deformed, the relative positions of the two reflector fixing pins 4 change. At this time, the reflector fixing pin 4 and the base 15 are relatively displaced to reduce the deformation of the base 15 and reduce the risk of quartz glass 13 breaking. The base 15 has good heat insulation ability to prevent the heat of the reflector protective shell 2 from being transferred to the reflective layer 14, thereby ensuring the reflective performance of the reflective layer 14 to light.

[0059] A specific embodiment is given below:

[0060] The outer layer of the aircraft cabin wall 1 and the reflector protection shell 2 is made of high-temperature alloy steel, and the inner layer is paved with flexible thermal insulation felt. The camera bracket 7 is made of high-temperature alloy steel, and flexible thermal insulation felt is laid on the side where the camera 9 is installed. The high-temperature alloy steel grade is GH4169, which can withstand about 700°C. The flexible thermal insulation felt is made of quartz wool, the main material of which is silicon dioxide, with a thermal conductivity of ≤0.05W / m·K, and can withstand about 1700°C.

[0061] The external perspective glass 3 and the internal perspective glass 6 are made of quartz glass, the material of which is silicon dioxide, and this material can withstand about 1700°C.

[0062] The high temperature adhesive is Dq441J-108 model, which is stable at high temperatures and can withstand about 500°C.

[0063] The reflective coating 14 uses silver, which can withstand about 961°C.

[0064] The base 15 is made of ceramic material, which has strong rigidity and good heat insulation performance and can withstand about 3000°C.

[0065] The camera sealing gasket 10 is customized using Dq441J-108 model high temperature glue, which provides better sealing and will not affect the vibration reduction performance of the camera vibration reducer 8. This material can withstand about 500°C.

[0066] The size of the device on the outside of the aircraft cabin is smaller than that of directly mounting the camera on the outside of the aircraft, so the aerodynamic heating generated is smaller and the impact on the aerodynamic shape of the aircraft is smaller.

[0067] The contents not described in detail in the present invention are well known to those skilled in the art.

Claims

1. A thermal protection device for an external camera of a high-speed aircraft, characterized in that: include: Aircraft cabin wall (1), reflector protective shell (2), external perspective glass (3), reflector fixing pin (4), reflector (5), internal perspective glass (6), camera bracket (7), camera vibration damper (8), camera (9), camera sealing pad (10) and camera cable (11); The reflector protection shell (2) is installed outside the aircraft cabin and connected to the aircraft cabin wall (1), and the angle between the plane on which the external perspective glass (3) is installed and the aircraft cabin wall (1) is A; The external perspective glass (3) is fixed in the through hole of the reflector protection shell (2) by using high temperature glue, and is flush with the outer surface of the reflector protection shell (2). The high temperature glue can also reduce the high-frequency vibration transmitted from the reflector protection shell (2) to the external perspective glass (3); Two reflector fixing pins (4) are respectively installed inside the reflector protection shell (2), and the reflector (5) is fixed between the two reflector fixing pins (4). The side of the reflector (5) that reflects light faces the external perspective glass (3), and the angle between the side and the aircraft cabin wall (1) is B; The built-in perspective glass (6) is fixed in the through hole of the aircraft cabin wall (1) by using high temperature glue, and is flush with the outer surface of the aircraft cabin wall (1). The high temperature glue also plays a role in reducing the high-frequency vibration transmitted from the aircraft cabin wall (1) to the built-in perspective glass (6); The camera bracket (7) is fixed on the inner side of the aircraft cabin wall (1); the camera (9) is fixed on the camera bracket (7) through a camera vibration damper (8); the lens of the camera (9) faces the built-in transparent glass (6); a camera sealing pad (10) is laid between the camera bracket (7) and the camera (9) and fixed on one side of the camera bracket (7); a camera cable (11) passes through the through hole of the camera bracket (7) and the camera sealing pad (10) to connect the camera (9) with the internal equipment of the aircraft cabin; The incident light (12) passes through the external perspective glass (3) and is irradiated onto the reflector (5). After being reflected, the incident light passes through the internal perspective glass (6) and is irradiated onto the lens of the camera (9).

2. A high-speed aircraft exterior camera thermal protection device according to claim 1, characterized in that: The aircraft cabin wall (1), the reflector protective shell (2) and the camera bracket (7) are all laid in layers by metal and heat insulation material. When the inner layer is a metal layer, the outer layer is a heat insulation material layer; when the inner layer is a heat insulation material layer, the outer layer is a metal layer.

3. A high-speed aircraft exterior camera thermal protection device according to claim 1, characterized in that: The included angle A between the external perspective glass (3) and the aircraft cabin wall (1) can be adjusted according to mission requirements, and the adjustment range is 0° to 90°.

4. A high-speed aircraft exterior camera thermal protection device according to claim 1, characterized in that: By adjusting the position of the reflector fixing pin (4), the included angle B between the reflector (5) and the aircraft cabin wall (1) can be adjusted, and the adjustment range is 0° to 90°.

5. The high-speed aircraft exterior camera thermal protection device according to claim 1, characterized in that: According to the task requirements, the reflector (5) can be a plane mirror, a concave mirror or a convex mirror. Different reflectors can expand or reduce the field of view of the camera.

6. A high-speed aircraft exterior camera thermal protection device according to claim 1, characterized in that: The aircraft cabin wall (1), the built-in transparent glass (6), the camera bracket (7) and the camera sealing pad (10) form a sealed space, and the camera bracket (7) and the camera sealing pad (10) reserve a through hole for passing a camera cable (11).

7. A high-speed aircraft exterior camera thermal protection device according to claim 1, characterized in that: The reflector (5) comprises quartz glass (13), a reflective coating (14) and a base (15). The reflective coating (14) is on the side of the quartz glass (13) close to the base, and can be made of aluminum or silver material according to the need to reflect light of different wavelengths in the task and the ambient temperature; the quartz glass (13) and the base (15) are installed closely, and the quartz glass (13) does not contact the reflector fixing pin (4); The base (15) is connected to the reflector fixing pin (4), and a movable gap is left at the fixing position to prevent the quartz glass (13) from breaking and prevent heat from being conducted to the reflective coating (14), thereby ensuring the reflective performance of the reflective coating (14) for light.

8. A high-speed aircraft exterior camera thermal protection device according to claim 4, characterized in that: When the angle B is less than 45°, the reflector (5) can reflect light from the outer surface of the aircraft cabin wall to the camera; when the angle B is equal to 45°, the reflector (5) can reflect light parallel to the aircraft cabin wall (1) to the camera; when B is greater than 45°, the reflector (5) can reflect light from the external environment of the aircraft to the camera.

9. A high-speed aircraft exterior camera thermal protection device according to claim 6, characterized in that: When the external components of the cabin are damaged due to the influence of a harsh environment, the built-in transparent glass (6) can prevent the hot air flow outside the aircraft cabin from entering the cabin, and the built-in transparent glass (6) performs the anti-heat insulation function.

10. A high-speed aircraft external camera thermal protection device according to claim 9, characterized in that: When the built-in transparent glass (6) is damaged, the camera bracket (7), the camera (9) and the camera sealing pad (10) can prevent the hot air flow outside the aircraft cabin from entering the cabin, and the camera bracket (7) assumes the anti-heat insulation function.

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