An airspeed measuring device with anti-icing function
By setting a heating belt in the total pressure chamber and static pressure chamber of the airspeed measuring device and combining it with a temperature relay, the automatic control heating function is realized, which solves the problem of traditional airspeed tubes being prone to freezing when flying at high altitudes, and improves measurement accuracy and flight safety.
Patent Information
- Application Number
- CN202411779992.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-12-05
- Publication Date
- 2025-04-08
AI Technical Summary
Traditional airspeed tubes are prone to freezing during high altitude, high cold, high humidity and winter flights, resulting in distortion of measurement data and affecting flight safety.
A spacespeed measuring device with heating function is designed. By setting a heating belt in the total pressure chamber and the static pressure chamber and combining it with a temperature relay, the heating function is automatically controlled to avoid unnecessary power consumption.
It effectively avoids icing or blockage of airspeed tubes, ensures measurement accuracy, reduces the power consumption of the aircraft, and improves the safety of high-altitude flight.
Smart Images
Figure CN119780456A_ABST
Abstract
Description
Technical Field
[0001] The invention belongs to the technical field of atmospheric data and relates to an airspeed measuring device with an anti-deicing function. Background Art
[0002] The atmospheric data system is used to measure the aircraft's airspeed, pressure altitude and other parameters. The safety and reliability of the atmospheric data system are closely related to the accuracy and reliability of the operation of each aircraft system, and is an important system that affects flight safety. In the field of atmospheric data, traditional pitot tubes do not have a heating function. In high-altitude, cold, humid and winter flight conditions, the pitot tube is prone to ice, causing ice or water ingress in the pitot tube's pressure sensing area, resulting in distortion of total pressure and static pressure measurement data, affecting the measurement of the aircraft's airspeed and affecting flight safety. Summary of the invention
[0003] Purpose of the invention: To provide an airspeed measuring device with anti-deicing function. The airspeed measuring device has a heating function, which can prevent the pitot tube from freezing or clogging, ensure the accuracy of the measurement, avoid pitot tube failure, and ensure high-altitude flight safety. At the same time, a temperature relay is arranged inside the airspeed measuring device, which can disconnect the heating belt circuit when heating is not needed, thereby reducing the power consumption of the aircraft.
[0004] The technical solution of the present invention:
[0005] An airspeed measuring device with an anti-deicing function comprises: a housing, a base joint, a cavity cover, a total pressure conduit, a static pressure conduit, a total pressure cavity, a total pressure joint, a total pressure cavity heating belt, a static pressure cavity heating belt and a temperature relay;
[0006] The shell is hollow inside and has holes at both ends. One end of the shell is threadedly connected to the base joint, and the other end of the base joint is welded to the cavity cover.
[0007] The total pressure chamber and the total pressure joint are connected by heat-conducting adhesive and are arranged in the shell; the total pressure chamber is a hollow cylinder; a through hole is arranged inside the total pressure joint, and a static pressure chamber and a groove are arranged on the outer wall; the temperature relay is installed in the groove;
[0008] The total pressure conduit passes through the internal through hole of the total pressure joint and extends into the total pressure cavity; the static pressure conduit passes through the total pressure joint and extends into the static pressure cavity; the total pressure conduit and the static pressure conduit are welded and fixed to the cavity cover;
[0009] A total pressure chamber heating belt is arranged between the total pressure chamber and the shell;
[0010] A static pressure chamber heating belt is arranged between the total pressure joint and the shell.
[0011] Furthermore, the total pressure chamber heating belt, the static pressure chamber heating belt and the temperature relay wire pass through the internal through hole of the total pressure joint and the wire groove of the cavity cover.
[0012] Further, the total pressure chamber heating belt and the static pressure chamber heating belt are connected in parallel and then connected in series with the temperature relay, the temperature relay is connected to one end of the power supply, and the total pressure chamber heating belt and the static pressure chamber heating belt are respectively connected to the other end of the power supply;
[0013] When the temperature exceeds the action temperature, the temperature relay is disconnected, and the total pressure chamber heating belt and the static pressure chamber heating belt stop heating;
[0014] The temperature relay closes when the temperature is lower than the reset temperature, and the total pressure chamber heating belt and the static pressure chamber heating belt begin to heat.
[0015] Furthermore, the end of the total pressure conduit extending into the total pressure chamber is not arranged on the axis, and the distance from the inner wall of the total pressure chamber is 15% of the inner diameter of the total pressure chamber, so as to be as close as possible to the total pressure chamber heating belt 8 to avoid the total pressure conduit 4 from freezing and affecting the total pressure measurement.
[0016] Furthermore, 10 static pressure holes are arranged in the area of the shell facing the static pressure chamber, of which 6 static pressure holes are located at the top and 4 static pressure holes are located at the bottom.
[0017] Furthermore, a drainage hole is provided below the shell area corresponding to one end of the total pressure chamber close to the total pressure joint, and the diameter of the drainage hole is 0.5mm. That is, it can effectively drain the rainwater entering the total pressure chamber, and can also keep the total pressure chamber under pressure without affecting the measurement of the total pressure; the drainage hole is located at the bottom of the total pressure chamber, ensuring that the rainwater can be drained as much as possible without forming water accumulation in the total pressure chamber.
[0018] Furthermore, the distance between the static pressure hole and the total pressure hole at the front end of the shell is 6 times the shell diameter, thereby reducing the influence of the pitot tube shape and the aircraft angle of attack on the static pressure and improving the accuracy of the static pressure measurement.
[0019] Furthermore, the power density of the total pressure chamber heating belt increases near the total pressure inlet area of the shell, where the power density is the largest. Therefore, it is located in the front windward part of the airspeed measuring device and is prone to ice. The power density of the static pressure chamber heating belt increases near the static pressure hole. The power density is increased to prevent the static pressure hole from being blocked by ice and affecting the static pressure measurement.
[0020] Furthermore, a hollow area is provided in the total pressure chamber heating zone for drainage; and a hollow area is provided in the static pressure chamber heating zone for avoiding the static pressure hole.
[0021] Furthermore, the operating temperature is 80°C ± 3°C, and the reset temperature is 55°C ± 3°C. When the temperature of the airspeed measuring device reaches the operating temperature of 80±3°C, the temperature relay is disconnected, the internal circuit of the airspeed measuring device is disconnected, and the total pressure chamber heating belt 8 and the static pressure chamber heating belt 9 stop heating. When the temperature of the airspeed measuring device returns to the reset temperature of 55±3°C, the temperature relay is reset, the internal circuit of the airspeed measuring device is restored, and the total pressure chamber heating belt 8 and the static pressure chamber heating belt 9 continue to heat.
[0022] Beneficial Effects
[0023] The present invention adds a total pressure chamber heating belt and a static pressure chamber heating belt to the traditional airspeed measuring device, which can effectively prevent the airspeed measuring device from freezing or clogging and ensure the accuracy of the measurement. In addition, a temperature relay is installed inside the airspeed measuring device to reduce the power consumption of the aircraft. The present invention has a compact structure, low cost, reliable control, and high practical application value. BRIEF DESCRIPTION OF THE DRAWINGS
[0024] Figure 1 It is a schematic diagram showing the external upper part of the airspeed measuring device.
[0025] Figure 2 It is a schematic diagram showing the lower exterior of the airspeed measuring device.
[0026] Figure 3 This is a schematic diagram showing the internal structure of the airspeed measuring device after the heating belt is hidden.
[0027] Figure 4 It is a schematic diagram showing the assembly of the heating belt of the airspeed measuring device.
[0028] Figure 5 It is a schematic diagram showing the assembly of the temperature relay of the airspeed measuring device.
[0029] Figure 6 It is a schematic diagram showing the expansion of the total pressure chamber heating zone.
[0030] Figure 7 It is a schematic diagram showing the expansion of the static pressure chamber heating zone. DETAILED DESCRIPTION
[0031] The specific implementation of the present invention is further described below in conjunction with the accompanying drawings.
[0032] See also Figures 1 to 5 The schematic diagram of the structure of the present airspeed measuring device is shown in . It includes a housing 1, a base joint 2, a chamber cover 3, a total pressure conduit 4, a static pressure conduit 5, a total pressure chamber 6, a total pressure joint 7, a total pressure chamber heating belt 8, a static pressure chamber heating belt 9 and a temperature relay 10; the base joint 2 and the chamber cover 3 are connected by laser welding; the housing 1 and the base joint 2 are connected by threads; the total pressure conduit 4 and the static pressure conduit 5 are welded to the chamber cover 3 by flame brazing; the total pressure chamber 6 and the total pressure joint 7 are connected by thermal conductive adhesive; the total pressure chamber heating belt 8 is bonded to the outer surface of the total pressure chamber 6 by thermal conductive adhesive, and is bonded to the inner wall of the housing 1 by thermal conductive adhesive; the static pressure chamber heating belt 9 is bonded to the outer surface of the total pressure joint 7 by thermal conductive adhesive, and is bonded to the inner wall of the housing 1 by thermal conductive adhesive; the temperature relay 10 is bonded to the groove of the total pressure joint 7 by thermal conductive adhesive; the wires of the total pressure chamber heating belt 8, the static pressure chamber heating belt 9 and the temperature relay 10 pass through the wire grooves of the total pressure joint 7 and the chamber cover 3.
[0033] A wire threading groove is designed inside the total pressure joint 7, and the wires of the total pressure chamber heating belt 8, the static pressure chamber heating belt 9 and the temperature relay 10 are passed through the wire threading groove. A static pressure cavity is arranged on the surface of the total pressure joint 7, and the static pressure cavity is connected to the static pressure conduit 5.
[0034] The total pressure conduit 4 passes through the interior of the total pressure joint 7 and extends into the total pressure chamber. At the same time, the total pressure conduit 4 is placed offset, close to the inner wall of the total pressure chamber 6, and the distance from the inner wall of the total pressure chamber 6 is 1.2 mm, so that it can be as close to the total pressure chamber heating belt 8 as possible to avoid ice formation on the total pressure conduit 4 and affect the total pressure measurement.
[0035] The internal circuit connection mode of the airspeed measuring device is that the total pressure chamber heating belt 8 and the static pressure chamber heating belt 9 are connected in parallel, and then connected in series with the temperature relay 10. And by using +28VDC power supply, the positive and negative poles are not distinguished, and the power consumption is 36W. At normal temperature, the temperature relay 10 remains in a normally closed state, and the resistance of the temperature relay 10 is close to 0Ω. When the temperature of the airspeed measuring device reaches the operating temperature of 80±3℃, the temperature relay is disconnected, the internal circuit of the airspeed measuring device is disconnected, and the total pressure chamber heating belt 8 and the static pressure chamber heating belt 9 stop heating. When the temperature of the airspeed measuring device returns to the reset temperature of 55±3℃, the temperature relay is reset, the internal circuit of the airspeed measuring device is restored, and the total pressure chamber heating belt 8 and the static pressure chamber heating belt 9 continue to heat.
[0036] The shell 1 of the airspeed measuring device is drilled with drainage holes and static pressure holes. The diameter of the drainage hole is 0.5mm, which can effectively drain the rainwater entering the total pressure chamber and keep the total pressure chamber under pressure without affecting the measurement of the total pressure; the drainage hole is located at the bottom of the total pressure chamber to ensure that the rainwater can be drained as much as possible and no water will accumulate in the total pressure chamber. The shell 1 of the airspeed measuring device has a diameter of 15mm, and the distance between the static pressure hole and the front total pressure port is 90mm, which is 6 times the diameter of the shell 1, reducing the influence of the static pressure on the shape of the pitot tube and the aircraft angle of attack, and improving the accuracy of static pressure measurement.
[0037] Rectangular hollow areas 801 and 901 are reserved on the total pressure chamber heating belt 8 and the static pressure chamber heating belt 9, respectively. The hollow area 801 on the total pressure chamber heating belt 8 is reserved for drainage, and its length is 3mm and its width is 2mm; the hollow area 901 on the static pressure chamber heating belt 9 is reserved for sensing static pressure, and the hollow areas correspond to the upper and lower static pressure hole positions, respectively. The length of the hollow area corresponding to the upper static pressure hole position is 9.5mm and the width is 2mm, and the length of the hollow area corresponding to the upper static pressure hole position is 7mm and the width is 2mm.
[0038] The resistance value of the total pressure chamber heating belt 8 is 31Ω±2Ω, and the resistance value of the static pressure chamber heating belt 9 is 71Ω±2Ω. The power density is increased in the local areas 802 and 902 of the total pressure chamber heating belt 8 and the static pressure chamber heating belt 9. In the area 802 at one end of the total pressure chamber heating belt 8 close to the total pressure port of the airspeed measuring device, the resistance is locally increased within a range of 9.5mm in length. The local resistance of this area is 19Ω±1Ω. The power density here is the largest, so it is located in the front windward part of the airspeed measuring device and is prone to ice. In the area 902 close to the static pressure hole on the static pressure chamber heating belt 9, the resistance is locally increased within a range of 2.5mm in axial length along both ends with the static pressure hole as the center. The local resistance of this area is 39Ω±1Ω, which improves the power density to prevent the static pressure hole from being blocked by ice and affecting the static pressure measurement.
[0039] Lead wires are led out from respective welding point positions 803 and 903 on the total pressure chamber heating belt 8 and the static pressure chamber heating belt 9 .
Claims
1. An airspeed measuring device with anti-icing function, characterized in that: The device comprises: a shell, a base joint, a cavity cover, a total pressure conduit, a static pressure conduit, a total pressure cavity, a total pressure joint, a total pressure cavity heating belt, a static pressure cavity heating belt and a temperature relay; The shell is hollow inside and has holes at both ends. One end of the shell is threadedly connected to the base joint, and the other end of the base joint is welded to the cavity cover. The total pressure chamber and the total pressure joint are connected by heat-conducting adhesive and are arranged in the shell; the total pressure chamber is a hollow cylinder; a through hole is arranged inside the total pressure joint, and a static pressure chamber and a groove are arranged on the outer wall; the temperature relay is installed in the groove; The total pressure conduit passes through the internal through hole of the total pressure joint and extends into the total pressure cavity; the static pressure conduit passes through the total pressure joint and extends into the static pressure cavity; the total pressure conduit and the static pressure conduit are welded and fixed to the cavity cover; A total pressure chamber heating belt is arranged between the total pressure chamber and the shell; A static pressure chamber heating belt is arranged between the total pressure joint and the shell.
2. The airspeed measuring device according to claim 1, characterized in that: The heating belt of the total pressure chamber, the heating belt of the static pressure chamber and the wires of the temperature relay pass through the internal through hole of the total pressure joint and the wire groove of the chamber cover.
3. The airspeed measuring device according to claim 2, characterized in that: The total pressure chamber heating belt and the static pressure chamber heating belt are connected in parallel and then connected in series with the temperature relay. The temperature relay is connected to one end of the power supply, and the total pressure chamber heating belt and the static pressure chamber heating belt are respectively connected to the other end of the power supply. When the temperature exceeds the action temperature, the temperature relay is disconnected, and the total pressure chamber heating belt and the static pressure chamber heating belt stop heating; The temperature relay closes when the temperature is lower than the reset temperature, and the total pressure chamber heating belt and the static pressure chamber heating belt begin to heat.
4. The airspeed measuring device according to claim 3, characterized in that: One end of the total pressure conduit extending into the total pressure chamber is not arranged on the axis, and the distance from the inner wall of the total pressure chamber is 15% of the inner diameter of the total pressure chamber.
5. The airspeed measuring device according to claim 4, characterized in that: Ten static pressure holes are arranged in the area of the shell facing the static pressure cavity, of which six are located at the top and four are located at the bottom.
6. The airspeed measuring device according to claim 5, characterized in that: A drainage hole is provided below the shell area corresponding to one end of the total pressure chamber close to the total pressure joint, and the diameter of the drainage hole is 0.5 mm.
7. The airspeed measuring device according to claim 6, characterized in that: The distance between the static pressure hole and the total pressure hole at the front end of the shell is 6 times the diameter of the shell.
8. The airspeed measuring device according to claim 7, characterized in that: The power density of the total pressure chamber heating zone increases near the total pressure inlet of the shell; the power density of the static pressure chamber heating zone increases near the static pressure hole.
9. The airspeed measuring device according to claim 8, characterized in that: A hollow area is provided in the total pressure chamber heating zone for drainage; a hollow area is provided in the static pressure chamber heating zone for avoiding the static pressure hole.
10. The airspeed measuring device according to claim 9, characterized in that: The operating temperature is 80℃±3℃ and the reset temperature is 55℃±3℃.