Angle of attack sensor vane with heating function

Abstract

The utility model relates to measuring equipment, concerns the improvement of the weather vane of the angle of attack sensor (hereinafter also referred to as the weather vane) and can be used to determine the parameters of the movement of aircraft relative to the air environment.The essence is a weather vane of an angle of attack sensor with a heating function, made of an AMg alloy, consisting of a base and an aerodynamic housing attached to it, wherein the base is made in the form of a truncated cone, wherein in the base there are two fastening holes with the possibility of fastening to the angle of attack sensor; the housing is made in a cross-section of an aerodynamic shape and is connected to the angle of attack sensor by wires, characterized in that in the housing there are two blind cylindrical holes, in the first of which at least one thermistor is placed, in the second - a heating element of cylindrical shape, wherein the remaining free space of the cylindrical holes is filled with a heat-conducting compound, wherein the thermistors and the heating element are connected by a wire. 3 fig.

Description

[0001] The utility model relates to measuring equipment, concerns the improvement of the weather vane of the angle of attack sensor (hereinafter also referred to as the weather vane) and can be used to determine the parameters of the movement of aircraft relative to the air environment.

[0002] This utility model was developed to address the problem of improving the performance of angle-of-attack sensor vanes. These issues are caused by insufficient thermal conductivity and reliability.

[0003] From the studied level of technology, an analogue was identified [https: / / studfile.net / preview / 9069388 / ], a weather vane-type angle of attack sensor with a weather vane, the heating of which is provided by a simple resistive heater operating according to an on-off circuit.

[0004] The disadvantage of the known technical solution is that it does not control the temperature of the heating element and, as a result, it can overheat under certain usage scenarios, which, in turn, reduces the reliability and overall mean time between failures of the product.

[0005] The closest in purpose and design, chosen by the applicant as a prototype, is the invention according to patent US 4121088 A "Device for a data sensor with electrically heated air", the essence of which is a device for a data sensor with electrically heated air, made, among other things, from an Amg alloy, consisting of a base and an aerodynamic housing attached to it, wherein the base is made in the form of a truncated cone, wherein in the base there are two mounting holes with the possibility of attaching to an angle of attack sensor; the housing is made in a cross-section of an aerodynamic shape and is connected by wires to the angle of attack sensor, containing a heating element consisting of an assembly of materials with a positive temperature coefficient, fastened together with a perforated tape, which is also the main heating element.In this case, a rectangular groove is made in the housing, in which a heating assembly filled with a heat-resistant compound is placed.

[0006] The disadvantage of the prototype is:

[0007] insufficient thermal conductivity between the housing and the heating element due to the heating element being made in the form of a parallelepiped compared to a cylindrical one in the stated technical solution, which, firstly, negatively affects heat transfer, and secondly, a thicker layer of compound is used, which also negatively affects heat transfer;

[0008] Insufficient reliability due to the absence of the first cylindrical hole in the housing with the ability to place thermistors in it and connect the thermistors to the heating element with a wire to protect against overheating, which in turn complicates the design and requires the use of a high-precision method of fastening the perforated tape to the heating material, and also leads to less uniform heat distribution and, accordingly, reduces the overall time between failures.

[0009] The technical problem solved by the claimed utility model and its technical result is an increase in operational characteristics, namely:

[0010] improving the thermal conductivity between the housing and the heating element by making a second cylindrical hole in the housing, in which a cylindrical heating element is placed, while the cylindrical shape of the heating element allows to reduce the gap between it and the housing, which, firstly, has a positive effect on heat transfer, and secondly, allows the use of a thinner layer of compound, which also has a positive effect on heat transfer;

[0011] Improved reliability due to the absence of overheating by creating a first cylindrical hole in the housing for accommodating thermistors and connecting the thermistors to the heating element with a wire for overheat protection. This reduces excessive heating of the heating element and quickly transfers heat to the vane housing, resulting in uniform heat distribution and, consequently, an increase in the overall mean time between failures, as the likelihood of heater failure is reduced.

[0012] The essence of the claimed technical solution is a weather vane of an angle of attack sensor with a heating function, made of an AMg alloy, consisting of a base and an aerodynamic housing attached to it, wherein the base is made in the form of a truncated cone, wherein two mounting holes are made in the base with the possibility of attaching to the angle of attack sensor; the housing is made in a section of an aerodynamic shape and is connected to the angle of attack sensor by wires, characterized in that two cylindrical holes are made in the housing, in the first of which at least one thermistor is placed, in the second - a cylindrical heating element, while the remaining free space of the cylindrical holes is filled with a heat-conducting compound, and the thermistors and the heating element are connected by a wire.

[0013] The claimed technical solution is illustrated in Fig. 1-3.

[0014] Figure 1 shows a general view of the claimed weather vane.

[0015] Fig. 2 shows a bottom view of the claimed weather vane.

[0016] Fig. 3 shows a side view of the claimed weather vane.

[0017] The following are indicated by the positions in Fig.1-3:

[0018] 1 - base,

[0019] 2 - body,

[0020] 3 - mounting holes,

[0021] 4 - first cylindrical hole,

[0022] 5 - the second cylindrical hole,

[0023] 6 - thermistors,

[0024] 7 - heating element,

[0025] 8 - wires.

[0026] The following is a description of the claimed technical solution.

[0027] The stated technical result is achieved by a weather vane angle of attack sensor that supports a heating function, which is provided by two cylindrical elements installed inside the weather vane along its entire length, one of which is a heating element and provides only the heating function, and the second is a thermistor with a positive temperature coefficient and is used to protect against overheating.

[0028] The declared weather vane of the angle of attack sensor (Fig. 1-3) is made of AMg alloy and consists of

[0029] bases 1 and

[0030] attached to it aerodynamic body 2,

[0031] at the same time

[0032] base 1 completed

[0033] in the form of a truncated cone, with two mounting holes 3 made in the base with the possibility of attaching to an angle of attack sensor (not shown in the figure);

[0034] Body 2 completed

[0035] in the aerodynamic section (Fig. 2),

[0036] and connected to the angle of attack sensor by wires 8,

[0037] two blind cylindrical openings 4 and 5 are made in the housing 2, in the first cylindrical opening 4 at least one thermistor 6 is placed, in the second 5 - a cylindrical heating element 7, while the remaining free space of the cylindrical openings 4 and 5 is filled with a heat-conducting compound (not indicated in the figure),

[0038] the thermistors 6 and the heating element 7 are connected by a wire (not shown in the figure).

[0039] The following is an example of the implementation of the claimed technical solution.

[0040] The declared weather vane is manufactured, for example, by milling. All elements of the declared weather vane are connected to each other by assembly operations, such as welding, gluing, etc.

[0041] The weather vane is manufactured in an aerodynamic section (Fig. 2), pointed on one side, which improves operational characteristics - streamlining by air masses is improved, which provides better stability in the readings of the angle of attack sensor.

[0042] The declared weather vane is installed on the aircraft angle of attack sensor, attached, for example, by a bolted connection through mounting holes 3.

[0043] The weather vane body is rigidly connected to the base, for example, turned into a single piece.

[0044] Cylindrical holes 4 and 5 are drilled inside the housing. At least one thermistor 6 is installed in the first cylindrical hole 4, and a cylindrical heating element 7 is installed in the second hole 5. Thermistors 6 can be a single thermistor or an assembly of several thermistors connected in series.

[0045] The number of thermistors may be, for example, from 1 to 40 or more, and the applicant has established that in any of the specified particular cases of implementation the declared technical result is achieved.

[0046] Then the remaining free space of cylindrical holes 4 and 5 is filled with heat-conducting compound so that no voids remain.

[0047] The cylindrical shape of the heating element 7 has made it possible to reduce the gap between it and the housing 2, from which a logical conclusion follows about the improvement of thermal conductivity due to both a smaller gap and a thinner compound layer, which proves the achievement of the stated technical result.

[0048] The electrical terminal of the heating element 7 is connected to the terminal of the thermistors 6.

[0049] The two remaining electrical terminals, one each for heating element 7 and thermistors 6, are extended with flexible wire 8 using welding. These wires are then connected to the angle-of-attack sensor connectors, which are responsible for the heating function.

[0050] When the aircraft is moving, the heating element 7 heats the weather vane, which prevents icing.

[0051] When a critically high temperature is reached, the thermistors 6 stop the temperature from rising, preventing excessive overheating of the weather vane, the heat of which can be transferred inside the angle of attack sensor, which proves the achievement of the stated technical result - improved reliability.

[0052] Thus, from the above, it can be concluded that the applicant has solved the identified technical problem and achieved the stated technical result: improved performance characteristics, namely:

[0053] The thermal conductivity between the housing and the heating element has been improved by making a second cylindrical hole in the housing, in which a cylindrical heating element is placed. The cylindrical shape of the heating element allows for a smaller gap between it and the housing, which, firstly, has a positive effect on heat transfer, and secondly, allows for the use of a thinner layer of compound, which also has a positive effect on heat transfer;

[0054] Improved reliability due to the absence of overheating by creating a first cylindrical hole in the housing for accommodating thermistors and connecting the thermistors to the heating element with a wire for overheat protection. This reduces excessive heating of the heating element and quickly transfers heat to the vane housing, resulting in uniform heat distribution and, consequently, an increased overall MTBF, as the likelihood of heater failure is reduced.

Claims

A vane of an angle of attack sensor with a heating function, made of an AMg alloy, consisting of a base and an aerodynamic housing attached thereto, wherein the base is made in the form of a truncated cone, wherein two fastening holes are made in the base with the possibility of fastening to the angle of attack sensor; the housing is made in a cross-section of an aerodynamic shape and is connected to the angle of attack sensor by wires, characterized in that two blind cylindrical holes are made in the housing, in the first of which at least one thermistor is placed, in the second - a cylindrical heating element, wherein the remaining free space of the cylindrical holes is filled with a heat-conducting compound, wherein the thermistors and the heating element are connected by a wire.

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