An aircraft windshield terminal block and method of detecting moisture

Abstract

The application provides an aircraft windshield terminal junction box and a method for detecting humidity, and belongs to the field of aviation equipment. The aircraft windshield terminal junction box is installed on an aircraft windshield; the terminal junction box comprises a shell, a humidity sensor and a temperature control plug; the temperature control plug is in communication with the shell; a plurality of wiring terminals are arranged in the temperature control plug; and the humidity sensor is connected with the temperature control plug. The application can timely detect the water inflow in or near the terminal junction box and timely feedback to a control system (WHC), thereby reducing the flight risk.

Description

Technical Field

[0001] This invention belongs to the field of aviation equipment, specifically relating to an aircraft windshield terminal junction box and a method for detecting humidity. Background Technology

[0002] Currently, aircraft windshield anti-icing and defogging systems include a heating film, a power supply system, and a temperature monitoring system. Power from the engine is transmitted to the heating film via a terminal plug and power cables. The inner side of the outermost impact-resistant layer of the windshield is coated with a heating film. When electricity is applied to both ends of the heating film, it generates heat to prevent icing and fogging. Temperature monitoring devices are located on one side of the heating film. Continuous heating of the heating film can cause overheating, aging, or decomposition of the inner filling layer of the windshield. Therefore, when the temperature monitoring device detects high temperatures, it connects to the windshield heating control computer (WHC) via cables from the terminal junction box. Based on the temperature signal, the WHC shuts off the heating system to prevent the continuous generation of high temperatures.

[0003] The terminal junction box is a key component of the windshield heating and control system, serving as the common interface between the power supply and temperature control systems. Furthermore, when a windshield malfunction is suspected or detected, the resistance and impedance of the windshield heating and temperature control systems need to be tested through the terminal junction box.

[0004] However, when water accumulates in the sealing silicone around the windshield, the terminal junction box can easily become a water reservoir, creating a localized water-damped environment. If the windshield heating wires are worn or the connection points of the heating wires are submerged in water, an electric arc can easily occur. Currently, most mainstream windshield heating control systems lack arc detection capabilities. Water ingress into the junction box is a prerequisite for arcing or short circuits; therefore, waterproofing or timely detection of water ingress is a crucial step for safe windshield operation.

[0005] Currently, there is no good method or means to detect wire wear, especially water ingress into the junction box. Water accumulation in the junction box is a major cause of windshield heating system malfunctions and localized high temperatures and arcing in the wires. If an arc occurs in a critical location, it can cause the structural glass layer of the windshield to shatter, and in severe cases, the windshield can be detached, putting the pilot in an extremely dangerous situation. Summary of the Invention

[0006] The purpose of this invention is to solve the problems existing in the prior art and provide an aircraft windshield terminal junction box and a method for detecting humidity, so as to detect water ingress into the junction box in a timely manner and provide timely feedback to the control system (WHC), thereby reducing the risk.

[0007] This invention is achieved through the following technical solution:

[0008] In a first aspect, the present invention provides an aircraft windshield terminal junction box, the terminal junction box being installed on the aircraft windshield; the terminal junction box includes: a housing, a humidity sensor, and a temperature control plug;

[0009] The temperature control plug is connected to the housing;

[0010] The temperature control plug is equipped with multiple wiring terminals;

[0011] The humidity sensor is connected to the temperature control plug.

[0012] A further improvement of the present invention is that:

[0013] The humidity sensor is a resistive lithium oxide hygrometer, a dew point lithium chloride hygrometer, a carbon humidity-sensitive element, an alumina humidity-sensitive sensor, or a ceramic humidity sensor.

[0014] A further improvement of the present invention is that:

[0015] The housing is an L-shaped structure with a rear opening, and the rear opening of the housing is bonded to the windshield.

[0016] An opening is provided at the left end of the housing as a lead wire outlet, and the temperature control plug is connected to its right end.

[0017] The wiring terminals inside the temperature control plug include: multiple heating wire terminals, multiple temperature measuring wire terminals, and multiple unused wiring terminals.

[0018] A further improvement of the present invention is that:

[0019] The humidity sensor includes a sensor substrate and two humidity acquisition wires connected to both ends of the sensor substrate.

[0020] The other ends of the two humidity acquisition wires are connected to the unused terminals in the temperature control plug.

[0021] A further improvement of the present invention is that:

[0022] The other end of the power supply wire connected to the aircraft windshield passes through the lead-out end of the wire into the inner cavity of the housing and connects to the heating wire terminal inside the temperature control connector.

[0023] The other end of the temperature control wire connected to the aircraft windshield passes through the lead-out end of the wire into the inner cavity of the housing and is connected to the temperature measuring wire terminal inside the temperature control connector.

[0024] The sensor substrate is disposed between the power supply wire, the temperature control wire, and the side wall of the housing;

[0025] The length of the sensor substrate of the humidity sensor is greater than the width of all temperature control wires and power supply wires arranged together.

[0026] A further improvement of the present invention is that:

[0027] The sensor base plate of the humidity sensor is located at the connection between the housing and the temperature control connector.

[0028] A further improvement of the present invention is that:

[0029] The sensor substrate of the humidity sensor is located at the sealing silicone at the bottom of the windshield, and the other ends of the two humidity acquisition wires are inserted into the inner cavity of the housing from the wire lead-out end and connected to the temperature control connector.

[0030] A further improvement of the present invention is that:

[0031] The humidity sensing wire is made of copper braided wire with a tin-plated layer, and an insulating sleeve made of insulating plastic is installed on the outside of the wire.

[0032] Furthermore, a temperature sensor is installed inside the housing, and the temperature acquisition wire of the temperature sensor is connected to an unused terminal block.

[0033] In a second aspect, the present invention provides a humidity detection method, wherein a humidity sensor is installed in the terminal junction box of an aircraft windshield or at the sealing silicone at the bottom of the aircraft windshield, and the humidity is collected by the humidity sensor. Then, it is determined whether the humidity exceeds a set threshold. If so, the method prompts the replacement of the aircraft windshield.

[0034] Compared with the prior art, the beneficial effects of the present invention are: the present invention can detect water ingress in or near the terminal junction box in a timely manner and can provide timely feedback to the control system (WHC), thereby reducing flight risks. Attached Figure Description

[0035] Figure 1 This is a schematic diagram of the wiring terminals on an existing temperature control connector;

[0036] Figure 2 A schematic diagram showing the typical installation method of existing windshield terminal junction boxes;

[0037] Figure 3-1 A schematic diagram of the wire lead-out end of the existing windshield terminal junction box;

[0038] Figure 3-2 A schematic diagram showing the route by which moisture enters the housing of the terminal junction box;

[0039] Figure 4 Recommended installation location for the humidity sensor;

[0040] Figure 5 This is a schematic diagram of the structure after the existing windshield junction box has been removed.

[0041] Figure 6-1 This is a bottom view of the terminal junction box of the present invention.

[0042] Figure 6-2 This is a side view of the junction box of the present invention.

[0043] Figure 7 This is a schematic diagram of the structure of the wire lead-out end of the terminal junction box of the present invention;

[0044] Figure 8 This is a functional structure distribution diagram of the terminal junction box of the present invention. Detailed Implementation

[0045] The present invention will now be described in further detail with reference to the accompanying drawings:

[0046] To detect water accumulation inside terminal junction boxes, this invention incorporates a humidity sensor within the junction box. Using a WHC (Water Humidity Control Center) or an external detection circuit, humidity information is read, enabling automatic or proactive detection of moisture levels inside the junction box. Upon detection of water ingress, damaged glass is promptly replaced, providing technical support for ensuring flight safety.

[0047] like Figure 2 , Figure 6-1 and Figure 6-2 As shown, the existing windshield terminal junction box includes a housing 301 and a temperature control plug 1. The housing 301 is an L-shaped housing structure with an opening on the rear side. An opening is provided at its left end as a wire lead-out end, and a temperature control plug 1 is connected to its right end. The temperature control plug 1 is connected to the housing 301.

[0048] During installation, the edge of the rear opening of the housing 301 is bonded to the inside of the windshield 201 by adhesive bonding. Figure 2 In the embodiment shown, the temperature control plug 1 is located at the lower right end of the housing 301. In other models of windshield terminal junction boxes, the temperature control plug 1 is located in the middle of the housing. The direction of the temperature control plug 1 is perpendicular to the glass and faces the cockpit side.

[0049] The existing layout of the wiring terminals on the temperature control plug 1 is as follows Figure 1 As shown, Figure 1 In the diagram, the black circular terminals are the currently used wiring terminals, specifically including: 2-3 heating wire terminals (power supply terminals) 101, indicated by large black circles, and 6-8 temperature sensing wire terminals 102, indicated by small black circles. There are also some other unused terminals. Figure 1 The blank ring in the diagram represents an unused terminal block.

[0050] Figure 1 The embodiment shown is just one way of arranging terminals in existing junction boxes. This method is used for a certain type of aircraft (e.g., ARJ21). Other aircraft may use different forms of terminal arrangement for their temperature control plugs, but they all have the following characteristics: there are 2-4 power supply terminals, 4-8 temperature sensing wire terminals, and some unused terminals.

[0051] This invention utilizes these unused terminals on the temperature control plug 1 to increase the humidity monitoring function inside the terminal junction box.

[0052] Specifically, a humidity sensor is installed inside the terminal junction box. The humidity sensor's humidity acquisition wire is connected to an unused terminal. Real-time analysis and detection of the humidity inside the terminal junction box can be achieved through an existing external windshield heating control computer (WHC) or an external detection circuit.

[0053] This invention allows for the connection of a humidity sensor to unused terminals without altering the layout of existing terminal boxes.

[0054] Figure 3-1 This is a schematic diagram of the wire lead-out terminals in an existing windshield junction box. The rear opening of the housing 301 is glued to the glass 201. The lead-out wires include 2-3 power supply wires 103 and 6-8 temperature control wires 104 (the temperature control wires are connected to the heating film on the inner side of the outer layer of the windshield glass to control the glass temperature; generally, there are 4-8 wires, divided into 2-4 groups, forming a circuit to monitor the temperature of the heating film). All lead-out wires are arranged sequentially from top to bottom, and all wires pass through... Figure 3-1 The wires, as shown, pass through the edge of the windshield and enter the interior of housing 301 via the terminal junction box, connecting to the terminals in the temperature control plug. Specifically, the power supply wire 103 connects to the heating wire terminal 101, and the temperature control wire 104 connects to the temperature measuring wire terminal 102. Both types of leads (power supply and temperature control wires) are tin-plated copper braided wires, and each is surrounded by an insulating sleeve made of insulating plastic (polytetrafluoroethylene).

[0055] Figure 5 This is a structural diagram of the existing windshield junction box after it has been removed. The view is from the rear opening of the housing towards the front. Figure 5 The power supply wire 103 and the temperature control wire 104 are both connected to the terminal block inside the terminal box.

[0056] The humidity sensor used in this invention can be one of the following existing humidity sensors:

[0057] Resistive lithium oxide hygrometers, dew point lithium chloride hygrometers, carbon humidity sensors, alumina humidity sensors, or ceramic humidity sensors, etc.

[0058] Preferably, the humidity sensor is an alumina humidity sensor, mainly because the alumina humidity sensor element is small in size and easy to install inside the junction box. At the same time, it has high sensitivity, which makes it convenient for WHC to collect information inside the junction box in real time or to connect other instruments and equipment to the junction box after flight to realize humidity sampling detection.

[0059] The humidity sensor can be installed anywhere inside the junction box, such as at the cable inlet or at the bottom of the housing.

[0060] Preferred, such as Figure 4 As shown, the humidity sensor is installed between the power supply wire, the temperature control wire, and the side wall of the housing, or it can be installed at the connection between the housing and the temperature control connector. The reason is as follows:

[0061] first, Figure 3-1 The location shown is the lead-out end of the wire. Typically, a moisture channel exists between the sealing silicone around the wiring and the windshield. Moisture will travel along the wires (including power supply wires and temperature control wires) and enter the inner cavity of the housing through the opening on the left side. The moisture entry route is as follows... Figure 3-2 As shown by the dashed line in the diagram. Therefore, the first recommended location for installing the humidity sensor is between the lead wire and the side wall of the housing.

[0062] Secondly, when moisture enters the inner cavity of the housing, it tends to remain inside the temperature control plug. According to regulations, for conductivity purposes, a small section of the wire at the connection point between the terminal block and the conductor must be exposed, forming a clearance (generally 0.5-0.8mm). This exposed section of wire is prone to arcing when it encounters moisture. Therefore, the second recommended installation location for the humidity sensor is on the back of the temperature control plug, specifically at the connection point between the plug and the housing.

[0063] The humidity sensor is installed as follows:

[0064] Humidity sensors are typically in the form of sheets or needles, with sheet-shaped alumina humidity sensors being preferred. For example... Figure 4 As shown, the sheet-like alumina humidity sensor includes: a sensor substrate 501 and two humidity acquisition wires 502. The sensor substrate 501 is an aluminum substrate sheet, that is, a rectangular aluminum plate. The humidity acquisition wires 502 can be connected to the sensor substrate 501 in various existing methods. The preferred construction method is to use laser welding process to weld the lead wires of the humidity sensor to both ends of the sensor substrate 501.

[0065] One end of each humidity sensing wire is connected to the aluminum substrate, and the other end is connected to an unused terminal on the temperature control plug (the temperature control plug for windshields of all aircraft types has spare terminals that can be used to expand functionality). It is recommended to use the same material as the windshield temperature sensor wires—tinned copper braided wire. This type of wire has low resistivity and strong resistance to bending damage. Other wires are also acceptable.

[0066] Preferably, the length of the sensor substrate 501 of the humidity sensor is greater than the width of all temperature control wires and power supply wires after they are arranged, so that water vapor entering along each wire can be fully detected.

[0067] Figure 4 For the preferred installation location of the humidity sensor, the sensor substrate 501 and the humidity acquisition wire 502 are located inside the cavity of the housing 301, and the other end of the humidity acquisition wire 502 is connected to... Figure 1 Unused terminal blocks are connected.

[0068] Figure 7 This is a schematic diagram of the structure of the junction box wire lead-out end with humidity self-test function of the present invention. In the figure, the humidity sensor substrate 501 is located between the lead-out wire and the side wall of the junction box 301.

[0069] Figure 8 This is a functional structure diagram of the junction box with humidity self-testing function of the present invention. The humidity sensor is located inside the terminal junction box. Figure 8 The dew point probe in the text refers to a humidity sensor. It is used to detect water ingress into the terminal junction box. The windshield temperature control wire is connected to a temperature-sensing resistor on the glass to detect and control the windshield's heating. The power supply wire is connected to the busbars on both sides of the windshield, and the charge is connected to the heating film through the busbars to achieve automatic windshield heating control.

[0070] Furthermore, a temperature sensor can be installed inside the terminal junction box. Connecting the temperature sensor's acquisition wire to an unused terminal allows for temperature monitoring within the junction box. During post-flight inspection, simply connecting the external device to the temperature control plug allows the humidity and temperature information inside the casing to be read using the humidity and temperature sensors, significantly improving system safety.

[0071] To avoid obstructing the view, the housing of the terminal junction box is usually installed near the lower left or lower right corner of the windshield. These corners are precisely where moisture tends to accumulate. To move the humidity detection point forward, the humidity sensor can be placed near the sealing silicone at the lower left or lower right corner, closest to the housing. Specifically, when sealing the windshield with silicone, the humidity sensor's substrate is directly adhered to the silicone. Then, the other end of the humidity acquisition wire is led out from the wire outlet on the housing and inserted into the inner cavity of the housing, connecting to the temperature control connector. This way, when the silicone seal is no longer applied, moisture will accumulate at the lower left or lower right corner of the windshield. At this point, the moisture can come into contact with the sensor substrate, allowing the humidity sensor to detect the humidity. This allows for the detection of defects and potential problems earlier, before moisture enters the housing of the terminal junction box.

[0072] Furthermore, the present invention also provides a humidity detection method, which utilizes the aforementioned terminal junction box to detect the water accumulation inside the terminal junction box, or sets the humidity sensor at the sealing silicone at the bottom of the windshield, so as to facilitate the early detection of defects and potential hazards before water vapor enters the housing.

[0073] When water enters the junction box, it can cause arcing, and in severe cases, the windshield can crack or even detach, jeopardizing flight safety. This invention allows for the measurement of humidity inside or near the casing. Excessive humidity (exceeding a set threshold) can easily lead to corrosion and cracking of the temperature control wires. Therefore, upon detecting water ingress, it can alert personnel to replace the windshield promptly, preventing the use of faulty glass and thus ensuring flight safety.

[0074] In the description of this invention, it should be noted that, unless otherwise explicitly specified and limited, the terms "connected" and "linked" should be interpreted broadly. For example, they can refer to a fixed connection, a detachable connection, or an integral connection; they can refer to a mechanical connection or an electrical connection; they can refer to a direct connection or an indirect connection through an intermediate medium. Those skilled in the art can understand the specific meaning of the above terms in this invention according to the specific circumstances.

[0075] In the description of this invention, unless otherwise stated, the terms "upper," "lower," "left," "right," "inner," "outer," etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are used only for the convenience of describing this invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, or be constructed and operated in a specific orientation. Therefore, they should not be construed as limitations on this invention.

[0076] Finally, it should be noted that the above technical solution is only one embodiment of the present invention. For those skilled in the art, based on the application methods and principles disclosed in the present invention, it is easy to make various types of improvements or modifications, and not limited to the methods described in the above specific embodiments of the present invention. Therefore, the methods described above are only preferred and have no limiting significance.

Claims

1. A terminal junction box for an aircraft windshield, characterized in that: The terminal junction box is installed on the aircraft windshield; the terminal junction box includes: a housing, a humidity sensor, and a temperature control plug; The temperature control plug is connected to the housing; The temperature control plug is equipped with multiple wiring terminals; The humidity sensor is connected to the temperature control plug; The housing is an L-shaped structure with a rear opening, which is adhered to the windshield. An opening is provided at the left end of the housing as a lead wire outlet, and the temperature control plug is connected to its right end. The wiring terminals inside the temperature control plug include: multiple heating wire terminals, multiple temperature measuring wire terminals, and multiple unused wiring terminals. The humidity sensor includes a sensor substrate and two humidity acquisition wires connected to both ends of the sensor substrate; the other ends of the two humidity acquisition wires are connected to unused terminals in the temperature control plug. The other end of the power supply wire connected to the aircraft windshield passes through the lead-out end into the inner cavity of the housing and connects to the heating wire terminal in the temperature control connector; the other end of the temperature control wire connected to the aircraft windshield passes through the lead-out end into the inner cavity of the housing and connects to the temperature measuring wire terminal in the temperature control connector; the sensor substrate is disposed between the power supply wire, the temperature control wire and the side wall of the housing; the length of the humidity sensor substrate is greater than the width of all the temperature control wires and power supply wires arranged together.

2. The aircraft windshield terminal junction box according to claim 1, characterized in that: The humidity sensor is a resistive lithium oxide hygrometer, a dew point lithium chloride hygrometer, a carbon humidity-sensitive element, an alumina humidity-sensitive sensor, or a ceramic humidity sensor.

3. The aircraft windshield terminal junction box according to claim 1, characterized in that: The sensor base plate of the humidity sensor is located at the connection between the housing and the temperature control connector.

4. The aircraft windshield terminal junction box according to claim 1, characterized in that: The sensor substrate of the humidity sensor is located at the sealing silicone at the bottom of the windshield, and the other ends of the two humidity acquisition wires are inserted into the inner cavity of the housing from the wire lead-out end and connected to the temperature control connector.

5. The aircraft windshield terminal junction box according to claim 1, characterized in that: The humidity sensing wire is made of copper braided wire with a tin-plated layer, and an insulating sleeve made of insulating plastic is installed on the outside of the wire.

6. The aircraft windshield terminal junction box according to claim 1, characterized in that: A temperature sensor is installed inside the housing, and the temperature acquisition wire of the temperature sensor is connected to an unused terminal block.

7. A humidity detection method, based on the aircraft windshield terminal junction box as described in any one of claims 1-6, characterized in that: The method involves installing a humidity sensor inside the terminal junction box of the aircraft windshield, or installing a humidity sensor at the sealing silicone at the bottom of the aircraft windshield, and using the humidity sensor to collect humidity data. Then, it is determined whether the humidity exceeds a set threshold. If so, a prompt is made to replace the aircraft windshield.

Images