Flexible temperature sensing structure for wireless charging

Abstract

A flexible temperature sensing structure for wireless charging, said structure comprising: a flexible circuit board body (10); and a plurality of flexible temperature sensors (20), used for sensing temperature signals of corresponding areas of a transmitter and a receiver of a wireless charging device, wherein the plurality of flexible temperature sensors (20) are integrated within a region of the flexible circuit board body (10), a plurality of flexible transmission lines (1) are arranged on the flexible circuit board body (10), and each flexible temperature sensor (20) is externally connected to an analog-to-digital conversion circuit (30) and an MCU controller (40) by means of a corresponding flexible transmission line (1). The flexible temperature sensors (20) are used to detect temperature rise of a metal foreign object present in an alternating magnetic field, so as to identify the metal foreign object and promptly stop charging, thereby effectively ensuring charging safety.

Description

Flexible temperature sensing structure for wireless charging Technical Field

[0001] This invention relates to the technical field of wireless charging, specifically to a flexible temperature sensing structure applied to wireless charging. Background Technology

[0002] Wireless charging uses alternating magnetic fields to transfer energy. When a metallic foreign object is present in this alternating magnetic field, the object's temperature rises due to hysteresis loss and eddy current generation, posing a risk of burning or fire. Therefore, metallic foreign object detection is an essential protective function in wireless charging systems. Traditional metal foreign object detection solutions use a specific frequency signal to excite detection coils distributed throughout the transmitter to detect voltage and current changes caused by the metallic foreign object. This specific frequency is typically in the MHz range, different from the operating frequency of wireless charging power transmission. Consequently, existing solutions are costly and susceptible to electromagnetic interference during wireless charging power transmission, leading to false alarms or missed alarms. This results in poor charging safety and continuity, severely impacting the end-user experience and hindering the industrialization of wireless charging. Summary of the Invention

[0003] To address the aforementioned issues, this invention provides a flexible temperature sensing structure for wireless charging. This structure uses a flexible temperature sensor to detect the temperature rise of metallic foreign objects present in an alternating magnetic field, thereby identifying the metallic foreign objects and stopping charging in a timely manner, effectively ensuring charging safety.

[0004] A flexible temperature sensing structure for wireless charging, characterized in that it comprises:

[0005] Flexible circuit board body;

[0006] Several flexible temperature sensors are used to sense the temperature signals of corresponding areas at the transmitter and receiver of a wireless charging device.

[0007] The flexible circuit board body integrates several flexible temperature sensors within its surface area, and several flexible transmission lines are arranged on the flexible circuit board body. Each flexible temperature sensor is externally connected to an analog-to-digital converter circuit and an MCU controller through a corresponding flexible transmission line.

[0008] Its further features are:

[0009] The temperature-sensing material of the flexible temperature sensor is equivalent to a variable resistor in the sensing circuit. It outputs a resistance analog signal to the signal processing unit, and then processes the resistance value through the analog-to-digital conversion circuit and the MCU controller to calculate the temperature to be detected.

[0010] The flexible temperature sensor is arranged in a composite array based on the large and small temperature detection areas, which simplifies the signal harness of the flexible transmission line, resulting in lower cost of the temperature detection part and enabling mass production.

[0011] The flexible temperature sensor array is arranged on the first surface of the flexible circuit board body, the flexible transmission line is arranged on the second surface of the flexible circuit board body, the input end of the flexible transmission line is arranged according to the position of the flexible temperature sensor, and the output end of the flexible transmission line converges at the line output assembly.

[0012] It also includes a flexible connection transmission line arranged on the same surface as the flexible temperature sensor. The flexible connection transmission line is used to connect the flexible temperature sensors in the vicinity in series or in parallel to form a whole, so that the corresponding flexible transmission line only needs to connect several flexible temperature sensors connected through the flexible connection transmission line through a single contact point. The arrangement of the double-sided flexible line makes the setting of the flexible line simple and quick, and less prone to interference points.

[0013] Preferably, the line output assembly is provided with a plurality of output pins, and the corresponding output pins are connected to the analog-to-digital conversion circuit and the MCU controller through the connection port;

[0014] Preferably, the flexible connection transmission line is a flexible sensor array transmission line. Each flexible sensor array transmission line connects several flexible temperature sensors in parallel or series to form a flexible sensor area array. Each flexible temperature sensor arranged on the flexible circuit board body is assigned a corresponding position number. Each position number corresponds to a segmented area of ​​the flexible circuit board body. Each set of output pins corresponds to one flexible sensor array transmission line, covering the area to be detected. The resistance change of each flexible temperature sensor in the same set of flexible sensor area arrays will affect the signal output data of this array. The corresponding temperature value of the corresponding flexible sensor area array is obtained by the analog-to-digital conversion circuit and the MCU controller, thereby reliably obtaining the temperature of the corresponding area of ​​the wireless charging device. The position number corresponding to the flexible sensor array can be obtained by the MCU controller. Multiple sets of sensor arrays can be flexibly combined to cover detection areas of different sizes, adapting to the design of wireless charging coil modules of various sizes.

[0015] The flexible temperature sensor uses a carbon-based semiconductor metamaterial as the material for the sensing film.

[0016] The flexible temperature sensor is a resistive flexible sensor for temperature detection. The resistance of its sensing film changes with temperature. The material can be a conductive polymer, a carbon-based material, or a metal nanowire / particle.

[0017] Alternatively, the flexible temperature sensor may be a capacitive flexible sensor for temperature detection, utilizing the characteristic that the dielectric constant of the dielectric material changes with temperature, and reflecting the temperature through changes in capacitance; the dielectric constant of the flexible polymer dielectric layer changes with temperature, resulting in a change in capacitance value.

[0018] Alternatively, the flexible temperature sensor may be a thermoelectric flexible sensor for temperature detection, which is based on the Seebeck effect and consists of a circuit composed of two different conductors / semiconductors, with the temperature gradient generating a voltage difference.

[0019] This invention employs flexible temperature sensor technology. When the temperature-sensing material of the flexible temperature sensor senses a change in the physical quantity of temperature (taking temperature as an example here, similarly, capacitance or voltage difference could be used), the change in resistance in the sensing material will form a functional relationship with the temperature value. The temperature-sensing material of the flexible sensor is equivalent to a variable resistor in the sensing circuit. The signal processing unit outputs a resistance analog signal, which is processed by a general analog-to-digital converter and an MCU controller to calculate the temperature to be detected, thereby obtaining the temperature of the corresponding area of ​​the wireless charging device. Then, based on the temperature rise and temperature factors, it can determine whether there are metallic foreign objects in the corresponding area. The flexible temperature sensor has many excellent properties such as anti-electromagnetic interference, anti-vibration, high temperature resistance, and corrosion resistance, making it suitable for stable operation in high-demand environments such as automotive-grade environments. By using the flexible temperature sensor to detect the temperature rise of metallic foreign objects present in an alternating magnetic field, it can identify metallic foreign objects, stop charging in time, and effectively ensure charging safety. Attached Figure Description

[0020] Figure 1 is a schematic diagram of the arrangement of the flexible temperature sensor according to a specific embodiment of the present invention (the black line is on the front and the red line is on the back).

[0021] Figure 2 is a schematic diagram of the arrangement of the flexible temperature sensor according to a specific embodiment of the present invention (the black line is on the front and the red line is on the back).

[0022] Figure 3 is a circuit detection principle diagram of the present invention (taking carbon-based semiconductor metamaterials as an example);

[0023] The names corresponding to the serial numbers in the figure are as follows: Flexible circuit board body 10, Flexible temperature sensor 20, Analog-to-digital conversion circuit 30, MCU controller 40; Flexible transmission line 1, Line output terminal assembly 101, Flexible connection transmission line 2, Output PIN pin 3. Detailed Implementation

[0024] A flexible temperature sensing structure for wireless charging, as shown in Figures 1-3, includes: a flexible circuit board body 10 and several flexible temperature sensors 20.

[0025] The flexible temperature sensor 20 is used to sense the temperature signal of the corresponding area of ​​the transmitter and receiver of the wireless charging device;

[0026] The flexible circuit board body 10 integrates several flexible temperature sensors 20 within its surface area. The flexible circuit board body 10 has several flexible transmission lines 1 arranged on it. Each flexible temperature sensor 20 is externally connected to the analog-to-digital conversion circuit 30 and the MCU controller 40 through the corresponding flexible transmission line 1.

[0027] In practice: the temperature-sensing material of the flexible temperature sensor 20 is equivalent to a variable resistor in the sensing circuit (see Figure 3), outputs a resistance analog signal to the signal processing unit, and then the resistance value is processed by the analog-to-digital conversion circuit 30 and the MCU controller 40 to calculate the temperature to be detected.

[0028] The flexible temperature sensor 20 is arranged in a composite array based on the large temperature detection area, which simplifies the signal harness of the flexible transmission line 1, resulting in lower cost of the temperature detection part and enabling mass production.

[0029] In specific embodiments one and two, the flexible temperature sensor 20 array is arranged on the first surface of the flexible circuit board body 10, the flexible transmission line 1 is arranged on the second surface of the flexible circuit board body 10, the input end of the flexible transmission line 1 is arranged according to the position of the flexible temperature sensor 20, and the output end of the flexible transmission line 1 converges at the line output assembly 101.

[0030] In a specific embodiment, a flexible connection transmission line 2 is also included, which is arranged on the same surface as the flexible temperature sensor 20. The flexible connection transmission line 2 is used to connect the flexible temperature sensors 20 in the vicinity in series or in parallel to form a whole, so that the corresponding flexible transmission line 1 only needs to connect a number of flexible temperature sensors 20 connected through the flexible connection transmission line 2 through a single contact point. The arrangement of the double-sided flexible line makes the setting of the flexible line simple and quick, and less prone to interference points.

[0031] In specific embodiments one and two, the line output terminal assembly 101 is provided with a number of output pins 3, and the corresponding output pins 3 are connected to the analog-to-digital conversion circuit 30 and the MCU controller 40 through the connection port.

[0032] Each flexible temperature sensor 20 arranged on the flexible circuit board body 10 is assigned a corresponding number. Each number corresponds to a segmented area of ​​the flexible circuit board body. Each set of output pins 3 corresponds to a flexible transmission line 1. Each flexible transmission line 1 connects several flexible temperature sensors 20 in parallel or series. The corresponding temperature value of each segmented area of ​​the flexible circuit board body 10 is obtained by the analog-to-digital conversion circuit 30 and the MCU controller 40, thereby reliably obtaining the temperature of the corresponding area of ​​the wireless charging device.

[0033] In the first specific embodiment, there are 42 flexible temperature sensors. Each flexible temperature sensor is the same square shape and is numbered 1-42. Every 3 flexible temperature sensors are grouped into a flexible sensor area array, for a total of 14 groups of flexible sensor area arrays. Three adjacent groups of flexible temperature sensors in each row form a flexible sensor area array.

[0034] Forty-two flexible temperature sensors are arranged in a 7 (horizontal row) * 6 (vertical column) array according to the surface area of ​​the flexible circuit board body 10. The array of flexible sensor areas in each row is connected by flexible connection transmission lines 2 on the same surface. The entire line output assembly 101 is provided with 14 output pins, each output pin corresponding to a flexible transmission line. The flexible transmission lines are located on the back of the flexible circuit board body, which makes the connection clear and reliable.

[0035] In the second specific embodiment, there are 42 flexible temperature sensors. Each flexible temperature sensor is of the same circular shape and is numbered 1-42. Every 3 flexible temperature sensors are grouped into a flexible sensor region array, for a total of 14 groups of flexible sensor region arrays. Three adjacent groups of flexible temperature sensors in each row form a flexible sensor region array.

[0036] Forty-two flexible temperature sensors are arranged in a 7 (horizontal row) * 6 (vertical column) array according to the surface area of ​​the flexible circuit board body 10. The array of flexible sensor areas in each row is connected by a flexible connection transmission line 2 on the same surface. The entire line output assembly 101 is provided with 14 output pins, each output pin corresponding to a flexible transmission line. The flexible transmission line is located on the back of the flexible circuit board body, which makes the connection clear and reliable.

[0037] In a specific embodiment, the flexible temperature sensor uses a carbon-based semiconductor metamaterial as the material for the sensing film.

[0038] In addition, flexible temperature sensors can also be made of the following materials:

[0039] Flexible temperature sensors are based on resistive flexible sensors for temperature detection. The resistance of the sensing film material changes with temperature: when the material is a conductive polymer (such as PEDOT:PSS), the thermal motion of the molecular chains intensifies with increasing temperature, the carrier mobility decreases, and the resistance increases; when the material is a carbon-based material (graphene, carbon nanotubes), temperature changes cause enhanced lattice vibrations, increased electron scattering, and changes in resistance; when the material is a metal nanowire / particle (silver, copper), increasing temperature leads to enhanced lattice vibrations, and the resistivity increases linearly (similar to traditional metal resistance thermometers).

[0040] Alternatively, flexible temperature sensors can be based on capacitive flexible sensors for temperature detection, utilizing the property that the dielectric constant of a dielectric material changes with temperature, and reflecting temperature through changes in capacitance; the dielectric constant of a flexible polymer dielectric layer (such as PDMS) changes with temperature, resulting in a change in capacitance value;

[0041] Alternatively, flexible temperature sensors can be based on thermoelectric flexible sensors for temperature detection. They are based on the Seebeck effect, which consists of two different conductors / semiconductors forming a circuit, and the temperature gradient generates a voltage difference. Flexible thermoelectric materials (such as PEDOT:PSS and carbon nanotube composites) can realize flexible thermopile. Based on the sensitive material, supplemented by the substrate material, the sensing part of the flexible sensor can be fabricated.

[0042] The principle is as follows: When the temperature-sensing material of the flexible temperature sensor senses a change in the physical quantity of temperature (taking temperature as an example here, the same applies to capacitance or voltage difference), the change in resistance in the temperature-sensing material will form a functional relationship with the value of the physical quantity of temperature. The temperature-sensing material of the flexible sensor is equivalent to a variable resistor in the sensing circuit. The signal processing unit outputs a resistance analog signal, which is processed by a general analog-to-digital converter and MCU controller to calculate the temperature to be detected, thereby obtaining the temperature of the corresponding area of ​​the wireless charging device. Then, based on the temperature rise and temperature factors, it is determined whether there are metal foreign objects in the corresponding area. The flexible temperature sensor has many excellent properties such as anti-electromagnetic interference, anti-vibration, high temperature resistance and corrosion resistance, and is suitable for stable operation in high-requirement environments such as automotive-grade. It detects the temperature rise of metal foreign objects in an alternating magnetic field through the flexible temperature sensor, thereby identifying metal foreign objects and stopping charging in time, effectively ensuring charging safety.

[0043] It will be apparent to those skilled in the art that the present invention is not limited to the details of the exemplary embodiments described above, and that the invention can be implemented in other specific forms without departing from its spirit or essential characteristics. Therefore, the embodiments should be considered in all respects as exemplary and non-limiting, and the scope of the invention is defined by the appended claims rather than the foregoing description. Thus, all variations falling within the meaning and scope of equivalents of the claims are intended to be included within the present invention. No reference numerals in the claims should be construed as limiting the scope of the claims.

[0044] Furthermore, it should be understood that although this specification describes embodiments, not every embodiment contains only one independent technical solution. This narrative style is merely for clarity. Those skilled in the art should consider the specification as a whole, and the technical solutions in each embodiment can also be appropriately combined to form other embodiments that can be understood by those skilled in the art.

Claims

1. A flexible temperature sensing structure for wireless charging, characterized in that, It includes: Flexible circuit board body; Several flexible temperature sensors are used to sense the temperature signals of corresponding areas at the transmitter and receiver of a wireless charging device. The flexible circuit board body integrates several flexible temperature sensors within its surface area, and several flexible transmission lines are arranged on the flexible circuit board body. Each flexible temperature sensor is externally connected to an analog-to-digital converter circuit and an MCU controller through a corresponding flexible transmission line.

2. The flexible temperature sensing structure for wireless charging according to claim 1, characterized in that: The temperature-sensing material of the flexible temperature sensor is equivalent to a variable resistor in the sensing circuit. The signal processing unit outputs a resistance analog signal, which is then processed by an analog-to-digital converter and an MCU controller to calculate the temperature to be detected. 3.The flexible temperature sensing structure for wireless charging of claim 1, wherein: The flexible temperature sensor is arranged in a composite array based on the large and small temperature detection areas, which simplifies the signal harness of the flexible transmission line.

4. The flexible temperature sensing structure for wireless charging according to claim 1, characterized in that: The flexible temperature sensor array is arranged on the first surface of the flexible circuit board body, the flexible transmission line is arranged on the second surface of the flexible circuit board body, the input end of the flexible transmission line is arranged according to the position of the flexible temperature sensor, and the output end of the flexible transmission line converges at the line output assembly.

5. The flexible temperature sensing structure for wireless charging according to claim 4, characterized in that: It also includes a flexible connection transmission line arranged on the same surface as the flexible temperature sensor. The flexible connection transmission line is used to connect the flexible temperature sensors in the vicinity in series or in parallel to form a whole, so that the corresponding flexible transmission line only needs to connect several flexible temperature sensors connected through the flexible connection transmission line through a single contact.

6. The flexible temperature sensing structure for wireless charging according to claim 4 or 5, characterized in that: The line output assembly is provided with several output pins, and the corresponding output pins are connected to the analog-to-digital conversion circuit and the MCU controller through the connection port.

7. The flexible temperature sensing structure for wireless charging according to claim 6, characterized in that: The flexible connection transmission line is a flexible sensor array transmission line. Each flexible sensor array transmission line connects several flexible temperature sensors in parallel or series to form a flexible sensor area array. Each flexible temperature sensor arranged on the flexible circuit board body is assigned a corresponding position number. Each position number corresponds to a segmented area on the flexible circuit board body. Each set of output pins corresponds to one flexible sensor array transmission line, covering the area to be detected. The resistance change of each flexible temperature sensor in the same flexible sensor area array will affect the signal output data of this array. The corresponding temperature value of the corresponding flexible sensor area array is obtained by the analog-to-digital conversion circuit and the MCU controller, thereby reliably obtaining the temperature of the corresponding area of ​​the wireless charging device. The MCU controller also obtains the position number corresponding to the flexible sensor array. Multiple sensor arrays can be flexibly combined to cover detection areas of different sizes, adapting to the design of wireless charging coil modules of various sizes.

8. The flexible temperature sensing structure for wireless charging according to claim 1, characterized in that: The flexible temperature sensor uses a carbon-based semiconductor metamaterial as the material for the sensing film. 9.The flexible temperature sensing structure for wireless charging of claim 1, wherein: The flexible temperature sensor is a resistive flexible sensor for temperature detection, and the material resistance of its sensing film changes with temperature. Alternatively, the flexible temperature sensor may be a capacitive flexible sensor for temperature detection, utilizing the characteristic that the dielectric constant of the dielectric material changes with temperature, and reflecting the temperature through changes in capacitance; the dielectric constant of the flexible polymer dielectric layer changes with temperature, resulting in a change in capacitance value. Alternatively, the flexible temperature sensor may be a thermoelectric flexible sensor for temperature detection, which is based on the Seebeck effect and consists of a circuit composed of two different conductors / semiconductors, with the temperature gradient generating a voltage difference.

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