Digital communication thermocouple sensor for vehicle temperature monitoring

Abstract

The utility model relates to the technical field of temperature detection, and discloses a digital communication thermocouple sensor for vehicle temperature monitoring, which comprises a hot end, the hot end is at least connected with a group of wire harnesses, the other ends of the wire harnesses are connected with connectors, and the connectors are used for being connected with an upper computer or other control systems. An analog signal generated by the hot end is transmitted to the connector through the wire harness, and the internal structure of the connector processes the signal and converts the signal into a SENT data format based on time modulation coding, so that the whole sensor system can stably work in a complex electromagnetic environment in an automobile and effectively resist electromagnetic interference.

Description

Technical Field

[0001] This utility model relates to the field of temperature detection technology, and more specifically, to a digital communication thermocouple sensor for vehicle temperature monitoring. Background Technology

[0002] Thermocouples are based on the Seebeck effect, which states that when two different metals are connected to form a closed circuit and the two junctions are at different temperatures, an electromotive force is generated in the circuit. This characteristic allows thermocouples to be used to measure temperature differences and convert them into electrical signals for processing.

[0003] Traditional thermocouple sensors typically use analog outputs to represent temperature information through changes in voltage or current; however, this method is susceptible to electromagnetic interference (EMI) and its accuracy decreases over long distances.

[0004] While CAN (Controller Area Network) offers good reliability and real-time performance and is suitable for communication with various types of sensors, its high cost and relatively slow data transmission rate make it less than optimal for exhaust system temperature monitoring.

[0005] While RS485 and RS232 are two serial communication standards that can meet data transmission requirements within a certain range, they face problems such as complex wiring and insufficient anti-interference performance in the automotive environment, especially when facing high-speed, low-latency application scenarios.

[0006] Therefore, there is an urgent need for a digital communication thermocouple sensor for vehicle temperature monitoring that offers fast transmission speed, easy installation, and low cost to solve the above problems. Utility Model Content

[0007] The purpose of this invention is to provide a digital communication thermocouple sensor for vehicle temperature monitoring, in order to solve the problems existing in the prior art.

[0008] To achieve the above objectives, this utility model provides the following solution: This utility model provides a digital communication thermocouple sensor for vehicle temperature monitoring, with a hot end, at least one set of wire harnesses connected to the hot end, and the other end of the wire harnesses connected to a connector, which is used to connect to a host computer or other control system.

[0009] According to the present invention, a digital communication thermocouple sensor for vehicle temperature monitoring is provided. The wiring harness includes a connecting terminal, a first compensating wire, and a second compensating wire. The connecting terminal is used to connect the hot end and the first and second compensating wires. The first compensating wire is connected to the negative terminal of the hot end, and the second compensating wire is connected to the positive terminal of the hot end. The other ends of the first and second compensating wires are connected to the connector.

[0010] According to the present invention, a digital communication thermocouple sensor for vehicle temperature monitoring is provided. The connector includes a carrier, and a motherboard is installed inside the carrier. The motherboard is used to process and encode the signals collected by the sensor and to communicate with external systems.

[0011] According to the present invention, a digital communication thermocouple sensor for vehicle temperature monitoring is provided, wherein a positioning ring and a screw are provided on the hot end, the positioning ring is fixedly connected to the hot end, and the screw is screwed into a reserved threaded hole to fix the hot end and prevent the hot end from loosening or displacing.

[0012] According to the present invention, a digital communication thermocouple sensor for vehicle temperature monitoring is provided, wherein a fluoropolymer plug is also installed on the wiring harness, the fluoropolymer plug covering the connection terminal to protect the connection terminal and provide waterproofing.

[0013] According to the present invention, a digital communication thermocouple sensor for vehicle temperature monitoring is provided, wherein the wiring harness is further provided with a connector end cover, which is used to fix the connector and the fluoropolymer plug.

[0014] According to the present invention, a digital communication thermocouple sensor for vehicle temperature monitoring is provided, wherein a fiberglass sleeve is provided on the wiring harness, and the fiberglass sleeve is provided outside the first compensation wire and the second compensation wire to protect the first compensation wire and the second compensation wire.

[0015] According to the present invention, a digital communication thermocouple sensor for vehicle temperature monitoring is provided, wherein a tail tube is provided on the hot end, the tail tube is used to fix the hot end and the fluororubber plug, the tail tube is welded to the hot end and the tail tube is fixed to the fluororubber plug by a tube buckle.

[0016] The present invention discloses the following technical effects:

[0017] In this application, the analog signal generated by the hot end is transmitted to the connector via a wiring harness. The connector's internal structure processes the signal, converting it into a SENT data format based on time modulation coding. This enables the entire sensor system to operate stably in the complex electromagnetic environment inside the vehicle and effectively resist electromagnetic interference. SENT communication requires only a single wire, which greatly reduces the number of connections between the sensor and the controller. Attached Figure Description

[0018] To more clearly illustrate the technical solutions in the embodiments of this utility model or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of this utility model. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0019] Figure 1 This is a schematic diagram of the overall structure of this utility model;

[0020] Figure 2 This is a schematic diagram illustrating the working principle of the thermoelectric effect (also known as the Seebeck effect).

[0021] Among them, 1. hot end; 2. positioning ring; 3. screw; 4. connecting terminal; 5. first compensating wire; 6. second compensating wire; 7. fluororubber plug; 8. tail tube; 9. fiberglass sleeve; 10. main board; 11. carrier; 12. connector; 13. connector tail cover. Detailed Implementation

[0022] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model.

[0023] To make the above-mentioned objectives, features and advantages of this utility model more apparent and understandable, the utility model will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0024] like Figure 1 As shown, this utility model provides a digital communication thermocouple sensor for vehicle temperature monitoring, comprising: a hot end 1, at least one set of wire harnesses connected to the hot end 1, and a connector 12 connected to the other end of the wire harnesses, the connector 12 being used to connect to a host computer or other control system.

[0025] Hot end 1 is placed in the environment to be tested (such as inside the exhaust pipe or near the exhaust flow), directly contacting the high-temperature exhaust gas, forming a temperature difference with the "cold end" which is at a lower ambient temperature, and generating thermoelectric potential based on the Seebeck effect.

[0026] The wiring harness includes a connecting terminal 4, a first compensating wire 5, and a second compensating wire 6. The connecting terminal 4 connects the hot end 1 to the first compensating wire 5 and the second compensating wire 6, ensuring stable transmission of electrical signals. After the hot end 1 is heated, its positive and negative terminals can be distinguished using a multimeter in mV mode. The first compensating wire 5 is connected to the negative terminal of the hot end 1, and the second compensating wire 6 is connected to the positive terminal of the hot end 1. The other ends of the first compensating wire 5 and the second compensating wire 6 are connected to the connector 12. The first compensating wire 5 and the second compensating wire 6 transmit the electrical signals generated by the hot end 1 to the connector 12.

[0027] The connector 12 contains a carrier 11, which contains a motherboard 10. The connector 12 connects the sensor to a host computer or other control system. The carrier 11 inside is used to install the motherboard 10, which is used to process and encode the signals collected by the sensor and communicate with external systems.

[0028] The hot end 1 is provided with a positioning ring 2 and a screw 3. The positioning ring 2 is laser welded at a designated position on the hot end 1, and the screw 3 is screwed into a reserved threaded hole to fix the hot end 1 and prevent the hot end 1 from loosening or shifting.

[0029] Fluoropolymer plugs 7 are installed on the wiring harness, covering the connection terminals 4 to protect and waterproof them, preventing the internal connection terminals 4 from being affected by the external environment and ensuring the reliability of signal transmission. A connector end cover 13 is also installed on the wiring harness, which secures the connector 12 and the fluoropolymer plugs 7 with tubular clips, further enhancing the overall structural stability of the sensor.

[0030] The wiring harness also includes a fiberglass sleeve 9, which is sleeved on the first compensating conductor 5 and the second compensating conductor 6 to protect the first compensating conductor 5 and the second compensating conductor 6 from interference by external factors and to ensure the stability of signal transmission.

[0031] A tail tube 8 is also provided on the hot end 1. The tail tube 8 fixes the hot end 1 and the fluororubber plug 7. The tail tube 8 is fixed to the hot end 1 by side welding and to the fluororubber plug 7 by side tube buckle to enhance the stability of the connection between the hot end 1 and the fluororubber plug 7.

[0032] During installation, place the hot end 1 into the environment to be tested, such as inside an exhaust pipe or near the exhaust flow, ensuring that the hot end 1 can fully contact the high-temperature exhaust gas for accurate temperature measurement. Tighten screw 3 until it is screwed into the pre-drilled threaded hole to secure the hot end 1. Connect connector 12 to a host computer or other control system to enable data transmission between the sensor and external devices.

[0033] During signal processing, after the hot end 1 is heated, its positive and negative terminals can be distinguished using a multimeter in mV mode. Internal connection terminal 4 connects the hot end 1 to the first compensation wire 5 and the second compensation wire 6. The first compensation wire 5 is connected to the negative terminal of the hot end 1, and the second compensation wire 6 is connected to the positive terminal of the hot end 1, ensuring accurate transmission of the electrical signal to connector 12. A motherboard 10 is installed on the carrier 11 inside connector 12. The motherboard 10 performs subsequent processing on the transmitted signal, including analog signal acquisition, signal conditioning, digitization, data processing, SENT encoding, and transmission.

[0034] like Figure 2 As shown, based on the Seebeck effect, when two conductors A and B of different compositions are combined into a closed loop, and the two nodes T and T0 of the closed loop are placed in environments with different temperatures, a thermoelectric potential will be generated in the loop. This phenomenon is called the "thermoelectric effect." Thermocouple sensors typically consist of two different conductors or semiconductor materials, such as nickel-chromium alloy and constantan, which are welded together to form a junction. This junction, called the "hot end," is placed inside the exhaust pipe or near the exhaust flow to directly contact the high-temperature exhaust gas. When the "hot end" is exposed to the high-temperature environment of the exhaust system, a significant temperature difference is formed between it and another junction—the "cold end"—which remains at a lower ambient temperature. According to the Seebeck effect, this temperature difference will generate a small DC voltage (in the mV range) between the thermocouple materials. The magnitude of this voltage is proportional to the temperature difference and can be converted into a temperature reading using a calibrated formula.

[0035] In practical applications, the following is a detailed process from thermocouple to SENT output:

[0036] 1. Analog signal acquisition

[0037] Thermocouple measurement: A thermocouple generates a tiny DC voltage (in the mV range) that is proportional to the temperature difference between the two junctions.

[0038] 2. Signal conditioning

[0039] Linearization: The relationship between the output voltage and temperature of a thermocouple is non-linear, so the signal needs to be linearized for subsequent processing and interpretation.

[0040] 3. Digitalization

[0041] Analog-to-digital conversion (ADC): The conditioned analog signal is fed into an analog-to-digital converter (ADC) to convert it into digital format; the ADC can be integrated into a dedicated integrated circuit (IC) or as part of a microcontroller.

[0042] Cold junction compensation: The ADC will also read the data from the cold junction temperature sensor and combine it with the output of the thermocouple to calculate the final temperature value using mathematical algorithms.

[0043] 4. Data Processing

[0044] Microcontroller processing: The digitized data is further processed by the microcontroller, which may include operations such as calibration and diagnostic checks. These processing steps ensure the accuracy of the data and add necessary metadata, such as checksums and status information.

[0045] 5. SENT encoding

[0046] Time modulation: The processed temperature data is encoded according to the requirements of the SENT protocol. Each data packet consists of a series of nibbles, each nibble occupying a fixed time interval (e.g., 600 microseconds), while the actual valid data is encoded according to the different pulse end positions.

[0047] Frame structure construction: In addition to temperature data, a complete SENT frame structure must be constructed, including the start frame, data frame, checksum, etc., to ensure that the receiver can correctly parse the received information.

[0048] 6. SENT transmission

[0049] Single-wire communication: Finally, the encoded data is sent to the electronic control unit (ECU) via a single signal line. In this process, only one wire is needed to complete the data transmission from the sensor to the ECU, greatly simplifying the wiring complexity.

[0050] The working principle of this application is as follows: The hot junction 1 is placed in the environment to be measured, and the screw 3 is screwed into the reserved threaded hole to fix it in place. After connecting with the connector 12, it can communicate with this utility model to measure the temperature. Specifically, a temperature difference is formed between the hot junction 1 and the "cold junction," generating a small DC voltage (mV level) based on the Seebeck effect. This voltage is proportional to the temperature difference. Analog signal acquisition is then performed. The voltage generated by the thermocouple is linearized and conditioned, and then converted into digital format by an analog-to-digital converter (ADC). Simultaneously, the ADC reads the cold junction temperature sensor data, performs cold junction compensation processing, and calculates the final temperature value. The digitized data is processed by the microcontroller, including calibration, diagnostic checks, and other operations. The processed temperature data is encoded according to the SENT protocol to construct a complete SENT frame structure containing a start frame, data frame, checksum, etc. Finally, the encoded data is sent to the electronic control unit (ECU) through a single signal line.

[0051] Compared with the prior art, this application:

[0052] With strong resistance to electromagnetic interference, SENT communication, based on time-modulated encoded data, exhibits superior resistance to power fluctuations and electromagnetic noise. Structurally, the analog signal generated by hot-end 1 is transmitted via internal connection terminal 4 to the first compensation wire 5 and the second compensation wire 6, and then to the main board 10 within connector 12. The main board 10 is responsible for signal processing, including encoding according to the SENT protocol. The coordination between hot-end 1, the wiring harness, and the main board 10 is crucial in this process. Hot-end 1 stably generates the signal, the wiring harness ensures signal transmission, and the main board 10 converts the signal into SENT data format based on time-modulated encoding, enabling the entire sensor system to operate stably in the complex electromagnetic environment inside the vehicle and effectively resist electromagnetic interference.

[0053] Simplified wiring allows SENT communication to be completed with only a single wire, significantly reducing the number of connections between sensors and controllers. In this invention, the first compensating wire 5 and the second compensating wire 6 of the wiring harness transmit the signal from the hot end 1 to the connector 12, which connects to the external control system. Compared to traditional multi-wire communication, SENT communication relies on only one wire in this set (logically single-wire communication) to complete data transmission, eliminating the need for complex multi-wire layouts. The design of connector 12 and motherboard 10 is also closely optimized for SENT communication, further reducing wiring complexity and overall vehicle wiring costs.

[0054] High-speed data transmission: The sensor supports data transmission rates up to 20Mbps, enabling rapid response and high-precision temperature measurement. Hot junction 1 acquires temperature data, generating an analog signal. This signal is transmitted via internal connection terminal 4 to a compensation wire, and then via connector 12 to the mainboard 10. The mainboard 10 integrates signal conditioning, analog-to-digital conversion, data processing, and SENT encoding modules. These modules work together to rapidly process the analog signal, converting it into a digital signal and encoding it according to the SENT protocol. The encoded data is then rapidly transmitted to the electronic control unit (ECU) via a single wire. The efficient coordination of hot junction 1, the wiring harness, and the mainboard 10 ensures rapid data transmission throughout the entire process, meeting the demands of high-speed data transmission.

[0055] The diagnostic function includes diagnostic information in each data frame for easy maintenance. During data processing, the motherboard 10 processes the digitized data and adds diagnostic information such as checksums and sensor health status. Temperature data collected by hot-end 1 is transmitted to the motherboard 10 via the wiring harness. The motherboard 10 constructs a complete SENT frame structure from the processed data, which includes diagnostic information. This information is transmitted to the ECU along with the data frame via connector 12 and a single wire. The cooperation of hot-end 1, the wiring harness, the motherboard 10, and the SENT frame structure enables the sensor's diagnostic function, allowing maintenance personnel to promptly understand the sensor's operating status and quickly locate and resolve problems.

[0056] In the description of this utility model, it should be understood that the terms "longitudinal", "lateral", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", etc., indicate the orientation or positional relationship based on the orientation or positional relationship shown in the accompanying drawings. They are only for the convenience of describing this utility model 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 utility model.

[0057] The embodiments described above are merely preferred embodiments of the present utility model and are not intended to limit the scope of the present utility model. Various modifications and improvements made to the technical solutions of the present utility model by those skilled in the art without departing from the spirit of the present utility model should fall within the protection scope defined by the claims of the present utility model.

Claims

1. A digital communication thermocouple sensor for vehicle temperature monitoring, characterized in that, include: A hot end (1) is connected to at least one set of wire harnesses, and the other end of the wire harnesses is connected to a connector (12), which is used to connect to a host computer or other control system. The wiring harness includes a connecting terminal (4), a first compensating wire (5), and a second compensating wire (6). The connecting terminal (4) is used to connect the hot end (1) and the first compensating wire (5) and the second compensating wire (6). The first compensating wire (5) is connected to the negative terminal of the hot end (1), and the second compensating wire (6) is connected to the positive terminal of the hot end (1). The other ends of the first compensating wire (5) and the second compensating wire (6) are connected to the connector (12). The connector (12) includes a carrier (11), in which a motherboard (10) is installed. The motherboard (10) is used to process and encode the signals collected by the sensor and to communicate with external systems. The hot end (1) is provided with a positioning ring (2) and a screw (3). The positioning ring (2) is fixedly connected to the hot end (1), and the screw (3) is screwed into the reserved threaded hole to fix the hot end (1) and prevent the hot end (1) from loosening and shifting. The wiring harness is also equipped with a fluoropolymer plug (7), which covers the connecting terminal (4) to protect the connecting terminal (4) and provide waterproofing. The wiring harness is also provided with a connector tail cover (13), which is used to fix the connector (12) and the fluoropolymer plug (7). A fiberglass sleeve (9) is provided on the wire harness. The fiberglass sleeve (9) is provided outside the first compensating wire (5) and the second compensating wire (6) to protect the first compensating wire (5) and the second compensating wire (6). A tail tube (8) is provided on the hot end (1). The tail tube (8) is used to fix the hot end (1) and the fluororubber stopper (7). The tail tube (8) is welded to the hot end (1) and the tail tube (8) is fixed to the fluororubber stopper (7) by a tube buckle.

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