Device and method for testing temperature of piston in real time

Abstract

The invention discloses a device for testing the temperature of a piston in real time, and the device comprises at least one temperature sensor which is disposed at a temperature measurement point of the surface of the piston, the temperature measurement part of the temperature sensor is exposed out of the surface of the piston, and a K-type thermocouple is disposed in the temperature sensor; the temperature measurement module is mounted at the bottom of a pin seat of the piston and comprises a heat insulation plate, a chip, a high-temperature-resistant battery and a temperature control switch, and the heat insulation plate is in contact with the bottom of the pin seat; the chip is used for receiving the temperature data transmitted by the temperature sensor and converting the temperature data into a wireless temperature signal; the high-temperature-resistant battery supplies power to the chip; the temperature control switch is arranged between the high-temperature-resistant battery and the chip and used for sensing the temperature transmitted by the piston. The temperature sensor penetrates through an internal channel of the piston through a wire and is connected with the chip; the signal receiver is arranged outside the internal combustion engine and used for receiving the wireless temperature signal sent by the temperature measuring module; and the upper computer is connected with the signal receiver and is used for converting the wireless temperature signal into a temperature numerical value and displaying and recording the temperature numerical value.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of engine and test related technology, in particular to a device and method for testing piston temperature in real time. BACKGROUND

[0002] In the power transmission system of an internal combustion engine, the piston is a core key part directly bearing the extreme working conditions of the combustion chamber, and its working state directly determines the operating efficiency and reliability of the internal combustion engine. The explosion process of fuel in the combustion chamber releases a large amount of heat energy, and the instantaneous temperature of the combustion chamber can reach above 1000℃, and after heat conduction, the surface temperature of the piston still maintains in a high temperature interval of 300℃ to 500℃; at the same time, the burst pressure generated in the explosion moment can reach 100~300bar, and combined with the high-speed reciprocating motion of the piston per minute, the piston is long-term in a compound harsh environment of "high temperature, high pressure, and high frequency alternating load". Such extreme working conditions put strict requirements on the material heat resistance and structure deformation resistance of the piston, and under different combustion boundaries (such as different rotating speeds, loads, and ignition times), the temperature distribution of different parts of the piston top, ring groove, and pin seat is significantly different. These temperature data are the core basis for evaluating the thermal fatigue life of the piston, optimizing the structural design, and verifying the material selection, and therefore, accurately obtaining the temperature information of each part of the piston is an indispensable key test link in the development process of the internal combustion engine.

[0003] The current mainstream piston temperature test method in the industry is the hardness plug method, which requires first machining a threaded hole in the piston part to be tested, then rotating a hardness plug made of special heat-resistant alloy into the hole to ensure that the hardness plug is flush with the surface of the piston and in close contact; after completing the installation, the internal combustion engine is placed on the test bench to run under the preset working conditions, and after the test is completed and the engine is stopped, the piston is disassembled and removed, the surface hardness of the hardness plug is measured by a special hardness detection device, and then the temperature value of the test point during the test is calculated according to the pre-labeled "hardness-temperature corresponding curve" of the material. However, this method has obvious limitations: on the one hand, the hardness plug can only record the highest temperature of the test point during the test period, and cannot capture the dynamic temperature change of the piston during the switching process of different working conditions, making it difficult to restore the complete time sequence characteristics of the temperature field; on the other hand, due to the influence of the batch consistency of the hardness plug material, the machining precision of the threaded hole, and the installation fit, the error of the test results is usually above ±15℃, and the hardness plug needs to be replaced after each test, which not only is complicated to operate and has a long test period, but also greatly increases the test cost and time cost during the development stage of the internal combustion engine.

[0004] The disclosure of the above background art content is only used to assist in understanding the concept and technical solutions of the present application, and it does not necessarily belong to the prior art of the present patent application. In the absence of explicit evidence that the above content has been disclosed on the filing date of the present patent application, the above background art should not be used to evaluate the novelty and inventiveness of the present application. Summary of the Invention

[0005] The purpose of this invention is to propose a device and method for real-time testing of piston temperature, in order to solve the technical problems of the prior art, such as the hardness tester method only being able to obtain the highest temperature of the piston measuring point, being unable to capture the dynamic temperature changes under different operating conditions, having large testing errors, being cumbersome and time-consuming to operate, and being unable to meet the needs of internal combustion engine research and development for accurate analysis of the piston temperature field.

[0006] Therefore, the present invention proposes a device for real-time testing of piston temperature.

[0007] Preferably, the present invention may also have the following technical features:

[0008] A device for real-time testing of piston temperature, comprising:

[0009] At least one temperature sensor is installed at a temperature measuring point on the piston surface. The temperature measuring part of the temperature sensor is exposed on the piston surface and has a built-in K-type thermocouple.

[0010] A temperature sensing module is installed at the bottom of the piston pin seat. The module includes a heat insulation plate, a chip, a high-temperature resistant battery, and a temperature control switch. The heat insulation plate contacts the bottom of the pin seat to isolate heat transferred from the piston. The chip receives temperature data from the temperature sensor and converts it into a wireless temperature signal. The high-temperature resistant battery powers the chip. The temperature control switch is located between the high-temperature resistant battery and the chip to sense the temperature transferred from the piston and control the circuit connection between the battery and the chip. The temperature sensor is connected to the chip via a wire passing through the internal channel of the piston to transmit temperature data.

[0011] A signal receiver, located outside the internal combustion engine, is used to receive the wireless temperature signal sent by the temperature measurement module;

[0012] The host computer is connected to the signal receiver and is used to convert the wireless temperature signal into temperature values ​​and display and record them.

[0013] Preferably, the temperature measuring module is detachably fixed to the bottom of the piston pin seat by screws, and the exposed circuit, solder joints, and wire-to-chip connectors of the temperature measuring module are all filled with high-temperature resistant sealant, the temperature resistance of which is not less than 300°C.

[0014] Preferably, the chip is a multi-channel data acquisition chip that can simultaneously receive measurement data from 8-16 channels of the temperature sensors, and the frequency of the wireless temperature signal output by the chip can be adjusted by a preset program, with an adjustment range of 1Hz-10Hz.

[0015] Preferably, the temperature control switch is a bimetallic strip temperature control switch with a temperature trigger threshold of 60°C. When the sensed piston temperature reaches 60°C, the circuit is turned on, and when the temperature is below 50°C, the circuit is turned off.

[0016] Preferably, the temperature control switch achieves heat conduction with the bottom of the pin seat through a metal heat-conducting sheet. One end of the metal heat-conducting sheet is tightly fitted with the outer shell of the temperature control switch, and the other end passes through the heat insulation plate and contacts the bottom of the pin seat.

[0017] Preferably, the temperature measuring point structure on the piston surface is adapted to the temperature sensor, the temperature measuring point is a stepped hole, and the temperature sensor is fixed to the hole wall by high-temperature resistant adhesive.

[0018] Preferably, the temperature measuring point structure on the piston surface is adapted to the temperature sensor, the temperature measuring point is an internal threaded hole, and the tail of the temperature sensor is provided with an external thread, which is fixed by thread engagement.

[0019] Preferably, the head of the temperature sensor is a temperature measuring end, and the material of the head is the same as that of the piston, and the end face of the head is flush with the surface of the piston to ensure accurate temperature measurement.

[0020] Preferably, the internal channel of the piston is a lubricating oil channel built into the piston or a specially machined wire channel; the inner wall of the wire channel is provided with a high-temperature resistant insulating layer, and after the wire is inserted into the channel, the gap between the channel and the wire is filled with high-temperature insulating glue.

[0021] A method for real-time testing of piston temperature, employing the aforementioned apparatus for real-time testing of piston temperature, the testing method comprising the following steps:

[0022] (a) Install at least one temperature sensor at a temperature measuring point on the surface of the piston, fix the temperature measuring module to the bottom of the piston pin seat, and electrically connect the temperature sensor and the chip of the temperature measuring module through a wire through the internal channel of the piston.

[0023] (b) Assemble the complete engine in accordance with the technical requirements for internal combustion engine installation, and transfer the complete engine to the test bench or vehicle;

[0024] (c) Place the signal receiver outside the internal combustion engine and connect the signal receiver to the host computer to establish a wireless temperature signal transmission link;

[0025] (d) Start the internal combustion engine. When the temperature control switch in the temperature measurement module senses that the temperature transmitted by the piston reaches 60°C, the temperature control switch conducts the circuit between the high-temperature resistant battery and the chip, and the temperature measurement module starts and begins to collect the temperature data transmitted by the temperature sensor.

[0026] (e) Set the operating conditions of the internal combustion engine according to the test requirements, and collect and record piston temperature data and internal combustion engine operating signals synchronously through the host computer;

[0027] (f) After the test is completed, the internal combustion engine is stopped. When the temperature transmitted by the piston sensed by the temperature control switch is lower than the 50°C reset threshold, the temperature control switch disconnects the circuit and the system returns to the shutdown state.

[0028] The beneficial effects of this invention compared to the prior art include:

[0029] 1. The device of the present invention integrates the temperature measuring module into the bottom of the piston pin seat and is equipped with a combination design of heat insulation plate, high temperature resistant battery and temperature control switch. This design effectively isolates the high temperature transmitted by the piston and can adapt to the extreme working scenario of "high temperature, high speed and high oil mist" of the piston, thus ensuring the long-term stable operation of the device during the testing process.

[0030] 2. The temperature sensor of the present invention adopts a design of "exposed temperature measuring part + head of the same material as piston" and is matched with a stepped hole or threaded hole mounting structure, which not only ensures the accuracy of temperature measurement (error ≤ ±1℃) but also can withstand the high explosion pressure in the combustion chamber, preventing the sensor from falling off during the test and significantly improving the reliability of the test device.

[0031] 3. The temperature control switch of the present invention adopts a bimetallic strip structure and a heat conduction design with a metal heat-conducting sheet. It can automatically switch the circuit on and off according to the piston temperature and cut off the power supply when the piston has not reached the working temperature, effectively saving the power of the high-temperature resistant battery and increasing the device's battery life to more than 200 hours, which is suitable for long-term testing requirements of bench testing or vehicle road testing.

[0032] 4. The real-time piston temperature testing method of the present invention realizes the synchronous acquisition of piston temperature data and internal combustion engine operating signals (speed, torque, throttle, etc.), and can directly analyze the influence of different operating conditions on piston temperature, providing direct technical basis for adjusting the combustion boundary of internal combustion engine and optimizing piston materials and structure, thus helping to improve the operating efficiency and reliability of internal combustion engine. Attached Figure Description

[0033] Figure 1 This is a first structural schematic diagram of a specific embodiment of the present invention.

[0034] Figure 2 This is a second structural schematic diagram of a specific embodiment of the present invention.

[0035] Figure 3 This is a schematic diagram of a temperature sensor according to a specific embodiment of the present invention.

[0036] Figure 4 This is a third structural schematic diagram of a specific embodiment of the present invention.

[0037] Explanation of reference numerals in the attached diagram: 1-Piston; 11-Stepped hole; 2-Temperature measuring module; 21-Chip; 22-Chip; 23-High temperature resistant battery; 24-Temperature control switch; 3-Signal receiver; 4-Host computer; 5-Temperature sensor. Detailed Implementation

[0038] The present invention will now be described in further detail with reference to specific embodiments and the accompanying drawings. It should be emphasized that the following description is merely exemplary and is not intended to limit the scope or application of the present invention.

[0039] Non-limiting and non-exclusive embodiments will be described with reference to the following figures, wherein the same reference numerals denote the same parts unless otherwise specifically stated.

[0040] Example 1:

[0041] This embodiment provides a device for real-time testing of piston temperature, mainly used in bench testing or vehicle testing during the internal combustion engine development phase. Figures 1-4 As shown, where Figure 2To illustrate this clearly, the temperature measurement module is enlarged proportionally. The device specifically includes: at least one temperature sensor 5, a temperature measurement module 2, a signal receiver 3, and a host computer 4. The temperature sensor 5 is installed at temperature measurement points on the surface of the piston 1, specifically on the top, side (circumferential land), and bottom surfaces of the piston. The temperature measurement part of the temperature sensor 5 is exposed on the surface of the piston 1 and has a built-in K-type thermocouple. The K-type thermocouple has a temperature measurement range of -200℃ to 1300℃, suitable for the piston 1's operating temperature of 300℃ to 500℃. The temperature measurement module 2 is installed at the bottom of the piston 1's pin seat and includes a heat insulation plate 21, a chip 22, a high-temperature resistant battery 23, and a temperature control switch 24. The heat insulation plate 21 contacts the bottom of the pin seat to isolate the voltage transmitted by the piston 1. The heat insulation plate 21 is made of ceramic fiber material with a temperature resistance of ≥500℃, which can isolate more than 80% of the heat transferred by the pin seat, keeping the chip 22 and battery in an operating environment below 80℃. The chip 22 is used to receive the temperature data transmitted by the temperature sensor 5 and convert it into a wireless temperature signal. The chip 22 uses a multi-channel MCU and has a built-in Bluetooth communication module. The high-temperature resistant battery 23 powers the chip 22. The temperature control switch 24 is located between the high-temperature resistant battery 23 and the chip 22 to sense the temperature transmitted by the piston 1 and control the high-temperature resistant battery. The circuit between pool 23 and chip 22 is switched on and off; the temperature sensor 5 is connected to the chip 22 via a wire passing through the internal channel of piston 1 to transmit temperature data. Specifically, an unused branch of the lubrication oil passage of piston 1 can be used, which does not affect the lubrication and cooling function of piston 1, or a specially processed wire channel can be used. The inner wall of the channel is provided with a high-temperature resistant insulating layer, such as a polyimide insulating varnish with a temperature resistance of ≥200℃. After the wire is inserted into the channel, the gap between the channel and the wire is filled with high-temperature insulating glue, such as epoxy resin glue with a temperature resistance of ≥180℃. The original lubrication oil passage of piston 1 can be utilized or an additional layer can be added. The dedicated wire hole ensures sufficient space for wire laying without affecting the original function of piston 1. The insulation layer and high-temperature insulating adhesive prevent short circuits between the wire and the metal body of piston 1, improving signal transmission stability. The signal receiver 3 is positioned externally to the internal combustion engine, such as on a test bench, at a distance of ≤5 meters from the piston, ensuring it can receive the wireless temperature signal sent by the temperature measurement module 2. The host computer 4 connects to the signal receiver 3 via a USB interface. The host computer 4 carries testing software that converts the wireless temperature signal into temperature values, displays the temperature curve in real time, and records the data. This device overcomes the limitations of the traditional hardness test's "static posterior" method, achieving real-time temperature acquisition during piston 1 movement and simultaneously recording dynamic temperature changes, providing accurate data for piston 1 temperature field research.

[0042] In some examples of this embodiment, the temperature sensing module 2 is detachably fixed to the bottom of the piston 1 pin seat by screws. Specifically, two M2 hexagon socket screws can be used. Two threaded fixing holes are pre-machined at the bottom of the pin seat. The exposed circuitry, solder joints, and connectors of the wires and chips 22 of the temperature sensing module 2 are all filled with high-temperature resistant sealant, such as 704 silicone rubber with a temperature resistance rating of not less than 300℃. The detachable screw fixing method facilitates the reuse of the device and reduces testing costs; the high-temperature resistant sealant can effectively isolate oil mist and moisture at the bottom of the piston 1, preventing circuit corrosion and improving the reliability of the device in harsh environments.

[0043] In other examples of this embodiment, chip 22 is a multi-channel data acquisition chip 22, which can simultaneously receive measurement data from 8-16 temperature sensors 5. The 8 channels correspond to core measurement points such as the top of piston 1, the vicinity of the first annular groove, the vicinity of the second annular groove, and the pin seat, while the 16 channels can cover more areas of piston 1 (achieving full temperature field measurement). Furthermore, the frequency of the wireless temperature signal output by chip 22 can be adjusted via a preset program, ranging from 1Hz to 10Hz. 1Hz is suitable for steady-state testing, while 10Hz is suitable for transient testing such as rapid acceleration and deceleration. The program is written to chip 22 via a serial port programming tool. The multi-channel design allows for simultaneous acquisition of temperatures from different parts of piston 1, completely restoring the temperature field distribution; the adjustable signal transmission frequency adapts to different test scenarios, balancing data accuracy and transmission efficiency.

[0044] In some examples of this embodiment, the temperature control switch 24 is a bimetallic strip temperature control switch 24, with a temperature trigger threshold set to 60°C. When the temperature transmitted by the piston 1 reaches 60°C, the circuit is turned on; when the temperature is below 50°C, the circuit is turned off. The bimetallic strip is made of copper-nickel alloy, and the thermal response time is ≤5s. Specifically, the temperature control switch 24 achieves heat conduction through a metal heat-conducting sheet and the bottom of the pin seat. The metal heat-conducting sheet is a 0.5mm thick copper sheet, one end of which is tightly fitted to the outer shell of the temperature control switch 24, and the other end passes through a special opening in the heat insulation plate 21 and contacts the bottom of the pin seat. The opening is filled with heat-insulating sealant to ensure heat conduction without damaging the heat insulation effect of the heat insulation plate 21. The bimetallic strip temperature control switch 24 does not require an additional power supply; it automatically turns the circuit on and off based solely on the temperature of the piston 1, effectively saving battery power. The metal heat-conducting sheet ensures accurate sensing of the temperature of the piston 1 by the temperature control switch 24 and avoids damage to the heat insulation effect of the heat insulation plate 21, ensuring that the chip 22 and the battery are in a low-temperature operating environment.

[0045] In other examples of this embodiment, the temperature measuring point structure on the surface of piston 1 is adapted to temperature sensor 5: If the temperature measuring point is a stepped hole 11, the diameter of the large hole can be set to φ4 and the axial length of the large hole section to 4mm, the diameter of the small hole can be set to φ2.5 and the axial length of the small hole section to 4mm, and the temperature sensor 5 is an adapted stepped cylindrical shape with an outer diameter of φ3.9 and an axial height of 4mm at the large end, an outer diameter of φ2.4 and an axial height of 4mm at the small end. After the temperature sensor 5 is installed in the hole, the gap between it and the hole wall is filled with high-temperature resistant adhesive for fixation, with a temperature resistance ≥200℃; If the temperature measuring point is an internally threaded hole, it can be set to an M5 internal thread, and the tail of the temperature sensor 5 is provided with an M5 external thread. Fixation is achieved by thread engagement, and the thread mating surface is coated with high-temperature resistant anti-loosening adhesive, with a temperature resistance ≥250℃. The two installation methods, namely the stepped hole 11 with high-temperature adhesive and the internal thread with anti-loosening adhesive, can be adapted to pistons 1 with different structures. This ensures that the temperature sensor 5 does not fall off under high temperature and high pressure environments, while also exposing the temperature measuring part on the surface of the piston 1 to ensure accurate temperature measurement.

[0046] It should be noted that the head of temperature sensor 5 is the temperature measuring end, and its material is the same as that of piston 1, with the end face flush with the surface of piston 1. Using the same material for the measuring end as piston 1 avoids temperature measurement errors caused by differences in thermal conductivity between different materials; the flush end face with piston 1 prevents interference from combustion chamber airflow, further improving measurement accuracy. The external dimensions of temperature measuring module 2 can be customized according to the internal combustion engine model. For example, the temperature measuring module 2 adapted to piston 1 of a 1.5T four-cylinder engine can be 20mm × 15mm × 8mm. A safety clearance must be reserved between its outer circumference and the movement trajectory of the cylinder bore, connecting rod, and crankshaft to avoid motion interference. Specifically, a stainless steel corrugated tube can be fitted around the wire to prevent friction and wear between the wire and the channel wall during the high-speed reciprocating motion of piston 1.

[0047] In other embodiments, the temperature sensor is replaced with a high-temperature pressure transmitter (such as a piezoelectric pressure transmitter adapted to environments above 300°C). By adjusting the pre-programmed program in the chip (changing the data acquisition and signal processing algorithm while retaining the wireless transmission function), the installation structure, heat insulation protection, and temperature control logic of this device can be used to achieve pressure testing in harsh environments such as high temperature and high speed motion (such as combustion pressure testing at the top of a piston).

[0048] Example 2:

[0049] This embodiment provides a method for real-time testing of piston temperature, which utilizes the aforementioned device for real-time piston temperature testing. The testing method includes the following steps:

[0050] (a) Install at least one temperature sensor at a temperature measuring point on the surface of the piston, fix the temperature measuring module to the bottom of the piston pin seat, and electrically connect the temperature sensor and the chip of the temperature measuring module through a wire through the internal channel of the piston.

[0051] (b) Assemble the complete engine in accordance with the technical requirements for internal combustion engine installation, and transfer the complete engine to the test bench or vehicle;

[0052] (c) Place the signal receiver outside the internal combustion engine and connect the signal receiver to the host computer to establish a wireless temperature signal transmission link;

[0053] (d) Start the internal combustion engine. When the temperature control switch in the temperature measurement module senses that the temperature transmitted by the piston reaches 60°C, the temperature control switch conducts the circuit between the high-temperature resistant battery and the chip, and the temperature measurement module starts and begins to collect the temperature data transmitted by the temperature sensor.

[0054] (e) Set the operating conditions of the internal combustion engine according to the test requirements, and collect and record piston temperature data and internal combustion engine operating signals synchronously through the host computer;

[0055] (f) After the test is completed, the internal combustion engine is stopped. When the temperature transmitted by the piston sensed by the temperature control switch is lower than the 50°C reset threshold, the temperature control switch disconnects the circuit and the system returns to the shutdown state.

[0056] The apparatus and method of this specific embodiment, through reasonable structural design and testing process, realizes real-time and accurate temperature testing of internal combustion engine pistons, solving the problems of existing technologies being unable to dynamically measure temperature and having large errors. It has advantages such as high testing accuracy, strong adaptability, and convenient operation, and can be widely used in bench tests or vehicle tests for internal combustion engine research and development.

[0057] Set the operating conditions of the internal combustion engine according to the test requirements. During the test, refer to the test condition parameter table shown in Table 1 to analyze the influence of different operating boundaries on piston temperature. Each operating condition is tested for 15-20 minutes. Piston temperature data and internal combustion engine operating signals (including engine speed, torque, throttle opening, exhaust temperature, and coolant temperature) are collected and recorded synchronously by the host computer.

[0058] Table 1 Test Condition Parameters

[0059]

[0060] Note: In the table, "N, N1~Nn" represent different engine speeds, "M1~Mn" represent different torque values, "A1~An" represent different throttle openings, "F1~Fn" represent different ignition timings, and "E1~En" represent different EGR rates; "Controlling the same BMEP" means adjusting the torque to keep the engine's mean effective pressure consistent, thus eliminating the interference of load differences on the thermal load.

[0061] The method also includes a calibration step before testing: ① Send the temperature sensor separately to a qualified metrology institution for temperature verification to ensure that the sensor error is ≤ ±0.5℃; ② Place the piston equipped with the temperature sensor and temperature measurement module into the constant temperature furnace, and set the furnace temperature to 100℃, 200℃ and 300℃ respectively. Compare the temperature data collected by the host computer with the set temperature data of the constant temperature furnace to correct the measurement error of the test system to ≤ ±1℃.

[0062] The apparatus and methods in Examples 1 and 2 are not only applicable to the temperature testing of internal combustion engine pistons, but can also be extended to other high-temperature, high-speed moving mechanical components, such as gas turbine blades and compressor pistons. If combined with high-frequency acquisition sensors (such as K-type thermocouples with a sampling frequency ≥100Hz) and chip modules that support high-frequency transmission, high-precision measurement and acquisition of instantaneous combustion temperature in the cylinder and transient temperature changes of components can be further realized, providing technical support for the performance evaluation of components under more extreme working conditions.

[0063] Those skilled in the art will recognize that numerous variations are possible with respect to the above description, and the embodiments and figures are merely for describing one or more specific implementations.

[0064] Although exemplary embodiments of the invention have been described and illustrated, those skilled in the art will understand that various changes and substitutions can be made thereto without departing from the spirit of the invention. Furthermore, many modifications can be made to adapt specific situations to the doctrine of the invention without departing from the central concepts of the invention described herein. Therefore, the invention is not limited to the specific embodiments disclosed herein, but may include all embodiments and equivalents that fall within the scope of the invention.

Claims

1. A device for real-time testing of piston temperature, characterized in that, include: At least one temperature sensor is installed at a temperature measuring point on the piston surface. The temperature measuring part of the temperature sensor is exposed on the piston surface and has a built-in K-type thermocouple. A temperature measuring module is installed at the bottom of the piston pin seat. The temperature measuring module includes a heat insulation plate, a chip, a high-temperature resistant battery, and a temperature control switch. The heat insulation plate is in contact with the bottom of the pin seat to isolate the heat transferred by the piston. The chip is used to receive the temperature data transmitted by the temperature sensor and convert it into a wireless temperature signal. The high-temperature resistant battery powers the chip. The temperature control switch is located between the high-temperature resistant battery and the chip to sense the temperature transmitted by the piston, thereby controlling the circuit connection between the high-temperature resistant battery and the chip; the temperature sensor is connected to the chip via a wire passing through the internal channel of the piston to transmit temperature data. A signal receiver, located outside the internal combustion engine, is used to receive the wireless temperature signal sent by the temperature measurement module; The host computer is connected to the signal receiver and is used to convert the wireless temperature signal into temperature values ​​and display and record them.

2. The device for real-time testing of piston temperature according to claim 1, characterized in that, The temperature measuring module is detachably fixed to the bottom of the piston pin seat by screws, and the exposed circuit, solder joints and wires of the temperature measuring module are all filled with high-temperature resistant sealant, the temperature resistance of which is not less than 300℃.

3. The device for real-time testing of piston temperature according to claim 1, characterized in that, The chip is a multi-channel data acquisition chip that can simultaneously receive measurement data from 8-16 channels of the temperature sensors. The frequency of the wireless temperature signal output by the chip can be adjusted by a preset program, with an adjustment range of 1Hz-10Hz.

4. The device for real-time testing of piston temperature according to claim 1, characterized in that, The temperature control switch is a bimetallic strip temperature control switch with a temperature trigger threshold of 60°C. When the sensed piston temperature reaches 60°C, the circuit is turned on, and when the temperature is below 50°C, the circuit is turned off.

5. The device for real-time testing of piston temperature according to claim 4, characterized in that, The temperature control switch achieves heat conduction through a metal heat-conducting sheet and the bottom of the pin seat. One end of the metal heat-conducting sheet is tightly attached to the outer shell of the temperature control switch, and the other end passes through the heat insulation plate and contacts the bottom of the pin seat.

6. The device for real-time testing of piston temperature according to claim 1, characterized in that, The temperature measuring point structure on the piston surface is adapted to the temperature sensor. The temperature measuring point is a stepped hole, and the temperature sensor is fixed to the hole wall by high-temperature resistant adhesive.

7. The device for real-time testing of piston temperature according to claim 1, characterized in that, The temperature measuring point structure on the piston surface is adapted to the temperature sensor. The temperature measuring point is an internal threaded hole, and the tail of the temperature sensor is provided with an external thread, which is fixed by screwing the threads together.

8. The device for real-time testing of piston temperature according to claim 1, characterized in that, The head of the temperature sensor is the temperature measuring end. The material of the head is the same as that of the piston, and the end face of the head is flush with the surface of the piston to ensure accurate temperature measurement.

9. The apparatus for real-time testing of piston temperature according to claim 1, characterized in that, The internal channel of the piston is either a lubricating oil channel built into the piston or a specially machined wire channel; the inner wall of the wire channel is provided with a high-temperature resistant insulating layer, and after the wire is inserted into the channel, the gap between the channel and the wire is filled with high-temperature insulating glue.

10. A method for real-time testing of piston temperature, comprising using the apparatus for real-time testing of piston temperature according to any one of claims 1 to 9, characterized in that, The testing method includes the following steps: (a) Install at least one temperature sensor at a temperature measuring point on the surface of the piston, fix the temperature measuring module to the bottom of the piston pin seat, and electrically connect the temperature sensor and the chip of the temperature measuring module through a wire through the internal channel of the piston. (b) Assemble the complete engine in accordance with the technical requirements for internal combustion engine installation, and transfer the complete engine to the test bench or vehicle; (c) Place the signal receiver outside the internal combustion engine and connect the signal receiver to the host computer to establish a wireless temperature signal transmission link; (d) Start the internal combustion engine. When the temperature control switch in the temperature measurement module senses that the temperature transmitted by the piston reaches 60°C, the temperature control switch conducts the circuit between the high-temperature resistant battery and the chip, and the temperature measurement module starts and begins to collect the temperature data transmitted by the temperature sensor. (e) Set the operating conditions of the internal combustion engine according to the test requirements, and collect and record piston temperature data and internal combustion engine operating signals synchronously through the host computer; (f) After the test is completed, the internal combustion engine is stopped. When the temperature transmitted by the piston sensed by the temperature control switch is lower than the 50°C reset threshold, the temperature control switch disconnects the circuit and the system returns to the shutdown state.

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