JP5222688B2 - Temperature measuring sensor and manufacturing method thereof - Google Patents

Description

  The present invention relates to a sensor for measuring a gas temperature. More particularly, the present invention relates to a sensor that measures the temperature of exhaust gas of an internal combustion engine.

  The background of the present invention is as follows.

  The invention of Patent Document 1 is composed of a ceramic heater in which a heating element is embedded and a ceramic insulating plate to which a thermocouple is fixed, and the tip fixing portion of the thermocouple is fixed inside a groove formed in the ceramic heater. In this structure, an inorganic adhesive is used as a method for fixing the thermocouple to the ceramic heater.

  In the invention of Patent Document 2, an insulating layer is formed of alumina, glass or plastic on the surface of a thin film thermocouple or thin film resistor formed on a substrate, and a metal or conductive ceramic is used as a shield layer in the main part. It is a structure in which a layer is provided.

JP 2004-296358 A Japanese Patent Laid-Open No. 2-171626

  As a measure to prevent global warming, reducing the amount of fossil fuel used in automobiles to reduce carbon dioxide emissions is a proposition of the automobile industry, and the development of diesel engines and fuel-efficient gasoline engines I'm in a hurry. As a countermeasure, diesel engines and gasoline engines tend to cope by improving the accuracy of combustion control. As information indispensable for improving the accuracy of the combustion control, the temperature of the combustion gas passing through each part of the internal combustion engine is important. However, since the temperature of the combustion gas itself is a high temperature range of 400 ° C. to 800 ° C. and the combustion gas itself is a corrosive gas fluid such as SOx, NOx, COx, a temperature sensor is used as a countermeasure against high temperature oxidation and corrosion. Due to the structure completely covered with corrosion-resistant stainless steel, there was a drawback of poor thermal response.

  To increase the accuracy of combustion control in internal combustion engines, it is important to detect the temperature of the gas flowing through each part in real time and to provide detailed combustion control by feeding back the combustion state. If the thermal response of the signal is slow, the control error increases and the intended control cannot be performed.

  In reality, with the temperature sensors currently listed, there is no product that can be used due to the slow thermal response of high-precision combustion control.

  The present invention is a gas temperature sensor for internal combustion engines, such as automobile exhaust gas, EGR gas, combustion gas, exhaust gas before and after DPF, etc., and a temperature sensor with high thermal responsiveness while guaranteeing high temperature oxidation and corrosion resistance. It can be invented.

  The above object can be achieved by the invention described in the claims.

For example above object, Oite temperature Sensor for detecting the temperature by the thermocouple, said thermocouple, the low-temperature co-fired substrate (LTCC), 2 sheets of inorganic sandwiched therebetween and the low-temperature co-fired substrate and the thermocouple comprising a member substrate, the interface between the said low-temperature firing substrate the two inorganic member substrate, is more adhered to the low temperature sintering substrate,
Metals that provide adhesion reactivity with the inorganic substrate to each of the temperature sensors that are the low-temperature fired substrate, glass, and inorganic adhesive as members for fixing the thermocouple to the inorganic member substrate more is achieved temperature sensor, characterized in that blended with oxides.

  According to the present invention, as a temperature sensor for an internal combustion engine, such as automobile exhaust gas, EGR gas, combustion gas, exhaust gas before and after DPF, etc., a temperature sensor with high thermal responsiveness while guaranteeing high temperature oxidation and corrosion resistance Can be provided.

  This will be described in detail below.

  Before describing the features of the present invention, an internal combustion engine for an automobile will be described. Here, a diesel engine will be described briefly. FIG. 1 shows a general diesel engine 1. The system is a system in which intake air 2 is combusted when air whose flow rate is adjusted by a throttle valve 3 installed upstream of the intake manifold is sent to the cylinder 4 and compressed by the cylinder 4. The combustion gas 5 branches through the exhaust pipe 6. One is sent to the turbocharger 7 and output is added by the supercharger. The combustion gas 5 discharged from the turbocharger 7 passes through a purification device (DPF) 8 provided with a catalyst as exhaust gas, and is discharged to the outside as clean air. On the other hand, the non-burning gas in the combustion gas 5 is re-refluxed to the cylinder 4 again, thereby reducing the NOx and SOX components contained in the unburned components. There is a bypass pipe that is provided in a part of the exhaust pipe 6 and flows the combustion gas 5, and the flow rate of the combustion gas 5 is controlled by the EGR valve through the bypass pipe 9. Since the temperature of the combustion gas 5 as the exhaust gas is as high as 400 ° C. or higher, the gas temperature is lowered to 200 ° C. or lower through the EGR cooler. This system is sent to the downstream of the throttle valve 3 through the EGR recirculation pipe and burned in the cylinder 4 again, which greatly contributes to the purification of exhaust gas.

  The key components used in this diesel system are an air flow meter 12, an intercooler 13, a throttle valve 3, an EGR valve 10, an EGR cooler 11, a turbocharger 7, a DPF 8, and the like. In the diesel system, EGR is a gasoline engine. Since the flow rate is larger and the recirculation is intentionally performed by EGR, the reliability of each part is important.

  In particular, the diesel engine 1 uses light oil as the fuel, so the ignition point of the fuel is high, and the combustion gas tends to generate not only completely burned gas but also unburned gas. In the state where NOx, SOx, and COx are mixed in the unburned gas, the components change every moment according to changes in the operating state and the environmental state. Further, the unburned gas and the exhaust gas are corrosive gas because NOx, SOx, and COx are mixed, and special metals and inorganic members tend to be used because general members are not used.

  In addition, the temperature of exhaust gas and unburned gas, which are combustion gases, varies depending on the operating conditions and environmental conditions, but is said to be 400 ° C to 900 ° C for exhaust gas and 600 ° C or higher for unburned gas. Therefore, special metals and inorganic members are used.

  In recent years, regulations on exhaust gas have been strengthened, so each car manufacturer is considering improvements to exhaust clean exhaust gas from which NOx and SOx have been removed from the exhaust gas. As a method that can be most easily realized, the concept of the system of the current diesel engine 1 is to realize a system that can perform combustion control with higher accuracy as it is. An example of the high-precision combustion control system is the system configuration shown in FIG.

  In FIG. 2, there is no change in the combustion system itself of the diesel engine. However, there is a change point in that the gas temperature sensor 17 is provided in each part of the system. The gas temperature sensor 17 is an existing product, and is an exhaust gas temperature sensor 17 that is attached to an exhaust pipe mainly for exhaust gas temperature measurement and measures the temperature of the exhaust gas. The main function was a temperature monitor.

  In the high precision control system, as described above, the gas temperature sensor 17 is provided in each part of the system, so that the combustion state of each part can be monitored.

  However, current exhaust temperature sensors are difficult to handle. The reason for this will be described later.

  In addition to the exhaust pipe, the gas temperature sensor 17 is provided at the front and rear positions 14 of the DPF 8 in the diesel system. By using the gas temperature sensor 17 before and after the DPF 8, it is possible to check the catalytic activity state of the DPF 8, and it can be a control sensor for the DPF 8 catalyst.

  Similarly, a gas temperature sensor 17 may be provided at the front-rear position 15 of the EGR cooler 11 to control the active state of the EGR cooler. A gas temperature sensor 17 that measures the gas temperature itself may be attached to the EGR valve 10 position 16.

  That is, by providing the gas temperature sensor 17 at each site where the gas fluid of the diesel engine 1 flows, the state of the exhaust gas purification system and the cooling device can be a secondary signal that can further confirm the combustion state. Thus, by monitoring the gas temperature of each part, it can be a system capable of performing more accurate combustion control.

  However, the gas temperature sensor 17 for the internal combustion engine currently listed has many restrictions because it is an environmental condition as described above, a corrosive gas such as NOx and SOx, and a high temperature environment exceeding 400 ° C. It is a difficult sensor for manufacturers.

  FIG. 3 shows the structure of a gas temperature sensor 17 for measuring a general exhaust temperature currently listed.

  In general, the thermistor 18 is often used as the gas temperature sensor 17. Since the signal wire 19 extending from the thermistor 18 has a temperature of 400 ° C. or higher, it is a lead that becomes the signal wire 19 made of a heat-resistant and corrosion-resistant material such as platinum, a platinum alloy, or stainless steel. The signal line 19 is extended as it is, and the signal line 19 is extended through a hole formed in the sheath tube 20 made of an inorganic material to prevent contact and cope with vibration resistance. Further, the signal line 19 is extended to the outside through a grommet 21 made of heat-resistant rubber. The signal line 19 is welded and crimped with a normal copper wire in the vicinity of the grommet 21 and transmits a signal to the ECU.

  The grommet 21 and the sheath tube 20 are fixed by being installed in a flange tube 23 that is made of a heat-resistant and corrosion-resistant member that covers the outer periphery of the grommet and is positioned and a fixing screw is cut. The Since the thermistor 18 of the gas temperature sensor 17 cannot be exposed in the exhaust gas, the thermistor 18 is covered with a cylindrical bag tube 24 that covers the thermistor 18 and the contact portion with the flange tube 23 is welded.

  The structure is simple and the heat resistant structure is excellent, but there are two problems.

  One is the narrow temperature measurement range. FIG. 4 shows the characteristics of the thermistor sensor currently listed. The advantage of the thermistor is that it can be measured with low cost, high temperature resolution and high accuracy, but the specification required for the thermistor 18 used in the internal combustion engine is 900 ° C. compatible. In the current technology, the thermistor chip that can measure the upper limit of 900 ° C with a thermistor has a resistance value expression resolution of 0.5-1 (Ω) and an upper limit of 900 ° C or higher near 800 ° C, making temperature measurement impossible. Become. Conversely, at room temperature, it is approximately 10 (kΩ) or more. Below this temperature, the resistance value is almost megohm, that is, the resistance is open, and temperature measurement is impossible. Therefore, the temperature measurement range of the temperature sensor using the thermistor 18 seems to be the limit of 200 to 800 ° C. in consideration of accuracy, and the car manufacturer who wants to measure the temperature up to 1200 ° C. does not comply with the specification.

  Second, a temperature measuring element such as a thermistor is not in direct contact with the gas fluid, but is propagated through the bag tube 24 and through the air layer 25 between the bag tube 24 and the thermistor 18. Therefore, there is a drawback that the thermal response when the gas temperature changes is slow.

  In addition, there has been a case where a thermocouple is inserted in the bag tube 24 as a temperature measurement sensor instead of the thermistor 18 from the past.

  In the present invention, a structure capable of providing a temperature sensor capable of solving the above-described performance problems of the general gas temperature sensor 17 has been invented.

  Details of the present invention will be described with reference to FIGS.

  In the present invention, the temperature measuring element is modeled on the thermocouple 26, but it should be noted that this can be applied to all temperature measuring sensors, whether a thermistor or a thin film resistor. In the present invention, a thermocouple 26 is used as a temperature sensor, for the reason shown in FIG. Although there are various thermocouples 26, it is obvious that a chromel-alumel (K) thermocouple or a platinum-platinum / rhodium (R) thermocouple is used in consideration of the temperature range used in an internal combustion engine. . The advantage of the thermocouple 26 lies in the wide measurement temperature range that can be measured from a low temperature to a high temperature. For example, K thermocouples are capable of measuring temperatures up to 1000 ° C in class 3, but practically 900 ° C is the limit. On the other hand, since the R thermocouple shown in FIG. 7 is an alloy of platinum and platinum / rhodium, its normal heat resistance reaches 1400 ° C. In recent years, as a requirement for car manufacturers, there is a demand for measuring higher temperatures, and an R thermocouple is suitable if considering 1200 ° C. support. Since platinum and platinum / rhodium alloys are both noble metals, they are less susceptible to oxidative degradation due to high temperatures than any other metal, and are suitable as gas temperature sensors for automobile internal combustion engines. FIG. 7 shows the relationship between the temperature of the R thermocouple and the temperature generated electromotive force. A thermocouple generates an electromotive force when a temperature difference between two different metals is melted. This electromotive force characteristic is 0 (V) at 0 ° C., and the electromotive force becomes positive as the temperature increases. It changes linearly to the direction output. On the other hand, when the temperature becomes lower, the generated electromotive force is generated as a negative signal. Although it is difficult to reduce the temperature resolution, the traceability of the thermocouple itself is ensured, so there is no problem in measurement accuracy. In general, R thermocouples are calibrated for temperatures from 0 ° C. to 1600 ° C., and there is no calibration table at minus temperatures. This is because there is no industrial need to use an expensive R thermocouple to measure a negative temperature, and the calibration of the negative side of the R thermocouple can be performed without any problem by requesting it from a calibration organization. it can.

  From here, the structure of the gas temperature sensor 17 of this invention is introduced.

  The thermocouple 26 is made of an inorganic member made of the same member, and is a LTCC (low temperature fired substrate) green sheet between two substrates 27 made of silicon nitride, aluminum nitride, alumina, sialon or the like. , Sandwiched with glass, then fired. Alternatively, the inorganic adhesive member 28 is bonded and fixed.

  For the substrate 27 that has been baked, the thermocouple lead 29 coming out of the substrate 27 sandwiching the thermocouple 26 is used for the purpose of preventing contact and heat insulation of the thermocouple lead 29 made of the inorganic adhesive member 28. The sheath tube 20 is penetrated. Further, after passing through a grommet 21 made of silicone and fluorine-based heat-resistant rubber, it is mounted in a flange pipe 23 in which a positioning flange 22 and a screw for fixing a measurement position are cut. The flange 22 and the flange tube 23 have heat resistance and corrosion resistance and are positioned in the flange tube inner 23 made of stainless steel, nickel base alloy or the like, and the gap between the flange tube 23 and the substrate 27 is filled and the substrate is fixed to the flange tube. The inorganic filler 30 is filled.

  The thermocouple lead 29 is connected to the guarantee copper wire 31 in the vicinity of the grommet 21 and transmits a temperature signal through the guarantee copper wire 31.

  In order to improve the thermal response, the present invention is characterized in that it is a temperature sensor having a sensing unit that can expose a substrate 27 sandwiched by a thermocouple 26 to a gas flow to be measured. Therefore, since this substrate is an inorganic member having high thermal conductivity such as silicon nitride, aluminum nitride, and sialon, a substrate material having both heat resistance and corrosion resistance is employed.

  Silicon nitride is suitable as a material having high bending strength, high thermal conductivity and good balance. Since the gas temperature sensor 17 that measures the gas temperature of each part of the internal combustion engine is intended to improve the thermal response, it is important to have a high thermal conductivity of the substrate and to reduce the heat capacity. Since the strength of silicon nitride is about twice that of alumina, it is possible to reduce the heat capacity by making the substrate thinner. Furthermore, a silicon nitride substrate having a thermal conductivity approximately three times that of alumina makes it possible to instantaneously transmit the occurrence of temperature change to the thermocouple, thereby providing a temperature sensor having a sensing portion with high thermal followability.

  Furthermore, since inorganic members containing silicon nitride and aluminum nitride do not corrode at all in corrosive gas atmospheres such as acid resistance and chemical resistance, they are chemically and physically stable materials. No change occurs when 27 comes in contact with the combustion gas 5 and EGR gas. Because of this excellent stability, long-term reliability can be secured because there is no risk of damage or corrosion of the substrate itself even when exposed to combustion gas 5 or EGR gas. Since the thermocouple 26 is made of platinum-platinum rhodium alloy, it is more resistant to corrosion such as oxidation and sulfidation than ordinary metals, but when exposed to SOx gas environment exceeding 800 ° C, platinum is sulfided. Begins and PtS is formed. Therefore, exposing the thermocouple 26 to a corrosive gas may impair long-term reliability and cause a thermocouple electromotive force error. In the present invention, since it is in a space completely sealed from the two silicon nitride substrates 27 and LTCC, it does not come into contact with the gas to be measured, but when the measurement fluid comes into contact with the silicon nitride substrate, In order to instantly transfer the temperature of the entire substrate including the pair, it becomes a sensing part of a temperature sensor that combines thermal response and long-term reliability including corrosion reliability.

  The structure of the sensing part of the temperature sensor sandwiching the thermocouple 26 will be described with reference to FIG. The thermocouple 26 is welded at the tip, and forms so that the thermocouple lead 29 other than the welded portion does not come into contact. Then, a thermocouple 26 is installed on the surface of the inorganic substrate 27. In the installation portion of the thermocouple 26, the vicinity of the center portion of the substrate 27 is advantageous from the viewpoint of thermal response. Positioning the thermocouple 26 on the surface seems unstable, but the reality is different. Since the shape is fixed after the thermocouple is formed, positioning is more stable than a method of burying in a groove formed on the substrate surface 27 or a method of passing a hole. It suffices if the tip welding part, which is the temperature measuring part of the thermocouple 26, is in the vicinity of a predetermined position of the substrate 27. Next, the LTCC green sheet 32 which becomes the adhesive agent for the board | substrate 27 and the board | substrate 27 is mounted. The LTCC green sheet 32 is a sheet-like pre-fired substrate in which a mixture of alumina and glass before firing is kneaded with an organic binder. In the present invention, the LTCC green sheet 32 is sandwiched between the substrate 27 and the substrate 27 and fired. Thus, the interface between the LTCC green sheet 32 and the substrate 27 is utilized as an adhesive that adheres by vitrification at the interface. In the present invention, the LTCC green sheet 32 is processed along the shape of the portion of the thermocouple 26 that passes through the lead 29, and a contact prevention sheet is also installed between the thermocouple leads 29. The green sheet 32 may be covered as it is. Then, it is covered with the same substrate 27 as the lower substrate 27, and is fired at a temperature at which the LTCC green sheet 32 is fired in this state, thereby fixing the thermocouple 26 and bonding the two substrates 27 together. Will work. In addition to LTCC, there is a glass sheet as a member that bonds substrate 27, but there are many non-heat-resistant glasses such as soda lime glass, and manufacturers that supply tempered glass such as crystallized glass as a sheet. The inventor does not recognize. Other common adhesive members include inorganic adhesives. There are many types and grades, and it is better to use them after confirming the combination.

  The result of measuring the thermal response by making a temperature sensor with a structure in which the completed thermocouple 26 is sandwiched between the substrates 27 will be described below. The thermocouple was R type and linear φ0.15 was used. The substrate used was a silicon nitride substrate made by Hitachi Metals. Thickness: 0.2 mm, width 6 mm, length 25 mm. As the adhesive, an LTCC green sheet having a thickness after firing of 0.14 was used. Using the temperature sensor of this specification, the thermal response time (63%) when the temperature was suddenly changed from room temperature to 600 ° C. was 6 seconds. In a similar test, since the thermistor is put in a bag tube and the temperature sensor of the type is 14 seconds, the structure of the present invention can be a product suitable as a gas temperature sensor for an internal combustion engine that enables a high-speed response.

  In the embodiment of the present invention, an example in which an inorganic member having high conductivity such as silicon nitride, aluminum nitride, and sialon is suitable for the substrate 27 that protects the thermocouple 26 from corrosion has been shown. However, aluminum nitride has problems. This is because the compatibility with the LTCC green sheet 32, the glass, and the inorganic adhesive that sandwich and fix the thermocouple 26 is poor. In general, inorganic adhesives are bonded by reacting with the oxide of the adherend, even if glass, but since there is no functional group that reacts with the adhesive on the nitride surface, glass or inorganic adhesives are used. The system adhesive cannot wet and spread, and is cured in the form of droplets even when a temperature is applied in a droplet state on the nitride film surface.

In the present invention, as shown in FIG. 9, an oxide film 33 is applied on the surface of silicon nitride or aluminum nitride, thereby improving adhesion with the LTCC green sheet 32, glass, and inorganic adhesive. Specifically, this can be achieved by forming an oxide film 33 such as alumina (Al ₂ O ₃ ) or silica (SiO ₂ ) on the surface of the substrate 27. The deposited film can form an oxide film 33 with stable sputtering and plasma radiation. A thickness of 1 μm is sufficient.

As another method, there is a method in which a metal oxide is blended in the LTCC green sheet 32 and bonded by causing a chemical reaction with the nitride film surface during firing. Copper oxide (CuO), cuprous oxide (Cu ₂ O), boron oxide (B ₂ O ₃ ), zinc oxide (ZnO), nickel oxide (NiO) and the like are typical metal oxides, and these are fired. Adhesion by a mechanism that adheres (adheres) by chemically reacting with impurities contained in the substrate and some metal components and forming a crystal or crystal at the substrate / adhesive interface. Adhesion can be improved even with a nitride film that is difficult to resist.

  It is also effective to develop a surface oxide film by heating a single substrate to 1000 ° C. or higher before bonding.

As an example, Hitachi Metals Co., Ltd.'s silicon nitride substrate was temporarily fired at 1200 ° C and a substrate without heat treatment, and it was confirmed that it was bonded as a result of firing with the LTCC green sheet still on the substrate surface. It is clear from the fact that the area that can be obtained has doubled. In particular, in the case of silicon nitride, since there is silicon (Si) in the crystal, by partially thermally decomposing the crystal with this nitride, it is due to a silicate phenomenon in which SiO ₂ precipitates. It is clearer than the research report.

  FIG. 10 shows that in the present invention, the substrate 27 is exposed to expose the substrate 27 sandwiched with the thermocouple 26 serving as the temperature sensing unit in the gas, but the exposure of the sensing may not be preferred. This is because there is a concern that the gas temperature sensor 17 may be broken by being hit by a hard pipe part during the mounting operation of the gas temperature sensor 17. In such a case, the protector 34 shown in FIG. 10 may be formed to cover the sensing. The protector 34 is at least a heat-resistant, corrosion-resistant material, stainless steel or a nickel-based alloy plate, and is formed into a deep hole with a collar. Then, there is a through hole 35 in a part of the cylindrical portion, and a positional relationship is maintained such that the through hole 35 and the thermocouple 26 portion of the gas temperature sensor 17 coincide with each other, and the collar portion is welded to the flange tube 23. Since it becomes a protective tube that does not destroy the sensing even in handling, and a structure in which the gas fluid is directly brought into contact with the sensing, it becomes a structure that can cope with a handling mistake while reducing a delay in thermal response.

  FIG. 11 shows signal processing. Since the electromotive force characteristic of the thermocouple 26 is 0 (V) at 0 ° C., the thermocouple electromotive force at the negative temperature is a negative signal. Therefore, it becomes difficult to handle signals in automobile control. Therefore, the electromotive force 36 of the thermocouple is input to the computing unit 37, the negative signal is inverted, and a linear characteristic as a whole is output. For example, by setting it to 0 (V) at -50 ° C and adjusting it with a calculator so that an output of 5 (V) is obtained at 1400 ° C, the signal form can be easily processed by the microprocessor of the internal combustion engine. Ease of use as a system is manifested. It is preferable to install this calculator inside the microprocessor rather than the vicinity of the temperature sensor installation portion where high temperature or corrosive gas is filled.

  According to the present invention, it can be expected that the temperature of each part gas fluid of the internal combustion engine can be supplied with a temperature sensor that has a quick thermal response and can guarantee long-term reliability that also serves as corrosion resistance.

Diesel engine system. Gas temperature sensor mounting part. General exhaust temperature sensor structure. Thermistor characteristics used in general exhaust temperature sensors. The temperature sensor structure (side view) of this invention. The temperature sensor structure (front view) of this invention. The electromotive force characteristic of the thermocouple used in the present invention. The assembly drawing of the temperature sensor sensing part of this invention. Oxidation treatment to the substrate surface. The temperature sensor of the present invention with a protector. Signal processing diagram.

Explanation of symbols

1 Diesel Engine 2 Intake Air 3 Throttle Valve 4 Cylinder 5 Combustion Gas (EGR Gas)
6 Exhaust pipe 7 Turbocharger 8 DPF
9 Bypass pipe 10 EGR valve 11 EGR cooler 12 Air flow meter 13 Intercooler 14 DPF longitudinal position 15 EGR cooler longitudinal position 16 EGR valve position 17 Gas temperature sensor 18 Thermistor 19 Signal line 20 Sheath pipe 21 Grommet 22 Flange 23 Flange pipe 24 Bag pipe 25 Air Layer 26 Thermocouple 27 Substrate 28 Inorganic Adhesive Member 29 Thermocouple Lead 30 Inorganic Filler 31 Guaranteed Copper Wire 32 LTCC Green Sheet 33 Oxide Film 34 Protector 35 Through Hole 36 Thermocouple Electromotive Force 37 Calculator 38 Output Signal

Claims (9)

In a temperature sensor that detects the temperature with a thermocouple,
The thermocouple;
A low-temperature fired substrate (LTCC);
Two inorganic member substrates sandwiching the thermocouple and the low-temperature fired substrate;
With
The interface between the low-temperature fired substrate and the two inorganic member substrates is bonded by vitrification of the low-temperature fired substrate ,
Metals that provide adhesion reactivity with the inorganic substrate to each of the temperature sensors that are the low-temperature fired substrate, glass, and inorganic adhesive as members for fixing the thermocouple to the inorganic member substrate A temperature sensor characterized by containing an oxide . In claim 1 ,
The low-temperature co-fired substrate, the temperature sensor, characterized in that it comprises alumina and glass. In claim 1 ,
A temperature sensor characterized in that the substrate is formed with an oxide film on the surface or subjected to a surface oxidation treatment on the entire surface or a part thereof. In claim 1 ,
The temperature sensor according to claim 1, wherein the substrate is an inorganic member having a thermal conductivity higher than that of alumina, at least of silicon nitride, aluminum nitride, and sialon. In claim 1 ,
The temperature sensor according to claim 1, wherein the thermocouple is a thermocouple made of platinum and a platinum rhodium alloy, or a thermocouple made of chromel or alumel. The temperature sensor according to claim 1, wherein the thermocouple is a member that fixes the thermocouple to the substrate made of an inorganic material, such as LTCC (low-temperature fired substrate), glass, and an inorganic adhesive. A temperature sensor comprising a metal oxide that gives adhesion reactivity. In claim 1 ,
The temperature sensor characterized in that the substrate has a semicircular cross section, a thermocouple is sandwiched between the semicircular flat portions, and the semicircular flat portion is used as an adhesive fixing portion. In claim 1 ,
A temperature sensor comprising a cylindrical molded article covering the entire sensor and having a through hole in a part of the sensor as a protective protector of the sensor. The temperature measurement sensor according to any one of claims 1 to 8, which measures an exhaust temperature, an exhaust catalyst temperature, an EGR gas temperature, a gas temperature before DPF, a DPF exhaust gas temperature, or a DPF internal atmosphere temperature of an automobile internal combustion engine. When,
Control means for controlling the internal combustion engine based on the measurement value of the temperature measurement sensor;
An internal combustion engine control system.

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