CN108151895A - A kind of customized transient response temperature sensor of size and preparation method thereof - Google Patents

Abstract

The invention discloses a transient response temperature sensor with customizable dimensions and a preparation method thereof; it is characterized in that it includes: a temperature measuring probe with a coaxial probe structure, which has a first thermal electrode, a cylinder wall and Surrounding the first thermal electrode in the radial direction and forming a thermal junction with the first thermal electrode through a thin film, the second thermal electrode and the insulating layer; one end of the coaxial probe structure is formed with a thin film coating, and the other end The protruding first thermal electrode and the second thermal electrode are respectively connected and fixed to the first thermal electrode compensation wire and the second thermal electrode compensation wire through high-temperature inorganic glue to form a transition section and be loaded into the wire In the protective sleeve; the transition section is partially inserted into the customizable threaded pipe and the outer wall near the temperature measuring end is processed with external threads. The invention has the advantages of small size, simple structure, convenient manufacture, customizable installation size, and can realize the measurement of transient temperature with a response time of microsecond level.

Description

A transient response temperature sensor with customizable dimensions and its preparation method

technical field

The invention belongs to the technical field of sensors, and in particular relates to a transient response temperature sensor with customizable dimensions and a preparation method thereof.

Background technique

Sensing technology is one of the important technologies of modern measurement and automation systems, among which temperature sensors can effectively detect temperature. With the continuous advancement of science and technology, the requirements for temperature measurement technology in various fields are also getting higher and higher. Among them, the measurement of transient temperature occupies an extremely important position, and its development direction also tends to be high temperature and fast and accurate response. Thin-film thermocouple is a kind of transient temperature measurement sensor emerging in modern times. It has typical two-dimensional characteristics. Thermocouple sensors have been significantly improved in terms of volume, materials, and response speed. At the same time, they can perform transient temperature measurement, which has important practical value and broad application prospects.

At present, the common temperature measurement methods are: thermocouple temperature measurement, radiation temperature measurement, thermal resistance temperature measurement, sound wave temperature measurement, etc., but for the temperature measurement of brake discs, high-speed train bearings, shock tubes, etc., these methods It is easily interfered by many factors and cannot meet the requirements of fast and accurate transient measurement.

Contents of the invention

In view of the defects existing in the prior art, the purpose of the present invention is to provide a transient response temperature sensor with customizable dimensions, which has the advantages of small size, simple structure, convenient manufacture, customizable installation dimensions, and transient temperature response. It can improve the connection mode between common thin-film thermocouple compensation wires and electrodes, etc.

In order to achieve the above object, technical scheme of the present invention:

A transient response temperature sensor with customizable dimensions, characterized by comprising:

A temperature-measuring probe having a coaxial probe structure having a first thermal electrode, a cylinder wall formed to surround the first thermal electrode in a radial direction and to communicate with the first thermal electrode A second thermal electrode forming a thermal junction through a thin film, and an insulating layer filling the gap between the first thermal electrode and the second thermal electrode;

One end of the coaxial probe structure is formed with a thin film coating as a temperature measuring end;

The first thermal electrode and the second thermal electrode protruding from the other end of the coaxial probe structure are respectively connected to the first thermal electrode compensation wire and the second thermal electrode compensation wire through high-temperature inorganic glue, and Fixing to form a transition section, while the first thermode compensation wire and the second thermode compensation wire are put into the wire protection sleeve;

The transition section is partially inserted into a customizable threaded pipe, and the outer wall of the customizable threaded pipe near the temperature measuring end is processed with external threads.

Based on the above scheme, further preferably,

The first thermal electrode is a wire-shaped thermal electrode; the second thermal electrode is a cylindrical thermal electrode.

Based on the above scheme, further preferably,

The first thermal electrode and the first thermal electrode compensation wire adopt the same mass percentage of NiSi alloy material; the second thermal electrode and the second thermal electrode compensation wire adopt the same mass percentage of NiCr alloy material.

Based on the above scheme, further preferably,

The thin-film coating consists of a thermal junction film and a protective film coated on the surface of the temperature-measuring end of the temperature-measuring probe.

Based on the above scheme, further preferably,

The insulating layer is composed of insulating ceramics and high-temperature inorganic glue.

Based on the above scheme, further preferably,

The material of the insulating ceramic is nano-ceramic powder, and the high-temperature inorganic glue is double bond DB5012 high-temperature-resistant inorganic glue.

Based on the above scheme, further preferably,

The side of the customizable threaded pipe is equipped with slotted flat-end set screws for fixing the position of the temperature measuring probe, and the length of the temperature measuring probe can be adjusted to a certain extent according to the actual situation.

Another object of the present invention is to provide a method for preparing the above-mentioned transient response temperature sensor with customizable dimensions, which includes:

S1. Cleaning the surface of the first thermal electrode and the second thermal electrode;

S2. Coat the surface of the first thermal electrode with nano-ceramic slurry and put it into a vacuum ceramic furnace for high-temperature sintering. The insulating ceramic preparation process can be repeatedly coated and sintered to the required thickness and shape;

S3. Firstly, the surface of the sintered body formed after the above-mentioned high-temperature sintering treatment is roughly treated, and the high-temperature inorganic glue is coated again, and at the same time, the high-temperature inorganic glue is filled in the second hot electrode; secondly, the first hot electrode and the sintered body are put into the second hot electrode. In the second thermal electrode to form a coaxial probe structure; finally, at the same time, the second thermal electrode compensation wire is closely attached to the wall of the second thermal electrode cylinder, and the position of the first thermal electrode compensation wire and the second thermal electrode compensation wire is adjusted using high-temperature inorganic glue. After fixing, place it in a ventilated place and wait for curing;

S4. Grinding and polishing the surface of the temperature measuring end of the cured temperature measuring probe;

S5, clean the end face of the temperature measuring probe that has been polished, and in a high vacuum coating machine, deposit NiCr thin film and _SiO on the end face of the temperature measuring probe successively by magnetron sputtering Protective film to form the film Plating;

S6. Select a customizable threaded tube according to the customization requirements and put the temperature measuring probe into the customizable threaded tube, so that the two compensation wires are introduced into the wire sheath protective sleeve. After adjusting the length of the temperature measuring probe, slot it with a flat end to tighten it. Fix with set screws.

Compared with prior art, the beneficial effect of the present invention:

The invention has the advantages of small size, simple structure, convenient manufacture, customizable installation size, transient temperature response, and stable and reliable connection between the compensation wire and the electrode. It can be applied to the measurement of the transient temperature of the inner surface of the high-speed brake disc and the piston of the diesel engine, and can also meet the requirements of the measurement of the transient temperature of the shock wave wind tunnel model.

Description of drawings

Fig. 1 is a schematic illustration of the overall structure of the transient response temperature sensor of the present invention;

Fig. 2 is a partial sectional illustration of the temperature measuring probe of the transient response temperature sensor of the present invention;

Fig. 3 is the technological flow diagram of transient response temperature sensor of the present invention;

Fig. 4 is a schematic illustration of the length adjustment of the transient response temperature sensor of the present invention;

Fig. 5 is a schematic diagram illustrating the transient temperature measurement of the brake disc by the transient response temperature sensor of the present invention.

In the figure: 1. Compensation wire for the first hot electrode, 2. High temperature inorganic glue, 3. Insulating ceramics, 4. Second hot electrode, 5. Hot junction film, 6. Protective film, 7. First hot electrode, 8. Flat-end slotted fastening screw, 9. Custom threaded tube, 10. Wire protection sleeve, 11. Second thermal electrode compensation wire.

Detailed ways

In order to make the purpose, technical solutions and advantages of the present invention clearer, the technical solutions of the present invention will be clearly and completely described below in conjunction with the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are part of the implementation of the present invention. example, not all examples. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

As mentioned above, in order to meet the above status quo and development needs, the present invention provides a transient response temperature sensor with customizable dimensions, which can be applied to the measurement of the transient temperature of the inner surface of high-speed brake discs and diesel engine pistons, and can also meet the requirements of exciting conditions. The demand for instantaneous temperature measurement of wave wind tunnel model.

Specifically, a size-customizable transient response temperature sensor as shown in Figures 1-2 is characterized in that it includes:

A temperature-measuring probe having a coaxial probe structure having a first thermal electrode, a cylinder wall formed to surround the first thermal electrode in a radial direction and to communicate with the first thermal electrode A second thermal electrode forming a thermal junction through a thin film, and an insulating layer filling the gap between the first thermal electrode and the second thermal electrode;

One end of the coaxial probe structure is formed with a thin film coating as a temperature measuring end;

The first thermal electrode and the second thermal electrode protruding from the other end of the coaxial probe structure are respectively connected to the first thermal electrode compensation wire and the second thermal electrode compensation wire through high-temperature inorganic glue, and Fixing to form a transition section, while the first thermode compensation wire and the second thermode compensation wire are put into the wire protection sleeve;

The transition section is partially inserted into a customizable threaded pipe, and the outer wall of the customizable threaded pipe near the temperature measuring end is processed with external threads;

Among them, the sensor can adjust the processing length of the temperature measuring probe and the type and length of the threaded pipe that can be customized according to the customization requirements, so as to realize the manufacture of sensors of various lengths, serialize the sensors, and meet the customization requirements of various occasions; its significant advantages It is small in size, simple in structure, easy to manufacture, customizable in installation size, transient temperature response, stable and reliable connection between compensation wire and electrode; The electrical signal is transmitted to the cold junction compensation and signal amplification circuit through the compensation wire, and finally processed by the computer acquisition system to obtain the instantaneous temperature measurement value.

Based on the above scheme, further preferably,

The first thermal electrode is a wire-shaped thermal electrode; the second thermal electrode is a cylindrical thermal electrode.

Based on the above scheme, further preferably,

The first thermal electrode and the first thermal electrode compensation wire adopt the same content ratio, that is, the mass percentage of NiSi alloy material; the second thermal electrode and the second thermal electrode compensation wire use the same content ratio, that is, the mass percentage of the NiCr alloy material.

Based on the above scheme, further preferably,

The thin-film coating is composed of a thermal junction film and a protective film coated on the surface of the temperature-measuring end of the temperature-measuring probe. The electrode constitutes a hot junction, and then a protective film is coated on the film. At the same time, the material of the hot junction film is the same NiCr alloy as the second material of the hot electrode, and the diameter of the hot junction is not more than 0.3mm; the material of the protective film is SiO ₂ films.

Based on the above scheme, further preferably,

The insulating layer is composed of insulating ceramics and high-temperature inorganic glue.

Based on the above scheme, further preferably,

The material of the insulating ceramic is nano-ceramic powder, and the high-temperature inorganic glue is double bond DB5012 high-temperature-resistant inorganic glue.

Based on the above scheme, further preferably,

The side of the customizable threaded tube is equipped with a slotted flat-end set screw, which is used to fix the position of the temperature measuring probe, and the length of the temperature measuring probe can be adjusted to a certain extent according to the actual situation. The preferred customizable threaded tube The material is 304 stainless steel.

Another object of the present invention is to provide a method for preparing the above-mentioned transient response temperature sensor with customizable dimensions, which includes:

S1. Clean the surface of the first thermal electrode, that is, the filamentary thermal electrode-7, and the second thermal electrode, that is, the cylindrical thermal electrode 4, and use deionized water ultrasonic cleaning and acetone and ethanol cleaning to ensure the cleanliness of the surface to be processed ;

S2. Coat the surface of the wire-shaped thermode-7 (the part to be processed into a temperature measuring probe) with nano-ceramic slurry and put it into a vacuum ceramic furnace for high-temperature sintering at 940°C for 10 minutes. The preparation process of the insulating ceramic 3 can be repeated many times Coating and sintering to the required thickness and shape, as shown in Figure 3-①;

S3. First, the surface of the sintered body formed after the above-mentioned high-temperature sintering treatment is roughly treated, and the high-temperature inorganic glue 2 is coated again, and at the same time, the high-temperature inorganic glue 2 is filled in the cylindrical hot electrode 4; secondly, the first hot electrode 7 and Put the sintered body into the second thermal electrode 4 to form a coaxial probe structure, as shown in Figure 3-②; at the same time, at the same time, the second thermal electrode compensation wire is attached to the second thermal electrode cylinder wall, and the high temperature inorganic glue is used to seal the first thermal electrode. Fix the positions of the first thermal electrode compensation wire and the second thermal electrode compensation wire and place them in a ventilated place to wait for curing, as shown in Figure 3-③;

S4, the surface of the temperature measuring end of the temperature measuring probe that has been cured is sanded in order from small to large, and then polished;

S5. Clean the end face of the temperature measuring probe that has been polished, and in the high vacuum coating machine, use magnetron sputtering to sputter the target onto the end face of the temperature measuring probe to form a NiCr film Coating layer 5, then on the surface of the NiCr film on this basis, coat SiO2 protective film 6 again, as shown in Figure 3-⑤;

S6. Select the customizable threaded tube 9 according to the customization requirements and put the temperature measuring probe into the customizable threaded tube, so that the two compensation leads 1, 1 and 11 are introduced into the lead sheath protective sleeve 10, and the temperature measurement is adjusted slightly After the length of the probe, fix it with flat-end slotted set screws 8, as shown in Figure 4.

In summary, it can be seen that nickel-chromium-nickel-silicon (NiCr/NiSi) alloy is a group of cheap metal thermocouple materials widely used, with strong oxidation resistance and corrosion resistance at high temperature, and good linearity of thermoelectric characteristics, High sensitivity and other characteristics; and coaxial thin film thermocouples require good insulation between the two thermal electrodes, between the compensation wires and between the hot junction film and the outside, and the response speed is related to the thickness of the hot junction film and coaxial Thermocouple sensors are required to be compact in structure, simple in preparation process, adaptable to installation in various occasions, and capable of serial production and customized processing.

The above is only a preferred embodiment of the present invention, but the scope of protection of the present invention is not limited thereto, any person familiar with the technical field within the technical scope disclosed in the present invention, according to the technical solution of the present invention Any equivalent replacement or change of the inventive concepts thereof shall fall within the protection scope of the present invention.

Claims (8)

1. a kind of customized transient response temperature sensor of size, which is characterized in that including：

Thermoprobe with coaxial probe structure, the coaxial probe structure have the first thermode, be formed with barrel with Second thermoelectricity of the radial direction around first thermode is surrounded and with first thermode by film composition hot junction The insulating layer of pole, filling first thermode and the second thermoelectricity clearance between poles；

One end of the coaxial probe structure is formed with the thin film coating as thermometric end；

First thermode and the second thermode that the other end of the coaxial probe structure is stretched out respectively by high temperature without Machine glue is connected with the second thermode compensating wire with the first thermode compensating wire and fixes to form changeover portion respectively；

The changeover portion partial insertion may customize in screwed pipe, and the customizable screwed pipe is machined with close to thermometric end one end outer wall External screw thread.

2. transient response temperature sensor according to claim 1, it is characterised in that：

The extremely Filamentous thermode of first thermoelectricity；The extremely cylindric thermode of second thermoelectricity.

3. transient response temperature sensor according to claim 1, it is characterised in that：

First thermode uses the NiSi alloy materials of identical mass percent with the first thermode compensating wire；Described Two thermodes use the NiCr alloy materials of identical mass percent with the second thermode compensating wire.

4. transient response temperature sensor according to claim 1, it is characterised in that：

The thin film coating by thermoprobe thermometric end coating surface hot junction film and protective film form.

5. transient response temperature sensor according to claim 1, it is characterised in that：

The insulating layer is made of insulating ceramics and high temperature inorganic glue.

6. transient response temperature sensor according to claim 5, it is characterised in that：

The material of the insulating ceramics is nano-ceramic powder, and high temperature inorganic glue is double bond DB5012 refractory inorganic adhesives.

7. transient response temperature sensor according to claim 1, it is characterised in that：

The customizable screwed pipe side is furnished with fluting flush end holding screw, for thermoprobe position to be fixed, and can According to the length that thermoprobe is adjusted in actual conditions certain amplitude.

8. a kind of method for preparing the customized transient response temperature sensor of above-mentioned size, including：

S1, the first thermode, the second thermode are subjected to surface clean；

S2, ceramic pressing furnace progress high temperature sintering, insulating ceramics system are put into after the first thermoelectricity pole surface coating nano ceramic is starched Coating sintering can be repeated several times to required thickness and shape in standby process；

S3, first to forming the progress bulk processing of sintered body surface after the processing of above-mentioned high temperature sintering and coating high temperature inorganic again Glue, while the filled high-temperature inorganic glue in the second thermode；Secondly the first thermode and sintered body are put into the second thermode To form coaxial probe structure；It is last simultaneously by the second thermode compensating wire be close to after the second thermode barrel using high temperature without Machine glue is placed ventilation after the position of the first thermode compensating wire and the second thermode compensating wire is fixed and is waited for admittedly Change；

S4, sanding and polishing processing is carried out to the surface of the thermometric end of the cured thermoprobe of completion；

S5, the end face of the thermoprobe of completion polishing treatment is cleaned, and in high vacuum coating unit, with magnetron sputtering side Formula deposits NiCr films and SiO2 protective films to form the thin film coating in thermoprobe end face successively；

S6, customizable screwed pipe is selected according to customized demand and thermoprobe is fitted into customizable screwed pipe so that two benefits It repays conducting wire and imported into conducting wire and cover in protective case absolutely, fixed after adjusting thermoprobe length with flush end fluting holding screw.