Novel multi-channel temperature measurement sheathed thermocouple

Abstract

The utility model discloses a novel multi-channel temperature measurement sheathed thermocouple, which comprises a pipe sleeve, a plurality of positive wires, a plurality of negative wires and an insulating filler, the pipe sleeve is made of the same material as the negative wires, the negative wires are electrically connected with the pipe sleeve, and the positive wires are arranged in the pipe sleeve. One end of each positive wire is electrically connected with the pipe sleeve at a plurality of different axial positions in the pipe sleeve, the positive wires share one negative wire, and the positive wires and the negative wires form a plurality of independent induced potentials at different positions of the pipe sleeve. According to the invention, temperature measurement is carried out at different positions of the pipe sleeve through the plurality of positive wires, and one negative wire can be shared, so that a plurality of independent induced potentials are formed, temperature measurement is carried out at the cold end, and the accuracy and sensitivity of temperature measurement can be improved; and a positive wire with a larger wire diameter can be selected in the pipe sleeve with the same size, so that the problem of burnout of the positive wire caused by large working temperature difference between different positions of the thermocouple is avoided.

Description

Technical Field

[0001] The utility model relates to the technical field of thermocouples, in particular to a novel multi-channel temperature measuring armored thermocouple. Background Art

[0002] Armored thermocouples are used as temperature measurement sensors to directly measure or control the temperature of fluids, steam and gaseous media and solid surfaces within the range of 0-1800℃ in various production processes. Armored thermocouples have many advantages such as flexibility, high pressure resistance, fast thermal response time and durability. Like industrial assembled thermocouples, they are used as temperature measurement sensors and are usually used in conjunction with display instruments, recording instruments and electronic regulators.

[0003] The basic principle of temperature measurement by armored thermocouple is thermoelectric effect. The two ends of two conductors of different components are welded to form a loop. The end directly measuring temperature is called hot end, also known as working end, and the terminal end is called cold end, also known as reference end. When there is a temperature difference between the working end and the reference end, a thermal current will be generated in the loop. When connected to a display instrument, the instrument will indicate the corresponding temperature value of the thermoelectric potential generated by the thermocouple. The thermoelectric potential of the armored thermocouple will increase as the temperature of the measuring end increases. The size of the thermoelectric potential is only related to the material of the thermocouple conductor and the temperature difference between the two ends, and has nothing to do with the length and diameter of the thermoelectrode.

[0004] When measuring the temperatures in different high-temperature areas, existing multi-point thermocouples mostly use a combination of armored thermocouples and outer sleeves. However, the assembly of armored thermocouples and outer sleeves is equivalent to reducing the sensitivity of temperature measurement. Moreover, because the wire diameters of existing armored thermocouples are of uniform size, the risk of resistance wire burning out is easily increased under high temperature differences. Summary of the invention

[0005] In view of this, the utility model aims to provide a novel multi-channel temperature measurement armored thermocouple which can avoid the burning of the resistance wire due to the large working temperature difference of the thermocouple.

[0006] In order to solve the above technical problems, the technical solution of the utility model is: a new type of multi-channel temperature measurement armored thermocouple, including a pipe sleeve, a positive wire and a negative wire for temperature measurement and an insulating filler filled in the pipe sleeve, the pipe sleeve is made of the same material as the negative wire, the negative wire is electrically connected to the pipe sleeve, a plurality of positive wires are provided, one end of the plurality of positive wires is electrically connected to the pipe sleeve at a plurality of different axial positions in the pipe sleeve, a plurality of positive wires share one negative wire, and the plurality of positive wires form a plurality of independent induced potentials with the negative wire at different positions of the pipe sleeve.

[0007] Preferably, the positive electrode wire is made of nickel-chromium alloy material.

[0008] Preferably, the negative electrode wire and the tube sleeve are made of nickel-silicon alloy material.

[0009] The technical effects of the utility model are mainly reflected in the following aspects: temperature is measured at different positions of the pipe sleeve by using multiple positive wires, and a negative wire can be shared to form multiple independent induced potentials, and temperature measurement is performed at the cold end, which can increase the accuracy and sensitivity of temperature measurement; multiple positive wires share the negative electrode, so that a positive wire with a larger wire diameter can be selected in a pipe sleeve of the same size, avoiding the problem of the positive wire burning out due to the large working temperature difference between different positions of the thermocouple, thereby extending the overall service life of the thermocouple. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] Figure 1 It is a schematic diagram of the overall structure of the utility model;

[0011] Figure 2 It is a partial structural schematic diagram of the utility model;

[0012] Figure 3 For this utility model Figure 2 A magnified schematic diagram of part A.

[0013] 1- pipe sleeve; 2- positive wire; 3- negative wire; 4- insulating filler; a- temperature measuring hot end; b- wiring cold end. DETAILED DESCRIPTION

[0014] The specific implementation modes of the present invention are further described below in conjunction with the accompanying drawings to make the technical solutions of the present invention easier to understand and grasp. Example

[0015] according to Figure 1-3 As shown, a novel multi-channel armored thermocouple for temperature measurement includes a tube sleeve 1, a positive wire 2 and a negative wire 3 for temperature measurement, and an insulating filler 4 filled in the tube sleeve 1. The positive wire 2 and the negative wire 3 are made of different conductor materials. One end of the positive wire 2 and the negative wire 3 for temperature measurement in the tube sleeve 1 is a temperature measurement hot end a, and the other end of the positive wire 2 and the negative wire 3 is a wiring cold end b. The temperature is measured at the wiring cold end b through the induced potential formed between the temperature measurement hot end a and the wiring cold end b. Generally, the wire diameter of the positive wire 2 and the negative wire 3 is unchanged when measuring temperature zones of different temperatures. When the measured temperature is high and the temperature difference between different high temperature zones is large, there may be a danger that the high temperature will easily burn the wire due to the small wire diameter, shortening the service life of the thermocouple.

[0016] In the present application, the sleeve 1 is made of the same material as the negative electrode wire 3, the negative electrode wire 3 is electrically connected (welded) to the sleeve 1, so that the sleeve 1 serves as a common negative electrode, and the negative electrode wire 3 and the sleeve 1 are made of nickel silicon alloy (NN) material; the positive electrode wire 2 is provided with multiple positive electrode wires, and the positive electrode wire 2 is made of nickel chromium alloy (NP) material. One end of the multiple positive electrode wires 2 is electrically connected (welded) to the sleeve 1 at multiple different axial positions in the sleeve 1, and the multiple positive electrode wires 2 share the sleeve 1 as the negative electrode, that is, the multiple positive electrode wires 2 share one negative electrode wire 3, and the multiple positive electrode wires 2 form multiple independent induced potentials with the negative electrode wire 3 at different positions of the sleeve 1, so as to achieve the effect of measuring the temperature at the cold end b of the wiring.

[0017] Furthermore, since the plurality of positive wires 2 share one negative wire 3, the negative wire 3 occupies less space, so that the positive wire 2 with a larger wire diameter can be selected in the pipe sleeve 1 of the same size, thereby avoiding the problem of the positive wire burning out due to the large working temperature difference between different positions of the thermocouple, thereby extending the service life of the thermocouple as a whole.

[0018] For example, taking the N-type thermocouple as an example, the N-type thermocouple has the advantages of good linearity, large thermoelectric potential, high sensitivity, good stability and uniformity, strong antioxidant performance, low price, and is not affected by short-range ordering. It can measure high temperatures and a wide range. According to the usage, 6 temperature-measurable hot ends a can be built in, namely a1, a2, a3, a4, a5, and a6. Each point a is welded by a positive wire 2 and a sleeve 1, and the other end of the positive wire 2 is connected to the wiring cold end b for temperature measurement. At the same time, the negative wire 3 is welded in the sleeve 1, so that the sleeve 1 becomes a common negative electrode. The temperature-measuring hot ends a of a1-a6 are respectively welded with the sleeve 1 welded with the negative wire 3 to form 6 independent induced potentials, so as to achieve the effect of temperature measurement at the cold end.

Claims

1. A novel multi-channel temperature measurement armored thermocouple, comprising a tube sleeve, a positive electrode wire and a negative electrode wire for temperature measurement and an insulating filler filled in the tube sleeve, characterized in that: The sleeve is made of the same material as the negative electrode wire, the negative electrode wire is electrically connected to the sleeve, a plurality of positive electrode wires are provided, one end of the plurality of positive electrode wires is electrically connected to the sleeve at a plurality of different axial positions in the sleeve, the plurality of positive electrode wires share one negative electrode wire, and the plurality of positive electrode wires form a plurality of independent induced potentials with the negative electrode wire at different positions of the sleeve.

2. A novel multi-channel temperature measurement armored thermocouple according to claim 1, characterized in that: The positive electrode wire is made of nickel-chromium alloy material.

3. A novel multi-channel temperature measurement armored thermocouple according to claim 1, characterized in that: The negative electrode wire and the tube sleeve are made of nickel-silicon alloy material.

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