JPS6145463Y2 - - Google Patents

Description

[Detailed description of the invention] The present invention relates to a temperature sensor for measuring temperature distribution in a specific direction of a temperature-measuring object, and more specifically to a temperature sensing part of a plurality of sheathed thermocouples or a sheathed resistance thermometer. The present invention relates to a multi-point temperature sensor in which the temperature sensors are arranged at different positions in the length direction and housed in a protection tube.

Accurately and quickly detecting the temperature distribution in a specific direction of the object to be measured, such as the wall of various industrial furnaces or the reaction tower in the petrochemical industry, is an important measurement from the standpoint of safe operation of the furnace and quality control of the product. It has become an element. For this reason, multi-point temperature sensors that measure the temperature distribution in a specific direction of a body to be measured have been proposed. After joining a metal wire of the same outer diameter to the tip of each temperature-sensing part of a sheathed thermocouple or sheathed resistance thermometer, and storing each temperature-sensing part in a protective tube with the parts facing each other, This is a structure in which the diameter of the protective tube is reduced and molded into one piece. However, with this configuration, the mechanical strength of the sheath of the sheathed thermocouple or sheathed resistance thermometer and the metal wire bonded to the tip of the temperature sensing section is different, so when reducing the diameter of the protection tube, the overall length must be reduced. It is not possible to reduce the diameter uniformly over the entire length of the protective tube, resulting in a void inside the protective tube, and the residual air in this void not only reduces the responsiveness and accuracy of temperature measurement due to heat insulation and convection. Because the temperature-sensing parts are arranged irregularly in the protection tube, the heat reception condition from the circumference of the protection tube differs, resulting in a reduction in measurement accuracy.Furthermore, the length of each sheath and metal wire By changing the temperature sensing parts, the mechanical strength of each sheath and metal wire differs. Therefore, when reducing the diameter of a thermocouple or The drawback remains that the resistance temperature detector is easily damaged by the pressure of diameter reduction.

This proposal was devised to eliminate the above-mentioned drawbacks, and its gist is that it can quickly reach thermal equilibrium with the object to be measured, and that it is made of the same material as the sheath in order to prevent the thermal equilibrium from being disturbed. The metal core material is integrated with a temperature sensing element consisting of a sheathed thermocouple or a sheathed resistance temperature sensor and a protection tube to prevent the creation of voids in the protection tube and to detect temperature. The objective is to construct a multi-point temperature sensor with a unified arrangement of parts.

If you explain in detail in the attached drawing below, the drawing shows the temperature measuring element 4.
An example using a sheathed thermocouple in which thermocouple wires 1 and 1a are housed in a sheath 3 via an insulating material 2 is shown, and the metal core 5 holding the temperature measuring element 4 is connected to the sheath 3. It is made of the same material, preferably a metal with good thermal conductivity such as copper, and a plurality of long grooves 6 are formed in the axial direction of the outer periphery (i.e., the length direction of the core material 5) from the tip (left end in Fig. 3). The long grooves 6 are formed with different distances from each other, and the long grooves 6 have a predetermined space even when the temperature measuring element 4 is fitted therein. By fitting the temperature sensing element 4 into each of the long grooves 6 with the temperature sensing portion 7 in contact with or close to the step at the tip of the long groove, each temperature sensing element 4 is fitted. The temperature-sensing parts 7 are arranged with their positions shifted from each other in the length direction of the metal core material, and the metal core material 5 and the temperature-sensing element 4 are made of the same material as the sheath 3 and preferably made of a good material such as copper. Each temperature sensing element 4 is deformed and buried in the long groove 6 by fitting and inserting it into a metal protection tube 8 made of a thermal conductor and reducing the diameter of this metal protection tube 8 using a swaging machine or the like. The end of the protective tube is joined to the outer circumferential surface of the end of the core material to form an integral body with no voids as shown in FIG.

In the multi-point temperature sensor of the present invention as described above, each temperature sensing element 4 is positioned in the long groove 6 formed on the outer periphery of the metal core material 5, with its temperature sensing part 7 being positioned in the length direction of the metal core material. The metal core material 5 is constructed by fitting each temperature sensor 4 in a staggered arrangement and embedding it in each long groove 6 by reducing the diameter of the externally fitted metal protection tube 8. The temperature measuring element 4... and the metal protection tube 8 are integrally joined and have no internal voids, making it look like a single rod, which eliminates the harmful effects of residual air in the voids and enables temperature measurement. In addition to preventing a decrease in responsiveness and accuracy, each temperature sensing element 4 is fitted and held in its own long groove 6, so it is regularly arranged, so there is no risk of damage, and the metal The heat receiving condition from the outer periphery of the protection tube is also the same as that of each temperature measuring element, so there is no risk of reducing measurement accuracy. Furthermore, since the metal core material 5 and the metal protection tube 8 are made of the same material as the sheath 3 of the temperature measuring body 4..., thermal equilibrium is quickly reached with the body to be measured when temperature is measured, and the temperature can be measured without disturbing the thermal equilibrium. This makes it possible to improve measurement accuracy, and if a metal with good thermal conductivity such as copper is used for the metal core 5, metal protection tube 8, and sheath 3, the responsiveness of temperature measurement can be accelerated.

[Brief explanation of the drawing]

FIG. 1 is a longitudinal sectional side view showing one embodiment of the present invention before diameter reduction processing, FIG. 2 is a longitudinal sectional side view after diameter reduction processing, and FIG. 3 is a XX sectional view in FIG. 2. 1...Thermocouple wire, 2...Insulating material, 3...Sheath, 4...
Temperature measuring body, 5... Metal core material, 6... Long groove, 7... Temperature measuring part,
8...Metal protection tube.

Claims (1)

[Scope of utility model registration request] A plurality of temperature sensing elements such as sheathed thermocouples or sheathed resistance thermometers are fitted into a plurality of long grooves formed in the length direction on the outer periphery of a metal core material, and the temperature sensing portion of each measuring element is are arranged with their positions shifted in the length direction of the core material, and the diameter of the metal protection tube that fits around the metal core material and the temperature sensing element is reduced in diameter, each temperature sensing element is buried in the long groove, and the end of the protection tube is A multi-point temperature sensor made by joining the outer edge of a metal core to the outer periphery of the edge.