JPH03185320A - Temperature sensor - Google Patents

Abstract

PURPOSE:To prevent a bending crack and a similar damage of a protecting tube of a temperature sensor even when it is employed in a place where the temperature is high and varies in a short time and where strong mechanical shock is exerted, by putting a sensing element in an MI cable with a cushion material of inorganic fibers interposed. CONSTITUTION:Inorganic insulative powder 2 of MgO or the like located at the fore end part of an MI cable 3 having a construction wherein a conductor 11 is held in a sheath 1 of Hastelloy X or the like with the inorganic insulative powder 2 interposed and is tightened, is removed by expanding the base end side of a round-rod-shaped hole in which a sensing element 6 is to be put. A space 4 formed by removing the inorganic insulative powder 2 is made deeper than the sensing element 6, and the sensing element 6 is fitted and held firmly in this space 4 with a cushion material 5 of inorganic fibers such as alumina fibers interposed. Even when the sheath 1 is bent, for instance, when a temperature sensor thus constructed is employed in a place wherein a temperature in high, heat cycle is intense and strong mechanical shock are given, the temperature sensor is prevented from cracking, since the cushion material 5 is interposed.

Description

DETAILED DESCRIPTION OF THE INVENTION "Industrial Application Field" The present invention relates to a temperature sensor, and particularly to a temperature sensor used at a single location that is subject to high temperatures, severe thermal cycles, and large mechanical shocks.

"Problems to be solved by the prior art and the invention" For example, a temperature sensor for a rocket burner has a
The temperature reaches a high temperature of around 0℃, and the combustion cut-off is 800℃.
If the temperature sensor is used in a location where the temperature changes from -1200°C in a short period of time and is subject to severe mechanical shock, the temperature sensor's protection tube may bend and the temperature sensor may crack, making it impossible to provide a reliable product. There wasn't.

"Means and Effects for Solving the Problem" In view of the above circumstances, the present invention provides a sensing technology that enables the temperature sensor to be used at high temperatures, where thermal cycles fluctuate rapidly and where mechanical shocks are severe. The element is housed within the Ml cable with an inorganic fiber cushioning material interposed therebetween.

Embodiments The present invention will be described in detail below with reference to FIGS. 1 to 5 of the accompanying drawings.

M made by interposing an inorganic insulating powder 2 such as MgO in a sheath l such as Hastelloy X, housing the core wire 11, and squeezing it.
l Remove the inorganic insulating powder 2 at the tip of the cable 3 by expanding the proximal end with a round bar-shaped hole into which the sensing element 6 described below will be inserted. The void 4 formed by removing the inorganic insulating powder 2 is shaped deeper than the sensing element 6, and the sensing element 6 is snugly fitted into the void 4 by interposing an inorganic fiber cushioning material 5 such as alumina fiber. and accommodate it.

Here, the cushioning material 5 is also filled into the cushioning material insertion hole 7 which is opened at the inner part of the cavity 4 and the inner end of the cavity 4 of the sensing element 6. Also fill the tip side.

Note that the cushioning material 5 must not be one that would become hot and generate gas to contaminate the sensing element 6.

In addition, as shown in FIGS. 3 to 5, the sensing element 6 is constructed by winding a resistance wire 13 around the outer peripheral surface of the alumina winding frame 12, and connecting the resistance wire 13 to the enamel-coated 14L and connecting it to the step frame lead wire 19. However, as shown in FIG. 5, the resistance wire 13 may be wound directly around the outer periphery of the alumina winding frame 12, or the alumina winding frame 12 may be coated with enamel and the resistance wire may be wound on top of it. , may be coated with enamel. M the stile lead wire 19! The tip of the core wire 11 accommodated in the cable 3 is laser welded 14L, the tip of this Ml cable 3 is sealed with a tip sealing fitting 15 such as Hastelloy X, and fixed by TIG welding 16.

The proximal end of this Ml cable 3 is accommodated in a mounting screw 17 made of Hastelloy X or the like, and fixed by Au-Ni-Pd brazing 18. Further, the outlet pipe 20 is attached to the base end side of the screw 17 by TIG welding 21.

"Effects of the Invention" As described above, the present invention removes the inorganic insulating powder at the tip of the Ml cable, which is formed by interposing inorganic insulating powder in the sheath, accommodating the core wire, and squeezing it. Since this is a temperature sensor in which a sensing element is housed in a space created by removing an inorganic fiber cushioning material, the thermal cycle is 800°C to - at a high temperature of about 800°C.
When used in places where temperature changes up to 200℃ in a short period of time and where there is severe mechanical shock, even if the temperature sensor sheath bends, there is a cushioning material in place, so the temperature sensor will not crack and be reliable. It is possible to use a certain temperature sensor.

Furthermore, since the cushioning material used is a material that does not contaminate the sensing element even at high temperatures, it does not impair the reliability of the temperature sensor.

[Brief explanation of drawings]

Fig. 1 is a vertical cross-sectional view of a specific embodiment of the present invention, Fig. 2 is a longitudinal cross-sectional view of the main part of the temperature sensor, Fig. 3 is a front view of the sensing element, and Fig. 4 is the right side of Fig. 3. 5 is an enlarged longitudinal sectional view of the V section in FIG. 3. l... Sheath 2... Inorganic insulating powder 11... Core wire 3... Ml cable 4... Vacant space 6... Sensing element 5... Cushion material supplier Okazaki Co., Ltd. Manufacturer

Claims (1)

[Claims] (1) Remove the inorganic insulating powder at the tip of the MI cable by inserting inorganic insulating powder in the sheath, accommodating the core wire, and squeezing it. A temperature sensor in which a sensing element is housed with a high-quality cushioning material interposed therebetween.