JPS5812311Y2 - thermocouple sensing wire - Google Patents

Description

[Detailed description of the invention] As shown in Figure 1, the thermocouple sensing wires used in conventional thermocouple differential fire detectors are composed of two types of pipe-shaped thermocouple wires a and a made of different materials. ' are connected alternately, and the inner periphery of the connection part between each P end of one thermocouple wire a and the other Q thermocouple wire a' connected to the two ends. A rod-shaped heat storage material is inserted into the heat storage material, and the heat capacity of the connection part on one end side of each of the wires a for one thermocouple is increased by the heat storage material, and the heat storage material is used as a cold junction part. The heat capacity of the connection part on the other end side of each of the service lines a is reduced to serve as a hot junction part.

However, when the heat capacity of the cold junction is increased by lengthening the rod-shaped heat storage material and increasing the capacity of the heat storage material, the entire needle circumference of the rod-shaped heat storage material becomes larger than the thermocouple wires a and a'.
Since the hot junction is in contact with the inner circumference of the heat storage material, the heat of the temperature contact is transferred to the heat storage material, and therefore the thermocouple sensing wire is connected to the heat storage material at a certain rate. When the thermocouple sensing wire is installed in an ambient atmosphere where the temperature rises, the temperature difference between the cold junction and the hot junction is unlikely to become large. When the heat capacity becomes small and the thermocouple sensing wire is placed in an atmosphere where the temperature rises at a constant rate, the temperature of the cold junction increases almost as much as the hot junction, and the temperature between the cold and hot junctions increases. The disadvantage was that the temperature difference was difficult to increase and the sensitivity of the thermocouple sensing wire was poor.

The present invention is intended to eliminate the above-mentioned drawbacks of the conventional technology, and an embodiment of the present invention will be described below with reference to FIG. 2.1.
Reference numeral 1' denotes two types of thermocouple wires made of different materials, which are formed into a cylindrical body or a cylindrical body having an opening on the negative side.

Thus, each plurality of thermocouple wires 1° 1' are connected alternately to each other.

Reference numeral 2 denotes a rod-shaped heat storage material, which is made of brass, iron, or other material with good heat conduction.The rod-shaped heat storage material 2 has an enlarged outer diameter portion 2a formed on a part of its outer peripheral body.

The rod-shaped heat storage material 2 is inserted into the inner peripheral body of the thermocouple wires 1 and 1', and connects one end of one thermocouple wire 1 to the other thermocouple wire 1 connected to each end. The outer circumferential shell of the enlarged outer diameter section 2a is brought into contact with the inner circumferential shell of the connection part of , and there is a gap between the outer circumferential shell of the heat storage material 2 other than the enlarged outer diameter section 2a and the inner circumferential shell of the thermocouple wire 1.1'. A gap 3 is formed.

FIG. 3 shows a different embodiment of the present invention, in which the heat storage materials 2 in FIG. 2 are integrally connected.

The present invention has the above-mentioned configuration, and the enlarged outer diameter portion 2a of the heat storage material 2
The connection part of the thermocouple wires 1, 1' that is in contact with the heat storage material 2 becomes a cold junction, and the connection part of the thermocouple wire 1, 1' that is not in contact with the heat storage material 2 becomes a hot junction, and the ambient temperature When the temperature rises at a rate higher than a predetermined rate, the heat capacity of the cold junction is large because the cold junction is in contact with the heat storage material, so the temperature of the cold junction does not follow the rise in ambient temperature and is small, causing the heat capacity of the hot junction to decrease. Since the hot junction part is not in contact with the heat storage material and is small, the hot junction part increases as the ambient temperature rises, and voltage is generated at both ends of the sensing wire, causing the ambient temperature to exceed a predetermined rate. It is possible to detect an increase in the

1. When assembling the sensing wire according to the present invention, 1. For example, as shown in FIG. It is assembled by.

As described above, the present invention has an enlarged outer diameter portion of the rod-shaped heat storage material 2 on the inner peripheral body of the connection portion between each one end of one thermocouple wire 1 and the other thermocouple wire 1' connected to the one end. Since a gap 3 is formed between the outer circumferential shell of the rod-shaped heat storage material 2 other than the enlarged outer diameter portion 2a and the inner circumferential shell of the thermocouple wires 1 and 1' by abutting the outer circumferential shell of the heat storage material 2a, the capacity of the heat storage material can be reduced. By increasing the size, the heat capacity of the cold junction part can be increased, and at the same time, the heat of the hot junction part is difficult to conduct to the heat storage material, which has the effect of providing a highly sensitive thermocouple sensing wire.

[Brief explanation of drawings]

FIG. 1 is a cross-sectional view of a conventional thermocouple sensing wire, FIGS. 2 and 3 are cross-sectional views of different embodiments of the present invention, and FIG. 4 is an explanatory diagram of the assembly of the sensing wire of the present invention. 1.1' is a thermocouple wire, 2 is a heat storage material, 2a is an enlarged outer diameter portion, and 3 is a gap.

Claims (1)

[Scope of utility model registration request] A plurality of thermocouple wires made of different materials formed in a cylindrical body or a cylindrical body having an opening on the negative side are connected alternately to each other, and some of the outer circumferential shells have an enlarged outer diameter. A rod-shaped heat storage material that forms a section is inserted into the thermocouple wire, and the inside of the joint between one end of one thermocouple wire and the other thermocouple wire connected to each end is inserted into the thermocouple wire. A thermoelectric device characterized in that the outer circumferential shell of the enlarged outer diameter portion is brought into contact with the circumferential shell, and a gap is formed between the outer circumferential shell of the heat storage material other than the enlarged outer diameter portion and the inner circumferential shell of the thermocouple wire. Pair sensing wire.