JPH0321462Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Technical Field of the Invention] The present invention relates to a connection structure for connecting a thermocouple and a compensation conducting wire.

[Technical background of the invention and its problems]

When a thermocouple, for example a sheath type thermocouple, is used, the thermocouple is connected to a compensating conductor, and the compensating conductor is connected to a meter.

The thermocouple and the compensating lead wire are two core wires led out from the end of the thermocouple's protective tube (the sheath in the case of a sheathed thermocouple), and two core wires lead out from the end of the covering insulator of the compensating lead wire. The lead wire of the book is connected by soldering or brazing, and this connection is molded with resin. By the way, when such a thermocouple is used, there is an inconvenience that the lead wire often breaks, and there has been a demand for improved reliability. In this case, soldering is easier to break than brazing, and further improvements have been sought.

[Purpose of invention]

This invention was made based on the above circumstances,
The purpose of the present invention is to provide a connection structure between a thermocouple and a compensating conductor that prevents disconnection accidents and improves reliability.

[Summary of the idea]

As a result of experimental research regarding the above-mentioned disconnection, the inventors of the present application found that the cause of this is mainly due to the direction in which the two lead wires 6 are in parallel contact with each other when the compensation conductor is bent (in the direction of arrow 12 in FIG. 1). When bent, the bending radius is large, so the thinness of the thermocouple core wire (0.05 to 0.53
mm), it was found that wire breakage is likely to occur. The invention of the present application was made based on this knowledge.

That is, in the connection structure between a thermocouple and a compensating lead wire according to the present invention, the core wire led out from the protective tube of the thermocouple is connected to a coil spring for the purpose of alleviating the force exerted by the movement of the lead wire led out from the covering insulator of the compensating lead wire. or the core wire and the lead wire are loosely connected with a length larger than the required connection dimension, and the connection portion is formed so that play in the core wire is effectively used. The device is characterized in that it is surrounded by a viscous insulating material for the purpose of fixing and maintaining insulation, and that this insulating material is molded with a resin for the purpose of fixing and maintaining insulation.

[Example of idea]

Embodiments of the present invention will be described below with reference to drawings.

FIG. 1 shows an embodiment in which the present invention is applied to a connection structure between a sheathed thermocouple and a compensation conductor.

In the figure, 1 is a sheathed thermocouple, and 2 is a compensating conductor wire with an oval cross section. Two core wires 4, 4 led out from the base end of the sheath 3 in the thermocouple 1 are each formed in the shape of a coiled spring. The ends of the core wires 4, 4 of the thermocouple 1 are connected and fixed to two lead wires 6, 6 led out from the ends of the covering insulator 5 of the compensating conductor 2 by soldering. 7 in the figure is the core wire 4,
4 and the lead wires 6, 6 are soldered together. The coiled core wires 4, 4 of the thermocouple 1 and the soldered portions 7 between the core wires 4, 4 and the lead wires 6, 6 of the compensating conductor 2 are surrounded by an insulating material 8, such as silicone rubber, which is viscous at room temperature. is embedded inside it. The molding for embedding the core wires 4, 4 and lead wires 6, 6 with the insulating material 8 can be easily performed manually at room temperature. The sleeve 9 fixed to the end of the thermocouple 1 is filled with synthetic resin 10, and the synthetic resin 10 is cured to form the sheath 3 end of the thermocouple 1, the covered insulator 5 end of the compensating conductor 2, and An insulating material 9 surrounding the connecting portions between the core wires 4, 4 and the lead wires 6, 6 is integrally molded. Note that a support 11 is attached to the sheath 3 of the thermocouple 1, and the covering insulator 5 of the compensation conductor 2 is supported by this support 12. Further, lead wires 6, 6 are led out from the other end of the compensation conducting wire 2 and connected to a meter (not shown).

In this connection structure between the thermocouple 1 and the compensating lead wire 2, the core wires 4, 4 of the thermocouple 1 are formed into a coil spring shape and have elasticity, so that the lead wires 6, 6 of the compensating lead wire 2 are When the core wires 4, 4 and the lead wires 6, 6 are moved and a tensile or compressive force is applied to the connection portion between them, the coiled core wires 4, 4 expand and contract, and the spring action causes the connection portion to Absorbs and relieves applied tensile or compressive forces. In other words, the connecting portion between the core wires 4, 4 and the lead wires 6, 6 has a buffering effect that relieves the force acting on this connecting portion. In addition, the viscous insulating material 8 surrounding the connecting portions between the core wires 4, 4 and the lead wires 6, 6 allows the core wires 4, 4 and the leads 6, 6 to move while allowing the core wires 4, 4 to move as a coil spring (expanding/contracting motion). It has the role of insulating and protecting the wires 6, 6.

Therefore, if the end of the compensation conductor 2 connected to the thermocouple 1 is bent as shown in the illustrated virtual line in order to connect the compensation conductor 2 to the meter, the compensation conductor 2 will be located on the outer periphery of the bent portion. One of the lead wires 6 moves to be drawn into the coated insulator 5. In this case, a tensile force is applied to the connection between the moving lead wire 6 and the core wire 4 of the thermocouple 1, but the core wire 4, which has a coil spring shape, stretches and absorbs the tensile force. Therefore, a disconnection accident at the connection between the core wire 4 and the lead wire 6,
In particular, breakage of the core wire 4 can be prevented.

FIG. 2 shows another embodiment of the present invention, in which the same parts as in FIG. 1 are given the same reference numerals. In this embodiment, the core wires 4, 4 of the thermocouple 1 and the compensation conductors 6, 6
The core wires 4, 4 and the lead wires 6,
6 are connected in a relaxed state. In this case, for example, even if the lead wire 6 moves and is drawn into the inside of the coated insulator 5, the amount of movement of the lead wire 6 is reduced by the amount of movement of the lead wire 6 and the core wire 4 at the connection part.
Since the tension is absorbed by the length of , no tensile force is applied to the connection between the core wires 4, 4 and the lead wires 6, 6, thereby preventing the occurrence of wire breakage accidents.

Note that the connection structure of the present invention is not limited to the embodiments described above, and can be implemented with various modifications without changing the gist.

[Effect of idea]

As explained above, according to the present invention, the force acting on the connection between the core wire of the thermocouple and the lead wire of the compensating conductor can be absorbed by the buffering effect of the connection itself, thereby preventing disconnection accidents at the connection. A highly reliable connection structure between a thermocouple and a compensating conductor can be obtained.

[Brief explanation of drawings]

FIGS. 1 and 2 are cross-sectional views showing different embodiments of the present invention. DESCRIPTION OF SYMBOLS 1... Thermocouple, 2... Compensation conductor, 3... Sheath, 4... Core wire, 5... Covered insulator, 6... Lead wire, 7... Soldering part, 8... Insulating material, 9...
...Synthetic resin.

Claims (1)

[Scope of utility model registration request] In a structure in which a core wire led out from a protective tube of a thermocouple and a lead wire led out from a covered insulator of a compensating conductor wire are connected, the core wire is formed into a coil spring shape and connected to the lead wire, or the core wire A thermocouple formed by connecting the lead wire loosely with a length larger than the required connection dimension, surrounding this connection part with a viscous insulating material, and molding the insulating material with a synthetic resin. and the connection structure with the compensation conductor.