JPH0140026Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a temperature sensor with improved thermal response.

An example of a conventional temperature sensor is one having a structure shown in FIG.

In FIG. 1, 1 is a bottomed metal pipe such as stainless steel, 2 is a heat-sensitive element such as a thermistor or thermocouple, which is placed in contact with or close to the bottom of the pipe 1, and the lead wire 2a is a metal pipe with a bottom, such as stainless steel.
It is derived from Reference numeral 3 denotes an insulating material filled in the pipe 1, which fixes the heat-sensitive element 2 within the pipe 1 and maintains insulation between the lead wires 2a.

By the way, in such a temperature sensor, when the bottom of the pipe 1 is brought into contact with the object to be measured, since the entire pipe 1 is made of metal and the inside is filled with an insulating material 3, In addition, the heat-sensitive element 2 is fixed with an insulating material 3 so as to be located at the bottom of the long pipe 1, and the leader wire 2a is separated and fixed so as not to be short-circuited. However, it was difficult to produce a uniform product in terms of workability, and there were problems in terms of yield. The smaller the diameter of the pipe 1 is made in order to improve the thermal response, the more the above-mentioned problems will occur.

This invention aims to rectify the shortcomings mentioned above.
The purpose of this is that the contact area of the heat-sensitive part to the temperature-measuring object is large, allowing for stable temperature measurement, and the heat capacity is small, which improves thermal response.In addition, the leader line of the heat-sensitive element is completely separated. The object of the present invention is to provide a temperature sensor that can be placed anywhere and is free from the risk of short circuits.

An embodiment of the present invention will be described below with reference to FIG.

In the figure, reference numeral 4 denotes a cylindrical ceramic insulator having at least two through holes 4a formed in its axial direction and a concentric recess 4b formed in one end surface. In addition, the said through-hole 4a is opened to the said recessed part 4b. Reference numeral 5 denotes a heat-sensitive element such as a thermistor or thermocouple, which is housed in the recess 4b of the insulator 4, and a lead wire 5a is led out to the outside through the through hole 4a. Reference numeral 6 denotes a bottomed cap made of metal with good thermal conductivity, and is fitted into the recess 4b of the insulator 4.

The heat-sensitive element 5 is preferably brought into contact with the bottom of the cap 6, and if the heat-sensitive element 5 is a thermocouple, it is fixed by brazing or the like.

Further, the cap 6 may be fixed to the insulator 4 using an adhesive 7 if necessary. In this case, the adhesive 7 may be resin-based or
It is best to use inorganic materials.

Furthermore, it is preferable to attach the cap 6 so that the bottom surface of the cap 6 and the end surface of the insulator 4 are substantially flush with each other. This means that when the temperature sensor is brought into contact with the surface of the temperature-measuring object, not only the cap 6 but also the end face of the insulator 4 will come into contact with the temperature-measuring object, and the contact area will become large, making it difficult to accurately measure temperature. Temperature detector becomes possible.

A metal pipe 8 is fitted and fixed to the outer periphery of the insulator 4 to prevent the insulator 4 from being mechanically destroyed by impact.

Therefore, the temperature sensor according to the present invention is arranged on the outlet side (lower side in FIG. 2) of the leader line 5a of the heat-sensitive element 5.
The cap 6 is pressed by a spring force such as a spring to bring the cap 6 into contact with the object to be measured with a constant pressure, and as a result, the cap 6 receives heat from the object to be measured. A heat-sensitive element 5 placed in contact with or near the body detects the temperature of the object to be measured, and outputs the detected temperature to the circuit via a leader line 5a. Here, since the heat receiving part is only the cap 6, the heat capacity is small, and therefore the thermal response is good.
In addition, since the contact area with the object to be measured can be increased, accurate temperature detection is possible.
Since it is inserted through the through hole 4a of the insulator 4 and led out, there is no risk of a short circuit.

In addition, in the above embodiment, an insulator 4 having a through hole 4a and a recess 4b communicating therewith is shown, but as another example,
Of course, it may be formed from a first insulator having a through hole and a second insulator fitted around the outer periphery of this insulator and having a recess formed on one end surface. That's true.

As described above, the present invention includes forming at least two through holes in an insulator, forming a recess communicating with the through holes, housing the heat-sensitive element in the recess, and leading out the lead wire through the through hole. In addition, by fitting a cap with good heat conduction into the recess and bringing this cap into contact with the temperature-measuring object, the contact area of the heat-sensitive section with the temperature-measuring object is increased, making it stable and In addition to being able to measure temperature accurately, the heat-sensitive part has a small heat capacity and improves thermal response.
Since the lead wires are completely separated by the through holes in the insulator, there is no possibility of short circuits.

[Brief explanation of the drawing]

FIG. 1 is a sectional view showing an example of a conventional temperature sensor, and FIG. 2 is a sectional view showing an embodiment of the temperature sensor according to the present invention. 4...Insulator, 4a...Through hole, 4b...Recess, 5...Heat-sensitive element, 5a...Leader wire, 6...Cap.

Claims (1)

[Scope of utility model registration request] an insulator having at least two through holes in the axial direction and a recess in the center of one end surface; a heat-sensitive element housed in the recess of the insulator and having a lead wire inserted into the through hole; A temperature sensor consisting of a bottomed cap made of thermally conductive material that is fitted and fixed into a recess in an insulator.