JPH035071Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a temperature switch comprising a reed switch, an annular permanent magnet, and an annular temperature-sensitive magnetic material, and particularly to a temperature switch suitable for detecting liquid temperature.

When a temperature switch element consisting of a reed switch, an annular permanent magnet, and an annular temperature-sensitive magnetic material is used to detect liquid temperature, it is conventionally housed in a metal case with a threaded part on the outer periphery as shown in Figure 1, and the case itself is A configuration in which one terminal is used is adopted.

In FIG. 1, a temperature switch element 1 is a reed switch 2 with an annular permanent magnet 3 and an annular temperature-sensitive magnetic material 4 fitted together on the outer periphery, and a case 5 is a bottomed cylindrical body made of brass or the like. , 6 is filled resin, 7
8 is an O-ring, 8 is an insulating lid, 9 is an external connection terminal, 10 is an annular metal plate, and 11 is an adhesive. Lead 2a on the bottom side of case 5 of reed switch 2
is connected to the bottom of the case 5 by soldering, brazing, etc., and the other lead 2b passes through an insulating lid 8 fixed by caulking the opening periphery of the case 5 along the metal plate 10 to connect to an external connection terminal. The temperature switch element 1 is airtightly housed and fixed in the case 5 by applying an adhesive 11 on the lid body 8.

In this structure, the leads 2a and 2b are each provided with bent parts, but the reed switch 2 is connected to the case 5.
Since the reed switch 2 is fixed at the top and bottom, the stress applied to the tubular body of the reed switch 2 due to expansion and contraction of the case and leads during thermal cycling is not sufficiently alleviated, resulting in poor reliability.

In addition, when detecting different liquid temperatures for the liquid in one container, it is sufficient to install two temperature switches with different operating temperatures as shown in Figure 1. Two screws are provided at two locations, requiring two installation man-hours.

The present invention was developed in view of the above-mentioned situation, and aims to provide a temperature switch that can detect at least two levels of liquid temperature, withstands severe thermal cycles, and requires less man-hours for installation on the detected part. purpose.

According to the present invention, an annular permanent magnet and an annular temperature-sensitive magnetic material are fitted and arranged on the outer periphery of the reed switch, and the temperature switch element has a first operating temperature. The annular permanent magnet and the annular temperature-sensitive magnetic body are fitted and arranged in the first part.
and a second temperature switch having a second operating temperature different from the operating temperature of the reed switch are housed side by side in a bottomed cylindrical non-magnetic case with their axial ends aligned with each other, and one lead of the reed switch is connected to the reed switch. A composite temperature switch is obtained in which the lead wires are connected as bridges, the lead wires are connected to the case, and the other leads of the reed switch are individually connected to external connection terminals by passing through an insulating cover plate. It will be done.

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

FIG. 2 is a sectional view of an embodiment of the present invention. Referring to the figure, temperature switch elements 1 and 1', which are composed of a reed switch 2, an annular permanent magnet 3, and an annular temperature-sensitive magnetic body 4 and have different operating temperatures (for example, 90°C and 105°C), are connected to an annular permanent magnet. The magnets 3 and 3' are placed adjacent to each other with their axial end surfaces aligned, and the lengths of the leads 2a and 2'a of the reed switches 2 and 2' are short enough that the heat generated during spot welding does not affect the pipe body. One end of a soft lead wire 12 (for example, an electric tin-plated extremely mild steel wire) is connected to the leads 2a, 2'a by spot welding, and the other end is connected to the leads 2a, 2'a. Shape it so that it faces in the direction of extension. The temperature switch elements 1, 1' thus assembled are housed in a bottomed cylindrical case 5 made of brass or the like, and the lead wire 12 is connected to the bottom of the case 5 by soldering. The temperature switch elements 1, 1' are fixed by filling the case 5 with a resin 6 having elasticity and good thermal conductivity, such as silicone resin. The leads 2b and 2'b of the reed switches 2 and 2' are passed through the insulating lid 8 independently, and the opening of the case 5 is covered with the lid 8 via the O-ring 7. Board 10
is placed, and the opening periphery of the case 5 is caulked along the shoulder of the metal plate 10 to fix the lid body 8. Lead 2b,
2'b is connected to the external connection terminals 9, 9' by soldering, and adhesive 11 is applied onto the lid 8.

As described above, since the device of the present invention has a structure in which two temperature switch elements are housed in one case, the number of man-hours required for installation to the detected part is about the same as in the case of one temperature switch. Since the leads and the case are connected using soft lead wires, the reed switch is not constrained to the bottom of the case as much as when the leads are connected directly to the case, and therefore the stress caused by thermal cycles is not applied to the reed switch. In addition, the reeds on the bottom side of the case only need to be cut, and there is no bending, so there is less risk of damaging the reed switch tubular body.

FIG. 3 shows a plan view taken along the line A--A in FIG. 2 of another embodiment of the present invention. The support member 13 is made of a thermally conductive and non-magnetic material,
A groove with an arcuate cross section for fitting the annular temperature-sensitive magnetic bodies 4, 4' is provided in the height direction at the center of both sides, and the other both sides are cylindrical surfaces that fit into the case 5.
The height dimension is approximately the same as the axial dimension of the annular temperature-sensitive magnetic bodies 4, 4'. Temperature switch element 1,
1' is an annular temperature-sensitive magnetic body 4,
It is assembled so that the outer peripheral surface of 4' fits into the groove. Since the support member 13 is in surface contact with the temperature switch elements 1, 1', it is not only easy to assemble, but also useful for positioning the temperature switch elements 1, 1' in the case 5, and is useful for positioning the temperature switch elements 1, 1' within the case 5. Since it also plays the role of transmitting the liquid temperature to 4 and 4', it has the effect of improving responsiveness and reducing the amount of expensive filling resin 6 used.

Note that the lead wire 12 in FIG.
It may be folded back toward the opening side and connected to the case 5 at the stepped portion of the opening. In this case, the leads 2b, 2'b of the reed switch do not need to be provided with a bent portion.

As described above, since the present invention has a structure in which two temperature switch elements are housed in one case, the number of man-hours required for mounting it on the detected part is about the same as in the case of one temperature switch. Moreover, since the two temperature switches each have a predetermined operating temperature, it is only necessary to store the two temperature switches used as individual temperature switches in the case, making it easy to incorporate them into the case. In some cases, it is sufficient to simply align both ends, and alignment for temperature adjustment is not necessary, so the assembly work is simple, and an inexpensive composite temperature switch can therefore be obtained.

[Brief explanation of drawings]

Fig. 1 is a sectional view of an example of a conventional temperature switch for detecting liquid temperature, Fig. 2 is a front sectional view of an embodiment of the present invention, and Fig. 3 is a line A-A in Fig. 2 of another embodiment. It is a plane sectional view corresponding to a line. 1, 1': temperature switch element, 2, 2': reed switch, 3, 3': annular permanent magnet, 4, 4': annular temperature-sensitive magnetic material, 5: bottomed cylindrical case, 6: resin,
7: O-ring, 8: Insulating lid, 9, 9': External connection terminal, 10: Annular metal plate, 11: Adhesive, 1
2: Lead wire, 13: Support member.

Claims (1)

[Scope of utility model registration request] A first temperature switch element having a first operating temperature, which is formed by fitting an annular permanent magnet and an annular temperature-sensitive magnetic material on the outer periphery of the reed switch; A second temperature switch having a second operating temperature different from the first operating temperature is fitted with an annular temperature-sensitive magnetic body, and a second temperature switch having a second operating temperature different from the first operating temperature is installed in a bottomed cylindrical non-magnetic case. The magnets are stored side by side with their axial ends aligned, and a soft lead wire is connected between the leads of one of the reed switches as a bridge, and the lead wire is connected to the case, and the other lead of each of the reed switches is A composite temperature switch in which each lead passes through an insulating cover plate and connects to an external connection terminal.