JPS6248337B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a temperature-sensitive switch that combines a reed switch, a permanent magnet, and a temperature-sensitive magnetic material. The present invention relates to a switch (hereinafter simply referred to as a make-type temperature-sensitive switch).

2. Description of the Related Art Temperature-sensitive switches having various functions have been known in the past, and a make-type temperature-sensitive switch having a structure as shown in FIG. 1 is generally known.

Here, a conventional make-type temperature-sensitive switch will be explained with reference to FIG. 1. As shown in the figure, an annular temperature-sensitive magnetic material 3 is arranged between both ends of an annular magnetic gap material 4 made of a non-magnetic material. Further, a pair of annular permanent magnets 2 are arranged so as to sandwich the temperature-sensitive magnetic body 3. The reed switch 1 is inserted and fixed into the annular body, and at this time the magnetic gap material 4
corresponds to the opening/closing contact portion 11 of the reed switch 1. As shown in the figure, the permanent magnets are magnetized so that the end faces facing each other have different magnetic poles. The contact of this temperature-sensitive switch is closed (made) when the temperature reaches a predetermined Curie temperature or higher. Furthermore, the operating temperature of the temperature-sensitive switch can be changed by changing the gap between the magnetic gap members 4.

However, the make-type temperature-sensitive switch mentioned above has become expensive due to the large number of parts.
Furthermore, there is also the problem that the temperature-sensitive switch itself becomes larger.

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide an inexpensive and compact temperature-sensitive switch with a small number of parts.

According to the present invention, a reed switch has an opening/closing contact portion formed of a magnetic reed piece, a temperature-sensitive magnetic body disposed on the reed switch in correspondence with the contact portion, and a temperature-sensitive magnetic body disposed on the reed switch in correspondence with the contact portion; It has first and second permanent magnets arranged to sandwich a warm magnetic material, the magnetization direction of the first permanent magnet is parallel to the axis of the reed switch, and the magnetization direction of the first permanent magnet is parallel to the axis of the reed switch. The magnetization direction of the permanent magnet is a magnetic pole line from the magnetic pole on the side of the temperature-sensitive magnetic body of the first permanent magnet to the magnetic pole on the side away from the temperature-sensitive magnetic body, and the magnetic pole line of the second permanent magnet on the side of the temperature-sensitive magnetic body. The magnetic pole line from the magnetic pole on the remote side to the magnetic pole on the temperature-sensitive magnetic body side intersects at an acute angle, and furthermore, the first and second permanent magnets have different magnetic poles on the opening/closing contact side. A temperature-sensitive switch is obtained, which is characterized in that:

The present invention will be explained below with reference to embodiments shown in the drawings.

First of all, referring to FIG. 2 which shows the first embodiment of the present invention, the opening/closing contact part 1 is composed of magnetic lead pieces.
1 is sealed in a glass tube 14 to constitute a reed switch 1. A prismatic temperature-sensitive magnetic body 3 is fixed to the surface of the reed switch 1 at a position relative to the opening/closing contact portion 11 . Further, two prismatic permanent magnets 5 and 6 are fixed on the surface of the reed switch 1 so as to sandwich the temperature-sensitive magnetic body 3 therebetween. As shown, the magnetization direction of the permanent magnet 5 is parallel to the axis of the reed switch 1, and the magnetization direction of the permanent magnet 6 is arranged to intersect the axis of the reed switch 1 at an acute angle. That is, the magnetization direction of the permanent magnet 6 is a magnetic pole line from the magnetic pole on the temperature-sensitive magnetic body 3 side of the permanent magnet 5 to the magnetic pole on the side away from the temperature-sensitive magnetic body 3, and a magnetic pole line that is separated from the temperature-sensitive magnetic body 3 of the permanent magnet 6. This is the direction in which the magnetic pole lines from the magnet on the opposite side to the magnetic pole on the temperature-sensitive magnetic body 3 side intersect at an acute angle.
Specifically, the permanent magnet 6 is arranged on the surface of the reed switch 1 so that the magnetization direction always passes through the opening/closing contact portion 11. Further, as shown in the figure, the parts (surfaces) of the permanent magnets 5 and 6 near the opening/closing contact part 11 of the reed switch 1 have different magnetic poles (in the case of FIG. 2, the permanent magnet 5 is N
The permanent magnet 6 is the south pole. ).

Next, the operation of this temperature-sensitive switch will be explained with reference to FIGS. 3 and 4.

When the temperature of the temperature-sensitive magnetic material 3 is lower than the predetermined Curie point of the temperature-sensitive magnetic material 3, the magnetic resistance value of the temperature-sensitive magnetic material is small (the permeance is large), as shown in FIG. As such, the lines of magnetic force coming out from the N pole of the permanent magnet 6 enter the S pole of the permanent magnet 5, and from the N pole of the permanent magnet 5 pass through the temperature sensitive magnetic body 3 to reach the S pole of the permanent magnet 6. At this time, as shown in the figure, a line of magnetic force comes out from one end of the temperature-sensitive magnetic body 3 (permanent magnet 6 side) into the reed switch, and the S of the permanent magnet 6
Although it enters the pole, the switching contact portion 11 is magnetized by this, and the switching contact portion 11 does not close. Furthermore, as shown in the figure, since the N pole of the permanent magnet 6 is located at the upper part of the figure, the number of magnetic lines of force (that is, magnetic flux) passing through the reed switch is very small, and this also causes the switching contact part 11 to become magnetized. Therefore, the opening/closing contact portion 11 never closes. Therefore, reed switch 1
is in an open state until the temperature of the temperature-sensitive magnetic body 3 exceeds the Curie point.

When the temperature of the temperature-sensitive magnetic body 3 exceeds the Curie point, the magnetic resistance of the temperature-sensitive magnetic body 3 increases rapidly (that is, the permeance decreases). Therefore, as shown in FIG. 4, the lines of magnetic force from the N pole of the permanent magnet 5 to the S pole of the permanent magnet 6 hardly pass through the temperature-sensitive magnetic body 3, but instead pass through the reed switch 1, and are Therefore, the switching contact portion 11 is magnetized, and the switching contact portion 11 is closed. In this way, a make-type temperature-sensitive switch is obtained in which the contact is made when the temperature of the temperature-sensitive magnetic body 3 becomes equal to or higher than the Curie point.

FIG. 5 shows a second embodiment of the invention. The illustrated temperature-sensitive switch has an annular temperature-sensitive magnetic body 3 sandwiched between annular permanent magnets 7 and 8, and a reed switch 1 inserted into the center of the magnet and fixed therein. It is arranged so as to correspond to the body 3. Further, as in the first embodiment, the direction of magnetization of the permanent magnet 7 is parallel to the axis of the reed switch 1, and the direction of magnetization of the permanent magnet 8 is perpendicular to the axis of the reed switch 1. Further, the parts (surfaces) of the permanent magnets 7 and 8 close to the opening/closing contact portion 11 of the reed switch 1 have different magnetic poles. By configuring the temperature-sensitive switch using the annular temperature-sensitive magnetic body and permanent magnet in this manner, the influence of external magnetic fields can be reduced. Also,
In the make-type temperature-sensitive switch shown in FIG. 5, the temperature at which the switching contact section 11 changes from an open state to a closed state (make temperature) is different from the temperature at which it changes from a closed state to an open state (break temperature). The latter is larger.

FIG. 6 shows a third embodiment of the present invention. This embodiment is a temperature-sensitive switch in which two temperature-sensitive magnetic bodies 9 and 10 are arranged as shown in the figure, instead of the temperature-sensitive magnetic body 3 of the second embodiment shown in FIG. The temperature-sensitive magnetic bodies 9 and 10 have different Curie points, and therefore can increase the difference between the make temperature and the break temperature.

Figures 7a and 7b show a fourth embodiment according to the invention. First, in the embodiment shown in FIG. 7a, instead of the permanent magnet 8 of the second embodiment shown in FIG. A permanent magnet 12 formed so as to be substantially parallel to the magnetization direction is arranged. In addition, in the embodiment shown in FIG. 7b, the end face of the permanent magnet 12 in contact with the temperature-sensitive magnetic body 3 of the embodiment shown in FIG. One end surface of the temperature-sensitive magnetic body 3 is formed so as to come into contact with an end surface formed substantially parallel to the temperature-sensitive magnetic body 3 . In these temperature-sensitive switches, the permeance of the permanent magnets 12 and 13 can be increased, and the hysteresis of the permanent magnets 12 and 13 can be reduced at low temperatures (the temperature at which the switching contact portion 11 is in the open state).

FIGS. 8a and 8b show a fifth embodiment of the present invention. FIG. 8a shows a temperature-sensitive switch in which a magnetic gap 14 is provided between the temperature-sensitive magnetic body 3 and the permanent magnet 8 in the temperature-sensitive switch shown in FIG.
Similarly, FIG. 8b shows a temperature-sensitive switch in which a magnetic gap 14 is provided between the temperature-sensitive magnetic body 3 and the permanent magnet 7. In these temperature-sensitive magnetic materials, by changing the thickness of the magnetic gap 14, it is possible to change the operating temperature within a certain range.

In the first to fifth embodiments, it is possible to change the operating temperature of the temperature-sensitive switch by changing the angle at which the axis of the reed switch intersects with the direction of magnetization of the permanent magnet.

As explained above, according to the present invention, it is possible to provide a small and inexpensive make-type temperature-sensitive switch with fewer parts than conventional switches, and the degree of freedom of the opening/closing contact is large, that is, positioning of the reed switch is easy. We can provide a make-type temperature-sensitive switch.

[Brief explanation of the drawing]

Fig. 1 is a sectional view showing a conventional make-type temperature-sensitive switch, Fig. 2 is a sectional view showing a first embodiment of the present invention, and Figs. 5 is a sectional view showing the second embodiment of the present invention; FIG. 6 is a sectional view showing the third embodiment of the present invention; FIG. 7a
8a and 8b are cross-sectional views showing a fourth embodiment according to the present invention, and FIGS. 8a and 8b are cross-sectional views showing a fifth embodiment according to the present invention. 1...Reed switch, 2, 5, 6, 7, 8, 1
2, 13... Permanent magnet, 3, 9, 10... Temperature-sensitive magnetic material, 11... Opening/closing contact portion, 4... Magnetic gap material, 14...
magnetic gap.

Claims (1)

[Claims] 1. A reed switch having an opening/closing contact portion formed of a magnetic reed piece, a temperature-sensitive magnetic material disposed on the reed switch in correspondence with the contact portion, and a temperature-sensitive magnetic material placed on the reed switch. It has first and second permanent magnets arranged in a sandwiched manner, the direction of magnetization of the first permanent magnet is parallel to the axis of the reed switch, and the direction of magnetization of the second permanent magnet is parallel to the axis of the reed switch. A magnetic pole line from the magnetic pole on the temperature-sensitive magnetic body side of the first permanent magnet to a magnetic pole on the side away from the temperature-sensitive magnetic body, and a magnetic pole line on the side of the second permanent magnet that is remote from the temperature-sensitive magnetic body. The direction is such that the magnetic pole line toward the magnetic pole on the temperature-sensitive magnetic body side intersects at an acute angle, and further, the first and second permanent magnets have different magnetic poles from each other on the opening/closing contact portion side. Features a temperature-sensitive switch.