JPH0420353Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a temperature sensor for a cooker having a function of preventing cooking from drying.

[Conventional technology]

An example of a conventional temperature sensor for a cooker is shown in FIG. Referring to Fig. 6, thermistor holding fitting 2
and the inner case 17 are fixed by caulking the ends of the lid 1. A thermistor 3 is located between the lid 1 and the presser fitting 2. A non-magnetic metal case 7 for inserting a reed switch is fixed to the lower surface of the presser metal fitting 2. An insulating tube 8 is placed inside the non-magnetic metal case 7, a reed switch 9 is inserted into the insulating tube 8, and then the tip of the non-magnetic metal case 7 is caulked and fixed.

On the other hand, a ring magnet 6 is fixed to the bottom of the outer case 5. Inner case 17 and outer case 5
A compression coil spring 4 is interposed between the two. The upward movement of the inner case 17 is prevented by its collar 20 engaging the outer case 5. The outer case 5 is fixed to an outer pot (not shown).

When the inner pot (not shown) is mounted on the top surface of the lid 1, the reed switch 9 is lowered together with the inner case 17 and the non-magnetic metal case 7. On the other hand, when the inner pot is removed, the reed switch 9 is raised. As a result, the contacts of the reed switch 9 open and close.

When the inner pot is not placed, the magnet 6 faces the contact part of the reed switch 9, as shown in FIG. 7, and as a result, the contact part of the reed switch 9 is closed by the magnetic flux from the magnet 6. There is. Next, when the inner pot is placed, the contacts of the reed switch 9 are opened, contrary to the above. The opening/closing signal of the reed switch 9 is processed by an external circuit to cut off power to the heater and the like. For example, when the contact of the reed switch 9 is opened, processing is performed by an external circuit so that the heater or the like is energized. In other words, when the inner pot is not placed, electricity is not applied to prevent dry cooking.

[Problem that the invention attempts to solve]

However, in the cooker temperature sensor shown in FIG. 6, a total of four wires, the lead wire 10 from the thermistor 3 and the lead wire 11 from the reed switch 9, are drawn out to the outside of the sensor for parallel connection to an external circuit. Therefore, the workability of sensor assembly is poor. In addition, since as many as four wires are drawn out, there is a high probability of failure due to tensile force, resulting in a problem of low reliability.

[Means for solving problems]

According to the present invention, a cooker includes a thermistor that detects the temperature of a heated object, a reed switch, and a magnetic flux generator that applies controlled magnetic flux to the reed switch depending on whether the heated object is mounted. The temperature sensor has a built-in mounting board on which the reed switch is mounted, the reed switch is connected to the conductor part of the mounting board, and the lead wire of the thermistor is also connected, and the lead wire is connected to the conductor part of the mounting board to the outside. A temperature sensor for a cooker characterized in that the wire is led out to the outside is obtained.

〔Example〕

An embodiment of a temperature sensor for a cooker according to the present invention is shown in FIG. The temperature sensor shown in the drawing includes a mounting board 12 on which a conductor part 13 for wire connection is printed. The conductor portion 13 may be formed on a printed board added to the mounting board 12. A reed switch 9 and a fixed magnet 14 are fixed to this mounting board 12 as shown in FIG. At this time, the lead wire of the reed switch 9 is connected to the conductor portion 13. Further, the fixed magnet 14 is located near the reed switch 9. After that, attach the mounting board 14 to the mounting bracket 15 shown in FIG.
The lead wire 31 of the thermistor 3 and the external wire 16 are connected to the conductor portion 13 by soldering to obtain the structure shown in FIG. 4. The structure shown in FIG. 4 is then fixed to the lid 1 together with the inner case 17 as shown in FIG. Connect with.

In terms of the electrical circuit, as shown in Figure 5, thermistor 3
and reed switch 9 are connected in parallel to each other. In terms of the magnetic circuit, the fixed magnet 14 is placed at a position where its magnetic flux closes the contact of the reed switch 9. The bias magnet 21 is arranged in a polarity different from that of the fixed magnet 14. Now, lid 1 is pressed and lowers,
When approaching the bias magnet 21, the magnetic flux flowing from the fixed magnet 14 to the reed switch 9 is attracted to the bias magnet 21, and as a result, the contacts of the reed switch 9 are opened. Lid 1
When the pressing force is released, the reed switch 9 and the fixed magnet 14 are lifted by the restoring force of the compression coil spring 4 and returned to their original states.

According to the above structure, since the mounting board 12 is provided and the reed switch 9 is placed horizontally, all of the leads, lead wires, and external lead wires are connected to the conductor portion 13.
Connected with Further, since the reed switch 9 and the magnet 14 are placed so as to be visible on the mounting board 12, they can be easily set and aligned with high precision. Therefore, even if the bias magnets 21 are in a bad position and do not attract each other, it is fail-safe.

[Effect of idea]

As described above, according to the present invention, the reed switch is compact and the contacts of the reed switch can be reliably switched.
It has now become possible to provide a temperature sensor for cooking appliances that is highly safe, resistant to wire tension, and has a highly reliable function to prevent dry cooking.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal cross-sectional view of one embodiment of the temperature sensor for a cooker according to the present invention, Fig. 2 is a perspective view showing the assembled state of the parts used, Fig. 3 is a perspective view of other parts, and Fig. 4. is a longitudinal sectional view showing the assembled state of the parts in Fig. 2 and the parts in Fig. 3, Fig. 5 is a diagram for explaining the action of the temperature sensor in Fig. 1, and Fig. 6 is a diagram showing the temperature sensor for a conventional cooking device. FIG. 7, which is a longitudinal cross-sectional view of an example of the sensor, is also an action explanatory diagram. 3...Thermistor, 4...Compression coil spring, 5
...Outer case, 9...Reed switch, 12...
Mounting board, 13... Conductor portion, 14... Fixed magnet, 15... Mounting bracket, 16... External lead wire, 17... Inner case, 21... Bias magnet, 31... Lead wire.

Claims (1)

[Scope of Claim for Utility Model Registration] 1. A thermistor that detects the temperature of a heated object, a reed switch, and a magnetic flux generator that applies controlled magnetic flux to the reed switch depending on whether or not the heated object is mounted. A temperature sensor for a cooker comprising a built-in mounting board on which the reed switch is mounted, the reed switch is connected to the conductor part of the mounting board, and the lead wire of the thermistor is also connected, and the conductor part of the mounting board is connected to the lead switch of the thermistor. A temperature sensor for a cooker, characterized in that an external wire is led out from the. 2. The magnetic flux generating device includes a first magnet that moves depending on whether or not a heated object is mounted, and a second magnet that faces the first magnet in its movable direction. The temperature sensor for a cooker according to claim 1), wherein the second magnets are magnetized in a direction in which they attract each other.