JPS5926502Y2 - Cooker thermostat - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an improvement of a thermostat for a cooker that utilizes the Curiosity temperature of ferrite.

In cooking appliances such as rice cookers, this type of thermostat is generally used as a thermostat that senses the completion of cooking of rice (dish).

That is, the electric circuit is controlled by operating the magnet attracted to the ferrite at the Curie temperature at which the ferrite loses its magnetism.

By the way, in this type of thermostat, since the operating temperature changes when the relative position between the ferrite and the magnet changes, the relative position between the ferrite and the magnet must be accurately regulated so as not to deviate.

For this reason, conventional thermostats use guide pins to regulate the magnet's operation, but this structure of regulating the position of the magnet using guide pins or other means reduces the productivity of the thermostat and causes malfunction. It causes

In view of this point, the present invention aims to provide a structure that does not require means for regulating the position of the magnet.

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

Reference numeral 1 is a cylindrical case of the thermostat, and 2 is a heat-sensitive plate attached to the upper opening of the thermostat, which comes into contact with the bottom surface of a cooking pot (not shown).

Reference numeral 3 denotes a ferromagnetic plate according to the present invention, which is provided in close contact with the back surface of the heat-sensitive plate 2, and is supported at the opening of the case 1 by a support plate 4.

5 and 5' are a pair of ferrites fixed to the lower surface of the ferromagnetic plate 3.

Reference numeral 6 denotes a magnet that comes into contact with the lower surface of the ferrites 5, 5', and its periphery is held by a retainer 7.

The retainer 7 has an operating shaft 8 exposed to the outside of the case 1 at its center, and a ring-shaped spring receiver 9 is provided around the operating shaft 8, and a ring-shaped spring receiver 9 is provided between the spring receiver 9 and the support plate 4. A coil spring 10 is provided which is biased to push the retainer 7 downward.

Next, its effect will be explained.

The magnet 6 forms a magnetic circuit via the ferrite 5.5' and the ferromagnetic plate 3, and is attracted to the ferrite 5 and 5' by overcoming the pushing force of the coil spring 0.

Now, when the cooking pot (not shown) reaches a predetermined temperature, that is, one curie temperature of the ferrite 5.5', the heat sensitive plate 2 detects this and transmits it to the ferrite 5.5' via the ferromagnetic plate 3. ) 5.5' does not lose its magnetism, and the magnetic circuit of the magnet 6 is interrupted.

Therefore, the magnet 6 does not lose its attraction force to the magnet 5.5', the retainer 7 is pushed down by the coil spring 10, and the operating shaft 8 acts on a switch mechanism (not shown).

Since the present invention has the above-described structure and operation, it has the following effects.

That is, this type of thermostat generally uses two ferrites to stabilize the operating temperature.

By the way, in conventional thermostats, the position where the magnet attracts changes due to variations in the magnetism of the two ferrites, so the operation of the magnet is regulated using position regulating means such as a guide pin.

In contrast, in the present invention, the two ferrites 5,5' are integrated by the ferromagnetic plate 3, so the magnet 6 comes into contact with the ferrites 5,5', which have uniform magnetic properties, and there is no change in the adsorption position. Therefore, no position regulating means such as the guide pin is required.

The ring-shaped spring receiver 9 is guided in sliding contact with the inner surface of the cylindrical case 1, and the retainer 7 is moved up and down.

As described above, the present invention does not require a magnet position regulating means, which simplifies the structure, improves productivity, and eliminates malfunctions caused by the magnet position regulating means.

Furthermore, it has many excellent effects, such as reducing the coupling design force of the operating shaft 8 to the switch mechanism.

[Brief explanation of drawings]

Figure 1: Longitudinal sectional view of the embodiment of the present invention, Figure 2: Figure 1
A horizontal cross-sectional view taken along the Y line in the direction of the arrow a, FIG. 3: A horizontal cross-sectional view taken along the XY line in FIG. 1 in the direction of the arrow A. 1... Case, 2... Heat sensitive plate, 3...
...Ferromagnetic plate, 4...Support plate, 5,5'.
...Ferrite, 6...Magnet, 7
...Cage, 8...Movement axis, 9...
... Spring holder, 10 ... Coil spring.

Claims (1)

[Scope of utility model registration request] A heat-sensitive plate is provided at the top opening of the case, a pair of ferrites are attached to a ferromagnetic plate provided closely on the back side of the heat-sensitive plate,
A holder is provided that holds a magnet in contact with the ferrite and has an operating axis exposed outside the case, and the holder is moved between the holder and the case against the attraction force of the magnet to the ferrite. A thermostat for a cooker that utilizes the temperature of a ferrite cucumber, characterized in that it is provided with a coil spring that acts to push the temperature downward.