JPS6318489B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a thermally responsive switch device used in a cooking appliance or the like.

Heat-responsive switch devices that use a temperature-sensitive magnetic material such as magnetic shunt steel whose magnetic permeability drastically decreases due to temperature changes as a temperature detection element are implemented in rice cookers and the like. By the way, in this type of device, since the Kyuri point of the temperature-sensitive magnetic body remains constant, it is not possible to use a temperature adjusting means using an adjusting screw as in a bimetallic switch device. For this reason, the thermally responsive switch device is easily affected by manufacturing variations in dimensional accuracy, assembly accuracy, etc. of each component, and the apparent operating temperature is likely to change. In addition, as mentioned above, conventional devices generally cannot adopt means for adjusting the operating temperature, so when applied to a rice cooker, for example, the change in the apparent operating temperature makes it impossible to obtain a constant product, resulting in burnt rice. The rice cooker may cause the inconvenience of burning or not burning, or it is not possible to provide a rice cooker equipped with a switch device that has an operating temperature that matches the user's preferences, such as whether or not the rice should be browned or the degree of browning. . In particular, a heating space is provided around the pot,
In the case of a rice cooker, etc., in which a heater is placed in this space apart from the pot, and the pot is heated by radiant heat from the heater and heat convection within the space, the pot, which is the heat-sensitive element, is inserted and removed, and the switch device is turned on and off. If there is an adjustment mechanism with a mechanical structure that can adjust the operating temperature because the positional relationship between However, it is extremely difficult and impractical to incorporate this mechanism as it is, and therefore, the above-mentioned disadvantages are conspicuous in this type of rice cooker.

The present invention was developed under the above circumstances.
The purpose is to provide a thermally responsive switch device that can operate accurately at a predetermined temperature by absorbing manufacturing variations due to its extremely simple structure, and also allows the operating temperature to be easily adjusted. There is a particular thing.

An embodiment of the present invention will be described below with reference to FIGS. 1 to 6.

Reference numeral 1 in FIG. 1 is a rice cooker case, which is formed by interposing a heat insulating material 1c between inner and outer case members 1a and 1b. A leg 2a is provided at the lower end of the outer case member 1a.
A bottom plate 2 is fixed thereto, and an operation panel 3 is attached to the side surface of the member 1c. The inner case member 1b has an integral bottom wall 4, and a sheathed heater 5 serving as a heat source is mounted on the upper surface of the support member 6.
etc. Note that 5a is a terminal portion of the heater 5, which is plug-connected to a plug-in terminal 7 provided on the bottom wall 4. Further, reference numeral 8 denotes a pot as a heat-sensitive body, which is inserted into and removed from the case 1. In this embodiment, when the pot 8 is attached to the case 1, it is sealed between the outer periphery of the pot 8 and the inner case member 1b. Space A
, and is heated by the radiant heat of the heater 5 and thermal convection within the space A.

Reference numeral 9 denotes a thermally responsive switch device, which is constructed as follows. In other words, 10 has a knob 1 on one end.
1 is attached, and the intermediate part of these levers is attached to a pivot 13 on a lever support member 12 protruding from the bottom wall 4.
It is rotatably supported via. The knob 11 is inserted through the hole 3a of the operation panel 3 and can be operated from the outside. The lever 10 is rotated counterclockwise in the figure by a torsion coil spring 14 whose one end is engaged with the bottom wall 4 by wrapping a biasing body, for example, a pivot shaft 13, and whose other end is engaged with the lever 10. In other words, a permanent magnet, which will be described later, is biased in a direction away from the pot 8. Further, a switch 15 is disposed near this lever 10, and in this embodiment, this switch 15 is closed by pressing down the knob 11 of the lever 10, and this closing causes the switch 15 to be turned on to the heater 5. It is now possible to energize the The other end of the lever 10 is bent upward, and a permanent magnet 16 is attached to the tip.
On the other hand, a spring receiving plate 17 having a through hole 17a is attached to the center of the bottom wall 4, and an upward cylindrical part 18 with a bent locking part 18a at the upper end is integrally formed opposite to this. It has been done. The upwardly bent portion of the lever 10 is accommodated within the through hole 17a and the upwardly directed cylindrical portion 18. Also, 19 is pot 8
It is a heat-sensitive element that comes into contact with the center of the outer bottom surface of the pot 8, and its lower end is always pushed upward, that is, in the direction of the bottom surface of the pot 8, by the biasing force of a biasing body 20 such as a coil spring supported by the spring receiving plate 17. It is in force. This heat sensitive body 1
As detailed in Fig. 2, 9 has a cylindrical shape with a bottom at one end and an open end, and a temperature-sensitive magnet made of magnetic shunt steel is attached to the inner surface of the cylinder through a heat transfer plate B made of aluminum or the like. It consists of a heat-sensitive body main body 22 having a heat-sensitive body 21 inside, and a temperature adjusting member 23 which is removably attached to the main body 22 by elastic force and whose tip abuts against the pot 8 and adjusts the operating temperature. It has been formed. Furthermore, to explain in detail, the heat sensitive body body 22
The open end of is engaged with the upper end of the biasing body 20, and is also capable of engaging with the locking portion 18a thereof to prevent the upward cylindrical portion 18 from slipping upward. Annular mounting part 2 above the end
4 is formed. Further, the temperature regulating member 23 is, for example, cap-shaped, and the annular mounting portion 2 is disposed in the middle thereof.
For example, an annular engaging portion 25 that removably engages with 4.
is provided, and a bullet landing portion 27 having a plurality of notches 26 is provided below this.
Therefore, the temperature adjusting member 23 is elastically covered with the heat sensitive body 22 by the elastic deformation of the elastic contact portion 27, and the annular engaging portion 25 engages the annular mounting portion 24. It is attached and held in a detachable manner, and the gap G is secured by this attachment. Note that the temperature adjusting member 23 is prepared in advance with different positions of the annular engaging portion 25, and by selecting an appropriate one from among them, it is possible to create a gap G of various sizes when the temperature adjusting member 23 is covered with the heat sensitive body 22. It is now being ensured. Furthermore, the temperature regulating member 23 is not limited to the one shown in FIGS.
As shown in the figure, a temperature control member having a plurality of through holes 28... or a single through hole (not shown) in the contact surface that comes into contact with the bottom of the pot, and the contact surface 2 as shown in FIG.
The temperature regulating member 9 may have a different size from those shown in FIGS. 1 and 2, or may be a temperature regulating member assembled by, for example, wires 30 as shown in FIG.
Furthermore, as shown in FIG. 6, in the structure shown in FIGS. 1 and 2, various types of heat conduction damping members 31 may be housed in the gaps as necessary. It should be noted that each of these modified examples is an example in which consideration is given to making the heat conduction from the pot 8 to the temperature-sensitive magnetic body 21 smaller than that of the heat-sensitive body 19 shown in FIGS. In any of the modifications, various types of through holes 28 with different numbers and sizes, areas of contact surfaces 29, etc. are prepared in advance, and the heat sensitive body 28 can be selected from among them.
Needless to say, it is something that can be installed and maintained. In addition, 29 in the figure is from the heater 5 to the heat sensitive element 19.
This shows a heat shield that blocks radiant heat from entering the area.

When the heat-responsive switch device 9 is set by pushing down the knob 11 with the pot 8 inserted into the case 1, the switch 15 is pressed by the lever 10 and closed, and the torsion coil spring 14 is attached. To overcome the force, the permanent magnet 16 becomes the temperature-sensitive magnetic material 21
adsorbs to. Therefore, the heater 5 is energized and rice cooking begins. When the temperature at the bottom of the pot rises rapidly at the end of rice cooking, the temperature of the temperature-sensitive magnetic body 21 installed inside the heat-sensitive body 19 also rises, and its magnetic permeability sharply decreases. Then, the attraction force acting between the temperature-sensitive magnetic body 21 and the permanent magnet 16 decreases, and when the attraction force becomes smaller than the biasing force of the torsion coil spring 14, the permanent magnet 16 separates from the temperature-sensitive magnetic body 21. Since the lever 10 is displaced downward, the switch 15 is opened and the heater 5 is cut off.

By the way, according to the above structure, heat transfer from the pot 8 to the temperature-sensitive magnetic body 21 is obstructed by the gap G formed by providing the temperature adjustment member 23. Compared to the case where the main body 22 is in direct contact with the bottom of the pot (that is, the conventional method), the thermal conductivity to the temperature-sensitive magnetic body 21 is reduced, and the apparent operating temperature of the device 9 can be increased. Therefore, for example, if the temperature control member 23 is not used and the rice is set not to be browned, by attaching the temperature control member 23, the setting can be made so that the rice is not browned. It can be easily adapted to the user's preferences.

Moreover, if the temperature adjusting member 23 shown in any one of FIGS. 3 to 5 is selected at that time, or
When the heat conduction damping member 31 is housed in the gap G as shown in the figure, the thermal conductivity is smaller than that shown in FIGS. The apparent operating temperature can be obtained. Furthermore, as can be seen from the above, since the apparent operating temperature can be adjusted by adding the temperature adjusting member 23, different air gaps G prepared in advance can be adjusted.
By selecting a desired one from among the plurality of temperature control members 23 forming the switch device 9, manufacturing variations in the switch device 9 can be absorbed and a device that operates accurately at a predetermined temperature can be easily obtained. Moreover,
Adjustment is carried out using the selected temperature control member 2 on the heat sensitive body body 22.
Since the work can be done by simply attaching the parts 3 elastically, the work is extremely easy, and the structure is also extremely simple.

Next, another embodiment of the present invention will be described with reference to FIG. 7 and FIG.
3 has an annular engaging portion 25 formed at its upper end to form a cap shape, and a temperature-sensitive magnetic material 21 and a heat transfer plate B are provided on the inner surface of this member 23 facing the opening at one end of the main body 22. Since the configuration is the same as that of the above-mentioned embodiment except that it is installed through the interior, the explanation will be omitted. The temperature control member 23 in this embodiment includes:
A temperature control member selected from a plurality of temperature control members prepared in advance and containing temperature-sensitive magnetic bodies 21 having different characteristics is used.

Therefore, in the case of this embodiment, although the thermal conductivity from the bottom of the pot 8 to the temperature-sensitive magnetic body 21 is the same, the characteristics of the temperature-sensitive magnetic body 21 are different from each other.
By replacing the temperature control member 23 that incorporates a temperature-sensitive magnetic material 21 with predetermined characteristics, it is possible to adjust the temperature according to the user's preference, such as whether or not to brown the rice, and it is also possible to It is possible to easily obtain a device that absorbs variations in temperature and operates accurately at a predetermined temperature. In this embodiment, the temperature adjusting member 23 may be provided with a snapping part 27 having a notch 26 in the heat sensitive body 22, and fitted into the body 22 to be elastically attached and held.

Further, the present invention is not limited to the above embodiments. For example, the temperature-sensitive magnetic material is not limited to magnetic shunt steel, but may be any temperature-sensitive magnetic material such as ferrite, and the attachment/detachment structure between the temperature control member and the heat-sensitive body is not based on elastic force, but is, for example, a screw type, etc. But it's okay. In addition, the heat-sensitive body is not limited to a pot, and may be a fixed heating plate, and the heat transfer plate B is not necessarily required, and the temperature-sensitive magnetic body is directly connected to the heat-sensitive body or the heat-sensitive body. It may also be attached to the inner surface of the temperature regulating member. If the switch is equipped with a pair of contact springs, the lever may also be configured to serve as one of the contact springs.Of course, a micro switch may also be used as the switch, and in the above example, the switch is configured to open at a predetermined temperature. Alternatively, it may be configured to close at a predetermined temperature. Including these, in carrying out the present invention, the specific structure, shape, position, material of the heat sensitive body, permanent magnet, lever, switch, main body of the heat sensitive body, temperature control member, etc. It goes without saying that the mutual connection relationships and the like can be implemented in various configurations without being limited to the above embodiments.

As explained above, the present invention operates a switch by utilizing temperature-related changes in the magnetic force between a temperature-sensitive magnetic body and a permanent magnet, in which the temperature-sensitive magnetic body is installed inside to operate a switch. The heat sensitive body that comes into contact with the body is formed of a heat sensitive body main body and a temperature adjustment member that is detachably attached and held to the heat sensitive body body and adjusts the operating temperature. Therefore, according to the present invention, it is possible to easily obtain a thermally responsive switch device that absorbs manufacturing variations in the device and operates accurately at a predetermined temperature, and the operating temperature of the device can also be adjusted by adjusting the temperature. This can be easily done by selecting the parts. Furthermore, since the heat-sensitive body that adjusts the temperature has no moving parts, the adjustment is not affected by vibrations or the like during transportation or use.

[Brief explanation of the drawing]

Fig. 1 to Fig. 6 show one embodiment of the present invention, Fig. 1 is a vertical sectional side view of the lower part of the rice cooker, Fig. 2 is an exploded sectional view of the main part, and Fig. 3 to Fig. 5 are different from each other. FIG. 6 is a perspective view of the temperature adjusting member and a sectional view showing the deformation of the heat sensitive body. 7 and 8 show other embodiments of the present invention, with FIG. 7 being a diagram corresponding to FIG. 1, and FIG. 8 being a diagram corresponding to FIG. 2. 8... Heat sensitive body (pot), 9... Heat responsive switch device, 10... Lever, 14... Torsion coil spring, 15... Switch, 16... Permanent magnet, 19
. . . Heat sensitive body, 22 .

Claims (1)

[Scope of Claims] 1. A heat-sensitive body that has a temperature-sensitive magnetic body inside and comes into contact with a heat-sensitive body, a permanent magnet that comes into contact with and separates from the temperature-sensitive magnetic body of this heat-sensitive body, and a permanent magnet that supports this magnet. The heat sensitive body includes a lever and a switch operated by the lever, and the heat sensitive body has a temperature adjusting member whose tip abuts on the heat sensitive body and adjusts the operating temperature.
A heat-responsive switch device characterized in that it is formed by being detachably attached to and held on a heat-sensitive body. 2. The thermally responsive switch device according to claim 1, wherein the temperature adjusting member is removably attached to the heat sensitive body by elastic force. 3. The heat-sensitive body has a cylindrical shape with a bottom at one end and an open end at the other end, and the temperature-sensitive magnetic body is housed inside the body, as set forth in claim 1. Thermal response switch device. 4. Claim 1, characterized in that the heat-sensitive body has a cylindrical shape with both ends open, and the temperature-sensitive magnetic body is housed in the temperature adjustment member opposite to the opening at one end. The thermally responsive switch device described in . 5. In the thermally responsive switch device as set forth in claim 4 above, the temperature regulating member is selected from a plurality of temperature regulating members prepared in advance and each containing a temperature-sensitive magnetic material having different characteristics. A thermally responsive switch device characterized by: