JPH03144217A - Heater-cooker - Google Patents

Abstract

PURPOSE:To prevent the trouble of a hand or the like getting burnt by touching an electric heater while the heater is hot, by operating a switch by a deformation of a heat-responsive member making contact with an end part of the heater at or above a predetermined temperature, and thereby informing the user that the temperature of the heater is high. CONSTITUTION:A heat-responsive member 9 to be deformed by receiving heat from an end part 4a of an electric heater 4 is provided in contact with the end part 4a. A switch 10 capable of operating in response to a deformation of the heat-responsive member 9 when the end part 4a is at or above a predetermined temperature is provided, and an alarm means 11 for issuing an alarm through the operation of the switch 10 is provided. Therefore, the user can see whether the heater 4 is at a high temperature, based on the presence or absence of the alarm from the alarm means 11. A maximum temperature of the end part 4a of the heater 4 is lower than that of a heat generating part for heating a matter to be cooked in a heating chamber, there is no possibility that the heat-responsive member 9 may have a permanent set due to thermal strain. The user is thus prevented from getting burnt.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a cooking device that includes an electric heater in a heating chamber.

(Prior Art) Some heating cookers, such as microwave ovens, are equipped with an electric heater in a heating chamber to perform grill cooking. In this case, a sheathed heater is generally used as the electric heater.

(Problems to be Solved by the Invention) By the way, a sheathed heater exhibits a dark color when it is cold, and becomes red hot when energized. When the sheathed heater is turned off, it returns to its normal dark color, but due to its heat capacity, the temperature remains high for some time after that. In this way, it is difficult to tell whether the sheathed heater is in a high temperature state or a cold state just by the color of the sheathed heater.
However, when the sheathed heater is dark in color, the user tends to think that it is cold.

Therefore, when the user puts his/her hand into the heating chamber to clean it after cooking, there is a risk that the user may touch the sheathed heater, which is still at a high temperature, and suffer burns.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a heating cooker that can display a message when the electric heater is at a high temperature to alert the user to prevent burns. .

[Structure of the Invention] (One Step for Solving the Problems) The heating cooker of the present invention is one in which an electric heater is provided in the heating chamber, and the heating device contacts the mouth part of the electric heater to absorb the heat of the mouth part. a thermally responsive member that deforms in response to the electric heater; a switch that operates in response to the deformation of the thermally responsive member when the mouth portion of the electric heater is at a predetermined temperature or higher; and an alarm means that operates to notify when the switch is activated. It is characterized by having the following.

(Function) When the temperature of the electric heater is high, the temperature of the mouth portion of the electric heater is equal to or higher than a predetermined temperature.

The switch is actuated by the deformation of the thermally responsive member in contact with the mouth portion, and the notification means performs a notification operation to notify that the temperature of the electric heater is high.

When the temperature of the electric heater decreases to a level where there is no danger of burns, the temperature at the mouth of the electric heater also decreases, and the thermally responsive member disables the switch, so that the notification means stops the notification operation. Therefore, the user can know whether or not the electric heater is in a high temperature state based on the presence or absence of the notification operation of the notification means.

In this case, since the maximum temperature of the mouth portion of the electric heater is lower than that of the heat generating portion that heats the food to be cooked in the heating chamber, there is no risk of permanent deformation of the thermally responsive member due to thermal strain.

(Example) Hereinafter, an example in which the present invention is applied to a microwave oven will be described with reference to the drawings.

First, in FIGS. 5 and 6 showing the overall configuration of a microwave oven, a heating chamber 2 is formed inside a main body 1, and a turntable 3 is disposed at the inner bottom of this heating chamber 2. A sheathed heater 4, which is an electric heater, is also provided in the upper part. In addition, a heating chamber 2 is provided on the entire surface of the main body 1.
A door 5 for opening and closing is pivotally provided, and an operating section 6 is provided to the right of the door Df5.

Now, in FIGS. 1 and 2, the sheathed heater 4
The mouth portion 4a of the heating chamber 2 is supported by a support plate 7 fixed to the back surface of the heating chamber 2, and protrudes rearward from the back surface of the heating chamber 2, and the terminal 4b at the tip of the mouth portion 48 is connected to a connector (not shown). It is connected. A mounting plate 8 fixed to the outside of the back surface of the heating chamber 2 so as to be located near the opening 4a of the sheathed heater 4 has one end of a thermally responsive plate 9 made of a shape memory alloy as a thermally responsive member. is fixed, and the tip side of this thermally responsive plate 9 is connected to the mouth 4a of the sheathed heater 4.
It touches the part from above. This heat-responsive plate 9
When part a is at a predetermined temperature or higher (corresponding to the temperature when the temperature of the part located in the heating chamber 2 is about 40°C or higher), it has a straight, normal shape as shown in Figure 3. When the temperature exceeds the predetermined temperature, it is configured to deform into a downwardly curved memorized shape as shown in FIG. Further, a microswitch 10 as a switch element is attached to the mounting plate 8 so as to be located directly below the thermally responsive plate 9. When the thermally responsive plate 9 is in its normal shape, the microswitch 10 is The microswitch 10 is turned off by moving away from the button 10a, and when it is transformed into the memorized shape, the button 10a is pressed and the microswitch 10 is turned off.
is turned on to operate. On the other hand, on the back side of the operating section 6, a lamp 12 is attached that functions as a display source for a display device 11, which is a notification means and is connected in series with a microswitch 10 to a power source. This lamp 12 is
It is covered by a cover 13, and the light from the lamp 12 is focused by the cover 13 onto the base ends of a number of glass fibers 14 which are attached in a bundle to the front part of the cover 13. The tip of the glass fiber 14 is connected to the operating section 6.
They are arranged and attached to the back side of a semi-transparent display board 15 provided at the top of the screen to form the words "Grill Heater Hot".

Next, the operation of the above configuration will be explained.

As shown in FIG. 3, a grill grate 16 with legs for grill cooking is placed on the turntable 3, food to be cooked is placed on the grill grate 15, and the sheathed heater 4 is energized in this state. Then, the sheathed heater 4 becomes red hot and grills the food. Due to this energization, the temperature of the mouth portion 48 of the sheathed heater 4 becomes higher than the predetermined temperature, so the thermally responsive plate 9 is deformed into a memorized shape as shown in FIG. 4, and the button 10a of the microswitch 10 is pressed. . As a result, the micro switch 10
turns on and energizes the lamp 12, so the lamp 12
is lit. The light from the lamp 12 is guided to the glass fiber 14, and a message γ indicating "Grill heater is hot" appears on the display board 15.

Now, when the grill cooking is finished, the sheathed heater 4 is turned off. Due to this power cut, the sheathed heater 4 turns dark to its normal color in a short time, but its temperature remains high for a while. Therefore, the thermally responsive plate 9 maintains its deformed state as shown in FIG.
The words "Grill Heater Hot" remain displayed on the screen.

When the sheathed heater 4 cools down to about 40° C. or below, the temperature at the mouth 48 becomes below the predetermined temperature, so the thermally responsive plate 9 returns to its original state as shown in FIG. As a result, the microswitch 10 is turned off, the lamp 12 disappears, and the display on the display board 15 also disappears.

In this way, when the sheathed heater 4 is hot, the display board 1
A display to that effect is displayed on the display panel 5, and the display disappears when the heater cools down, so that the user can judge whether or not the sheathed heater 4 is hot based on the display on the display panel 15. For this reason,
It is possible to prevent problems such as cleaning the inside of the heating chamber 2 while the sheathed heater 4 is hot and touching the sheathed heater 4 and getting burned.

Further, in this embodiment, since the thermally responsive plate 9 is brought into contact with the mouth portion 4a of the sheathed heater 4, the temperature detecting function of the thermally responsive plate 9 can be normally performed over a long period of time.

That is, the temperature of the heat generating portion of the sheathed heater 4 located in the heating chamber 2 changes in the range from room temperature to about 700 to 800°C.

When the thermally responsive plate 9 is brought into contact with such a large temperature change area, the thermally responsive plate 9 made of a shape memory alloy will be permanently deformed due to thermal distortion, and will not return to its original shape even when the sheathed heater 4 cools down to room temperature. There is a risk that problems such as failure to return may occur. However, the temperature of the mouth part 4a does not change as much as mentioned above, and the temperature ranges from room temperature to about 100 degrees Celsius at most, so there is no risk that the heat-responsive plate 9 made of shape memory alloy will be permanently deformed due to thermal distortion, and it will last for a long time. works fine.

Note that the thermally responsive member is not limited to one made of shape memory alloy, but may be made of bimetal.

In addition, the present invention is not limited to the embodiments described above and shown in the drawings; for example, the notification section may be a buzzer, etc., and is not limited to microwave ovens, but can be widely applied to cooking devices in general. It can be implemented with various modifications without departing from the gist thereof.

[Effects of the Invention] As explained above, according to the present invention, a thermally responsive member is provided that contacts the mouth portion of the electric heater and deforms by receiving heat from the mouth portion, and when the electric heater is at a predetermined temperature or higher, We have provided a switch that is activated by the deformation of the heat-responsive member of the heater, and we have provided an alarm means that activates the alarm when the switch is activated.This effectively prevents the problem of burns caused by touching the electric heater while it is hot. It can be prevented. In addition, since the thermally responsive member is in contact with the mouth of the electric heater, where temperature changes are relatively small, there is no risk of permanent deformation due to thermal distortion, and it has the advantage of maintaining normal temperature detection operation over a long period of time. It has the following effects.

[Brief explanation of the drawing]

The drawings show one embodiment of the present invention; FIG. 1 is a vertical cross-sectional side view showing the main parts, FIG. 2 is an exploded perspective view of the main parts, and FIGS. FIG. 5 is a perspective view of the microwave oven, and FIG. 6 is a front view of the same with the door open. In the figure, 2 is a heating chamber, 4 is a sheathed heater (electric heater),
9 is a thermally responsive plate (thermally responsive member), 10 is a microswitch, 11 is a display device (notification means), 12 is a lamp, 14 is a glass fiber, and 15 is a display board. Figure 1 9 Figure 2 Figure 3 Figure 4 Figure 5 Figure 6

Claims (1)

[Claims] 1. In a heating chamber provided with an electric heater, there is a thermally responsive member that contacts the mouth portion of the electric heater and deforms in response to heat from the mouth portion, and the mouth portion of the electric heater is at a predetermined temperature or higher. A heating cooking device comprising: a switch that operates in response to the deformation of the thermally responsive member; and a notification device that performs a notification operation in response to the operation of the switch.