JPS6342162B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a stove with a boiling point detection device that indirectly detects the boiling point of water in a heating container by detecting the temperature of the heating container.

Conventionally, as shown in FIG. 1, this type of cooking stove with a boiling point detection device has a boiling point detection device 3 disposed approximately in the center of a spiral heater 2 supported by a holding fitting 1. The boiling point of water in the heating container 4 was detected by detecting the temperature at the bottom of the heating container 4. In addition, 5 is a temperature sensing element provided in the boiling point detection device 3.

The operating principle of the above configuration is that when the amount of water in the heating container 4 is large, the heating container 4 is heated by the heater 2.
Most of the heat added to the water is used to raise the temperature of the water, and in this case, the temperature of the water gradually rises due to the large amount of water, and during this time, the temperature sensing element 5 of the boiling point detection device 3 Since the water receives radiant heat from the heater 2, the temperature detected by the temperature sensing element 5 increases faster, and increases almost in proportion to the temperature of the water. Therefore, when the amount of water in the heating container 4 is large, the boiling point of the water can be detected with high accuracy by detecting the temperature at the bottom of the heating container 4 with the boiling point detection device 3.

However, when the amount of water in the heating container 4 is small, most of the heat added to the heating container 4 by the heater 2 is used to raise the temperature of the water, and the temperature of the water also increases because the amount of water is small. It is relatively quick to reach its boiling point. In this case, since the heated heating container 4 is transmitted to the temperature sensing element 5 of the boiling point detection device 3 via the heat receiving plate and the insulating plate, the temperature increase detected by the temperature sensing element 5 is delayed by that amount. . That is, according to the conventional boiling stove equipped with a boiling detection device, when the amount of water in the heating container 4 is small, the temperature sensing element 5 shown by the dashed-dotted line responds to the actual water temperature change shown by the solid line in FIG.
The detected temperature change is delayed, and the boiling point is erroneously detected at time b, which is later than the actual boiling time B.

Thermal conductivity also changes depending on the material of the heating container 4, but even if a heating container 4 with particularly poor thermal conductivity is used, the boiling temperature will be lower than the actual boiling time as described above. The boiling point was detected incorrectly.

As described above, in the conventional stove with a boiling detection device, when the amount of water in the heating container 4 is small, the boiling point detected by the boiling point detection device 3 deviates greatly from the actual boiling point. Further, there was a problem in that the heating container 4 was affected by differences in the material, etc. of the heating container 4.

The present invention has been made to solve the above-mentioned conventional problems, and is provided with a heater for heating the temperature sensing element for a certain period of time after the heating means for heating the heating container starts heating. Then,
It is an object of the present invention to provide a stove with a boiling point detection device that can accurately detect the boiling point regardless of the amount of water in the heating container and the material of the heating container.

Hereinafter, one embodiment of the present invention will be described based on the accompanying drawings. In Fig. 3, 1 is a holding metal fitting, 2
is a spiral heater held by a holding metal fitting 1, and a boiling point detection device 3 is disposed approximately in the center of this heater 2. A heating container 4 is placed on the heater 2 and has an outer bottom in contact with the heater 2, and the heating container 4 is heated by the heater 2. Further, the boiling point detection device 3 is in contact with the outer bottom of the heating container 4, and this boiling point detection device 3 has a temperature sensing element 5,
In addition, the inner tube 7 is inserted into the outer tube 6 which has a cylindrical shape with a bottom so as to be vertically movable. Reference numeral 8 denotes a tray placed so as to cover the upper opening of the inner cylinder 7, and the temperature sensing element 5 is fixed on the tray 8 via an insulating plate 9. Reference numeral 10 denotes a heat receiving plate, which covers the upper opening of the receiving tray 8 and is in contact with the temperature sensing element 5 via an insulating plate 11. Further, the heat receiving plate 10
is in contact with the outer bottom of the heating container 4. Reference numeral 12 denotes a heater for heating the temperature sensing element provided at the upper part of the inner circumferential wall of the inner cylinder 7. A spring 13 is interposed between the outer cylinder 6 and the inner cylinder 7, and this spring 13 always urges the inner cylinder 7 upward.

In the above configuration, when the heating container 4 is placed on the heater 2, the heat receiving plate 10 comes into pressure contact with the outer bottom of the heating container 4. In this state, electricity is started to be applied to the heater 2, and at the same time, electricity is also applied to the heater 12 for heating the temperature sensing element for a certain period of time to heat the temperature sensing element 5. This results in
Since the temperature detected by the temperature sensing element 5 increases quickly, the fourth
As shown in the figure, it is possible to correct the delay in the temperature rise detected by the temperature sensing element 5 when the amount of water in the heating container 4 is small or when the heating container 4 with poor thermal conductivity is used. This allows the boiling point to be detected accurately. Note that if the amount of water is large, it will take time for the water to boil. That is,
Since the temperature of the water gradually rises, even if the temperature sensing element heating heater 12 is energized for a certain period of time to heat the temperature sensing element 5, the boiling point detection device 3 temporarily detects a relatively high temperature. After that, the temperature follows the temperature of the water in the heating container 4, so there is almost no effect. Therefore, the boiling point of water can be detected with high accuracy by energizing the heater 12 for heating the temperature sensing element for a certain period of time, and after the energization ends, detecting the temperature at the bottom of the heating container 4 with the boiling point detection device 3. It is.

In the above embodiment, the heater 2 has been described as a sheathed heater, but the present invention is not particularly limited to the type of heater, and the heating container 4 may be heated by burning gas or the like. It is a good thing.

As is clear from the description of the above embodiments, according to the present invention, a temperature sensing element is provided in the inner cylinder of the boiling point detection device for heating the temperature sensing element for a certain period of time after heating by the heating means for heating the heating container is started. Since a heating heater is provided, the boiling point of any heating container can be detected with high accuracy regardless of the amount of water, eliminating over-boiling or under-boiling of water. Furthermore, since this boiling point detection device has a simple structure, it can be provided at low cost.

[Brief explanation of drawings]

FIG. 1 is a vertical sectional view of a conventional stove with a boiling point detection device, FIG. 2 is a temperature detection characteristic diagram of the same stove, and FIG. 3 is a vertical sectional view of a stove with a boiling point detection device showing an embodiment of the present invention. FIG. 4 is a temperature detection characteristic diagram of the stove. 3... Boiling point detection device, 4... Heating container, 5...
Temperature sensing element, 6... Outer tube, 7... Inner tube, 8... Receiver, 9... Insulating plate, 10... Heat receiving plate, 11... Insulating plate, 12... Heater for heating the temperature sensitive element.

Claims (1)

[Claims] 1. A heating device that contacts the outer bottom of the heating container and heats the heating container, and a boiling point detection device that is arranged approximately in the center of the heating device and contacts the outer bottom of the heating container, The device includes an outer cylinder,
an inner cylinder inserted into the outer cylinder so as to be vertically movable; a saucer placed so as to cover the upper opening of the inner cylinder;
A temperature sensing element fixed on the tray via an insulating plate, and a heat receiving plate that covers the upper opening of the tray and contacts the temperature sensing element via the insulating plate, and also contacts the outer bottom of the heating container. Consisting of
A stove with a boiling point detection device, further comprising a heater for heating the temperature sensing element for a certain period of time after heating by the heating means is started, in an inner cylinder of the boiling point detection device.