JPH0322164B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION <Technical Field> The present invention relates to a liquid heating container, and more particularly, to a liquid heating container having a dry cooking prevention function and a water draining function from a pouring pipe.

<Prior art> Conventionally, a middle container was provided inside the outer case, and a heating element was provided at the bottom of the middle container to boil the water inside the middle container or to keep it at a high temperature. , so-called electric pots are known as liquid heating containers.

In this electric pot, since the heating element is provided while being immersed in water or boiling water, the watertight structure becomes complicated in consideration of electrical insulation, and there is a tendency for the pot to become large.

Therefore, although it is known that a heating element is provided outside the inner container, since indirect heating is used, there are some problems in terms of thermal efficiency compared to direct heating.

Taking these points into consideration, the patent applicant in question:
We filed a patent application for a liquid heating container with a ceramic heater integrated with the spouting pipe, but we installed a pumping hole to prevent dry cooking by the ceramic heater, and the lower end of the spouting pipe was left wide open. It was hot. Therefore, when the internal pressure of the medium container is increased by operating the bellows type air pump, the liquid may be taken out through the lower end opening of the spout pipe, and the liquid level may become lower than the pumping hole, resulting in an empty state. . On the other hand, in order to solve this problem, it is possible to block the lower end of the spout pipe, but in this case, when the spout pipe is removed, liquid remains inside the spout pipe, and this residual It takes time and effort to remove the liquid.

<Purpose> The present invention improves heating efficiency by installing a ceramic heater in a pouring pipe, providing a drainage hole in a position above the ceramic heater in the pouring pipe, and providing a drainage hole in the pouring pipe with a smaller diameter than the pumping hole. The purpose of the present invention is to provide a bottom wall having a diameter of 100 mm to keep the water level above a ceramic heater at all times, effectively prevent dry cooking, and easily drain the liquid in the spouting pipe.

<Structure> In order to achieve the above object, the liquid heating container of the present invention has an inner container inside an outer case and a pouring pipe inside the inner container, and includes a ceramic heater for heating the liquid. is provided in the spouting pipe, and a pumping hole is provided in the spouting pipe at a position above the ceramic heater.Furthermore, a bottom wall is provided in the spouting pipe, and a drain hole with a smaller diameter than the pumping hole is provided in the bottom wall. It is characterized by

<Examples> Hereinafter, examples will be described in detail with reference to the accompanying drawings showing examples.

FIG. 1 is a longitudinal sectional side view showing an embodiment of an electric pot as a liquid heating container.

1 is the outer case of the electric pot, 2 is the middle container made up of a double vacuum bottle, 3 is the pouring pipe inserted into the middle container 2, and 4 is connected to the pouring pipe 3. 5 is a ceramic heater, and 6 is a lid unit provided on the upper part of the outer case 1 so as to be openable and closable. Also, 16
is means for maintaining the switching element in a state in which the ceramic heater is cut off.

To explain in more detail, the outer case 1 is formed into a cylindrical shape with a predetermined diameter, and a support 11 for supporting the inner container 2 is fitted into the lower end opening in a locking manner, and the support 11 is attached to a seat. It is rotatably supported on 12. In addition, 13 is a socket for connecting to a power line, 14 is a magnetic plug, and 15 is fitted into the upper end opening of the cylindrical body to keep the upper end opening of the double vacuum bottle 2 immovable. It is a supporting lower mouth member.

The discharge pipe 4 passes through a predetermined position of the lower mouth member 15, and has one end facing the central opening of the lower mouth member 15 and the other end facing the outside of the lower mouth member 15. However, for the part facing the central opening, a downwardly curved pipe 41 is provided, and a connecting pipe 43 that communicates the discharge pipe 4 and the downwardly curved pipe 41 is provided.
By providing this, the pouring pipe 3 can be easily attached.

The pouring pipe 3 is a cylindrical body made of ceramic, and its upper end is fitted into a downwardly curved pipe 41, and its lower end is positioned slightly above the inner bottom surface of the double vacuum bottle 2. .

Then, as shown in FIG. 2, at the lower end of the pouring pipe 3, a temperature sensing element 53 as a sensor is formed by integrally sintering a temperature sensing resistor 52 between the ceramic layer 51. A ceramic heater 5 is formed above the ceramic heater 5 by integrally sintering a resistor 54 between the ceramic layers 51, and a pumping hole 32 penetrating the side wall of the spout pipe 3 is formed slightly above the ceramic heater 5.
has been established. In addition, a bottom wall is provided in the pouring pipe 3, a drain hole 33 is provided in this bottom wall, and a drain hole 33 is provided in the bottom wall.
3 is a predetermined diameter that is smaller than the pumping hole 32 and not so small as to interfere with the draining operation.

Incidentally, 56 and 57 are lead wires buried in the side wall of the pouring pipe 3 at equal intervals, and the lead wire 56
A lead wire 57 electrically connects the socket 13 and the ceramic heater 5, and a lead wire 57 electrically connects the temperature sensing element 53 to a control circuit to be described later.

Each lead wire 5
6 and 57 are brought close to each other and pulled out from approximately one place, the pulled out lead wires are covered with silicone rubber, for example, and the lead wires 56 and 57 and the pouring pipe 3 are integrated with a waterproof band 39 made of rubber or the like. It is completely waterproofed by holding it in place.

The lid unit 6 includes a stopper 61 that closes the upper end opening of the vacuum double bottle 2, and a bellows type air pump 62.
and a lock lever 63, and is connected to the lower opening member 15 at its rear end (on the right side in FIG. 1) so as to be vertically movable.

Note that 64 and 65 are presser lids, the presser lid 64 is located at the center opening of the presser lid 65, and the spring 66
By being pushed up by the bellows type air pump 62, the upper end opening of the bellows type air pump 62 is opened, thereby preventing abnormal pressure increase in the vacuum double bottle 2.

FIG. 3 is an electrical circuit diagram of an electric pot, in which the output terminal of a comparator 74 is supplied with a reference voltage by fixed resistors 71 and 72, and a comparison voltage is supplied by a fixed resistor 73 and a temperature sensing element 53. A reset switch 75 and a relay coil 77 are connected in series. Then, a normally closed terminal 78 driven by the relay coil 77 is connected in series with the temperature sensing element 53,
Another normally closed terminal 79 is connected in series with the ceramic heater 5, and a normally open terminal 80, an alarm element 81 such as a buzzer, and a reset switch 76 are connected in series.
The temperature sensing element 53 has a positive resistance-temperature characteristic, and the reset switches 75 and 76 are normally closed switches that operate in conjunction with each other.

The operation of the electric pot having the above configuration is as follows.

If the lid unit 6 is opened and water is poured into the vacuum double bottle 2, then the magnetic plug 14 is inserted into the socket 13, then the ceramic heater 5 is energized to heat and raise the temperature of the water. Therefore, after the ceramic heater 5 is energized for a predetermined period of time, the bellows type air pump 62 is activated by pressing down the presser cover 64 together with the presser cover 65, thereby discharging the hot water in the vacuum double bottle 2. It is an easy-to-use electric pot that can be taken out to the outside through the pouring pipe 3 and the discharge pipe 4.

In this case, the bellows type air pump 6
2 to raise the internal pressure of the vacuum double bottle 2, most of the hot water in the vacuum double bottle 2 is taken out from the pumping hole 32 through the pouring pipe 3 and the discharge pipe 4.

When the hot water is taken out, the amount of hot water inside the vacuum double bottle 2 decreases, but if the drawing hole 32 of the spout pipe 3 is exposed above the hot water level, the bellows type air pump 62 The internal pressure increase inside the vacuum double bottle 2 is released into the atmosphere from the pumping hole 32 through the pouring pipe 3 and the discharge pipe 4.
The hot water level does not drop any further, and the ceramic heater 5 is kept immersed in the hot water to prevent dry cooking.
1. Abnormal temperature rise of the plug body 61 etc. can be prevented.

In addition, when the spouting pipe 3 is taken out or all the water in the vacuum double bottle 2 is discarded, the water in the spouting pipe 3 is automatically drained from the drain hole 33. This eliminates the need for special work, and reliably prevents the inconvenience of old water remaining in the spouting pipe 3 forever.

The above is normal operation, and empty cooking can be reliably prevented.

If the ceramic heater 5 is energized without any water being put into the vacuum double bottle 2, it will be in an empty state and the temperature detected by the thermosensor 53 will rise abnormally.

Therefore, the comparator 74 energizes the relay coil 77 to cut off the energization to the ceramic heater 5, and energizes the alarm element 81 to notify the abnormal state.

However, in this case, since the normally closed terminal 78 is turned OFF by energizing the relay coil 77,
Even if the temperature detected by the temperature sensing element 53 decreases, the relay coil 77 continues to be energized, and the ceramic heater 5 is maintained in the energized state.

Further, in order to release the current cut-off state of the ceramic heater 5, the reset switch 75 may be temporarily turned off. In this case, if you operate the reset switch 75 while forgetting to add water, it will be in a dry cooking state, so the power to the ceramic heater 5 is cut off in the same way as above, and
Alarm element 81 can be activated.

According to the above embodiment, the temperature sensing element 53 located below the ceramic heater 5 can reliably detect the dry cooking state and prevent the dry cooking.
Moreover, once the dry heating state is detected, the ceramic heater 5 can be kept in the energized state unless the reset switch is operated.

FIG. 4 is an electric circuit diagram showing another embodiment,
Zero volt switch 83 by resistors 71 and 72
A reference voltage is applied to the non-inverting input terminal 4 of the (Kyocera Corporation μPC1701C), and a comparison voltage is applied to the inverting input terminal 3 of the zero-volt switch 83 through the temperature sensing element 53 and the resistor 73, and the pulse output terminal of the zero-volt switch 83 is applied. The pulse signal from 6 is applied to the gate terminal of triac 82, and ceramic heater 5 is connected in series with triac 82. Then, connect the comparator output terminal 2 to the resistor 7
It is connected to connection points 1,72.

Therefore, according to this embodiment as well, it is possible to detect the dry cooking state, prevent the dry cooking state, and maintain the state in which the power supply to the ceramic heater 5 is cut off after the dry cooking state is detected.

FIGS. 5 to 8 are central vertical sectional views showing other embodiments of the pouring pipe, in which a ceramic pipe is connected to the lower end of the stainless steel pipe.

More specifically, in the embodiment shown in FIG. 5, the ceramic pipe 34 and the stainless steel pipe 35 have approximately the same diameter and are integrally connected, and a sensor as a temperature sensor is attached to the lower end of the side wall of the pipe 34. While forming the thermal element 53,
A ceramic heater 5 is installed slightly above the temperature sensing element 53.
Further, a drainage hole 32 is provided at the lower end of the side wall of the stainless steel pipe 35, and a drain hole 33 having a smaller diameter than the drainage hole 32 is provided at the center of the bottom wall 38 provided in the ceramic pipe 34.

In FIG. 6, a ceramic pipe 34 is shown.
is formed to be smaller in diameter than the stainless steel pipe 35 and smaller than the pumping hole 32, and the ceramic heater 5 and temperature sensing element 53 are formed in this small diameter portion, and the upper end of the pipe 34 is connected to the large diameter connecting portion 3.
6, and the opening at the lower end of the pipe 34 serves as a drain hole 33.

In FIG. 7, a ceramic pipe 34 is shown.
A flange 37 extending outward and inward is formed at the lower end of the flange 37, and a drain hole 33 is formed in the center of the flange 37.
Further, a ceramic heater 5 is formed near the center of the flange 37, and a temperature sensing element 53 is formed near the outer periphery of the flange 37.

In addition, in the embodiments shown in FIGS. 6 and 7, as in the embodiment shown in FIG. Even when the pumping hole 32 is located above the water surface, the connection between the stainless steel pipe 35 and the ceramic pipe 34 and the pipe 34 will not abnormally rise in temperature while being in water or hot water, and both pipes 34 , 35 may come off due to the difference in coefficient of thermal expansion.

In FIG. 8, a pumping hole 32 is provided in a ceramic pipe 34, and a pumping hole 32 is provided at the lower end of the pipe 34.
The only difference from the embodiment shown in FIG. 5 is that a stainless steel bottom wall 38 having a drain hole 33 having a diameter smaller than that of the pumping hole 32 is provided, and the other configurations are the same.

Therefore, in this case, when the pumping hole 32 is located above the water surface, the connecting portion of both pipes 34 and 35 will be located above the water surface, but since the ceramic heater 5 is located underwater or in hot water, , there is almost no risk of abnormal temperature rise at the connection part.

As is clear from the above explanation, the pouring pipe 3
Even in the case where the spouting pipe 3 is composed of a stainless steel pipe 35 and a ceramic pipe 34, heating, temperature rise, prevention of dry cooking, and spouting pipe 3 are performed in the same manner as in the above embodiment in which the spouting pipe 3 is composed only of a ceramic pipe. It is possible to achieve water removal etc.

In the above embodiment, the ceramic heater and the dry cooking prevention sensor are integrally formed with the spout pipe, but it is also possible to form only the ceramic heater integrally with the spout pipe and omit the dry cooking prevention sensor. In this case as well, since the pumping hole is located above the ceramic heater, the ceramic heater is always immersed in hot water, and there is little risk of it running dry.

Further, instead of the dry cooking prevention sensor, or by integrally forming a temperature control sensor with the dry cooking sensor, the temperature of the water inside the inner container can be maintained at a predetermined temperature.

Incidentally, the liquid heating container of the present invention is not limited to the above-mentioned embodiments; for example, it is also possible to make the pouring pipe integrally formed with the ceramic heater removable together with the discharge pipe.
It goes without saying that a metal inner container can be used in place of the vacuum double bottle, and that various other design changes can be made without departing from the gist of the invention.

<Effects> As described above, in the liquid heating container of the present invention, since the ceramic heater for heating the liquid is provided in the pouring pipe, the liquid can be directly heated by the ceramic heater, and the heating efficiency can be improved. A pumping hole is provided above the ceramic heater in the spouting pipe, and a bottom wall with a drainage hole smaller in diameter than the pumping hole is provided in the spouting pipe. By releasing all the internal pressure rise in the container from the pumping hole to the atmosphere through the pouring pipe and the discharge pipe, and preventing the liquid level from falling, the ceramic heater is always kept immersed in the liquid, making dry heating effective. The unique feature of this system is that it can prevent this problem and automatically drain the liquid inside the spouting pipe when the spouting pipe is removed, eliminating the need for special work to remove the liquid and making it easier to use. be effective.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional side view showing an embodiment of the liquid heating container of the present invention, FIG. 2 is a partially cutaway perspective view of the pouring pipe 3, and FIG. 3 is an electric circuit diagram of the liquid heating container.
FIG. 4 is an electric circuit diagram showing another embodiment, and FIGS.
FIG. 8 is a longitudinal sectional side view of the main part showing another embodiment of the pouring pipe 3. 1... External case, 2... Vacuum double bottle as a medium container, 3... Pour pipe, 5... Ceramic heater, 3
2...Sumpling hole, 33...Drain hole.

Claims (1)

[Scope of Claims] 1. In a liquid heating container having an inner container inside an outer case and a spouting pipe inside the inner container, a ceramic heater for heating the liquid is provided in the spouting pipe, and the spouting pipe is provided with a ceramic heater for heating the liquid. A liquid heating container characterized in that a pumping hole is provided at a position above a ceramic heater, a bottom wall is provided in the pouring pipe, and a drain hole having a smaller diameter than the pumping hole is formed in the bottom wall. 2. The liquid heating container according to claim 1, wherein the entire pouring pipe is made of ceramic pipe. 3. The liquid heating container according to claim 1, wherein the upper part of the pouring pipe is made of a stainless steel pipe, and the remaining part is made of a ceramic pipe. 4. The liquid heating container according to claim 3, wherein the pumping hole is provided in the stainless steel pipe. 5. The liquid heating container according to claim 3, wherein the pumping hole is provided in a ceramic pipe.