JPH041611B2 - - Google Patents

Description

[Detailed description of the invention] <Technical field> TECHNICAL FIELD This invention relates to liquid heating containers.

<Prior art> Conventionally, an inner container was provided inside the outer case, and a heating element was further provided at the bottom of the inner container so that the hot water inside the inner container could be boiled or kept at a high temperature. A so-called electric pot is known as a liquid heating container.

In such electric pots, since the heating element is provided while being immersed in water or hot 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 attached to the outside of the inner container, since it is indirect heating, there are some problems in terms of thermal efficiency compared to direct heating.

Considering these points, it is conceivable to install a ceramic heater integrally with the pouring pipe, but
By simply having a heating function, there are problems such as not being able to detect the temperature of the liquid and detect abnormal temperature rises such as the temperature rising above the set temperature or dry cooking to control the power supply to the ceramic heater. had.

<Purpose> The present invention simplifies the watertight structure by integrally forming a heating element with a ceramic pouring pipe, thereby achieving miniaturization, and has excellent electrical insulation and heat resistance. As a result, the heating element can be installed inside the inner container, improving heating efficiency. Furthermore, by forming the temperature sensor integrally with the ceramic pouring pipe, the liquid temperature sensing performance is improved. The purpose is to effectively achieve temperature control and also to simplify the configuration.

<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 spouting pipe inside the inner container, and the spouting pipe is made of ceramic. It is characterized in that a heater and a temperature sensor are embedded integrally at the pipe position forming the pouring passage of the pouring pipe. The temperature sensor may be one that detects abnormal temperature rise inside the medium container.
It includes a temperature control sensor that detects an abnormal rise in water temperature above a set temperature, or a dry cooking prevention sensor that detects an abnormal rise in temperature above the boiling point.

<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. 6 is a discharge pipe, 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.

To explain in more detail, the outer case 1 is formed into a cylindrical shape with a predetermined diameter, and the support body 11 is fitted into the inner container 2 at the lower end opening in a locking manner, and the support body 11 is placed on the seat plate 12. is rotatably supported. In addition, 13 is a socket for connecting to a power line, 14 is a magnetic plug,
Reference numeral 15 denotes a lower opening member that is fitted into the upper opening of the cylindrical body and immovably supports the upper opening of the double vacuum bottle 2.

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 so that the pouring pipe 3 can be easily attached. ing.

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

As shown in FIG. 2, a temperature-sensitive resistor 52 is integrally sintered between the ceramic layers 51 in the shape of a sandwich at the lower end of the pouring pipe 3, so that a dry cooking prevention sensor 53 is used as a temperature sensor.
is integrally buried in the position of the pipe forming the pouring passage of the pouring pipe 3, and a resistor 5 is placed between the ceramic layer 51 above the dry cooking prevention sensor 53.
A ceramic heater 5 is integrally buried and formed in the position of the pipe forming the pouring passage of the pouring pipe 3 by integrally sintering the ceramic heater 5 in the shape of a sandwich trench.
Further, above the ceramic heater 5, a temperature-sensitive resistor 55 is integrally sintered between the ceramic layers 51 in a sandwich-like shape, thereby forming a temperature control sensor 50 as a temperature sensor and a pouring passage for the pouring pipe 3. It is buried and formed integrally at the location of the pipe.

Note that 56 is a lead wire covered with silicone rubber and having one end sintered to the outer surface of the pouring pipe 3, and the pair of lead wires 56 electrically connects the socket 13 and the ceramic heater 5. The dry cooking prevention sensor 53 is connected to the other pair of lead wires 56.
and an electric circuit to be described later, and the temperature control sensor 50 is connected by the remaining pair of lead wires 56.
and the above-mentioned electric circuit are electrically connected. Further, 31 is a waterproof band made of rubber or the like that holds the upper part of the pouring pipe 3 and the lead wire 56.

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, which 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 temperature rise inside 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 has a surplus voltage for comparison by a fixed resistor 73 and a temperature control sensor 50. A relay coil 75 is connected to the relay coil 75, and the ceramic heater 5 is connected in series with a normally closed terminal 76 driven by the relay coil 75. In addition, the dry cooking prevention sensor 53
A relay coil 79 is connected to the collector terminal of a switching transistor 78 to which a base bias is applied by a fixed resistor 77. and,
Normally closed terminal 80 driven by relay coil 79
is connected in series with the fixed resistor 71, and the normally closed terminal 81
is connected in series with the dry cooking prevention sensor 53, the normally open terminal 82 is connected in series with an alarm element 83 such as a buzzer, and a normally open reset switch 8.
4 is connected in parallel with the normally closed terminal 81 and operates in conjunction with the reset switch 84.
is connected in series with the normally open terminal 82.

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

By opening the lid unit 6 and pouring water into the vacuum double bottle 2, and then inserting the magnetic plug 14 into the socket 13, the ceramic heater 5 is energized to heat and raise the temperature of the water. here,
Since the ceramic heater 5 heats directly in hot water, it has good heating efficiency.Furthermore, since the heater is formed integrally with the ceramic pipe that constitutes the pouring pipe 3, it can be protected from the outside and is insulated. It is possible to maintain good thermal conductivity while maintaining good electrical insulation and heat resistance, thereby increasing safety and improving heating efficiency. When the temperature of the hot water inside the double vacuum bottle 2 reaches a predetermined temperature, the relay coil 75 is energized to turn off the normally closed terminal 76, cutting off the power to the ceramic heater 5 and allowing the temperature of the hot water to drop. By restarting the power supply to the ceramic heater 5, the hot water inside the vacuum double bottle 2 can be maintained at a predetermined temperature close to the boiling point. Therefore, by pushing down the presser cover 64 together with the presser cover 65, the bellows type air pump 62 is activated, and thereby the hot water in the vacuum double bottle 2 is discharged to the outside through the pouring pipe 3 and the discharge pipe 4. It can be taken out.

If most of the hot water inside the vacuum double bottle 2 is removed, or if the ceramic heater 5 is energized while the water is forgotten to be put into the vacuum double bottle 2, it will become empty and the internal temperature will become abnormal. rise (100
℃), the dry cooking prevention sensor 53 turns on the switching transistor 78, and the relay coil 79 turns on the normally closed terminal 80.
Since it is turned OFF, electricity can be prevented from being applied to the ceramic heater 5, and the dry heating state can be resolved. Here, both the temperature control sensor 50 and the dry cooking prevention sensor 53 are integrally formed with the ceramic pouring pipe 3, so they have excellent electrical insulation, heat resistance, and thermal conductivity. Since both the sensors 50 and 53 are embedded in the spouting pipe 3 at the pipe position forming the spouting passage, together with the excellent thermal conductivity, temperature sensing can be performed well. , it is possible to improve the hot water temperature sensing performance. Further, since both the sensors 50, 53 and the ceramic heater 5 are embedded and formed integrally in the pouring pipe 3, the pouring pipe 3 also serves as a mounting means for both the sensors 50, 53 and the ceramic heater 5. This means that there is no need for special mounting means, the mounting structure is simplified, and the size is reduced.
Weight reduction can be achieved. In addition, since the relay coil 79 maintains the energized state, even if the internal temperature drops, the energization to the ceramic heater 5 is maintained in the stopped state, and the dry heating prevention state can be canceled only when the reset switch 84 is operated. . However, if the reset switch 84 is operated without adding water, the dry cooking state will return, so the above operation can be repeated to prevent dry cooking. Also, in the dry cooking prevention state, the alarm element 83 is energized to notify that there was a dry cooking state, that is, the ceramic heater 5 was energized even though the amount of hot water was small. According to the embodiment described above, since the temperature control sensor 50 is located above the ceramic heater 5, the power supply to the ceramic heater 5 is controlled by the temperature control sensor 50 while hot water can be taken out. To be able to maintain the temperature of hot water at a predetermined temperature close to the boiling point, and to ensure that after hot water cannot be taken out, the dry cooking state is detected by the dry cooking prevention sensor 53 and the dry cooking is prevented. Furthermore, once the dry heating state is detected, the ceramic heater 5 can be kept in the energized state unless the reset switch 84 is operated.

FIG. 4 is an electric circuit diagram showing another embodiment,
The only difference from FIG. 3 is that a normally closed reset switch 84 is connected in series with a relay coil 79, and that the series connection circuit of a relay contact 82, an alarm element 83, and a reset switch 85 is omitted.

Therefore, according to this embodiment, the temperature control sensor 50 controls the amount of electricity supplied to the ceramic heater 5, prevents dry cooking, and controls the dry heating in the same way as the embodiment shown in FIG. 2, except that no notification is given. It is possible to detect the cooking state, prevent dry cooking, and maintain the dry cooking prevention state.

In the above embodiment, only the example in which the temperature control sensor is integrally formed above the ceramic heater of the pouring pipe and the dry cooking prevention sensor is integrally formed below is explained, but the dry cooking prevention sensor is omitted. In this case, dry cooking cannot be prevented, but there is no particular disadvantage because temperature control can be performed to prevent the liquid temperature from rising above the set temperature. In addition, the liquid heating container is not limited to the electric pot described in the example, but can also be formed by forming the dispensing pipe of a conventionally known thermos flask from ceramic, and integrally sintering a heater and a temperature control sensor at a predetermined position. In addition, various design changes can be made without changing the gist of the invention.

<Effects> As described above, the liquid heating container of the present invention has an inner container inside the outer case and a pouring pipe inside the inner container, in which the pouring pipe is made of ceramic. The feature is that a heater and a temperature sensor are integrally buried in the pipe position that forms the pouring passage of the pouring pipe, and by integrally forming the heater and temperature sensor with the ceramic pouring pipe, it is possible to prevent leakage from the outside. Because it protects and insulates, it has electrical insulation, heat resistance,
It maintains good thermal conductivity, making it possible to simplify and downsize the watertight structure without requiring a special watertight structure, and improve heating efficiency by constantly immersing the ceramic heater in liquid and heating it directly. In addition, since the temperature sensor is always immersed in the liquid, together with the provision of the temperature sensor at the pipe position forming the pouring passage, the temperature sensing performance can be improved. Since the pouring pipe also serves as a mounting means for the heater and temperature sensor, no special mounting means are required.
This has the unique effect of simplifying the mounting configuration and achieving reduction in size and weight.

[Brief explanation of drawings]

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. 1... Exterior case, 2... Vacuum double bottle as a medium container, 3... Pour pipe, 5... Ceramic heater, 5
0...Temperature control sensor.

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, the spouting pipe is formed of ceramic, and the spouting passage of the spouting pipe is formed of ceramic. A liquid heating container characterized in that a heater and a temperature sensor are embedded integrally at the position of a pipe to be formed. 2. The liquid heating device according to claim 1, wherein the temperature sensor is a dry cooking prevention sensor and/or a temperature control sensor. 3. The liquid heating device according to claim 1, wherein a temperature sensor is provided below the ceramic heater forming position of the pouring pipe.