JPS6219132A - Electric pot - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION (Field of Industrial Application) The present invention relates to an electric water heater equipped with a metal vacuum container for heating beverages and the like.

(Prior art) Conventionally, this type of electric water heater
As proposed in Publication No. 32, a metal-controlled heater penetrating the vacuum layer of a vacuum container is provided to heat the beverage, as is proposed in Publication No. 59-101932 and Japanese Patent Application Publication No. 59-108518. As proposed in the publication, a heater is provided on the outer surface of the inner container within the vacuum layer, and heat from a heating element is conducted to the inner container via an electrical insulator to heat the beverage in the inner container.

(Problem to be solved by the invention) However, in the former case, since the heater is installed at a position away from the inner bottom of the inner container, it may become dry-burned when the amount of beverage is small, or the heater may become overheated. Due to the high surface power density, boiling noise and vibrations may occur when heating beverages.

In addition, in the latter case, there is a large thermal resistance in the transmission from the heating element to the beverage, which causes the heating element to reach a high temperature and generate outgas, reducing the vacuum life and increasing radiant heat loss, causing the vacuum container to become damaged. In addition, heat loss increases because the lead wires of the heater are led out from the vacuum sealing part. On the other hand, there is a heating method using an excitation coil, but it is possible that pressure is applied to both the inner and outer containers through the vacuum space, causing deformation.In order to maintain strength against pressure, the inner container needs to be made thicker. 3P has drawbacks such as a reduction in heating efficiency by the excitation coil.

(Means for Solving the Problems) The present invention has been made in order to eliminate the above-mentioned drawbacks,
To obtain an electric water heater that can heat even a small amount of beverage, prevents boiling noise and vibration, maintains the strength of the inner container and outer container, and has a long vacuum life. For this purpose, the bottom member of the outer container is formed to have an outwardly convex shape, and an excitation coil is provided on the outer surface of the bottom member of the outer container made of a non-magnetic material, and the bottom member is made of a magnetic material that is heated via the excitation coil. The bottom member of the inner container is formed in a convex shape along the bottom member of the outer container.

(Function) By doing this, the strength is maintained against the pressure applied to the inner and outer containers, the inner container is efficiently heated by the excitation coil, and even a small amount of beverage can be heated efficiently, compared to the conventional container. This also eliminates the occurrence of outgas.

(Example) An embodiment of the present invention will be described below with reference to the drawings.

The structure of the embodiment is as shown in FIGS. 1, 2, 6, and 4. Reference numeral 1 denotes a vacuum container consisting of an inner container 101 having a spout 104 for water injection, and an outer container 102. Both containers 1
A sealed space 103 is formed between 01 and 102. The inner container 101 is made of a magnetic stainless steel plate, and is airtightly integrated with a bottom member 105 made of the same material that forms the bottom surface and formed to have an outwardly convex shape at a joint 113 by welding the entire circumference or the like. The outer container 102 is made of a non-magnetic stainless steel plate, and a bottom member 106 is made of the same material as the bottom and formed in a convex shape along the bottom member 105.
and a joint part 112, which are airtightly integrated by welding the entire circumference or the like. Reference numeral 107 denotes a recess, which has an elongated cylindrical shape and is provided in the center of the bottom member 106, and a bottomed pipe 108 made of non-magnetic stainless steel connects the opening 111 to the bottom member 1.
The bottom part of the bottomed pipe 108 is connected to the bottom member 105 at the joint 1 by welding or the like at the joint 110 of 06.
In 2009, they were joined by welding or the like so that they became one piece P in terms of heat transfer. The inner container 101 has a mouth portion 10
4 is airtightly fixed to the outer container 102 at the upper end, and the bottom member 105
A space 10 is fixed at the center of the outer bottom of the container by a bottomed pipe 108 and is formed between the containers 101 and 102.
3 is in a vacuum state. 2 is the bottom body.

It is a cylindrical piece with a bottom fixed to the lower part of the vacuum container 1,
Legs 201 are provided on the outer bottom surface for installation on a tabletop ring. The filter is a handle and is provided with a button 602 for rotating the stopper filter 01 on a fulcrum 303, which is attached to the upper part and the rear side of the vacuum container 1 to open and close the first mouth part 104, and a power plug 305 is attached to the lower side. A plug receiving portion 304 is provided for connection via a magnet. Reference numeral 7 denotes an electric circuit component provided at the inner bottom of the bottom body 2. 5 is the excitation coil.

It is provided in a spiral shape on the outer bottom surface of the bottom member 106 to generate a high-frequency magnetic field, which will be described later, and heats the bottom member 105 by generating an eddy current in the bottom member 105.

Reference numeral 701 is a rectifier circuit that converts the commercial power supply through the plug receiver 304 into DC, and the converted DC is converted into high-frequency current P through the inverter circuit 702. A control circuit 703 inputs a control signal to the inverter circuit 702 via a driver circuit 704, converts the DC current from the inverter circuit 702 into a high-frequency current of a predetermined frequency, and energizes the excitation coil 5 to generate a high-frequency magnetic field. It is the basis. Reference numeral 6 denotes a temperature detection element, which is composed of a thermistor and is provided deep inside the bottomed pipe 108, detects the temperature of the water 4 in the inner container 101 via the bottom member 105, and outputs an electric signal according to this temperature. It is something to do. This electrical signal is transmitted to the temperature detection circuit 705.
For example, the control circuit 7
This is to change the output pulse width of 03. In addition.

Rectifier circuit 701. Inverter circuit 702. Control circuit 70
reactor.

Driver circuit 704. The temperature detection circuit 705 is provided inside the electric circuit component 7. 710 and 711 are a comparator and a variable resistor for setting the reference voltage, respectively.

A control circuit 70 is housed in the filter, and as shown in FIG. 4, a variable resistor 711 and a temperature detection element 6 are connected to the input terminals of a comparator 710, respectively, so that when the temperature of the water 4 rises, the temperature is detected. When the output signal of the circuit B exceeds the reference voltage set by the variable resistor 7117P, a signal corresponding to this deviation is output from the comparator 710 and is given to the control circuit 70P. .

The operation of this embodiment having the above configuration will be explained.

Fill the vacuum container 1 with water from the mouth 104 and plug the power plug 30
5 to the plug receiving part 304. Inverter circuit 70
A high frequency current flows from 2 to the excitation coil 5, and the high frequency magnetic field generated from the excitation coil 5 causes the bottom member 105 to generate heat, heating the water 4 and raising its temperature.

At this time, the bottom member 105 generates heat because it is made of magnetic stainless steel material, and the bottom member 106 does not generate heat because it is made of non-magnetic stainless steel material. At this time, in order to reduce heat loss, both the inner containers 101 and 102 are preferably made thick.

If the thickness of the bottom portion 105 has a large resistance, eddy current loss will occur.

Since it is larger, the thinner the material, the more heat can be obtained with the same magnetic field. Furthermore, since the distance A between the two bottom members 105 and 106 is made as small as possible, and the excitation coil 5 is also configured to be in close contact with the bottom member 106, the coupling coefficient between the primary inductance of the excitation coil 5 and the secondary inductance due to the bottom member 105 is reduced. is brought close to 1 to efficiently heat the bottom member 105. In addition, the inner container 101 is supported at two locations above and below the joint 109 between the mouth portion 104 and the axis of the excitation coil 5 to provide mechanical strength and vibration resistance due to the electromagnetic force generated by the high frequency magnetic field of the excitation coil 5. To heat water 4 efficiently and without changing over time. That is, the water 4 in the inner container 101
Since the water is heated by the entire surface of the bottom member 105, the surface area for heating the water 4 becomes large, and even at high wattages, heat is transferred by nucleate boiling, and no noise or vibration occurs during boiling. water 4
When the temperature of the water reaches, for example, a set value of 98° C., the temperature detection element 6 senses this and controls the current flowing to the excitation coil 5 so as to keep the rise in water temperature constant. At this time, the temperature detection element 6 is connected to the bottomed pipe 1 which is thermally connected to the bottom member 105.
08 to accurately detect the temperature of the water 4, and because the bottomed vibrator 108 has a small diameter and thin wall, the heat conduction resistance from the bottom member 105 to the bottom member 106 increases, resulting in heat loss due to heat release from the water. is small.

(Effects of the Invention) P According to the above nine inventions, the bottom member of the inner container made of a magnetic material and the bottom member of the outer container made of a non-magnetic material are each formed in a convex shape outward, thereby making it possible to form an inner container. It has a structure that can withstand high pressure, and by providing an excitation coil on the outer surface of the outer container bottom member, the generation of outgas is eliminated and the vacuum life is extended. When heating the water in the inner container, the bottom member of the inner container is efficiently heated, maintaining the strength of the 9-car container and preventing boiling noise and vibration.

It is possible to obtain an electric water heater that does not cause dry heating even when there is a small amount of beverage in the inner container.

[Brief explanation of the drawing]

゛Fig. 1 is a side sectional view of an electric water heater according to an embodiment of the present invention, Fig. 2 is a sectional view of the main part thereof, and Fig. 3 is an electric circuit diagram of the same.
FIG. 4 is an internal connection diagram of the main parts. 101... Inner container, 102... Outer container. 105, '106... Bottom member, 5... Excitation coil.

Claims (1)

[Claims] In an electric water heater that has a double structure of a metal inner container and an outer container, and the space formed between the inner and outer containers is a vacuum chamber, at least the bottom member (105) of the inner container (101)
) and at least the bottom member (106) of the outer container (102)
are made of magnetic material and non-magnetic material, respectively, and both bottom members (
105) and (106) are formed to have an outwardly convex shape, and an excitation coil (5) for heating the bottom member (105) is provided on the outer surface of the bottom member (106) of the outer container (102). An electric water heater featuring