JPS62290420A - 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 3. Detailed Description of the Invention Field of Industrial Application The present invention relates to an electric water heater for boiling water and keeping it warm in general households.

2. Description of the Related Art As shown in FIGS. 4 and 5, a conventional electric water heater of this type includes a cylindrical container 1 with a bottom, a heating element 2 for heating water contained in the container 1, and a heating element 2 for heating water contained in the container 1. , a first thermostat 3 attached to the bottom of the container 1 and connected in series with the heating element 2; and a first thermostat 3 attached near the heating element 2 and connected in series with the first thermostat 3. The second
a thermostat 4, an outer case 6 that covers the outer periphery of the container 1, and a lid 6 that covers the upper opening of the outer case 6;
It was composed of a water quantity display tube 7 communicating with the upper and lower parts of the container 1 and extending in the vertical direction. With this configuration, when there is water in the container 1, the temperature of the water is controlled by the first thermostand 3, while when there is no water in the container 1, the temperature of the water is controlled by the first thermostand 3, which is installed near the heating element 2. Generally, the second thermostat 4 would stop supplying electricity to the heating element 2 when the temperature reaches a high temperature. It has also been common to inform the user of the water level in the container 1 using the water level display tube 7. However, with this configuration, the user does not notice through the water level display tube 7 that there is no water in the container 1, and the heating element 2
When electricity is applied to the heating element 2, it is necessary to reach a temperature at which the second thermostat 4 installed near the heating element 2 operates. Moreover, the second thermostat 4 is normally set at an operating temperature that does not operate when water is present, and the operating temperature is quite high. Furthermore, even if the second thermostat 4 operates, there is no indication that there is no water, so the user does not notice it until he/she looks at the water quantity display tube 7.

Problems to be Solved by the Invention However, in such a conventional configuration, if the user mistakenly energizes the heating element 2 without filling the container 1 with water, the power is turned on until the user detects that there is no water, i.e. , since it takes time for the second thermostat 4 to operate, various parts become high temperature, causing the container 1 to discolor, and the components of the heating element 2 are required to be highly heat resistant. .

The present invention solves these problems by being able to detect that there is no water in the container and stop energizing the heating element, and also to notify the user that there is no water using sound or light. The object of the present invention is to provide an electric water heater that can notify the user.

Means for Solving the Problems In order to solve the above problems, the present invention provides a cylindrical container with a bottom, a heating element that heats the water contained in the container, and a temperature sensor that detects the temperature of the water. a detection means, a water level display tube that communicates with the inside of the container and extends in the vertical direction; a water level detection means that is provided adjacent to the water level display tube and outputs a signal depending on the presence or absence of water at the lower end; a boiling display element that indicates that the water is being boiled; a heat retention display element that indicates that the water is being kept warm; and a water supply alarm that indicates by sound or light that there is no water at the lower end of the water quantity display tube. and a control means which receives the outputs of the temperature detection means and the water level detection means and controls the energization of the heating element, the boiling display element, the heat retention display element, and the water supply alarm means.

Effects According to the above configuration, if there is no water in the container, the water level detection means quickly detects it, immediately stops the power supply to the heating element, and alerts the user that there is no water by sound or light. This system is safe and extremely easy to use.

Embodiment Hereinafter, one embodiment of the present invention will be described based on the accompanying drawings. In FIGS. 1 to 3, the same parts as those shown in FIG. 4 for the conventional example are given the same numbers, and the explanation thereof will be omitted.

FIG. 1 shows a circuit diagram of an electric water heater according to an embodiment of the present invention. Reference numeral 10 denotes temperature detection means, and this temperature detection means 1o includes a thermistor 11 pressed against the container 1, a resistor 12, and a resistor 12. /D converter 13. 2o
is a water level detection means, and this water level detection means 20 is an infrared LED mounted at opposite positions across a 7ft water display tube.
21, a phototransistor 22, a float 23 floating on water in the water quantity display tube 7, and resistors 24 and 25. 3o is a boiling LED (corresponding to a boiling display element) that indicates that water is being boiled; 40 is a heat retention LED (corresponding to a heat retention display element) that indicates that water is being kept warm; and 60 is a water supply notification means. , buzzer 61 and water supply L
It is composed of ED52. Reference numeral 6o denotes control means, which is comprised of a microcomputer 61, a relay contact 62 for controlling energization of the heating element 2, a relay coil 63, a transistor 64, and a resistor 66°86.67.68.69.

To is a commercial power supply, 8o is a DC power supply, a diode 81,
It is composed of resistors 82 and 83, a capacitor 84, and a constant voltage diode 86.

Next, the operation of the above circuit configuration will be explained. FIG. 2 shows a flowchart of a program stored in the microcomputer 61, and the operation will be explained according to the steps of the program shown in this flowchart. First, in step 1, it is determined whether there is water or not based on the signal from the phototransistor 22. At this time, if there is water, the float 23 is floating on the water in the water quantity display tube 7, so the light from the infrared LKD 21 reaches the phototransistor 22, and the phototransistor 22 is turned on.

In this case, proceed to step 2. Then, in step 2, it is determined whether the boiling mode is set, and if the boiling mode is not set, in step 3, the temperature of the thermistor 11 is detected by the temperature detection means 1o, and it is determined whether or not the temperature is higher than the heat retention temperature. If it is equal to or higher than the heat retention temperature, the heating element 2 is turned off in step 4, the heat retention LICD 40 is turned on in step 6, and the process returns to step 1. In addition,
If the temperature of the thermistor 11 is below the heat retention temperature in step 3, the heating element 2 is turned on in step 6, and it is determined in step 7 whether the temperature is higher than the heat retention temperature -6°C.

If the heat retention temperature is higher than -6°C, proceed to step 5, while if it is lower, proceed to step 8, then set the boiling mode and return to step 1.

If the boiling mode is set in step 2, the process proceeds to step 9, and in step 9 it is determined whether the water is boiling, and if it is not boiling, the heating element 2 is turned on in step 1o. Boil LKI in step 11) 30
Turn on the light and return to step 1. Further, if the water is boiled in step 9, the boiling mode is canceled in step 12 and the process returns to step 1.

Furthermore, in step 1, there is no water in the container 1, the float 23 moves to the lower end of the water quantity display tube 7, and the infrared LIED 2
1 light is blocked by the float 23 and the phototransistor 2
2 is OFF, proceed to step 13, set the heating element 2 to oyy, and in step 14 make the buzzer 61 sound beep, and turn off the water supply LK.
Blink D62 to notify that there is no water in container 1,
Return to step 1.

In the above embodiment, the water level detection means was composed of the infrared LICD 21, the phototransistor 22, and the float 23, but a method such as placing a magnet in the float and detecting with a reed switch may also be adopted. In short, any device that can detect that water is running out and output a signal is sufficient, and is not limited to the water level detection means of the above embodiments.

Effects of the Invention As described above, according to the present invention, if there is no water in the container, it is quickly detected, the current to the heating element is immediately stopped, and the user is alerted to water by sound or light. This makes it possible to provide an electric water heater that is safe, easy to use, and highly practical.

[Brief explanation of the drawing]

Fig. 1 is a circuit diagram of an electric water heater showing an embodiment of the present invention, Fig. 2 is a flowchart showing an example of a program of the electric water heater, and Fig. 3 is a cross-sectional view of a part of the electric water heater. 4 is a side view showing a part of a conventional electric water heater in cross section, and FIG. 6 is an electric circuit diagram of the electric water heater. 1... Container, 2... Heating element, 7...
...Water level display tube, 1o...Temperature detection means, 2
0... Water level detection means, 30... Boiling display element, 4o... Heat retention display element, 5o...
... Water supply notification means, 60 ... Control means. Name of agent: Patent attorney Toshio Nakao and 1 other person 2nd
111

Claims (1)

[Claims] A cylindrical container with a bottom, a heating element for heating water contained in the container, a temperature detection means for detecting the temperature of the water, and a water quantity display tube communicating with the inside of the container and extending in the vertical direction. ,
A water level detection means is installed adjacent to the water level display tube and outputs a signal depending on the presence or absence of water at the lower end, a boiling display element indicates that the water is being boiled, and a boiling display element indicates that the water is being kept warm. A heat retention display element for displaying, a water supply alarm means for notifying by sound or light that there is no water at the lower end of the water quantity display tube, and outputs of the temperature detection means and water level detection means are input, and the energization of the heating element is controlled. and boiling display element, heat retention display element,
An electric water heater comprising a control means for controlling a water supply notification means.