JPH0499536A - Electric hot-water heater - Google Patents

Abstract

PURPOSE:To shorten the time for boiling water by constituting the hot-water heater so that a control means drives a heating control element and a warming control element at the time of boiling hot water, and controls a temperature in a vessel by driving the warming control element at the time of warming. CONSTITUTION:When an AC power source 3 is applied, a temperature is decided, and when it is below a temperature for executing warming, a heating element l and a warming heating element 5 are conducted electrically by driving a heating control means 2 and a warming control means 6, and whether water is boiling up or not is decided. When boiling is detected, the electric conduction of the heating heating element l and the warming heating element 5 is stopped. Subsequently, when the temperature is above a warming temperature, the warming heating element 5 is conducted electrically and whether the temperature is above a temperature (95 degrees) for temperature control or not is decided. In this case, in the case it is lower than the temperature for temperature control, the warming heating element 5 is conducted electrically by driving a warming control element 6.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an electric water heater for heating and keeping a liquid contained in a container warm.

BACKGROUND OF THE INVENTION In recent years, electric water heaters have become mainstream for heating liquid in a container and keeping it warm.

Conventionally, this type of electric water heater heats the liquid contained in the container by energizing the heating element during boiling water.
While keeping the container warm, the heating element was energized to keep the liquid inside the container warm.

Problems to be Solved by the Invention In such conventional electric water heaters, there is a problem in that heat exchange efficiency is low because the heating element for heating and the heating element for keeping warm are separately arranged at the bottom of the container. Furthermore, when shortening the boiling time, it is necessary to design a new heating element to increase the power of the heating element, which requires a lot of time and increases the number of types of heating elements. The present invention solves the above problems by improving heat exchange efficiency,
The aim is to shorten the time required to boil water using the same heating element.

Means for Solving the Problems In order to achieve the above object, the present invention provides a heating element,
A heating control element that controls energization of the heating element, a heat-retaining heating element, a heat-retaining control element that controls energization of the heat-retaining heating element, and a control that controls operations of the heating control element and the heat-retaining control element. means, the control means drives the heating control element and the heat retention control element when boiling water, and drives the heat retention control element when keeping water warm to control the temperature inside the container. It is said that

Effect of the present invention By using the above-mentioned problem-solving means, by simultaneously energizing the heating element and the heat-retaining heating element during heating, the bottom of the container can be heated uniformly and the heat exchange efficiency can be improved. Power can be easily increased without any new design, and the time required to boil water can be shortened.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to FIG.

As shown in the figure, the heating element l comes into contact with the container (not shown) of the electric water heater and heats the liquid in the container, and connects the relay contacts 2a forming the heating control element 2 in series. Connected to AC power supply 3. The heating control element 2 includes a relay contact 2a, a relay coil 2b, and a transistor 2.
The relay contact 2a is opened and closed by causing a current to flow through the relay coil 2b via the transistor 2C in response to an output signal from the control means 4. The heat-retaining heating element 5 comes into contact with the container of the electric water heater to heat and keep the liquid inside the container warm, and is connected in series with a relay contact 6a constituting a heat-retaining control element 6, and connected to the AC power source 3. The heat retention control element 6 includes a relay contact 6a and a relay coil 6.
b and a transistor 6C, and the relay coil 6b is connected via the transistor 6C by the output signal of the control means 4.
By flowing a current through i:, the relay contact 6a is opened and closed.

The control means 4 includes a thermistor 4a that converts the temperature inside the container into a resistance value, an AD converter 4b that converts the value of the thermistor 4a into a binary code, and a heating control element 2 using the output of the AD converter 4b as input. and a microcomputer 4c that outputs output to the heat retention control element 6.

The operation of the above configuration will be explained with reference to a flowchart of a program stored in the microcomputer 4c shown in FIG.

First, when the AC power source 3 is applied, the temperature is determined in step 11. If the temperature is higher than the temperature at which heat retention is performed, the process proceeds to step 12. If the temperature is below the temperature required to keep warm, the heating control means 2 and the heat keeping control means 6 are driven in step 13 to energize the heating element 1 and the heat generating element 5, and in step 14 it is determined whether or not the temperature is boiling. do. Here, step 13. until boiling is detected. Skip 14
When boiling is detected by repeating this process, the process proceeds to step 15, where the energization of the heating element 1 and the heat-retaining heat generating element 5 is stopped, and the process returns to step 11. Next, in step 11, save a is
If the temperature is higher than 0.5 degrees, it is determined in step 12 whether the temperature is equal to or higher than the temperature at which the heat-retaining heating element 5 is energized to adjust the temperature (95 degrees in this embodiment). Here, if the temperature is higher than the temperature to be adjusted, the process proceeds to step 15. If the temperature is lower than the wet temperature, proceed to step 16 (:), drive the heat retention control element 6 to energize the heat retention heating element 5, and return to step 11. Repeat until.

Effects of the Invention As is clear from the above embodiments, according to the present invention, the control means drives the heating control element and the heat retention control element when boiling water, and drives the heat retention control element when keeping the water warm to control the temperature inside the container. Because of this control, when boiling water, the heating element and the heating element for keeping warm can be energized at the same time, and the bottom of the container can be heated evenly, improving heat exchange efficiency. Boiling time can be shortened by using the same heating element and heat-retaining heating element without using a high-wattage heating element.

[Brief explanation of the drawing]

FIG. 1 is a circuit diagram of an electric water heater according to an embodiment of the present invention.
FIG. 2 is an operational flowchart of the electric water heater. DESCRIPTION OF SYMBOLS 1... Heat generating element for heating, 2... Heat control element, 4... Control means, 5... Heat generating element for heat retention, 6... ...Moisturizing control element.

Claims (1)

[Claims] a heating element for heating, a heating control element that controls energization of the heating element, a heating element for heat retention, a heat retention control element that controls energization of the heat retention element, and a combination of the heating control element and the heat retention control element. and a control means for controlling the operation, the control means driving the heating control element and the heat retention control element when boiling water, and driving the heat retention control element when keeping the water warm to control the temperature inside the container. An electric water heater.