JPS63294815A - 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 the Invention The present invention relates to electric water heaters used in homes and the like, and particularly to a heating control device thereof.

2. Description of the Related Art Conventionally, this type of electric water heater has had a configuration as shown in FIG. In FIG. 2, 1 is a container containing liquid 2, and 3 is a heating element, which is placed on the bottom side of the container 1. Reference numeral 4 denotes a temperature sensing element provided on the side surface of the container 1, which detects the temperature of the liquid 2. 6 is a detection circuit that extracts the temperature of the thermosensor 4 as an electric signal and determines the temperature of the liquid; 6 controls the supply of electricity to the heating element 3 according to the liquid amount and temperature; and a display section 7 that includes a lamp, a piezoelectric buzzer, etc. 8 is a power supply circuit.

Problems to be Solved by the Invention With such a conventional configuration, there is a problem that the container overheats in a short time when electricity is applied when the liquid amount decreases or when the container is in an empty state. This has been dealt with by energizing the container after confirming the amount of liquid in the container, or by controlling the energization of the heating element only when there is more than a certain amount of liquid.

The present invention is intended to solve these problems, and aims to prevent empty cooking by detecting the amount of liquid in the container using a temperature sensing element immediately after the heating element is energized.

Means for Solving the Problem In order to solve this problem, the present invention provides a container for containing a liquid, a heating element provided at the bottom of the container to heat the liquid, and a device for detecting the temperature of the liquid. After turning on electricity to the temperature sensing element attached to the side or bottom of the container and the heating body, turn off the electricity to 0FFL within 5 minutes, detect the temperature change of the temperature sensing element thereafter, and determine the liquid level. A liquid amount detection circuit, a temperature detection circuit that detects the temperature of the temperature sensing element when electricity is applied to the heating element, a control for controlling electricity supply to the heating element according to the liquid amount and temperature, a lamp, a piezoelectric buzzer, etc. The control circuit includes a control circuit that outputs an output signal to a display section, and a power supply circuit that drives the liquid amount detection circuit, temperature detection circuit, and control circuit.

Effect With this configuration, the current is temporarily turned off within 6 minutes immediately after power is applied to the heating element, the temperature curve of the thermosensor is determined, and when an abnormality occurs, it is determined that the heating is dry, and the current is controlled as OFF. By doing so, overheating of the container can be prevented.

Embodiment FIG. 1 is a diagram illustrating the configuration of an electric water heater according to an embodiment of the present invention, and the same parts as in the conventional example are given the same numbers. In FIG. 1, 1 is a container containing a liquid 2, and a heating element 3 is provided at the bottom of the container. By applying electricity to this heating body 3, the liquid 2 is heated.

Reference numeral 4 denotes a temperature sensing element, which is provided on the side (or bottom) of the container 1.

The temperature of the liquid 2 is electrically detected. 9 is composed of a switching circuit, a power converter, a comparator, and a timer, and turns off within 5 minutes immediately after energizing the heating element 3.
After F, by measuring the temperature of the temperature sensing element 4,
This is a liquid amount detection circuit that detects the liquid amount by detecting the temperature rise that appears during dry cooking.

Here, the energization time is determined based on the relationship between the energization time and the temperature rise of the container in the dry cooking state. do. For this reason, we decided to judge the amount of water in a short period of 5 minutes or less and decide whether or not to apply electricity in the future. In this case, although there are variations in the overheating of the container due to energization depending on the size and shape of the container, it was confirmed that there is no problem in any container as long as the heating is done within 6 minutes. 1o is a temperature detection circuit that detects the temperature of the temperature sensing element 4 when the heating element 3 is energized. Reference numeral 11 denotes a control circuit that receives signals from the temperature detection circuit 10 and the liquid amount detection circuit 9, controls energization, and outputs an operation signal to the display section 12. The display section 12 displays LΣD
It consists of a lamp, a piezoelectric buzzer, etc., and has the function of notifying the user of the electric water heater of the liquid level, etc. Reference numeral 13 denotes a power supply circuit, which is configured as a power source for driving the circuit described above and for driving a relay.

Effects of the Invention As described above, according to the present invention, the amount of liquid in the container is determined by detecting the temperature change of the temperature sensing element immediately after the initial energization of the heating element and after the energization is turned off within a short time. According to the configuration, when the amount of liquid is small, the heating element is energized for a short time and the amount of liquid is determined by the temperature sensing element, thereby making it possible to prevent overheating of the container. Moreover, the effect of determining the liquid amount can be obtained over a wide range of liquid temperatures.

[Brief explanation of drawings]

FIG. 1 is a diagram illustrating the configuration of an electric water heater according to an embodiment of the present invention, and FIG. 2 is a diagram illustrating the configuration of a conventional electric water heater. 1...container, 2...liquid, 3...
... Heating body, 4 ... Temperature sensing element, 9 ...
Liquid amount detection circuit, 1o...Temperature detection circuit, 11.
... Control circuit, 12 ... Display section, 13.
...Power supply circuit. Name of agent: Patent attorney Toshio Nakao and 1 other person No. 1
Figure 2

Claims (1)

[Claims] A container for containing a liquid, a heating element provided at the bottom of the container to heat the liquid, a temperature sensing element attached to a side or bottom surface of the container to detect the temperature of the liquid, and energizing the heating element. A liquid amount detection circuit that turns off electricity within 5 minutes after turning on, detects a subsequent temperature change in the temperature sensing element, and determines the liquid amount; a temperature detection circuit for detecting; a control circuit for controlling energization of the heating body according to the liquid volume and temperature; and a control circuit for outputting an output signal to a display unit including a lamp, a piezoelectric buzzer, etc.; and the liquid volume detection circuit; An electric water heater comprising a temperature detection circuit and a power supply circuit that drives a control circuit.