Dry heating prevention method of liquid heating device and heating device using dry heating prevention method

Abstract

The invention relates to the field of liquid heating, in particular to a dry heating prevention method of a liquid heating device and a heating device using the dry heating prevention method. The dry heating prevention method comprises the following steps that a temperature sensing part is used for detecting the temperature of the surface of a heating element and then transfers a temperature signal to a control unit, and the control unit calculates a temperature change rate of the surface of the heating element by two or more temperature spots so as to judge the working state of the heating element. Compared with the traditional method for judging the working state of the heating element by a single-spot temperature, the dry heating power-off time is not affected by the response delay of a temperature controller or a temperature sensor, so that the dry heating prevention method of a liquid heating device is more accurate in temperature control and can effectively prevent the heating element from being in a dry heating state for a long time. In addition, the temperature sensing part such as a thermistor or a thermocouple is used for directly detecting the temperature of the surface of the heating element so that the temperature sensing is fast and sensitive; and compared with the traditional metal temperature-sensing piece, the response delay time is greatly reduced so as to prevent the temperature of the heating element from being over-high and prolong the service life of the heating element.

Description

technical field [0001] The invention relates to the field of liquid heating, in particular to a method for preventing dry burning of a liquid heating device and a heating device thereof. Background technique [0002] With the rapid development of my country's economy, electric heating of liquids has been widely used in various fields, and many devices for electric heating of liquids have also appeared. In the existing instant water heaters using glass heating tubes, the dry-boiling protection is generally double protection. The first is to use the liquid level switch to prevent water shortage in the water pipe; the second is to use the fuse to cut off the power. Product does not work properly. However, in the above-mentioned protection, the fuse directly cuts off the power, and cutting off the connection with the power supply is easy to damage the performance of the product; and the data of the water level detected by the liquid level switch is not accurate enough. [0003...

AI Technical Summary

Problems solved by technology

The disadvantage of this anti-dry burning method is that the power-off time of dry burning is affected by the temperature response delay of the thermostat or temperature sensor, and it is impossible to achieve precise temperature control. The temperature response of the thermostat or temperature sensor is delayed, causing the temperature to be too high

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