Absolute-humidity detection device and method for cooking utensil and cooking utensil

Abstract

The embodiment of the invention provides an absolute-humidity detection device and method for a cooking utensil and the cooking utensil, and belongs to the field of home appliances. The device comprises a circuit board, a relative-humidity measuring device, a temperature measuring device and a controller, wherein the circuit board is installed to the side wall of an air discharging chamber of thecooking utensil, and a bottom layer of the circuit board faces the side wall; the relative-humidity measuring device comprises a humidity sensor and a capacitance detection module, and the capacitancedetection module is used for detecting the capacitance of the humidity sensor and outputting capacitance detection signals; the temperature measuring device is arranged on a bottom layer of the circuit board and used for detecting the temperature of steam at the air discharging chamber and outputting temperature detection signals; the controller is used for determining the relative humidity of steam at the air discharging chamber according to the capacitance detection signals, determining the temperature of the steam at the air discharging chamber according to the temperature detection signals and determining the absolute humidity of the steam at the air discharging chamber according to the relative humidity and the temperature. By means of the absolute-humidity detection device and method for the cooking utensil and the cooking utensil, the absolute humidity can be simply and accurately determined.

Description

technical field [0001] The invention relates to the field of home appliances, in particular to an absolute humidity detection device and method for cooking utensils and the cooking utensils. Background technique [0002] Since the dielectric loss factor of water is relatively large, when the temperature of the food rises (especially when the temperature of the food is greater than 80° C.) during the cooking process of the cooking utensils (for example, microwave ovens), the water evaporates relatively quickly. Humidity changes greatly, and the cooking status of food can be reflected through humidity detection, thereby realizing intelligent cooking. [0003] At present, commonly used humidity detection methods include relative humidity detection method and absolute humidity detection method. Among them, absolute humidity refers to the quality of water vapor contained in a unit volume of air, that is, the pressure of water vapor contained in air; The percentage value of the a...

AI Technical Summary

Problems solved by technology

[0007] (1) Since the Shibaura absolute humidity sensor uses a Huygens bridge differential detection circuit, an operational amplifier needs to be added to the detection circuit to filter and amplify the signal, so that it needs to be zeroed every time it is powered on to prevent the amplifier from being saturated. output; secondly, the sensor needs to be preheated before working to stabilize the temperature of the compensation resistor, but its temperature change and drift during the cooking process will lead to a decrease in the accuracy of humidity detection; in addition, the humidity sensor does not contain a temperature detection element, Therefore, the temperature of the water vapor in the cavity cannot be detected; finally, the cost of the Shibaura absolute humidity sensor is relatively high

[0008] (2) Although the cost of Kalida's other exciting buzzer absolute humidity sensor is low, its humidity detection accuracy is also low, and it is easily affected by environmental factors.

Although the change of humidity is small, if the wind is strong, the change of its output voltage is also large, so the environment such as external wind speed has a great influence on the accuracy, this detection scheme is not suitable for high-precision humidity detection; in addition, the humidity sensor is also Does not contain a temperature detection element, so the temperature of the water vapor in the cavity cannot be detected

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