Microwave frequency-selective heating device and method thereof

Abstract

The present invention relates to a technical field of microwave heating, and more particularly to a microwave frequency-selective heating device and a method thereof. The microwave frequency-selective heating device includes: a heating chamber with a microwave feed-in device, and a frequency controller; wherein the frequency controller is connected to the microwave feed-in device. According to the microwave frequency-selective heating device and the method of the present invention, the heating frequency is adjusted by setting the microwave adjusting device, which improves a material heating uniformity while greatly increases a material microwave absorption rate, so as to solve a heating efficiency problem of the conventional technologies. According to the present invention, the frequency for the heated material is intelligently selected by the micro-processor of the microwave adjusting device, and then fed in after being adjusted by the frequency control circuit, which is effective and convenient.

Claims

1. A method for microwave frequency-selective heating, comprising steps of: A) inputting dielectric properties of a heated material through input buttons; B) according to the dielectric properties inputted in the step A), selecting a frequency from 300 GHz to 300 MHz by a micro-processor of a frequency controller; calculating an electric field, a magnetic field, a power dissipation and a temperature under the frequency by iteration, and calculating a coefficient of variation according to $\mathrm{Cov}=\frac{\sqrt{\frac{1}{N}\underset{i=1}{\overset{N}{.Math.}}{\left(T_i-\stackrel{\_}{T}\right)}^2}}{\stackrel{\_}{T}},$ wherein N is a number of total i-th points, T.sub.i is a temperature of an i-th point, T is an average temperature, and T is an average temperature rise, wherein T=T293.15K; storing the electric field, the magnetic field, the power dissipation, the temperature, and the coefficient of variation in a register; and C) selecting a heating frequency for the material, adjusting the heating frequency with a frequency control circuit, and heating the material with a microwave feed-in device.

2. The method, as recited in claim 1, further comprising a step D) of: connecting the frequency control circuit and the microwave feed-in device through a clock; wherein the step D) is executed between the step B) and the step C).

3. The method, as recited in claim 1, wherein the step B) specifically comprises a step of: adjusting the dielectric properties through temperatures.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) FIG. 1 illustrates an average temperature increase comparison of constant frequency heating and selective frequency heating.

(2) FIG. 2 illustrates a uniformity comparison of constant frequency heating and selective frequency heating.

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT

(3) The present invention provides a microwave frequency-selective heating device, comprising: a heating chamber with a microwave feed-in device, and a frequency controller; wherein the frequency controller is connected to the microwave feed-in device.

(4) Preferably, the frequency controller comprises a micro-processor for frequency selection, a register for storing selected frequencies, and a frequency control circuit; wherein the frequency control circuit is connected to the microwave feed-in device.

(5) Preferably, the frequency controller further comprises a displayer, and input buttons for inputting dielectric properties of a heated material, wherein the input buttons are connected to the micro-processor.

(6) Preferably, the microwave frequency-selective heating device further comprises a clock, wherein the frequency control circuit is connected to the microwave feed-in device through the clock.

(7) The present invention also provides a method for microwave frequency-selective heating, comprising steps of:

(8) A) inputting dielectric properties of a heated material through input buttons;

(9) B) according to the dielectric properties inputted in the step A), selecting a frequency from 300 GHz to 300 MHz by a micro-processor of a frequency controller; calculating an electric field, a magnetic field, a power dissipation and a temperature under the frequency by iteration, and calculating a coefficient of variation according to

(10) $\mathrm{Cov}=\frac{\sqrt{\frac{1}{N}\underset{i=1}{\overset{N}{.Math.}}{\left(T_i-\stackrel{\_}{T}\right)}^2}}{\stackrel{\_}{T}},$
wherein N is a number of total i-th points, T.sub.i is a temperature of an i-th point, T is an average temperature, and T is an average temperature rise, wherein T=T293.15K; storing the electric field, the magnetic field, the power dissipation, the temperature, and the coefficient of variation in a register; and

(11) C) selecting a heating frequency for the material, adjusting the heating frequency with a frequency control circuit, and heating the material with a microwave feed-in device.

(12) Preferably, the method further comprises a step D) of: connecting the frequency control circuit and the microwave feed-in device through a clock; wherein the step D) is executed between the step B) and the step C).

(13) Preferably, the step B) specifically comprises a step of: adjusting the dielectric properties through temperatures.

(14) Referring to FIG. 1 which illustrates an average temperature increase comparison of constant frequency heating and selective frequency heating, and FIG. 2 which illustrates a uniformity comparison of constant frequency heating and selective frequency heating, it is shown that after frequency selection, the heat efficiency is greatly increased without lowering the heating uniformity.

(15) According to the microwave frequency-selective heating device and the method of the present invention, the heating frequency is adjusted by setting the microwave adjusting device, which improves a material heating uniformity while greatly increases a material microwave absorption rate, so as to solve a heating efficiency problem of the conventional technologies. According to the present invention, the frequency for the heated material is intelligently selected by the micro-processor of the microwave adjusting device, and then fed in after being adjusted by the frequency control circuit, which is effective and convenient.

(16) One skilled in the art will understand that the embodiment of the present invention as shown in the drawings and described above is exemplary only and not intended to be limiting.

(17) It will thus be seen that the objects of the present invention have been fully and effectively accomplished. Its embodiments have been shown and described for the purposes of illustrating the functional and structural principles of the present invention and is subject to change without departure from such principles. Therefore, this invention includes all modifications encompassed within the spirit and scope of the following claims.