Microwave treatment device

Patent metadata

Field	Value
Publication number	US-12484120-B2
Application number	US-202017608209-A
Country	US
Kind code	B2
Filing date	Jul 28, 2020
Priority date	Jul 31, 2019
Publication date	Nov 25, 2025
Grant date	Nov 25, 2025

Abstract

A microwave treatment device comprises: a heating chamber that accommodates an object to be heated; a microwave generator that generates a microwave in a specified frequency band; an amplifier that amplifies the microwave; a feeding unit that supplies the amplified microwave to the heating chamber; a detector that detects a reflected microwave power; and a controller. The controller selects one of plural frequencies in the specified frequency band and causes the microwave generator to generate the microwave with the selected frequency. The controller causes the amplifier to change an output power of the microwave so that the microwave supplied to the heating chamber has one of plural output powers. The controller measures a reflected microwave frequency characteristic based on reflected microwave powers detected under each of a condition that the microwave has a first output power and a condition that the microwave has a second output power.

First claim

The invention claimed is:

1 . A microwave treatment device comprising:
a heating chamber configured to accommodate a heating target; a microwave generator configured to generate a microwave with a frequency in a specified frequency band; an amplifier configured to amplify the microwave generated by the microwave generator; a feeding unit configured to supply the microwave amplified by the amplifier to the heating chamber; a detector configured to detect a reflected microwave power returned through the feeding unit; and a controller configured to control the microwave generator and the amplifier, wherein the controller selects one of a plurality of frequencies in the specified frequency band and causes the microwave generator to generate the microwave with the selected frequency, the controller causes the amplifier to change an output power of the microwave so that the microwave supplied to the heating chamber has one of a plurality of output powers, the controller measures a reflected microwave frequency characteristic based on reflected microwave powers detected under each of a condition that the output power of the microwave is a first output power and a condition that the output power of the microwave is a second output power, where the first output power and the second output power are included in the plurality of output powers and the first output power is a lower power than the second output power, and the controller determines an in-chamber loss frequency band based on a first reflected microwave frequency characteristic measured under the condition that the output power of the microwave is the first output power and a second reflected microwave frequency characteristic measured under the condition that the output power of the microwave is the second output power.

2 . The microwave treatment device according to claim 1 , wherein the controller is configured to determine a frequency of a microwave that is to be used for cooking based on a first reflected microwave frequency characteristic measured under the condition that the output power of the microwave is the first output power and a second reflected microwave frequency characteristic measured under the condition that the output power of the microwave is the second output power.

3 . The microwave treatment device according to claim 2 , wherein the controller is configured to select a same frequency as a frequency of the microwave under each condition that the output power of the microwave is any of the plurality of output powers.

4 . The microwave treatment device according to claim 2 , wherein the controller is configured to cause the microwave generator to generate the microwave while executing a frequency sweep over the specified frequency band.

5 . The microwave treatment device according to claim 2 , wherein the controller is configured to first measure the first reflected microwave frequency characteristic, and successively measure the second reflected microwave frequency characteristic.

6 . The microwave treatment device according to claim 2 , wherein the first output power is lower than 100 W and the second output power is equal to or higher than 100 W.

7 . The microwave treatment device according to claim 2 , wherein the controller is configured to measure the first reflected microwave frequency characteristic and the second reflected microwave frequency characteristic within five minutes after a start of cooking.

8 . The microwave treatment device according to claim 2 , wherein the controller is configured to store in a storage unit, as an in-chamber loss frequency band, a frequency band in which a difference between the first reflected microwave frequency characteristic and the second reflected microwave frequency characteristic exceeds a predetermined threshold value.

9 . The microwave treatment device according to claim 8 , wherein the controller is configured to store in the storage unit, as the load loss frequency, a frequency at which the reflected microwave frequency characteristic becomes the minimum value or a local minimum value in the frequency band that is excluded from the in-chamber loss frequency band.

10 . The microwave treatment device according to claim 9 , wherein the controller is configured to select the load loss frequency as a frequency of the microwave that is to be used for cooking.

11 . The microwave treatment device according to claim 9 , wherein the controller is configured to store in the storage unit, as initial values, the first reflected microwave frequency characteristic, the second reflected microwave frequency characteristic, the in-chamber loss frequency band, and the load loss frequency.

12 . The microwave treatment device according to claim 11 , wherein the controller is configured to measure again the first reflected microwave frequency characteristic and the second reflected microwave frequency characteristic halfway through cooking, and to update the initial values stored in the storage unit.

13 . The microwave treatment device according to claim 8 , wherein the controller is configured to weight a detection value of the reflected microwave power in a case of using the reflected microwave frequency characteristic in the in-chamber loss frequency band for determining progress of cooking.

Assignees

• Panasonic Ip Man Co Ltd

Inventors

• Oomori Yoshiharu
• Hosokawa Daisuke
• Yoshino Koji
• Maeda Kazuki
• Uno Takashi
• Hiramoto Masayoshi
• Ogasawara Fumitaka

Classifications

• H05B6/687

  for cooking · CPC title

• H05B6/6447

  Method of operation or details of the microwave heating apparatus related to the use of detectors or sensors · CPC title

• H05B6/705

  using microwave tuning · CPC title

• H05B6/686 Primary

  Circuits comprising a signal generator and power amplifier, e.g. using solid state oscillators · CPC title

• H05B6/68 Primary

  for monitoring or control · CPC title