Microwave oven capable of suitably controlling movement of a member mounted thereto, and control method thereof

• US 6,586,714 B2
• Filed: 02/26/2001
• Issued: 07/01/2003
• Est. Priority Date: 02/29/2000
• Status: Expired due to Fees

• Current Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Original Assignee: Sanyo Electric Company Limited (Panasonic Holdings Corporation)
• Inventors: Noda, Masaru, Uehashi, Hiroyuki, Kawamura, Kazuhiko, Fukunaga, Eiji, Taino, Kazuo
• Primary Examiner(s): Leung, Philip H.
• Application Number:
  US09/791,820
• Publication Number:
  US 20010019054A1
• Time in Patent Office: 855 Days
• Field of Search: 219/710, 219/711, 219/494, 219/510, 219/720, 219/702, 219/754, 219/506, 374/149, 374/121, 993/25
• US Class Current: 219/711
• CPC Class Codes: H05B 6/6455 the sensors being infrared detectors
• CPC Class Codes: H05B 6/725 Rotatable antennas

Abstract

The microwave oven includes an infrared sensor for detecting the temperature of a food within a heating chamber. The infrared sensor has a field of view within the heating chamber. The infrared sensor is capable of moving the field of view. The food is often placed in the central region of the heating chamber. Therefore, when cooking is started, the field of view of the infrared sensor first scans the central region of the heating chamber.

Claims

1. A microwave oven, comprising:

a heating chamber for accommodating an object;

an infrared sensor having a field of view within the heating chamber, for detecting a temperature of the object in the heating chamber;

a field-of-view moving portion for moving the field of view of the infrared sensor, wherein the field-of-view moving portion moves the field of view in a central region of the heating chamber when temperature detection by the infrared sensor is started in the microwave oven; and

a presence determination portion for determining whether or not the object is present within the field of view of the infrared sensor, based on a detection result of the infrared sensor, wherein

the field-of-view moving portion extends a movement range of the field of view to a range broader than the central region of the heating chamber, if the presence determination portion determines that the object is not present in the central region of the heating chamber.

2. The microwave oven according to claim 1, wherein

the field-of-view moving portion starts moving the field of view when the heating operation of the heating portion is started, and

when the field-of-view moving portion extends the movement range of the field of view to the range broader than the central region of the heating chamber, the control portion reduces a heating output of the heating portion from a value that was used during movement of the field of view in the central region of the heating chamber, the reduced heating output being used until the presence determination portion determines that the object is present.

3. The microwave oven according to claim 1, further comprising:

a movement instruction portion for sending the field-of-view moving portion an instruction of whether to move the field of view or not;

a movement determination portion for determining whether the field of view is being moved or not; and

a notifying portion for notifying if a determination result of the movement determination portion is different from the instruction sent from the movement instruction-portion to the field-of-view moving portion.

4. The microwave oven according to claim 3, wherein the control portion discontinues the heating operation in response to the notification from the notifying portion.

5. A microwave oven, comprising:

a heating chamber for accommodating an object;

an infrared sensor having a field of view within the heating chamber, for detecting a temperature of the object in the heating chamber;

a field-of-view moving portion for moving the field of view of the infrared sensor, wherein the field-of-view moving portion moves the field of view in a central region of the heating chamber when temperature detection by the infrared sensor is started in the microwave oven,

a presence determination portion for determining whether or not the object is present within the field of view of the infrared sensor, based on a detection result of the infrared sensor;

a heating portion for heating the object in the heating chamber; and

a control portion for controlling the heating operation of the heating portion, wherein, if the presence determination portion determines that the object is not present in the central region of the heating chamber, the control portion discontinues the heating operation of the heating portion right after the movement of the field of view in the central region of the heating chamber is completed, or after a predetermined time has passed since the movement of the field of view in the central region of the heating chamber is completed.

6. A microwave oven, comprising:

a heating chamber for accommodating an object;

a heating portion for heating the object in the heating chamber;

an infrared sensor having a field of view within the heating chamber, for detecting a temperature of the object in the heating chamber;

a field-of-view moving portion for moving the field of view of the infrared sensor;

a demo executing portion for conducting a demonstration in which the field of view is moved and the infrared sensor is caused to conduct the temperature detection without operating the heating portion;

a presence determination portion for determining whether or not the object is present within

the field of view of the infrared sensor, based on a detection result of the infrared sensor, wherein

the field-of-view moving portion fixes a position of the field of view to a position of the object as determined by the presence determination portion, and

the temperature display portion displays a temperature detected by the infrared sensor with the position of the field of view fixed by the field-of-view moving portion.

7. The microwave oven according to claim 6, wherein the presence determination portion determines that the object is present at a certain position if a temperature detected by the infrared sensor with the field of view moved to the certain position is different at least by a predetermined value from a temperature detected by the infrared sensor with the field of view moved to a position adjacent to the certain position.

8. A method for controlling a microwave oven, wherein a field of view of an infrared sensor is moved in a central region of a heating chamber when the infrared sensor is caused to start temperature detection of an object within the heating chamber;

determining whether or not the object is present within the field of view of the infrared sensor, based on a detection result of the infrared sensor; and

determining a position of the object based on both a result of the determination whether or not the object is present within the field of view of the infrared sensor and a position of the field of view of the infrared sensor, wherein

if it is determined that the object is not present in the central region of the heating chamber, a movement range of the field of view is extended to a range broader than the central region of the heating chamber.

9. The method according to claim 8, wherein

the movement of the field of view of the infrared sensor is started when a heating operation of a heating portion is started, and

when the movement range of the field of view of the infrared sensor is extended to the range broader than the central region of the heating chamber, a heating output of the heating portion is reduced from a value that was used during movement of the field of view in the central region of the heating chamber, the reduced heating output being used until it is determined that the object is present.

10. The method according to claim 8, further comprising the steps of:

sending a member for moving the field of view of the infrared sensor an instruction of whether to move the field of view or not;

determining whether the field of view is being moved or not; and

notifying if a result of the determination whether the field of view is being moved or not is different from the instruction of whether to move the field of view or not.

11. The method according to claim 10, further comprising the step of:

discontinuing a heating operation of a heating portion if the result of the determination whether the field of view is being moved or not is different from the instruction of whether to move the field of view or not.

12. A method for controlling a microwave oven, wherein a field of view of an infrared sensor is moved in a central region of a heating chamber when the infrared sensor is caused to start temperature detection of an object within the heating chamber, further comprising the steps of:

determining whether or not the object is present within the field of view of the infrared sensor, based on a detection result of the infrared sensor; and

determining a position of the object based on both a result of the determination whether or not the object is present within the field of view of the infrared sensor and a position of the field of view of the infrared sensor, wherein

if it is determined that the object is not present in the central region of the heating chamber, a heating operation of a heating portion is discontinued right after the movement of the field of view in the central region of the heating chamber is completed, or after a predetermined time has passed since the movement of the field of view in the central region of the heating chamber is completed.

13. A method for controlling a microwave oven in which temperature detection by an infrared sensor is conducted with a field of view of the infrared sensor being moved within a heating chamber, wherein a demonstration of the infrared sensor is conducted by causing the infrared sensor to conduct the temperature detection without conducting a heating operation of a heating portion

determining whether or not an object is present within the field of view of the infrared sensor, based on a detection result of the infrared sensor;

fixing a position of the field of view of the infrared sensor to a position of the object determined as being present within the field of view; and

displaying a temperature detected by the infrared sensor with the position of the field of view being fixed.

14. The method according to claim 13, wherein in the step of determining whether or not the object is present within the field of view, it is determined that the object is present within the field of view when the field of view is located at a certain position if a temperature detected by the infrared sensor with the field of view moved to the certain position is different at least by a predetermined value from a temperature detected by the infrared sensor with the field of view moved to a position adjacent to the certain position.