JP2003042457A - Microwave oven - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a microwave oven to automatically close a door when a door is opened to take out a food after completion of cooking. SOLUTION: The microwave oven is provided with a heating chamber 3; a door 4 to open and close the opening of the heating chamber 3; a closing drive means for the door 4; a door switch 21 operated in linkage with opening and closing of the door 4; a food detecting means to detect whether a food is placed in the heating chamber 3; and a control part 23 to discriminate a food detecting result by the food detecting means. When opening of the door 4 is detected, it is detected by the food detecting means whether the food is taken out. When take-out of the food is detected, a closing means for the door 4 is driven and the door 4 is closed.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to a microwave oven.

[0002]

2. Description of the Related Art When a food is cooked in a microwave oven, the food is often hot, and the user often takes out the food by carefully grasping the edge of a container or the like. If the food storage location is further from the microwave oven location, the user will have to return to close the microwave oven door. Also, if you try to close the door with food in both hands, there is a fear that the food will be dropped.

[0003]

SUMMARY OF THE INVENTION The present invention provides a microwave oven which automatically closes the door when the door is opened and food is taken out after the cooking is completed.

[0004]

The first microwave oven according to the present invention comprises a heating chamber, a door for opening and closing the opening of the heating chamber, a closing drive means for the door, and the door. In a microwave oven equipped with a door switch that operates in conjunction with opening and closing, a food detection unit that detects whether food is placed in the heating chamber, and a control unit that determines a food detection result or the like by the food detection unit. When the opening of the door is detected, whether or not the food is taken out is detected by the food detection means, and when the taking out of the food is detected, the door closing drive means is driven to close the door. And

Accordingly, when the food is taken out by opening the door after the cooking is completed, the food detecting means can detect the taking out of the food and automatically close the door, so that the labor for closing the door can be omitted.

A second microwave oven according to the present invention includes a heating chamber, a door that opens and closes the opening of the heating chamber, a closing drive means for the door, and a door switch that operates in conjunction with the opening and closing of the door. Provided with a shelf in which the food is placed in the heating chamber, a weight detecting means for detecting whether or not the food is placed on the shelf, and a control section for determining a weight detection result or the like by the weight detecting means. In the microwave oven, when the opening of the door is detected, whether or not the food placed on the shelf is taken out is detected by the weight detecting means, and when the taking out of the food is detected, the door closing drive means is set. It is characterized by driving and closing the door.

Therefore, when the food is taken out by opening the door after the cooking is finished, the weight detecting means can detect the taking out of the food and automatically close the door, so that the labor for closing the door can be omitted.

In the third microwave oven according to the present invention, the closing drive means for the door is connected to a movable arm pivotally supported by the door and the other end of the arm. It is composed of a horizontal gear, a meshing gear that meshes with the horizontal gear, and a door opening / closing drive motor that rotates the meshing gear. The controller detects the opening of the door to detect the weight. By detecting the taking out of the food placed on the shelf by means, by driving the door opening and closing drive motor,
The door is closed by pulling the movable arm.

Therefore, when the food is taken out by opening the door after the cooking is completed, the weight detecting means can detect the taking out of the food and the door can be automatically closed, so that the labor for closing the door can be omitted.

[0010]

BEST MODE FOR CARRYING OUT THE INVENTION A microwave oven according to an embodiment of the present invention will be described with reference to the drawings. 1 is an external perspective view of the microwave oven when the door is opened, FIG. 2 is an enlarged view of the control portion, FIG. 3 is a cross-sectional view of the essential parts of the food detecting means, and FIG. 4 is the door closing when the door is closed. 6 is a plan view of the closing drive means, and FIG. 5 is a plan view of the door closing drive means when the door is closed.
Is a block diagram showing the configuration of the control circuit of the microwave oven main body,
FIG. 7 is a flow chart.

Referring to FIG. Microwave oven body 1
Is provided with a front plate 2. A heating chamber 3 is formed in the microwave oven main body 1, and a turntable 5 which is a shelf on which food is placed is provided at the bottom of the heating chamber 3. Door 4 for opening and closing the front opening of the heating chamber 3
Is provided with a door handle 4a, a latch claw 4b that is supported so as to be vertically swingable, and a protrusion 4c. When the door 4 is closed, the latch claw 4b enters into the microwave oven main body 1 through a hole (not shown) formed in the front plate 2 and a latch hook (not shown) arranged therein. No)). Further, the protrusion 4c also enters into the microwave oven main body 1 through a hole (not shown) formed in the front plate 2 and operates the door switch 21 (FIG. 4) arranged therein. A control section 7 is provided on the right side of the door 4. An arm 11 for driving the door closing is rotatably supported below the inside of the door 4.
It goes out of the slit 4d formed in the door 4 and enters into the lower side of the bottom surface of the heating chamber 3 through the slit 2a formed in the front plate 2.

The control section 7 shown in FIG. 2 is provided with various input keys 7a and automatic door closing keys 7b.

Next, a cross-sectional view of the main parts of FIG. 3 will be described. A turntable 5, which is a shelf on which food is placed, is placed on a cradle 6. Shaft 6 formed on this pedestal 6
The symbol a passes through the bearing 8 provided on the bottom surface 3a of the heating chamber 3 and moves up and down. The shaft 6a is connected to a turntable rotary shaft 16, and the turntable rotary shaft 16 has a turntable.
The bull gear 17 is fixed. This turntable gear 17 is a turntable driving motor (not shown).
It engages with a turntable motor gear 18 which is fixed to the rotary shaft 19 of FIG. Therefore, when the turntable driving motor is driven, the turntable 5 rotates.

The food detecting means, that is, the weight detecting means will be described below. Below the turntable gear 17, a weight sensor circuit board 13, a first capacitor foil 14 fixed to the weight sensor circuit board 13, and a tip of a turntable rotating shaft 16 are provided. A foil 15 of the second capacitor with which it is in contact is provided. Leaf springs 20 are provided on both ends of the foil 15 of the second capacitor, and the other ends of the leaf springs 20 are fixed. In addition, a capacitance detector 22 for detecting the capacitance between the first capacitor foil 14 and the second capacitor foil 15 is provided.
Is provided, and the capacitance detected by the capacitance detection unit 22 is input to the control unit 23 (FIG. 6). The capacitance is the foil 14 of the first capacitor.
And the distance between the foil 15 of the second capacitor.
In advance, the capacitance when no food is placed on the turntable 5 is stored in the control unit 23 as an initial value of the capacitance, and when the door 4 is opened, the capacitance detection unit 22 outputs the capacitance. The controller 23 compares the detected capacitance with the initial value of the capacitance. The control unit 23 (FIG. 6) detects whether food is placed on the turntable 5 by comparing the capacitances of the control unit 23. The comparison of the capacitances serves as food detection means (weight detection means) for detecting whether food is taken out. The operation of the food detection means (weight detection means) will be described below.

When food is placed on the turntable 5, the pedestal 6 is lowered due to the weight of the food, and the tip of the turntable rotating shaft 16 moves down the foil 15 of the second capacitor. It is displaced to the side and the capacitance at this time is detected. Next, when the door 4 is opened, the opening of the door 4 is detected,
When the food is taken out from the turntable 5, the force for displacing the foil 15 of the second capacitor downward disappears, and the repulsive force of the leaf spring 20 causes the foil 1 of the second capacitor 1 to be removed.
5 is displaced upward, and the capacitance at this time is detected. As described above, the first capacitor foil 14 is determined by whether food is placed on the turntable 5.
And the distance between the second capacitor foil 15 changes,
The capacitance changes. Even if the pedestal 6 is lowered, the bottom surface of the pedestal 6 does not come into contact with the bottom surface of the heating chamber 3, and the turntable gear 17 and the turntable are provided.
The gear 18 for the bull motor is prevented from being disengaged. As described above, the food detecting means (weight detecting means) includes the turntable 5, the pedestal 7, the turntable rotating shaft 16, the first condenser foil 14 and the second condenser foil. 15, a leaf spring 20, a capacitance detector 22, and a controller 23.

Next, the door closing drive means will be described with reference to FIG. One end of the arm 11 is movably supported below the inside of the door 4, and the other end thereof is supported by the horizontal gear 10. The horizontal gear 10 is a meshing gear 9 fixed to a shaft 12a of a door driving motor 12.
Is meshed with. As described above, the door closing drive means is composed of the arm 11, the horizontal gear 10, the meshing gear 9, and the door driving motor 12.

After the cooking is completed, when the door 4 is opened, the control section 23 detects whether or not the food is taken out from the turntable 5 by the food detecting means (weight detecting means) described above. In the control unit 23, the food is
When it is detected that it is taken out from the bull 5, the door driving motor 12 is energized to rotate the meshing gear 9 to the right. Then, the horizontal gear 10 is moved to the rear side,
The arm 4 is pulled to close the door 4. Therefore, when the food is taken out by opening the door after the cooking is finished, the taking out of the food can be detected by the food detecting means (weight detecting means), and the door can be automatically closed. You can FIG. 5 shows a state in which the door 4 is closed. When the door 4 is closed, the protrusion 4
Since the door switch 21 is operated at c, the closing of the door 4 is detected, and the energization of the door driving motor 12 is turned off. The shelf on which the food is placed is the turntable of the above embodiment.
Not a bull, but a shelf that doesn't rotate.

Next, a block diagram showing the configuration of the control circuit of FIG. 6 will be described. The control unit 23 receives an opening / closing signal of the door switch 21, a signal from the key input unit 7a for cooking provided in the operation unit 4, an automatic door closing key input signal, a signal from the capacitance detection unit 22 and the like. It The control unit 23 controls the turntable driving motor, the door driving motor 12, the high frequency oscillating circuit, etc. based on the control programs based on the input signals.

Next, the flow chart of FIG. 7 will be described. After turning on the power, close the door (step S1),
Various keys are pressed on the control section 7 to input keys (step S2) to start cooking. Next, it is detected whether or not cooking is completed (step S3). If the cooking is completed (YES in step S3), it is detected whether or not the door automatic closing key 7b is pushed in advance to set the door automatic closing mode (step S4). If the automatic door closing mode is selected (YES in step S4), it is detected whether there is an input cancel key operation of the automatic door closing key 7b (step S4).
5). If it is not the door automatic closing mode (NO in step S4), the process ends. If there is an input cancel key operation for the door automatic closing key 7b (YES in step S5), the door drive motor remains off (step S5).
8). If there is no input cancel key operation of the door automatic closing key 7b (NO in step S5), it is detected whether the door is closed (step S6). If the door is closed (YES in step S6), the door drive motor remains off (step S8). If the door is not closed (NO in step S6), the control unit 23 detects whether the food is taken out of the heating chamber (step S7). If the food is not taken out of the heating chamber (NO in step S7), the door driving motor remains off (step S8). If the food is taken out of the heating chamber (YES in step S7)
S), the door drive motor is turned on (step S9). Next, it is detected whether the door is closed (step S10).
If the door is closed (YES in step S10),
The door drive motor is turned off (step S11), and the process ends.

[0020]

The effect of the invention is that when the food is taken out by opening the door after the cooking is completed, the door can be automatically closed, so that the labor for closing the door can be omitted.

[Brief description of drawings]

FIG. 1 is an external perspective view of a microwave oven when a door is opened according to an embodiment of the present invention.

FIG. 2 is an enlarged view of a control section.

FIG. 3 is a sectional view of an essential part of a food detection means.

FIG. 4 is a plan view of a door closing drive means when the door is closed.

FIG. 5 is a plan view of a door closing drive means when the door is closed.

FIG. 6 is a block diagram showing a configuration of a control circuit of the microwave oven main body.

FIG. 7 is a flow chart.

[Explanation of symbols]

1 Microwave oven body 4 doors 4c protrusion 6 cradle 7 Control section 8 bearings 9 meshing gear 10 horizontal gears 11 Arm 12 Door drive motor 14 First capacitor foil 15 Second capacitor foil 16 turnable rotary shaft 20 leaf spring 21 door switch 22 Capacitance detector 23 Control unit

─────────────────────────────────────────────────── ─── Continued Front Page (51) Int.Cl. ⁷ Identification Code FI Theme Coat (Reference) F24C 15/16 F24C 15/16 J

Claims (3)

[Claims] 1. A heating chamber, a door that opens and closes the opening of the heating chamber, a closing drive means for the door, a door switch that operates in conjunction with opening and closing of the door, and a food item placed in the heating chamber. In a microwave oven equipped with a food detection means for detecting whether or not the food is detected, and a control section for discriminating the food detection result by the food detection means, when the opening of the door is detected, the presence or absence of food removal A microwave oven, characterized in that, when the food is taken out by the means, the closing drive means for the door is driven to close the door. 2. A heating chamber, a door that opens and closes the opening of the heating chamber, a closing drive means for the door, a door switch that operates in conjunction with opening and closing of the door, and a food provided in the heating chamber. In a microwave oven equipped with a shelf to be placed, a weight detection means for detecting whether food is placed on the shelf, and a control section for determining the weight detection result by the weight detection means, etc., the opening of the door is performed. When it is detected, whether or not the food placed on the shelf is taken out is detected by the weight detecting means, and when the food is taken out, the closing drive means of the door is driven to close the door. Characteristic microwave oven. 3. The microwave oven according to claim 2,
The door closing drive means includes a movable arm pivotally supported by the door, a horizontal gear connected to the other end of the arm, and a meshing gear meshed with the horizontal gear. When,
A door opening / closing drive motor for rotating the meshing gear, wherein the control section detects opening of the door, and the weight detecting means detects removal of the food placed on the shelf. The microwave oven characterized in that the door opening / closing drive motor is driven to pull the movable arm to close the door.