JPH11337078A - Heating and cooking device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To assuredly avoid a heating means from being turned on while the door of a heating chamber is opened even when a door switch does not normally operate. SOLUTION: In a microwave oven 1, when the door of a heating chamber is opened so that a door switch 30 connects a pont p to a point r, a power is supplied to a control circuit 25 from an external power source 40 to close a control switch 31. The control switch 31 is continuously closed until it is controlled to open by the control circuit 25. After the control switch 31 is closed, the door of the heating chamber is closed so that the door switch 30 connects a pont p to a point q. Then, magnetron 10 is brought into a state in which it can be connected to the external power source 40. Further, when the control circuit 25 closes a heating switch 33, the magnetron 10 performs a heating operation. Specifically, when the door switch 30 is not brought into both the states in which the point p is connected to the point r, and the point p is connected to the point q, the magnetron 10 cannot be connected to the external power source 40.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooking device and, more particularly, to a cooking device including a door switch for changing a connection state of a circuit in accordance with opening and closing of a door of a heating chamber. The present invention relates to a heating / cooking apparatus which is controlled so as not to perform heating when power supply to a control means is stopped and a door of a heating chamber is open.

[0002]

2. Description of the Related Art First, an example of a conventional microwave oven including a door switch will be described with reference to FIGS. 3 and 4. FIG.

FIG. 3A is a perspective view of a conventional microwave oven. The microwave oven 100 mainly includes a main body 2 and a door 3. The main body 2 is provided with an exterior part 4 that covers the outer periphery of the main body 2, a control panel 6, and a plurality of legs 8. The door 3 is provided with a handle 3 a for the user to open and close the door 3. FIG. 3B shows a state in which the door 3 of FIG. 3A is opened to the front. A heating chamber 5 is provided inside the main body 2 behind the door 3.

FIG. 4 is a diagram schematically and schematically showing the electrical configuration of the microwave oven shown in FIG.

Referring to FIG. 4, a microwave oven 100 includes a magnetron 10 for heating an object to be heated and a high-voltage transformer 11 for supplying a high voltage to the magnetron 10 at the back of the control panel 6 (see FIG. 3). It has. In the figure, reference numeral 40 denotes an external power supply for supplying power to the entire circuit shown in FIG.

The microwave oven 100 includes a control circuit 25 including a microcomputer for controlling the operation of the magnetron 10 and the like. Reference numeral 33 in the figure denotes a heating switch whose opening and closing are controlled by the control circuit 25 to control the energization of the high-voltage transformer 11. The control circuit 25
The microwave oven 100 is controlled in accordance with information input via the control panel 6 and the like. For example, when starting heating, the control circuit 25 closes the heating switch 33 and energizes the high-voltage transformer 11 and the magnetron 10.

A door switch 130 operates in conjunction with the operation of the door 3, and closes a circuit when the door 3 is closed, and opens the circuit when the door 3 is opened. When the door switch 130 is open, the external power 4
From 0, power is not supplied to the high-voltage transformer 11.
That is, the door switch 130 is provided to prevent the magnetron 10 from emitting microwaves while the door 3 is kept open, and to prevent the microwaves from being radiated outside the heating chamber.

Next, a description will be given of a conventional heating and cooking apparatus which automatically stops supplying power to the control means if heating is not performed for a predetermined time. Such a cooking device generally includes a switch for temporarily connecting the control means to an external power source and a switch for continuously connecting the two. Note that these two switches are provided in a heating cooking device configured to disconnect the control means and the external power supply as much as possible except when the user performs cooking using the heating cooking device, Generally, the former switch is temporarily operated by a user who intends to start heating cooking, and the latter switch is a switch operated by the control means when the control means and the external power supply are temporarily connected. is there.

Referring again to FIGS. 3 and 4, reference numeral 3 in FIG.
Reference numerals 1 and 32 denote a control switch and a power switch, respectively. Opening and closing of the circuit in the power switch 32 is controlled by the user. That is, when the user presses the power key 90 provided on the control panel 6 once,
The power switch 32 is configured to close the circuit while the power key 90 is pressed. Opening and closing of the circuit in the control switch 31 is controlled by the control circuit 25.

In the microwave oven 100, when the user temporarily presses the power key 90, the power switch 32 temporarily closes the circuit. Thus, the control circuit 25 is supplied with power from the external power supply 40 and is initialized. And
After the initialization, the control circuit 25
Close 1 continuously. Therefore, in the microwave oven 100, when the user temporarily presses the power key, the control switch 31 is continuously closed, so that the control circuit 25
Power is supplied continuously. If the microwave oven 100 does not perform the heating and cooking for a predetermined time, the control circuit 25 opens the control switch 31 and stops supplying power to the control circuit 25.

[0011]

However, microwave ovens 1
In the case of 00, the door switch 130 may not be opened due to welding or the like even when the door 3 is opened. Thus, in the microwave oven 100, there is a danger that the magnetron 10 is energized while the door 3 is open.

That is, in this type of conventional heating cooking apparatus, when the door switch is welded, the heating means may be energized even when the door of the heating chamber is open.
There was a problem of danger.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and it is an object of the present invention to ensure that the heating means is energized with the door of the heating chamber open even when the door switch does not operate normally. It is to provide a safe cooking device which can be avoided.

[0014]

According to a first aspect of the present invention, there is provided a heating and cooking apparatus, comprising: a heating unit for heating an object to be heated; a control unit for controlling a heating operation of the heating unit; And a door for opening and closing the heating chamber, and a first means for connecting the heating means to an external power supply when the door is in a closed state and disconnecting the control means from the external power supply. And a door switch in a second state for connecting the control means to an external power supply when the door is in the open state and disconnecting the connection between the heating means and the external power supply. The means is such that once the door switch assumes the second state, the connection between the control means and an external power supply is continued.

According to the first aspect of the invention, when the door of the heating chamber is opened, the door switch is in the second state, the control means and the external power supply are connected, and the heating means and the external power supply are connected. The connection will be disconnected. When the door of the heating chamber is closed, the door switch is in the first state, and the heating means and the external power supply are connected. Once the door switch is in the second state, the control means continuously connects the control means to the external power supply. That is, unless the door switch is in the second state, the control means is not continuously connected to the external power source, so that the heating means cannot perform the heating operation, and the door switch must be in the first state. In this case, since the heating means is not connected to an external power supply, the heating operation cannot be performed.

[0016] Thus, the heating and cooking apparatus is characterized in that the door switch switches between the first state and the second state according to the opening and closing of the door of the heating chamber.
The heating means cannot perform the heating operation unless both of the states are taken. Therefore, when the door switch cannot take both of the above states due to welding or the like, and does not operate normally, the heating means cannot perform the heating operation, and a safe heating cooking apparatus can be provided.

According to a second aspect of the present invention, in addition to the configuration of the first aspect of the present invention, the control means connects the control means to an external power supply. When the heating operation is not performed by the heating unit for a predetermined period of time, the connection between the control unit and an external power supply is disconnected.

According to the invention described in claim 2, according to claim 1,
In addition to the operation according to the invention described in above, when the door of the heating chamber is in the closed state, when the heating operation by the heating means is not performed for a predetermined time, the power supply to the control means is automatically released. .

Thus, in addition to the effect of the first aspect, unnecessary power supply to the control means can be avoided.
An energy efficient heating cooking device can be provided.

According to a third aspect of the present invention, in addition to the configuration of the first or second aspect, the control means is connected to an external power supply. It is characterized by further including a notifying means for notifying that the state is present.

According to the invention of claim 3, according to claim 1,
Alternatively, in addition to the operation according to the second aspect of the present invention, the notification unit notifies that the control unit is connected to the external power supply.

Thus, in addition to the effects of the invention described in claim 1 or 2, the user can grasp whether or not the control means is energized in the heating cooking device.

According to a fourth aspect of the present invention, in addition to the configuration of the first aspect of the present invention, the heating and cooking apparatus is connected in parallel with the heating means. A monitor switch that opens a circuit when the door is in a closed state and closes a circuit when the door is in an open state; and a fuse that is connected in series with the monitor switch and the heating unit. And

According to the invention of claim 4, according to claim 1,
In addition to the effect of the invention according to any one of claims 3 to 5, the control means and the external power supply are connected by a control switch, and the heating means and the external power supply are disconnected when the door is open. When it should be done, even if the heating means and the external power supply are connected due to a malfunction of the door switch, the fuse is blown and the connection between the heating means and the external power supply is cut off because the monitor switch closes the circuit.

Thus, in addition to the effect of any one of the first to third aspects of the present invention, it is possible to reliably prevent the heating means from heating when the door is open. .

[0026]

DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, a microwave oven according to an embodiment of the present invention will be described with reference to the drawings. In the present embodiment, a microwave oven is shown as an example of the heating cooking device. However, the heating cooking device of the present invention is not limited to this, and a door that changes a connection mode of a circuit according to opening and closing of a door of a heating chamber is described. A heating cooking device that includes a switch and automatically stops supplying power to the control means when heating is not performed for a predetermined time and does not perform heating when the door of the heating chamber is open, An oven toaster or the like may be used. In addition, since the microwave oven 1 of the present embodiment has substantially the same configuration as the conventional microwave oven 100, components having the same effect are denoted by the same reference numerals, and detailed description thereof is omitted. I do.

FIG. 1A is a perspective view of a microwave oven according to an embodiment of the cooking device of the present invention, and FIG.
FIG. 1A is a diagram showing a state in which the door 3 of FIG. The microwave oven 1 is placed on the control panel 6
The power supply lamp 50 is turned on when the power is supplied to the control circuit 25 and turned off when the power is not supplied to the control circuit 25. A turntable 15 for placing food is provided inside the heating chamber 5, and a heater (an upper heater 1 described later) is provided above and below the heating chamber 5, respectively.
2, a lower heater 13, not shown in FIG. 1).

FIG. 2 is a diagram schematically showing an electric circuit of the microwave oven 1. In FIG. 2, the microwave oven 1 includes a control circuit 25 including a microcomputer for controlling the operation of the microwave oven 1. The control circuit 25
It is connected to the control panel 6 and the thermistor 44. The thermistor 44 is provided near the heating chamber 5. Then, the control circuit 25 controls the microwave oven 1 according to the data and the like input from the control panel 6 and the thermistor 44.

The turntable motor 16 is a motor for rotating the turntable 15. And 2
Reference numeral 1 denotes a relay for turning on the turntable motor 16. In the figure, reference numerals 22 and 23 denote the upper heater 1 respectively.
2, a relay for turning on the lower heater 13; 33
Is a heating switch for energizing the transformer 11. In the figure, reference numeral 26 denotes a heating chamber light for illuminating the above-described heating chamber 5, and reference numeral 27 denotes a blower motor for driving a cooling fan of the magnetron 10. In the drawing, reference numeral 20 denotes a relay for energizing the heating chamber light 26 and the blower motor 27. The opening and closing of the relays 20 to 23 and the heating switch 33 are controlled by the control circuit 25. The opening and closing of the control switch 31 is also controlled by the control circuit 25.

In the figure, reference numeral 30 denotes a door switch. Although the door switch 30 of the present embodiment operates in conjunction with the door 3, unlike the door switch 130 of FIG. 4, when the door 3 is closed, the points p and q are connected, and when the door 3 is opened. p
It is configured to connect point and r point.

In the figure, reference numeral 41 denotes a monitor switch. The monitor switch 41 also operates in conjunction with the door 3, and when the door 3 is opened, the circuit shown in FIG. 2 is closed, and when the door 3 is closed, the circuit shown in FIG. 2 is opened. 29 is a fuse.

Next, the operation of the microwave oven 1 according to the present embodiment will be described. In the microwave oven 1, when the state where cooking is not performed for a predetermined time is continued, the control switch 31
Is open. From this state, once the door 3
Is opened, the door switch 30 is operated, the points p and r are connected, and the monitor switch 41 closes the circuit shown in FIG. When the door 3 is opened from the closed state, the points p and r are connected after the monitor switch 41 opens the circuit.

When the point p and the point r are connected while the control circuit 25 is not supplied with power, the control circuit 2
5 is supplied with power from the external power supply 40, and after being initialized, closes the control switch 31. At this time, the power lamp 50 that has been turned off is turned on. Here, the control switch 3
When 1 is closed, the control switch 31 is continuously closed until the control circuit 25 operates to open the control switch 31 as described later.

Then, through the control panel 6,
When an instruction to perform heating for a time T using the magnetron 10 (or the upper heater 12 and the lower heater 13) is input, the control circuit 25 causes the relay 21 and the heating switch 3 to operate.
After turning on the relay 3 (or the relay 22 and the relay 23) for the time T to perform the heating, they are turned off to terminate the heating.

After the completion of the heating, when a command to perform the heating is input via the control panel 6, the control circuit 25 causes the relay 21 and the relay 24 to respond accordingly.
(Or relays 22 and 23)
Heating is performed by the magnetron 10 (or the upper heater 12 and the lower heater 13).

On the other hand, when the microcomputer of the control circuit 25 detects that heating has not been performed for a predetermined time after the heating is completed, the control circuit 25 opens the control switch 31. At this time, if the door 3 is closed and the door switch 30 connects the points p and q, the power supply to the control circuit 25 is stopped. Thereby, the power lamp 50 is turned off. The predetermined time can be, for example, 5 minutes. That is, in the microwave oven 1, if heating is not performed for 5 minutes, the power supply to the control circuit 25 is automatically stopped if the door 3 is closed. Thereby, it is possible to prevent the control circuit 25 from being supplied with power unnecessarily.

In the microwave oven 1 described above, the door switch 30 is used to temporarily connect the switch for changing the circuit connection mode according to the opening and closing of the door 3, the control circuit 25 (control means), and the external power supply 40. And the control switch 31 constitutes a switch for continuously connecting the control circuit 25 and the external power supply 40.

That is, since the microwave oven 1 has the door switch 30, the microwave oven 1 has
There is no need to provide the power switch 32 (and the power key 90) separately from the door switch 30. Therefore, the microwave oven 1 can be manufactured with less components and at lower cost than the conventional microwave oven 100.

In the microwave oven 1, when the door 3 is opened when power is not supplied to the control circuit 25,
The point p and the point r are connected by the door switch 30 and energization to the control circuit 25 is started. When the door 3 is closed, the p-point and the q-point are connected by the door switch 30, and the high-voltage transformer 11 can be energized. That is, if the door switch 30 does not connect the points p and q even when the door 3 is closed, the control circuit 2
5 does not energize the high-voltage transformer 11 even if the heating switch 33 is closed. Further, if the door switch 30 does not connect the points p and r even when the door 3 is opened, the power supply to the control circuit 25 is not started and the control circuit 25 closes the heating switch 33. Can not. Therefore, in the microwave oven 1, the door switch 30
If both the state connecting the point and the q point and the state connecting the p point and the r point are not taken, that is, the door switch 30
If it does not work properly without welding, magnetron 1
0 means that heating cannot be performed. Therefore, the microwave oven 1 is configured so that the magnetron 10 does not heat when the door 3 is open.
The microwave oven 1 is provided with the door switch 30 as described above.
If welding does not work properly due to welding or the like, the normal operation can be performed again by replacing only the door switch 30.

In the microwave oven 1, while power is supplied to the control circuit 25, for example, the door switch 30
When the door 3 is opened due to welding or the like, the connection between the points p and q may not be disconnected even if the door 3 is opened, the monitor switch 41 closes the circuit. Can be avoided. That is, in such a case, the current flowing from the external power supply 40 is
Since the current flows from the monitor switch 41 to the fuse 29, the fuse 29 is blown. Thus, even if the heating switch 33 is further closed, the magnetron 10 is prevented from emitting microwaves.

In the embodiment described above, the heating means for heating the object to be heated is constituted by the magnetron 10. The control circuit 25 that controls the energization of the high-voltage transformer 11 constitutes a control unit that controls the heating operation of the heating unit. The door switch 30 constitutes a door switch that takes a first state in which the door is closed and a second state in which the door is open. The first state in which the heating means is connected to the external power supply and the control means is disconnected from the external power supply is a state in which the p point and the q point are connected, and the control means is connected to the external power supply. The second state in which the connection between the heating means and the external power supply is cut off is as follows.
This is a state where point p and point r are connected. Then, the control circuit 25 continuously closes the control switch 31 when the door 3 is opened, so that once the door switch takes the second state, the control means causes the control means and the external power supply to communicate with each other. It is disclosed that the connection is continued.

In the present embodiment described above, when the microcomputer of the control circuit 25 detects that the heating has not been performed for a predetermined time after the end of the heating,
When the control circuit 25 opens the control switch 31,
While the connection between the control means and the external power supply is continued, if the state where the heating operation is not performed by the heating means continues for a predetermined time, the control means informs that the connection between the control means and the external power supply is disconnected. It has been disclosed.

It should be noted that even if it is detected that the microwave oven 1 has not been heated for a predetermined time after the end of heating,
If the door 3 is open at that time, the control circuit 25 and the external power supply 40 are connected by the door switch 30. It is preferable that the microwave oven 1 further includes means for notifying the user by voice or the like if the door 3 is open when it is detected that such a state has continued. When the microwave oven 1 is configured in this manner, when the user notices the sound or the like and closes the door 3, the power supply to the control circuit 25 can be more reliably stopped when heating is not performed for a predetermined time.

Further, in the present embodiment described above, the notifying means for notifying that the control means is connected to the external power supply is constituted by the power lamp 50 which is turned on when the control circuit 25 is energized. Have been. The power supply lamp 50 may not be provided, and instead, when the control circuit 25 is energized, the heating chamber light 26 may be turned on. In this case, the heating chamber light 26 constitutes a notification unit.

The embodiments disclosed this time are to be considered in all respects as illustrative and not restrictive. The scope of the present invention is defined by the terms of the claims, rather than the description above, and is intended to include any modifications within the scope and meaning equivalent to the terms of the claims.

[Brief description of the drawings]

FIG. 1 is a diagram showing a microwave oven which is an embodiment of a heating and cooking device of the present invention.

FIG. 2 is a diagram schematically showing an electric configuration of the microwave oven of FIG.

FIG. 3 is a diagram showing a microwave oven which is an example of a conventional cooking device.

FIG. 4 is a diagram schematically showing an electric configuration of a microwave oven as an example of a conventional heating cooking device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Microwave oven 3 Door 5 Heating room 6 Control panel 10 Magnetron 11 High voltage transformer 25 Control circuit 29 Fuse 30 Door switch 31 Control switch 40 External power supply

Claims (4)

[Claims] 1. A heating unit for heating an object to be heated, a control unit for controlling a heating operation of the heating unit, a heating chamber for storing the object to be heated, a door for opening and closing the heating chamber, and the door. Takes a first state in which the heating means is connected to an external power supply when the door is in a closed state, and the control means is disconnected from the external power supply when the door is in an open state. And a door switch in a second state for disconnecting the heating means from the external power supply by connecting the heating means and the external power supply, wherein the control means, once the door switch takes the second state, A heating cooking device that maintains the connection between the control means and an external power supply. 2. The control device according to claim 1, wherein the control unit is connected to an external power supply when the heating operation by the heating unit is not performed for a predetermined time while the connection between the control unit and the external power supply is continued. 2. Disconnecting the connection with
A heating cooking device according to claim 1. 3. The heating and cooking apparatus according to claim 1, further comprising a notifying unit for notifying that the control unit is connected to an external power supply. 4. A monitor switch connected in parallel with said heating means, said monitor switch opening a circuit when said door is in a closed state and closing a circuit when said door is in an open state, and being connected in series with said monitor switch and said heating means. The heating cooking device according to any one of claims 1 to 3, further comprising a connected fuse.