JPH0571742A - Cooking oven - Google Patents

Abstract

PURPOSE:To prevent wasteful power consumption of a cooking oven provided with a vapor sensor with a heater, and always perform excellent cooking using the vapor sensor. CONSTITUTION:A microcomputer 1 executes an automatic cooking in such a way that the microcomputer 1 controls a sensor heater 3 of a vapor sensor 2 so that the sensor heater 3 is turn on via a transistor 5 according to an automatic cooking commencement instruction and turn off when cooking is completed, and regulates a magnetron via a magnetron driving circuit 9 based on detecting signals Vs from the vapor sensor 2. The controller 1 measures an operating time period between the turn-off and the next turn-on of the sensor heater 3, and controls the cooking prohibition time period between the cooking commencement instruction and the start of cooking execution.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a heating cooker having a function of cooking based on a detection signal of a gas sensor having a heater.

[0002]

2. Description of the Related Art For example, in a microwave oven, a gas sensor for detecting gas such as water vapor emitted from food being cooked is provided, and energization to a magnetron, which is a heating means, is controlled based on a detection signal of the gas sensor. By doing
It is provided with automatic cooking.

[0003]

A gas sensor used in this type of microwave oven is provided with a heater. Conventionally, the gas sensor can always be detected by always energizing the heater. I was in a state.

However, in the above-mentioned conventional apparatus, the heater of the gas sensor is in the energized state even when the microwave oven is not used and during the manual cooking without using the gas sensor. It had the disadvantage of being wasted.

In order to deal with this, it has been considered that the heater is energized only during automatic cooking using a gas sensor. That is, the heater of the gas sensor is energized at the start of automatic cooking and cut off at the end of automatic cooking.

In this case, since the gas sensor needs a certain amount of time until the detection state is stabilized after the heater is energized, the cooking is started after a certain time has elapsed after the heater was energized. It is necessary to do so.

However, as described above, when the so-called cooking prohibition time from when the heater of the gas sensor is energized to when the cooking is started is constant, it means that the detection state of the gas sensor is stable. Since the gas sensor is not limited to this, there are cases where the gas sensor works well and there are cases where it does not work well, and if it does not work well, there arises a problem that cooking is not performed well.

The present invention has been made in view of the above circumstances, and an object thereof is to prevent unnecessary consumption of electric power by energizing the heater of the gas sensor only when it is necessary, and to realize the gas sensor. It is intended to provide a heating cooker that can always perform excellent cooking.

[0009]

DISCLOSURE OF THE INVENTION The present invention provides a heating means for heating an object to be heated housed in a heating chamber, and a gas sensor having a heater for detecting gas such as water vapor emitted from the object to be heated. In which the energization to the heating means is controlled based on the detection signal of the gas sensor, the heater of the gas sensor is energized based on the instruction to start cooking, and the power is cut off at the end of cooking. Control that controls the non-energization time from when the heater is cut off to when the heater is next energized, and controls the cooking prohibition time from the instruction to start cooking to the start of cooking based on the measured value. It is characterized in that means are provided.

Further, a non-volatile memory capable of reading and writing data is provided, and when the power supply is stopped by the control means at the time of measuring the non-energization time of the heater in the gas sensor, the data of the non-energization time during measurement is described above. It is preferable to be able to write in a non-volatile memory.

[0011]

According to the above means, the heater of the gas sensor is energized based on the instruction to start the cooking and is controlled to be cut off at the end of the cooking so that the sensor heater is energized only when the gas sensor is needed. Therefore, it is possible to prevent wasteful consumption of electric power.

By the way, in the case of a gas sensor having a heater, the time from when the heater is energized until the detection state is stabilized according to the magnitude of the non-energization time from when the heater is cut off to when it is next energized. Is changing.

That is, when the non-energization time is short, the time from when the heater is energized until the detection state is stable is short, but when the non-energization time is long, the detection state is stable after the heater is energized. Time to get longer.

Thus, in the above means, the non-energization time from when the heater is cut off to when the heater is next energized is measured, and based on the measured value, from the instruction to start cooking to the start of execution of cooking. Since the cooking prohibition time is controlled, cooking can always be performed in a state in which the detection state of the gas sensor is stable, and thus cooking can always be favorably performed.

On the other hand, at the time of measuring the non-energization time of the heater, when the power supply is stopped due to a power failure or the like, the measured non-energization time data is stored in the nonvolatile memory, and when the power supply is restarted, the data is stored. By reading out and using, it becomes possible to favorably perform cooking after power supply is restarted.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment in which the present invention is applied to a microwave oven will be described below with reference to the drawings.

In FIG. 1 showing an outline of an electrical configuration of a main part, a microcomputer 1 as a control means controls cooking and the like in accordance with a prestored program, which includes cooking time and time. A power pulse P corresponding to the commercial frequency is input as a time base serving as a reference of the.

The gas sensor 2, when expressed equivalently, comprises a sensor heater 3 and a sensor resistor 4,
The resistance value of the sensor resistor 4 changes according to the concentration of gas such as water vapor.

One end of the sensor heater 3 has a DC power source (V
DD), and the other end is connected to the collector terminal of the transistor 5 as a switching element. Further, one end of the sensor resistor 4 is also connected to the DC power source (VDD), and the other end is grounded via the resistor 6. The emitter terminal of the transistor 5 is grounded, and the base terminal is connected to the microcomputer 1 via the resistor 7. The resistor 8 has one end connected to a common connection point between the base terminal of the transistor 5 and the resistor 6, and the other end grounded.

Thus, the microcomputer 1 controls the on / off of the sensor heater 3 of the gas sensor 2 through the transistor 5, while the detection signal Vs of the gas sensor 2 is input to the microcomputer 1. ing.

Further, the microcomputer 1 includes
A magnetron drive circuit 9 for driving a magnetron (not shown) as a heating unit, an operation unit 10, a display unit 11, a readable / writable nonvolatile memory 12 and the like are connected.

Here, as shown in FIG. 2, the gas sensor 2 is energized by the sensor heater 3 in accordance with a non-energization time T from when the sensor heater 3 is disconnected to when it is next energized. There is a tendency that the time from when the detection is performed until the detection state is stabilized changes.

Therefore, the microcomputer 1 is provided with a timer for measuring the non-energization time T from when the sensor heater 3 is cut off to when it is next energized, and according to the non-energization time T, The cooking start instruction, that is, the data (see FIG. 3) in which the cooking prohibition time Ts is set from the start of energization of the sensor heater 3 until the detection state of the gas sensor 2 stabilizes, that is, the start of the execution of cooking is input. ..

Next, the operation of this embodiment will be described mainly with reference to the flowcharts (FIGS. 4 and 5) showing the control contents of the microcomputer 1.

First, when the plug (not shown) of the microwave oven main body is connected to a power outlet (not shown),
After initialization (step S1), data of the non-energized time T is read from the nonvolatile memory 12 (step S2).

In this case, since there is no data of the non-energized time T in the non-volatile memory 12 and the timer does not measure the non-energized time T, the process proceeds to step S5 according to each "N" of steps S3 and S4. To do. Step S5
In, the sensor heater 3 of the gas sensor 2 is forcibly turned on through the transistor 5 for a certain period of time, and the timer count is started in the state where the sensor heater 3 is cut off (step S6), and then the process proceeds to step S4. To do.

In this case, since the non-energization time T of the sensor heater 3 is being measured by the timer, the process proceeds to step S7 according to "Y". Then, while confirming that the power supply pulse P is input, the process waits until the start key of the operation unit 10 is operated (step S8).

When the start key is operated, it is determined whether or not automatic cooking is performed (step S9).
That is, in the case of manual cooking, the process proceeds to step S10 to execute manual cooking, and when the cooking is completed, the process returns to step S4.

When it is determined in step S9 that the cooking is automatic, the process proceeds to step S11 to stop the timer counting. As a result, the non-energization time T of the sensor heater 3 is measured. Then, in step S12, the cooking inhibition time TS is calculated based on the measured value of the non-energized time T based on the data of FIG.

Thereafter, the sensor heater 3 is turned on, and the process waits until the cooking prohibition time Ts elapses (steps S13 and S14). When the cooking prohibition time TS has passed, the magnetron drive circuit 9 drives and controls the magnetron to execute automatic cooking (step S15).

At this time, the gas sensor 2 detects gas such as water vapor emitted from the food to be cooked contained in a heating chamber (not shown), and the detection signal Vs is input to the microcomputer 1. The microcomputer 1 drives and controls the magnetron based on the detection signal Vs to execute automatic cooking.

When the automatic cooking is completed, the sensor heater 3 is turned off (step S16), the timer count is started (step S17), and then the process returns to step S4.

On the other hand, when the power supply is stopped while the sensor heater 3 is measuring the non-energization time T by the timer (when a power failure occurs or the user mistakenly unplugs the plug from the power outlet). Input), the input of the power supply pulse P to the microcomputer 1 is stopped.

Therefore, if it is determined in step S8 that the input of the power supply pulse P is stopped, the data of the non-energization time T during the measurement is immediately stored in the nonvolatile memory 12.
Write in.

When power is supplied again,
After the initialization in step S1, the data of the non-energization time T is read from the nonvolatile memory 12 in step S2, and the process proceeds to step S19 of FIG. 5 according to “Y” in step S3.

In step S19, the cooking prohibition time TS is calculated based on the data of the read non-energization time T based on the data of FIG. 3, and thereafter, the cooking prohibition time TS is turned on with the sensor heater 3 turned on. It waits until it passes (steps S20 and S21).

At this time, the sensor heater 3 is turned on for the cooking inhibition time TS according to the non-energization time T, so that the detection state of the gas sensor 2 can be temporarily stabilized. it can.

Then, the sensor heater 3 is turned off and the counting of the timer is started, and thereafter, the process proceeds to step S4 to return to the normal operation.

According to the present embodiment described above, the gas sensor 2
By controlling the sensor heater 3 to be energized based on an instruction to start automatic cooking and to be cut off at the end of cooking, the sensor heater 3 is energized only when the gas sensor 2 is needed, thus wasting power. It can prevent consumption.

Further, the non-energization time T from when the sensor heater 3 is cut off to when the sensor heater 3 is next energized is measured, and based on the measured value, the cooking prohibition time Ts from the instruction to start cooking to the start of execution of cooking. Since the control is performed, it becomes possible to always perform cooking in a state in which the detection state of the gas sensor 2 is stable, so that cooking can always be favorably performed.

Further, at the time of measuring the non-energization time T of the sensor heater 3, when the power supply is stopped due to a power failure or the like, the measured data of the non-energization time T is written and stored in the non-volatile memory 12, and the power is supplied. When that is resumed, the data is read out, and the sensor heater 3 is once energized according to the data, so that the detection state of the gas sensor 2 can be once made substantially stable,
The automatic cooking after restarting the power supply can be performed well.

In the above embodiment, the sensor heater 3 is turned on for 60 seconds during the cooking prohibition time Ts every time the non-energization time T of the sensor heater 3 reaches 48 hours, and then the sensor heater 3 is turned off. By measuring the non-energization time T in this state, it is possible to prevent the non-energization time T from becoming extremely long and the cooking prohibition time Ts from becoming extremely long.

[0043]

According to the heating cooker of the first aspect,
Energize the heater of the gas sensor based on the instruction to start cooking,
By controlling the power to be cut off at the end of cooking, wasteful consumption of electric power can be prevented. In addition, the non-energization time from when the heater of the gas sensor is cut off to when the heater is next energized is measured, and the cooking prohibition time from the instruction to start cooking to the start of cooking is controlled based on the measured value. By doing so, it becomes possible to always perform cooking in a state in which the detection state of the gas sensor is stable, and it is possible to always perform good cooking.

According to the second aspect of the present invention, when the power supply is stopped due to a power failure or the like when measuring the non-energization time of the heater in the gas sensor, the data of the non-energization time being measured is stored in a nonvolatile manner. By storing the data in the memory, and reading and using the data when the power supply is restarted, it is possible to favorably perform cooking after the power supply is restarted.

[Brief description of drawings]

FIG. 1 is a schematic electrical configuration diagram of a main part showing an embodiment of the present invention.

FIG. 2 is a diagram showing a change from when the sensor heater is energized until the sensor resistance value is stabilized.

FIG. 3 is a diagram showing a relationship between a non-energization time T and a cooking prohibition time Ts.

FIG. 4 is a flowchart showing the control contents of the microcomputer.

FIG. 5 is a flowchart showing the control contents of the microcomputer when power supply is restarted.

[Explanation of symbols]

1 is a microcomputer (control means), 2 is a gas sensor, 3 is a sensor heater (heater), 4 is a sensor resistance, 9
Is a magnetron drive circuit, and 12 is a non-volatile memory.

Claims (2)

[Claims] 1. A heating means for heating an object to be heated housed in a heating chamber, and a gas sensor having a heater for detecting a gas such as water vapor emitted from the object to be heated. In a device in which energization to the heating means is controlled based on a detection signal, the heater of the gas sensor is energized based on an instruction to start cooking and is controlled to be cut off at the end of cooking, and the heater is cut off. A control means is provided for measuring a non-energization time from when electricity is applied to when electricity is next applied, and based on the measured value, controlling a cooking prohibition time from an instruction to start cooking to the start of execution of cooking. Cooker to cook. 2. A non-volatile memory capable of reading and writing data, wherein the control means stores the data of the non-energization time during measurement when the power supply is stopped during the non-energization time of the heater in the gas sensor. A cooker characterized by being written in a non-volatile memory.