JP2001176652A - Heating cocker - Google Patents

Abstract

PROBLEM TO BE SOLVED: To offer a heating cooker saving power consumption in which even after a power-source switch is turned off, a display or a fan motor is operated. SOLUTION: After supplying a power to an inverter 27 and a heating section control circuit 30 through the power-source switch 21, the power is supplied to a power supply line to the heating section control circuit 30 through a relay 31. When a control instruction of an inverter 27 is not inputted for a predetermined time, the relay 31 is turned off, and when an waited input control instruction comes, the relay 31 is turned on. With this procedure, a reliable heating cooker with long life parts as well as saving power consumption can be provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cooking device used for home and business use.

[0002]

2. Description of the Related Art Conventionally, even after a power switch is turned off,
Monitor the top plate temperature to indicate whether it is hot, or monitor the internal temperature of the device and turn the cooling fan motor to reduce the performance degradation due to the rise in the temperature of the internal electronic components due to the residual heat of the heating section. Preventive cookers have been developed.

[0003] A conventional heating cooker will be described below. FIG. 2 is a circuit block diagram of the inside of the heating cooker having the heater 7 and covered with a ceramic plate on the top. A series circuit of a heater 7 and a relay contact 8b of a relay 8 and a drive coil 3a of a relay 3 are connected to a commercial power supply 1 via a power switch 2. The commercial power supply 1
A series circuit of a fan motor 12 and a relay 13b, a parallel circuit of a relay contact 3b of a relay 3 and a relay contact 4b of a relay 4, a series circuit of a primary winding of a power transformer 5, and a series circuit of a resistor 16 and a resistor 17 are connected. Have been.

[0004] The secondary winding of the power transformer 5 is connected to a power circuit 6, and the DC output voltage of the power circuit 6 is supplied to the microcomputer 10 as a control power voltage. The output of the power supply circuit 6 is connected to a series circuit of the drive coil 4a of the relay 4 and the transistor 9, a series circuit of the drive coil 13a of the relay 13 and the transistor 14, and a series circuit of the drive coil 8a of the relay 8 and the transistor 15. Is done. The output terminal of the microcomputer 10 is connected to the base of the transistor 9, the base of the transistor 14, the base of the transistor 15, and the anode of the LED 11.
A ground terminal of the microcomputer 10 includes a power supply line on one side of the commercial power supply 1, a negative electrode of an output voltage of the power supply circuit 6,
Transistor 9, Transistor 14, Transistor 15
And the cathode of the LED 11 are connected. The voltage divided by the resistors 16 and 17 is input to the microcomputer 10.

The operation will be described with reference to FIG. When the power switch 2 is turned on, a voltage is applied to the relay drive coil 3a, and the relay contact 3b is turned on. When the relay contact 3b is turned on, a commercial power supply voltage is applied to the primary winding of the power transformer 5, so that a DC control power supply voltage is output from the power supply circuit 6 connected to the secondary winding. The microcomputer 10 starts operating by supplying the control power supply voltage, and turns on the transistor 9. As a result, a voltage is applied to the relay drive coil 4a to turn on the relay contact 4b. Upon receiving the heating signal from the input device, the microcomputer 10 drives the transistor 15 to drive the relay contact 8
b is turned on and the heater 7 is energized. When the power switch 2 is turned off after the cooking is completed, no voltage is applied to the relay drive coil 3a, so that the relay contact 3b is turned off. The microcomputer 10 turns off the power switch 2 with the resistor 1
6 and the change in the divided voltage by the resistor 17, the LED is turned off after a predetermined time has elapsed after the power switch 2 is turned off, the transistor 14 is turned off, the relay contact 13b is turned off, and the operation of the fan motor is stopped. Relay contact 4b
Is turned off, and the power supply to the power supply circuit 6 is stopped.

[0006]

In the above cooking device, the closing phase of the relay contact 3b is random. When the power is supplied at the peak phase of the commercial power supply, the power supply circuit 6
Since the rush current to the smoothing capacitor becomes large, the contact may be welded when the contact capacity is small, and a relay having a large contact capacity is required. Further, the power supply to the power supply circuit 6 requires the relays 3 and 4 and their respective drive circuits, the relay 13 for driving the fan motor 12 and its drive circuit, and the DC power supply 6 and the transformer 5 having a large output current capacity are required. Required.

The present invention enables a microcomputer to perform a control operation even after a power switch is turned off.
Further, it is an object of the present invention to provide an inexpensive and highly reliable heating cooker capable of cutting off power supply to a microcomputer when control by the microcomputer becomes unnecessary.

[0008]

A heating unit, a heating control unit for controlling a heating operation of the heating unit, a first switch for turning on or off the power of the heating unit, and a power supply by the first switch. And a first control power supply path for supplying a control power to the heating control unit.
After the power is turned on to the heating unit and the first control power supply path by the switch means, the power is turned on to the second control power supply path by the second switch means. If not input, the power supply to the second control power supply path by the second switch means is released, and after that, a predetermined control command is input, and then the second switch means sets the second control power supply path to the second control power supply path. This is configured to supply power to the control power supply path.

Thus, even after the power supply to the heating unit is cut off by the first switch means, the heating control unit is operated to measure the time and input signals from various sensors.
Drives and displays components other than the heating operation as necessary, and finally shuts off the control power supply to itself, shortening the operation time, extending the life of the components, and saving power consumption. The drive time of the second control power supply path after the supply of the second control power by the second switch means is shortened, and the consumption accompanying the drive of the second switching means and the drive of the second control power supply path is reduced. An inexpensive and highly reliable heating cooker capable of reducing electric power can be obtained.

[0010]

DESCRIPTION OF THE PREFERRED EMBODIMENTS According to the structure of the first aspect of the present invention, since the first switch means for shutting off the power supply to the heating unit is provided, electronic components such as a microcomputer of the heating control unit may be damaged or malfunction. Even if you lose control due to runaway, etc.
It is safe because heating can be stopped reliably.

Further, when the cutoff state by the first switch is released, the control power is supplied to the heating control unit through the first control power supply path, so that the heating control unit becomes operable. The heating control unit immediately or after a predetermined time,
Alternatively, the second switch means may be controlled in accordance with a signal from an input device or the like, so that the control power can be supplied to the heating control unit. At this time, if the heating control unit detects the power supply phase with a microcomputer or the like, the heating control unit performs the second
By controlling the closing phase of the switching element, the inrush current can be minimized and the failure of the second switch means can be prevented.

After the first switch means cuts off power supply to the heating section, the heating control section controls the second switch means to cut off power supply to the second control power supply path. With this configuration, it is possible to wait for the completion of the control work required by the heating control unit, and then shut off the control power supply at an arbitrary timing. Therefore, even after the power supply to the heating unit is cut off by the first switch unit, the heating control unit is operated to measure time or input signals from various sensors, and to drive components other than the heating operation as necessary. In addition, the control power supply to itself is cut off, the operation time is shortened, the life of the components is extended, and the power consumption can be saved.

After the power is supplied to the heating unit by the first switch, the power is supplied to the first control power supply path by the first switch, and the second control power supply is supplied by the second switch. Power on, and if the control command of the heating unit is not input for a predetermined time, the second
The input operation to the second control power supply path by the switch means is stopped, and after the predetermined control command is input thereafter, the power supply to the second control power supply path by the second switching means is stopped. A heating cooker adapted to supply the second control power supply path after the second control power supply by the second switch means, thereby shortening the driving time of the second control power supply path; This has the effect of reducing power consumption associated with driving and driving the second control power supply path.

According to a second aspect of the present invention, there is provided a heating unit, a first switch unit for turning on or off a power supply to the heating unit, and a second switch unit for turning on or off a power supply to a cooling fan motor. After the power to the heating unit is turned on by the first switch means, the power is turned on to the fan motor by the second switch means. If a predetermined control command is not input for a predetermined time, the fan motor is turned on by the second switch means. A heating cooker configured to release the power supply to the fan motor, wait for a control command to be input thereafter, and then turn on the power to the fan motor by the second switch means. The drive time of the fan motor after the power supply to the fan motor by the switch means is shortened to extend the life, and the drive of the second switching means and the fan motor It is expected to have an effect that it is possible to reduce the power consumption due to the driving of the over.

According to a third aspect of the present invention, in addition to the configuration of the first or second aspect, a heating cooker is provided in which a predetermined control command is a heating command. In addition, the operation of the fan motor, the operation of the fan motor after the completion of cooking, and the display operation of the high temperature of the top plate, etc. can be performed to the extent that the control operation related to the cooking can be executed. This has the effect of shortening the time and extending the life.

According to a fourth aspect of the present invention, in addition to the configuration of the first to third aspects, after the power is turned on by the first switching means, the second switching means is connected to the start of the heating operation of the heating unit. By controlling the power supply to the second control power supply path, the voltage application time of the fan motor or the electronic component after the power is turned on by the first switch means is minimized, and the power consumption is further reduced. This has the effect of saving money and extending the life of the fan motor or electronic components.

[0017]

(Embodiment 1) An embodiment of the present invention will be described below with reference to the drawings. Fig. 1 shows two induction heating coils for heating with a high-frequency magnetic field and two heating element heaters for heating with the resistance of the heater itself (a roaster heater housed in a heating chamber and a load placed on the top). 2 shows a multi-port heating cooker having a top heater for heating).

An interlocking power switch 21 and a power switch 41 are connected to one bus of the commercial power supply 20, and a full-wave rectifier 25 and a primary winding of a power transformer 22 are connected to load terminals of the power switch 21. A fuse 62 is connected between a connection point between the commercial power bus on the side to which the switch 21 is not connected, the primary winding of the power transformer 22, and the input terminal of the rectifier 25. The load side terminal of the power switch 41 has a full-wave rectifier 42 input terminal, a series circuit of a relay contact 52 and a roaster heater 53, a relay contact 54 and a top heater 5.
5 are connected in parallel, and a fuse 63 is connected to the input terminal of the rectifier 42 of the commercial power bus on the side to which the power switch 41 is not connected. In addition, the commercial power supply 20 includes:
A series circuit of a parallel circuit of the cooling fan motor 32, the primary winding of the power transformer 33, the primary winding of the power transformer 43, and the relay contact 31 is connected to the commercial power side of the power switch 21 and the power switch 41.

The output terminal of the rectifier 25 has a heating coil 27
a, a reverse conducting transistor 27c, a capacitor such as a resonance capacitor and a smoothing capacitor, and an inverter 27c including a circuit block 27b including a diode and a switching element. Similarly, the rectifier 4
The output terminal 2 is connected to a heating coil 47a, a reverse conducting transistor 47c, a capacitor such as a resonance capacitor and a smoothing capacitor, and an inverter 47 including a circuit block 47b including a diode and a switching element.

The secondary winding of the power transformer 22 is connected to the power circuit 2
3 is connected to the diode 2
4, the secondary winding of the power transformer 33 is connected to the power circuit 34, and the output DC voltage of about 12 V is supplied to the power circuit 59 via the diode 35. Is entered. The power supply circuit 59 uses a DC voltage of about 5 V output as a control voltage and outputs a zero volt detection circuit 2.
9, a heating unit control circuit 30, an operation unit control circuit 37, an input device 38 for inputting a command relating to a heating operation of the heating coil 27a, an input device 39 for inputting a command relating to the roaster heater 53 and the upper surface heater 55, a heating coil 47a.
The input device 40 is supplied to the input device 40, the display device 36, and the high temperature display circuit 60 for inputting a command regarding the high temperature display. Power transformer 43
Is connected to a power supply circuit 44, an output DC voltage of 20V is applied to a power supply circuit 64 and a heating unit control circuit 51, and an output DC voltage of 5V of the power supply circuit 64 is used as a zero volt pulse generation circuit as a control voltage. 46, which is supplied to the heating unit control circuit 51.

The heating unit control circuit 30 includes a microcomputer, and inputs a zero volt pulse from a zero volt detection circuit 29 using the common potential as the negative electrode of the rectifier 25 to which the emitter of the transistor 27c is connected.
To drive the base of the transistor 27c, the drive coil of the relay 31, and the high temperature display circuit 60, and perform serial communication with the operation unit control circuit 37. The heating unit control circuit 51 includes a microcomputer, and uses the common potential as a negative voltage of the rectifier 42 to which the emitter of the transistor 47c is connected, and the zero volt detection circuit 46.
, A temperature signal from the thermistor 45, and a base of the transistor 47c.
The relay 52 and the drive coil of the relay 54 are driven, and serial communication is performed between the operation unit control circuit 37 via the photocoupler 49 and the photocoupler 50.

The thermistor 26 and the thermistor 45 are pressed against the lower surface of a ceramic top plate 61 (which is divided into two sheets but one sheet in the figure) which covers the upper portions of the heating coil 27a, the heating coil 47a and the upper heater 55. The thermistor 57 is disposed near the upper surface heater to monitor the load and the temperature of the top plate, and the thermistor 56 is disposed near the roaster heater 53 or the heating chamber to monitor the temperature of the roaster heater 53 or the heating chamber. is there.

The operation of the heating cooker configured as described above will be described. When the linked power switch 21 and the power switch 41 are turned on, a commercial voltage is applied to the primary winding of the power transformer 22, and a rectified and smoothed 20 V DC voltage is generated at the output terminal of the power circuit 23. This 20 V DC voltage is directly supplied to the heating unit control circuit 37. The heating unit control circuit 37 configures a driving circuit using this voltage, drives the transistor 27c, and supplies the power to the power supply circuit 59 via the diode 24. Supplied,
The power supply circuit 59 reduces this voltage to 5 V and supplies it to the heating unit control circuit 30, the operation unit control circuit 37, and other circuit blocks.

Heating section control circuit 30 and operation section control circuit 37
The microcomputers are built in each of them, and perform serial communication of digital control signals at the same time as supplying a control power of 5V. The serial communication is synchronized with a pulse generated by the zero volt detection circuit 27 in order to avoid the influence of external noise, and transmits / receives one bit at a time near the zero point of the commercial power supply. The microcomputer of the operation section control circuit 37 transmits data to the heating section control circuit 30 and the microcomputer of the control section control circuit 30 transmits corresponding data to the operation section control circuit 37. The microcomputer checks whether the communication can be performed normally or the operation of the heating unit can be performed normally, and when an abnormality is found, the microcomputer 36 can display the abnormality on the display unit 36.

When a heating command for the heating coil 27a is input from the input device 38, the microcomputer of the operation section control circuit 37 sends a signal to the display circuit 36 to indicate that the power is being supplied and to indicate the display and the output set level. The microcomputer performs a display and transmits this command to the microcomputer of the control unit control circuit 30 by serial communication. The microcomputer of the control unit control circuit 30 outputs an on / off drive signal to the base of the transistor 27c,
A high-frequency current is generated in the resonance circuit 27b, a high-frequency current is supplied to the heating coil 27a, a high-frequency magnetic field is generated, and a zero-volt pulse output from the zero-volt detection circuit 29 is input to drive the driving coil of the relay 31. Drives near zero volts of commercial power to turn on contacts.

As a result, the load pan 28 placed above the heating coil 27a is heated, the fan motor 32 operates, and the commercial power supply voltage is applied to the primary windings of the power transformer 33 and the power transformer 43, so that the power circuit 12 to 34 output terminals
V DC voltage is output. However, at this point, since the power supply circuit 23 has already output a DC voltage of 20 V, a reverse voltage is applied to the diode 35 and the power supply circuit 3
The output of No. 4 is cut off.

The power supply circuit 44 outputs a DC voltage of 20 V, and supplies this voltage to the heating unit control circuit 51 to form a drive circuit to drive the base of the transistor 47c. Step down to DC 5V
To supply a control power supply voltage to the heating unit control circuit 51, the microcomputer of the heating unit control circuit 51 starts operating, checks input signals from the temperature sensor and the zero volt detection circuit, and controls the operation unit. Serial communication is started via the circuit 37, the photocoupler 49, and the photocoupler 50. The operation unit control circuit 37 identifies the incoming signal from the heating unit control circuit 51,
It is determined whether the control system related to the roaster heater 53 and the upper heater 55 is normal. If an abnormality is found in this determination result, abnormality processing such as displaying an abnormality on the display circuit 36 or prohibiting the heating operation is performed for the corresponding heating unit.

When the loading pot 28 is heated, the thermistor 2
Since the temperature of 6 rises and the resistance value decreases, the microcomputer of the heating unit control circuit 30 detects this, and changes the output by changing the on / off ratio of the transistor 27c when temperature control is necessary. In addition, a signal indicating that the top plate temperature is high is output to the high temperature display circuit 60 to display the signal.

When the power switch 21 and the power switch 41 are turned off during heating, the supply of the DC 20 V power from the power circuit 23 is cut off, but the supply of the DC 12 V power from the power circuit 34 is started. Therefore, the conduction state of the relay 31 is maintained, so that the supply of the DC 5 V power from the power supply circuit 59 is continued, the display by the high temperature display circuit 60 is continued until the top board temperature is reduced, and the operation of the fan motor 32 is further performed. Is continued, the speed at which the temperature of the top plate near the heating coil 27a decreases can be increased.

When the device is stopped, the input device 3
When the heating command of the roaster heater 53 is input from 9, the microcomputer of the operation section control circuit 37 sends a signal to the heating section control circuit 30 based on the signal from the input device 39 to turn on the relay 31 and to turn on the power transformer 43. A power supply voltage is applied to the primary winding, the power supply circuit 44 outputs 20 V, and the power supply circuit 64 outputs a 5 V voltage, and the microcomputer of the heating unit control circuit 51 operates to display the display circuit 36.
And a serial communication signal is sent to the control unit 51. If the serial communication signal from the heating unit control circuit 51 is received and there is no abnormality, the heating command is continuously output to the heating unit control circuit 51, and the heating unit control circuit 51
2 is driven to cause the roaster heater 53 to generate heat. The thermistor 56 detects the temperature in the vicinity of the roaster heater 53 or the temperature of the heating chamber, controls the temperature of the heating chamber, and controls the fan motor 3 after the power switch 41 is turned off.
It is determined whether the continuous operation of step 2 is necessary.

Even if the power switch 21 and the power switch 41 are turned off during cooking by the roaster heater 53, if the temperature of the thermistor 56, the thermistor 45 or the thermistor 57 is higher than a predetermined temperature, the heating unit control circuit 51 turns on the fan. The operation unit control circuit 37 converts the drive request signal of the motor 32 into a serial signal via the photocoupler 50.
, The operation section control circuit 37 transmits a command to continue the operation of the relay 31 to the heating section control circuit 30, and the outputs of the power supply circuit 44 and the power supply circuit 34 are not immediately shut off. The microcomputer continuously operates the fan motor 32 so that the temperature inside the cooker does not rise due to the high temperature of the roaster heater 53 and the heating chamber and the excess heat capacity, or the heating operation of the heating coil 47a or the upper heater 55. The high-temperature display circuit 60 is turned on or off so as not to cause a burn due to a rise in the plate temperature.
By continuously operating the fan motor 32, the heating coil 27a
Further, the speed at which the top plate temperature near the heating coil 47a and the upper surface heater 55 is reduced can be increased.

After the power switch 21 and the power switch 41 are turned off, the heating unit control circuit 51 detects the temperatures of the thermistors 45, 56, and 57, and determines whether or not the high-temperature display circuit 60 needs to be turned on, and whether the fan motor 32 is driven. Is transmitted to the operation unit control circuit 37 by serial communication, and the heating unit control circuit 30 detects the temperature of the thermistor 26,
Since the necessity of turning on the high temperature display circuit 60 is transmitted to the operation section control circuit 37, the microcomputer of the operation section control circuit 37 needs to turn on the high temperature display circuit 60 at a temperature higher than a predetermined level by at least one of these thermistors. If there is, or if it is necessary to drive the fan motor 32, the contact of the relay 31 is kept conductive; otherwise, the contact of the relay 31 is released, and the operation of the fan motor 32 and the power supply circuit 34 The input of the power supply circuit 44 is cut off.

The semiconductor components constituting the rectifier 25 and the inverter 27 have a high possibility of causing a short-circuit failure. In this case, the current fuse 62 is blown to prevent an excessive current from flowing through the power supply line. Since the current fuse 62 is connected to the load side from the power transformer 22, even if the current fuse 62 is blown, the power transformer 22 is not cut off and the microcomputer of the heating unit control circuit 30 can operate. Can be turned on, and cooking can be performed using the remaining heating units without any trouble. Therefore, it is possible to avoid a situation where all the heating units cannot be used.

As described above, according to the present embodiment, the power switch 21 for directly connecting or disconnecting the power from the inverter circuit 27 including the heating coil 27a is provided. By shutting off, the heating operation can be reliably stopped irrespective of the failure or runaway of the microcomputer. Also, the power switch 21
Before the power supply is turned on, power is not supplied to the power supply circuit 23, the power supply circuit 34, and the power supply circuit 44, and control power is not supplied to the microcomputers of the heating unit control circuit 30 and the operation unit control circuit 37. The power consumption can be reduced even when the power supply is connected to a commercial power supply, and the voltage application time to the electronic components can be minimized to extend the life of electronic components such as an electrolytic capacitor. At the start of the heating operation, the microcomputer of the heating unit control circuit 30 drives the relay 31 to apply power to the primary winding of the power transformer 33, and the power circuit 23 and the power circuit 34
Of the power supply circuit 3 during the heating operation, the power supply circuit 3 is turned off.
Since power is supplied from 4 to the heating unit control circuit 30, the heating unit control circuit 30 can continue to operate the relay 31 and continuously operate the heating unit control circuit 30. Then, after the heating unit control unit 30 performs a predetermined process, the driving of the relay 31 is stopped, and the power supply to the power supply circuit 34 and the power supply circuit 44 is cut off. Can be stopped.

The current fuse 62 is connected to the power transformer 2
2 is provided on the power supply line on the load side of the connection point between the primary winding and the power supply line, so that power can be supplied to the power supply circuit 34 even if the current fuse 62 is broken. When the power switch 21 is turned on, the relay 31 is turned on to apply power to the power transformer 43, and the remaining heating section, that is, the heating coil 47a and the roaster heater 5 are turned on.
3 and the upper surface heater 55 can be operated, so that it is possible to prevent all the heating sections from becoming unusable.

Further, since the output voltage of the power supply circuit 23 is made higher than the output voltage of the power supply circuit 34 and the OR output is made by the diode 24 and the diode 35, a reverse bias is applied to the diode 35 when the power supply circuit 23 outputs. The output current does not flow in the power supply circuit 34, and the output current of the power supply circuit 34 flows when the power switch 21 is off, and there is no need to supply a current for driving the transistor 27c or displaying a level. Therefore, the output current capacity of the power supply circuit 34 can be reduced to reduce the cost and size.

After the power switch 21 is turned off, the heating unit control circuit 30 receives control power from the power circuit 34, monitors the temperature of the top plate with the thermistor 26, and turns on the high temperature display circuit 60. When it is determined that the operation is no longer necessary, the contact of the relay 31 is turned off, the power supply to the power supply circuit 34 is cut off, the power consumption is reduced, and the voltage application time to the electronic components is reduced to a necessary minimum. Life can be extended.

Further, since the fan motor 32 is connected in parallel with the power supply circuit 34 and the power supply circuit 44 and in series with the contact of the relay 31, even after the power switch 21 is turned off, the thermistor 26, thermistor 56, It is possible to operate the fan motor for a predetermined time while monitoring the temperature of the thermistor 57 or measuring the time,
In addition, based on the monitored temperature result, the relay 31 is shut off to stop supplying power to the fan motor 32, thereby saving power consumption associated with the operation of the fan motor and minimizing the operation time of the fan motor. Thus, the life can be extended.

When the power switch 21 is turned on, the control power is also supplied to the zero volt detection circuit 29. The microcomputer of the heating unit control circuit 30 controls the relay 21 based on the output pulse of the zero volt detection circuit 29. The power can be supplied within a predetermined range of the zero point of the commercial power supply. As a result, the rush current level when the relay 31 is turned on can be suppressed, and the risk of welding can be reduced.

A power switch 41 interlocked with the power switch 21 can supply or cut off power to or from the heating unit including the rectifier 42 and the inverter 47 including the heating coil 47a, and the heating unit by the roaster heater 53 and the upper surface heater 55. However, the power supply to the power supply circuit 44 that supplies the control voltage to the heating unit control circuit 51 is turned on or off by using the relay 31 in common. The microcomputer of the heating unit control circuit 51 is operated for the specified time, and thereafter, the control power supply or the drive of the fan motor is shut off, thereby saving power consumption and extending the life of the electronic components and the fan motor.

The operation section control circuit 37 and the heating section control circuit 30 perform direct serial communication with each other.
7 and the heating unit control circuit 51 perform serial communication with each other via a photocoupler, and supply control power for the operation unit control circuit 37 and the heating unit control circuit 30 from the power supply circuit 23 to reduce the negative potential of the rectifier 25. A common electric potential of the operation part control circuit 37 for inputting a control command and displaying an output level or the like to the heating part control circuit 30 for setting the common potential to the heating part control circuit 30 and the heating part control circuit 51 for setting the negative potential of the rectifier 42 to the common potential. Can be unified to the common potential of the heating unit control circuit 30, so that the operation unit control circuit 37 can be compressed and downsized and simplified. In addition, by turning on the operation unit power switch 21, the operation unit control circuit 37 The control power is supplied from the power supply circuit 34, and the microcomputer becomes operable.
The user can promptly receive and output a heating command regarding the heating coil 47a, the roaster heater 53, and the upper surface heater 55 without time delay by communication. Can be avoided.

After the power switch 21 is turned on, a heating command for one of the heating coil 27a, the heating coil 47a, the roaster heater 53, and the top heater 55 is sent from the input device 38, the input device 39, or the input device 40. When input, the relay 31 is turned on to supply power to the power supply circuit 34, the power supply circuit 44, and the fan motor 32, so that power consumption can be saved and the life of electronic components and the fan motor can be extended.

In the above embodiment, the power switch 21
, After the heating coil 27a, the heating coil 47a,
The heating command for either the roaster heater 53 or the top heater 55 is input to the input device 38 or the input device 3.
9 or input from the input device 40, the relay 31 is turned on, and the power supply circuit 34, the power supply circuit 44 and the fan motor 3
However, when the power is supplied to the heating unit control circuit 30 after the power switch 21 is turned on, the microcomputer of the heating unit control circuit 30 immediately turns on the relay 31 and turns on the fan. Motor 32 and control power supply 33
Power may be supplied to the control power supply 34. The reliability can be improved by controlling the closing phase of the relay 31. If the heating command is not input for a predetermined time, the relay 31
Is turned off, and the relay 31 is turned on at the time when the heating command is received again, it is possible to obtain the effect of saving power consumption and extending the life of parts such as the fan motor.

In the above embodiment, a parallel circuit of the power transformer 33, the power transformer 43, the fan motor 32, and the relay 31 are connected in series, and all the above-mentioned power-on or power-off is simultaneously performed by turning the relay 31 on and off. Although the circuit has been simplified, the present invention is not limited to this configuration. By connecting at least the primary winding of the power supply circuit 33 and the relay 31, the heating unit control circuit 30 after the power switch 21 is turned off.
In addition, it is possible to obtain an effect of reducing the power consumption and prolonging the life of the parts, and to connect at least the fan motor 32 and the relay 31 and to control commands such as a heating command for a predetermined time. Is not input, the relay 31 is turned off, and after that, the relay 31 is turned on after the heating command is input, so that the power required for driving the fan motor is saved and the life of the fan motor is reduced. Can be obtained.

In the above embodiment, the operation unit control circuit 37 is used.
And the heating unit control circuit 30 are separated from each other to perform serial communication. However, the present invention is not limited to this, and both are configured as an integrated heating control unit, and the same effects as some of the effects described above are obtained. The effect can be obtained.

In the above embodiment, the output of the power supply circuit 23 and the output of the power supply circuit 34 are OR-connected to increase the output voltage of the power supply circuit 23. Is applied to apply a reverse voltage to cut off the output of the power supply circuit 34. However, the means for cutting off the output is not limited to this, and a new switching element may be added to cut off the output. Oscillation may be stopped if a switching power supply or the like is used.
Alternatively, the power supply circuit 23 and the power supply circuit 34 may be operated at the same time so that one of the circuits can compensate for the shortage of the control capacity during the heating operation.

[0047]

According to the first aspect of the present invention, the first switching means for turning on or off the power of the heating unit can reliably stop the heating operation regardless of the failure or malfunction of the heating control unit. And, after the power supply of the heating unit is cut off by the first switch means, the heating control unit is operated to a necessary minimum by the second control power supply path, and finally, the heating control unit is turned on by the second switch means. By shutting off the power supply, a heating cooker with low power consumption and a long product life can be provided.

When the control command for the heating section is not input, the power supply to the second control power supply path by the second switch is stopped, and the control command is not input thereafter. Waiting, the power supply to the second control power supply path by the second switch means is performed, thereby suppressing power consumption after the second switch means is supplied to the second control power supply path, and The effect is obtained that a heating cooker with a long life can be provided.

According to the second aspect of the present invention, the fan motor is efficiently driven after the power supply to the fan motor by the second switch means, so that the drive time of the fan motor is shortened and the life is extended. In addition, it is possible to provide a heating cooker that consumes less power due to the driving of the second switch means and the driving of the fan motor.

According to the third aspect of the present invention, at least the operation of the fan motor after the start of heating cooking, the operation of the fan motor after the heating cooking, and the high temperature display function of the top plate temperature can be further achieved. The effect is obtained that it is possible to provide a heating cooker that can suppress and shorten the operation time of the fan motor and the power supply circuit to extend the life.

According to the fourth aspect of the present invention, the voltage application time of the fan motor or the electronic component is minimized, and the first
Power consumption by the switch means is further reduced, and the life of the fan motor or electronic parts is reduced.
The effect of being able to provide a heating cooker that can be made longer can be obtained.

[Brief description of the drawings]

FIG. 1 is a circuit block diagram of a heating cooker according to a first embodiment of the present invention.

FIG. 2 is a circuit block diagram of a conventional heating cooker.

[Explanation of symbols]

Reference Signs List 21 power switch (first switch means) 22 power transformer (first control power supply) 23 power supply circuit (first control power supply) 24, 35 diode 26 thermistor (temperature detection unit) 27 inverter (heating unit) 29 zero volt Detecting means 30 Heating section control circuit (heating control section, first heating control section) 31 Relay (second switch means) 32 Fan motor 33 Power transformer (second control power supply) 34 Power supply circuit (second control power supply) 37) operation part control circuit (heating control part, operation control part) 41 power switch (other switch means interlocked with the first switch means) 43 power transformer (control power supply of another heating control part) 44 power supply circuit (others) 45 Thermistor (Temperature detecting unit) 46 Zero volt detecting means 47 Inverter (Other heating unit) 49, 50 Photo Plastic 51 heating unit control circuit (the other heating control unit) 53 roaster heater (other heating portion) 55 top heater (other heating unit) 56, 57 thermistor (temperature detecting unit)

Claims (4)

[Claims] 1. A heating unit, a heating control unit for controlling a heating operation of the heating unit, a first switch for turning on or off the power of the heating unit, and a power for being turned on or off by the first switch. A first control power supply path for supplying control power of the heating control unit, and a second switch means for supplying power to the heating unit and the first control power supply path by the first switch means. The power supply to the control power supply path is performed. If the control command of the heating unit is not input for a predetermined time, the power supply to the second control power supply path by the second switch unit is released, and thereafter, the control power supply to the control power supply path is stopped. A heating cooker which waits until a control command is input and supplies power to the second control power supply path by the second switch means. A first switch means for turning on or off a power supply to the heating unit; and a second switch means for turning on or off a power supply to the fan motor for cooling. After the power to the heating unit is turned on by the switch means, the power to the fan motor is turned on by the second switch means, and if no control command is input for a predetermined time, the power supply to the fan motor by the second switch means is released, A heating cooker configured to wait until a control command is input thereafter, and then turn on power to the fan motor by the second switch means. 3. The heating command according to claim 1, wherein the control command is a heating command.
Or the heating cooker according to claim 2. 4. After the power is turned on by the first switch means,
The configuration according to any one of claims 1 to 3, wherein the second switch means is controlled to supply power to the second control power supply path or the fan motor in connection with the start of the heating operation of the heating unit. Cooking cooker.