JP2003223983A - Electric equipment - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an electric equipment having low power consumption by reducing the power supply in a circuit system when not in use such as waiting. <P>SOLUTION: The electric equipment is provided with a load RL, a control means 9 to drive and control the load RL, and power supply circuits 1 to 6 to supply electric power to the control means 9. The control means 9 has a normal mode in which the electric power is supplied to the load RL, and a power saving mode in which the electric power supply to the load RL is restricted, and the normal mode and the power saving mode are changed according to a prescribed condition. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an electric device such as a microwave oven.

[0002]

2. Description of the Related Art In a conventional electric device such as a microwave oven, when a plug is inserted into a power outlet, the power transformer and the operation control circuit are always connected to the electric transformer even when not being used for cooking. Since the power supply voltage is applied, the power supply current is supplied to the CPU, various sensors, the display tube and the like in the internal control circuit through the power supply transformer.

[0003]

Therefore, in the microwave oven having the above circuit configuration, the electric current is always supplied to the power transformer and the operation control circuit even when the microwave oven is not used for cooking and is in the operation standby state. There is a drawback that a loss such as a loss and a copper loss occurs, and a circuit system such as a CPU consumes electric power of about 10 W.

The present invention has been made in view of the above problems, and reduces electric power consumption to the circuit system by reducing the electric power supply to the circuit system when the electric equipment is not used such as during standby. Intended to provide equipment.

[0005]

In order to achieve the above object, in the first configuration of the present invention, a load, control means for driving and controlling the load, and a power supply circuit for supplying electric power to the load and the control means. In the electric device including, the control means has a normal operation mode for supplying rated power to the load, and a power saving mode for limiting power supply to the load, and the normal operation mode or I am trying to set the power saving mode.

In such a structure, for example, in the case of a microwave oven, the power supply to the load such as a magnetron is controlled by using a relay whose opening and closing is controlled by the control means. In addition, the electric device supplies power to a display unit that displays a screen in the normal operation mode. On the other hand, if there is no key operation input to the electric equipment and it is in standby,
The control means stops the power supply to, for example, the display unit. This saves electricity in the electric device.

In the second structure of the present invention, the first
In the above configuration, the normal operation mode is automatically set while the cooking menu selection screen of the heating cooker is displayed. This prevents the display from disappearing while the cooking menu is selected.

In the third structure of the present invention, the first
In the configuration, the power supply circuit includes a rectifier circuit that rectifies an AC power source, a load smoothing capacitor that smoothes an output of the rectifier circuit and supplies power to the load, the load and the load in the power saving mode. Switch means for limiting the power supply to the smoothing capacitor.

According to such a construction, the electric equipment converts the AC power source such as the commercial power source into the direct current by the rectifier circuit such as the diode bridge, smoothes it by the load smoothing capacitor, and then the load such as the relay and the display section and the CPU. Power is supplied to the operating power supply circuit. Then, for example, a transistor that performs a switch operation is inserted so as to be in series with the load smoothing capacitor, and by controlling the transistor to be turned on / off by the control means, the DC voltage from the rectifier circuit is applied to the load smoothing capacitor. It has control of supplying. In the power saving mode, the electric device cuts off the power supply to the load smoothing capacitor by the control means and stops the power supply to various circuit loads such as the relay and the display unit. As a result, it is possible to cut wasteful power consumption due to energizing the large-capacity load capacitor and power consumption due to load energization.

According to the fourth aspect of the present invention, the first
In the above configuration, the control means has a plurality of processing items, and the execution processing items are reduced in the power saving mode.

As items to be processed by the control means, for example, in a microwave oven, an item for collecting and analyzing the signal from the absolute humidity sensor for the food heating condition, and a signal is output to the display unit or the like based on the analysis result. There are items to do and items to take in key input from the operation panel. In the normal operation mode, these items are processed in a predetermined order based on the zero cross point of the commercial power source in consideration of the influence of noise due to the magnetron oscillation. On the other hand, in the power saving mode, for example, analysis and display are unnecessary, so that processing items can be omitted and the processing of the control unit can be lightened to reduce power consumption.

According to the fifth aspect of the present invention, the above-mentioned third aspect is used.
In the configuration of, the electric device is a heating cooker,
A circuit for supplying a minute current is provided to the humidity sensor using a self-heating type heating element whose power supply is limited by the switch means.

In such a configuration, the electric device keeps the idling temperature by passing a minute current through the humidity sensor using the self-heating type heating element in the power saving mode.
The operation of the sensor can be stabilized early when returning to the normal operation mode.

Further, in the sixth aspect of the present invention, the above first
In the above configuration, a display for manually setting the power saving mode is provided on the menu selection screen, and the control means sets the power saving mode by selecting the display.

With such a configuration, the power saving mode can be manually set using the menu selection screen. That is,
While viewing this display, the user can change the mode setting by operating the menu screen, for example.

In the seventh structure of the present invention, a load and
In an electric device including a control unit that drives and controls the load, and a power supply circuit that supplies power to the control unit, a first switch that controls power supply to the control unit, and the first switch. A second switch connected in parallel, wherein the control means controls the second switch which is turned on by receiving the electric power from the first switch.

In such a structure, in the case of a microwave oven as an electric device, for example, the first switch is turned on / off according to opening / closing of the door, and is turned on when the door is opened and turned off when the door is closed. When the first switch is turned on by opening the door, the microwave oven turns on the second switch by the holding circuit or the control means. After that, even if the user closes the door, the power supply is continued because the second switch is on. Then, after the operation such as heating is performed, if the microwave oven is in a standby state, the control means turns off the second switch. When the door is opened again, the first switch is turned on, and the operation is restored.

According to the eighth aspect of the present invention, there is provided the above seventh aspect.
In the above configuration, a single-throw two-pole three-terminal switch is adopted as the first switch, one of the two poles is connected to a power supply circuit, and the other is connected to an input circuit to the control means,
The first switch serves as an input unit to the control unit after the second switch is turned on.

In such a structure, the first switch is a three-terminal switch, and the other terminal of this switch is connected to the photocoupler. Then, the output of the photocoupler is input to the control means. Accordingly, the first switch and the switch for turning on the power can be used also as the input key for canceling the control means after turning on the power and giving an instruction such as stop.

Further, in the ninth structure of the present invention, in the seventh structure, a latching relay for holding an on / off state is adopted as the second switch.

According to this structure, the latching relay remains closed during operation, even if the supply of power is interrupted due to a drop in the power supply voltage, such as when the power plug of the electric device is disconnected from the outlet. . As a result, when the power plug is turned on again, commercial power is supplied to each part such as the control means without turning on the first switch, and the electric device is immediately restored.

According to a tenth structure of the present invention, in the seventh structure, the control means turns off the second switch when the power supply voltage is not within a predetermined range. ing.

According to this structure, the electric device takes in the power supply voltage into the control means. For example, the commercial power source is 2
When the voltage is outside the specified range, such as 00V,
The control means immediately turns off the second switch to prevent the electric device from operating.

[0024]

BEST MODE FOR CARRYING OUT THE INVENTION <First Embodiment> A first embodiment in which the present invention is applied to a microwave oven will be described. FIG. 1 is an electric circuit diagram of a microwave oven provided with a low power consumption circuit during operation standby according to the present invention. In FIG. 1, 1
Is a plug to the commercial power source, and 2 is an outlet insertion determination circuit that determines the insertion states of the insertion plug and the outlet.

Reference numeral 3 is a power transformer, which lowers the voltage of the commercial power source taken from the power plug 1. Reference numeral 4 denotes a full-wave rectification circuit, which is composed of, for example, a diode bridge. The direct-current voltage that is full-wave rectified by the full-wave rectifier circuit 4 becomes a stable direct-current voltage by the CPU operation power supply circuit 6 and is supplied to the CPU 9. This DC voltage is input to the port (VCC) of the CPU 9 on the high voltage side and to the port (VSS) on the low voltage side.

Reference numeral 5 denotes a power saving operation control circuit, which is a CPU 9
The power supply to various circuit loads provided in the microwave oven is controlled according to a signal from the port (PD) of the. Although the operation panel 10 is illustrated as a representative of the various circuit loads, there are other cooking information detection circuits, relay circuits, and the like, which are not illustrated. This relay circuit is used to control the power supply to the magnetron (not shown). The operation panel receives a signal from the CPU 9 to display the screen display section 19
The cooking menu or the like is displayed with, and signals from the rotary knob 16 and the operation keys 17 and 18 are transmitted to the CPU 9. The above circuits 1 to 6 are power supply circuits.

Reference numeral 7 denotes an AH sensor minute current circuit, which is an AH sensor (absolute humidity sensor) R of a microwave oven.
A and a resistor R2 that supplies a minute current to the AH sensor RA
And a smoothing capacitor C3. Reference numeral 8 denotes a power supply synchronization signal generation circuit, which detects a zero-cross point of the AC power input from the power plug 1 from the input side of the full-wave rectification circuit 4 and outputs a signal synchronized with the zero-cross point to the CPU 9. Reference numeral 11 is a mode switching key connected to the input / output ports (KS, Ki) of the CPU 9. The port (K
i) is connected to a line having a voltage equal to that of the port (Vss) via a resistor R12 in order to equalize the voltages.

The CPU 9 is a control means for performing arithmetic processing and operates by supplying power from the CPU operating power supply circuit 6 to the ports (Vcc) and (Vss). CP
A switch SW) is provided inside U9 and is turned on in the normal operation mode to set the output of the port (PD) to a high level, while in the power saving mode, the switch SW) is provided.
Turn off P to low level.

The above-mentioned parts will be described in more detail. CP
In the U operation power supply circuit 6, the high-voltage side of the DC voltage that is full-wave rectified by the full-wave rectification circuit 4 is a rectification diode D5.
Also, it is connected to one end of the smoothing capacitor C2 via the current limiting resistor R1. The other end of the smoothing capacitor C2 is connected to the low voltage side of the full wave rectifier circuit 4. As a result, the full-wave rectified DC voltage is smoothed, further stabilized by the regulator IC (Integrated Circuit) 15, and supplied to the CPU 9.

The capacitor C4 connected to the output side of the regulator IC15 is
This is to improve the transient characteristics due to the load fluctuation on the output side of. As described above, the power supply to the CPU 9 is controlled by the series drop power supply method using the regulator IC 15 to suppress the power loss.

In the power saving operation control circuit 5, the base of the NPN transistor Q1 is connected to the CPU 9 via the resistor R3.
Of the transistor Q1
Is connected to the base and the emitter of the resistor through a resistor R4. The collector of the transistor Q1 is connected to the high voltage side of the full-wave rectification circuit 4 via resistors R5 and R6 connected in series with the transistor Q1. The connection midpoint of the resistors R5 and R6 is connected to the base of the PNP transistor Q2.

The transistor Q2 has an emitter connected to the high voltage side and a collector connected to one end of the load smoothing capacitor C1. The other end of the capacitor C1 is connected to the low voltage side of the full-wave rectifier circuit 4. When a high level signal is output from the port (PD) of the CPU 9, the transistors Q1 and Q2 are turned on, so that the smoothing capacitor C1 smoothes the full-wave rectified DC voltage and supplies power to various circuit loads RL. do.

On the other hand, when a low level signal is output from the port (PD), the transistors Q1 and Q2 are turned off, so that the diode D8 connected in the opposite direction disconnects the load capacitor C1 from the full-wave rectifier circuit 4. In addition, the power supply to the various circuit loads RL is cut off.

In the AH sensor micro-current circuit 7, the full-wave rectified voltage from the full-wave rectifier circuit 4 is smoothed by the smoothing capacitor C3 via the current limiting resistor R2.
A minute current is being supplied to. AH sensor RA is 2
One of the self-heating type thermistors is a sealed type and the other is an open type. By keeping both elements stable at about 150 ° C, the humidity is detected by the resistance value of both thermistors. . The cooking information detection circuit (not shown) described above is a circuit that detects steam generated from food or the like by heating the microwave oven based on a signal from the AH sensor RA.

The reason why the AH sensor minute current circuit 7 and the power saving operation control circuit 5 are connected by the resistor R11 is to achieve stable operation in the normal operation mode.

In the power saving mode, the capacitor C1 is turned off, but the resistor R2 provided separately from the circuit 5 is used.
Also, a minute current is supplied to the AH sensor RA by the smoothing capacitor C3, and the AH sensor RA maintains the idling temperature. As a result, the power consumption of the AH sensor RA is reduced in the power saving mode, and the operation of the AH sensor RA is quickly stabilized when the power saving mode returns to the normal operation mode.

In the power supply synchronization signal generation circuit 8, the AC voltage is divided from the input side of the power supply transformer 4 by the resistors R7 and R8, and is input to the base of the NPN transistor Q3. Further, a bypass capacitor C5 for releasing noise and the like is connected between the base and the emitter of the transistor Q3.

The collector of the transistor Q3 is connected to the high voltage output side of the regulator IC15 via the resistor R9, and further, the capacitor C6 is connected in parallel with the resistor R9 for improving the transient characteristics. As a result, the transistor Q3 is turned on / off in synchronization with the commercial power source, and the zero cross point is detected. This detection result is input as a trigger from the collector side of the transistor Q3 to the interrupt port (INT) of the CPU 9.

As described above, the CPU 9 is provided with the input / output ports (Ki, KS). A request signal is output from the port (KS) through the diode D9, and the port (Ki) receives the request signal.

When the switching key 11 is turned on,
The request signal output from the port (KS) is directly input to the port (Ki). On the other hand, when the switching key 11 is off, the request signal cannot be received at the port (Ki). Using this, the CPU 9 can determine whether or not the power saving mode operates effectively. For example, when the switching key 11 is open, the power saving mode is enabled, and when it is closed, the power saving mode is not entered.

The port (INT) receives a trigger signal from the power supply synchronizing signal generating circuit 8. Furthermore, CPU
9 inputs and outputs signals to and from the operation panel and cooking information detection circuit (not shown). When a trigger signal is input to the port (INT), the CPU 9 sends a request signal to the port (KS)
Send out and request signal from port (Ki)
After the check is completed, in the case of the power saving mode, the internal processing operation of the CPU 9 is switched to the power saving mode.

The plug-in determination circuit 2 is provided between the power plug 1 and the power transformer 3, and diodes D6 and D7 for preventing reverse voltage are connected to both ends of the power plug 1 so that their cathodes face each other in series. A current limiting resistor R10 and a light emitting diode LD are connected in series so as to be in parallel with the diode D7. As a result, when the power plug 1 is inserted into the outlet and power is supplied, the light emitting diode L
D emits light.

Since the outlet plug-in determination circuit 2 can know the plugged state of the power plug 1 by the light emission of the light emitting diode LD, attention should be paid to a person who repairs the plugged state of the power plug 1 when repairing a microwave oven or the like. Can be evoked, and electric shock, etc. can be prevented.

The operation panel 10 shows the inserted state.
Although it is possible to display the screen on the display unit 19 in the above, when repairing in a state where the display is turned off due to a failure of the microwave oven, even if the person who repairs looks at the display unit 19, the power supply is turned on. It is impossible to judge whether or not is included. On the other hand, unlike the present embodiment, the insertion state is directly notified without the processing of the CPU 9 or the like, which is excellent in safety.

Next, the processing of the CPU 9 of this embodiment will be described. FIG. 2 is a flowchart showing the processing. When the insertion plug 1 is inserted into the outlet of the power source, the power is supplied to each circuit of the microwave oven to start the processing. First, the CPU 9 performs key input processing of signals from the rotary knob 16 and the set key 17 in the input step S10.

Then, in step S15, the heating key 18
It is determined whether or not there is a heating instruction by. If there is an instruction, heating control is performed in step S20 in accordance with conditions such as the heating time set in the cooking menu or the like. Then, after the heating control is completed, the process proceeds to step S25. On the other hand, if there is no heating instruction in step S15, step S15
Go directly to 25. The heating control includes a sensor after the heating operation and a cooling operation control of the high temperature part.

In step S25, the CPU 9 determines whether or not the power saving mode is set by looking at the request signal at the port (KS, Ki). If not in the power saving mode, the process returns to step S10. On the other hand, if it is in the power saving mode, the process proceeds to step S30 and the CPU
9 outputs a high-level signal instructing power down from the port (PD). As a result, the power saving operation control circuit 5 stops the power supply to the various circuit loads RL of the operation panel 10.

After that, when a trigger representing the zero cross point of the commercial power source is input to the port (INT) of the CPU 9 (step S35), the normal operation recovery waiting process of step S40 is performed. In this process, the signal from the operation panel 10 is read to determine the presence / absence of a key input. Then, when there is a key input to return to the normal operation mode, the process returns to step S10. On the other hand, when there is no key input and the normal operation mode is not restored, the power saving mode (step S50) is continued and the process returns to step S35.

CPU in power saving mode and normal operation mode
FIG. 3 shows the difference in processing in No. 9. C is shown in FIG.
The trigger signal input into the port (INT) of PU9 is shown. As described above, this signal is a signal of a constant cycle synchronized with the zero cross point of the commercial power source. FIG. 3B shows an operating state of the CPU 9 in the power saving mode.

When the trigger signal is input at time t1, in the power saving mode, the CPU 9 performs a key input operation process as shown by 20, and determines from a signal such as a door opening or a key input operation. At this time, when there is no input operation and the normal operation mode is not restored, the CPU 9 does not perform any other processing, and waits until the next trigger signal is input. Then, the same processing is repeated until the normal operation mode is restored.

FIG. 3C shows the processing operation of the CPU 9 in the normal operation mode. When the trigger is input at time t1, first, in the period shown at 21, the above-mentioned cooking information detection circuit (not shown) detects and analyzes the information from the AH sensor RA or the like. Next, in a period indicated by 22, a signal is output to the display circuit 19 and the like of the operation panel 10 based on the analysis result and the like. Then, in the period indicated by 23, the key operation input signal is input and the operation is stopped. And
The above operation is repeated each time a trigger is input unless the mode is changed to the power saving mode.

The reason why the processing items are divided into some and the processing is performed based on the trigger is that the noise due to the oscillation of the magnetron (not shown) is small when the commercial power source is near the zero cross point. This is because it takes into consideration that In other words, in order to reduce the influence of noise, information from various sensors is analyzed near the zero cross point of the commercial power source, and then signals such as screen display are output in that order.

In the embodiment described above, the mode is switched by the specially provided switching key 11 (see FIG. 1), but even if the mode is set to be always the power saving mode without switching. Good. Further, the mode setting may be performed by the method described below.

That is, when the use of the microwave oven is started, the time is set on the initial setting screen, but at this time, the power saving mode is set. FIG. 4 shows an example of a display screen on the display unit 19. FIG. 4A shows a screen state when the initial setting screen is displayed. At this time, the rotary knob 16
Since the cursor moves by turning, select "Power saving / Clock" and press the set key 17.

As a result, the screen becomes the power saving setting screen as shown in FIG. 4 (b). Then, the cursor is moved by turning the rotary knob 16, and the power saving mode is set by selecting "OFF (power saving)" shown by 50 and pressing the set key 17. As a result, the screen display is turned off when the microwave oven enters the power saving state.

When "Menu" shown in 51 is selected while the microwave oven is on standby, a menu screen as shown in FIG. 5 is displayed and the normal operation mode is set. Also,
When the "clock" shown in 52 is selected, the current time is displayed and the normal operation mode is set.

In this way, the power saving mode can be set. Further, also in the cooking menu screen used when setting the food to be cooked in the microwave oven and the heating time, it is possible to set the power saving mode by selecting "power saving" by rotating the rotary knob 16 as shown in FIG. .

As described above, according to this embodiment,
When the operation processing is in the power saving mode while the microwave oven is on standby, various loads RL other than the CPU 9 and the AH sensor RA
Since no power is supplied to the device, power consumption is reduced. Further, as shown in FIG. 2, in the present embodiment, since the judgment using the timer or the like is not made to shift to the power saving mode, the user mistakes the key input due to the backlight of the display screen. There is no problem. In addition, although the microwave oven is described as an example in the present embodiment,
Even in various other electric devices, the power consumption can be reduced by shifting to the power saving mode when it is in a standby state.

<Second Embodiment> A second embodiment of the present invention will be described with reference to FIGS. 6 and 7. In this embodiment, a DC voltage is generated from an AC power source such as a microwave oven to operate the CPU 38 or the like which is a control means. In FIG. 6, the power plug 31 is inserted into an outlet and the switch SW1 is turned on to supply commercial power to the primary winding 41 of the power transformer 32.

In the case of a microwave oven, the switch SW1 is a switch which operates in conjunction with opening and closing of the door, and is turned on when the door is open and turned off when the door is closed. The switch SW1 may be a power switch that operates manually, but in that case, the switch SW1 is turned on while being pressed by the user and turned off when the user's hand is released.

When commercial power is supplied to the primary winding 41 of the power transformer 32, the reduced voltage is output from the secondary winding 42. This is rectified by a full-wave rectifier 34 composed of a diode bridge or the like. Then, it is smoothed by the smoothing capacitor 35, divided by the resistors R1 and R2,
N whose base is connected to the connection midpoint of the resistors R1 and R2
The PN transistor Q1 is turned on.

Since the relay coil 45 is connected in series to the collector side of the transistor Q1, when the transistor Q1 is turned on, a current is supplied to the relay coil 45. As a result, the relay contact RY1 is closed, so that commercial power is always supplied to the power transformer 32 regardless of whether the switch SW1 is opened or closed.

The DC voltage smoothed by the capacitor 35 is supplied to the load driving relay 36 and the like. The load driving relay 36 controls power supply to a heating magnetron (not shown). Also, the capacitor 35
The voltage smoothed by is stabilized by the three-terminal regulator 37 and supplied to the CPU 38.

The CPU 38 can turn off the transistor Q1 by outputting a low level signal S1 to the base of the transistor Q1. Therefore, during standby of the microwave oven, if the CPU 38 turns off the relay RY1 while the switch SW1 is off, commercial power is not input to the power transformer 32, so that current does not flow in the circuit and is consumed. The power can be 0W.

The voltage smoothed by the capacitor 35 is divided by the resistors R3 and R4 and input to the CPU 38. As a result, the CPU 38 can determine whether the power supply voltage is normal by AD conversion or the like. For example, it is safe because the relay RY1 can be immediately turned off when the product is mistakenly connected to the 200V power supply although the power supply is 100V.

Power is supplied by the above DC voltage, and the CPU
One of the circuits controlled by 38 is, for example, the operation panel 55. The operation panel 55 is provided with a time display portion 57 for displaying the time, a heating start key 56, a mode switching key 58 for switching the mode to be described later, and the like.

The operation will be described below with reference to FIG. 7 showing the control flow of the CPU 38. First, the user inserts the plug 31 into the power outlet. Step K5
When the door is opened, the relay coil 45 is energized and the relay contact RY1 is turned on as described above (step K1).
0). As a result, even if the door is closed and the switch SW1 is turned off thereafter, the power transformer 32 is relayed via the relay contact RY1.
Since the power is supplied to the CPU, the supply of the power supply voltage to the CPU 38 and the like can be maintained.

Next, in step K15, it is determined whether or not the standby power saving mode is set by the switch key 58. When the standby power saving mode is set, the process proceeds to step K20, and it is determined whether or not a predetermined time (for example, 1 minute) by the built-in timer of the CPU 38 has elapsed, and if it has elapsed, the process proceeds to step K45. Then, the relay RY1 contact is turned off. The relay contact RY1 is turned off by the CPU.
38 is realized by turning off the transistor Q1 by setting the drive signal S1 to the low level.

If the predetermined time has not elapsed in step K20, the process proceeds to step K25, in which the heating condition is instructed (this instruction is given by the heating key 56).
Wait for Then, in step K30, it is determined whether or not there is a heating start instruction, and if there is, a relay 36 is operated to control heating (step K35). If there is no instruction, the process returns to step K20. When heating is controlled in step K35 and heating is completed in step K40, step K4
Go to 5 and turn off relay RY1.

When the standby power saving mode is not set in step K15, the routine of steps K50 to K75 (normal operation mode routine) is executed, and the process returns to step K15. The point that this routine is remarkably different from the power saving mode routines (K20 to K40) is the time display unit 57.
The point is that the time is displayed (step K55), and that the step K15 is executed after the last step K75 is executed.

In the above embodiment, the relay RY1 contact may be formed by a semiconductor switch circuit. In that case, the relay coil 45 becomes unnecessary. When the magnetron (not shown) and the power source of the CPU 38 are separate power sources, a battery may be used as the power source of the CPU 38.

As described above, according to this embodiment,
After a lapse of a certain time after the heating control is completed, the relay RY1 contact is turned off in the standby mode, so that the power consumption of the circuit network shown in FIG. The present invention can be applied to various electric devices by changing the configurations of the relay 36 and the operation panel 55.

<Third Embodiment> A third embodiment of the present invention will be described with reference to FIG. In this embodiment, the switch SW2 inserted between the power plug 31 and the primary winding does not perform a simple opening / closing operation, but is normally closed (hereinafter referred to as “NC”) or normally open (hereinafter referred to as “NO”). 3) configuration and common (hereinafter referred to as “C”). In the case of the microwave,
The connection is changed to NC and NO according to the normal opening and closing of the door. Normally, the door is in the NC state, and the power supply to the power transformer 32 can be controlled by opening / closing the relay RY1.

When the switch SW2 is connected to the NC terminal, a current flows to the light emitting diode 43 side of the photocoupler PT1 via the current limiting resistor R5, so that the transistor 44 of the photocoupler PT1 is turned on. This allows
A low level signal from the photo coupler PT1 is sent to the CPU 38a.
Is output to. On the other hand, when the switch SW2 is connected to the NO terminal, no current flows through the resistor R5 and the transistor 44 is turned off, so that a high-level signal is generated by the power supply voltage connected via the pull-up resistor R6. It is input to the CPU 38a.

As a result, the switch SW2 can serve both as a power switch and an input switch (for example, a cancel key) in the power-on state. Note that FIG.
In other respects, the other parts are the same as those in the second embodiment, and the same parts as those in FIG.

<Fourth Embodiment> A fourth embodiment of the present invention will be described with reference to FIG. Switch SW1 inserted between the power plug 31 and the power transformer 32
About this Latching relay RY to be in parallel
2 is connected. Latching relay RY
In the configuration No. 2, for example, a set coil 60 and a reset coil 61 are provided inside, and the contact of the relay RY2 is set to a high level for a short period with respect to the switch 47 of the set coil 60 as shown in FIG. When the switch 48 of the reset coil 61 is closed and is set to the high level for a short period of time, the contact of the relay RY2 is opened.

By utilizing the latching relay RY2 having such characteristics, the relay RY2 can be closed in the initial setting of the electric device. With this configuration, electric power is immediately supplied to the primary winding 41 when the power plug 2 is connected to the outlet, and the electric device can be operated immediately.

In this embodiment, as in the second embodiment, the relay RY2 is opened in the standby state to reduce the power consumption. Further, the voltage divided by the resistors R7 and R8 is input to the CPU 38b across one end of the secondary winding 42 and the ground side of the DC voltage smoothed by the full-wave rectification circuit 34 and the capacitor 35. Since the relay RY2 is in the closed state when the power plug is unplugged during operation or when there is a power failure, immediately when the power plug 31 is plugged in again or when the power is restored from the power failure. Power is sent to the power transformer 32, and the CPU 38b and the like can be operated.

In the second embodiment (FIG. 6), it is necessary to connect the power plug 31 to the outlet and then turn on the power switch SW1 in order to drive the electric equipment. If the power plug 31 is connected to an outlet, it can be driven immediately. Also,
During standby, the CPU 38 opens and closes the latching relay RY2.
Since it is controlled by b, the power consumption becomes 0W. Other parts are the same as those in the second embodiment, and therefore, the same parts as those in FIG.

[0080]

<Effect of claim 1> After the operation in the normal operation mode is completed, the power saving mode is set to limit the power supply to the load such as the magnetron, so that the power consumption of the electric device in the standby mode is reduced. You can

<Effect of Claim 2> Since the normal mode is automatically set while the selection screen of the heating cooker is displayed, the display does not disappear during selection of the cooking menu. for that reason,
There is no problem that the user makes a mistake in key input.

<Effect of Claim 3> When a DC voltage is obtained by rectifying an AC power supply and smoothing it with a load smoothing capacitor, the load smoothing capacitor should not be operated in the power saving mode. Because
It is possible to cut wasteful power consumption caused by energizing a large-capacity load capacitor and to stop power supply to the load.

<Effect of Claim 4> In the power saving mode, processing such as analysis and display performed in the normal mode is not necessary, so by omitting these items, power consumption can be reduced.

<Effect of Claim 5> In the power saving mode,
Since a small amount of current can be supplied to the humidity sensor, by keeping the humidity sensor at the idling temperature, the operation of the sensor can be stabilized early when returning to the normal operation mode.

<Effect of Claim 6> The user can manually set the mode while viewing the menu selection screen.

<Effect of Claim 7> When the first switch is turned on, the electric device receives the signal and the second switch is turned on. Since the second switch is controlled by the control means, power consumption can be reduced by turning off the second switch when the electronic device is in the standby state.

<Effect of claim 8> Since the three-terminal switch is adopted, not only the switch for turning on / off the power supply but also the on / off state of the contact can be seen by the control means after the power is turned on. Therefore, it can also be used as an input key for cancel, stop, and the like.

<Effect of Claim 9> Since the latching relay remains closed even if the processing is cut off in the middle, such as when the power plug is unplugged during operation, the power plug is plugged into the power outlet. When the power is turned on again, the power is supplied to the control means and the like, so that the operation can be immediately restored.

<Effect of Claim 10> The value of the power supply voltage to be supplied is fetched into the control means by utilizing resistance voltage division or the like, and for example, when a voltage of AC 200V is supplied to an electric device operating at AC 100V. As described above, when there is an input outside the operating range, the second switch is turned off to stop the power supply and ensure safety.

[Brief description of drawings]

FIG. 1 is a circuit diagram of an electric device according to a first embodiment of the present invention.

FIG. 2 is a flowchart of processing of the electric device.

FIG. 3 is an exemplary waveform diagram for explaining the difference in operation of the CPU between the normal operation mode and the power saving mode in the electric device.

FIG. 4 is a diagram showing an example of an initial setting screen of a screen display unit of the electric device.

FIG. 5 is a diagram showing an example of a menu screen of the screen display unit.

FIG. 6 is a circuit diagram of an electric device according to a second embodiment of the present invention.

FIG. 7 is a flowchart of processing of the electric device.

FIG. 8 is a circuit diagram of an electric device according to a third embodiment of the present invention.

FIG. 9 is a circuit diagram of an electric device according to a fourth embodiment of the present invention.

FIG. 10 is a characteristic diagram of a latching relay of the electric device.

[Explanation of symbols]

1 power plug 2 outlet plugging judgment circuit 3 power transformer 4 Full wave rectifier circuit 5 Power saving operation control circuit 6 CPU operating power supply circuit 7 AH sensor minute current circuit 8 Power supply synchronization signal generation circuit 9 CPU 10 Operation panel 11 Mode switching key RA AH sensor LD photodiode PT1 photo coupler

Claims (10)

[Claims] 1. An electric device comprising a load, control means for driving and controlling the load, and a power supply circuit for supplying electric power to the load and the control means, wherein the control means supplies rated power to the load. An electric device having a normal operation mode for supplying and a power saving mode for limiting power supply to the load, wherein the normal operation mode or the power saving mode is set according to a predetermined condition. 2. The electric device according to claim 1, wherein the electric device is a heating cooker, and the normal operation mode is set when the predetermined condition is when a cooking menu selection screen is displayed. 3. The power supply circuit, a rectifying circuit for rectifying an AC power supply, a load smoothing capacitor for smoothing an output of the rectifying circuit to supply power to the load, the load and the load in the power saving mode. 2. The electric device according to claim 1, further comprising switch means for limiting power supply to the load smoothing capacitor. 4. The electric device according to claim 1, wherein the control means has a plurality of processing items, and the number of processing items to be executed is reduced in the power saving mode. 5. The electric device is a heating cooker, and a circuit is provided for supplying a current to a humidity sensor using a self-heating type heating element whose electric power supply is limited by the switch means. The electric device according to 3. 6. The electric device according to claim 1, wherein a display for manually setting the power saving mode is provided on a menu selection screen, and the control means sets the power saving mode by selecting the display. 7. An electric device comprising a load, control means for driving and controlling the load, and a power supply circuit for supplying electric power to the control means, the first switch controlling electric power supply to the control means. And a second switch connected in parallel with the first switch, wherein the control means controls the second switch which is turned on by receiving electric power from the first switch. machine. 8. A single throw, two pole, three pole switch as the first switch.
A terminal switch is employed, one of the two poles is connected to a power supply circuit and the other is connected to an input circuit to the control means, and the first switch is controlled after the second switch is turned on. The electric device according to claim 7, wherein the electric device is an input device to the device. 9. The electric device according to claim 7, wherein a latching relay that holds an on / off state is adopted as the second switch. 10. A detection means for detecting a power supply voltage supplied to the power supply circuit is provided, and the control means turns off the second switch when the detected power supply voltage is out of a predetermined voltage range. The electric device according to claim 7.