JPH05122990A - Controller for electric apparatus - Google Patents

Abstract

PURPOSE:To reduce a manufacturing cost of a switch and to effectively turn OFF a DC power source even if a control circuit is run away by providing a switch for turning OFF the power source in a current path for connecting a driving circuit to the power source., and providing a switch for turning OFF the power source in a current path of an exciting coil to which the DC power source voltage is supplied. CONSTITUTION:When a switch (SW) 22 for turning ON a power source is closed, a DC voltage is supplied to an amplifier 19 through a current path 21, a current path 26, i.e., an exciting coil 24 is energized, and the SW 22 is held in an ON state. That is, a solenoid valve 6 and a cleaning motor 8 are controlled to be energized or interrupted. Then, when an SW 25 for turning OFF the power source is closed, the coil 24 is energized, and hence the SW 22 is opened. That is, since the DC voltage from a DC power source circuit 14 is not applied to an amplifier 19, a microcomputer 14 cannot control to conduct triacs 7, 9, 10 through the amplifier 19.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control device for an electric device having an improved switch structure for turning on / off the power of the electric device.

[0002]

2. Description of the Related Art In an electric machine, for example, a washing machine, a power switch is provided on an upper surface of a main body, and the power is turned on / off by operating the power switch.
The power switch is a switch for both powering on and powering off, and has a latch mechanism that turns on the power when pushed and mechanically latches at the pushed position, and keeps the on state. It is like this. Then, when the power switch is further pushed in the ON state, that is, in the push position, the mechanical latch mechanism is released and returns to the original projecting position to turn off the power. The power switch is provided in the power line connecting the AC power source and the load.

Further, the washing machine is provided with a so-called automatic power-off function. This function is a function of automatically turning off the power when, for example, 10 minutes have passed after the washing operation is completed. Specifically, a solenoid is provided to release the mechanical latching mechanism of the power switch,
The solenoid is configured to be controlled by a control circuit, such as a microcomputer, for switching on and off.

[0004]

However, in the above-mentioned conventional structure, since the power switch must be provided in the power line, a power switch having excellent withstand voltage and current resistance must be used. There is a drawback that the manufacturing cost of the switch is high. Further, the power switch must be provided with a mechanical latch mechanism and a solenoid for releasing this latch mechanism, which complicates the configuration of the switch.
Since it is necessary to use a relay of 00V, there is a problem that the manufacturing cost is also high.

On the other hand, in order to reduce the manufacturing cost, a relay switch having no mechanical latch mechanism is provided in the power supply line, and an operation switch composed of a push switch is provided as the power supply switch. A configuration is conceivable in which a switch signal is given to the control circuit, and the control circuit turns on and off the relay coil by controlling the disconnection of the relay coil according to the operation of the operation switch.

In the case of this configuration, the operation switch as the power switch can be formed of a push switch, and
This operation switch has a control signal level voltage of, for example, 12
Since only a voltage of about V is applied, the manufacturing cost of the operation switch is low. Also, since the relay does not need a mechanical latch mechanism, its manufacturing cost is low. For this reason,
The manufacturing cost of the power switch can be reduced. Further, since the relay circuit is driven and controlled by the control circuit to turn off the relay switch, it is possible to automatically turn off the power after the operation is completed.

However, in the above configuration, if the control circuit goes out of control for some reason, even if the user turns off the operation switch, the control circuit goes out of control, so the relay switch can be turned off. There is a risk that the power cannot be turned off. That is, the above configuration could not be commercialized in practice.

Therefore, an object of the present invention is to provide a control device for electric equipment which can reduce the manufacturing cost of the power switch and can surely turn off the power supply even when the control circuit runs out of control. is there.

[0009]

SUMMARY OF THE INVENTION A control device for electric equipment according to the present invention comprises a drive circuit for controlling interruption and disconnection between an AC power supply and a load, a control circuit for controlling this drive circuit, the drive circuit and A control device for an electric device, comprising a DC power supply for applying a DC voltage to the control circuit, comprising a power-on operation switch provided in an energizing path connecting the drive circuit and the DC power supply. Along with, an exciting coil is provided for holding the operation switch in an ON state when the energization path is controlled by the control circuit and energized to the energization path provided with the operation switch. The present invention is characterized in that it is provided with an operation switch for turning off the power to turn off the operation coil by turning off the exciting coil.

[0010]

According to the above means, since the operation switch for turning on the power supply is provided in the energizing path connecting the drive circuit and the DC power supply, the operation switch for turning on the power supply has not much withstand voltage and current resistance. Not required. Further, since the operating switch for turning off the power is provided in the energizing path of the exciting coil to which the DC power is supplied, the operating switch for turning off the power is not required to have much withstand voltage and current. Therefore, the manufacturing cost of the power-on operation switch and the power-off operation switch can be reduced.

Further, since the exciting coil holds the operating switch for turning on the power source, and the operating switch is not required to have withstand voltage and current resistance so much, the exciting coil and the power source are turned on. The operation switch for the can be composed of an ordinary DC relay. Therefore, the structure can be simplified and the cost can be reduced as compared with the conventional structure in which a mechanical latch mechanism is provided and a solenoid for releasing the latch mechanism must be provided.

When the user does not operate the operation switch for turning off the power, after the operation is completed, for example, 10
When the exciting coil is turned off by the control circuit when the minutes have passed, the operation switch for turning on the power is turned off and the power is automatically turned off.

Further, even if the control circuit runs out of control, if the operation switch for turning off the power is operated, the exciting coil is cut off and the operation switch for turning on the power is turned off, so that the power can be surely turned off. ..

[0014]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A first embodiment in which the present invention is applied to a washing machine will be described below with reference to FIG. In FIG. 1, power source buses 2 and 3 are led out from a power source plug 1 connected to a commercial AC power source (not shown). A primary winding 5a of a transformer 5 of a DC power supply circuit 4, which is a DC power supply, is connected between the power supply buses 2 and 3.

A load, for example, a solenoid valve 6 and a triac 7 are connected in series between the power source buses 2 and 3, and a load, for example, washing motors 8 and 2 are connected.
A circuit consisting of individual triacs 9 and 10 is connected. In this case, the forward rotation side terminal 8a of the washing motor 8 is connected to the triac 9 and the reversal side terminal 8b is
Are connected to the triac 10. The solenoid valve 6
Is a water supply valve for supplying water into, for example, a washing tub (not shown). The washing motor 8 is a motor that drives an agitator (not shown) in the washing tub in the forward and reverse directions.

On the other hand, in the DC power supply circuit 4, the secondary winding 5b of the transformer 5 is connected to the input terminal of the rectifier circuit 11. A smoothing capacitor 12 is connected to the output terminal of the rectifier circuit 11, and the rectified output from the rectifier circuit 11 is smoothed by this capacitor 12. The DC voltage output from both terminals of the capacitor 12, that is, the output terminal of the DC power supply circuit 4, is applied to the control circuit, for example, the microcomputer 14 via the constant voltage circuit 13.

The constant voltage circuit 13 includes a transistor 1
5, a Zener diode 16, a resistor 17 and a capacitor 18, and is configured to receive a DC voltage output from the DC power supply circuit 4 and apply a predetermined constant voltage to the microcomputer 14.

Further, the microcomputer 14 is configured to give a drive signal to the gates of the triacs 7, 9 and 10 via a drive buffer, for example, an amplifier circuit 19. As a result, the microcomputer 1
4 is a triac 7, 9, 10 via the amplifier circuit 19.
The electromagnetic valve 6 and the washing motor 8 are controlled to be turned on and off by driving and controlling each of them.

Specifically, when the triac 7 is conduction-controlled, the solenoid valve 6 is energized, and when the triac 9 is conduction-controlled, the washing motor 8 is energized in the forward direction.
When the triac 10 is conduction-controlled, the washing motor 8 is energized and driven in the reverse direction. In this case, the drive circuit 20 is composed of the amplifier circuit 19 and the triacs 7, 9, 10.

Now, in the energizing path 21 connecting the voltage application terminal 19a of the amplifier circuit 19 and the positive output terminal of the DC power supply circuit 4, an operation switch 22 for turning on the power supply is provided.
Is provided. This operation switch 22 is, for example, D
It is composed of a relay switch of the C relay 23 and is a normally open type switch. Excitation coil 24 of the relay 23
Has one end connected to a terminal of the operation switch 22 on the side of the amplification circuit 19, and the other end connected to the microcomputer 14 via the operation switch 25 for powering off and the amplification circuit 19. The operation switch 25 for turning off the power source is, for example, a push switch and is a normally closed switch.

As a result, the exciting coil 24 is constructed so that it is controlled to be turned on and off by the microcomputer 14 via the amplifier circuit 19, and at the same time the operation switch 2 is operated.
When the switch 2 is turned on and the energizing path 26, that is, the exciting coil 24 is energized, the operation switch 22 is held in the on state. The energization paths 21 and 26 are set so that a DC voltage of, for example, + 12V is applied, and thus the operation switches 22 and 25 are also +.
A DC voltage of 12V is applied.

Further, the operation switch 25 of the exciting coil 24
The terminal on the side is connected to the input terminal of the microcomputer 14, and the microcomputer 14 detects the terminal voltage on the side of the operation switch 25 of the exciting coil 24 so that the operation switch 22 for turning on the power is turned on. It is configured to detect whether or not there is. In this case, when the operation switch 22 is off, the terminal voltage on the operation switch 25 side of the exciting coil 24 becomes high level, and when the operation switch 22 is on, the terminal voltage on the operation switch 25 side of the exciting coil 24. Becomes low level.

The power-on operation switch 22 and the power-off operation switch 25 are provided on an operation panel (not shown). Further, the operation panel is provided with various switches and indicators for setting a washing operation course and the like.

Next, the operation of the above configuration will be described. When the power plug 1 is connected to a commercial AC power source, a DC voltage is applied from the DC power supply circuit 4 to the microcomputer 14 via the constant voltage circuit 13. In this state, the microcomputer 14 outputs a drive signal for energizing the exciting coil 24 to the amplifier circuit 19.

In the above state, when the user pushes the operation switch 22 for turning on the power to turn it on, a DC voltage is applied to the amplifier circuit 19 through the energizing path 21, and the energizing path 26, that is, the excitation. When the coil 24 is energized, the operation switch 22 is held in the ON state. As a result, even when the pushing operation of the operation switch 22 is stopped, the operation switch 22 remains in the ON state.

In this state, a DC voltage of, for example, +12 V from the DC power supply circuit 14 is passed through the energizing path 21 and the amplifier circuit 1
9 is applied to the microcomputer 14
Can drive and control the triacs 7, 9 and 10 via the amplifier circuit 19, that is, can control the solenoid valve 6 and the washing motor 8 to be turned on and off. In this case, the microcomputer 14 controls the solenoid valve 6 based on the set washing operation course and the control program stored in advance.
Also, the washing motor 8 is turned on and off.

Now, when turning off the power, when the user pushes the operation switch 25 for turning off the power,
Since the exciting coil 24 is cut off, the operation switch 22 is turned off. As a result, the DC voltage is not applied to the amplifier circuit 19 from the DC power supply circuit 14, so that the microcomputer 14 cannot control the conduction of the triacs 7, 9, 10 via the amplifier circuit 19. That is, the solenoid valve 6 and the washing motor 8 are held in a disconnected state,
The power supply to the loads such as the solenoid valve 6 and the washing motor 8 is turned off.

After the washing operation is completed, for example, 10
After a lapse of minutes, the microcomputer 14 automatically turns off the power. Specifically, 10 after the end of operation
When the minutes have passed, the drive signal for energizing and driving the exciting coil 24 from the microcomputer 14 is not output to the amplifier circuit 19, and the exciting coil 24 is cut off. By turning off the exciting coil 24, the operation switch 22 is turned off, so that the DC voltage is not applied from the DC power supply circuit 14 to the amplifier circuit 19, and the power is automatically turned off.

On the other hand, if the microcomputer 14 runs out of control due to some accident, the washing operation may not end, and the electromagnetic valve 6 and the washing motor 8 may continue to be energized. When the user notices such an accident, the user can surely turn off the power by pushing the operation switch 25 for turning off the power to turn off the exciting coil 24.

Further, according to the above embodiment, the drive circuit 20
Since the operation switch 22 for turning on the power is provided in the energization path 21 that connects between the power supply circuit 4 and the DC power supply circuit 4, the operation switch 22 for turning on the power is not required to have high withstand voltage and current resistance. Further, since the operation switch 25 for turning off the power is provided in the energization path 26 of the exciting coil 24 to which the DC power is supplied, the operation switch 25 for turning off the power supply is not required to have much withstand voltage and current resistance. Therefore, the manufacturing cost of the power-on operation switch 22 and the power-off operation switch 25 can be reduced.

Further, since the exciting coil 24 and the power-on operation switch 22 can be constituted by an ordinary DC relay 23, a mechanical latch mechanism is provided and a solenoid for releasing this latch mechanism is provided. The switch configuration can be simplified and the manufacturing cost can be reduced as compared with the conventional configuration that must be provided.

FIG. 2 is an electric circuit diagram showing a second embodiment in which the present invention is applied to a dryer. In FIG. 2, from the power plug 31 connected to the commercial AC power source to the power bus 3
2 and 33 have been derived. A primary winding 35a of a transformer 35 of a DC power supply circuit 34, which is a DC power supply, is connected between the power supply buses 32 and 33. Also,
A load, for example, a heater 36 and a relay switch 38 of a relay 37 are connected in series between the power source buses 32 and 33.

In the DC power supply circuit 34, the first secondary winding 35b of the transformer 35 is the first rectifier circuit 39.
Is connected to the input terminal of. A smoothing capacitor 40 is connected to the output terminal of the first rectifier circuit 39, and the rectified output from the rectifier circuit 39 is smoothed by this capacitor 40. On the other hand, the second secondary winding 35c of the transformer 35 is connected to the input terminal of the second rectifier circuit 41. A smoothing capacitor 42 is connected to the output terminal of the second rectifier circuit 41, and the rectified output from the rectifier circuit 41 is smoothed by this capacitor 42.

The DC voltage output from both terminals of the capacitor 40, that is, the first output terminal of the DC power supply circuit 34, is
The voltage is applied via a constant voltage circuit 43 to a control circuit, for example, a microcomputer 44. The constant voltage circuit 43 includes a transistor 45, a Zener diode 46, a resistor 47 and a capacitor 48, and receives a DC voltage output from the DC power supply circuit 34 and applies a predetermined constant voltage to the microcomputer 44. Is configured.

Further, between one terminal of the capacitor 42, that is, the positive side terminal of the second output terminals of the DC power supply circuit 34, and the terminal 44a of the microcomputer 44,
The operation switch 49 for turning on the power source, the exciting coil 50 of the relay 37, and the knot gate 51 are connected in series. Accordingly, the microcomputer 44 is configured to control the drive of the exciting coil 50 via the knot gate 51, thereby turning on / off the relay switch 38 and controlling the on / off of the heater 36.

In this case, the relay switch 38 and the exciting coil 50, that is, the relay 37 constitute a drive circuit. The operation switch 49 is constituted by a relay switch of the DC relay 52, for example, and is a normally open type switch. The operation switch 49 is provided in the energizing path 53 that connects the exciting coil 50 of the relay 37, that is, the drive circuit, and the DC power supply circuit 34.

On the other hand, the exciting coil 5 of the DC relay 52
4 has one end connected to the terminal of the operation switch 49 on the side of the exciting coil 50, and the other end connected to the terminal 44b of the microcomputer 44 via the operation switch 55 for turning off the power and the knot gate 56. The power-off operation switch 55 is, for example, a push switch and is a normally closed switch.

As a result, the exciting coil 54 is constructed so that the microcomputer 44 controls the switching on and off through the knot gate 56, and the operation switch 49 is turned on to turn on the energizing path 57, that is, the exciting coil. When the switch 54 is energized, the operation switch 49 is held in the ON state.

The terminal of the exciting coil 54 on the operation switch 55 side is connected to the terminal 44c of the microcomputer 44, and the microcomputer 44 detects the terminal voltage of the exciting coil 54 on the operation switch 55 side. It is configured to detect whether or not the operation switch 49 for powering on is turned on. In this case, when the operation switch 49 is off, the terminal voltage on the operation switch 55 side of the exciting coil 54 becomes high level, and when the operation switch 49 is on, the terminal voltage on the operation switch 55 side of the exciting coil 54. Becomes low level.

The operation switch 49 for turning on the power source is also provided.
The power-off operation switch 55 is provided on an operation panel (not shown). The operation panel is provided with various switches and indicators for setting a dry operation course and the like.

Next, the operation of the above configuration will be described. When the power plug 31 is connected to a commercial AC power source, a DC voltage is applied from the DC power supply circuit 34 to the microcomputer 44 via the constant voltage circuit 43. In this state, the microcomputer 44 outputs a drive signal for energizing and driving the exciting coil 54.

In the above state, when the user pushes the operation switch 49 for turning on the power to turn it on, the energizing path 53
A direct current voltage is applied to the exciting coil 50 of the relay 37 via the switch 37 and the energizing path 57, that is, the exciting coil 54 is energized, whereby the operation switch 49 is held in the ON state. As a result, even when the pushing operation of the operation switch 49 is stopped, the operation switch 49 remains in the ON state.

In this state, a DC voltage from the DC power supply circuit 34 is passed through the energizing path 53 to the exciting coil 50 of the relay 37.
Is applied to the microcomputer 44,
The heater 36 can be turned on and off by turning on and off the relay switch 38 by turning on and off the exciting coil 50 of the relay 37. In this case, the microcomputer 44 performs the on / off control of the heater 36 based on the set dry operation course and the control program stored in advance.

When turning off the power, when the user pushes the operation switch 55 for turning off the power,
Since the exciting coil 54 is cut off, the operation switch 49 is turned off. As a result, the DC voltage is not applied from the DC power supply circuit 34 to the exciting coil 50 of the relay 37, so that the relay switch 38 is turned off and the microcomputer 44 controls the relay switch 38 to be turned on / off via the exciting coil 50. Can't do it. That is, the heater 36 is held in the disconnected state, and the heater 3
The power is turned off for loads such as 6.

After completion of the drying operation, for example, 10
After a lapse of minutes, the microcomputer 44 automatically turns off the power. Specifically, 10 after the end of operation
When the minutes have elapsed, the microcomputer 44 does not output a drive signal for energizing and driving the exciting coil 54, so that the exciting coil 54 is cut off. By turning off the exciting coil 54, the operation switch 49 is turned off, so that the DC voltage from the DC power supply circuit 34 is not applied to the exciting coil 50 of the relay 37, and the power is automatically turned off.

On the other hand, if the microcomputer 44 runs out of control due to some accident, the drying operation may not end and the heater 36 may continue to be energized. When the user notices such an accident, the user can surely turn off the power by pushing the operation switch 55 for turning off the power to turn off the exciting coil 54.

Therefore, also in the second embodiment, it is possible to obtain substantially the same effect as in the first embodiment.

In the above embodiment, neither the drum for accommodating clothes, the fan for supplying warm air into the drum, nor the motor for rotating the drum and the fan are shown, but the above is not shown. The motor is configured to be controlled to be turned on and off by a microcomputer 44 via a drive circuit (not shown) including a relay and the like. Then, for the drive circuit of this motor, the operation switch 4 for turning on the power source is operated in substantially the same manner as the relay 37.
A direct current voltage is applied via 9.

Further, although the present invention is applied to the washing machine and the dryer in each of the above-mentioned embodiments, the present invention is not limited to these and can be applied to, for example, an automatic dishwasher.

[0050]

As is apparent from the above description, the present invention is provided with an operation switch for turning on the power provided in the energizing path connecting the drive circuit and the DC power source, and is cut off by the control circuit. An energizing coil is provided that keeps the operating switch in the ON state when the energizing path is electrically controlled and the energizing path is energized.The energizing coil installed in the energizing path of this exciting coil turns off the operating switch Since it has a configuration with an operation switch for turning off the power to operate,
This has an excellent effect that the manufacturing cost of the power switch can be reduced and the power can be surely turned off even when the control circuit runs out of control.

[Brief description of drawings]

FIG. 1 is an electric circuit diagram showing a first embodiment of the present invention.

FIG. 2 is an electric circuit diagram showing a second embodiment of the present invention.

[Explanation of symbols]

4 is a DC power supply circuit (DC power supply), 6 is a solenoid valve (load),
7 is a triac, 8 is a washing motor (load), 9 and 10
Is a triac, 14 is a microcomputer (control circuit), 19 is an amplifier circuit, 20 is a drive circuit, 21 is an energizing path, 22 is a power-on operation switch, 23 is a DC relay, 24 is an exciting coil, and 25 is power off. Operation switch, 26 is an energizing path, 34 is a DC power supply circuit (DC power supply),
36 is a heater (load), 37 is a relay (drive circuit), 3
Reference numeral 8 is a relay switch, 44 is a microcomputer (control circuit), 49 is a power-on operation switch, 50 is an exciting coil, 52 is a DC relay, 53 is an energizing path, 54 is an exciting coil, and 55 is an operation for turning off the power. A switch, 57 indicates an energization path.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display location H01H 51/04 7826-5G

Claims (1)

[Claims] 1. A drive circuit for controlling interruption and disconnection between an AC power supply and a load, a control circuit for controlling the drive circuit, and a DC power supply for applying a DC voltage to the drive circuit and the control circuit. In a control device for electric equipment, the operating switch for turning on the power supply provided in the energizing path connecting the drive circuit and the DC power supply, and the operating switch controlled to connect and disconnect by the control circuit are provided. An exciting coil for holding the operation switch in an ON state when the energized path is energized, and a power-off for turning off the operation switch by disconnecting the exciting coil provided in the energizing path of the exciting coil And a control switch for an electric device.