JPH04343888A - Washing machine reversing apparatus - Google Patents

Abstract

PURPOSE:To prevent a washing motor from the exertion of a reverse force even if a reverse signal is outputted in running a washing machine by an erroneous operation of a microcomputer while the left and right rotation for washing are changed over to each other. CONSTITUTION:Transistors 21, 22 for driving TRIACs 7, 9 are provided between the output signals 27, 28 of a microcomputer and the triacs 7, 9 for supplying current to motor coils 11, 12 for left and right rotation according to the output signals 27, 28. There are provided a diode 26 for connecting a collector of the transistor 21 to a base signal circuit of the other transistor 22 and a diode 25 for connecting a collector of the other transistor 22 to a base signal circuit of one transistor 21.

Description

[Detailed description of the invention]

0001

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a washing machine having a reversing device for switching the rotation of a washing motor from left to right using a microcomputer in a washing operation mode.

0002

[Prior Art] A washing machine is equipped with a control device such as a microcomputer, in which the washing rotation direction, the number of washing and spin-drying cycles, the operating time, etc. are set, and the washing operation is performed according to this operating mode. There is something I did.

[0003] Next, the circuit for switching left and right rotation in such an operation mode will be explained with reference to FIG. 4 and the like to the microcomputer 5.

Reference numeral 6 denotes a triac drive unit for rotation, which is operated by an output signal from the microcomputer 5 to turn on the triac 7 for left rotation.

Reference numeral 8 denotes a triac drive unit for clockwise rotation, which is operated by an output signal from the microcomputer 5 to turn on the triac 9 for clockwise rotation.

10 is a motor for washing, 11 is a coil for counterclockwise rotation, and 12 is a coil for clockwise rotation. 13 is a phase advance capacitor that drives the motor 10.

[0007] In order to perform a washing operation with the above configuration, the desired operation mode is set using a select switch (not shown), etc., and then the power switch 14 is turned on. Power is supplied to the transformer 1, and its secondary The voltage is stepped down, rectified by a rectifier diode 3, smoothed by a smoothing capacitor 4, and supplied to a microcomputer 5, thereby starting washing as programmed in the microcomputer 5 in advance.

That is, the left rotation triac drive unit 6 is operated by the output signal of the microcomputer 5, and when the left rotation triac 7 is turned on, the left rotation coil 11 of the motor is energized, and the washing motor 10 rotates to the left. .

After a certain period of time, the rotation of the washing motor 10 is stopped by turning off the output, and then the triac drive unit 8 for right rotation is operated by the output of the microcomputer 5, and the triac 9 for right rotation is turned on. Then, the washing motor 10 is rotated clockwise in the same manner. The washing process is performed by rotating the washing motor 10 in this manner.

0010

[Problem to be Solved by the Invention] During the above-mentioned operation, if the microcomputer 5 malfunctions due to disturbance noise or the like and outputs an output signal for clockwise rotation while rotating counterclockwise, the triac 9 for clockwise rotation will also be turned on, and the washing machine will The left-handed and right-handed motor coils 11 and 12 of the motor 10 are energized at the same time,
Due to the combination of left and right rotational forces, rotation stops and both coils 11
, 12, and the washing motor 1 is heated due to copper loss.
There was a risk of smoke and fire.

[0011]

[Means for Solving the Problem] In order to solve the above problem, between the output port of the microcomputer and each triac that supplies power to the motor coil for left and right rotation,
Transistors for driving these triacs are provided, and diodes are provided between the collector of one transistor and the base of the other transistor, and between the collector of the other transistor and the base of one transistor.

0012

[Operation] Even if the microcomputer outputs a reverse rotation signal while the washing motor is rotating in one direction, no reverse rotation force is applied to the washing motor.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described based on the drawings. FIG. 1 is a circuit diagram of the present invention, in which the same parts as in the conventional example are given the same reference numerals.

The method of supplying the commercial power source 2 to the microcomputer 5 is the same as in the conventional example, so a detailed explanation will be omitted.

Reference numeral 10 denotes a washing motor having a coil 11 for left rotation and a coil 12 for right rotation. 13 is washing motor 1
This is a phase advance capacitor for 0 drive. 7 is a triac for left rotation (hereinafter referred to as L triac), and 9 is a triac for right rotation (hereinafter referred to as R triac). 21 and 22 are transistors that drive the triacs 7 and 9, and are triac drive transistors for left rotation (
A triac drive transistor for clockwise rotation (hereinafter referred to as an R transistor) 21 is connected to the L triac 7 via a resistor A23.
2 is connected to the triac 9 for clockwise rotation via a resistor B24.

25 and 26 are diodes, and diode 2
5 connects the collector of the L transistor 22 and the base of the R transistor 21, and the other diode 26 is
Collector of R transistor 21 and L transistor 2
2 bases are connected. In the above configuration, to perform a washing operation, after setting the desired operation mode using a select switch (not shown), etc., turn the power switch 1 to OFF.
If N is selected, power is supplied to the transformer 1, the voltage is stepped down on the secondary side of the transformer, rectified by the rectifier diode 3, smoothed by the smoothing capacitor 4, and then programmed into the microcomputer 5 in advance by supplying it to the microcomputer 5. Start washing as specified.

When the washing motor 10 is rotated counterclockwise, the output signal 28 for counterclockwise rotation of the microcomputer 5 is set to "H" and the output signal 27 for clockwise rotation is set to "L".

When "H" is output from the signal 28, a voltage divided by three resistors R1, R2, and R3 is applied to the base of the L transistor 21, and the L transistor 21 is turned on.
state, a current flows through the resistor A23 to the gate of the L triac 7, the L triac is turned on, and the washing motor 10 rotates to the left.

At this time, since sufficient voltage is not applied to the base of the R transistor 22, the R transistor 22
is not turned on, and the R triac 9 is turned off.

If the signal 27 also goes high due to a malfunction of the microcomputer 5 due to disturbance noise or the like during the counterclockwise rotation, the L transistor 21 is already turned on, so the collector of the L transistor 21 becomes "H". "L".

As a result, the diode 26 becomes conductive, and a sufficient voltage is not applied to the R transistor 22, so the R transistor 22 does not turn on. That is, no current flows through the clockwise rotation coil 2 of the washing motor 10.

Conversely, when the washing motor 10 is rotating clockwise, the R transistor 21 is turned on. Therefore, due to a malfunction of the microcomputer 5, even if "H" is output from the signal 28, the R transistor 22 is already turned on, so
The collector of the R transistor 22 is at "L".

As a result, the diode 25 becomes conductive, and a sufficient voltage is not applied to the L transistor 21, so the L transistor 21 is not turned on, and no current flows to the counterclockwise rotation coil 11 of the washing motor 10. Not flowing.

After the counterclockwise rotation operation time, the output from the microcomputer 5 is turned off, and the rotation of the washing motor 10 is stopped.
Next, if "H" is output from the signal 27 of the microcomputer 5, the washing motor 10 is rotated clockwise in the same manner. In this way, the washing operation is performed by rotating the washing motor 10 left and right.

When the washing motor 10 is in a stopped state, both the L transistor 21 and the R transistor 22 are in the OFF state, so the collectors of each are in the "H" state. Therefore, the 27 side or 28 of the microcomputer 5 is
”, the diodes 25 and 26 do not become conductive, and a sufficient voltage can be applied to the bases of the L transistor 21 and the R transistor 22.

In the above embodiment, the circuit of a washing machine was used as an example, but the circuit is not limited to this, and can of course be applied to all devices having an electronic control device, as well as other electronic circuits. It can also be applied to equipment.

[0027]

As described above, the reverse rotation prevention device for a washing machine of the present invention prevents the washing motor from rotating in reverse even if the microcomputer malfunctions due to disturbance etc. during operation and outputs a reverse rotation signal. There is no power applied, the washing motor stops, heat generation, and fire.

[Brief explanation of the drawing]

FIG. 1 is a rotation switching control circuit diagram of a washing machine according to the present invention.

FIG. 2 is a rotation switching control circuit diagram of a conventional washing machine.

[Explanation of symbols]

5 Microcomputer 7 Triac for left rotation 9 Triac for right rotation 10 Washing motor 11 Motor coil for left rotation 12 Motor coil for right rotation 21 Triac drive transistor for left rotation 22
Triac drive transistor for clockwise rotation 25 Diode 26 Diode 27 Output signal for counterclockwise rotation 28 Output signal for clockwise rotation

Claims (1)

[Claims] 1. A reversing device that switches the rotational direction of a washing motor from left to right using a microcomputer, including a reversal prevention device that prevents the washing motor from rotating in the opposite direction even if a signal instructing the washing motor to rotate in the other direction is issued while the washing motor is rotating in one direction. A reversing device for a washing machine, characterized in that it is provided with a reversing device.