KR960000356B1 - Disconnection circuit of washing machine - Google Patents

Abstract

The circuit includes a right and left reversing circuit for reversing a washing motor with a snubber having first and second transistors connected to a microcomputer, triacs connected to the first and second transistors, resistances, and a condenser; a third transistor connected to the microcomputer; and a triac connected to the third transistor. The circuit further includes a fourth transistor having terminal connected to the microcomputer and the other terminal connected to the third transistor.

Description

Power cut-off circuit of washing machine drive motor

1 is a circuit diagram configured to reverse the left and right sides of a conventional washing machine driving motor.

FIG. 2 is a left and right inverted circuit diagram in which the power cut-off circuit of the present invention is configured, and shows an integrated circuit and a transistor added to the circuit of FIG.

3 shows waveforms of voltages input to respective transistors in a control microcomputer.

* Explanation of symbols for main parts of the drawings

Q1, Q2, Q3, Q4: Transistors R1, R2: Resistance

C1, C2: Condenser T1, T2, T3: Triac

M: Drive Motor SW: Switch

IC1: integrated circuit IC2: control microcomputer

[Field of Invention]

The present invention relates to a left and right inverting circuit of a washing machine. More specifically, the present invention relates to a power cut-off circuit of a washing machine driving motor for forcibly shutting down when elements of the left and right inverting circuits are destroyed and a reverse voltage is simultaneously applied to the driving motor of the washing machine.

[Background of invention]

In the conventional washing machine, the object was achieved by controlling the driving motor by using a left and right inversion circuit controlled by a microcomputer in order to make the pulsator installed inside the washing tank left and right inverted for a predetermined time.

However, when a momentary overcurrent flows through the triac, which is an element that controls the left and right rotation of the driving motor, the voltage is applied to the driving motor in different directions at the same time. Therefore, when this condition persists, a problem occurs in that the coil of the driving motor is destroyed.

That is, when the bidirectional voltage is applied to the drive motor, the rotation is stopped, and the voltage is continuously supplied, thereby generating a noise such as a hum and overheating, and finally the coil is disconnected.

However, housewives, who are usually the majority of users, can't handle this effectively and the driving motors are often damaged.

In order to solve this problem, a device which blocks the operation of the load by using a hall sensor or a sensor of a load sensing unit has been conventionally used, but this is a complicated circuit and a separate sensor is used or combined. A malfunction occurred.

The present inventors have made the present invention which can solve the above problem simply by adding an integrated circuit element and a transistor to the conventional circuit.

[Summary of invention]

According to the present invention, an integrated circuit having a terminal for inputting a signal from a left inversion control terminal of a control microcomputer and a terminal for inputting a signal from a right inversion control terminal in a circuit for inverting left and right in a conventional washing machine driving motor. It is characterized by consisting of a transistor connected to the output terminal of the circuit element and coupled to another transistor.

[Description of Specific Example of the Invention]

The present invention relates to a power cut-off circuit for preventing the driving motor (M) from being damaged by applying a bidirectional voltage to the driving motor (M) of the washing machine. The circuit of the present invention includes an integrated circuit device and a transistor in a conventional circuit. In addition, it can be configured simply.

In particular, the integrated circuit device is connected to an input terminal such that a signal is input from the left and right inverting terminals of the microcomputer controlling the washing machine driving motor M, and the output terminal of the integrated circuit device is connected to a transistor.

This transistor is connected to another transistor, which is operated by a signal of a control microcomputer and belongs to a conventional circuit installed to drive a triac.

The triac is also a conventional one and automatically cuts off the power by shorting the power switch when washing is terminated.

The power switch is also used in the related art, and a solenoid coil is included therein. When the triac operates and current flows, the solenoid coil operates to release the terminal of the internally locked switch to cut off the power supply.

1 is a conventional left and right inversion control circuit diagram used in a washing machine, and includes a first transistor and a second transistor Q1, respectively connected to the left and right terminals for the control microcomputer IC2. Q2), the triacs T1 and T2 connected to the first and second transistors Q1 and Q2, respectively, and the resistors R1 and R2 and the capacitors C1, respectively connected in parallel with the triacs T1 and T2, respectively. It consists of the snubber circuit comprised by C2).

When not in use (i.e., not in the washing stroke), the low signals L and L are output to the terminals a and b, respectively. ) Signal is output.

When the washing process starts, the high signal from the left-hand terminal (a) of the washing machine control microcomputer IC2 is input to the first transistor Q1. When a voltage is applied to the first transistor Q1, the first triac T1 is operated, and accordingly, the driving motor M starts to rotate.

At this time, since the signal is not output to the right side dedicated terminal b of the microcomputer, the second transistor Q2 does not operate. The duration of the signal output from the terminals a, b of the microcomputer IC2 is a cycle of inversion of the washing machine. The period of the signal is shown in FIG. The times t1 and t2 output from the terminals a and b are times programmed in advance by the washing machine control microcomputer IC2, and the periods of the times t1 and t2 may or may not be the same.

When the signal output from the terminal a of the control micom to the first transistor Q1 is stopped and a high signal is output from the terminal b of the control micom, a voltage is applied to the second transistor Q2. The voltage applied to the second transistor Q2 operates the second triac T2.

When the second triac T2 is operated, a voltage is supplied to the driving motor M. The voltage is first driven in the direction of the driving motor M by a signal output from the left-only terminal a of the control microcomputer IC2. And rotate in the opposite direction.

Since the voltages output from the terminals a and b of the control microcomputer IC2 are alternately applied to each of the transistors Q1 and Q2 as shown in FIG. 3, the driving motor M is Periodically turn left and right turns to continue washing.

Composed of resistors R1 and R2 and capacitors C1 and C2 connected in parallel with each of the first and second triacs T1 and T2, a snubber used to protect the triac from overcurrent Circuit.

Terminal (c) of the control microcomputer (IC2) is a terminal for automatically outputting a signal to automatically cut off the main power supply of the washing machine after a certain time elapses after the washing administration. The signal output from the terminal c drives the third transistor Q3.

When the third transistor Q3 is operated, a voltage is supplied to the third triac T3 to operate the third triac T3, thereby operating the switch SW to cut off the main power.

The switch SW has a solenoid coil installed therein, and when the third triac T3 operates, a current is supplied to the solenoid coil to short-circuit the switch SW.

According to the present invention, an integrated circuit IC1 having an input terminal connected to the left and right half dedicated terminals a and b of the control microcomputer IC2 and a fourth transistor Q4 connected to an output terminal of the integrated circuit IC1 are respectively provided. It is added to the conventional circuit.

The integrated circuit IC1 also outputs a high (H) signal when the output signals of the terminals (a) and (b) are the high (H) signals, respectively. AND GATE).

The output of the integrated circuit IC1 is connected to the base terminal of the fourth transistor Q4. The fourth transistor Q4 is again connected to the base terminal of the third transistor Q3.

The base terminal of the third transistor Q3 is connected to the terminal c of the control microcomputer IC2. The operation type serves to cut off the main power when the washing operation is terminated as described above.

The operation and effects of the present invention configured as described above are as follows.

When either of the first triac or the second triac T1 and T2 is broken, the first triac and the second triac T1 and T2 alternately output a high signal and a low signal. Even though the drive motor (M) to rotate in turn alternately due to a malfunction of the triac itself outputs a high signal or a low signal. When the first triac and the second triac T1 and T2 simultaneously output a low signal, the driving motor M itself is broken or noisy because no driving voltage is applied in any direction of the driving motor M. On the contrary, when the first triac and the second triac T1 and T2 simultaneously output a high signal, although the driving voltage is applied to the driving motor M in both directions, the rotation may be performed. Excessive self-load is applied to the drive motor (M), and excessive generation of joule heat in the drive motor (M) eventually causes the drive motor (M) to cause serious damage or breakage, and also a considerable noise during non-breakage. Will be generated. Accordingly, when the first triac and the second triac T1 and T2 simultaneously output a high signal, the integrated circuit IC1 connected to these terminals, that is, the AND gate, outputs a high signal, thereby providing a high signal. In addition, the fourth transistor Q4 connected to the output terminal of the integrated circuit IC1 is connected.

When the fourth transistor Q4 operates, the third transistor Q3 operates accordingly, and the third triac T3 is driven to short-circuit the switch SW.

In addition, since the terminal c of the control microcomputer IC2 is connected to the base terminal of the third transistor Q3, the main power is cut off when the washing process is normally completed by a program built in the control microcomputer IC2. Output the signal to cut off the main power supply and end the washing process.

As described above, the power cut-off circuit of the washing machine driving motor M of the present invention is to prevent damage of the driving motor M caused by the breakage of the triac in a circuit for turning the driving motor M to the left and right. A separate integrated circuit and a transistor are added to protect the driving motor (M).

In particular, according to the present invention, it is easy to assemble the washing machine and it is possible to reliably prevent the damage of the driving motor M due to the breakage of the triac.

Although the invention has been described in terms of the described embodiments, modifications and variations are apparent to those skilled in the art to which the invention pertains without departing from the spirit and scope of the invention and should be limited by the appended claims.

Claims (4)

Triacs T1 and T2 connected to the first and second transistors Q1 and Q2 connected to the terminals a and b of the control microcomputer IC2, respectively, and to the first and second transistors Q1 and Q2. ) And the left and right sides of the washing machine for turning the washing machine driving motor M including the snubber circuit composed of the resistors R1 and R2 and the capacitors C1 and C2 connected in parallel with the triacs T1 and T2, respectively. Right reverse circuit; In the third transistor Q3 connected to the terminal c of the control microcomputer IC2 and the triac T3 connected to the third transistor Q3, respectively, at terminals a and b of the microcomputer IC2. An integrated circuit IC1 having an input terminal connected thereto and a fourth transistor Q4 having one end connected to an output terminal of the integrated circuit IC1 and the other end connected to a third transistor Q3. Power cutoff circuit of motor (M). The power cut-off circuit of the driving motor (M) of the washing machine according to claim 1, wherein the integrated circuit (IC1) is an AND gate. The power cut-off circuit of a driving motor (M) of a washing machine according to claim 1, wherein the fourth transistor (Q4) is connected to the base terminal of the third transistor (Q3). The power cut-off circuit of the washing machine driving motor (M) according to claim 2, wherein all of the signals input to the input terminal of the AND gate are high signals.