KR880003030Y1 - Automatic dehydration control circuit for washing machine - Google Patents

Abstract

No content.

Description

Automatic Dehydration Control Circuit of Washing Machine

1 is a conventional washing machine dehydration circuit diagram.

2 is a dehydration motor and load and current characteristics.

3 is a diagram showing the change in operating current with dehydration time.

4 is a circuit diagram of the present invention.

* Explanation of symbols for main parts of the drawings

CT: Current transformer TD: Triac

PC: Photocoupler FF: Flip-flop

R ₁ , R ₂ , R ₃ . : Resistance I ₁ , I ₂ : Inverter

M: Motor OP ₁ to OP ₄ : OP Amplifier

D ₁ ~ D ₃ : Diodes CR ₁ , C ₁ ~ C ₆ : Condenser

Vcc: Power S ₁ : Push Button Switch

1: rectifier circuit 2: differential circuit

3: inverting amplifier 4: counter

5: oscillation circuit 10: operation current detector

20: comparison unit 30: control unit

The present invention relates to an automatic dehydration control circuit of a washing machine. In the dehydration administration of the washing machine, the manual dehydration time is set by the user, and in the automatic method, dehydration administration is performed during the dehydration period set in advance according to the washing stroke selected by the washing amount. It was a case that occurred. The present invention is to provide a circuit that can stop the dehydration motor by detecting when the dehydration is completed by the operating current of the dehydration motor in order to eliminate such problems, the current of the dehydration motor of the dehydration completion time In view of the fact that there is no change in characteristics, the sensing circuit for detecting the operating current of the dehydrating motor and the control circuit comparing the change rate of the detected operating current with the reference difference are configured to determine whether to supply the dehydrating motor. .

When described in detail by the accompanying drawings as follows. 1 is a conventional washing machine dehydration circuit is configured to supply the power of the dehydration motor (M) by the timer switch (TS), there is a disadvantage that can select the appropriate dewatering time according to the amount of laundry to be dewatered, There was a cause for unnecessary power consumption.

2 is a characteristic diagram of the load and current characteristics of the dewatering motor, which has the inherent characteristics of the induction motor in which the operating current increases as the load increases.In the dewatering motor, the change of the operating current according to the dehydration time is shown in FIG. There is a lot of moisture in the laundry, so the load is large, so the driving current flows a lot, but after a certain time after the completion of dehydration (t ₁ ), if the laundry is removed, it can be seen that a constant operating current (A) flows. The present invention detects such a driving current and stops the dehydration motor.

4 is a circuit diagram of the present invention, which is configured between an AC power source AC and a motor M in a dehydration control circuit in which an AC power source AC drives a dewatering motor M to perform a dewatering action. The driving current detector 10 configures the AC power source AC to drive the motor M through the current transformer CT and the triac TD, and then the driving current detected by the current transformer CT is the resistance R. FIG. ₆ ) and the rectifier circuit 1 composed of a diode (D ₁ ) and a capacitor (C ₆ ) is configured to be converted to direct current, and the comparison unit 20 passes the above-described operation through an OP amplifier (OP ₁ ) for a blower. The output of the current detector 10 is configured to be differentiated through a differential circuit 2 composed of a capacitor C ₁ , a resistor R ₁ , and an OP amplifier OP ₂ , and then resistors R ₂ (R ₃ ) and OP. The inverting amplifier 3 composed of the amplifier OP ₃ is configured to apply the comparative power supply Vo ₃ to the non-inverting (+) side of the OP amplifier OP ₄ , and the power supply Vcc is a distribution resistor R ₄ . (R ₅ The reference function Vo ' ₃ is applied to the inverting (-) side of the OP amplifier OP ₄ through) to perform the comparison function.

The control unit 30 outputs the counter 4 driven by the output of the oscillator circuit 5 composed of an inverter I ₁ , I ₂ , a resistor R ₄ , R ₅ , and a capacitor C ₄ . (Q) and the power supply (Vcc) passing through the pushbutton switch (S ₁ ) for starting dehydration are applied to the terminal (J) (K) of the flip-flop (FF), and the power supply (Vcc) is a differential element (C) ₃ ) and configured to be applied to the setting terminal S of the flip-flop FF through the resistor R ₁₀ and then the output of the flip-flop FF ( ) Is configured to control the triac (TD) through the bias resistor (R ₁₁ ) and the transistor (Q ₁ ) connected to the photocoupler (PC) to control the dehydration motor (M), but the comparison unit 20 ) Is controlled by the direction control diode (D ₂ ) (D ₃ ) and the resistor (R ₁₂ ) (R ₁₃ ) to control the clear terminal (CL) of the counter (4) so that the dehydration motor (M) automatically It is configured to be controlled.

Here, the capacitor C ₃ and the resistor R ₁₀ are for initial setting, and the reference numerals R ₈ and R ₉ are power distribution Vcc connected to the photocoupler PC.

Referring to the effect of the present invention configured as described above are as follows.

In the circuit diagram of FIG. 4, when power is initially applied, the power supply Vcc is differentiated through the capacitor C ₃ and the resistor R ₁₀ to apply “H. level” to the setting terminal S of the flip-flop FF. The output of the flip-flop (FF) (Q) ( Is applied to the output side of the flip-flop (FF). L. level is applied to the base side of transistor Q ₁ via bias resistor R ₁₁ to " turn off " transistor Q ₁ , and then to the gate side of triac TD. Since the driving power is not applied to the triac (TD) is "off", the driving of the dehydration motor (M) is stopped when the initial power is applied.

Here, when the spin start switch button S ₁ is turned "on", "H. level" is applied to the input side K of the flip-flop FF, so that the output shaft Q of the flip-flop FF ( ) Is applied to the output side of the flip-flop (FF). ) Was "H. level" a bias resistor (R _11), a transistor (Q ₁₎ by applying a high potential to the base side of the transistor ( "turn-on" the Q ₁₎ through the power supply (Vcc), a resistor (R ₈ of (R ₉ ) and the driving power is applied to the gate side of the triac (TD) through the photocapillar (PC) to turn on the triac (TD). As applied to M), the dewatering motor M having the same current torque characteristic as the second degree performs the dehydration process.

Then, the operating current change rate dildt of the dewatering motor M starts to decrease as shown in the third degree. At this time, the output voltage Vi induced by the current transformer CT can be expressed as Ki (where K is a constant) and is a rectifier circuit (1) consisting of a diode (D ₁ ), a resistor (R ₆ ), and a capacitor (C ₆ ). The output rectified at is the output power (Vo ₁ ) = Vi = Ki through the voltage follower (OP ₁ ), and its output is a differential circuit consisting of a capacitor (C ₁ ) and a resistor (R ₁ ) OP amplifier (OP ₂ ). When input to (2), output voltage (Vo ₁ ) =-R ₁ C ₁ = -R ₁ C ₁ K Output voltage inverted by an inverting amplifier (3) consisting of a resistor (R ₂ ) (R ₃ ) and an op amp (OP ₃ ) After outputting to the non-inverting (+) side of the OP amplifier (OP ₄ ) is applied to the comparison power supply and compared with the reference power supply (Vo ' ₃ ) applied through the resistor (R ₄ ) (R ₅ ).

Where comparative power This reference If it becomes larger, the output power Vo ₄ of the OP amplifier OP ₄ becomes the "H. level", and then the counter 4 is cleared through the diode D ₂ to continue to the input terminal J of the flip-flop FF. By applying the "L. level", the output of the flip-flop (FF) in the "H. level" ( ) Continues to drive the photocoupler (PC) through the transistor (Q ₁ ), so that the driving power is continuously applied to the triac (TD) can be dehydration of the motor (M). In other words, when the dehydration push button shake (S ₁ ) is "on", the dehydration motor (M) is driven by the control of the flip flow (FF) to perform the dehydration action and the OP amplifier (OP) that detects the state ₄₎ the output is controlled by a flip-flow (FF) via a counter (4) that will be performed to continue the dewatering action sikimeuroseo still drive the Motor (M) for the dehydration of.

However, dehydration is almost finished, so This reference If it becomes smaller, the output power Vo ₄ of the OP amplifier OP ₄ becomes " L. Level " and then is applied to the clear terminal CL of the counter 4 through the diode D ₂ to release the clear state. Accordingly, the function of the counter 4 is performed by the output of the oscillation circuit 5.

At the same time, as the "H.level" output of the counter 4 is applied to the input terminal J of the flip-flop FF, the output Q of the flip-flop FF ( ) Side "level H.""L.level" is applied, and wherein via a bias resistor (R ₁₁₎ to "L. level" is applied from the output side ( "t-18") of the flip-flop (FF) transistor (Q ₁ ) The transistor Q ₁ is " turned off " by applying a low potential to the base side, and then the photocoupler PC is " off ", so that the driving power at the gate side of the triac TD is cut off and dewatered. The dehydration is automatically terminated by shutting off the drive power of the motor (M).

That is, when the dehydration action is almost finished, the counter ₄ of the output of the OP amplifier OP ₄ having sensed the state is released, and then the output of the counter 4 driven by the output of the oscillation circuit 5 is flipped. By controlling the flop (FF) to stop the rotation of the dehydration motor (M) dehydration can be terminated automatically.

Therefore, in the related art, the dehydration motor is driven after setting the dehydration time using a mechanical timer. The user cannot set an appropriate dehydration time according to the amount of dehydrated laundry. Not only power consumption is generated, but inconvenience has occurred, but the present invention has the effect that the dehydration function can be performed or completed automatically regardless of the amount of dehydration since the motor is automatically stopped after dehydration is detected after the dehydration action is detected. . As described above, the present invention is configured so that the operation of the dehydration motor is detected and compared with a reference power source, and then the completion operation of the dewatering motor is automatically performed through a counter and flip-flop. Not only the trouble of selecting the dehydration time can be eliminated, but also inconvenience such as re-dehydration or extension of drying time due to insufficient dehydration can be eliminated. It is.

Claims (1)

In the laundry dehydration circuit consisting of a dehydration motor (M) for driving the dehydration container of the washing machine and a mechanical timer for applying power to the dehydration motor (M) for a set dehydration time between the power supply side and the dehydration motor (M). The rectifier circuit (1) consisting of a resistor (R ₆ ), a capacitor (C ₆ ), and a diode (D ₁ ) for the operating current connected to the current transformer (CT) and the triac (TD) to be sensed through the current transformer (CT). The output of the driving current detection unit 10 and the output of the driving current detection unit 10 which have passed through the voltage follower OP ₁ through the capacitor C ₁ , the resistor R ₁ , and the OP amplifier Differentiate through the differential circuit 2 composed of (OP ₂ ), and apply the comparison power supply (Vo ₃ ) to one side (+) of the OP amplifier (OP ₄ ) through the inverted amplification OP amplifier (OP ₃ ) and distribute The output of the counter 4 and the comparator 20 to which the reference power supply Vo ' ₃ is applied to the other side (-) of the op amp R ₄ through the resistors R ₅ and R ₄ to be compared. Power (Vcc) passing through power (Q) and pushbutton switch (S ₁ ) drives terminal (J) (K) of flip-flop (FF) and power (Vcc) causes capacitor (C ₃ ) and resistor ( The flip-flop FF is driven through the R ₁₀ to drive the setting terminal S to output the flip-flop FF. ) Drives the triac TD of the driving current detector 10 through the transistor Q ₁ connected to the photocoupler PC, but outputs the output diode D ₂ of the comparator 20. Automatic dewatering control circuit of the washing machine, characterized in that the control unit 30 is configured to control the counter 4 to control the dehydration function automatically.