JPH067584A - Washing machine controller - Google Patents

Abstract

(57) [Abstract] [Purpose] When an abnormality occurs in the stirring blade drive system (particularly the motor drive system), the rotation detection function of the cloth amount sensor is used to detect a failure and shut off the power supply to the motor. The purpose is to prevent the laundry from being damaged and the motor from smoking and igniting. [Structure] A condenser motor that drives a stirring blade arranged at the bottom of a washing tub, a motor control unit that controls energization of this motor, a rotation speed detection unit that detects the rotation speed of the motor, and a rotation speed detection unit of this rotation speed detection unit. Output pulse of the motor O
A count unit that counts the N period and the OFF period separately is provided, and when the number of OFF period pulses within a predetermined period exceeds a predetermined value, energization to the motor is cut off, thereby making it possible to prevent the occurrence of abnormal operation. It is possible to obtain a washing machine that prevents smoke and ignition from the motor.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a washing machine controller having a cloth amount detecting function.

[0002]

2. Description of the Related Art In recent years, washing machines have been automated, such as determining the amount of laundry put into a washing tub and determining the washing time and the number of times of rinsing based on the amount of laundry to operate. .

For example, as disclosed in Japanese Patent Laid-Open No. 59-139298, when the washing operation is started, after a predetermined water level is supplied to the washing tub, the stirring blade is intermittently rotated for a predetermined time to stir at this time. Detecting the rotation speed of the wing to determine the amount of cloth,
A washing machine control device that determines the water level during rinsing has been proposed.

Further, as disclosed in Japanese Patent Application Laid-Open No. 62-176491, a washing machine has been proposed which performs water supply control and water flow control in accordance with the amount of cloth by increasing the accuracy of determining the amount of cloth. There is.

In any case, the number of revolutions of the stirring blade for a predetermined period is detected as the number of pulses, and if the number of pulses is small (the load is large), it is judged that the amount of cloth is large, and if the number of pulses is large, it is judged that the amount of cloth is small. Based on the result of the determination, the subsequent processes are operated.

The operation of the conventional washing machine will be described below with reference to FIG. FIG. 5 is a flowchart showing an operation from the time when the laundry is put into the washing machine to the time when the laundry is started.

First, load laundry (step 41),
When the start button is pressed (step 42), the motor rotates (step 43) to start sensing, and the rotation number attached to the motor detects the number of revolutions as a pulse number (step 44). 45
Is compared with a predetermined value A _1, and if N <A _1, it is determined that the amount of cloth is large (step 46). If N ≧ A ₁ , the process proceeds to step 47, where it is compared with a predetermined value A ₁ <A _2, and A ₁ If ≦ N <A _2, it is determined that the amount of cloth is medium (step 48), and if N ≧ A ₂ , it is determined that the amount of cloth is small (step 49), and water is supplied to the predetermined level in steps 50 to 55, respectively. Proceeding to step 56, stirring is started, and thereafter washing, rinsing and dehydration are performed.

[0008]

[Problems to be Solved by the Invention]
With the conventional configuration, even if the number of pulses N is extremely large, N ≧ A
₂There is a condition of, and only a small amount of cloth is judged. Pa
The case where the number of looses is extremely large is (1) Motor and stirring
The connection of the power transmission mechanism between the blades becomes loose and
When the influence of the heavy load does not appear on the motor (2)
The two electric currents applied to the main and auxiliary windings of the sensor motor.
2 if one of the forces is continuously energized or irregularly energized
There are two cases. In the former case, washing is not done
There is a problem. In the latter case, the continuous rotation of the stirring blade
In addition to the problem that the laundry will be kinked and will
May cause smoke and fire.

This will be described in more detail with reference to FIG. (A) shows the electric power applied to the main winding of the condenser motor, (b) shows the electric power applied to the auxiliary winding, and the cross-batch portion is the electric power application period. That is, in the main winding, the period of (b),
Power is applied to the sub winding for the period (d), and the other periods (a), (c), and (e) are periods in which no power is applied. So in this case the motor is
It means that it is operating normally: (a) Stop (b) Rotate right (c) Stop (d) Rotate left (e) Stop.

By the way, the power applied to the sub winding is (C)
4), that is, when the bidirectional thyristor for controlling the power applied to the auxiliary winding is short-circuited, the motor rotates continuously to the left, causing the inconvenience described in (2) above and As can be seen from (a) and (c),
During the period of (b), in addition to the current flowing in the sub winding, a current equivalent to that when the motor is locked flows in the main winding, causing the motor to remarkably generate heat. If such a thing is repeated, smoke and ignition will occur.

The present invention solves the above-mentioned problems of the prior art. When the number of pulses from the rotation detecting section becomes extremely large, this phenomenon is accurately detected, and the energization of the motor is stopped to bring about the foregoing. The purpose is to prevent inconvenience and fire accident.

[0012]

To achieve this object, the means of the present invention comprises a condenser motor for driving a stirring blade, a motor control unit for controlling energization of the motor, and a rotational speed of the motor. A rotation speed detection unit,
The number of output pulses of the rotation speed detection unit is set to the ON period during which power is supplied to the motor and the power is cut off during the ON period.
A counting unit that counts by dividing into FF periods and a cloth amount determining unit that determines the amount of cloth based on the output of the counting unit are provided. The cloth amount determining unit determines the amount of cloth based on the number of pulses, and counts the amount of cloth. When the number of pulses in the OFF period of the unit exceeds a predetermined value, the motor is de-energized to notify the abnormality.

[0013]

The operation of this configuration will be described below, in which the number of pulses in a normal state and the number of pulses in an abnormal state can be clearly divided and can be immediately dealt with.

FIG. 3 is an explanatory diagram of the relationship between the drive command of the motor and the pulse number of the rotation detecting section corresponding thereto. The horizontal axis indicates the passage of time. (A) shows a motor drive command issued from the control device in time series. First, when the power is turned on and the start switch is pressed after the period (a) has elapsed, the control device rotates clockwise for the period (b), (c)
The command of the period rest, the period left rotation in (d), and the period rest in (e) are issued. On the other hand, if everything is normal, the rotation detector outputs the pulse of (b) when the amount of cloth is large and the pulse of (c) when the amount of cloth is zero. In the figure, the area indicated by the vertical thin line is the pulse number during the motor ON period, and the area indicated by the diagonal line is the pulse number during the motor OFF. Since the number of pulses when the motor is off is due to the inertial rotation of the motor, it has a characteristic of exponentially decreasing and abruptly decreasing as the load amount increases.

Next, when there is an abnormality in the driving force transmission system between the motor and the stirring blade, for example, when the belt connecting the motor and the speed reducer is loosened or disengaged, the motor load becomes extremely light, so inertia The rotation becomes longer and the number of pulses in the OFF period increases as shown in (d). In addition, turning on and off the power supplied to the main and sub windings of the condenser motor
When either one of the two bidirectional thyristors performing the above is short-circuited, the unidirectional continuous rotation is performed, so that the pulse number has no difference between ON and OFF as shown in (e).

Comparing the pulse numbers of (b) to (e) above, there is a clear difference between the normal time and the abnormal time in the motor OFF period, and the pulse numbers are closest to each other (c) and (d). Even between can be sufficiently distinguished.
Therefore, by counting the number of pulses in the OFF period with the above-described configuration, it is possible to easily distinguish between normal and abnormal, and to prevent the cloth from being turned off and smoke and ignition accidents from the motor. Further, the OFF period is generally about 0.5 seconds to 1.5 seconds, but the above normal / abnormal determination is possible even with the number of pulses of a time of less than 0.5 seconds.
If it is explained in (3), it is possible to judge normal / abnormal only during the period of (c) or a part of it, and the power can be turned off before entering the period of (d), so only the prevention of smoke and ignition of the motor. In addition, it is possible to prevent simultaneous conduction of two bidirectional thyristors that control the electric power of the main winding and the sub winding of the motor, and also has a protection function for the bidirectional thyristors.

[0017]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 1, the washing tub 2 is arranged in the outer tub 1,
A stirring blade 3 is rotatably arranged on the inner bottom of the washing tub 2. At the outer bottom of the outer tub 1, a speed reducer 4 that decelerates and transmits the rotation of the motor 5 to the stirring blade 3 is provided. Motor 5
Has a main winding 5a and a sub winding 5b, a capacitor 6 is arranged on the input terminal side of these two windings, and is turned on / off by the bidirectional thyristor 7a and the bidirectional thyristor 7b of the motor drive unit 7. Controlled. The number of rotations of the motor 5 is detected by the rotation detection unit 8, and its output pulse is output by the control device 1.
It is input to the counting unit 10a which is a part of 0. The notification unit 9 is arranged on the upper part of the housing (not shown) to notify the abnormal state. The control device 10 controls the entire washing machine. The configuration of the functions related to the present invention in the control device 10 will be described below. The counting unit 10a counts the pulse signal from the rotation detection unit 8 into a predetermined period by dividing the motor drive command signal into an ON period and an OFF period, and inputs the count result to the cloth amount determination unit 10b. The cloth amount determination unit 10b compares the number of pulses during the OFF period with a predetermined value prepared for the cloth amount determination to determine the cloth amount, and the main control unit 10b.
In addition to feeding back to c, comparing with a predetermined value prepared for abnormality detection, if it exceeds, it causes the notification unit 9 to notify the abnormality, and also feeds back to the main control unit 10c to stop energizing the motor. Let The main control unit 10c manages the coordination and timing between the functional units in the control device 10.

Regarding the embodiment configured as described above,
The operation will be described mainly with reference to FIG. 2 and with reference to FIG.

First, when laundry is put into the washing tub 2 (step 21) and a start switch (not shown) for starting operation is pressed (step 22), based on a drive command from the motor controller 10d. The bidirectional thyristors 7a and 7b of the motor drive unit 7 are alternately opened and closed to rotate the motor 5 left and right (step 23), and the stirring blade 3 is driven via the speed reducer 4. The number of revolutions of the motor 5 which is affected by the laundry hitting the stirring blades 3 is detected by the number of revolutions detector 8 (step 24), and the output pulse is sent to the counter 10a and turned off within a predetermined period. The number of period pulses is counted (step 25). The pulse number N in the OFF period is compared with the pulse number X ₁ prepared for abnormality detection in the cloth amount determination unit 10b (step 26).
If N <X _1, it is judged to be normal and the process proceeds to step 27, where the amount of cloth is judged by comparing it with the predetermined value used for judging the amount of cloth. Is supplied to a level suitable for, and the process proceeds to washing, rinsing, and dehydration. The above is the operation when all are normal.

By the way, if N> X ₁ in step 26, that is, if the number of pulses in the OFF period exceeds a predetermined value prepared for abnormality detection, it is determined that the stirring blade drive system has failed (step 30), and immediately the motor control is performed. The motor power is turned off (step 31) in response to a command from the section 10d to prevent the cloth from becoming dirty and the motor from smoking and igniting, and the notification section 9 reports an abnormality (step 32). In this way, when the agitating blade drive system fails, it is possible to prevent the laundry from being messed up, and to prevent the motor from smoking or igniting. Further, in the configuration of the embodiment, since the abnormality determination can be performed in a very short time, the bidirectional thyristor 7
Simultaneous conduction of a and 7b is prevented, and a thyristor protection function is also provided.

In this embodiment, the operation of detecting the cloth amount without water is described, but it goes without saying that the cloth amount may be detected by adding water. Further, although the cloth amount detection is performed using only the pulse number in the OFF period, it may be used in combination with the pulse number in the ON period. Further, it goes without saying that this detection method can be utilized not only when detecting the amount of cloth but also when washing and rinsing.

[0023]

As described above, according to the present invention, the number of pulses for detecting the number of rotations of the motor is divided into the motor ON period and the OFF period and counted, and the OFF period pulse number of the predetermined period is compared with the predetermined value to obtain the stirring. Since the failure of the wing drive system can be reliably determined in a short time and the motor power can be shut off, it is possible to prevent the laundry from being damaged by continuous rotation in the event of abnormalities, and to prevent the motor from smoking and igniting. By preventing simultaneous conduction, it is possible to protect the bidirectional thyristor.

[Brief description of drawings]

FIG. 1 is a configuration diagram of an embodiment of the present invention.

FIG. 2 is a flowchart for explaining the operation in the embodiment of the present invention.

FIG. 3 is a diagram for explaining the relationship between a motor drive command and the number of rotation detection pulses according to the present invention.

FIG. 4 is a diagram for explaining the problems of the conventional example.

FIG. 5 is a flowchart for explaining the operation of the conventional example.

[Explanation of symbols]

 1 Outer tub 2 Washing tub 3 Stirring blade 4 Reducer 5 Motor 6 Condenser 7 Motor drive part 8 Rotation detection part 9 Notification part 10 Control device

Claims (1)

[Claims] Claim: What is claimed is: 1. A condenser motor for driving a stirring blade disposed at the bottom of a washing tub, a motor control unit for controlling energization of the motor, a rotation speed detection unit for detecting the rotation speed of the motor, and the rotation speed. A count unit that counts the number of output pulses of the detection unit by dividing it into an ON period in which power is supplied to the motor and an OFF period in which power is cut off, and a cloth that determines the cloth amount based on the output of this count unit. The cloth amount judging means judges the cloth amount based on the number of pulses, and when the number of pulses in the OFF period of the counting unit exceeds a predetermined value, the energization of the motor is stopped and the abnormality is notified. A control device for the washing machine that is configured.