KR100802468B1 - Ball balancer damage sensing apparatus and method - Google Patents

Abstract

A device and a method for sensing damage of a ball balancer of a washing machine are provided to detect whether the ball balancer is damaged by sensing the RPM of a motor in a dehydration process. A method for sensing damage of a ball balancer of a washing machine comprises the steps: comparing detected RPM of a motor to set RPM(S26); computing a phase duty by using voltage of pulse determined by rotation of the motor; and comparing the phase duty to set phase duty(S27); judging the damage of the ball balancer using a micro processor; and displaying state of the ball balancer(S30). The damage of the ball balancer is judged whether a predetermined phase duty is lasting for predetermined times. A device for sensing damage of a ball balancer has an RPM detector and the micro processor.

Description

Ball balancer damage sensing apparatus and method of washing machine

1 is a flow chart of a dehydration stroke during a washing stroke according to the prior art,

2 is a block diagram of a washing machine having a ball balancer according to an embodiment of the present invention,

3 is a flow chart of a ball balancer damage detection method during the dehydration stroke according to an embodiment of the present invention,

4 is an exemplary diagram of a pulse graph when a motor rotates to calculate a phase duty according to an exemplary embodiment of the present invention.

* Description of the symbols for the main parts of the drawings *

1: housing 2: tub

4: door 5: water pipe

6: detergent supply unit 7: drain pipe

8: rotary shaft 9: drive motor

10: drum 20: ball balancer

The present invention relates to a ball balancer damage detection device and method of the washing machine, and more particularly, when the rotation speed of the motor rotates more than the predetermined motor speed during the dehydration stroke during the washing stroke of the washing machine, the pager duty is a certain value or more The present invention relates to a ball balancer breakage detection device and method for a washing machine that prevents problems such as PL by determining that the ball balance is broken and stopping the dehydration stroke when the ball balance is maintained for more than the time.

In general, the washing machine washes the laundry by rotating the drum containing the laundry with the driving motor. In the washing process, the drum rotates at a low speed in the reverse direction of the forward direction, and in the dehydration process, the drum rotates at the high speed in the forward direction. While performing the dehydration (S13) stroke of draining the woven water (S12) while rotating (S11) and performing the bubble blowing (S14) stroke of releasing the entangled cetals.

However, during the dehydration process, the drum is rotated at a high speed in the state in which the laundry is not evenly distributed over the entire area of the drum, but is concentrated only on a specific part, or the drum is pushed to one side due to the rapid rotation of the drum during the initial dewatering process. When rotating at high speed, the center of gravity of the drum and the center of rotation do not coincide with each other, causing vibration and noise. If this phenomenon is repeated, components including the drum, the rotating shaft, and the driving motor may fail or shorten their lifespan.

In particular, the drum-type washing machine has a structure in which the drum in which the laundry is loaded is arranged horizontally so that the laundry is rotated at a high speed while the laundry is collected at the bottom of the drum by gravity during dehydration, so that the center of gravity and the center of rotation do not coincide with each other. This is very likely to cause vibration and noise. Therefore, a drum type washing machine and other drum type washing machines in which the drum is installed vertically are generally provided with a balancer for maintaining the dynamic balance of the drum.

The ball balancer of the washing machine uses a racer which is respectively installed on the upper and lower portions of the drum to maintain a dynamic balance when the drum rotates at a high speed, and a steel ball and viscous oil disposed freely in the racer. It is provided.

Therefore, when the drum rotates and the drum does not maintain a dynamic balance due to the unbalanced eccentric structure of the drum itself and the uneven distribution of the laundry in the drum, the steel ball compensates for this and the drum is dynamic. The balance can be maintained.

However, when the drum rotates at a high speed, the ball balancer also moves rapidly according to the rotational speed of the drum, thereby causing a problem that the ball balancer is damaged from the vibration or shock generated from such a movement.

As a result, the ball balancer may be damaged during dehydration, which may further cause problems such as damage to PL and products when the ball embedded in the balancer comes out.

The present invention has been made to solve the problems of the prior art as described above, the object of the present invention is to break after detecting the breakage of the ball balancer installed inside the washing machine to reduce vibration and noise during dehydration during the washing stroke Provided are a ball balancer breakage detection device and method for a washing machine that prevents damage to the PL and product by stopping the dehydration stroke at the time.

Another object of the present invention is to detect the breakage of the ball balance by detecting the rotational speed of the motor during dehydration to provide a ball balancer breakage detection device and method of the washing machine for the quick and accurate detection of breakage of the ball balancer.

Technical means according to the present invention for achieving the above object is a rotation speed detection sensor for detecting the rotational speed of the motor during the dehydration stroke; And a microcomputer that compares the motor speed detected by the rotation speed detection sensor with a predetermined predetermined rotation speed and calculates a phase duty of the motor to determine whether the ball balancer is damaged or not.

In order to achieve the above object, the technical method according to the present invention detects the rotational speed of the motor during the dehydration stroke, determines whether the rotational speed of the motor is more than a predetermined predetermined rotational speed, the rotational speed of the motor If the rotation speed is equal to or greater than, the phase duty of the motor is calculated to determine whether the predetermined value is equal to or greater than a predetermined value. If the phase duty of the motor is equal to or greater than the predetermined value, the generation time of the phase duty of the motor equal to or greater than the predetermined value is determined. It is determined whether the predetermined time or more, and if the predetermined time or more is performed to determine that the ball balancer damage.

According to the present invention, by providing a ball balancer in the washing machine, it is possible to suppress noise and vibration during dehydration, and to prevent breakage of the ball balancer to prevent secondary damage and PL (Product Liability) problem. can do.

Hereinafter, preferred embodiments of the present invention will be described in detail with reference to the accompanying drawings.

2 is a cross-sectional view showing a schematic structure of a drum washing machine according to an embodiment of the present invention.

As shown, the washing machine according to the present invention is rotatable in the housing (1) forming the exterior, the tub (2) is installed inside the housing (1) containing the wash water, and the tub (2) And a drum 10 arranged to be loaded with laundry, and a door 4 hinged to an open front surface of the housing 1.

In the upper part of the tub 2, a water supply pipe 5 for supplying washing water and detergent to the tub 2 and a detergent supply device 6 are disposed, and in the lower part of the tub 2, when the washing operation of the laundry is completed, the tub ( A drain pipe 7 for discharging the wash water contained in 2) to the outside of the housing 1 is installed.

The rear side of the drum 10 is disposed such that the rotary shaft 8 extends through the rear of the tub 2, and a drive motor 9 to which the rotary shaft 8 is coupled is installed outside the rear side of the tub 2. Accordingly, when the driving motor 9 is operated, the rotating shaft 8 rotates to rotate the drum 10 together.

A plurality of dehydration holes (10a) is formed on the circumferential surface of the drum (10), during the washing process, water contained in the tub (2) flows into the drum (10) and washes with water in which detergent is dissolved. In the dehydration stroke, the water can be drained out of the housing 1 through the drain pipe 7.

A plurality of lifters 10b are disposed in the drum 10 in the longitudinal direction, and as the drum 10 rotates at a low speed during washing, the water-soaked laundry is pulled upward from the bottom of the drum 10. It is dropped back to the bottom of the drum 10 so that the laundry can be washed effectively.

Therefore, in the washing stroke, the rotating shaft 8 rotates in a reverse direction from the forward direction by the driving motor 9 to wash the laundry by rotating the drum 10 at low speed, and in the dehydrating stroke, the rotating shaft 8 rotates in one direction. The laundry is dehydrated by rotating the drum 10 at a high speed while rotating.

When the drum 10 rotates at a high speed in the dehydration process, the drum 10 itself is not made to coincide with the center of gravity or the center of rotation, or the laundry is not evenly distributed in the drum 10, and the drum is placed in a specific area. 10) fails to maintain a dynamic balance.

In order to prevent such dynamic unbalance, the ball balancer 20 is installed at the front and rear ends of the drum 10 so that the drum 10 can be rotated at a high speed while the rotation center and the center of gravity are matched.

The front of the housing 1 is provided with a control panel unit and a display unit for setting the washing stroke, the inside of the drive motor, pump, steam, detergent supply device, door, feed valve and A microcomputer is further provided to control an operation such as a drain valve and to control the display unit to display the washing stroke.

Here, the microcomputer has the detection data of damage detection of the ball balancer, that is, the predetermined rotation speed of the motor, the constant value (Vref) and the predetermined time (Tref) of the phase duty (PD), which are used as reference when dehydration is set in advance. If the rotational speed of the motor is input during dehydration, it is compared with the set predetermined rotational speed, and the phase duty value of the motor is calculated to determine whether the predetermined value (Vref) is greater than or equal to the predetermined value (Tref). It is determined whether the ball balancer is damaged by determining whether the ball balancer is damaged, and if it is determined that the ball balancer is damaged, the display unit is controlled to indicate that the ball balancer is broken so that the user can visually identify it.

3 is a flow chart of a ball balancer damage detection method of a washing machine according to an embodiment of the present invention will be described with reference to FIG.

The user supplies power to the washing machine, opens the door 4, loads laundry, and inputs a washing instruction through the control panel.

Thereafter, the microcomputer sequentially applies washing signals to various loads, such as a motor and a valve, according to a washing instruction input by a user and a preset washing algorithm to sequentially perform washing, rinsing, or dehydration.

While performing the washing stroke, the microcomputer determines whether to enter the dehydrating stroke, and when entering the dehydrating stroke, instructs the driving of the motor to perform the spin (S21) operation of the drum, and drains the water woven from the laundry by the spin operation. Perform the drain (S22) stroke to be discharged to the outside through).

Thereafter, the microcomputer performs a defoamer (S24) stroke for releasing the tangled laundry by the dehydration (S23) stroke and the dehydration stroke while accelerating the motor, and dewatering for a time set by the user or a time preset by the washing algorithm. Perform the administration.

During this dehydration stroke, the microcomputer continuously detects the balance by detecting the rotational speed of the motor (S25).

That is, the microcomputer determines whether the detected rotational speed of the motor is equal to or greater than a predetermined predetermined rotational speed (about 450 RPM) (S26).

Here, the predetermined rotational speed means the rotational speed at which the ball balancer can be damaged because the ball balance is damaged 20 and the ball inside the ball balance is ejected to the outside only when the rotational speed is greater than or equal to the predetermined rotational speed.

If the detected rotation speed of the drive motor 9 is equal to or greater than the predetermined rotation speed, the microcomputer calculates the phase duty value of the motor. In addition, the motor here is a DC motor.

That is, the phase duty PD of the motor is calculated by PD = Phase x Duty (voltage) x α (constant).

Here, the phase duty value is increased when the motor is heavily loaded. In this case, when the ball of the ball balancer 20 is pinched between the tub 2 and the drum 10, the load of the driving motor 9 becomes large. The phase duty value becomes large.

Accordingly, it is determined whether the calculated phase duty is greater than or equal to a predetermined value by comparing the calculated phase duty of the motor with a predetermined value Vref of the preset phase duty (S27).

Next, if the calculated phase duty is greater than or equal to a certain value, it is determined whether the time for which the phase duty is greater than or equal to a predetermined value is greater than or equal to a preset predetermined time (Tref = about 5 seconds) (S28), and the phase duty is greater than or equal to a predetermined value. If the time is more than a predetermined time (approximately 5 seconds), it is determined that the ball of the ball balancer is out of the prescribed orbit and went out to the outside between the tub and the drum, that is, the microcomputer determines that the ball balance 20 is broken. And stop dehydration.

In more detail, as shown in FIG. 4, a pulse signal composed of an on / off signal is generated according to the rotation of the motor.

Accordingly, when dehydration, a pulse of a normal motor rotation generates a pulse having a constant duty ratio (Ton = A, B) having a constant voltage value (Vref). When a load is generated in the motor, the voltage value and duty ratio (Ton = D) will change.

Therefore, the microcomputer calculates the phase duty by calculating the voltage value of the on-cycle phase (a, b, c, d) of the pulse of one cycle, compares the calculated phase duty with a predetermined constant value (Vref), When the phase duty exceeds a predetermined value, the time of the phase duty exceeding the predetermined value is checked and it is determined whether the predetermined time Tref is generated.

That is, as shown in FIG. 4, the intervals of the on period having the phase duty exceeding the predetermined value Vref are c and d, and the occurrence time of the phases c and d of the on period is compared with the constant time Tref. do. If it is determined that only d on the next on cycle has occurred for a predetermined time period, it is determined that the ball balance is broken on the on cycle d of the plurality of pulses.

Next, the motor is stopped to end the spin operation (S29), and the display unit is controlled to display the damage of the ball balancer through the display unit (S30).

Here, the method of displaying the damage of the ball balancer, it can be displayed by the character display through the LCD window or by turning on / off the lamp such as LED.

In this way, by providing a ball balancer in the washing machine, noise and vibration can be suppressed during dehydration, and damage of other parts can be prevented and PL problems can be prevented by detecting breakage of the ball balancer.

The present invention is not limited to the above-described embodiments, and various changes can be made by those skilled in the art without departing from the gist of the present invention as claimed in the following claims.

As described in detail above, the present invention can suppress the noise and vibration during dehydration by providing a ball balancer in the washing machine, and by preventing the damage of the ball balancer to prevent secondary damage of other parts and PL (manufacturer responsible: Product Liability) can be prevented.

In addition, by detecting the rotational speed of the motor, and to determine the damage detection of the ball balancer according to the detected rotational speed and accurate determination of the damage of the ball balance, there is an economic advantage because no additional equipment is provided.

Claims (7)

A rotation speed detection sensor detecting a rotation speed of the motor during the dehydration stroke; And Comparing the detected motor rotational speed with a predetermined predetermined rotational speed, calculating a voltage value of an on-period pulse from a pulse of one cycle according to the motor rotation, calculating a phase duty, and comparing a predetermined constant value with a ball balancer. Ball balancer breakage detection device of a washing machine comprising a microcomputer to determine whether the breakage. The method of claim 1, The ball balancer breakage detecting apparatus of the washing machine, further comprising a display unit which displays whether the ball balancer is broken according to the instruction of the microcomputer. The method of claim 1, wherein the microcomputer And determining whether the ball balancer is damaged by determining whether the phase duty of a predetermined value or more is maintained for a predetermined time or more when the phase duty is greater than or equal to a predetermined value. Detect the rotational speed of the motor during the dehydration stroke, It is determined whether the rotation speed of the motor is greater than or equal to a predetermined predetermined rotation speed, When the rotation speed of the motor is equal to or greater than the predetermined rotation speed, a phase duty is calculated by calculating a voltage value of an on-cycle pulse from a pulse of one cycle according to the motor rotation, It is determined whether the phase duty is greater than or equal to a predetermined value, If the phase duty of the motor is equal to or greater than the predetermined value, it is determined whether the generation time of the phase duty of the motor, which is equal to or greater than the predetermined value, is equal to or greater than a predetermined predetermined time, Ball balancer damage detection method of the washing machine characterized in that it is determined that the ball balancer damage when the predetermined time or more. The method of claim 4, wherein the ball balance is broken Ball balancer damage detection method of the washing machine characterized in that the end of the spin operation of the washing machine. The method of claim 4, wherein the ball balance is broken The ball balancer breakage detection method of the washing machine, characterized in that for indicating the breakage of the ball balance through the display. The method of claim 4, wherein the constant speed of the motor is The ball balancer damage detection method of the washing machine, characterized in that the minimum number of revolutions of the ball balancer.

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