JP4983579B2 - Drum washing machine - Google Patents

Description

  The present invention provides a drum-type washing machine including a vibration detection device that detects vibrations in a plurality of directions of a water tank. The difference in resonance dehydration rotational speed of each axis obtained from the vibration detection device in a resonance region is as follows. Accordingly, the present invention relates to a drum-type washing machine that switches a threshold value used for determining whether or not to shift to high-speed rotation.

  In order to achieve low vibration dewatering in the dehydration process of the drum type washing machine, the issue is how to make the laundry evenly stick to the inner wall of the drum and shift to high speed dewatering with little unbalance. In the past, many washing machines have been proposed that detect the magnitude of imbalance based on the output result obtained from the vibration detection device provided in the water tub or casing and determine whether to shift to high-speed dewatering. Further, a washing machine has been proposed that specifies the position of the unbalance and realizes low vibration dewatering in addition to the determination of shifting the specified result to high speed dewatering.

  For example, a drum-type washing machine has been proposed in which the degree of unevenness of the clothing in the direction of the rotation axis is specified by two vibration detection devices attached to a water tank, and dehydration rotation control is performed based on the specification result (for example, a patent) Reference 1).

In addition, vibration detection means that can detect vibrations in multiple directions of two or more axes, identifies the unbalance position in the front-rear direction of the clothing from the difference in phase angle of each vibration component, and performs high-speed dehydration according to the unbalance position There has been proposed a drum-type washing machine that individually sets the reference value of the determination means that shifts to (see, for example, Patent Document 2).
Japanese Patent No. 3865791 JP 2006-311885 A

  However, since the conventional configuration (Patent Document 1) requires two vibration detection devices in order to specify the degree of bias, it is not desirable because it increases the cost of the equipment.

  Further, in the configuration of Patent Document 2, depending on how the laundry is biased, the maximum value detection timing of each vibration component is greatly shifted, making it difficult to obtain the phase angle difference, and specifying an accurate unbalanced position. I had a problem that I could not.

  In addition, the unbalanced position is not limited to simply the front-rear direction, but there is a case where one side is biased toward the front side and the other side is biased toward the rear side. There was a problem that it was not possible to specify only by the difference of.

  The present invention solves the above-described conventional problems, and identifies the degree of unevenness of clothing that increases vibration from the magnitude of the difference in the resonance dehydration rotational speed, thereby realizing efficient imbalance determination. An object of the present invention is to provide a drum type washing machine with low vibration and low noise.

  In order to solve the above-described conventional problems, a drum-type washing machine of the present invention includes a drum provided with a water passage hole on the outer periphery, a water tank that encloses the drum and stores washing water, a motor that rotationally drives the drum, A housing that houses the aquarium, a vibration-damping damper that is attached between the aquarium and suppresses vibrations of the aquarium, a vibration detector that detects vibrations in a plurality of directions provided in the aquarium, and a vibration detector An unbalance detection means for detecting the unbalance amount of the laundry according to the output, the unbalance detection means is a difference between the resonance dehydration rotational speed at which the output peak of each axis obtained from the vibration detection device appears. According to the size, the threshold used for the subsequent determination of imbalance detection is switched.

  The drum type washing machine of the present invention can perform accurate imbalance determination according to the unbalanced state of the laundry, and can realize low vibration and low noise dehydration.

  A first invention includes a drum provided with a water passage hole on the outer periphery, a water tank that encloses the drum and stores washing water, a motor that rotationally drives the drum, a housing that houses the water tank, a water tank and a housing An anti-vibration damper that is installed in between to suppress vibrations in the aquarium, a vibration detection device that detects vibrations in multiple directions, and detects the unbalanced amount of laundry according to the output of the vibration detection device. The unbalance detection means for determining imbalance detection according to the magnitude of the difference in the resonance dehydration rotational speed at which the output peak of each axis obtained from the vibration detection device appears. By switching the threshold to be used, if the unbalanced state does not significantly increase vibration during dehydrating high-speed rotation, it shifts to further high-speed rotation, and in the case of an unbalanced state that leads to large vibration. It is possible not only to reduce the vibration caused by unbalance, but also to reduce unnecessary retry processing and shorten the operation time. It becomes possible.

  According to a second invention, in the first invention, the smaller the difference between the resonance dehydration rotational speeds of the respective axes, the smaller the threshold used for the determination of imbalance detection, so that a large vibration occurs when shifting to high speed dewatering. The presumed state can be detected in advance, and high-speed dehydration with low vibration and low noise can be realized, and the safety of the product can be improved.

  According to a third invention, in the first or second invention, the unbalance detection is performed after passing through the resonance region, so that the threshold used for the unbalance detection is determined based on the unbalance characteristic result detected in the resonance region. It is possible to switch, and it is possible to perform imbalance detection with high accuracy.

  4th invention is the drum which provided the water flow hole in the outer periphery, the water tank which encloses a drum and stores washing water, the motor which rotationally drives the drum, the control means which controls the drive of the motor, and the water tank A vibration storage device that is attached between the water tank and the water tank to suppress vibration of the water tank, a vibration detection device that detects vibrations in multiple directions provided in the water tank, and an output of the vibration detection device And an unbalance detecting means for detecting the unbalance amount of the laundry according to the control means, the control means according to the magnitude of the difference in the resonance dehydration rotational speed at which the output peak of each axis appears from the vibration detecting device. Therefore, by controlling the rotation speed during steady dehydration, it is possible to reduce the dehydration rotation speed based on the results of output characteristics in multiple directions of the vibration detection device in the resonance region, which is determined to be highly likely to cause large vibration during steady dehydration. Complement to the rotation speed Without continuing the dewatering operation, generating an increase in operation time due to rework dehydrated activated by, and low vibration can be realized dehydration of low noise.

  According to a fifth aspect of the present invention, in the fourth aspect of the invention, the smaller the difference between the resonance dehydration rotational speeds of the respective axes, the lower the rotational speed during steady dehydration, whereby the vibration is likely to increase during steady dehydration. Even in the state, vibration and noise during steady dehydration can be suppressed.

  In a sixth aspect based on any one of the first to fifth aspects, the vibration detection device is an acceleration sensor capable of detecting acceleration in three directions, and the first direction is orthogonal to the second direction. And a horizontal direction, the second direction coincides with the rotation axis direction of the drum, and the third direction is orthogonal to the first direction and also orthogonal to the second direction. It is possible to accurately determine the movement of the.

  According to a seventh invention, in any one of the first to sixth inventions, the vibration detection device can perform vibration detection with high sensitivity by providing the vibration detection device at a front portion in the rotation axis direction at an upper peripheral portion of the water tank. it can.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that the present invention is not limited to the present embodiment.

(Embodiment 1)
FIG. 1 is a block diagram of a control device that suppresses vibration due to unbalance of the laundry of the drum-type washing machine according to the first embodiment of the present invention. In FIG. 1, 10 is a housing, 11 is a drum for storing and rotating laundry, and 12 is a motor for rotating the drum while controlling its speed. 13 is a water tank that encloses the drum 11 and stores water, 18 is a cover having a laundry inlet, 14 is a seal packing for connecting the water tank 13 and the cover 18 having the laundry inlet without a gap, 15 A support spring 16 for holding the posture of the water tank 13 is a vibration isolating damper for reducing vibration generated when the motor rotates to reduce vibration transmission to the housing 10 and the floor.

  Reference numeral 17 denotes a vibration detection device that detects the vibration of the water tank 13. As an example of the vibration detection device, an acceleration sensor capable of outputting a change in acceleration as a voltage change is used in the present embodiment.

  The acceleration sensor in the present embodiment uses a piezoresistive acceleration sensor having a relatively simple structure. In addition, the acceleration sensor in the present embodiment employs a sensor capable of detecting three axes, detects vibrations in a plurality of directions, and accurately captures the movement of the aquarium that performs complex behavior in the dehydration resonance region, It is possible to detect various unbalanced states. However, the acceleration sensor may be biaxial.

  The attachment position of the vibration detection device 17 in the present embodiment is the upper front side of the water tank. Since the vibration when shifting to high-speed rotation with the unbalance of the laundry in the drum in the front part is larger than that in the rear part, high-speed rotation with a large unbalance in the front part It is necessary to avoid accelerating as much as possible. If the front part is unbalanced, the water tank shakes easily on the front side, so it is desirable that the vibration detector is attached to the front part.

  Reference numeral 19 denotes an anti-vibration rubber for installing the housing 10 on the floor, and the support spring 15 and the damper 16 constitute support means. Further, 20 is an unbalance detection means for detecting an unbalance according to the output of the vibration detection device, and 21 is a control means for controlling the rotation of the motor 12.

  FIG. 2 is a graph of a drum rotation control pattern in the first embodiment of the present invention. Immediately after the start of the dehydration process, a loosening process is performed to loosen the entanglements and lumps of the laundry and to make the clothes easily adhere to the inner peripheral surface of the drum. After that, before reaching the resonance region, several stages of preliminary unbalance detection are performed to detect a certain degree of imbalance in advance and temporarily stop dehydration (first and second imbalance detection sections). Thereafter, in the resonance region (140 to 280 rpm), the difference in the resonance dehydration rotational speed at which each output peak of the three-axis acceleration sensor appears is calculated, and the calculation result is determined in the subsequent unbalance detection (third unbalance detection section). Used for threshold correction.

  FIG. 3 is a flowchart showing a series of processes for calculating the resonance dehydration rotational speed difference and performing an unbalance determination based on the calculation result.

  When the start of the resonance range (140 rpm) is reached, in step 3, the amplitude in three directions is calculated from the output value for each axis of the triaxial acceleration sensor and the drum rotation speed at that time, and the rotation speed and amplitude are calculated. Remember. The amplitude (X) can be calculated from the following equation.

X = a ÷ (2πf) ² [m]
a [m / s ² ] ... acceleration, f [Hz] ... rotational frequency After that, the output of the acceleration sensor is acquired at a sampling period of 1 [msec] until it passes through the resonance range, and in each direction each time Perform amplitude calculation. When the calculated amplitude exceeds the stored amplitude, the stored amplitude and the rotational speed at that time are updated. This process is performed until the resonance frequency is exited (280 rpm), and the resonance dehydration rotation speed in each direction (R1 [rpm] in the first direction, R2 [rpm] in the second direction, and R3 [rpm] in the third direction) Confirm).

  In step 5, the total difference (A [rpm]) is calculated from the determined resonance dehydration speed in each direction. In this embodiment, the sum of differences of all combinations between directions is calculated by the following formula.

A = ‖R1-R2‖ + ‖R2-R3‖ + ‖R1-R3‖
These combinations are not all combinations, but may be differences between specific directions.

  In the unbalance determination section provided after passing through the resonance region, the unbalance amount is detected, and whether or not to shift to high-speed dewatering is determined. In the present embodiment, the unbalance determination after passing through the resonance region is performed using 300 [rpm] as the unbalance detection section (step 6). Here, a predetermined threshold set for determining whether or not to shift to the high-speed dewatering is switched according to the total difference (A [rpm]) of the stored resonance dewatering rotation speed.

  That is, the Peak to Peak value (Vpp “mV”) of the acceleration sensor output voltage is measured, the output sampling and the Vpp are updated every 1 [msec], and the comparison judgment of Vpp and the threshold is performed. The threshold value for comparison with Vpp is switched according to the value of A.

  For example, when A is 20 [rpm] or more, the vibration is not so much deteriorated during steady dehydration rotation, and thus the threshold value is relaxed. On the other hand, if A is less than 10 [rpm], it is an unbalanced state in which vibration during steady dehydration rotation deteriorates. As a result, the vibration level in each direction output from the acceleration sensor at the time of unbalance determination does not change much, but by determining that the balance is in a state where the vibration increases during steady dehydration, the vibration level during steady dehydration is increased. Can be prevented.

  4 and 5 show the output from the three-axis acceleration sensor in the vicinity of the resonance region when the laundry of 6 kg capacity is dehydrated using the drum type washing machine of 9 kg of dewatering capacity.

  FIG. 4 shows the output when the difference between the three-axis resonance dehydration rotation speed is large, and FIG. 5 shows the output when the difference between the three-axis resonance dehydration rotation speed is small. 4 and 5, there is no difference in the vibration level at the time of resonance, but it can be confirmed that the output of the acceleration sensor during steady-state dehydration is significantly increased in FIG. 5 where the difference in rotational speed is small. It was.

  FIG. 6 shows the difference in resonance dehydration rotation speed when the laundry having a capacity of 6 kg is dehydrated using the same machine as FIGS. 4 and 5, the output result of the acceleration sensor at the time of imbalance determination, and the steady dehydration rotation time. It is the result of having recorded the amplitude of each direction of the water tank of (830 [rpm]), and has shown the result of having experimented several times. In addition, the laundry is put in again for each experiment, and the dehydration is performed through the washing process according to the standard course, and the balance state of the laundry at the start of the dehydration is different every time.

  Experiment No. In 1 and 3, the amplitude of the water tank during steady dehydration is relatively small (1.23 [mm] to 3.17 [mm]). At this time, the difference A in the resonance dehydration rotational speed exceeds 20 [rpm]. On the other hand, Experiment No. 2, 4 and 6 have a relatively large water tank amplitude during steady dewatering (2.96 [mm] to 5.92 [mm]), and the difference A in the resonance dewatering speed at this time is 10 [rpm]. When the difference in resonance dehydration speed is large, the vibration level during steady dehydration tends to decrease. Conversely, when the difference is small, the vibration level during steady dehydration tends to increase. Was confirmed.

(Embodiment 2)
FIG. 7 is a graph of a drum rotation control pattern according to the second embodiment of the present invention. First, after the unwinding process, the speed is gradually increased, the unbalanced state is detected in the resonance region, and the vibration waveform pattern in which the vibration in the steady region is predicted to be high (for example, resonance in FIG. 7). If the rotational speed difference is smaller than 10 rpm), the vibration during steady dehydration can be suppressed by reducing the rotational speed during steady dehydration. Further, when the rotational speed at the time of steady dehydration is lowered, the dewatering performance is also lowered. Therefore, the control for maintaining the dewatering performance is performed by increasing the steady dewatering time by a certain time.

  As described above, the drum type washing machine according to the present invention identifies an unbalanced state in which vibration increases during steady dewatering from vibration characteristics in a plurality of directions of the water tank in the resonance region, and based on the result, unbalance determination and dewatering are performed. Since rotation control can be performed, it is useful as a low-vibration low-noise drum type washing machine that can suppress vibration during dehydration.

1 is a block diagram of a washing machine control apparatus according to Embodiment 1 of the present invention. The graph which shows the drum rotation speed of the imbalance detection process in Embodiment 1 of this invention Flowchart showing a series of processes for calculating the resonance dehydration rotational speed difference and correcting the unbalance determination threshold based on the calculation result in the first embodiment of the present invention. The figure which shows the output waveform of the 3-axis acceleration sensor in the spin-drying | dehydration rotation resonance area when 6 kg of laundry is dehydrated. The figure which shows the other output waveform of the triaxial acceleration sensor in the spin-drying | dehydration rotation resonance area when 6 kg of laundry is dehydrated The figure which shows the difference of the resonance dehydration rotation speed when 6 kg of laundry is dehydrated, the acceleration sensor output result at the time of imbalance determination, and the amplitude result of each direction of the water tank at the time of steady dehydration rotation (830 [rpm]) The graph which shows the drum rotation speed of the unbalance detection process in Embodiment 2 of this invention

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Case 11 Drum 12 Motor 13 Water tank 15 Support spring 16 Anti-vibration damper 17 Vibration detection apparatus 20 Unbalance detection means 21 Control means

Claims (7)

A drum provided with water passage holes on the outer periphery, a water tank containing the drum and storing washing water, a motor for rotating the drum, a housing for housing the water tank, a water tank attached between the water tank and the housing An anti-vibration damper that suppresses vibrations of the water, a vibration detection device that detects vibrations in a plurality of directions provided in the water tank, and an unbalance detection means that detects an unbalance amount of the laundry according to the output of the vibration detection device. The unbalance detection means switches the threshold used for the determination of unbalance detection according to the magnitude of the difference in the resonance dehydration rotational speed at which the output peak of each axis obtained from the vibration detection device appears. Drum-type washing machine. The drum type washing machine according to claim 1, wherein a threshold value used for determination of imbalance detection is made smaller as a difference in resonance dehydration rotational speed of each axis is smaller. The drum type washing machine according to claim 1 or 2, wherein unbalance detection is performed after passing through the resonance region. A drum provided with a water passage hole on the outer periphery, a water tank containing the drum and storing wash water, a motor for rotationally driving the drum, a control means for controlling the driving of the motor, and a housing for housing the water tank; An anti-vibration damper that is attached between the water tank and the housing to suppress vibrations of the water tank, a vibration detection device that detects vibrations in a plurality of directions provided in the water tank, and a laundry unloader according to the output of the vibration detection device. An unbalance detection means for detecting a balance amount, and the control means is configured to detect the output peak of each axis obtained from the vibration detection device according to the magnitude of the difference in the resonance dehydration rotational speed. A drum-type washing machine with controlled rotation speed. The drum type washing machine according to claim 4, wherein the smaller the difference in the resonance dehydration rotational speed of each shaft, the lower the rotational speed during steady dewatering. The vibration detection device is an acceleration sensor capable of detecting acceleration in three directions, the first direction is orthogonal to the second direction and the horizontal direction, and the second direction coincides with the rotation axis direction of the drum, The drum type washing machine according to any one of claims 1 to 5, wherein the third direction is orthogonal to the first direction and also orthogonal to the second direction. The drum-type washing machine according to any one of claims 1 to 6, wherein the vibration detection device is provided at a front portion in a rotation axis direction at an upper peripheral portion of the water tank.