JP2007068813A - Drum type washing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a drum type washing machine accurately detecting unbalanced laundry. <P>SOLUTION: A state of laundry in a drum is determined from a difference in rotational frequency which is corrected by an average rotational frequency when the drum 1 is driven for a predetermined conduction angle, so that the state of laundry is accurately determined to prevent vibration or noise from occurring in spin-drying. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a drum-type washing machine that rotates and drives a drum containing laundry to perform washing, rinsing, and dehydration processes.

  2. Description of the Related Art Conventionally, this type of washing machine is configured to drive a drum that stores laundry and is rotatable about a horizontal axis by a motor, and to control the number of rotations of the motor by control means. In such a conventional configuration, the control means obtains the average conduction angle when the drum is controlled for a predetermined time so that the drum has a predetermined rotational speed (for example, 85 r / min) during the dehydration stroke, and the obtained value is 85 r / min. When the drum is driven to rotate at the average conduction angle when the drum is rotated at the average conduction angle, it is determined that the bias of the laundry is large when the rotation speed of the drum is large, and the laundry when the fluctuation width is small Was determined to have a small bias.

  When the bias is large, the rotational speed of the drum is lowered and the clothes are loosened, and then the bias is determined again in the same manner. When there is little bias in the laundry, the drum was rotated at a high speed to perform the dehydration process (see, for example, Patent Document 1).

That is, if the drum is rotated at a high speed with a large amount of laundry in the drum, the drum vibrates greatly due to the unbalance of the laundry and generates noise. The number of rotations of the drum was increased at a high speed with little unevenness.
Japanese Patent Laid-Open No. 10-201985

  However, in the above-described configuration, even if the drum is rotated at an average conduction angle of 85 r / min, the actual drum rotation speed varies from 80 to 86 r / min depending on the amount of laundry, the bias, and the motor characteristics. However, since the fluctuation range of the rotational speed is calculated on the assumption that the average rotational speed is 85 r / min, the actual deviation becomes larger as the difference from 85 r / min becomes larger as the actual rotational speed is 80 r / min. There was a problem that it would be judged larger than.

  SUMMARY OF THE INVENTION The present invention solves the above-described conventional problems, and has an object to accurately determine the bias of the laundry and reduce large vibrations and noises during the dehydration process.

  In order to achieve the above object, a drum-type washing machine according to the present invention includes a drum that accommodates laundry and is rotationally driven around a horizontal or inclined direction as a rotation axis, a motor that drives the drum, and the motor Control means for controlling the rotational speed of the laundry, and the control means determines the state of the laundry in the rotating drum from the fluctuation range of the rotational speed corrected by the average rotational speed when the drum is driven at a predetermined conduction angle. Is to judge.

  As a result, when the conduction angle for controlling the drum to a predetermined rotational speed is applied to the motor and driven, even if the rotational speed of the drum does not reach the predetermined rotational speed due to the amount of laundry, the bias, and the characteristics of the motor, Since the fluctuation range of the rotation speed is corrected by the average rotation speed of the drum, it is possible to accurately detect the state (bias) of the laundry in the drum based on the corrected fluctuation width, and whether or not the dehydration process is advanced. Judgment can be made so that large vibrations and noises are not generated during the dehydration process.

  In the drum type washing machine of the present invention, when the drum is driven at a conduction angle at a predetermined rotational speed, the actual rotational speed of the drum is set to a predetermined rotational speed depending on the amount of laundry, bias, and motor characteristics. Even when different from the above, it is possible to appropriately detect the state (bias) of the laundry in the drum.

  The present invention includes a drum that accommodates laundry and is rotationally driven with a horizontal direction or an inclination direction as a rotation axis, a motor that drives the drum, and a control unit that controls the number of revolutions of the motor. The means is configured to determine the state of the laundry in the rotating drum from the fluctuation range of the rotational speed corrected by the average rotational speed when the drum is driven at a predetermined conduction angle. Even if the drum rotation speed does not reach the specified rotation speed due to the amount, bias, or motor characteristics, the fluctuation range of the rotation speed is corrected by the drum rotation speed, so the state (bias) of the laundry in the drum can be detected accurately. can do.

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

(Embodiment)
FIG. 1 is a longitudinal cross-sectional view showing the main configuration of the drum-type washing machine according to Embodiment 1 of the present invention. The drum 1 is provided with a large number of water passage holes 2 on the entire outer periphery thereof and is rotatably disposed in a water receiving tank 3. One end of a rotation shaft 4 in a substantially inclined direction is fixed to the rotation center of the drum 1, and a drum pulley 5 is fixed to the other end of the rotation shaft 4. The motor 6 is connected to the drum pulley 5 by a belt 7 and rotationally drives the drum 1. A lid 8 is provided at the opening of the drum 1 so as to be freely opened and closed. The water receiving tub 3 is supported by a spring body (not shown) from the washing machine main body 9 to prevent vibration during dehydration from being transmitted to the washing machine main body 9, and a weight for reducing vibration during dehydration (see FIG. Not shown). The heater 10 heats the washing water in the water receiving tub 3.

  The control device 11 controls operations of the motor 6, the heater 10, and the like, and sequentially controls a series of processes such as washing, rinsing, and dehydration.

  Operations in the washing process, the rinsing process, and the dehydrating process of each of the above configurations will be described. When the lid 8 is opened and the laundry is put into the drum 1 and the operation is started, the drum 1 is rotated at a low speed by the motor 6 in the washing process, and the laundry in the drum 1 is lifted and dropped onto the water surface. And washed with the impact force when dropped. Next, the same operation as the washing process is performed in the rinsing process. Next, in the dehydration process, the drum 1 is rotated at a high speed, and the laundry is dehydrated by centrifugal force. At this time, if the laundry in the drum 1 is biased, that is, unbalanced, a large vibration is generated in the drum 1 and the water receiving tub 3, but the vibration isolating damper (not shown) attenuates the vibration. Transmission to the washing machine main body 9 is prevented.

  FIG. 2 is a block diagram showing the configuration of the control device 11 according to Embodiment 1 of the present invention.

  As shown in FIG. 2, the motor 6 is an induction motor and has two poles. When washing is too easy, the drum 1 is rotated at a first rotation speed N1 (for example, 45 r / min), so that 16 poles are used. That is, when the motor 6 is energized through the path a through the power switching means 12, the drum 1 rotates in the forward direction (clockwise from the front of the washing machine body 9). The rotational speed of the motor 6 is detected by the rotational speed detection means 20, and the control means 24 controls the rotational speed of the motor 6 by changing the conduction angle of the voltage applied to the motor 6 by the power switching means 12. The motor 6 is connected to the drum 1 via a motor pulley 13 and a belt 7 and can rotate the drum 1 at a rotational speed of 45 to 100 r / min. Further, by energizing the motor 6 through the path b through the power switching means 12, the drum 1 is rotated in the reverse direction (counterclockwise from the front of the washing machine body 9) at a rotation speed of 45 to 100 r / min. Can be rotated.

  Next, at the time of dehydration, using 16 poles, the drum 1 is increased to a second rotational speed N2 (for example, 100 r / min), and then the number of poles is switched to 2 poles to change the third rotational speed N3. (For example, 900 r / min). That is, by energizing the motor 6 through the path c through the power switching means 12, the motor 6 rotates in the reverse direction (counterclockwise from the front of the washing machine body 9). At this time, the rotation speed of the drum 1 can be controlled between 100 and 900 r / min.

  When washing is too easy, since the rotational torque of the motor 6 is required at a low speed (for example, 45 r / min), the number of motor poles is increased so that the torque is generated at a low speed. min)), the number of motor poles can be reduced and the motor can be rotated at a high speed.

  The control means 24 is constituted by a microcomputer or the like, and controls the heater 10, the water supply valve 14, the drain valve 15 and the like via the power switching means 12 constituted by a bidirectional thyristor or the like, and a series of washing, rinsing and dehydration. The process is controlled sequentially. The heater 10 heats the washing water in the water receiving tank 3, the water supply valve 14 supplies water to the water receiving tank 3, and the drain valve 15 drains the washing water in the water receiving tank 3.

  The input setting means 16 inputs a setting course necessary for the user, the start of the operation, and the like, and outputs the input information to the control means 24. The display means 17 displays the setting contents input by the input setting means 16 and the operation state. The water level detecting means 18 detects the water level in the water receiving tank 3, and the water temperature detecting means 18 detects the water temperature in the water receiving tank 3 and outputs the detection result to the control means 24. The rotation speed detection means 20 detects the rotation speed of the motor 6 to detect the rotation speed of the drum 1 and outputs the detection result to the control means 24. The storage means 21 stores data necessary for a series of controls. In addition, 22 is a commercial power source and 23 is a power switch.

  FIG. 3 is a time chart from the cloth unwinding process to the dewatering process in the embodiment of the present invention. As shown in FIG. 3, the control means 24 drives the drum 1 at the first rotational speed N1 (for example, 45 r / min) before the dehydration stroke for driving the drum 1 at the third rotational speed N3 (for example, 900 r / min). min), a cloth unwinding stroke, a fabric balancing stroke in which the rotational speed is gradually increased from the first rotational speed N1 to the fourth rotational speed N4 (for example, 85 r / min), and then the fourth rotational speed. After performing the unbalance determination process which drives by N4 and detects and determines the bias (unbalance) of the laundry and the motor pole number switching process which switches the number of poles of the motor 6 from 16 poles to 2 poles, the dehydration process I try to enter.

  In the cloth unraveling process, the drum 1 is rotated once to the right and once to the left. The fourth rotation speed N4 is the rotation speed at which the laundry sticks to the inner wall of the drum 1.

  In the above configuration, the operation will be described. After the lid 8 is opened, the laundry is put into the drum 1, the power switch 23 is turned on, and then the start switch (not shown) of the input setting means 16 is operated to operate. When started, the water supply valve 14 operates to supply water. When the water level detection means 18 detects a predetermined water level, the water supply is stopped and the motor 6 is driven. In the washing process, since water is contained in the laundry, the drum 1 is driven to rotate at a low speed by the motor 6 while supplying water, and the laundry in the drum 1 is lifted and falls to the surface of the water. Washed by force.

  At this time, the heater 10 is energized to superheat the washing water in the water receiving tub 3 and the water temperature detecting means 19 detects the water temperature in the water receiving tub 3 to control the temperature of the washing water to a substantially constant temperature. . When the washing process is completed, the drainage pump 15 is operated to discharge the washing water in the water receiving tub 3. Thereafter, in the dehydration process via the rinsing process, the drum 1 is operated at a high speed, and the laundry is dewatered by centrifugation.

  Next, operations from the washing process or the rinsing process to the start of the dehydration process will be described with reference to FIGS. FIG. 4 is a flowchart from the cloth unwinding process to the dewatering process in the embodiment of the present invention. When the washing process or the rinsing process is finished in step 100 and the cloth unraveling process is started, a timer built in the control means 24 is started in step 101, and in step 102, the path a of the power switching means 12 is energized. The motor 6 is turned on. At this time, the rotational speed of the drum 1 is set to the first rotational speed N1 (45 r / min), the rotational speed detection means 20 detects the rotational speed of the motor 6, and the first rotational speed is based on the detection result. The motor 6 is feedback controlled so as to be N1. As shown in FIG. 3, the drum 1 rotates to the right at the first rotation speed N1.

  In step 103, the motor 6 is turned off for about 3 seconds, and in step 104, the motor 6 is turned on by energizing the path b of the power switching means 12 and set to the rotational speed N1 of the drum 1 by the rotational speed detecting means 20. The number of rotations of the motor 6 is detected, and the motor 6 is controlled by this output. Similarly, the drum 1 rotates counterclockwise at the first rotation speed N1. When time t1 has elapsed in step 105, the set rotational speed is gradually increased from N1 to N4 in step 106 (for example, increased by 2 r / min per second). When the time t2 elapses in step 107, the rotational speed of the drum 1 at this time reaches a rotational speed (for example, 85 r / min) to the extent that the laundry in the drum 1 sticks to the inner wall of the drum 1.

  In step 108, the conduction angle of the power switching means 12 when the rotation speed of the drum 1 is controlled to the fourth rotation speed N4 (for example, 85 r / min) is detected, and is fixed to the detected conduction angle. Drive. Actually, since the rotation speed can be detected 10 times during one rotation of the drum 1 when the rotation control is performed at 85 r / min, it is detected as the set rotation speed every time the rotation speed is detected. Since the conduction angle is varied in accordance with the difference in the number of rotations, the average conduction angle in a predetermined time (for example, 5 seconds) is fixed.

  In FIG. 5, in step 109, the control means 24 calculates the fluctuation range of the rotation speed at this time from the rotation signal detected by the rotation speed detection means 20.

  Hereinafter, a method for correcting the fluctuation range will be described.

  Here, FIG. 5 shows the rotation signal of the motor 6 and the rotation signal of the drum 1 as the detection result of the rotation detection means 20 when the conduction angle of the voltage applied to the motor 6 (conduction angle when controlled to 85 r / min) is fixed. The relationship with the rotation speed is shown. Three cycles of the rotation signal are the rotation cycle Tm of the motor 6, and ten cycles of the rotation signal are the rotation cycle Td of the drum 1. Therefore, it is possible to detect the number of rotations of the drum 1 ten times while the drum 1 makes one rotation. That is, at the rotation cycle T1 (ms), the number of rotations of the drum 1 is instantaneously calculated as the number 1. Similarly, since the rotation speeds r2 to r10 are also obtained, the average rotation speed when the drum 1 makes one rotation is expressed by Formula 2. The fluctuation range of the rotational speed is expressed by Equation 3. It can be said that the closer the fluctuation width h of the rotational speed is to 0, the smaller the rotational speed fluctuation in one rotation of the drum 1 is, so that there is less bias (unbalance) of the laundry in the drum 1.

  FIG. 6 is a graph showing the relationship between the average rotational speed of the drum 1 and the fluctuation range in the embodiment of the present invention. In step 110, as shown in FIG. 6, the fluctuation range is corrected from the relationship of the sum of the fluctuation range h of the average rotation speed of the drum 1 and the rotation speed of the laundry drum 4 rotation. In other words, by setting the corrected fluctuation range of the rotational speed to 4, even if the rotational speed obtained by the conduction angle applied to the drum 1 and the actual rotational speed of the drum 1 are different, the bias of the laundry is accurately determined. Can judge well.

  The fluctuation range corrected in step 111 is compared with a predetermined value (for example, 200). If the fluctuation range of the rotational speed is equal to or less than the predetermined value, it is determined that vibration and noise do not increase even if the rotational speed of the drum 1 is increased. After the time t3 has elapsed in step 113, the set rotational speed is gradually increased from N4 (85 r / min) to N2 (100 r / min) in step 114. If the fluctuation range of the rotational speed obtained in step 111 is greater than or equal to a predetermined value, it is determined that vibration and noise increase when the rotational speed of the drum 1 is increased, and the timer is reset in step 112 and the process returns to step 101. In step 115, the drum 1 can be rotated at high speed by switching the number of poles of the motor 6 from 16 poles to 2 poles. When the time t4 has elapsed in step 116, in step 117, the set rotation speed of the drum 1 is increased to N3 (for example, 900 rotations), and the dehydration process is started. When the dehydration process ends, the process proceeds to the next process of step 118.

  In this embodiment, the motor 6 is an induction motor, but may be a commutator motor or the like. In addition, although the number of poles of the motor is two, any number of poles may be used.

  As described above, the drum-type washing machine according to the present invention is controlled so that the laundry has a predetermined rotation speed that sticks to the inner wall of the drum 1, detects the conduction angle at this time, and is driven at this conduction angle. Since the state of the laundry in the drum 1 is determined from the rotation speed and the fluctuation range of the rotation speed, the state of the laundry can be accurately determined, and when the imbalance due to the bias of the laundry is large, By rejecting the transition, it is possible to prevent generation of large vibrations and noises in the dewatering process, which is useful as a drum type washing machine that performs each process of washing, rinsing, and dewatering.

Sectional drawing which shows the principal part structure of the drum type washing machine which concerns on embodiment of this invention. The circuit diagram which shows the structure of the control apparatus of the drum type washing machine Time chart from the cloth unwinding process to the dewatering process of the drum type washing machine Flow chart from cloth unwinding process to dewatering process of the drum type washing machine Relationship diagram between the rotation signal of the motor and the drum rotation of the drum type washing machine Relationship diagram between the average drum rotation speed and fluctuation range of the drum type washing machine

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Drum 6 Motor 12 Power switching means 20 Rotational speed detection means 24 Control means

Claims (1)

A drum which accommodates the laundry and is driven to rotate about a horizontal direction or an inclination direction as a rotation axis; a motor which drives the drum; and a control unit which controls the number of rotations of the motor. A drum type washing machine in which the state of the laundry in the rotating drum is judged from the fluctuation range of the rotational speed corrected by the average rotational speed when the drum is driven at a predetermined conduction angle.