JP2008054960A - Drum type washing machine - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To suppress the entanglement of laundry in a washing process and a rinsing process and retain a rotating speed where the falling position of the laundry becomes the maximum. <P>SOLUTION: A vibration sensor 18 is attached to a water tub 5; and a microcomputer 19 detects the vertical vibration of the water tub 5 to gradually increase the rotating speed, when non-detecting the vibration due to impact of the falling of the laundry at a certain rotating speed, it is determined that the laundry is stuck to the washing tub, and controls a rotating speed lower than the present rotating speed. The microcomputer also detects the vibration by the impact of falling of the laundry, compares its amplitude with the initial state of the washing, and when the amplitude is larger than the initial state, it is determined that the laundry is entangled. When it is determined that the laundry is entangled, the microcomputer shifts the rotation to a disentangling process to dissolve the entanglement of the laundry. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a washing machine that detects vibration of a water receiving tub of a washing machine and controls the number of rotations of a washing tub / dehydration tub during washing or rinsing.

  The drum-type fully automatic washing machine elastically supports a water tub containing a washing tub / dehydration tub whose rotation axis is horizontal or inclined in the washing machine housing, and can be rotated into the water tub by a motor attached to the water tub. The washing tub / dehydration tub provided in the rotator is rotated (see Patent Document 1). In this washing machine, the laundry is stored in a washing tub / dehydration tub (hereinafter referred to as “washing tub”), and after the water is supplied to the washing tub to a predetermined water level, the washing tub is driven.

When the washing tub rotates, the laundry contained in the washing tub is lifted in the rotating direction by the convex baffles and centrifugal forces installed on the inner peripheral surface of the washing tub, and is moved to the washing tub at a certain height. Fall. By this series of steps, the effect of tapping is generated, thereby washing the laundry.
Further, the rinsing process is performed in the same manner as in the case of washing, so that the laundry is rinsed by the force applied by dropping.
JP 2004-350983 A

  As described above, the laundry is lifted by the baffle provided in the laundry tub and the centrifugal force generated by the rotation of the laundry tub. As the washing tub rotates faster and the centrifugal force increases, the laundry is lifted to a higher position. Furthermore, since the centrifugal force becomes larger than gravity when the rotational speed is increased, the laundry is stuck to the washing tub. In such a state, since the laundry does not fall, the effect of tapping is lost and the cleaning power is reduced.

  On the other hand, if the rotational speed is too slow, the centrifugal force is lowered, and the position where the laundry falls is lowered. As a result, the force applied by dropping is reduced, so that the cleaning power is reduced. On the other hand, the rotational speed at which the laundry sticks to the washing tub or the state of falling differs depending on the amount of the laundry. For this reason, it is necessary to determine the rotation speed of the washing tub so as to give a greater drop impact force to the amount of laundry. Thus, the cleaning power can be increased.

  In addition, if the laundry is entangled in the washing step and the rinsing step, the movement of the laundry is limited, so that the force applied to the laundry is reduced, which causes the effect of washing and rinsing to be reduced. In addition, the laundry may be damaged. Furthermore, if the tangled laundry is transferred to the dehydration process as it is, it becomes unbalanced (unevenness of the cloth) and causes vibration and noise.

  In the washing machine described in Patent Document 1 described above, the region where the load torque fluctuation of the motor is maximum is determined as the optimum rotational speed at which the amount of cloth falling in the drum is maximized, and the motor speed is set so as to be the optimal rotational speed. The rotation is controlled. In such motor speed control, since the laundry drop position is not detected, it remains doubtful whether the motor speed actually corresponds to the maximum drop position. Further, since this control method is applied only in the case of specific vector control, it cannot be applied as a general control method.

  Therefore, the present invention prevents the cloth from sticking in the drum and resulting in a state where the washing effect due to dropping is not obtained, and the laundry cloth is entangled with each other so that the imbalance during dehydration does not increase. An object is to provide a drum-type washing machine.

  In order to solve the above problems and achieve the object of the present invention, the drum type washing machine of the present invention includes a water tub, a washing tub, a motor for driving the washing tub, and a rotation speed detection for detecting the rotation speed of the washing tub in the housing. A drum-type washing machine having a vibration sensor for detecting vibrations in a substantially vertical direction of the apparatus and the water tank, wherein at least one of the output of the vibration sensor is a predetermined value at the start of the washing operation process or the start of the rinsing operation process. When the time and the value lower than the threshold value are continuously indicated, the motor is controlled so that the rotational speed is lower than the rotational speed. The vibration sensor of the present invention detects vibrations in a substantially vertical direction of the water tank. This vibration sensor is attached to a part of the water tank or a part of the parts attached to the water tank.

  According to the drum type washing machine of the present invention, the laundry is lifted by the baffle and the centrifugal force, falls from a certain height, and collides with the washing tub. Vibration is generated by the impact of the laundry falling. As the rotational speed increases, the drop position increases, and the vibration amplitude increases. However, when a certain number of rotations is exceeded, the laundry starts to stick to the wall surface of the washing tub. Furthermore, if it sticks completely, impact vibration will disappear.

  When the laundry is completely attached to the wall surface of the washing tub, the vibration of the washing tub becomes a gentle periodic vibration (with the same frequency) synchronized with the rotation due to the cloth bias. Therefore, it can be determined that the laundry is attached at the periodic rotational speed. In this way, the optimum number of rotations of the washing tub in the washing process is found, and thereafter, washing and rinsing are performed at this number of rotations.

  The drum-type washing machine of the present invention includes a water tub, a washing tub, and a motor for driving the washing tub in a housing, a rotation number detecting device that detects the number of rotations of the washing tub, A vibration sensor that detects vibrations in the vertical direction is attached to a part of the water tank or a part of the component attached to the water tank. In a drum-type washing machine equipped with such a vibration sensor, at the start of the washing operation process or at least one of the rinsing operation processes, the magnitude of vibration due to the fall of the laundry output by the vibration sensor at the initial stage of these processes Is recorded for a predetermined time, and a vibration threshold value is calculated. And when the vibration larger than the threshold value calculated by the vibration sensor is detected, the amount of water supplied to the washing tub is increased, and the process proceeds to a loosening step of reversing the rotation direction of the laundry in small increments. Yes.

  The present invention monitors the vibration of the washing tub due to the drop impact of the laundry during the washing and rinsing process by a vibration sensor, compares the sensor output with a predetermined threshold value, and determines whether the cloth is within a certain level. Determine the state of entanglement. When the laundry is not entangled, the individual laundry is lifted and dropped separately, so vibration due to the impact of the drop is small. In contrast, when the laundry is entangled, the entangled laundry becomes a lump and is simultaneously lifted and dropped, so the impact is greater than when it is not entangled. When it is determined that the laundry is tangled in this way, the unwinding operation is entered from the process operation so far, and the rotation of the motor is controlled so as to repeat normal rotation and reverse rotation in small increments.

  According to the present invention, during the washing and rinsing process, the output of the vibration sensor is detected as the drum rotation speed increases, and the optimum rotation speed at which the vibration sensor output is maximized is obtained. Wash and rinse. In this way, by performing washing and rinsing at the optimum rotational speed at which the impact force received by the laundry inside the drum is the strongest, it is possible to improve the cleaning power and the rinsing performance.

  Furthermore, in the washing and rinsing process, the vibration of the washing tub due to the drop impact force of the laundry is monitored by a vibration sensor, the sensor output is compared with a predetermined threshold value, and whether the laundry is within a certain level is determined. Determine if there is entanglement. When it is determined that the laundry is entangled, it is possible to improve the cleaning power and reduce the damage to the laundry by moving to the loosening step. In addition, vibration and noise due to unbalance can be reduced in order to prevent the laundry from moving to the dehydration process while being entangled.

Hereinafter, a drum type washing machine according to an embodiment of the present invention will be described with reference to FIGS.
FIG. 1 shows an external view of the exterior of the washing machine of this embodiment, and FIG. 2 shows a cross-sectional view of the inside of the washing machine. As shown in FIG. 1, the exterior of the washing machine of this example includes an outer frame 1 made of a steel plate, an operation / display panel 2 provided on the upper part of the front surface, and a door 3. A water supply port 4 is provided at the upper rear of the outer frame 1.

  In the washing machine shown in FIG. 2, a water tank 5 for storing cylindrical water is supported by two dampers 6 from two locations at the lower part of the outer frame (only one is shown in FIG. 2). . A cylindrical washing tub / dehydration tub (hereinafter referred to as a washing tub) 7 is rotatably provided in the water tub 5. A large number of dewatering holes 7a are provided on the side surface of the washing tub 7, and a fluid balancer 7b is provided at the upper edge to adjust the eccentricity of rotation by adjusting the amount of water entering the plurality of rooms. This washing tub 7 becomes a so-called rotating drum.

  A plurality of convex baffles 8 are provided on the side surface of the washing tub 7. A support plate 9 is attached to the outside of the bottom surface of the water tank 5, and a motor 10 is fixed to the support plate 9. The drive shaft of the motor 10 penetrates the water tub 5 in a watertight manner (sealed so as not to leak water) and is fastened to the washing tub 7. By this motor 10, the washing tub 7 is rotated forward and reverse in the washing process, the rinsing process and the drying process, and is rotated in one direction in the dehydrating process.

A drain valve 11 for draining washing water is provided on the bottom surface of the water tank 5, and the washing water is discharged out of the washing machine through a drain hose 12 connected to the drain valve 11.
A water supply port 4 is provided at the rear part of the upper surface of the exterior, a water supply valve 13 is provided in the rear housing part, a detergent case 14 is provided at the front part of the top cover, and the water supply port 4, the water supply valve 13 and the detergent case 14 are connected. Configure. Washing water is supplied to the aquarium 5 by this water supply unit.

The amount of water supplied is adjusted by detecting the water level in the aquarium 5 by a water level sensor 15 provided at the upper part of the washing machine. The water level sensor 15 can measure the water level in the water tank 5 by measuring the pressure in the air chamber 16 connected to the water tank 5 at the lower part of the water tank 5 through the tube 17.
A vibration sensor 18 that detects at least a substantially vertical movement of the water tub 5 is disposed at the front (or rear) lower portion of the water tub 5 of such a washing machine. The vibration sensor 18 is, for example, an acceleration sensor using a piezoelectric sensor miniaturized by a MEMS (Micro Electro Mechanical System) technology. The method for detecting the acceleration of the acceleration sensor does not matter. Any acceleration sensor may be used as long as it can detect the acceleration of one axis (x axis), two axes (xy axis), or three axes (xyz axis). In addition, as long as a piezoelectric sensor is used, the acceleration sensor may not be an MEMS sensor.

By detecting the vertical vibration of the water tank 5 using the vibration sensor 18, the motor 10 is controlled as described below in the washing, rinsing and drying steps of the washing machine.
FIG. 3 is a diagram illustrating a control unit that controls the above-described steps of the washing machine of the present example. As shown in FIG. 3, the control unit is configured around a microcomputer (hereinafter referred to as a microcomputer) 19. Based on operation inputs and detection signals from the operation / display panel 2, the water level sensor 15, and the vibration sensor 18, drive units such as the water supply valve 13, the drain valve 11, and the motor 10 are controlled by a control program recorded in advance in the microcomputer 19. Be controlled. The operations of the washing, rinsing and drying processes are controlled by the control of these driving units. The rotational speed of the motor 10 is measured by the rotational speed detection device 20 and sent to the microcomputer 19.

  Next, the number of rotations of the washing machine and the movement of the laundry in the washing process and the rinsing process are schematically shown in FIG. 4 (a) shows a low / medium speed rotation that is a low / medium drop position, FIG. 4 (b) shows an optimum rotation that is a maximum drop position, and FIG. 4 (c) is a high speed rotation that is stuck. First, by controlling the motor 10 by the control unit shown in FIG. 3 described above, the laundry tub 7 containing the laundry 22 is rotated, and when the rotational speed is gradually increased, the laundry becomes the laundry tub 7. Is lifted by the convex baffle 8 arranged inside the, and falls at a certain height (FIG. 4 (a)).

  Here, the direction of the arrow in FIG. 4 indicates the direction in which the laundry falls. The force caused by the drop at this time increases the cleaning power. When the rotation speed of the motor 10 further increases, the height at which the laundry 22 is lifted in the washing tub 7 increases accordingly, and the force applied to the laundry 22 by the fall increases (FIG. 4 (b)). . The height to be lifted is determined by the relationship between the centrifugal force applied to the laundry 22 and the gravity in the washing tub 7. When the rotation speed of the motor 10 is further increased, the centrifugal force applied to the laundry 22 in the washing tub 7 becomes larger than gravity, and the laundry 22 remains stuck inside the washing tub 7 and the laundry 22 falls. Disappears (FIG. 4 (c)).

As described above, when the laundry 22 sticks to the inside of the washing tub 7, a force due to the fall of the laundry 22 is not applied, so that the washing power of the laundry 22 is greatly reduced. Therefore, immediately before the laundry 22 sticks to the washing tub 7, the rotational speed of the motor 10 at which the laundry 22 falls to the highest position in the washing tub 7 has the highest cleaning power (FIG. 4B).
When the laundry 22 is lifted by centrifugal force in the washing tub 7 and falls to the washing tub 7 by gravity, the washing tub 7 rotated by the motor 10 due to the action of the laundry 22 falling in the washing tub 7 and Both the water tanks 5 fixed to the outer peripheral side vibrate.

  FIG. 5 is a diagram showing the rotation speed of the washing tub 7 (same as the rotation speed of the motor 10) and the output of the vibration sensor 18 during the washing process. FIG. 5 (a) shows a state where the laundry is not stuck to the washing tub 7, and FIG. 5 (b) shows a state where the laundry is stuck. When the rotational speed of the motor 10 is increased by the control of the control unit shown in FIG. 3 and the laundry tub 7 vibrates due to the fall of the laundry in the laundry tub 7, as shown in FIG. Peak occurs once or more than once per rotation 32 of the washing tub 7 (the number of peaks depends on the number of baffles).

  Further, when the rotational speed 34 of the motor 10 is increased and the laundry is stuck to the washing tub 7, the laundry does not fall, so that the washing tub 7 does not vibrate. For this reason, only a gentle periodic sensor output 33 due to laundry unbalance (cloth bias) is generated (FIG. 5B). In this state, as shown in FIG. 5 (b), the period of the vibration sensor output 33 is related only to the unbalance of the laundry, and this period coincides with the period of the rotational speed 34 of the motor 10. . On the other hand, the cycle of the sensor output 31 showing the vibration caused by the falling of the laundry shown in FIG. 5A is shorter than the rotation cycle of the washing tub 7 (same as the cycle of the rotation speed 32 of the motor 10).

The vibration generated in relation to the unbalance of the laundry becomes a so-called noise with respect to the vibration caused by the falling of the laundry. Therefore, the sensor output of the vibration sensor 18 is provided in a high-pass filter (not shown) provided in the microcomputer 19. The signal is processed and removed.
As described above, when the laundry is stuck to the washing tub 7, the amplitude of the sensor output 33 indicating the vibration due to the unbalance of the laundry is in the cycle of the rotation number 32 of the motor 10 indicating the rotation of the washing tub 7. It is a vibration with an equal period (vibration due to unbalance) and depends on the amount of unbalance. The amplitude of the sensor output 33 is processed by the high-pass filter and decreases to a certain level. Therefore, by detecting that the output 33 of the vibration sensor is at a certain level, the state where the laundry is stuck to the washing tub 7 is detected. It can be detected accurately. (The sensor output 33 in FIG. 5B is not processed by the high-pass filter. This periodic vibration can be removed by processing with the high-pass filter.)

On the other hand, when the laundry is not attached to the wall surface of the washing tub 7, the sensor output 31 indicating the vibration due to the drop impact of the laundry remains without being removed, and therefore the sensor output indicating the vibration due to the drop impact of the laundry. The amplitude of 31 hardly decreases.
Therefore, the microcomputer 19 compares the signal processed by the high-pass filter with a threshold value having a predetermined amplitude stored in advance, and when the threshold value is exceeded, the laundry is stuck to the wall surface of the washing tub 7. It is determined that the laundry is falling, that is, the laundry is falling.

  In this way, in the drum type washing machine of this example, washing can be performed at a rotation speed of 34 or less determined that the laundry is stuck. it can. Further, by controlling the rotational speed of the motor to an optimal rotational speed (for example, a rotational speed lower by 3 rpm) than the sticking rotational speed 34, the laundry can be dropped from the highest position of the washing tub 7, The washing power can be improved and the washing time can be shortened.

  Since the optimum rotation speed varies depending on the capacity of the laundry, the microcomputer 19 performs control for determining the optimum rotation speed every time the washing process is started. This step is performed in a time that is substantially the same as one forward rotation of the washing step described later, and also in this step, the washing and rinsing effects can be obtained, so that the washing time does not become longer. Although it is sufficient to perform this process once at the start of washing, it may be monitored whether the laundry is stuck in a timely manner while the washing process is being performed at the optimum rotation speed.

  FIG. 6 is a flowchart for explaining the optimum rotational speed determination operation at the beginning of the washing process. Each processing flow of the optimum rotational speed determination operation is executed by a control program in the microcomputer 19. FIG. 7 shows a change in the rotational speed of the washing tub 7 in the optimum rotational speed determination operation. As shown in FIG. 6, in the washing process, first, the microcomputer 19 opens the water supply valve 13 (step S <b> 1) and supplies water into the water tank 5. At this time, the microcomputer 19 receives the detection signal from the water level sensor 15, detects the water level, and detects that the water has been supplied up to the predetermined water level L1 (step S2), then controls and closes the water supply valve 13 (step S3). .

  Next, the microcomputer 19 controls the motor 10 to adjust water and detergent to clothes, and performs normal rotation and reverse rotation for 20 seconds at 40 rpm, and stops the rotation of the motor 10 (step S4). Subsequently, the microcomputer 19 increases the rotational speed of the washing tub 7 by the motor 10 to 40 rpm (step S5). The microcomputer 19 records the current rotation speed of the motor 10 in the recording area Rnew in the RAM built in the microcomputer 19 (step S6). The microcomputer 19 takes the difference while reading the sensor output of the vibration sensor 18. By taking this difference, the sensor output of the low frequency component is removed (high-pass processing is performed), so that the sensor output signal having a high frequency is emphasized (step S7).

  In this state, the microcomputer 19 monitors the sensor output of the vibration sensor 18 for 5 seconds (step S8). And it is judged whether the difference of the sensor output at the time of monitoring of step S8 is below a predetermined threshold value (step S9). If the difference in sensor output at the time of monitoring exceeds the threshold value in the determination step S9, the microcomputer 19 determines that the laundry is not stuck on the washing tub 7, and proceeds to step S10. In step S10, the microcomputer 19 moves the rotational speed of the motor 10 recorded in the recording area Rnew in step S6 to the recording area Rold. Then, the microcomputer 19 increases the rotational speed of the motor 10 by 3 rpm (step S11).

  And it returns to step S6 again. If the difference between the sensor outputs at the time of monitoring is less than or equal to the threshold value in the determination step S9, the microcomputer 19 determines that the laundry is stuck to the washing tub 7, and the motor 10 recorded in the recording area Rold. The rotational speed is recorded in the RAM built in the microcomputer 19 as the optimal rotational speed ωa (step S12). In the subsequent washing process, washing is performed at the optimum number of revolutions ωa corresponding to the number of revolutions indicated by the washing revolution number determination 41 in FIG.

  Next, when the washing tub 7 is rotated by the rotation of the motor 10 in the washing and rinsing process, the laundry may get tangled. If the rotation of the washing tub 7 is continued as it is, the tangled laundry becomes a larger lump, and if left untreated, the laundry will be damaged. In addition, the weight of the laundry is unbalanced when the dehydration process is started, which causes vibration and noise.

  In other words, the laundry is lifted by the centrifugal force generated by the rotation of the washing tub 7, but when the laundry starts to be entangled, the laundry entangled at the time of dropping simultaneously drops, so the vibrations of the washing tub 7 and the water tub 5 increase. The amount of the tangled laundry gradually increases as the laundry tub 7 further rotates. This creates a vicious circle in which vibration caused by falling is further increased.

  FIG. 8 shows the state of the vibration sensor output during the washing or rinsing process. 8A shows a state where the laundry is not entangled, FIG. 8B shows a state where the laundry is entangled, and FIG. 8C shows a state where the laundry is further entangled. When the laundry is not tangled, the laundry falls separately, so the sensor output 51 indicating vibration due to the impact is small (FIG. 8A). However, when the laundry starts to be entangled, the sensor output 53 indicating vibration increases due to the fall of the tangled laundry (FIG. 8B). When the rotation continues further, the amount of the tangled laundry gradually increases, and accordingly, the sensor output 55 indicating vibration due to the fall of the laundry becomes larger (FIG. 8 (c)).

  Next, FIG. 9 shows a flowchart of the operation for determining the threshold value for determining the tangled laundry, and FIG. 10 shows the change in the rotational speed of the washing tub 7 at that time. The flow of each process of determining the threshold value for determining the entanglement of the laundry is executed by a control program in the microcomputer 19. In FIG. 9, the microcomputer 19 reverses the rotation of the motor 10 to change the direction of rotation of the washing tub 7 (step S21), and sets the rotation speed of the motor 10 to the optimum rotation speed ωa (step S22). The optimum rotational speed ωa is the rotational speed at which the washing rotational speed determination 61 shown in FIG. 10 has been performed, similar to that shown in FIGS.

  The microcomputer 19 monitors the sensor output of the vibration sensor 18 for 20 seconds at this rotational speed (step S23). The microcomputer 19 records five in the RAM built in the microcomputer 19 in order from the largest amplitude among the sensor outputs in the monitoring period of 20 seconds in step S23, and obtains the average value V of the five (step S24).

The microcomputer 19 determines an amplitude value that is 1.5 times the average value V obtained in step S24 as a threshold value Vk when determining the tangling of the laundry, and the threshold value Vk is stored in the RAM built in the microcomputer 19. (Step S25). In this way, the determination 62 of the threshold value Vk at the time of the laundry entanglement determination shown in FIG. 10 is performed, and the subsequent tangled monitoring 63 of the laundry is performed based on the determined threshold value Vk.
Thereafter, the microcomputer 19 stops the rotation of the motor 10 (step S26), and when 3 seconds have passed (step S27), the threshold value determination operation for the entanglement determination ends.

  Next, FIG. 11 shows a flowchart of the operation of the washing process. Each processing flow of the washing process is executed by a control program in the microcomputer 19. In FIG. 11, the microcomputer 19 reverses the motor 10 (step S31), and sets the rotational speed of the motor 10 to the optimum rotational speed ωa (step S32). Thus, the cleaning effect is improved by controlling the rotational speed of the motor 10 to the optimal rotational speed ωa. The microcomputer 19 monitors the sensor output of the vibration sensor 18, records five sensor output peaks in order from the maximum in the RAM built in the microcomputer 19, and obtains the average value as V1 (step S33). The microcomputer 19 determines whether the average value V1 is smaller than the threshold value Vk (step S34).

  When the average value V1 is smaller than the threshold value Vk in the determination step S34, the microcomputer 19 determines that the laundry is not involved after 20 seconds have elapsed (step S35). That is, it is determined that the laundry is not entangled when the average value V1 is smaller than the threshold value Vk after 20 seconds. The microcomputer 19 stops the rotation of the motor 10 (step S36) and waits for 3 seconds (step S37).

  Here, the microcomputer 19 determines whether or not the number of times of washing Na has reached a predetermined number of times N1 (step S38). If the number Na of washings is less than the predetermined number N1 in the determination step S38, the process returns to step S31, and the processes and determinations from step S31 to step S38 are repeated again. When the number Na of washings reaches the predetermined number N1 in the determination step S38, the drain valve 11 is opened (step S39), and the washing process is terminated.

  If the average value V1 is larger than the threshold value Vk in the determination step S34, the microcomputer 19 determines that the laundry is involved. The microcomputer 19 determines whether or not the unraveling process is performed three or more times (step S40). If the unraveling process is three or more times in the determination step S40, it is determined that the effect is low even if the unraveling process is performed more than this. Then, using a buzzer or a display panel, the user is warned or displayed on the laundry and prompts the user to rearrange the laundry (step S41). When the loosening process is less than 3 times in the determination step S40, the motor 10 is stopped (step S42) and the process proceeds to the loosening process.

  Next, FIG. 12 shows a flowchart of the operation of the unraveling process, and FIG. 13 shows fluctuations in the rotational speed in the unraveling process. Each processing flow of the operation of the loosening process is executed by a control program in the microcomputer 19. In FIG. 12, in the loosening process, the microcomputer 19 first opens the drain valve 13 (step S51), determines whether or not the predetermined water level L2 is reached (step S52), and supplies water until the predetermined water level L2 is reached in the determination step S52. I do. After supplying water to the predetermined water level L2 in step S52, the microcomputer 19 closes the water supply valve 13 (step S53).

  In this state, the microcomputer 19 reverses the motor 10 (step S54), and rotates the washing tub 7 in the direction opposite to the direction rotated immediately before. The microcomputer 19 increases the rotational speed of the motor 10 (step S55), determines whether or not the rotational speed of the motor 10 has reached 40 rpm (step S56), and in step S56, the rotational speed of the motor 10 reaches 40 rpm. Then, the motor 10 is stopped (step S57). Next, the microcomputer 19 determines whether or not the unwinding process time Th is within 60 seconds (step S58). If the unraveling process time Th is within 60 seconds in determination step S58, the microcomputer 19 performs steps S54 to S57. The operation up to 60 seconds is continued. In FIG. 13, as shown at 71, the loosening process is repeated for 60 seconds.

Then, the microcomputer 19 opens the drain valve 11 (step S59), and determines whether or not the water level has dropped to the original water level L1 (step S60). When the water level drops to the original water level L1 in this determination step S60, the drain valve 11 is closed (step S61). Here, the loosening process shown in FIG. 12 is completed, and the process returns to the washing process shown in FIG. In FIG. 13, as shown at 72, after the loosening process is completed, the process returns to the washing process.
Thereby, the entanglement of the laundry can be suppressed, and it becomes possible to suppress the damage of the laundry, vibration and noise in the dehydration process.
Although the washing process has been described in the above-described embodiment, the same operation is possible in the rinsing process.

It is an external view of the washing machine exterior of the drum type washing machine of this Embodiment. It is sectional drawing inside the washing machine of a drum type washing machine. It is a figure which shows the control part of a drum type washing machine. Fig. 4 (a) is a diagram showing the rotation speed of the washing machine and the movement of the laundry in the washing process and the rinsing process. Fig. 4 (c) shows the optimum rotation for the position, and Fig. 4 (c) shows the high-speed rotation for sticking. The output of the vibration sensor during the washing process is shown, FIG. 5 (a) shows a state where the laundry is not stuck to the washing tub, and FIG. 5 (b) shows a state where the laundry is stuck. It is a flowchart which shows the operation | movement of the optimal rotation speed determination at the beginning of a washing process. It is a figure which shows the rotation speed change of the washing tub in a washing process. FIG. 8 (a) shows the state of the vibration sensor output during the washing or rinsing process, FIG. 8 (a) shows a state where the laundry is not entangled, FIG. 8 (b) shows a state where the laundry is entangled, and FIG. ) Indicates that the laundry is further tangled. It is a flowchart which shows the operation | movement which determines the threshold value of judgment of the entanglement of the laundry. It is a figure which shows the change of the rotation speed of a washing tub at the time of determining the threshold value of the determination of the tangle of laundry. It is a flowchart which shows operation | movement of a washing process. It is a flowchart which shows operation | movement of a loosening process. It is a figure which shows the fluctuation | variation of the rotation speed in a loosening process.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Housing | casing, 2 ... Display and operation panel, 3 ... Cover, 4 ... Water supply port, 5 ... Water tank, 6 ... Damper, 7 ... Washing tub and dehydration layer, 8 ... Baffle, 9 ... Support plate, 10 ... Motor, DESCRIPTION OF SYMBOLS 11 ... Drain valve, 12 ... Drain hose, 13 ... Water supply valve, 14 ... Detergent case, 15 ... Water level sensor, 16 ... Air chamber, 17 ... Tube, 18 ... Vibration sensor, 19 ... Microcomputer, 20 ... Rotation speed detection apparatus

Claims (3)

A drum-type washing machine having a water tub, a washing tub, a motor for driving the washing tub, a rotation speed detecting device for detecting the rotation speed of the washing tub, and a vibration sensor for detecting vibrations in a substantially vertical direction of the water tub in a housing. And
If at least one of the start of the washing operation process or the start of the rinse operation process, the output of the vibration sensor continues to show a value lower than a predetermined threshold value for a predetermined time, the threshold is set. The drum-type washing machine, wherein the motor is controlled so that the number of rotations is lower than the number of rotations corresponding to the value. A drum-type washing machine having a water tub, a washing tub, a motor for driving the washing tub in the housing, and a vibration sensor for detecting vibrations in a substantially vertical direction of the water tub,
At least one of the start of the washing operation process or the start of the rinsing operation process, the magnitude of vibration due to falling of the laundry output by the vibration sensor at the initial stage of the process is recorded for a predetermined time, and the vibration threshold value is recorded. When the vibration sensor detects a vibration larger than the threshold value, the amount of water supplied to the washing tub is increased, and the process proceeds to a loosening process in which the rotation direction of the laundry is reversed in small increments. A drum-type washing machine characterized by that. In the drum type washing machine according to claim 2,
A drum-type washing machine having a sound source or a display unit for notifying that when the vibration sensor output continues to show a value higher than a threshold value for a certain period of time.

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