JPH0910480A - Centrifugal hydroextractor - Google Patents

Abstract

PURPOSE: To prevent unusual vibration of a drum-type centrifugal hydroextractor when clothes being dehydrated are brought together to one side of the drum. CONSTITUTION: A pocket 60 is formed in one side of a baffle 58, and water is supplied there from an injection nozzle 86 through a water inlet 88. And the load on the drum 54 itself is variable according to the volume of the supplied water. In the process of dehydration, the load imbalance due to the one- sided clothes inside the drum 54 is detected, and the place of the load imbalance will be relocated at a place on the inner surface of the drum 54 opposite to the pocket 60 by 180 deg.. After that, according to the weight of the load imbalance, an allowance range of load imbalance is decided to keep the load balance when clothes are dehydrated. The load imbalance is detected while water is supplied to the pocket 60 from the injection nozzle 86, and when the detected value reaches the allowance range, the water supply is stopped and a high speed dehydration process is started.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention stores laundry in a basket-shaped drum and rotates the drum at a high speed around a horizontal axis to remove water from the laundry or drain the washing solvent. The present invention relates to a centrifugal dehydrator.

[0002]

2. Description of the Related Art A drum-type centrifugal dehydrator has a structure in which washed clothes are accommodated in a basket-shaped drum, and the drum is rotated at a high speed about a horizontal axis. One of the major problems with this type of centrifugal dehydrator is that when the drum is rotated at high speed while the clothes are not evenly distributed on the inner peripheral wall of the drum, abnormal vibration occurs due to imbalance in the mass distribution around the rotation axis. Or abnormal noise.

A centrifugal dehydrator for the purpose of solving such problems has been conventionally proposed. For example, in the centrifugal dehydrator disclosed in Japanese Unexamined Patent Publication No. 6-254294, a method is disclosed in which the clothes inside the drum are evenly distributed by the low speed rotation of the drum before the dehydration operation by the high speed rotation of the drum. More specifically, a two-stage drum rotation control in which the drum is rotated at a low speed for an extremely short time, and then the drum is rotated at a rotation speed slightly higher than the rotation speed but sufficiently lower than the rotation speed during the spin-drying operation. Is combined to disperse the clothes inside the drum.

Further, in this prior art, a vibration monitoring sensor is installed on a pedestal portion of the apparatus as a means for detecting imbalance of clothes in a drum, and the rotational speed of the drum is reduced to a high rotational speed for performing a dehydrating operation. When the vibration monitoring sensor detects abnormal vibration when the sensor is raised, the rotation speed is reduced.

[0005]

However, even if the method of controlling the rotation of the drum as in the above-mentioned prior art is used, the clothes are not always uniformly dispersed by one low-speed rotation of the drum. When the drum is rotated at a high speed after an attempt is made to disperse the clothes by the low speed rotation of the drum and abnormal vibration occurs at that time, it is necessary to perform the low speed rotation of the drum again to redistribute the clothes. In this manner, when the dispersion of clothes by low-speed rotation of the drum and the detection of imbalance by high-speed rotation of the drum are repeated a plurality of times, there is a problem that a long time is required for the dehydration process.

Further, when the drum is rotated so that the clothes are evenly distributed as in the above-mentioned prior art, particularly long clothes are entangled while being positioned at the center of the drum, causing a so-called tearing phenomenon. There are cases. If the dehydration operation is performed in this state, there is a possibility that the laundry may be torn.

The present applicant has proposed a centrifugal dehydrator for solving the above problems in Japanese Patent Application No. 7-113628. In this new centrifugal dehydrator, a weight is added to a part of the inner peripheral wall surface in advance so that the drum itself has an unbalanced load, and the size and position of the unbalanced load including the unbalanced load of the drum itself become predetermined. So that the clothes are rearranged. As will be described later in detail, according to this device, the allowable range of the eccentric load is widened, so that there is a great effect that the relocation can be performed in a short time.

The present invention is a further improvement of the centrifugal dehydrator according to the above-mentioned application, and an object thereof is to perform efficient dehydration or dewatering while surely avoiding occurrence of abnormal vibration during dehydration or dewatering operation. Another object of the present invention is to provide a centrifugal dewatering device capable of preventing the laundry from breaking due to a tearing phenomenon.

[0009]

SUMMARY OF THE INVENTION A centrifugal dehydrator according to the present invention has a basket-shaped drum for accommodating laundry and rotating the drum around a horizontal axis to dehydrate or wash the laundry. In a centrifugal dehydrator that dewaters a cleaning solvent, a) a drum having an unbalanced load by providing a weight variable weight part on a part of its peripheral wall surface, and b) rotationally driving the drum. Motor, c) an unbalanced load detection means for detecting the magnitude and position of the unbalanced load, including the unbalanced load of the drum itself when laundry is stored inside the drum, and d) the drum itself When the position of the eccentric load detected by the eccentric load detection means in the state of not having a load is in the vicinity of the position defined with respect to the weight portion, the weight portion is moved to the weight portion according to the magnitude of the eccentric load. Unbalanced load adjusting means for adding weight When the magnitude of the eccentric load detected by the eccentric load detecting means in a state in which the weight to the weight portion is added becomes within a predetermined allowable range by e) the offset load adjusting means,
Rotation speed control means for controlling the motor so as to rotate the drum at a rotation speed for performing the dehydration or liquid removal operation.

The drum in the centrifugal dehydrator according to the present invention is provided with a weight portion on a part of the inner peripheral wall surface of the drum so that the drum itself has an unbalanced load, and the weight of the weight portion is changed. It is made possible. First, when the laundry is stored in the drum and the dehydration process is started, the drum itself is made to have no unbalanced load. Therefore, first, the unbalanced load detection means detects the unbalanced load due to the uneven distribution of the laundry. If the position of the eccentric load at this time is in the vicinity of the position determined with respect to the weight portion, it is possible to balance the drum during dehydration by adjusting the weight of the weight portion. The eccentric load adjusting means applies an eccentric load to the drum itself by increasing the weight of the weight portion. Then, the unbalanced load detection means detects the unbalanced load of the laundry including the unbalanced load of the drum itself, and when the unbalanced load falls within a predetermined allowable range, the increase in the weight of the weight portion is stopped. This permissible range is determined based on the magnitude of the eccentric load caused only by uneven distribution of the laundry, the weight reduction of the laundry due to dehydration, the magnitude of the eccentric load allowable after the dehydration, and the like. That is, if the magnitude of the unbalanced load before dehydration is within a predetermined allowable range, an allowable range that does not cause abnormal vibration during dehydration is selected.

Further, when the position of the unbalanced load due to the uneven distribution of the laundry is not in the vicinity of the position defined with respect to the weight portion, the weight of the weight portion is adjusted to balance the drum during dewatering. It is not possible. For this reason, it is preferable that the rotation speed control means causes the unbalanced load to be generated in the vicinity of a predetermined position by rotating the drum at a rotation speed sufficiently lower than the rotation speed during the dehydration operation.

As a concrete structure of the weight portion, a pocket capable of holding a liquid such as water therein is formed, and the amount of the liquid injected into the pocket determines the magnitude of the unbalanced load which the drum itself has. It is preferable to have a configuration in which is variable. In particular, since a plurality of baffles are usually provided inside the drum for the purpose of promoting agitation of laundry, if the pockets are provided inside the baffles, the structure of the weight portion can be simplified.

Further, the pocket has a liquid injection hole through which the liquid is retained inside by the centrifugal force when the drum is rotated, and the liquid is discharged from the inside at the rotational speed of the drum where gravity exceeds the centrifugal force. Is more preferable.
According to this, the liquid is completely discharged from the pocket until the dehydration is completed and the rotation of the drum is stopped or when the drum is stopped, and the state in which there is no unbalanced load on the drum itself is returned.

[0014]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a vertical cross-sectional view of a drum type washing machine equipped with a centrifugal dehydrator according to an embodiment of the present invention, FIG. 2 is a block diagram of an electric system of the centrifugal dehydrator in the drum type washing machine according to the present embodiment, and FIG. 6 is a flowchart for explaining the procedure of the dehydration process in the example, FIG. 4 is a diagram showing an example of fluctuations in the motor current, FIG. 5 is a diagram showing an example of the relationship between the magnitude of the eccentric load and the fluctuation amplitude of the motor currents, FIG. FIG. 7 is a diagram for explaining a difference in an unbalanced load allowable range depending on whether or not a weight is added to the drum, and FIG. 7 is a diagram showing an arrangement state of clothes in the drum.

First, the overall construction of the drum type washing machine will be described with reference to FIG. Frame 50 of drum type washing machine body
An outer tub 52 is disposed inside the outer tub 52, and a drum 54 for accommodating clothes is installed inside the outer tub 52 while being supported by a main shaft 64. Water passage holes 56 are formed in the peripheral wall of the drum 54, and the wash water supplied to the outer tub 52 flows into the drum 54 through the water passage holes 56, and
The water dewatered from the clothes inside is discharged to the outer tub 52. Inside the drum 54, baffles 58 for scraping clothes as they rotate are installed at a total of three positions at each rotation angle of 120 ° of the drum 54. The three baffles 5
Inside one of the eight pockets 6 for storing water
0 is provided. The clothes are stored in the drum 54 through the clothes insertion port 62.

The main shaft 64 is a bearing 66 mounted on the outer tank 52.
The main pulley 68 is attached to the front end of the main pulley 68. A motor 22 for rotatably driving the drum 54 is arranged below the outer tub 52, and a motor pulley 72 is attached to the rotation shaft of the motor 22. The rotation of the motor pulley 72 is transmitted to the main pulley 68 through the V belt 70. Water supply port 7 for cleaning water and rinse water
Is supplied to the outer tub 52 from the outside via the water supply valve 7
The amount of water is adjusted by 6. The water after cleaning is discharged through a drain port 78 opened and closed by a drain valve 80. Further, the water supplied from the water supply port 74 is also supplied to the weight injection pump 84 via the weight injection valve 82. The water pressurized by the weight injection pump 84 is injected from the injection nozzle 86 toward the water injection hole 88 leading to the pocket 60. Since the water injection hole 88 is formed in a portion close to the center of the drum 54, when the drum 54 is rotating at a rotation speed such that the centrifugal force acting on the water injected into the pocket 60 exceeds gravity, The water in the pocket 60 does not spill out to the outside from the water injection hole 88, and when the centrifugal force reaches a rotational speed lower than the gravity, the water in the pocket 60 is discharged to the outside from the water injection hole 88 when the pocket 60 is above. It

A drive voltage is applied to the motor 22 from the circuit section 90. The circuit unit 90 is composed of a control unit 10, an inverter control circuit 20 and the like which will be described later. The rotation sensor 24 is composed of a light emitting unit installed outside the outer tub 52 and a light receiving unit installed inside the frame 50 with the main pulley 68 interposed therebetween. One opening is formed in the ring-shaped portion of the main pulley 68 located between the light emitting portion and the light receiving portion of the rotation sensor 24.
It is provided in one place, and it is set to 1 during one rotation of the drum 54.
Only once, the light from the light emitting portion reaches the light receiving portion through this opening. As a result, the rotation sensor 24 outputs a detection signal in synchronization with the rotation of the drum 54, that is, a rotation marker.

Next, the electrical structure and operation centered on the circuit section 90 will be described with reference to FIG. The control unit 10 mainly including a microcomputer includes a central control unit 11,
The rotation speed control unit 12, the unbalanced load detection unit 13, and the unbalanced load determination unit 14 are included. The operation unit 16 is provided in the central control unit 11.
Gives instructions for various operation inputs. In addition, an inverter control circuit 20 for applying a drive voltage to the motor 22, a rotation sensor 24, and a motor current detection circuit 26 are provided.

The operation of the electric system will be described below. An operation program for advancing each process of cleaning and dehydration is stored in advance in the internal memory of the central control unit 11. An operator operates a key from the operation unit 16 to perform a dehydration mode,
For example, when the kind of fiber of the clothes to be dehydrated is selected and the start of the dehydration process is instructed, the central control unit 11 reads the corresponding operation program from the internal memory and executes the operation program to advance the dehydration process.

The rotation speed control unit 12 outputs a rotation speed designation signal including a rotation direction instruction to the inverter control circuit 20 based on the operation program. Inverter control circuit 2
0 is pulse width modulation (PWM) of this rotation speed designation signal
The signal is converted into a signal and the drive voltage corresponding to the PWM signal is output to the motor 2
2 is applied. Therefore, the rotation speed control unit 12 and the inverter control circuit 20 together function as rotation speed control means.

The current flowing through the motor 22 is detected by the motor current detection circuit 26 and input to the unbalanced load detection unit 13. When the drum 54 has an eccentric load, the motor current has a fluctuation component corresponding to the eccentric load. FIG. 4 is an example of the waveform of the motor effective value current when there is an unbalanced load. In the figure, the rotation marker is a marker indicating the cycle of one rotation of the drum 54, and is obtained based on the signal from the rotation sensor 24 as described above. As shown in FIG. 4, when there is an eccentric load, the fluctuation of the motor current is synchronized with the rotation cycle of the drum 54. That is, the positive and negative peaks of the fluctuation of the motor current appear at substantially equal positions with respect to the rotation marker. This positive peak position indicates the rotational position where an unbalanced load exists on the drum 54. Further, the amplitude value of the fluctuation of the motor current is a value corresponding to the magnitude of the unbalanced load. FIG. 5 is an example of the result of measuring the relationship between the eccentric load and the amplitude of the motor current fluctuation, and the magnitude of the eccentric load can be estimated from the amplitude value of the motor current fluctuation using such a correspondence relationship. Note that the fluctuation factor of the motor current is not limited to the eccentric load. Therefore, in order to obtain the fluctuation amplitude due to the eccentric load with high accuracy, only the frequency component in the vicinity of the rotation speed of the drum 54 is extracted from the fluctuation component of the motor current. Etc. are desirable.

The position and magnitude of the unbalanced load detected by the unbalanced load detection unit 13 are input to the unbalanced load determination unit 14.
The eccentric load determination unit 14 determines whether the position of the eccentric load is within a range of a desired position on the inner peripheral wall of the drum 54.
The range of this desired position is in the vicinity of a position 180 ° opposite to the mounting position of the baffle 58 having the pocket 60,
The permissible range is set in consideration of position detection errors, variations in the arrangement of clothes, and the like. In addition, the unbalanced load determination unit 14
Then, it is determined whether or not the magnitude of the unbalanced load is within a predetermined range. As will be described later, the predetermined range is variably set according to the range of the unbalanced load allowed after dehydration and the weight of the water poured into the pocket 60, that is, the size of the unbalanced load of the drum 54 itself. It is within the allowable range.

The determination result of the unbalanced load determination unit 14 is input to the rotation speed control unit 12 and the water injection control unit 15. The rotation speed control unit 12 outputs a rotation speed designation signal so as to switch the rotation speed of the motor 22 according to the determination result of the unbalanced load.
Further, the water injection control unit 15 controls the drive of the weight water injection pump 84, and controls the start and stop of water injection from the injection nozzle 86 to the pocket 60 according to the determination result of the unbalanced load.

Next, the difference in the allowable range of the eccentric load between the case where a drum having an eccentric load is used as in the present invention and the case where a drum having no eccentric load is used as in the conventional case is illustrated. This will be described using 6. In the centrifugal dewatering device according to the present invention, the magnitude of the eccentric load that the drum itself has is variable as will be described later, but here, in order to simplify the description, the drum is biased by a fixed weight. It shall have a load. In addition, the unbalanced load after dehydration is 10
If it is within 0 [g], it is assumed that abnormal vibration does not occur during the dehydration operation and the weight of the clothes after the dehydration operation becomes half of that before the dehydration operation.

[0025] (i) as no weight (no unbalanced load on the drum itself) offset load tolerance Figure 6 when (a), the opposing dewatering weight before m ₁ and, respectively with respect to the central axis of the drum When an unbalanced load is generated due to the imbalance of clothes having m ₂ , the condition for preventing abnormal vibration during the dehydration operation is expressed by the following equation (1). | M ₁ −m ₂ | / 2 ≦ 100 (1) Equation (1) can be transformed into the following equation (2). | M ₁ −m ₂ | ≦ 200 (2) In formula (2), by placing clothes so that the unbalanced load before dehydration is within 200 [g], abnormal vibration during dehydration operation is avoided. It shows what you can do.

(Ii) Unbalanced load allowable range when a weight of M [g] is added As shown in FIG. 6B, the pre-dewatering weights m ₁ and m ₂ are respectively opposed to the center axis of the drum. When an unbalanced load is generated due to the imbalance of clothes and the weight of the weight M, the conditions for preventing abnormal vibration during dehydration operation are as follows.
It is shown by the equations (3) and (4). _{(m 2/2) - [} (m 1/2) + M] ≦ 100 ... (3) [(m 1/2) + M] - (m 2/2) ≦ 100 ... (4) Now, for example, M = 300 With [g], the equations (3) and (4) can be summarized as the following equation (5). 400 ≦ m ₂ −m ₁ ≦ 800 (5) From the formula (5), the allowable range of unbalanced load before dehydration is the following formula (6). 100 ≦ m ₂ − (m ₁ + M) ≦ 500… (6)

(Iii) Difference in allowable range between case (i) and case (ii) As can be seen by comparing equations (2) and (6), by adding a weight, The allowable range of eccentric load when performing relocation operation is doubled. Therefore, it becomes easy to keep the unbalanced load within the allowable range by the rearrangement operation.

(Iv) From the viewpoint of detection accuracy of unbalanced load
Difference between (i) and (ii) In the detection of eccentric load based on the fluctuation of motor current as described above, the detection accuracy decreases when the eccentric load is small. Almost impossible.
For example, in the example shown in FIG. 5, it is impossible to detect in the range where the eccentric load is 200 [g] or less, and in the range where the eccentric load is 200 to 300 [g] (the range shown by the broken line in FIG. 5). The detection accuracy is poor and the reliability is poor. Therefore, it is extremely difficult to rearrange the clothes so as to actually satisfy the expression (2).

On the other hand, assuming that the unbalanced load can be surely detected if the unbalanced load is 300 [g] or more, the condition (7) below can detect the unbalanced load before dehydration. m ₂ − (m ₁ + M) ≧ 300 (7) When M = 300 [g], dehydration that can detect an unbalanced load and does not cause abnormal vibration from Eqs. (6) and (7) The allowable range of unbalanced load is given by the following equation (8). 300 ≦ m ₂ − (m ₁ + M) ≦ 500 (8) That is, by adding a weight, the unbalanced load allowable range before dehydration can be easily detected or more accurately detected. Can be set to.

As described above, by imparting an unbalanced load to the drum itself in advance, the following two effects can be obtained. 1) When the clothes rearrangement operation is performed, the allowable range of unbalanced load is wide, so the probability of falling within the allowable range increases. That is, the rearrangement operation becomes easy. 2) Since the unbalanced load allowable range before dehydration is set to the area where unbalanced load can be reliably detected, it is possible to avoid the occurrence of abnormal vibration during dehydration operation due to detection error.

In the above description, the weight of the weight is set to 300 [g], but by appropriately setting the weight, the allowable range of unbalanced load before dehydration can be changed. Generally, the condition of the unbalanced load allowable range before dehydration when the unbalanced load after dehydration is desired to be P [g] or less is expressed by the following equation (9). M−2P ≦ m ₂ − (m ₁ + M) ≦ M + 2P (9) If the magnitude can be reliably detected when the offset load is Q [g] or more, the offset load can be detected and The allowable range of unbalanced load before dehydration that does not cause abnormal vibration is Q ≧ M
At -2P, the following equation (10) is obtained. Q ≦ m ₂ − (m ₁ + M) ≦ M + 2P (10) When the weight of clothes in the drum is less than (M + Q) [g]
Since the formula (10) cannot be satisfied, (M + Q) [g] is the minimum condition for the weight of clothes to be loaded.

In the centrifugal dehydrator according to the present invention, the water held in the pocket 60 serves as the weight in the above description. The weight of the weight can be changed by changing the amount of water.

The procedure of the dehydration process will be described in detail below with reference to the flowchart of FIG. The unbalanced load allowed after the dehydration operation is within 200 [g].

When the washing process is completed and the dehydration process is started, the clothes inside the drum 54 are in the state shown in FIG. 7 (a). At this time, since no water has been poured into the pocket 60, the drum 54 itself does not have an unbalanced load. First, a low speed dispersion operation is performed so that the clothes are stirred and uniformly dispersed on the inner peripheral wall surface of the drum 54 (step S10). That is, the rotation speed control unit 12 outputs a rotation speed designation signal such that the drum 54 rotates at a low rotation speed N ₁ in a range in which the centrifugal force acting on the clothes is smaller than gravity, and the inverter control circuit 20 outputs the rotation speed designation signal. A corresponding drive voltage is applied to the motor 22. The low speed rotation speed N _{1 at} this time is, for example, about 20 [rpm] when the drum diameter is 700 [mm]. Of course, to facilitate the movement of clothes,
The rotation speed may be changed in the vicinity of N ₁ .

Next, low-speed measurement rotation for measuring an unbalanced load due to uneven distribution of clothes is performed (step S1).
1). That is, the rotation speed control unit 12 outputs a rotation speed designation signal that causes the drum 54 to rotate at a low rotation speed N ₂ at which the centrifugal force acting on the clothes is slightly higher than the rotation speed at which the centrifugal force is balanced with gravity, and the inverter control circuit 20 applies a drive voltage corresponding to this to the motor 22. The low speed rotation speed N ₂ is appropriately determined according to the drum diameter and the like. For example, when the drum diameter is 700 [mm], the low speed rotation speed N ₂ is 50 [r
pm].

The rotation speed of the drum 54 is a low rotation speed N ₂
When it reaches, the magnitude and position of the eccentric load are detected by the eccentric load detection unit 13. That is, the magnitude of the eccentric load is detected based on the amplitude of the fluctuation component of the motor current detected by the motor current detection circuit 26, and the position of the eccentric load is detected based on the peak position. Then, the eccentric load determination unit 14 first determines whether or not the magnitude of the eccentric load is equal to or smaller than a predetermined value (step S12). The predetermined value at this time is the maximum value of the unbalanced load that does not cause abnormal vibration during the dehydration operation. That is, the fact that the magnitude of the unbalanced load is equal to or smaller than the predetermined value in step S12 indicates that the clothes in the drum 54 are dispersed substantially uniformly by the dispersion operation. In this case, the process proceeds from step S12 to S18, and a dehydration operation as described below is executed.

If the unbalanced load is larger than the predetermined value, the process proceeds from step S12 to S13, and the position of the unbalanced load is determined. That is, the position of the eccentric load is the position L _{1 of the} pocket 60.
Therefore, it is determined whether or not it is near the position L ₂ which is 180 ° opposite to the drum central axis (step S13). If the position of the unbalanced load is not near the position L ₂ , step S13
To S14, the low speed rearrangement operation is performed (step S14). For example, the drum 54 is rotated at a rotation speed N _{3 in} which the centrifugal force acting on the clothes in the drum 54 is smaller than the gravity so that the movement of the clothes is promoted.
Rotational speed at this time may be a N _1, N ₁ and N ₂
The rotation speed may be between. Further, if the rotation control is performed while detecting the rotation position of the drum 54 by the rotation sensor 24 so that the position of the unbalanced load becomes a desired position, the clothes can be more reliably rearranged. For example, pocket 60
Within a range of a rotation angle of 180 ° located in the upper half of the drum 54, a swinging operation is performed such that left rotation and right rotation are alternately performed at an extremely low speed, for example, 10 to 20 [rpm]. Is also good. Then, after performing the rearrangement operation, the processes of steps S11 to S13 are repeated.

When the position of the eccentric load is near the position L ₂ , the process proceeds from step S13 to S15, and the water injection control unit 1
The allowable range of the unbalanced load is determined based on the magnitude of the unbalanced load already detected in 5. This allowable range is determined as follows.

That is, the condition of the allowable range of the unbalanced load before dehydration when the unbalanced load after the dehydration operation is set to P [g] or less is shown by the equation (10), so that P = 200 [g] , Q = 200 [g], the equation (10) becomes the following equation (11). 200 ≦ (m ₂ −m ₁ ) −M ≦ M + 400 (11) Here, (m ₂ −m ₁ ) is the detected value of the unbalanced load when there is no unbalanced load on the drum 54 itself, so in step S11 It corresponds to the magnitude of the unbalanced load detected. Therefore, the unbalanced load determination unit 14 determines the range of the unbalanced load magnitude such that the expression (11) can be satisfied (step S15).

For example, clothing 1 kg containing water is stored, and the drum 5 is moved by the rearrangement operation in step S14.
It is assumed that clothes of weights of 0 [g], 800 [g], 100 [g] and 100 [g] are arranged for the positions L ₁ , L ₂ , L ₃ and L 4 of the inner peripheral wall of ₄ respectively. . At this time, (m ₂ −m ₁ ) becomes 800 [g], and if the condition of weight M is calculated from equation (11), 200 ≦ M ≦ 600
Becomes The allowable range of eccentric load that satisfies this is 200 ≦ m ₂ − (m ₁ + M) ≦ 600 (12).

Next, the unbalanced load determination unit 14 determines whether or not the magnitude of the unbalanced load is within the determined allowable range (step S16). In the case of the above numerical example,
Since the unbalanced load is 800 [g] in the state before the water injection is started, that is, in the state where there is no weight, naturally the condition of the expression (12) is not satisfied, and the process proceeds from step S16 to step S17. Is started (step S17). That is, when the water injection control unit 15 receives the determination result from the unbalanced load determination unit 14 that the unbalanced load is outside the predetermined allowable range, the water injection valve 82 for the weight is opened and the water injection pump 84 for the weight is activated. Water is jetted from the jet nozzle 86. At this time, the rotation of the drum 54 is maintained at the low rotation speed N ₂ . Therefore,
Water is jetted from the jet nozzle 86 while the unbalanced load is detected.

When the drum 54 rotates and the baffle 58 having the pocket 60 reaches the upper side, the injection nozzle 86
The water sprayed from the water passes through the water injection hole 88 and the pocket 60.
Water is injected inside. The water injected into the pocket 60 is retained in the pocket 60 while being attached to the inner peripheral wall surface of the drum 54 by centrifugal force. The amount of water in the pocket 60 gradually increases and the weight increases. As a result, the magnitude of the unbalanced load that is detected gradually decreases and falls within the range that satisfies Eq. (12). At this point, the process proceeds from step S16 to S17,
The weight injection valve 82 is closed, and the weight injection pump 8
4 is stopped (step S18).

Then, the step proceeds from S18 to S19, and the medium speed dewatering rotation is executed. That is, the rotation speed control unit 12 receives the determination result from the unbalanced load determination unit 14 that the unbalanced load is within the predetermined allowable range, the rotation speed designation signal that causes the drum 54 to have the medium rotation speed N _4. Is output, and the inverter control circuit 20 applies a drive voltage corresponding thereto to the motor 22. Here, the medium speed N ₄ is, for example, about 500 [rpm]. The drum 54 is rotated at a medium rotation speed N ₄ for a predetermined period of time to perform some dehydration.

After the medium speed dewatering rotation, the step is further S1.
From S9, the process proceeds to S20, and the high-speed dehydration rotation is executed. That is, the rotation speed control unit 12 outputs a rotation speed designation signal such that the rotation speed of the drum 54 becomes the high rotation speed N _5, and the inverter control circuit 20 applies a drive voltage corresponding to this to the motor 22. Here, the high speed rotation speed N ₅ is, for example, about 700 [rpm]. This high speed N ₅ is
The value is preferably set according to the dehydration mode designated by the operator. Complete dehydration is performed by rotating the drum 54 at a high rotation speed N ₅ for a predetermined time.

After the dehydration operation is completed, the drum 54
However, if the centrifugal force acting on the water poured into the pocket 60 becomes smaller than the gravity at this time, the water injection hole 88 is reached when the pocket 60 reaches the upper portion of the drum 54.
The water is drained from the unit, and the original condition with no unbalanced load is restored.

Further, in the present embodiment, the rotational speed N ₂ when the unbalanced load is detected in step S11 and step S1.
If the difference from the rotational speed ₃ when the rearrangement operation of the clothes is performed in 4 is made small, steps S11 to S14 can be repeated in a short time. That is, after performing the rearrangement operation in step S14, the state of the eccentric load is grasped by detecting and determining the eccentric load in steps S11 to S13, and the rearrangement operation of step S14 is performed again as necessary. . By repeating this, the unbalanced load is gradually brought closer to the desired state, and when the position of the unbalanced load reaches a predetermined position, the process proceeds from step S13 to step S15.

Although the above embodiments have been described with respect to the drum type washing machine, it is obvious that the present invention can be applied to a washing machine using a petroleum solvent or the like, that is, a dry cleaner.

[0048]

As described above, according to the centrifugal dehydrator of the present invention, when it is confirmed that abnormal vibration does not occur during dehydration or drainage before dehydration or drainage. Since the dehydration or deliquoring operation is performed only by the high speed rotation of the drum, it is possible to reliably avoid the occurrence of abnormal vibration or abnormal noise during the dehydration or deliquoring operation. In addition, since the drum itself is provided with an unbalanced load and a balance including the unbalanced load is provided, the allowable range of the unbalanced load before dehydration or drainage can be widened. For this reason, it becomes easy to rearrange the laundry in a state in which abnormal vibration does not occur, and efficient dehydration or drainage operation can be performed.

Further, since the dehydration operation is performed in a state where the laundry is unevenly distributed inside the drum, the possibility that the laundry is entangled at the center of the drum is reduced, and the effect of preventing the laundry from tearing can be expected.

By constructing the weight portion as a pocket formed inside so as to be able to hold a liquid, a weight whose weight can be changed from the outside can be easily realized. In particular, if this pocket is formed in the baffle, it is not necessary to newly provide a weight member. Further, in order to prevent an unbalanced load on the drum itself before starting the dehydration or dewatering process, a liquid water injection hole should be provided at a position where the liquid is retained inside by the centrifugal force only when the drum is rotated. Just do it.

[Brief description of the drawings]

FIG. 1 is a vertical sectional view of a drum type washing machine equipped with a centrifugal dehydrator according to an embodiment of the present invention.

FIG. 2 is a block diagram of an electric system of the centrifugal dehydrator according to the embodiment of FIG.

FIG. 3 is a flowchart for explaining a dehydration process procedure.

FIG. 4 is a diagram showing an example of fluctuations in motor current.

FIG. 5 is a diagram showing an example of the relationship between the magnitude of an unbalanced load and the fluctuation amplitude of a motor current.

FIG. 6 is a diagram for explaining a difference in an unbalanced load allowable range depending on whether a weight is added to the drum.

FIG. 7 is a view showing the arrangement of clothes inside the drum.

[Explanation of symbols]

 10 ... Control part 12 ... Rotational speed control part 13 ... Unbalanced load detection part 14 ... Unbalanced load determination part 15 ... Water injection control part 20 ... Inverter control circuit 22 ... Motor 24 ... Rotation sensor 26 ... Motor current detection circuit 54 ... Drum 58 ... Baffle 60 ... Pocket 82 ... Weight injection valve 84 ... Weight injection pump 86 ... Injection nozzle 88 ... Injection hole

Claims (5)

[Claims] 1. A laundry is housed inside a basket-shaped drum,
In a centrifugal dehydrator for dehydrating the laundry or draining a washing solvent by rotating the drum about a horizontal axis, a) by providing a weight variable weight part on a part of the peripheral wall surface thereof. , A drum that itself has an unbalanced load, b) a motor that drives the drum to rotate, and c) the amount of the unbalanced load that the drum itself has when the laundry is stored inside the drum. And a position near the position where the position of the eccentric load detected by the eccentric load detecting device is determined with respect to the weight portion in a state where the drum itself has no eccentric load. And an eccentric load adjusting means for adding weight to the weight portion in accordance with the magnitude of the eccentric load, and e) the eccentric load adjusting means in the state where weight is added to the weight portion. Detected by load detection means When the magnitude of the eccentric load becomes within a predetermined allowable ranges,
Centrifugal dewatering device, comprising: rotation speed control means for controlling the motor to rotate the drum at a rotation speed for performing dehydration or dewatering operation. 2. The rotation speed control means rotates the drum at a rotation speed sufficiently lower than the rotation speed during the dehydration operation when the position of the eccentric load is not near the position defined with respect to the weight portion. The centrifugal dehydrator according to claim 1, wherein an unbalanced load is generated in the vicinity of a predetermined position by causing the above. 3. The weight portion is a pocket formed so as to be able to hold a liquid therein, and the magnitude of the unbalanced load possessed by the drum itself can be varied depending on the amount of the liquid injected into the pocket. The centrifugal dehydrator according to claim 1 or 2. 4. The centrifugal dehydrator according to claim 3, wherein the pocket is provided in a baffle inside the drum. 5. The pocket has a liquid injection hole through which liquid is held inside by a centrifugal force when the drum is rotated, and the liquid is discharged from the inside at a rotational speed of the drum where gravity is greater than the centrifugal force. 5. The method according to claim 4, wherein
Centrifugal dehydrator according to.