阅读说明：本技术 洗衣机 (Washing machine ) 是由 堀部泰之 尾形恭代 中尾浩 于 2019-08-07 设计创作，主要内容包括：本公开的洗衣机具有：机壳；外筒,其弹性地支承于所述机壳的内部；内筒,其内置于所述外筒并旋转自如地配置；供水部,其向所述外筒内供水；水位检测部,其对所述外筒内的水位进行检测；排水部,其将所述外筒内的水排出；泡沫检测部,其具有包括第1电极以及第2电极的一对电极；以及控制部,其对包括洗涤、漂洗、脱水中至少一者的洗涤运转进行控制。针对在所述水位到达预定水位为止的期间内,所述一对电极间的电阻低于预定值的情况而言,所述控制部判断为所述一对电极间发生了短路。(The washing machine of the present disclosure has: a housing; an outer cylinder elastically supported inside the housing; an inner cylinder which is disposed inside the outer cylinder and is freely rotatable; a water supply unit for supplying water into the outer cylinder; a water level detection unit that detects a water level in the outer tub; a drain unit that drains water in the outer tube; a bubble detecting section having a pair of electrodes including a 1 st electrode and a 2 nd electrode; and a control unit for controlling a washing operation including at least one of washing, rinsing, and dewatering. The control unit determines that a short circuit has occurred between the pair of electrodes when the resistance between the pair of electrodes is lower than a predetermined value during a period until the water level reaches a predetermined water level.)

1. A washing machine, wherein,

the washing machine has:

a housing;

an outer cylinder elastically supported inside the housing;

an inner cylinder which is disposed inside the outer cylinder and is freely rotatable;

a water supply unit for supplying water into the outer cylinder;

a water level detection unit that detects a water level in the outer tub;

a drain unit that drains water in the outer tube;

a bubble detecting section having a pair of electrodes including a 1 st electrode and a 2 nd electrode; and

a control part for controlling the washing operation including at least one of washing, rinsing and dewatering,

the control unit determines that a short circuit has occurred between the pair of electrodes when the resistance between the pair of electrodes is lower than a predetermined value during a period until the water level reaches a predetermined water level.

2. The washing machine according to claim 1, wherein,

the predetermined water level corresponds to a height at which a lower end of the inner tub is located.

3. The washing machine according to claim 1 or 2,

the 1 st electrode is disposed at a position lower than the predetermined water level.

4. The washing machine according to any one of claims 1 to 3,

the 1 st electrode is arranged at the lower side of the outer cylinder,

the 2 nd electrode is provided on the upper side of the outer cylinder.

5. The washing machine according to any one of claims 1 to 3,

the washing machine further has:

a warm air supply path for circulating warm air for drying the washings; and

a warm air supply port formed on an upper side of a rear surface of the outer tube and configured to introduce the warm air into the outer tube,

the 1 st electrode is arranged at the lower side of the outer cylinder,

the 2 nd electrode is provided in a predetermined region from the warm air blowing port in the warm air blowing path.

6. The washing machine according to any one of claims 1 to 5,

the control unit performs a drainage operation by the drainage unit in such a case: the resistance between the pair of electrodes is not lower than the predetermined value during a period until the water level in the outer tub reaches the predetermined water level, and the resistance between the pair of electrodes is lower than the predetermined value after the predetermined water level is reached.

7. The washing machine according to any one of claims 1 to 6,

the control unit executes a 1 st washing process in a case where the resistance between the pair of electrodes is not lower than the predetermined value until the water level in the outer tub reaches the predetermined water level,

with respect to the control section, it is preferable that,

wherein the water discharge operation by the water discharge unit is not performed when it is determined that the pair of electrodes is short-circuited until the water level in the outer tub reaches the predetermined water level,

but performs a 2 nd washing process in which at least one of a rotation speed and a rotation time of the inner tub is set to be smaller than that of the 1 st washing process in the 2 nd washing process.

8. The washing machine according to any one of claims 1 to 7,

the washing machine further has a display part for informing the state of the washing operation,

when it is determined that the pair of electrodes is short-circuited, the control unit notifies an abnormality on the display unit after the washing operation is completed.

Technical Field

The present disclosure relates to a washing machine that stirs laundry and washing water.

Background

Patent document 1 discloses a washing machine that suppresses the generation of detergent bubbles generated during washing.

The drum-type washing machine disclosed in patent document 1 includes an outer tub, a rotary drum rotatably disposed in the outer tub, a drain for draining washing water from the outer tub, and a bubble detector including a pair of electrodes. The control unit performs the following control: if the foam detecting part detects foam, the washing machine shifts to a weak washing program and does not operate the drainage part within a preset time. The control part returns to the normal washing program if the foam detecting part does not detect foam after the predetermined time, and operates the water discharging part to discharge the water in the outer cylinder if the foam detecting part detects foam.

Documents of the prior art

Patent document

Patent document 1: japanese patent laid-open publication No. 2007-117139

Disclosure of Invention

However, the above-described conventional washing machine has the following problems: in the case where a short circuit occurs in the foam detection unit, it is impossible to determine the generation of detergent foam.

The present disclosure provides a washing machine having a bubble detecting part detecting generation of detergent bubbles generated during washing, and capable of appropriately coping with a short circuit of the bubble detecting part.

The washing machine of the present disclosure has: a housing; an outer cylinder elastically supported inside the housing; an inner cylinder which is disposed inside the outer cylinder and is freely rotatable; a water supply unit for supplying water into the outer cylinder; a water level detection unit that detects a water level in the outer tub; a drain unit that drains water in the outer tube; a bubble detecting section having a pair of electrodes including a 1 st electrode and a 2 nd electrode; and a control unit for controlling a washing operation including at least one of washing, rinsing, and spin-drying. The control unit determines that a short circuit has occurred between the pair of electrodes when the resistance between the pair of electrodes is lower than a predetermined value until the water level reaches a predetermined water level.

The washing machine of the present disclosure has a bubble detecting part detecting generation of detergent bubbles generated during washing, and can appropriately cope with a short circuit of the bubble detecting part.

Drawings

Fig. 1 is a side sectional view of a drum-type washing machine according to embodiment 1.

Fig. 2 is a flowchart showing the operation of the control unit of the drum-type washing machine.

Fig. 3 is a schematic view showing a case where abnormal foaming occurs in the bubble detecting portion of the drum type washing machine or a case where a short circuit due to deposits occurs.

Fig. 4 is a schematic diagram showing the resistance value of the bubble detecting portion and the temporal change of the water level in the water tank of the drum-type washing machine.

Detailed Description

Hereinafter, the embodiments will be described in detail with reference to the accompanying drawings as appropriate.

(embodiment mode 1)

Fig. 1 is a side sectional view of a drum-type washing machine according to embodiment 1 of the present disclosure.

As shown in fig. 1, the water tank 33 is swingably supported in an antivibration manner by an antivibration member 41 or the like disposed on the lower side of the washing machine main body 39. The rotary drum 31 is rotatably provided in the water tank 33, and is disposed such that the rotation center axis thereof is inclined downward from the front side toward the rear side. The rotary drum 31 is formed in a bottomed cylindrical shape, and has a plurality of water passage holes 32 on the entire outer peripheral portion. A plurality of projection plates 36 for stirring laundry are provided on the inner wall surface of the rotary drum 31. An opening 38 is provided on the front side of the water tank 33 and the rotary drum 31, and the opening 38 is openably and closably covered by a lid 37. The user can put laundry into the rotary drum 31 or take laundry out of the rotary drum 31 through the opening 38 by opening the lid 37.

The water supply valve (water supply unit) 44 supplies water into the water tank 33 through a water supply path 45. The control unit 57 is disposed on the lower side of the main body. One end of the drain path 42 is connected to a lower portion of the water tank 33, and the other end of the drain path 42 is connected to a drain valve (drain portion) 43 for draining the washing water in the water tank 33.

A rotary shaft 34 is provided on the back surface of the rotary drum 31. A motor 35 is connected to the rotating shaft 34, and the motor 35 is attached to the back surface of the water tank 33. The motor 35 is a dc brushless motor or the like, and is controlled to rotate in the forward and reverse directions and to have a variable rotation speed by a control unit 57, a drive circuit (not shown), and the like. The load applied to the motor 35, that is, the amount of laundry is detected based on a signal from a current detection circuit (not shown).

The drum-type washing machine includes a heater 47, a blower fan 48, and a warm air blowing path 49 as a structure for realizing a drying function. A warm air intake port (not shown) for taking in air in the water tank 33 is provided on the back of the upper surface of the water tank 33. The warm air blowing port 51 is provided on the upper side of the back surface of the water tank 33. The warm air flows into water tub 33 and rotary drum 31 in the direction of arrow a, and the air inside rotary drum 31 and water tub 33 is heated and circulated, thereby drying the laundry.

Information from an input setting unit 58 for setting an operation process and the like is input to the control unit 57. The control unit 57 causes the display unit 59 to display the set contents based on the inputted information, and notifies the user of the contents. When the start of operation is set by the input setting unit 58, data from the water level detection unit 46 and the like that detect the water level in the water tank 33 is input to the control unit 57, and the control unit 57 controls the operations of the water discharge valve 43, the water supply unit 44, the blower fan 48, the heater 47, and the like via a load driving unit (not shown). The control unit 57 controls the motor 35 via a drive circuit (not shown). The control unit 57 performs an operation of a washing process including at least one of washing, rinsing, dewatering, and drying.

The bubble detecting unit 70 is composed of a pair of an electrode 70a disposed on the lower side of the water tank 33 and an electrode 70b disposed on the upper side of the water tank 33 or disposed on the upper side of a predetermined region from the warm air blowing port 51 in the warm air blowing path 49. Here, the predetermined region is a region where detergent bubbles generated in the water tank 33 can reach the upper electrode 70 b. This is because the generation of detergent bubbles is detected by the detergent bubbles reaching the upper electrode 70 b. The upper electrode 70b is disposed at a higher position than the lower electrode 70 a.

Next, the positions where the lower electrode 70a and the upper electrode 70b are arranged will be described with reference to fig. 1. Water levels h1, h2, and h3 each indicate the level of the washing water in water tub 33 with the lower end of water tub 33 as a reference. The water level h1 is a water level when a conventional washing process described later is performed. The water level h2 is a water level corresponding to the height position of the lower end of the rotary drum 31. The water level h3 is a water level corresponding to the height position of the lower electrode 70 a. As shown in FIG. 1, the height of the water level is h1 > h2 > h 3. For example, the water level h1 is about 100mm higher than the water level h 2.

The lower electrode 70a is disposed at a height corresponding to the water level h3, and the water level h3 is lower than the water level h 2. That is, the lower electrode 70a is disposed below the water tank 33 and at a position lower than the rotary drum 31. This makes it possible to distinguish and identify a short circuit and abnormal foaming in the foam detecting portion 70. The upper electrode 70b is disposed at a position higher than the water level h 1.

In fig. 1, the lower electrode 70a and the upper electrode 70b are disposed on the rear side of the water tank 33, but the present invention is not limited thereto, and the lower electrode 70a and the upper electrode 70b may be disposed on the front side of the water tank 33.

The bubble detector 70 is connected to a resistance value determination circuit (not shown). The resistance between the lower electrode 70a and the upper electrode 70b is detected by comparison with a reference resistance in the resistance value determination circuit. When the resistance value between the lower electrode 70a and the upper electrode 70b is equal to or greater than the threshold value, the control unit 57 determines that no foam is present between the pair of electrodes. When the bubble enters between the pair of electrodes, an electrical path is formed by the bubble between the upper electrode 70b and the lower electrode 70a immersed in the water, and a resistance value lower than a threshold value is detected. The judgment resistance value of the resistance value judgment circuit is set to be smaller than a threshold value (for example, 500 k.OMEGA.) when the foam exists, and to be equal to or larger than the threshold value (for example, 500 k.OMEGA.) when the foam does not exist.

With respect to the drum-type washing machine configured as described above, the operation and action in the case where the bubble is detected by the bubble detecting unit during washing will be described with reference to fig. 2 to 4.

Fig. 2 is a flowchart showing the operation of a control unit of a drum-type washing machine according to embodiment 1 of the present invention, fig. 3 (a) is a diagram showing a case where abnormal foaming occurs in a bubble detection unit of the drum-type washing machine, fig. 3 (b) is a diagram showing a case where a short circuit due to deposits occurs in the bubble detection unit of the drum-type washing machine, and fig. 4 is a diagram showing a time change of a resistance value of the bubble detection unit of the drum-type washing machine and a water level in a water tank.

When the washing process is started, the bubble detecting portion 70 starts detection of the resistance value. Until the water level in the water tank 33 reaches the water level h2 corresponding to the height at which the lower end of the rotary drum 31 is located (S101), the control unit 57 determines that no short circuit has occurred between the pair of electrodes and performs a normal washing routine (S103) when the resistance value detected by the bubble detecting unit 70 is not lower than the threshold value (e.g., 500k Ω) (S102, no). Here, the normal washing process (S103) means, for example, supplying water to the water level h1 and operating the rotary drum 31 at the rotation speed of 45r/min for a stirring time period of 12 seconds and 1 second of stop. Here, the conventional washing procedure is also referred to as the 1 st washing procedure.

As shown by the broken line B in fig. 4, in the normal washing process (S103), it is determined whether or not the resistance value of the bubble detecting portion 70 is smaller than the threshold value after reaching the water level h2 (S104), and in the case where the resistance value is smaller than the threshold value, the control portion 57 determines that abnormal foaming has occurred (S105). The abnormal foaming is generated by the washing water containing the detergent component being agitated by the rotation of the rotary drum 31, and the abnormal foaming is generated by the energization between the pair of electrodes as shown in fig. 3 (a). When determining that abnormal foaming has occurred, the control unit 57 performs a defoaming process such as discharging the water in the water tank 33 by the water discharge unit 43 (S106).

Then, when the normal washing process for the 1 st predetermined time, for example, 15 minutes, is ended (S107), the control section 57 ends the washing process (S108), and shifts to the next process.

On the other hand, as shown by a solid line a in fig. 4, in the case where the resistance value of the bubble detecting portion 70 is smaller than the threshold value before the water level reaches h2 (S102, yes), the control portion 57 can determine that abnormal foaming has not occurred. This is because the washing water containing the detergent component is not agitated by the rotation of the rotary drum 31 until the water level in the water tank 33 reaches h2, and thus no abnormal foaming occurs. Therefore, since it can be determined that a short circuit has occurred between the electrodes when the resistance value is smaller than the threshold value, the control unit 57 determines that a short circuit has occurred (S109) when the resistance value is smaller than the threshold value before the water level reaches h2 (S102, yes).

The short circuit between the electrodes is caused by deposits deposited between the electrodes. The deposits are residues of detergent components (detergent residues), thread ends running out of the detergent, and the like. As shown in fig. 3 (b), when these are accumulated between the electrodes of the bubble detecting unit 70, the washing water forms a thin film with the residue of the detergent component or thread ends as a medium due to surface tension, and short-circuits occur between the electrodes.

After S109, no matter what value the resistance value detected by the bubble detecting portion 70 is, the operation of discharging the water in the water tank 33 by the water discharging portion 43 is not performed until the washing is completed (S108) and the next step is shifted. This is because, as described above, substances other than foam adhere between the pair of electrodes, and therefore the control unit 57 cannot accurately determine whether or not abnormal foaming has occurred in the water tank 33 based on the resistance value between the pair of electrodes. When it is determined that the short circuit has occurred (S109), the bubble detecting portion 70 does not function normally. Therefore, when the water discharge operation is performed based on the determination by the bubble detection unit 70, there is a risk that the abnormal foaming is erroneously detected although the abnormal foaming is not actually generated. If false detection occurs, not only unnecessary drainage is caused, but also the detergent components contained in the washing water in the water tank 33 are discharged together, and thus the washing performance is significantly reduced.

However, since abnormal foaming may occur during the period from S109 to the end of the washing step (S108), the control unit 57 executes the 1 st weak washing process (S110) to suppress abnormal foaming when it is determined that a short circuit occurs (S109). The 1 st weak washing process is a process in which the rotary drum 31 is operated at a rotation speed of 35r/min at a weak agitation time period of, for example, 10 seconds and 5 seconds. The agitation by the 1 st weak washing process is weaker than that by the conventional washing process (S103), and therefore foaming can be suppressed. In addition, the phrase "the agitation is performed weaker than the agitation performed in the conventional washing process" means that at least one of the rotation speed and the rotation time of the rotary drum 31 is smaller than that in the conventional washing process. Here, the 1 st weak washing process is also referred to as a 2 nd washing process.

After that, after continuing the washing step and continuing the washing program for the 2 nd predetermined time (S111), for example, for 15 minutes, the control section 57 ends the washing step (S108) and shifts to the next step.

Thereafter, a series of operations of washing operations such as rinsing, dewatering, and drying are performed in sequence, and when the operation is completed, controller 57 causes display 59 to display information indicating that a short-circuit has been detected, and notifies the user of the information. Thus, the user can recognize that the bubble detecting unit 70 does not function normally, and can operate a process (for example, a tub washing process) of washing the water tub 33 and the rotary drum 31 itself. This removes detergent residue and the like deposited between the pair of electrodes of the suds sensing unit 70, thereby preventing the washing machine from being continuously used in a state where the electrodes are short-circuited.

As described above, the drum type washing machine of the present disclosure includes: a washing machine main body 39; a water tank 33 elastically supported inside the washing machine main body 39; a rotary drum 31 disposed rotatably in the water tank 33; a water supply valve 44 for supplying water into the water tank 33; a water level detector 46 for detecting the water level in the water tank 33; a drain valve 43 that discharges water in the water tank 33; a bubble detecting unit 70 including a pair of electrodes, i.e., a lower electrode 70a and an upper electrode 70 b; and a control unit 57 for controlling a washing operation including at least one of washing, rinsing, and spin-drying. When the electrical resistance between the electrodes 70a and 70b is lower than a predetermined value until the water level of the water supplied into the water tank 33 by the water supply unit 44 reaches a predetermined water level, the control unit 57 determines that a short circuit has occurred between the electrodes 70a and 70 b.

This can prevent unnecessary drainage while suppressing an increase in foam due to abnormal foaming even when a short circuit occurs between the lower electrode 70a and the upper electrode 70 b. Therefore, the drum-type washing machine of the present embodiment can appropriately cope with the short circuit of the bubble detecting portion 70.

The predetermined water level may also correspond to a height at which the lower end of the rotary drum 31 is located.

The lower electrode 70a may be disposed at a position lower than a predetermined water level.

The lower electrode 70a may be provided below the water tank 33, and the upper electrode 70b may be provided above the water tank 33.

The drum-type washing machine may further include a warm air blowing path 49 through which warm air for drying laundry circulates, and a warm air blowing port 51 formed on the upper side of the rear surface of the water tub 33 and configured to introduce warm air into the water tub 33. The lower electrode 70a may be provided below the water tank 33, and the upper electrode 70b may be provided in a predetermined region from the warm air blowing port 51 in the warm air blowing path 49.

In this case, the control unit 57 may perform the water discharge operation by the water discharge valve 43: the resistance between the electrodes 70a, 70b is not lower than a predetermined value until the water level supplied into the water tank 33 by the water supply part 44 reaches a predetermined water level, and the resistance between the electrodes is lower than the predetermined value after the water level reaches the predetermined water level.

Thus, the control unit 57 can determine that abnormal foaming has occurred and can perform the washing process after the washing water that has been abnormally foamed is temporarily discharged. Therefore, the drum type washing machine of the present embodiment can distinguish and recognize the short circuit and the abnormal foaming of the bubble detecting portion 70, and can appropriately cope with the abnormal foaming.

Control unit 57 executes the 1 st washing process in a case where the resistance between the electrodes is not lower than a predetermined value until the water level supplied into water tub 33 by water supply unit 44 reaches a predetermined water level. When it is determined that a short circuit has occurred between the electrodes 70a and 70b during a period until the water level supplied into the water tank 33 by the water supply unit 44 reaches a predetermined water level, the control unit 57 may execute the 2 nd washing process without performing the water discharge operation by the water discharge valve 43, and set at least one of the rotation speed and the rotation time of the rotary drum 31 to be smaller in the 2 nd washing process than in the 1 st washing process.

Thereby, foaming caused by agitation of the rotary drum 31 can be suppressed as compared with the conventional washing process. Therefore, the drum-type washing machine of the present embodiment can appropriately cope with abnormal sudsing even when the suds detection unit is short-circuited.

The washing machine may further include a display unit 59 for notifying a state of the washing operation, and when the control unit 57 determines that the electrodes 70a and 70b are short-circuited, the control unit may notify an abnormality by the display unit 59 after the washing process is completed.

Thus, the user can recognize that the foam detecting unit 70 does not function normally. Therefore, by performing the washing process of the water tank 33 and the rotary drum 31 itself, the deposits accumulated between the electrodes of the bubble detection unit 70 are removed, and the short circuit of the bubble detection unit can be appropriately coped with.

(other embodiments)

As described above, embodiment 1 is explained as an example of the technique disclosed in the present application, but the technique in the present disclosure is not limited thereto.

Therefore, other embodiments are exemplified below.

In embodiment 1, a drum-type washing machine is described as an example of a washing machine. The washing machine is not limited to a drum type washing machine as long as it can wash the cloth. Therefore, the washing machine can be a vertical washing machine or a double-groove washing machine. In embodiment 1, a drum-type washing machine having a drying function is described, but a drum-type washing machine not having a drying function can also exhibit the same effects. In addition, even if the electrodes are short-circuited with aging, the increase of bubbles can be prevented and the washing performance can be prevented from being remarkably lowered. Therefore, the present invention is also useful for a cleaning machine or the like that requires a prevention portion capable of protecting electronic components from the influence of foam or the like.

In embodiment 1, a description has been given of an example of an inner cylinder in which a rotary drum 31 is disposed so that its axial direction is inclined downward from the front side to the back side. Since the inner cylinder is only required to be disposed rotatably while being housed in the outer cylinder, the inner cylinder may be disposed along the horizontal direction.

In embodiment 1, a short-circuit determination is performed based on a variation in resistance value during a period until the water level reaches h2 (S102). However, in the case where the water level in the water tank 33 is equal to or higher than h2 until the operation is started, the above-described short-circuit determination (S102) may not be performed. This is because S101 and S102 cannot be sequentially passed, and therefore the short circuit determination itself lacks accuracy. In this case, since there is a possibility of abnormal foaming, even when the resistance value of the foam detecting portion 70 is smaller than the threshold value, the water can be quickly discharged (defoaming process) (S106).

In embodiment 1, abnormal foaming is dealt with by discharging the water in the water tank 33 after abnormal foaming is determined in S105. The countermeasure against abnormal foaming is not limited to discharging the water in the water tank 33, and may be performed by a washing process. For example, when the 1 st weak washing process is performed and the resistance value detected by the foam detection unit 70 is equal to or greater than the threshold value after a predetermined time (for example, 1 minute) has elapsed, the control unit 57 may determine that no foam is present between the electrodes, that is, that the foam has been removed. Thereafter, the routine washing process is resumed (S103), and if the resistance value detected by the bubble detection unit 70 is still less than the threshold value, the water in the water tank 33 may be drained by the drainage unit 43.

In embodiment 1, the 1 st weak washing process is performed in S110. In S110, the 2 nd weak washing process may be performed to be weaker than the 1 st weak washing process. Here, the 2 nd weak washing process is a process in which the rotary drum 31 is operated at a rotation speed of 30r/min at a weaker agitation time period of 5 seconds rotation and 10 seconds stop, for example. Since the 2 nd weak washing process performs agitation weaker than the 1 st weak washing process, foaming can be further suppressed. When the 2 nd weak washing process is performed, the 2 nd predetermined time (S111) may be longer than the 1 st predetermined time (S107) (for example, 20 minutes) in order to secure the washing power. In addition, the 1 st weak washing process may be performed in S103, and the 2 nd weak washing process may be performed in S110. Here, the 2 nd weak washing process is also referred to as a 3 rd washing process.

In embodiment 1, the judgment value for the abnormal foaming judgment (S105) and the judgment value for the short circuit judgment (S109) in the normal washing process (S103) are both set to the same threshold value (for example, 500k Ω), but the present invention is not limited thereto. The abnormal foaming judgment value may be set to a 1 st threshold (e.g., 500 k.OMEGA.) and the short circuit judgment value may be set to a 2 nd threshold (e.g., 250 k.OMEGA.). By using a resistance value lower than the degree of decrease in the normal resistance value due to foaming of the detergent as a criterion for short-circuit determination, the accuracy of short-circuit determination can be improved.

In embodiment 1, the water level h2 is a water level corresponding to the height of the lower end of the rotary drum 31, but is not limited thereto. The water level h2 may be lower than the water level h1, and may be a water level at which the detergent component-containing washing water is not agitated by the rotation of the rotary drum 31 and bubbles are generated.

In embodiment 1, the configuration is such that: a circulation pump 80 communicating with the drain path 42 is provided, and a circulation path 81 communicating with the circulation pump 80 is communicated with a circulation port 82 at the front lower part of the water tank 33 to circulate the washing water in the washing step as indicated by an arrow b. In embodiment 1, the driving of the circulation pump 80 is not described, but may be performed as described below. When the normal washing routine is performed (S103), the rotation speed and the operation rate of the circulation pump 80 (for example, 3500r/min, 30 seconds of operation — 30 seconds of operation stop) may be increased, and when the short-circuit determination is performed (S109), the rotation speed and the operation rate of the circulation pump 80 (for example, 2500r/min, 20 seconds of operation — 40 seconds of operation stop) may be decreased or the circulation pump 80 may be stopped in order to suppress foaming. This can suppress further abnormal foaming promoted by driving of circulation pump 80.

Further, since the above-described embodiments are intended to exemplify the technology in the present disclosure, various modifications, substitutions, additions, omissions, and the like can be made within the scope of the claims and the equivalents thereof.

The present disclosure can be applied to a washing machine that washes laundry. Specifically, the present disclosure can be applied to a vertical washing machine, a drum washing machine, a dual-tub washing machine, and the like.

Description of the reference numerals

31. A rotary drum (inner cylinder); 33. a water tank (outer cylinder); 43. a drain valve (drain unit); 44. a water supply valve (water supply part); 46. a water level detection unit; 57. a control unit; 59. a display unit; 70. a foam detection section; 70a, the lower electrode (1 st electrode); 70b, the upper electrode (2 nd electrode).