WO2003054277A1

WO2003054277A1 - Washing machine

Info

Publication number: WO2003054277A1
Application number: PCT/JP2002/013271
Authority: WO
Inventors: Takako Tazawa; Satoru Nishiwaki
Original assignee: Kabushiki Kaisha Toshiba
Priority date: 2001-12-21
Filing date: 2002-12-18
Publication date: 2003-07-03
Also published as: CN100523358C; KR20040068276A; KR100621279B1; CN1606643A; EP1477606A1; TWI227759B; JP2003181189A; EP1477606A4; US20050034491A1

Abstract

A washing machine according to the invention performs the washing operation while heating the washing liquid contained in a washing tank (9) by a heating element (17). In order to prevent the washing effect from lowering as the amount of foam produced in the washing tank (9) becomes excessive, the arrangement is such that the rotation mode of the washing tank (9) is changed according to a temperature region to which the temperature of the washing liquid belongs.

Description

Details

Washing machine technology

The present invention relates to a washing machine having a heating means for heating a washing liquid during a washing operation.

Background art

A conventional washing machine includes a water tub, a washing tub rotatably housed in the water tub, and a heating element provided at a bottom portion of the water tub to heat the washing liquid in the washing tub. There is. The washing machine is configured such that the washing operation can be performed while heating the washing liquid by the heating element.

When the washing liquid is heated during the washing operation, the enzymes contained in the detergent are activated. In addition, vegetable oils and animal oils and fats contained in clothing dissolve out. Therefore, the laundry can be efficiently washed.

On the other hand, when the temperature of the washing liquid is high, the detergent easily foams. For this reason, the amount of foam generated in the washing tub becomes excessive, and the washing efficiency is reduced. In particular, in the case of a drum-type washing machine, bubbles may overflow from the laundry entrance.

Therefore, in the washing machine having the above-described configuration, when the washing operation is performed while heating the washing liquid, the rotational driving time of the washing tub / the agitator provided inside the washing tub can be shortened,ゃ By reducing the rotation speed of the stirrer, the amount of generated bubbles was suppressed to a small level.

However, in the above-described method, the mechanical cleaning action given to the laundry is reduced. For this reason, there was a problem that sufficient cleaning performance could not be obtained.

Therefore, an object of the present invention is to provide a washing machine capable of improving washing performance when a washing operation is performed by heating a washing liquid.

Disclosure of the invention The washing machine of the present invention includes: a heating unit that heats the washing liquid contained in the washing tub; a temperature detecting unit that detects the temperature of the washing liquid; a rotation driving unit that rotationally drives the washing tub; Control means for controlling a rotation operation of the washing tub by a rotation driving means, wherein the control means determines whether the temperature of the washing liquid detected by the temperature detection means belongs to any of a plurality of temperature ranges. The rotation mode of the washing tub is configured to be changed.

Further, the washing machine of the present invention is provided with heating means for heating the washing liquid contained in the washing tub, temperature detecting means for detecting the temperature of the washing liquid, and rotatably provided in the washing tub. A stirrer, a rotation driving unit that rotationally drives the stirrer, and a control unit that controls a rotation operation of the stirrer by the rotation driving means, wherein the control unit detects the temperature by the temperature detection unit. The rotation mode of the agitator is configured to be changed according to which of the plurality of temperature ranges the temperature of the washing liquid belongs to. The amount of foam generated in the washing liquid increases. However, when the temperature of the washing liquid exceeds a predetermined value, the internal pressure of the foam increases, and the generated foam is easily broken. According to an experiment by the inventor, the amount of foam in the washing tub increased when the temperature of the washing liquid was in a temperature range suitable for activating the enzyme or in a temperature range in which vegetable oils and animal oils and fats eluted. .

Therefore, by rotating the washing tub / stirring body in the rotation mode suitable for the temperature range to which the temperature of the washing liquid belongs as in the above configuration, it is possible to suppress a decrease in the mechanical force applied to the laundry. The washing liquid can be heated until the temperature reaches a temperature sufficient to activate the enzyme or elute fats and oils while suppressing the amount of foam generated by the rotation of the washing tub and the stirring body. . For this reason, the cleaning performance can be improved.

Also, the washing machine of the present invention includes a heating unit for heating the washing liquid stored in the washing tub, a drain unit for discharging the washing liquid from the washing tub, and detecting an amount of foam generated in the washing tub. A cleaning operation execution unit that performs a cleaning operation by heating the washing liquid to the heating unit, wherein the cleaning operation execution unit includes an excessive amount of foam based on a detection result of the foam detection unit. When it is determined that the heat is generated, The heating operation of the washing liquid is stopped, and the discharging operation of the washing liquid by the drainage unit is executed to execute the washing operation.

According to the above configuration, when the amount of foam generated in the washing tub becomes excessive, the washing operation is performed by discharging the washing liquid, so that the cleaning operation is continued while the amount of generated foam is excessive. There is no. In this case, even if the heating means is exposed above the liquid surface of the washing liquid by discharging the washing liquid, the life of the heating means is not shortened because the heating means is stopped. Absent. BRIEF DESCRIPTION OF THE FIGURES

FIG. 1 shows a first embodiment of the present invention, and is a flow chart showing a washing process in a setting state of a warm water washing mode,

FIG. 2 shows the overall configuration of the drum-type washing machine according to the present embodiment, and is a side view with a part cut away.

Figure 3 is a rear view of the drum type washing machine with the back plate of the outer box removed.

FIG. 4 is a block diagram showing the electrical configuration of the drum type washing machine,

FIG. 5 is a diagram showing a normal rotation mode of the washing tub,

Figure 6 is a diagram showing the rotation mode that suppresses the generation of bubbles in the washing tub,

FIG. 7 is a diagram showing the relationship between the temperature of the washing liquid and the amount of generated foam,

FIG. 8 is a diagram corresponding to FIG. 1 showing a second embodiment of the present invention;

FIG. 9 is a diagram corresponding to FIG. 1 showing a third embodiment of the present invention. BEST MODE FOR CARRYING OUT THE INVENTION

The present invention will be described in more detail with reference to the accompanying drawings. First, FIGS. 1 to 7 show a first embodiment in which the present invention is applied to a drum type washing machine. As shown in FIGS. 2 and 3, the drum-type washing machine according to the present embodiment has an outer box 1, a cylindrical water tank 7 disposed inside the outer box 1, and a rotatable inside the water tank 7. It has a drum 9 arranged.

At the center of the front of the outer box 1, there is a laundry entrance 2 which is opened and closed by a door 3. Have been killed. An operation panel 4 is provided on an upper portion of a front portion of the outer box 1, and an operation circuit unit 5 is provided inside the outer box 1 and at a rear portion of the operation panel 4. The operation panel 4 has a setting switch for performing various settings relating to the washing operation and the like, and a display unit (not shown) for performing various displays relating to the washing operation and the like. Further, a control circuit unit 6 is provided in a lower portion of a front portion in the outer box 1.

The water tank 7 is disposed so that its axial center line extends in the front-rear direction, and is disposed so as to be inclined downward and backward. The water tank 7 is supported by a pair of left and right elastic support devices 8.

The drum 9 functions as a washing tub, a dehydration tub, and a drying tub, and is arranged so that its axial direction substantially coincides with the axial direction of the water tub 7. A large number of small holes 10 functioning as water holes and air holes are provided in substantially the entire body of the drum 9. In addition, a plurality of knobs 11 for lifting up the laundry are provided on the inner peripheral surface of the body of the drum 9.

Openings 12 and 13 are provided on the front of the water tub 7 and the drum 9, respectively, for taking in and out laundry. The opening 12 of the water tub 7 is watertightly connected to the laundry entrance 2 by a tongue 14.

On the rear surface of the water tank 7, a motor .15 as a rotation driving means for driving the drum 9 to rotate is disposed. The motor 15 is composed of an outer rotor type brushless motor, and has a stay 15a and a mouth 15b. A bearing housing (both not shown) having a bearing is fixed substantially at the center of the rear surface of the water tank 7, and the stay 15a is fixed to the outer periphery of the bearing housing. The rotary shaft 15c of the entrance 15b is rotatably supported by the bearing. The front portion of the rotating shaft 15c extends through the rear wall of the water tank 7 into the water tank 7, and the rear surface of the drum 9 is fixed to the front end thereof.

A water reservoir 16 protruding downward is provided on the lower surface of the water tank 7. A heating element 17 is provided inside the water reservoir 16. The heating element 17 is made of, for example, a seed wire, and functions as a heating unit that heats the washing liquid in the water tub 7. A drain port (not shown) is provided at the rear of the water reservoir 16, and a drain hose 19 is connected to the drain port via an electric drain valve 18. The drain valve 18 and the drain hose 19 function as drain means.

On the other hand, a blower 20 is provided at the rear of the upper part of the water tank 7. In addition, a heater 21 is disposed in the upper part of the water tank 7 in front of the blower 20. The blower 20 includes a blower blade 23 provided inside the casing 22, and a motor 51 provided outside the casing 22 to rotate the blower blade 23. Have been. The heater 21 includes a case 24 and a heating element 25 for generating hot air, which is provided inside the case 24. The inlet of the case 24 communicates with the outlet of the casing 22. The outlet of the case 24 is connected to a water tank 7 via a duct 26.

A hollow heat exchanger 27 is provided on the left side of the rear surface of the water tank 7. The heat exchanger 27 is curved along the outer periphery of the rear surface of the water tank 7 so as to avoid heat. An air inlet 28 also serving as a water outlet is provided in a portion of the rear end plate of the water tank 7 corresponding to a lower portion of the heat exchanger 27. The upper part of the heat exchanger 27 is connected to a casing 22 of the blower 20 via a duct 29.

A water injection pipe 30 extends over the upper part of the inside of the heat exchanger 27. A large number of fountain ports 30a are provided on the lower surface of the water injection pipe 30, for example, in a state of being arranged in a horizontal row. The connection part 3 Ob which is one end of the water injection pipe 30 is located outside the heat exchanger 27. The connection part 30b is connected to an electric water supply valve 33 via a Y-shaped pipe joint 31 and a water injection tube 32. The water supply valve 33 is attached to the uppermost part in the outer box 1. The heat exchanger 27 is of a water-cooled type that cools and dehumidifies internal air by exchanging heat with water injected from the water injection pipe 30.

A drying unit includes the heat exchanger 27, the blower 20, the heater 21 and the like.

In addition, an air trap 34 is attached to a substantially middle portion of the rear surface of the heat exchanger 27 in the vertical direction. Of the rear surface of the heat exchanger 27, the air trap 34 A small hole (not shown) is provided in the attachment portion, and the heat exchanger 27 and the air trap 34 communicate with each other through the small hole.

A pressure sensor 36 is provided at a rear portion of an upper portion in the outer box 1. The air trap 34 and the pressure sensor 36 are connected by an air tube 35. The pressure sensor 36 detects the pressure in the air trap 34, and employs a high-sensitivity sensor capable of detecting a minute pressure of about several hundreds CPa). The air trap 34 and the pressure sensor 36 constitute a bubble detector 37 (corresponding to a bubble detector).

The air trap 34 is connected to a branch port 31a of the pipe joint 31 via a water injection tube 40. The inside of the air trap 34 is cleaned by water supplied from the water supply valve 33 to the inside of the air trap 34 via the water injection tubes 32 and 40.

In addition, a water level sensor 38 is disposed on the right part (the left part in FIG. 3) of the pressure sensor 36 in the upper part of the outer box 1. The water level sensor 38 detects the water level in the water tank 7 via an air tube 39 and an air trap (not shown).

In addition, a water injection case 41 is provided in the upper front part of the outer box 1. The water supply case 33 is connected to the water supply valve 33 via a connection hose 42. The outlet of the water injection case 41 is connected to the water tank 7 via a water supply pipe 43 o

Further, a detergent input case 44 is housed in the water injection case 41 so as to be able to be pulled out from the front. By storing the detergent input case 44 in the water injection case 41 with the detergent contained therein, the detergent is supplied into the water tank 7 by the water supplied into the case 44. It has become to be.

Further, a temperature sensor 45 composed of, for example, a thermometer is attached to a lower portion of the rear surface of the water tank 7. The temperature sensor 45 detects the temperature of the washing liquid in the water tub 7, that is, in the drum 9, and functions as a temperature detecting means.

FIG. 4 is a block diagram showing an electric configuration of the drum type washing machine according to the present embodiment. ing. The control device 46 (corresponding to control means) is composed of, for example, a circuit mainly composed of a microcomputer, and stores a control program for controlling the entire washing and drying operation. The control device 46 is provided in the control circuit unit 6. The control device 46 is provided with an operation signal of a switch input unit 47, and output signals of the water level sensor 38, the rotation sensor 48, the temperature sensor 45, and the pressure sensor 36. ing. The switch input unit 47 is provided in the operation circuit unit 5 and outputs an operation signal in response to an operation of various switches on the operation panel 4. The rotation sensor 48 outputs a rotation position signal corresponding to the rotation position of the motor 15.

Further, the control device 46 controls the driving of the motor 15 via an inverter circuit 49. Further, the control device 46 includes a buzzer 50, the water supply valve 33, the heating element 17, a motor 51 of the blower 20, and a heating element of the heater 21 via a drive circuit 52. 25, The drive control of the drain valve 18 is performed.

Next, the operation of the present embodiment will be described with reference to FIG. 1 and FIGS. The control device 46 stores a control program for executing a washing operation (including all processes related to a washing operation such as a washing process, a dehydration process, and a rinsing process), and a control program for executing a drying operation. I have. By operating the operation panel 4, the user can execute only the washing operation, execute only the drying operation, or continuously execute the operation from washing to drying. Further, the washing machine according to the present embodiment is provided with a warm water washing mode for heating water in a water tub during a washing process. FIG. 1 shows a flowchart of the washing process executed by the control device 46 when the execution of the washing / drying operation or the washing operation is instructed in the state where the warm water washing mode is set. As shown in FIG. 1, the controller 46 first determines whether or not the water level in the water tank 7 (drum 9) is the predetermined set water level based on the output signal from the water level sensor 38. Judge (step S 1). The set water level is set according to the amount of laundry in the drum 9. Then, when the control device 46 determines that the water level in the water tank 7 is not the set water level (NO in S1), the control device 46 Power is supplied to open the outlet on the connection hose 42 side (step S2).

Thereby, water is supplied from the water supply valve 33 to the water tank 7 via the connection hose 42 and the water injection case 41. At this time, the detergent in the detergent case 44 is supplied into the water tank 7 together with the water. Hereinafter, the mixed liquid of the water and the detergent contained in the water tank 7 (drum 9) is referred to as a washing liquid. The control device 46 drives the motor 15 to rotate the drum 9 while supplying water into the water tank 7. This allows the washing liquid to permeate the laundry in a well-mixed state.

When the water level in the water tank 7 reaches a predetermined set water level (YES in step 1), the control device 46 closes the outlet of the water supply valve 33 (step S3), and proceeds to step S4. In step S4, control device 46 determines whether or not the temperature of the washing liquid is at the upper limit value (for example, 60 [° C]) based on the output signal of temperature sensor 45. If the temperature of the washing liquid is not at the upper limit (NO), the control device 46 causes the heating element 17 • to generate heat (step S5). -Subsequently, the control device 46 determines whether or not bubbles are excessively generated in the drum 9 based on the output signal of the pressure sensor 36 (step S6). If it is determined that the foam is not excessively generated (NO), it is determined whether the temperature of the washing liquid belongs to a temperature range of, for example, 35 to 55 ° C based on the output signal of the temperature sensor 45. Judge (Step S7) o

If it is determined that the temperature of the washing liquid does not belong to the temperature range of 0.35 to 55 ° C (NO), the controller 46 sets the drum 9 in the normal rotation mode (hereinafter, rotation mode).

The cleaning operation is performed by rotating in step A) (step S8). In the rotation mode A, as shown in FIG. 5, the drum 9 rotates at 50 (rpm) in the forward direction (15 seconds), stops (5 seconds), and rotates at 50 (rpm) in the reverse direction. The drive of the motor 15 is controlled so that the state of rotation (15 seconds) and stop (5 seconds) are repeated in order.

On the other hand, when it is determined that the temperature of the washing liquid belongs to a temperature range of 35 ° C to 55 ° C (Y

In ES), the control device 46 drives the drum 9 to rotate in a rotation mode (hereinafter, rotation mode B) for suppressing generation of bubbles to execute a cleaning operation (step S9). In the rotation mode B, as shown in FIG. 6, the drum 9 rotates at 30 (rpm) in the normal rotation direction (2 The drive of the motor 15 is controlled so that the state of (second), stop (5 seconds), rotation at 30 (rpm) in the reverse direction (2 seconds), and stop (5 seconds) are repeated in order. That is, in the rotation mode B for suppressing the generation of bubbles, the rotation speed of the drum 9 is lower and the rotation time is shorter than in the normal rotation mode A.

The washing operation in step S8 or S9 is performed until the temperature of the washing liquid reaches the upper limit. That is, when the temperature of the washing liquid belongs to a temperature range of 35 ° C. or less (corresponding to the first temperature range), the drum 9 is driven to rotate in the rotation mode A, and the temperature range of 35 to 55 ° C. (Equivalent to the second temperature range)), the drum 9 is rotated in the rotation mode B, and if it belongs to the temperature range exceeding 55 ° C (corresponding to the third temperature range), the rotation mode A The drum 9 is driven to rotate.

If it is determined in step S6 that the amount of foam generated in the drum 9 is excessive (YES), the control device 46 stops energizing the heating element 17 and rotates the drum 9 Is stopped to stop the cleaning operation, and the buzzer 50 is operated to notify that an abnormality has occurred (step S10).

On the other hand, if it is determined that the temperature of the washing liquid has reached the upper limit (Y in step S4)

In E S), the flow shifts to step S 11 to stop energizing the heating element 17. Then, in step S12, it is determined whether or not, for example, 10 minutes have elapsed since the temperature of the washing liquid reached the upper limit. If not (NO), the normal rotation The cleaning operation is executed by rotating the drum 9 in the mode A (step S13). This cleaning operation is performed to enhance the cleaning effect. If it is determined in step S12 that 10 minutes have elapsed (Y E S), the washing process ends.

Although the detailed description is omitted, in the remaining stroke of the washing operation, that is, in the spill stroke, after the water is drained from the water tub 7, the water is supplied into the water tub 7 and the drum 9 is rotated. In the dewatering process, the drum 9 is rotated at high speed while draining water from the water tank 7. In the drying operation, after the water is drained from the water tank 7, the drum 9 is alternately rotated in the forward and reverse directions at a low speed, and the blower 20 and the heater 21 are driven. Water is supplied from the water supply valve 33 to the heat exchanger 27 via the water injection tube 32 and the pipe joint 31. As a result, the air in the drum 9 is separated from the heat exchanger 27, the duct 29, the casing 22, and the case 24, It passes through the inside of the object 26 in order and is returned to the drum 9. As a result, the air in the drum 9 is warmed and dehumidified, and the laundry is dried.

Here, FIG. 7 shows the results of an experiment conducted by the inventor on the relationship between the amount of foam generated in the drum 9 and the temperature of the washing liquid. In FIG. 7, the curve LA indicates the case where the drum 9 is rotated in the rotation mode A, and the curve LB indicates the case where the drum 9 is rotated in the rotation mode B. FIG.

As shown in Fig. 7, in all rotation modes, until the temperature of the washing liquid reaches about 40 to 45 ° C, the amount of foam generated increases as the temperature rises, and about 40 to 45 When the temperature exceeds ° C, the amount of foam generated decreases as the temperature increases. This is because, as described above, when the temperature of the washing liquid exceeds a predetermined value, the generated foam is easily broken.

In particular, in the case of the normal rotation mode A, the amount of foam exceeds the allowable limit (indicated by L in Fig. 7) when the temperature of the washing liquid belongs to a temperature range of 35 to 55 ° C.

On the other hand, the temperature at which the enzymes contained in the detergent are activated is 35 ^ 45 ° C. The temperature at which vegetable fats and oils, which are one of the stains on the laundry, dissolve is 40 to 0.45 ° C, and the temperature at which animal fats and oils dissolve is 55 to 65 ° C. Therefore, by performing the washing operation by heating until the temperature of the washing liquid reaches 55 to 65 ° C, various stains on the laundry can be efficiently removed.

Therefore, in this embodiment, the washing liquid is heated until the temperature of the washing liquid reaches the upper limit (60 ° C.), and the temperature range up to the upper limit is divided into three temperature ranges, specifically, 35 ° C. Temperature range below 35 ° C, a second temperature range of 35 to 55 ° C, and a third temperature range of 55 to 60 ° C. The rotation mode was changed depending on whether they belonged.

That is, in the present embodiment, when the temperature of the washing liquid belongs to the second temperature range in which bubbles easily occur, the drum 9 is rotated in the rotation mode B for suppressing the occurrence of bubbles. Further, when the temperature of the washing liquid belongs to the first and third temperature ranges where the amount of generated foam is relatively small, the drum 9 is driven to rotate in the normal rotation mode A. As a result, the washing liquid can be heated until it reaches a temperature sufficient to activate enzymes and elute fats and oils, while suppressing the amount of foam generated in the drum 9 from becoming excessive. , A decrease in the mechanical cleaning action exerted on the laundry can be kept small.

Further, in the present embodiment, when the amount of foam generated in the drum 9 becomes excessive, the cleaning operation is stopped and the buzzer 50 sounds. Thereby, it is possible to reliably prevent the foam generated in the drum 9 from overflowing outside the machine. In addition, the user can quickly find out that an abnormality has occurred in the washing machine.

FIG. 8 shows a second embodiment of the present invention, and different points from the first embodiment will be described. The same parts as those in the first embodiment are denoted by the same reference numerals. FIG. 8 shows a flowchart of a hot water washing operation performed in the washing machine according to the second embodiment. As shown in FIG. 8, in the second embodiment, after the temperature of the washing liquid has reached the upper limit value and the heating of the heating element 17 has been stopped (YES in step S4, step SI1), the drum It is determined whether or not the amount of foam generated in 9 is excessive (step S101).

'If it is determined in step S101 that the bubbles are excessively generated (YES), the process proceeds to step S102, where the drain valve 18 is opened and the inside of the drum 9 ( After discharging a predetermined amount (for example, 2 liters) of the washing liquid in the water tank 7.), the process proceeds to step S12. '

In step S12, it is determined whether or not 10 minutes have elapsed since the temperature of the washing liquid reached the upper limit, and if not, the washing operation is performed in the normal rotation mode A. (Step S13). Thereafter, the process returns to step S101, and the processes from steps S101 to S13 are repeated until "YES" is determined in step S12.

As described above, in the present embodiment, the washing liquid in the water tub 7 is drained when excessive bubbles are generated during the cleaning operation performed to enhance the cleaning effect. As a result, the height position of the foam in the drum 9 can be lowered, and the amount of foam generated by the cleaning operation can be reduced. Further, even if the washing liquid is discharged, the washing effect is not reduced because the washing liquid necessary for the washing operation is contained in the laundry.

By the way, when the washing liquid is discharged, the heating element 17 is above the level of the washing liquid. May be exposed to The heating element 17 is for heating the washing liquid, and when the heating element 17 is energized in a state where the heating element 17 is exposed above the liquid level of the washing liquid, the heating element 17 generates heat to extend its life. descend. However, in the present embodiment, the washing liquid is discharged after the power supply to the heating element 17 is stopped. For this reason, there is no problem even if the heating element 17 is exposed on the surface of the washing liquid.

FIG. 9 shows a third embodiment of the present invention, and different points from the second embodiment will be described. The same parts as those of the second embodiment are denoted by the same reference numerals. That is, the third embodiment is characterized in that the time required for the washing process is set by the user.

Specifically, the user operates the operation panel 4 to set the washing time T. In this case, the washing time is set to, for example, 30 minutes, 60 minutes, 120 minutes, etc. in consideration of the time required for heating the washing liquid by the heating element 17. Choose from the washing times. When the washing time T is set by the user, the controller 46 memorizes the washing time T (Step 7 ° S. 201).

After performing the operation of supplying water into the water tank 7 (steps Tl to 3), the control device 46 starts counting the set time （(step S202). Then, it is determined whether or not the counted time has reached time (Τ10) (step S203), and from step S4 to step S4 until time (Τ — 10) is reached. Execute the processing up to 9. At this time, if it is determined in step S6 that the amount of foam generated in the drum 9 is excessive (Y E S), the process proceeds to step S11. ,

If it is determined in step S203 that the time (T−10) has been reached (ΥES), the process proceeds to step S11.

After the process proceeds to step SI1 and the energization of the heating element 17 is stopped, the processes from steps S101 to S13 are executed. At this time, in the present embodiment, the process of step S204 is executed instead of step S12 of the second embodiment. In step S204, it is determined whether the set time Τ has elapsed. Therefore, the processing from steps S101 to S13 is continued until the set time Τ elapses, and the washing process is ended when the set time Τ elapses. According to such a configuration, even when excessive bubbles are generated during the cleaning operation, the cleaning process is not interrupted. Therefore, the cleaning operation can always be performed only for the cleaning time T set by the user.

The present invention is not limited to the embodiment described above and shown in the drawings. For example, the following modifications are possible.

The present invention is also applicable to a vertical-axis type washing machine including a washing tub having a rotation center axis extending in a substantially vertical direction, and a stirring body rotatably provided at the bottom of the washing tub. In this case, the control means may be configured to change the rotation mode of the stirring body according to the temperature of the washing liquid.

The control device 46 may change only one of the rotation speed and the rotation time of the drum 9 in accordance with the temperature range to which the temperature of the washing liquid belongs.

The boundary temperature between the first temperature region and the second temperature region is not limited to 35 ° C, but may be in the range of 35 to 45 ° C. Further, the boundary temperature between the second temperature region and the third temperature region is not limited to 55 ° C, but may be in the range of 0.5 & 65 ° C. Industrial applicability

INDUSTRIAL APPLICABILITY As described above, the present invention is useful for a washing machine that performs a washing operation by heating a washing liquid.

Claims

The scope of the claims

1. A washing tub containing the washing liquid,

Heating means for heating the washing liquid,

Temperature detection means for detecting the temperature of the washing liquid,

Rotation driving means for rotating the washing tub,

Control means for controlling a rotation operation of the washing tub by the rotation drive means, wherein the control means determines whether the temperature of the washing liquid detected by the temperature detection means belongs to any of a plurality of temperature ranges. A washing machine, wherein a rotation mode of the washing tub is changed.

2. A washing tub containing the washing liquid,

Heating means for heating the washing liquid,

A stirrer rotatably provided in the washing tub,

Rotation driving means for rotationally driving the stirring body,

Control means for controlling a rotation operation of the stirring body by the rotation drive means, wherein the control means determines whether the temperature of the washing liquid detected by the temperature detection means belongs to any of a plurality of temperature ranges. And changing a rotation mode of the stirring body. ,.

3. In the washing machine of claim 1,

The temperature region includes a first temperature region, and a second temperature region that is higher than the first temperature region,

When the temperature of the washing liquid detected by the temperature detecting unit belongs to a second temperature region, the control unit makes the rotation time of the washing tub shorter than when the washing liquid belongs to the first temperature region. And / or reducing the rotation speed of the washing tub.

4. In the washing machine of claim 2,

The temperature region includes a first temperature region, and a second temperature region that is higher than the first temperature region, When the temperature of the washing liquid detected by the temperature detecting unit belongs to a second temperature range, the control unit makes the rotation time of the stirring body shorter than when the washing liquid belongs to the first temperature range. , And Z or reduce the rotation speed of the stirrer.

5. In the washing machine of claim 3,

A boundary temperature between the first temperature region and the second temperature region is set to be not less than 35 and not more than 45.

6. In the washing machine of claim 4,

A boundary temperature between the first temperature region and the second temperature region is set to 35 ° C. or more and 45 ° C. or less.

7. In the washing machine of claim 1,

The temperature region includes a first temperature region, a second temperature region higher than the first temperature region, and a third temperature region higher than the second temperature region. And

The control means, when the temperature of the washing liquid detected by the temperature detection means belongs to the second temperature range, makes the rotation time of the washing tub shorter than when it belongs to another temperature range, And / or reduce the rotation speed of the washing tub.

8. In the washing machine of claim 2,

The control means, when the temperature of the washing liquid detected by the temperature detection means belongs to the second temperature range, makes the rotation time of the stirring body shorter than when it belongs to another temperature range, And / or reduce the rotation speed of the stirring body.

9. In the washing machine of claim 7,

A boundary temperature between the second temperature region and the third temperature region is set to 55 ° C. or more and 65 ° C. or less.

10. In the washing machine of claim 8,

The boundary temperature between the second temperature region and the third temperature region is 55 ° C. or higher and 65 ° C. It is set as follows.

1 1. A washing tub containing the washing liquid,

Heating means for heating the washing liquid,

Drainage means for discharging the washing liquid from the washing tub,

Foam detection means for detecting the amount of foam generated in the washing tub,

Washing operation executing means for executing the washing operation by heating the washing liquid to the heating means,

The washing operation executing means, when judging that foam is excessively generated based on the detection result of the foam detecting means, stops the heating operation of the washing liquid by the heating means, and stops the washing operation by the drain means. The washing operation is performed by executing the washing liquid discharging operation.