Washing machine

Abstract

To provide a drum washing machine capable of excellently washing laundry to which dirt and the like is attached.SOLUTION: A drum washing machine 1 comprises: an outer tank 20 that is disposed in an enclosure 10 and stores water; a drum 23 that is disposed in the outer tank 20 so as to be rotatable around a horizontal axis and stores laundry; a heater 60 to heat the water stored in the outer tank 20; and a control part to execute a washing operation capable of washing laundry to which dirt is attached. The control part executes a hot water bleaching washing step to wash the laundry in the drum 23 with the water containing bleach and heated by the heater 60 by rotating the drum 23 in the washing operation, and executes a tank cleaning step to clean an inner wall surface of the outer tank 20 by rotating the drum 23 at rotation speed higher than the hot water bleaching washing step in the outer tank 20 in which water is stored after the hot water bleaching washing step.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a drum-type washing machine. Such a drum-type washing machine may be one that performs washing and drying continuously, or one that performs washing but does not perform drying. [Background technology]

[0002] Laundry such as baby cloth diapers and underwear that have soiled them with feces (excrement) is often washed by hand using detergent and bleach, which can be a burden for housewives. Furthermore, even with detergent and bleach, room-temperature water tends to be insufficient in removing the dirt and breaking down the pigments in the soiling. The same can be said not only for laundry with soiled soiling, but also for laundry with vomit on it.

[0003] The following Patent Document 1 describes a drum-type washing machine capable of operating a sterilization course that sterilizes laundry using bleach. When the sterilization course is set in this drum-type washing machine, wash water containing detergent and bleach is stored in the tub during the washing process, and laundry is washed with the wash water. Furthermore, if the tub is equipped with a heater, the wash water is heated by the heater before the bleach is supplied to the tub. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Japanese Patent Application Laid-Open No. 2017-143891 Summary of the Invention [Problem to be solved by the invention]

[0005] It is conceivable that laundry contaminated with dirt or vomit may be washed by operating the sterilization course of the drum-type washing machine.

[0006] However, in this case, there is a concern that during the washing process, dirt that falls off the laundry will adhere to the inner wall surface of the water tub (outer tub), particularly the upper inner wall surface that is not submerged, and that users may become anxious that the dirt will adhere to the laundry after the operation has progressed or remain on the inner wall surface after the operation has finished.

[0007] The present invention has been made in view of the above-mentioned problems, and has as its object to provide a drum-type washing machine that can satisfactorily wash laundry having soiling thereon. [Means for solving the problem]

[0008] A drum-type washing machine according to a main aspect of the present invention includes an outer tub disposed within a housing and configured to store water, a drum disposed within the outer tub and rotatable about a horizontal axis or a rotation axis inclined relative to the horizontal direction and configured to store laundry, a heater for heating the water stored in the outer tub, and a control unit for executing a washing operation capable of washing laundry having soiled therein. Here, the control unit, during the washing operation, executes a hot water bleach wash step in which the control unit rotates the drum to wash the laundry in the drum with water containing bleach heated by the heater, and, after the hot water bleach wash step, executes a tub cleaning step in which the control unit rotates the drum within the outer tub containing water at a higher rotation speed than that of the hot water bleach wash step to clean the inner wall surface of the outer tub.

[0009] According to the drum-type washing machine of this aspect, when laundry having dirt or the like attached thereto is washed, the hot water bleaching wash step can effectively decompose the pigment components of the dirt or the like attached to the laundry and effectively sterilize the laundry by using hot water containing bleach. Furthermore, in the tub cleaning step, the inner wall surface of the outer tub after the hot water bleaching wash step is washed, so that dirt or the like that has fallen off the laundry is less likely to remain in the outer tub, and the user is less likely to feel anxious about dirt or the like that has fallen off the laundry.

[0010] In the drum-type washing machine according to this aspect, the control unit may be configured to rotate the drum and perform a washing process, after the tub cleaning process, in the washing operation, to wash the laundry in the drum with water containing detergent.

[0011] According to the above configuration, when the tub cleaning process is performed with laundry still in the drum, even if the laundry in the drum comes into contact with the water used to wash the inner wall of the outer tub, it is subsequently washed with water containing detergent, thereby preventing contamination of the laundry with water after the tub cleaning.

[0012] The above-described configuration may further include an operation unit. In this case, the operation unit may be configured to accept a laundry addition setting for adding laundry. When the operation unit accepts the laundry addition setting, the control unit may be configured to determine whether the addition of laundry has been completed before executing the washing cycle, and to start the washing cycle based on the determination that the addition of laundry has been completed.

[0013] With this configuration, the user can add laundry by setting up additional laundry, and the laundry that does not need to be washed in the hot water bleach washing process can be washed in the washing process together with the laundry that has been washed in the hot water bleach washing process.

[0014] The drum-type washing machine according to this aspect may further include an operation unit. In this case, the operation unit may be configured to receive a tub cleaning additional setting for adding a tub cleaning. When the operation unit receives the tub cleaning additional setting, the control unit may be configured to execute an additional tub cleaning step after the tub cleaning step, in which the drum is rotated in the outer tub filled with water at a rotation speed higher than that of the warm water bleach washing step, thereby cleaning the inner wall surface of the outer tub.

[0015] According to the above configuration, when there is a lot of dirt or the like adhering to the inner wall surface of the outer tub, the user can thoroughly wash the inner wall surface of the outer tub by setting the additional tub cleaning function. This makes it even less likely for the user to feel anxious about dirt or the like that falls off the laundry.

[0016] When the above configuration is used, the control unit can be configured to store more water in the outer tank during the additional tank cleaning process by supplying water from a water supply device than during the tank cleaning process, and / or to extend the operating time for which the drum rotates than during the tank cleaning process.

[0017] With this configuration, the inner wall surface of the outer tub can be washed more thoroughly in the additional tub cleaning step than in the tub cleaning step, thereby fully satisfying the user's desire to add tub cleaning. [Effects of the Invention]

[0018] According to the present invention, it is possible to provide a drum type washing machine that can satisfactorily wash laundry having soiling thereon.

[0019] The effects and significance of the present invention will become more apparent from the following description of the embodiments, however, the following embodiment is merely an example of how the present invention can be implemented, and the present invention is not limited to the following embodiment. [Brief explanation of the drawings]

[0020] [Figure 1] FIG. 1 is a side cross-sectional view showing the configuration of a drum-type washing machine according to an embodiment. [Figure 2] FIG. 2 is a block diagram showing a configuration of a drum type washing machine according to an embodiment. [Figure 3] FIG. 3 is a flowchart showing the control operation of the control unit in the washing operation of the soiled laundry course according to the embodiment. [Figure 4] FIG. 4 is a flowchart showing the control operation of the control unit in the warm water bleach washing step according to the embodiment. [Figure 5] FIG. 5 is a flowchart showing the control operation of the control unit in the tank cleaning process according to the embodiment. [Figure 6] FIG. 6 is a diagram schematically illustrating a state in which the drum rotates in the tank cleaning step according to the embodiment. [Figure 7] FIG. 7 is a flowchart showing the control operation of the control unit in the additional tank cleaning step according to the embodiment. [Figure 8] FIG. 8 is a flowchart showing the control operation of the control unit in the washing operation of the soiled laundry course according to the modified example. DETAILED DESCRIPTION OF THE INVENTION

[0021] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A drum-type washing machine according to an embodiment of the present invention will be described below with reference to the drawings.

[0022] FIG. 1 is a side cross-sectional view showing the configuration of a drum-type washing machine 1. As shown in FIG.

[0023] The drum type washing machine 1 has a rectangular housing 10. A circular loading opening 11 through which laundry is loaded is formed on the front of the housing 10. The loading opening 11 is covered by a door 12 that can be opened and closed.

[0024] An outer tub 20 having a substantially cylindrical shape is disposed within the housing 10. The outer tub 20 is elastically supported by a plurality of dampers 21 and springs 22. A horizontal-axis drum 23 is rotatably disposed within the outer tub 20. The drum 23 rotates around a horizontal axis. The drum 23 has a circular opening 23a on its front surface. The drum 23 may rotate around an inclined axis that is inclined relative to the horizontal direction.

[0025] The outer tub 20 has a circular opening 20a in front of the opening 23a of the drum 23. The outer tub 20 includes an annular packing 24 made of an elastic material provided on the periphery of the opening 20a. The packing 24 is connected to the periphery of the input port 11. The periphery of the closed door 12 comes into contact with the packing 24, and the space between the input port 11 and the door 12 is watertight.

[0026] A large number of dewatering holes 23b are formed on the inner peripheral surface of the drum 23. In addition, three baffles 25, each having a substantially triangular prism shape, are provided on the inner peripheral surface of the drum 23 at equal intervals in the circumferential direction.

[0027] A drive motor 30 is disposed behind the outer tub 20, generating torque for rotating the drum 23. The drive motor 30 is, for example, an outer rotor DC brushless motor. During the washing and rinsing cycles, the drive motor 30 rotates the drum 23 at a rotation speed at which the centrifugal force acting on the laundry inside the drum 23 is smaller than the gravity, causing the laundry to tumble. On the other hand, during the spin cycle, the drive motor 30 rotates the drum 23 at a rotation speed at which the centrifugal force acting on the laundry inside the drum 23 is much larger than the gravity, causing the laundry to stick to the inner circumferential surface of the drum 23.

[0028] A tubular drain outlet 20b is formed at the bottom of the outer tub 20. A drain unit 40, which drains water from the outer tub 20, is connected to the drain outlet 20b. The drain unit 40 is composed of a drain valve 41, a drain hose 42, and a drain filter 43. The drain filter 43 is connected to the lower end of the drain outlet 20b. The drain valve 41 is provided downstream of the drain filter 43 and includes, for example, a valve and a torque motor for opening and closing the valve. The drain hose 42 is connected to the drain valve 41. When the drain valve 41 is opened, water stored in the outer tub 20 is discharged outside the machine through the drain outlet 20b, the drain filter 43, and the drain hose 42. Foreign matter such as lint is captured by the drain filter 43.

[0029] A water supply device 50 is disposed in the upper part of the housing 10. The water supply device 50 supplies water into the outer tub 20. The water supply device 50 also functions as an automatic detergent dispenser, and automatically dispenses liquid detergent and liquid fabric softener into the outer tub 20.

[0030] The water supply device 50 includes a water supply valve unit 51, a water injection unit 52, and a nozzle unit 53.

[0031] The water supply valve unit 51 includes a water supply valve 110, a first water supply hose 120, and a second water supply hose 130. The water supply valve 110 has a first valve 111 and a second valve 112. A water supply port 113 of the water supply valve 110 is connected to a water faucet via a connecting hose (not shown).

[0032] The inlet of the first water supply hose 120 is connected to the first valve 111, and the inlet of the second water supply hose 130 is connected to the second valve 112. When the first valve 111 is opened, water flows into the first water supply hose 120, and when the second valve 112 is opened, water flows into the second water supply hose 130.

[0033] The water injection unit 52 includes a water injection port member 140 that opens at the front, a liquid agent tank section 150 that is accommodated in the water injection port member 140 so that it can be pulled out, a water channel forming member 160 that is arranged on the upper surface of the water injection port member 140, and a pump unit 170 that is arranged on the rear surface of the water injection port member 140.

[0034] A water inlet 141 is formed at the bottom of the water inlet member 140. A water inlet pipe 54 extending from the water inlet 141 is connected to the outer tub 20.

[0035] The liquid agent tank section 150 has a detergent tank 151 for storing liquid detergent and a fabric softener tank 152 for storing liquid fabric softener. The liquid agent tank section 150 also has a liquid agent storage section 153 that can store liquid agents such as detergent and bleach for one washing run. The liquid agent storage section 153 has an opening on the top surface as an inlet.

[0036] The liquid agent tank section 150 is accommodated in the water inlet member 140 through an accommodation port 13 provided on the front surface of the housing 10. A lid 154 that closes the accommodation port 13 is provided on the front surface of the liquid agent tank section 150. By pulling out the liquid agent tank section 150 from the water inlet member 140, the detergent tank 151 and the fabric softener tank 152 can be refilled with liquid detergent and liquid fabric softener, and the liquid agent can be poured into the liquid agent accommodation section 153.

[0037] Inside the water channel forming member 160, a first water channel to which the outlet of the first water supply hose 120 is connected and a second water channel to which the outlet of the second water supply hose 130 is connected are formed.

[0038] The pump unit 170 includes a detergent pump 171 that supplies the liquid detergent in the detergent tank 151 into the first water passage, and a fabric softener pump 172 that supplies the fabric softener in the fabric softener tank 152 into the first water passage (see FIG. 3).

[0039] Water supplied from the first water supply hose 120 to the water channel forming member 160 flows through the first water channel and is discharged to the bottom of the water inlet member 140, and is supplied into the outer tank 20 via the water inlet 141 and the water inlet pipe 54.

[0040] When liquid detergent or liquid fabric softener is automatically dispensed into the outer tub 20, the liquid detergent or liquid fabric softener is introduced into the first water passage from the liquid agent tank 150 by the pump unit 170 before the first valve 111 is opened. The liquid detergent or liquid fabric softener is mixed with water flowing through the first water passage and supplied into the outer tub 20.

[0041] Furthermore, a portion of the water discharged from the first water channel of the water channel forming member 160 into the water inlet member 140 reaches the water inlet 141 via the liquid agent storage section 153. Therefore, if a liquid agent such as bleach is stored in the liquid agent storage section 153, the liquid agent is washed away by the water and supplied into the outer tub 20 via the water inlet 141 and the water inlet pipe 54.

[0042] Water supplied from the second water supply hose 130 to the water channel forming member 160 flows through the second water channel and is sent to the nozzle unit 53.

[0043] Nozzle unit 53 includes a shower nozzle 180 arranged inside the upper part of packing 24, and a water supply hose 181 extending from the second water channel of water channel forming member 160 and connected to shower nozzle 180.

[0044] The water outlet of shower nozzle 180 faces downward and rearward, i.e., toward the bottom of drum 23. Water flowing out from the second waterway passes through water supply hose 181 to shower nozzle 180, and is then sprayed in a shower-like manner from the outlet of shower nozzle 180 toward the inside of drum 23. This causes water to splash on the laundry inside drum 23, making it easier for the water to penetrate into the laundry.

[0045] FIG. 2 is a block diagram showing the configuration of the drum type washing machine 1. As shown in FIG.

[0046] In addition to the above-described configuration, the drum type washing machine 1 includes a control unit 201, a memory unit 202, an operation unit 203, a display unit 204, a sound output unit 205, a water level sensor 206, a motor drive unit 207, a water supply drive unit 208, a drain drive unit 209, a pump drive unit 210, a heater drive unit 211, and a door lock device 212.

[0047] The operation unit 203 includes a power button for turning the power on and off, a course selection button for selecting an operation course from a plurality of operation courses related to the washing operation, and a start button for starting and pausing the washing operation. The operation unit 203 outputs an input signal to the control unit 201 according to the button operated by the user.

[0048] The display unit 204 includes a display such as a light-emitting element such as an LED or a liquid crystal panel, and displays the selected operation course, the progress of the washing operation, notifies of abnormalities, etc. according to a control signal from the control unit 201.

[0049] The operation unit 203 and the display unit 204 may be configured as an operation display unit such as a touch panel.

[0050] The sound output unit 205 includes a speaker, and outputs sounds such as voice and alarm sounds from the speaker.

[0051] The water level sensor 206 detects the water level in the outer tub 20. The water level sensor 206 is connected, for example, via a hose to an air trap provided at the bottom of the outer tub 20 or at the drain outlet 20b, and detects the air pressure in the air trap, which changes depending on the water level in the outer tub 20. The water level sensor 206 outputs a frequency signal to the control unit 201 as a water level signal having a value according to the detected water level.

[0052] The motor drive unit 207 drives the drive motor 30 in accordance with a control signal from the control unit 201. The motor drive unit 207 includes a rotation sensor that detects the rotation speed of the drive motor 30, an inverter circuit, etc., and adjusts the drive power so that the drive motor 30 rotates at the rotation speed set by the control unit 201. Furthermore, the motor drive unit 207 includes a current sensor that detects the current flowing through the drive motor 30.

[0053] The water supply driving unit 208 drives the first valve 111 and the second valve 112 of the water supply valve 110 in accordance with a control signal from the control unit 201. The drain driving unit 209 drives the drain valve 41 in accordance with a control signal from the control unit 201. The pump driving unit 210 drives the detergent pump 171 and the fabric softener pump 172 of the pump unit 170 in accordance with a control signal from the control unit 201. The heater driving unit 211 drives the heater 60 in accordance with a control signal from the control unit 201.

[0054] The door lock device 212 locks and unlocks the door 12 in accordance with a control signal from the control unit 201 .

[0055] The storage unit 202 includes an EEPROM, a RAM, etc. Programs for executing various operation courses of the washing operation are stored in the storage unit 202. The storage unit 202 also stores various parameters and various control flags used in executing these programs.

[0056] The control unit 201 includes a CPU, etc., and controls the display unit 204, sound output unit 205, motor drive unit 207, water supply drive unit 208, drain drive unit 209, pump drive unit 210, heater drive unit 211, door lock device 212, etc. based on signals from the operation unit 203, water level sensor 206, etc., in accordance with a program stored in the memory unit 202.

[0057] In the drum type washing machine 1, various operation courses are performed under the control of the control unit 201 based on the user's operation of the operation unit 203. In the washing operation, a washing step, an intermediate spin-drying step, a rinsing step, and a final spin-drying step are performed in this order. Depending on the operation course, the rinsing step and the intermediate spin-drying step may be performed two or more times.

[0058] In the washing process, detergent-containing water is filled in the outer tub 20 up to a wash water level set according to the load of laundry in the drum 23. Then, the drum 23 is repeatedly rotated forward and backward, causing the laundry immersed in the detergent-containing water to tumble. The detergent-containing water penetrates into the laundry, and the power of the detergent and the mechanical force of the tumbling remove dirt adhering to the surface and interior of the laundry.

[0059] In the rinsing process, the outer tub 20 is filled with water up to a rinse level corresponding to the load, and the drum 23 rotates repeatedly in both forward and reverse directions to tumble the laundry. This causes the detergent contained in the laundry to be expelled together with the water, rinsing the laundry.

[0060] In the intermediate spin-drying step and the final spin-drying step, drive motor 30 rotates in one direction at high speed, causing drum 23 to rotate in one direction at a rotation speed at which the centrifugal force acting on the laundry inside drum 23 is much greater than gravity. The centrifugal force presses the laundry against the inner circumferential surface of drum 23, causing it to be dewatered. In the final spin-drying step, drum 23 rotates at a rotation speed higher than that in the intermediate spin-drying step.

[0061] Before the washing process, a load detection process is performed to detect the laundry load. Drum 23 rotates at a rotation speed that tumbles the laundry inside drum 23, and the load applied to drum 23 during rotation is detected from the value of the current flowing through drive motor 30. The greater the laundry load, the greater the load on drum 23 and the greater the value of the current flowing through drive motor 30. Control unit 201 determines the load based on the magnitude of the current value, and based on the load, determines the wash water level and rinse water level, as well as the amount of detergent to be dispensed in the washing process and the amount of fabric softener to be dispensed in the rinsing process. The greater the load, the higher the wash water level and rinse water level, and the greater the amount of detergent and fabric softener to be dispensed.

[0062] In the water supply process carried out in the washing process and the rinsing process, the water supply device 50 supplies water into the outer tub 20 through the water injection pipe 54 and also supplies water into the outer tub 20 through the shower nozzle 180. In addition, in the water supply process of the washing process, the water supply device 50 automatically supplies water and also dispenses liquid detergent into the detergent tank 151, and in the water supply process of the rinsing process, the water supply device 50 automatically supplies water and also dispenses liquid fabric softener into the fabric softener tank 152. If the rinsing process is carried out two or more times, the liquid fabric softener is dispensed in the final rinsing process.

[0063] The operation courses executed by the drum type washing machine 1 of this embodiment include a dirty laundry course. In the washing operation of the dirty laundry course, laundry such as baby cloth diapers and underwear contaminated with dirt (excrement), and laundry such as clothes and towels contaminated with vomit are washed. The washing operation of the dirty laundry course will be described in detail below.

[0064] In the washing operation of the soiled laundry course, a pre-washing operation consisting of a hot water bleaching washing step, an intermediate spin-drying step, a rinsing step, a tub cleaning step and an intermediate spin-drying step, and a main washing operation consisting of a washing step, an intermediate spin-drying step, a rinsing step and a final spin-drying step are carried out in order.

[0065] After putting laundry with dirt and the like attached into drum 23, the user selects the dirty laundry course using the course selection button on operation unit 203. At this time, if the laundry has a lot of dirt and the like attached, the user operates the buttons on operation unit 203 to set an additional tub cleaning to add a tub cleaning. Also, if the user wants to add laundry with normal soiling and perform a main wash operation, the user operates the buttons on operation unit 203 to set an additional laundry. Thereafter, the user presses the start button on operation unit 203. This starts the wash operation of the dirty laundry course.

[0066] When the operation unit 203 receives the setting for adding tub cleaning or adding laundry, the control unit 201 stores in the storage unit 202 the fact that the setting for adding tub cleaning or adding laundry has been performed.

[0067] FIG. 3 is a flowchart showing the control operation of the control unit 201 during the washing operation of the soiled laundry course.

[0068] 3, after locking door 12 using door lock device 212 (S101), control unit 201 executes a load amount detection step (S102). This detects the load amount of laundry in drum 23. In this load amount detection step, the amount of bleach to be dispensed is determined based on the load amount.

[0069] The control unit 201 causes the display unit 204 to display the amount of bleach to be dispensed (S103). The user dispenses the amount of bleach to be dispensed displayed on the display unit 204 into the liquid storage unit 153 of the liquid tank unit 150.

[0070] Next, the control unit 201 waits for a time required for adding bleaching agent, and then executes the warm water bleach washing process (S104).

[0071] FIG. 4 is a flowchart showing the control operation of the control unit 201 in the warm water bleach washing step.

[0072] 4, the control unit 201 opens the first valve 111 and the second valve 112, and causes the water supply device 50 to supply water into the outer tub 20 (S201). At this time, the bleaching agent in the liquid agent storage unit 153 is supplied together with water into the outer tub 20. The water containing the bleaching agent is stored in the outer tub 20.

[0073] When the water level in the outer tub 20 reaches the wash water level set according to the load amount (S202: YES), the control unit 201 closes the first valve 111 and the second valve 112 and stops the supply of water to the outer tub 20 (S203).

[0074] The user may also pour bleach directly into the drum 23. Alternatively, the user may apply bleach to soiled areas of the laundry before pouring it into the drum 23. In such cases, water containing bleach is also stored in the outer tub 20.

[0075] Control unit 201 operates drive motor 30 to rotate drum 23 alternately clockwise and counterclockwise, with stops in between (S204). At this time, drum 23 rotates at a predetermined washing rotation speed (for example, about 50 rpm) at which laundry is tumbling.

[0076] Furthermore, the control unit 201 operates the heater 60 (S205), whereby the water containing the bleaching agent in the outer tub 20 is heated.

[0077] In addition, the control unit 201 may operate the heater 60 from the point at which the heater 60 is submerged in water while water is being supplied into the outer tub 20, or may start rotating the drum 23 from the point at which the inside of the drum 23 is submerged in water.

[0078] The control unit 201 monitors whether a predetermined washing time has elapsed (S206). The washing time is set to a time (e.g., 5 minutes) such that the water temperature in the outer tub 20 exceeds 40°C before the washing time has elapsed, even when the water supply temperature is low, such as in winter. If the initial water temperature in the outer tub 20 is high and the water temperature reaches an upper limit temperature (e.g., 60°C) before the washing time has elapsed, the heater 60 is controlled to turn on and off, and the water temperature is maintained at the upper limit temperature. The water temperature in the outer tub 20 is detected by a temperature sensor (not shown) located at the bottom of the outer tub 20.

[0079] The laundry is beaten and washed by tumbling in the drum 23. At this time, the warm water containing bleach acts on the laundry, effectively breaking down the pigment components of the dirt adhering to the laundry and effectively disinfecting the laundry.

[0080] When the washing time has elapsed (S206: YES), the control unit 201 stops the drive motor 30 to stop the drum 23 (S207). Furthermore, the control unit 201 stops the heater 60 (S208). Then, the control unit 201 opens the drain valve 41 to drain water from the outer tub 20 (S209). In this way, the warm water bleach washing process is completed.

[0081] In addition, the control unit 201 may stop the drum 23 and the heater 60 when the water temperature in the outer tub 20 reaches a predetermined temperature (for example, 60°C) instead of when the washing time has elapsed, or when a predetermined time has elapsed since the water temperature reached the predetermined temperature.

[0082] Returning to Fig. 3, the control unit 201 executes the intermediate spin-drying step (S105) and then executes the rinsing step (S106), thereby removing the bleaching agent contained in the laundry together with the water.

[0083] Next, the control unit 201 executes the tank cleaning step (S107).

[0084] Fig. 5 is a flowchart showing the control operation of control unit 201 in the tank cleaning process. Fig. 6 is a diagram showing a schematic view of the state when drum 23 rotates in the tank cleaning process.

[0085] 5, control unit 201 opens first valve 111 and second valve 112, and causes water supply device 50 to supply water into outer tub 20 (S301). When the water level in outer tub 20 reaches the first water level (S302: YES), control unit 201 closes first valve 111 and second valve 112, and stops the supply of water into outer tub 20 (S303). The first water level is set, for example, to a water level that reaches drum 23 but is lower than the wash water level.

[0086] Next, the control unit 201 operates the drive motor 30 to rotate the drum 23 in one direction at a first rotation speed (S304). The first rotation speed is set to a rotation speed that is higher than the washing rotation speed in the hot water bleach washing step and that causes the laundry to stick to the inner circumferential surface of the drum 23 by centrifugal force. For example, the first rotation speed is set to 100 rpm or higher.

[0087] As shown in Fig. 6, when drum 23 rotates at the first rotation speed, water accumulated at the bottom of outer tub 20 is scooped up by rotating drum 23 and splashed from the outer periphery of drum 23 onto the inner wall surface of outer tub 20, particularly onto the upper part of the inner wall surface. This washes the entire inner wall surface of outer tub 20. Therefore, during the warm water bleach wash process, water containing dirt and bleaching agent that has fallen from the laundry splashes onto the inner wall surface of outer tub 20, and even if dirt or bleaching agent is attached to the inner wall surface, the bleaching agent and dirt are washed off.

[0088] When a first time period (e.g., five minutes) has elapsed since the start of rotation of the drum 23 (S305: YES), the control unit 201 stops the drive motor 30 to stop the drum 23 (S306). Then, the control unit 201 opens the drain valve 41 to drain water from the outer tub 20 (S307). This completes the tub cleaning process.

[0089] Returning to FIG. 3, the control unit 201 executes the intermediate spin-drying step (S108), which causes the laundry to be first dewatered.

[0090] Next, the control unit 201 determines whether or not additional tank cleaning is set (S109). If additional tank cleaning is set (S109: YES), the control unit 201 executes an additional tank cleaning process (S110).

[0091] FIG. 7 is a flowchart showing the control operation of the control unit 201 in the additional tank cleaning step.

[0092] 7, the control unit 201 opens the first valve 111 and the second valve 112, and causes the water supply device 50 to supply water into the outer tub 20 until the water level in the outer tub 20 reaches the second water level (S401 to S403). The second water level is a water level higher than the first water level in the tub cleaning process, and is set to, for example, the highest water level set according to the load amount.

[0093] Next, the control unit 201 operates the drive motor 30 to rotate the drum 23 in one direction at a second rotation speed (S404). The second rotation speed is set to a rotation speed higher than the washing rotation speed in the hot water bleach wash step, so that the laundry adheres to the inner circumferential surface of the drum due to centrifugal force. For example, the second rotation speed is set to 100 rpm or higher. The second rotation speed may or may not be the same as the first rotation speed.

[0094] As the drum 23 rotates at the second rotation speed, the water accumulated at the bottom of the outer tub 20 is scooped up by the rotating drum 23 and splashed from the outer peripheral surface of the drum 23, and is then sprayed onto the inner wall surface of the outer tub 20, particularly onto the upper part of the inner wall surface, as in the tub cleaning process (see FIG. 6). As a result, the entire inner wall surface of the outer tub 20 is washed.

[0095] The control unit 201 monitors whether or not a second time has elapsed since the start of rotation of the drum 23 (S405). The second time is set to a time (for example, 10 minutes) longer than the first time.

[0096] When the second time period has elapsed (S405: YES), the control unit 201 stops the drive motor 30 to stop the drum 23 (S406). Then, the control unit 201 opens the drain valve 41 to drain water from the outer tub 20 (S407). In this way, the additional tub cleaning process is completed.

[0097] Returning to FIG. 3, the control unit 201 executes the intermediate spin-drying step (S111), thereby spinning the laundry first.

[0098] When the control unit 201 has completed the additional tub cleaning step and the intermediate spin-drying step, or when it determines in S109 that the additional tub cleaning setting has not been made (S109: NO), it determines whether or not the additional laundry setting has been made (S112). Then, when the additional laundry setting has been made (S112: YES), the control unit 201 unlocks the door 12 using the door lock device 212 (S113). At this time, the control unit 201 outputs a buzzer sound, voice, or the like from the sound output unit 205. This notifies the user that the pre-wash operation has ended.

[0099] The user opens door 12 and places laundry that is normally soiled and does not require pre-washing, i.e., washing in the hot water bleach wash step, into drum 23. Then, the user closes door 12 and presses the start button on operation unit 203. Pressing the start button is a sign that adding laundry has been completed. Note that the completion of adding laundry may also be indicated by a door detection switch (not shown) detecting that door 12 has been closed.

[0100] When the control unit 201 determines that adding laundry to the drum 23 is complete (S114: YES), it locks the door 12 using the door lock device 212 (S115) and then executes a load amount detection process (S116). This detects the load amount of laundry in the drum 23. At this time, the laundry that was first loaded into the drum 23 and subjected to the pre-wash operation is wet. Therefore, a load amount that is larger than the actual load amount is detected. Therefore, the control unit 201 corrects the detected load amount to decrease, and determines the wash water level and rinse water level, as well as the amount of detergent and fabric softener to be added, based on the corrected load amount. The larger the load amount of laundry that was initially loaded, the greater the amount that is reduced by the correction.

[0101] If no laundry is added and the load amount detection step of S116 is not performed, the wash water level and rinse water level are determined based on the load amount detected in the load amount detection step of S102, and the amounts of detergent and fabric softener to be added are also determined.

[0102] When the load amount detection step is completed, or when it is determined in S112 that the setting for adding laundry has not been performed (S112: NO), the control unit 201 starts the main wash operation and sequentially executes the washing step, the intermediate spin-drying step, the rinsing step, and the final spin-drying step (S117 to S120). In the washing step, the water supply device 50 supplies water to the outer tub 20 up to the wash water level, and detergent is automatically dispensed. The laundry is tumbled in the water containing detergent by the rotation of the drum 23, and is washed. In the rinsing step, the water supply device 50 supplies water to the outer tub 20 up to the rinse water level, and fabric softener is automatically dispensed. The laundry is tumbled in the water containing fabric softener by the rotation of the drum 23, and is rinsed.

[0103] When the final spin-drying step is completed, the control unit 201 unlocks the door 12 using the door lock device 212 (S121). Thus, the washing operation of the soiled laundry course is completed. The user removes the laundry from the drum 23.

[0104] The drum type washing machine 1 of this embodiment may also include a drying device for drying laundry. In this case, the drying device includes, for example, a circulation path connected to the outer tub 20. A blower fan, a cooler, and a heater are arranged in the circulation path. Air heated by the heater circulates between the outer tub 20 and the circulation path by the operation of the blower fan, and the laundry in the drum 23 dries. The air returning to the circulation path from the outer tub 20 is cooled and dehumidified by the cooler before being heated by the heater.

[0105] In this way, when drum type washing machine 1 is a drum type washer-dryer equipped with a drying function, when the final spin-drying step is completed in S120 during the washing operation of the soiled laundry course in Fig. 3, control unit 201 executes a drying step in which the drying device dries the laundry in drum 23. Then, when the drying step is completed, control unit 201 unlocks door 12 using door lock device 212 in S121.

[0106] Drum type washing machine 1 can operate a tub cleaning course that includes a tub cleaning step similar to the tub cleaning step of the soiled laundry course, and that uses a tub cleaner to clean drum 23 and outer tub 20 when laundry is not loaded. In this case, control unit 201 causes display unit 204 to issue a notification urging the user to operate the tub cleaning course when a predetermined period of time has passed since the previous operation of the tub cleaning course, or when a predetermined number of washing operations have been performed. When the soiled laundry course is performed, control unit 201 may shorten the predetermined period of time or reduce the predetermined number of washing operations, compared to when the soiled laundry course washing operation is not performed, to prevent odor generation.

[0107] <Effects of the embodiment> According to this embodiment, the control unit 201 executes a washing operation of a soiled laundry course capable of washing laundry having soiled dirt therein. In this washing operation, a warm water bleach wash step is executed in which the drum 23 is rotated and the laundry in the drum 23 is washed with water containing bleach and heated by the heater 60. After the warm water bleach wash step, a tub cleaning step is executed in which the drum 23 is rotated in the outer tub 20 filled with water at a higher rotation speed than that in the warm water bleach wash step to clean the inner wall surface of the outer tub 20.

[0108] According to this configuration, when laundry with dirt or the like attached is washed, the hot water bleaching wash step can effectively decompose the pigment components of the dirt or the like attached to the laundry and effectively sterilize the laundry by using hot water containing bleach. Furthermore, in the tub cleaning step, the inner wall surface of the outer tub 20 after the hot water bleaching wash step is washed, so that dirt or the like that has fallen off the laundry is less likely to remain in the outer tub 20, and the user is less likely to feel anxious about dirt or the like that has fallen off the laundry.

[0109] Furthermore, according to this embodiment, in the washing operation of the dirty course, the control unit 201 rotates the drum 23 after the tub cleaning process and executes a washing process in which the laundry in the drum 23 is washed with water containing detergent.

[0110] With this configuration, even if the laundry in drum 23 comes into contact with the water used to wash the inner wall surface of outer tub 20, it is subsequently washed with water containing detergent. This prevents the laundry from being contaminated by water after tub cleaning.

[0111] Furthermore, according to this embodiment, when the operation unit 203 accepts a setting to add laundry, the control unit 201 determines whether the addition of laundry has been completed before executing the washing process, and starts the washing process based on the determination that the addition of laundry has been completed.

[0112] According to this configuration, by the user setting up additional laundry, laundry that does not need to be washed in the hot water bleach washing process can be washed in the washing process together with laundry that has been washed in the hot water bleach washing process.

[0113] Furthermore, according to this embodiment, when the operation unit 203 accepts an additional tub cleaning setting, the control unit 201 executes an additional tub cleaning process after the tub cleaning process, in which the drum 23 is rotated in the outer tub 20 filled with water at a higher rotation speed than in the warm water bleach washing process, thereby washing the inner wall surface of the outer tub 20.

[0114] With this configuration, when there is a lot of dirt or the like adhering to the inner wall surface of the outer tub 20, the user can thoroughly wash the inner wall surface of the outer tub 20 by setting the additional tub cleaning function. This makes it even less likely that the user will be worried about dirt or the like that falls off the laundry.

[0115] Furthermore, according to this embodiment, in the additional tank cleaning process, the control unit 201 stores more water in the outer tank 20 by supplying water from the water supply device 50 than in the tank cleaning process, and makes the operating time for which the drum 23 rotates longer than in the tank cleaning process.

[0116] According to this configuration, the inner wall surface of the outer tub 20 can be washed more thoroughly in the additional tub cleaning step than in the tub cleaning step, thereby fully satisfying the user's desire to add tub cleaning.

[0117] Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications to the embodiments of the present invention are possible.

[0118] For example, in the warm water bleach wash step of the soiled laundry wash cycle, the water supply device 50 may supply water, bleach, and detergent into the outer tub 20. In this case, the laundry in the drum 23 is washed with water containing the bleach and detergent stored in the outer tub 20. This increases the amount of detergent used per wash cycle, but improves the cleaning effect of the laundry.

[0119] Furthermore, water supply device 50 may be configured to automatically dispense bleach as well as detergent and fabric softener. In this case, liquid agent tank section 150 is provided with a bleach tank that stores liquid bleach instead of liquid agent storage section 153. Furthermore, pump unit 170 is provided with a bleach pump that sends bleach in the bleach tank to the first water channel of water channel forming member 160.

[0120] Furthermore, in the above embodiment, in the additional tub cleaning step of the soiled laundry course washing operation, the control unit 201 stores more water in the outer tub 20 than in the tub cleaning step, and makes the operating time for which the drum 23 rotates longer than in the tub cleaning step. However, in the additional tub cleaning step, the control unit 201 may simply store more water in the outer tub 20 than in the tub cleaning step, or may simply make the operating time for which the drum 23 rotates longer than in the tub cleaning step.

[0121] Furthermore, the setting for adding tub cleaning may be disabled during the soiled laundry course washing operation, in which case the processes of S109 to S111 in FIG.

[0122] Furthermore, the setting for adding laundry may be disabled during the washing operation of the soiled laundry course, in which case the processes of S112 to S116 in FIG.

[0123] Furthermore, when the setting for adding laundry is disabled, the washing operation of the soiled laundry course may be changed as shown in FIG.

[0124] That is, when executing the bleach dispenser step of S104, the control unit 201 supplies not only bleach but also detergent into the outer tub 20 using the water supply device 50 when supplying water in S201 of Fig. 4. The wash time is then made longer than in the above embodiment. Thereafter, when executing the rinse step of S106, the control unit 201 supplies fabric softener into the outer tub 20 using the water supply device 50 when supplying water into the outer tub 20.

[0125] When the rinsing cycle is completed, the control unit 201 performs a final spin cycle (S131). Thereafter, the control unit 201 unlocks the door 12 using the door lock device 212 (S132) and waits for the laundry to be removed (S133). For example, the control unit 201 determines that the laundry has been removed when the door 12 is opened and then closed. When the control unit 201 determines that the laundry has been removed (S133: YES), the control unit 201 locks the door 12 using the door lock device 212 (S134) and performs the tub cleaning cycle (S135). Furthermore, when the tub cleaning additional setting is set (S136: YES), the control unit 201 performs the additional tub cleaning cycle (S137). Thereafter, the control unit 201 unlocks the door 12 using the door lock device 212 (S138).

[0126] 8, only the main wash operation is performed in which the washing step is replaced with the hot water bleaching step. In this wash operation, the tub cleaning step and the additional tub cleaning step are performed after the laundry is removed from the drum 23. Therefore, the water used to wash the inner wall surface of the outer tub 20 does not come into contact with the laundry.

[0127] In addition, the embodiments of the present invention can be modified in various ways as appropriate within the scope of the technical ideas set forth in the claims. [Explanation of symbols]

[0128] 1. Drum washing machine 10. Cabinet 20 Outer tank 23 Drums 50 Water supply equipment 60 Heater 201 Control Unit 203 Operation section

Claims

1. an outer tank disposed within the housing and configured to store water; a drum disposed in the outer tub so as to be rotatable about a horizontal axis or a rotation axis inclined relative to the horizontal direction, and configured to accommodate laundry; a heater for heating the water stored in the outer tank; a control unit that executes a washing operation that can wash laundry having soiled thereon, The control unit, during the washing operation, a hot water bleach wash step in which the drum is rotated and the laundry in the drum is washed with water containing bleach and heated by the heater; After the hot water bleach washing step, a tub cleaning step is carried out in which the drum is rotated in the outer tub filled with water at a rotation speed higher than that in the hot water bleach washing step, thereby cleaning the inner wall surface of the outer tub. A drum type washing machine comprising:

2. The drum type washing machine according to claim 1, The control unit, in the washing operation, after the tub cleaning step, rotates the drum and executes a washing step of washing the laundry in the drum with water containing detergent. A drum type washing machine characterized by the above.

3. The drum type washing machine according to claim 2, Further provided with an operation unit, the operation unit accepts a laundry addition setting for adding laundry, When the operation unit receives the laundry addition setting, the control unit Before executing the washing step, it is determined whether or not the addition of laundry has been completed; starting the washing process based on a determination that the addition of laundry has been completed; A drum type washing machine characterized by the above.

4. The drum type washing machine according to any one of claims 1 to 3, Further provided with an operation unit, The operation unit receives a tank cleaning addition setting for adding a tank cleaning, When the operation unit receives the additional tub cleaning setting, the control unit executes an additional tub cleaning process after the tub cleaning process, in which the drum is rotated in the outer tub filled with water at a rotation speed higher than that in the warm water bleach washing process, thereby cleaning the inner wall surface of the outer tub. A drum type washing machine characterized by the above.

5. The drum type washing machine according to claim 4, In the additional tank cleaning process, the control unit supplies water from a water supply device to store more water in the outer tank than in the tank cleaning process, and / or makes the operating time for rotating the drum longer than in the tank cleaning process. A drum type washing machine characterized by the above.

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