Clothes Processing Equipment

Abstract

To provide a clothing treatment device which improves finish of laundry by removing foam after main washing treatment, in the clothing treatment device for executing a plurality of washing steps.SOLUTION: A clothing treatment device includes: an outer case; a water tub provided inside the outer case; a rotary tub provided in the water tub rotatably; a rotary tub motor for rotationally driving the rotary tub; a water supply passage for supplying water supplied from an external water source to the water tub; a water supply valve for opening / closing the water supply path; a drain path for draining water from the water tub; a drain valve for opening / closing the drain path; and a control device capable of executing a washing operation containing a washing step, a rinsing step and a dewatering step by controlling the drive of the rotary tub motor, opening / closing of the water supply valve and opening / closing of the drain valve. The control device can execute pre-washing treatment and main washing treatment executed after the pre-washing treatment, in the washing step, and it executes foam removal treatment for performing water supply by opening the water supply valve in a state where the drain valve is open.SELECTED DRAWING: Figure 2

Description

[Technical field]

[0001] An embodiment of the present invention relates to a clothes treatment device. [Background technology]

[0002] Conventionally, for example, when the laundry is highly soiled, a method is known in which the washing performance is efficiently improved by performing a washing process including a pre-wash. In this case, the washing water containing the dirt removed from the laundry by the pre-wash is drained before the main wash is performed, so that for example, twice the amount of detergent required is put into the water tank during the pre-wash so that there is no shortage of detergent during the main wash. In this way, even if the water is drained after the pre-wash, detergent remains in the water tank during the main wash.

[0003] In recent years, washing machines equipped with an automatic detergent dispenser mechanism that can automatically dispense detergent have been developed. By using this automatic dispenser mechanism to automatically dispense the appropriate amount of detergent in each of the multiple washing steps, it has become possible to efficiently dispense the necessary and sufficient amount of detergent in each step and improve the washing performance.

[0004] When multiple wash cycles are performed, dirt from the laundry is gradually removed with each cycle. If detergent is added when the laundry is only slightly dirty, a large amount of foam may be generated. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2012-75505 A Summary of the Invention [Problem to be solved by the invention]

[0006] Therefore, a clothing treatment device that performs a plurality of washing steps is provided, which removes foam after the main washing process to improve the finish of the laundry. [Means for solving the problem]

[0007] The clothes treatment device of the embodiment includes an outer box, a water tank provided inside the outer box, a rotating tank rotatably provided inside the water tank, a rotating tank motor for rotating the rotating tank, a water supply path for supplying water from an external water source to the water tank, a water supply valve for opening and closing the water supply path, a drainage path for draining water from the water tank, a drainage valve for opening and closing the drainage path, and a control device capable of performing a washing operation including a washing process, a rinsing process, and a spin-drying process by controlling the driving of the rotating tank motor, the opening and closing of the water supply valve, and the opening and closing of the drainage valve. The control device is capable of performing a pre-wash process and a main wash process performed after the pre-wash process in the washing process, and performs a bubble removal process by opening the water supply valve and supplying water with the drainage valve open. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a front view showing a schematic configuration of an example of a washing machine according to a first embodiment; [Diagram 2] FIG. 1 is a vertical cross-sectional view showing a schematic configuration of an example of a washing machine according to a first embodiment; [Diagram 3] FIG. 1 is a block diagram showing an electrical configuration of an example of a washing machine according to a first embodiment; [Figure 4] A chart showing an overview of a washing operation of an example of a washing machine according to the first embodiment. [Diagram 5] A chart showing an overview of the washing process of an example of a washing machine according to the first embodiment. [Figure 6] A chart showing the operation of each component in a pre-wash process and an intermediate spin-dry process of an example of a washing machine according to a first embodiment. [Figure 7] A chart showing the operation of each component in the main wash process, the foam removal process, and the intermediate spin-dry process of an example of a washing machine according to the first embodiment. [Figure 8] A chart showing the operation of each component in a foam removal process of an example of a washing machine according to the first embodiment. [Figure 9] 1 is a chart showing an example of opening and closing control of a water supply valve in a foam removing process of an example of a washing machine according to a first embodiment. [Figure 10] A chart showing an overview of the rinsing process of the washing machine according to the first embodiment. [Figure 11] 1 is a chart showing the operation of each component in a final rinsing process of an example of a washing machine according to a first embodiment; [Figure 12] FIG. 11 is a schematic diagram showing a water discharge range when a circulation pump of an example of the washing machine according to the first embodiment is operated at a second driving frequency; [Figure 13] FIG. 11 is a schematic diagram showing a water discharge range when a circulation pump of an example of the washing machine according to the first embodiment is operated at a third driving frequency; [Figure 14] A chart showing an example of opening and closing control of a water supply valve in a foam removing process of an example of a washing machine according to another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] Hereinafter, embodiments of the present invention will be described with reference to the drawings. Note that substantially the same elements in each embodiment are denoted by the same reference numerals, and description thereof will be omitted.

[0010] (First embodiment) The first embodiment will be described with reference to Figs. 1 to 13. As shown in Figs. 1 to 3, the washing machine 10 as a clothes treating device includes an outer box 11, a water tub 12, a rotating tub 13, a rotating tub motor 14, a door 15, a bellows 16, a connection port 17, a water supply path 18, a water supply valve 19, a drainage path 20, a drainage valve 21, a circulation path 22, a circulation pump 23, an operation panel 24, a control device 25, and a treating agent injection mechanism 30. In Fig. 1, the installation surface side of the washing machine 10, that is, the vertically lower side, is the lower side of the washing machine 10, and the opposite side of the installation surface, that is, the vertically upper side, is the upper side of the washing machine 10. The left-right direction when the washing machine 10 is viewed from the front is the left-right direction of the washing machine 10. The washing machine 10 is, for example, a horizontal axis type in which the rotation axis of the rotating tub 13 is horizontal, or an oblique axis type inclined downward toward the rear. In this embodiment, the washing machine 10 is an inclined-axis drum washing machine in which the rotation axis of the rotating tub 13 is inclined downward toward the rear.

[0011] The washing machine 10 may or may not have a drying function, for example, a heat pump type or a heater type. The outer box 11 is made of, for example, steel or resin material and has a rectangular box shape as a whole, and constitutes the outer shell of the washing machine 10. An opening 112 through which laundry can be put in and taken out is formed in a front part 111 of the outer box 11.

[0012] The water tub 12 is disposed inside the outer box 11 and is elastically supported by a suspension (not shown). The spin tub 13 is disposed rotatably inside the water tub 12. The water tub 12 and the spin tub 13 are both formed in a cylindrical shape. The water tub 12 has an opening 121 formed at one end of the cylindrical shape, and a water tub end plate 122 is provided at the other end. The opening 121 is located above the water tub end plate 122 in the inclined water tub 12. The water tub 12 and the spin tub 13 function as a washing tub that contains laundry. The spin tub 13 also has a plurality of baffles 133 and a plurality of holes 134. The plurality of baffles 133 are provided inside the cylindrical portion of the spin tub 13, and agitate and stir up laundry such as clothes contained inside the spin tub 13 as the spin tub motor 14 rotates. The holes 134 are formed over the entire inner peripheral wall of the rotating tub 13 and function as water passages through which water flows in and out during the washing, rinsing and spin-drying steps.

[0013] Rotary tub motor 14 is provided on water tub end plate 122 outside water tub 12. Rotary tub motor 14 is, for example, an outer rotor type DC brushless motor. A shaft 141 of rotary tub motor 14 passes through water tub end plate 122 and protrudes into water tub 12, and is fixed to the center of rotary tub end plate 132. Rotary tub motor 14 rotates rotary tub 13 relative to water tub 12. In this case, shaft 141 of rotary tub motor 14, the rotation axis of rotary tub 13, and the center axis of water tub 12 are all aligned. Rotary tub motor 14 is electrically connected to control device 25, and driven at a variable speed under the control of control device 25.

[0014] Door 15 is rotatably provided on front portion 111 of outer case 11 to open and close opening 112. As shown in Fig. 2, door 15 protrudes toward the inside of outer case 11. Bellows 16 connects opening 112 to opening 121 of water tub 12. Laundry such as clothes is put in and taken out of spin tub 13 through openings 121, 131 with door 15 open.

[0015] The connection port 17 is provided on the top surface of the outer box 11 so as to be exposed, for example, at the left rear part. The connection port 17 is connected to an external water source via, for example, a hose. The water supply path 18 is a path that connects the connection port 17 to the water tank 12 and the rotating tank 13. One end of the water supply path 18 is connected to a water supply valve 19, and the other end is connected to the upper part of the water tank 12. In this embodiment, the downstream end of the water supply path 18 is connected to a water inlet 124 provided near an opening 121 at the upper part of the water tank 12. The water supply valve 19 is an opening / closing valve for liquid that can be electromagnetically opened and closed. The water supply valve 19 is electrically connected to the control device 25, and opens and closes under the control of the control device 25. The connection port 17, the water supply path 18, and the water supply valve 19 together constitute a water supply mechanism that receives water from an external water supply source, such as a water supply, and supplies water to the water tank 12.

[0016] Although not shown in detail, water supply path 18 and water supply valve 19 each include a plurality of water supply paths and a plurality of water supply valves according to a plurality of, in this case, two types of laundry treatment agents. First water supply path 181 and second water supply path 182 are paths through which laundry treatment agents, for example, detergent and fabric softener, are soaked in water from an external water source and supplied to water tub 12. First water supply valve 191 and second water supply valve 192 open and close first water supply path 181 and second water supply path 182, respectively. Note that first water supply valve 191 and second water supply valve 192 may be substantially realized as a single unit using a three-way valve or the like.

[0017] Note that a plurality of water inlets may be provided in the water tank 12, and a plurality of water supply paths 18 may be provided corresponding to the water inlets, or one water supply path 18 may be branched downstream. For example, a second water inlet may be provided in the upper part of the water tank 12, rearward of the water inlet 124, for example, in the center of the water tank 12 in the axial direction, or in the water tank end plate 122. Furthermore, a plurality of connection ports 17 may be provided. For example, when using a plurality of external water sources, such as tap water and bath water, a plurality of connection ports 17, water supply paths 18, and water supply valves 19 may be provided corresponding to them, in this case two of each.

[0018] Drainage path 20 shown in FIG. 2 is, for example, a flexible drainage hose, one end of which is connected to drainage valve 21, and the other end of which is drawn out of washing machine 10. Drainage valve 21 is, for example, an on-off valve for liquid that can be electromagnetically opened and closed. Drainage valve 21 is provided between drainage section 123 provided at the bottom of water tub 12 and drainage path 20, and opens and closes drainage path 20. Drainage section 123 is provided at the rear side, i.e., the lowest part, of the bottom of water tub 12. Drainage section 123, drainage path 20, and drainage valve 21 together constitute a drainage mechanism that discharges water stored in water tub 12 to the outside of washing machine 10.

[0019] Circulation path 22 is provided outside water tank 12. Circulation path 22 is a path that pumps up water stored in water tank 12 by circulation pump 23 and supplies the pumped water from the top of water tank 12 back into water tank 12. One end of circulation path 22 is connected to drainage section 123, and the other end is connected to nozzle section 221, which is a water discharge section provided on the top of water tank 12. Although details of nozzle section 221 are not shown, it is configured so that circulating water discharged from nozzle section 221 heads toward the center of water tank 12.

[0020] Circulation pump 23 is provided midway through circulation path 22. When circulation path 22 is driven with drainage path 20 closed by drainage valve 21, circulation pump 23 pumps up water in water tank 12 through drainage portion 123 and supplies the water again into water tank 12 from nozzle portion 221. In this way, circulation pump 23 circulates the water stored in water tank 12 through circulation path 22.

[0021] The operation panel 24 is provided on the front part of the top surface of the outer box 11 as shown in Fig. 1. Although not shown in detail, the operation panel 24 is provided with a power switch, a start key, various operation keys for the user to set operation courses, etc. The power switch may be provided separately from the operation panel 24. The user can operate the operation panel 24 to set whether or not to perform a pre-wash operation, the number of times Np the pre-wash process is to be performed, etc., which will be described in detail later.

[0022] 3, the control device 25 is mainly composed of a microcomputer having a CPU 251, a ROM, a RAM, and a storage area 252 such as a rewritable flash memory, and controls the overall operation of the washing machine 10. The control device 25 is electrically connected to the rotating tub motor 14, the first water supply valve 191, the second water supply valve 192, the drain valve 21, the circulation pump 23, the automatic feeding device 31 described later, and the like, and controls the operation of these components.

[0023] The treatment agent dosing mechanism 30 is provided on the upper part of the outer box 11, and is provided midway through the water supply path 18 or connected to the water supply path 18. The treatment agent dosing mechanism 30 has the function of introducing a laundry treatment agent into the water flowing through the water supply path 18, and supplying water containing the laundry treatment agent into the water tub 12 and the spin tub 13. The treatment agent dosing mechanism 30 is composed of an automatic dosing device 31 and a treatment agent case (not shown).

[0024] The automatic dosing device 31 can store the laundry treatment agent required for multiple washing operations inside in advance, and has the function of automatically dosing the required amount of laundry treatment agent into the water tub 12 as the washing operation progresses. The automatic dosing device 31 has a piston pump (not shown) that sucks up and discharges the laundry treatment agent from inside the automatic dosing device 31. The automatic dosing device 31 is provided connected to the water supply path 18, and under the control of the control device 25, the piston pump discharges and supplies the laundry treatment agent to the water supply path 18. Water supplied from an external water source is mixed with the laundry treatment agent supplied from the automatic dosing device 31 in the water supply path 18, and is supplied into the water tub 12.

[0025] A treatment agent case (not shown) is disposed midway through water supply path 18. The treatment agent case receives an amount of laundry treatment agent manually dispensed by the user for one operation, and supplies the laundry treatment agent to water tub 12 by passing the dispensed laundry treatment agent downstream together with the water flowing through water supply path 18. The treatment agent case also includes a detergent dispenser that receives detergent dispensed as a laundry treatment agent, and a fabric softener dispenser that receives fabric softener dispensed. The detergent dispenser and fabric softener dispenser constitute parts of first water supply path 181 and second water supply path 182, respectively.

[0026] When executing a washing operation, the user can select whether to automatically dispense laundry treatment agent using the automatic dispenser 31 or to manually dispense one load of laundry treatment agent using the operation panel 24. In this embodiment, the laundry treatment agent is a concept that includes liquid or powder detergent, fabric softener, and fragrance, but is not limited to these as long as it is an agent that can be used in a washing operation.

[0027] The control device 25 can execute, as operation courses, for example, a washing operation, a drying operation, and a washing and drying operation for executing the washing operation and the drying operation. The washing operation includes a washing step, a rinsing step, and a spin-drying step, as shown in FIG. 4. The washing step is a step of cleaning the laundry using a laundry treatment agent, for example, a detergent. The rinsing step is a step of rinsing the laundry after the washing step to remove the laundry treatment agent, such as the detergent, from the laundry. In the rinsing step, the washing machine 10 may treat the laundry with water containing a laundry treatment agent, such as a fabric softener. The spin-drying step is a step of removing moisture from the laundry after the rinsing step.

[0028] First, the operation of each component in the washing process will be described. The control device 25 can select and execute the washing process alternatively from a course with pre-wash including a pre-wash process and a main wash process, and a course without pre-wash including a main wash process but not including a pre-wash process. The pre-wash process is a process executed in a period before the main wash process in the course with pre-wash. In the pre-wash process, the washing machine 10 washes laundry before the main wash process to remove heavy dirt from the laundry. In the course with pre-wash, the main wash process is a process executed after the pre-wash process, and in the course without pre-wash, it is a process executed after the start of the washing process. In the main wash process, the washing machine 10 washes laundry with a normal level of dirt or laundry with a lesser degree of dirt after the pre-wash process.

[0029] In the course with pre-wash, the washing process is performed including one or more pre-wash processes, multiple intermediate spin-dry processes, a main wash process, and a foam removal process. FIG. 5 shows an example of a course with pre-wash including multiple pre-wash processes. The number of times Np to perform the pre-wash process may be set by the user or the control device 25 may set the number of times Np. When the number of times Np is set by the user, the user can set the number of times Np to perform the pre-wash process by, for example, inputting operation to the operation panel 24. When the control device 25 automatically sets the number of times Np, the following can be done. For example, a dirt sensor and a weight sensor may be provided in the washing machine 10, and the control device 25 may set the number of times Np to perform the pre-wash process based on a chart or the like preset in the memory area 252 according to the degree of dirt detected by the dirt sensor and the weight of the laundry detected by the weight sensor.

[0030] As a pre-wash process, the control device 25 puts a laundry treatment agent into the water tub 12, opens the first water supply valve 191 to supply water to the water tub 12, and drives the rotary tub motor 14 to wash the laundry with the water containing the laundry treatment agent. In the pre-wash process, the control device 25 also drives the circulation pump 23 to circulate the water containing the laundry treatment agent, and agitates the laundry, the laundry treatment agent, and the water. At the end of the pre-wash process, the control device 25 opens the drain valve 21 to drain the water in the water tub 12 outside the machine.

[0031] In the main wash process, the control device 25 puts the laundry treatment agent into the water tub 12, opens the first water supply valve 191 to supply water to the water tub 12, and drives the rotary tub motor 14 to wash the laundry with the water containing the laundry treatment agent. In addition, in the main wash process, the control device 25 drives the circulation pump 23 for a certain period of time to circulate the water containing the laundry treatment agent and agitate the laundry, the laundry treatment agent, and the water. At the end of the main wash process, the control device 25 opens the drain valve 21 to drain the water in the water tub 12 outside the machine.

[0032] The intermediate spin-drying process is a process in which the water contained in the laundry is separated by centrifugal force after a rinsing process other than the pre-washing process, the main washing process, or the final rinsing process, and discharged outside the machine. The control device 25 drives the spin tub motor 14 with the drain valve 21 open.

[0033] The foam removal process is a process that is performed after the main washing process and before the intermediate spin-drying process. The foam removal process is a process that discharges foam remaining in the water tub 12 and / or the rotating tub 13 after draining to the outside of the machine. In the foam removal process, the control device 25 drives the rotating tub motor 14 with the drain valve 21 open to intermittently open the first water supply valve 191. That is, in the foam removal process, the control device 25 repeatedly opens the first water supply valve 191 for a predetermined period and closes it for a predetermined period. When the first water supply valve 191 is open, water from the outside is supplied from the water inlet 124 to the water tub 12 and the rotating tub 13. Foam remaining in the machine that was attached to the water tub 12 and the rotating tub 13 or the inside of the door 15 is washed away by the water and discharged from the drain section 123 through the drain path 20 to the outside of the machine. Since the range that the water injected from the water inlet 124 reaches is constant, there is a risk that water will continue to be injected into a place where foam has already been washed away even if water supply is continued as is. For this reason, the water supply is stopped for a predetermined period of time to allow time for the rotation of the rotating tub 13 by the rotating tub motor 14 and for the foam to move by its own weight. After the water supply is stopped for the predetermined period of time, the control device 25 opens the first water supply valve 191 again to supply water from the water inlet 124 toward the water tub 12 and the rotating tub 13 or toward the inside of the door 15.

[0034] The specific operation of each component in the pre-wash process and the main wash process will be described below. The execution period of the pre-wash process includes an input period Tpa, a water supply period Tpb, a washing period Tpc, and a drainage period Tpd, as shown in Fig. 6. The execution period of the main wash process includes an input period Tma, a water supply period Tmb, a washing period Tmc, and a drainage period Tmd, as shown in Fig. 7.

[0035] The supplying period Tpa and the supplying period Tma are periods during which laundry treatment agents such as detergent used in the washing process are supplied to the water supply path 18. The water supplying period Tpb and the water supplying period Tmb are periods during which the first water supply valve 191 is opened to supply water to the water tub 12 with the drain valve 21 closed. The washing period Tpc and the washing period Tmc are periods during which the rotary tub motor 14 is driven to rotate the rotary tub 13 with the drain valve 21 closed, and the circulation pump 23 is driven to circulate the water in the water tub 12. The draining period Tpd and the draining period Tmd are periods during which the drain valve 21 is opened to discharge the water stored in the water tub 12 to the outside of the machine.

[0036] 6 and 7 show the operation of each component when performing a pre-wash process or a main wash process using the automatic insertion device 31. In the drawings, ON indicates that each component is driven or operated, and OFF indicates that each component is stopped.

[0037] When automatic loading is performed, in the loading period Tpa and the loading period Tma, the control device 25 drives the automatic loading device 31 to execute a loading process of loading a predetermined amount of laundry treatment agent into the first water supply path 181. When the user manually loads the laundry treatment agent for one pre-wash process into the treatment agent case, the control device 25 may, for example, display a guide to the predetermined loading amount on the operation panel 24 to prompt the user to load the laundry treatment agent. When the user manually loads the laundry treatment agent for one pre-wash process into the treatment agent case, the following can be done. For example, the washing machine 10 may be configured to hold the laundry treatment agent loaded into the treatment agent case by the user during the periods before the loading period Tpa and the loading period Tma, respectively, in the treatment agent case or the first water supply path 181 until the start of the subsequent water supply periods Tpb and Tmb, respectively.

[0038] During the loading period Tpa, the controller 25 closes the first water supply valve 191 and the drain valve 21. The controller 25 also stops the circulation pump 23 and the rotating tub motor 14. In the washing process, the controller 25 does not drive the automatic loading device 31 during any period other than the loading period Tpa. In addition, throughout the entire washing process, the controller 25 closes the second water supply valve 192.

[0039] During the water supply period Tpb and the water supply period Tmb, the controller 25 executes a water supply process in which the drain valve 21 is closed and the first water supply valve 191 is opened. Therefore, water from an external water source is supplied to the water tub 12 through the water supply path 18. The controller 25 keeps the first water supply valve 191 open until the amount of water stored in the water tub 12 reaches a water amount that is preset according to the weight of the laundry, the degree of dirt, and the like. Furthermore, during the water supply period Tpb, the controller 25 drives the spin tub motor 14 to rotate the spin tub 13. This allows the laundry in the spin tub 13 to be evenly permeated with water. During the water supply period Tpb and the water supply period Tmb, the controller 25 keeps the drain valve 21 closed and the circulation pump 23 stopped.

[0040] During the water supply period Tpb and the water supply period Tmb, the control device 25 rotates the rotating tub motor 14 forward and reverse at a first rotation speed x1 in a predetermined cycle. The first rotation speed x1 can be set within a range of 40 to 50 rpm, for example. In this embodiment, the first rotation speed x1 is set to 45 rpm. The cycle of forward and reverse rotation can be set so that forward and reverse rotation are repeated every 10 seconds, for example.

[0041] During the washing periods Tpc and Tmc, the controller 25 executes a washing process by driving the circulation pump 23 with the drain valve 21 closed. This causes the water containing the laundry treatment agent in the water tub 12 to circulate through the circulation path 22 and be supplied back into the water tub 12. The controller 25 also drives the rotatable tub motor 14 to rotate the rotatable tub 13. This causes the water, the laundry treatment agent, and the laundry to be agitated by the circulation of the water and the rotation of the rotatable tub 13, and effectively separates dirt from the laundry and moves it into the water. During the washing periods Tpc and Tmc, the controller 25 closes the first water supply valve 191 and the drain valve 21.

[0042] During the washing periods Tpc and Tmc, the control device 25 rotates the rotation tub motor 14 forward and reverse at a predetermined cycle at the first rotation speed x1. The cycle of forward and reverse rotation during the washing periods Tpc and Tmc can be set so that forward and reverse rotation are repeated every 20 seconds, for example.

[0043] During the washing period Tpc and the washing period Tmc, the control device 25 drives the circulation pump 23 at a first drive frequency y1. The first drive frequency y1 can be set in the range of, for example, 3000 to 3500 rpm. In this embodiment, the first drive frequency y1 is set to 3350 rpm. The first drive frequency y1 is a frequency equal to or higher than a drive frequency required for the circulation pump 23 to lift the water at the bottom of the water tub 12 to the top of the water tub 12. When the circulation pump 23 is driven at the first drive frequency y1, the water discharged from the nozzle portion 221 is discharged with force toward the region from the axial center of the rotating tub 13 to the rotating tub end plate 132.

[0044] The control device 25 drives the circulation pump 23 for a period of 3 / 4 or more of the washing period Tpc in the pre-washing process. In this embodiment, the control device 25 drives the circulation pump 23 over the entire washing period Tpc. Therefore, in this embodiment, the circulation period Tpe during which the circulation pump 23 is driven in the pre-washing process is equal to the washing period Tpc. The length of the washing period Tpc in the pre-washing process can be set, for example, in the range of 5 to 6 minutes. In this embodiment, the length of the washing period Tpc in the pre-washing process is set to 5.5 minutes. Therefore, in this embodiment, the length of the circulation period Tpe in the pre-washing process is set to 5.5 minutes.

[0045] The control device 25 drives the circulation pump 23 during a part of the washing period Tmc in the main washing process, and stops the circulation pump 23 during the remaining period. The circulation period Tme, which is the driving period of the circulation pump 23 in the main washing process, is the period in the early stage of the washing period Tmc. That is, the control device 25 drives the circulation pump 23 during the early stage of the washing period Tmc. As a result, the control device 25 circulates the water containing the laundry treatment agent to agitate it and further dissolve the laundry treatment agent during the early stage of the washing process. For example, in this embodiment, the circulation period Tme starts at the same time as the start of the washing period Tmc. Moreover, the control device 25 stops the circulation pump 23 during the later stage of the washing period Tmc, which is the period after the circulation period Tme. As a result, after the laundry treatment agent is sufficiently dissolved, the water containing the laundry treatment agent is not circulated, thereby suppressing excessive foaming of the water in the water tub 12.

[0046] For example, the control device 25 drives the circulation pump 23 for a period equal to or less than 1 / 2 the total length of the washing period Tmc in the main washing process. In this embodiment, the control device 25 drives the circulation pump 23 for a period equal to 1 / 2 the total length Tmc of the washing period. The length of the washing period Tmc in the main washing process can be set, for example, in the range of 5.5 to 6.5 minutes. In this embodiment, the length of the washing period Tmc in the main washing process is set to 6 minutes. Therefore, in this embodiment, the length of the circulation period Tme in the main washing process is set to 3 minutes. In order to suppress excessive foaming, the length of the circulation period Tme in the main washing process is set to be shorter than the length of the circulation period Tpe in the pre-washing process.

[0047] During the drainage periods Tpd and Tmd, the controller 25 opens the drainage valve 21 to execute a drainage process to drain the water in the water tub 12. As a result, the water in the water tub 12 is discharged outside the apparatus through the drainage path 20. Also, during the drainage period Tpd, the controller 25 drives the rotating tub motor 14 to rotate the rotating tub 13. During the drainage periods Tpd and Tmd, the controller 25 closes the first water supply valve 191 and stops driving the circulation pump 23.

[0048] During the drainage period Tpd and the drainage period Tmd, the controller 25 rotates the rotatable tub motor 14 forward and reverse at the second rotation speed x2 in a predetermined cycle. The second rotation speed x2 is equal to or greater than the first rotation speed x1, and is a rotation speed at which the laundry sticks to the inner wall of the rotatable tub 13 due to centrifugal force. This causes the laundry to stick to the inner wall of the rotatable tub 13, facilitating drainage of water from the laundry. The second rotation speed x2 can be set within a range of 45 to 55 rpm, for example. The cycle of forward and reverse rotation during the drainage period Tpd can be set so that forward and reverse rotations are repeated every 20 seconds, for example.

[0049] The length of the drainage period Tpd in the pre-wash process is set to be equal to or longer than the period required to drain the maximum amount of water stored in the water tub 12 to the outside of the machine. The length of the drainage period Tpd can be set within the range of 1 to 2 minutes, for example. In this embodiment, the length of the drainage period Tpd is set to 1.5 minutes.

[0050] The length of the drainage period Tmd in the main washing process is set to be longer than the period required to drain the maximum amount of water stored in the water tub 12 to the outside of the machine. Furthermore, the length of the drainage period Tmd in the main washing process is set to be longer than the drainage period Tpd in the pre-washing process. Specifically, the length of the drainage period Tmd is set to be longer than the length of the drainage period Tpd plus the standby period Tmf. The standby period Tmf is a period for removing bubbles generated in the water tub 12 or for the bubbles to disappear naturally. The length of the standby period Tmf can be set to be approximately the same as the length of the drainage period Tpd, for example, within the range of 1 to 2 minutes. In this embodiment, the length of the standby period Tmf is set to 1.5 minutes.

[0051] As shown in Fig. 6, the controller 25 executes an intermediate spin-drying process following the pre-washing process. Also, as shown in Fig. 7, the controller 25 executes an intermediate spin-drying process after the main-washing process and the foam-removing process. In the intermediate spin-drying process, the controller 25 rotates the spin-tub 13 by driving the spin-tub motor 14 with the drain valve 21 open. This centrifugally separates the water contained in the laundry, and the water containing dirt is discharged outside the machine.

[0052] In the intermediate spin-drying process, the control device 25 rotates the rotatable tub motor 14 forward and reverse at the third rotation speed x3 in a predetermined cycle. In this case, the third rotation speed x3 is a target rotation speed, and the control device 25 gradually increases the rotation speed from 0 rpm to the third rotation speed x3, which is the target rotation speed. The third rotation speed x3 is a rotation speed higher than the first rotation speed x1 and the second rotation speed x2. The third rotation speed x3 can be set, for example, within a range of 750 to 1500 rpm. The cycle of forward and reverse rotation in the intermediate spin-drying process can be set so that forward and reverse rotation are repeated every 90 seconds, for example. The execution period of the intermediate spin-drying process can be set by the control device 25 according to the weight and / or fabric quality of the laundry in the washing tub, or according to an input operation by the user to the operation panel 24.

[0053] As shown in FIG. 7, the control device 25 executes a foam removal process following the main wash process and before the intermediate spin-dry process. In the foam removal process, the control device 25 opens the first water supply valve 191 to supply water to the water tub 12. As a result, water from an external water source that does not contain a laundry treatment agent is supplied to the water tub 12 from the water inlet 124. A part of the water supplied into the water tub 12 from the water inlet 124 flows inside the door 15. At this time, this water washes away foam remaining on the opening 131 side of the spin tub 13 and foam attached to the door 15. In addition, the control device 25 drives the spin tub motor 14 at the second rotation speed x2 in the foam removal process to rotate the spin tub 13. As a result, the laundry is stuck to the inner wall of the spin tub 13, which again promotes drainage from the laundry and promotes movement of the foam.

[0054] In the bubble removal process, it is possible to continuously open the first water supply valve 191, but in that case, the water in the water tank 12 may be agitated by the water that is poured in, which may cause bubbles to form. In addition, since the water poured from the water inlet 124 is basically discharged toward a certain range, even if water is continuously supplied, the water only reaches a certain part of the door 15, and bubbles attached to the inside of the door 15 in particular cannot be effectively removed. Furthermore, if water is continuously flowed only toward a certain range, the water that hits the inside of the door 15 may push the bubbles apart in a direction away from the drainage section 123 due to the water pressure.

[0055] Therefore, in the foam removal process, as shown in Fig. 8, controller 25 intermittently opens first water supply valve 191 to intermittently supply water to water tub 12. As a result, washing machine 10 shortens the period during which water is supplied in the foam removal process, and suppresses excessive foaming. The period during which water supply is stopped is a waiting period, so to speak, during which foam remaining in spin tub 13 and foam attached to door 15, etc., are waited for to move with the water by their own weight, and foam in spin tub 13 is waited for to move with the rotation of spin tub 13.

[0056] The execution period of the foam removing process is set to be longer than the length of the drainage period Tpd in the pre-washing process. For example, the execution period of the foam removing process can be set within the range of 1.5 to 2.5 minutes. In this embodiment, the execution period of the foam removing process is set to 1.8 minutes.

[0057] In the bubble removal process, the number of times the first water supply valve 191 is opened and closed is defined as nmax times, the length of the period during which the first water supply valve 191 is opened the first time is defined as Ti1, the length of the period during which the first water supply valve 191 is opened the nth time is defined as Tin, and the length of the period during which the first water supply valve 191 is opened the final time, i.e., the nmaxth time, is defined as Tinmax. Furthermore, the length of the period during which the first water supply valve 191 is opened and then closed the first time is defined as Tj1, the length of the period during which the first water supply valve 191 is opened and then closed the nth time is defined as Tjn, and the length of the period during which the first water supply valve 191 is opened and then closed the nmaxth time is defined as Tjnmax.

[0058] In this embodiment, the length Tin of the period during which the first water supply valve 191 is opened and the length Tjn of the period during which the first water supply valve 191 is closed are each set to be constant throughout the entire bubble removal process. In other words, the length Ti1 of the period during which the first water supply valve 191 is opened the first time and the length Tinmax of the period during which the first water supply valve 191 is opened the nmax time are set to be the same. Also, the length Tj1 of the period during which the first water supply valve 191 is closed the first time and the length Tjnmax of the period during which the first water supply valve 191 is closed the nmax time are set to be the same.

[0059] Furthermore, the length Tj1 of the period during which the first water supply valve 191 is closed the first time is set longer than the length Ti1 of the period during which the first water supply valve 191 is opened the first time. Also, in this embodiment, the length Tjn of the period during which the first water supply valve 191 is closed the nth time is set longer than the length Tin of the period during which the first water supply valve 191 is opened the nth time. Therefore, throughout the entire bubble removal process, the total period during which the first water supply valve 191 is closed is set longer than the total period during which the first water supply valve 191 is opened. This shortens the water supply period, suppresses re-foaming in the bubble removal process, and reduces the amount of water used.

[0060] FIG. 9 shows the length Tin of the period during which the first water supply valve 191 is opened and the length Tjn of the period during which the first water supply valve 191 is closed at each count n of the number of repetitions of opening and closing the first water supply valve 191 when the number of repetitions nmax is 4. The period Tin during which the first water supply valve 191 is opened can be set within a range of, for example, 10 to 15 seconds. In this embodiment, the period Tin during which the first water supply valve 191 is opened is set to 12 seconds. Also, the period Tjn during which the first water supply valve 191 is closed can be set within a range of, for example, 10 to 20 seconds. In this embodiment, the period Tjn during which the first water supply valve 191 is opened is set to 15 seconds. Also, the period Tin during which the first water supply valve 191 is closed is set to 12 seconds.

[0061] Next, the operation of each component in the rinsing process will be described. As shown in FIG. 10, the rinsing process includes 0, 1, or multiple rinsing processes, 0, 1, or multiple intermediate spin-drying processes, and a final rinsing process. In other words, the rinsing process may be configured not to include the rinsing process and the intermediate spin-drying process, that is, to perform only the final rinsing process as the rinsing process. The rinsing process is a process performed in advance before the final rinsing process, and is a process for removing the laundry treatment agent used in the washing process from the laundry. The intermediate spin-drying process performed after the rinsing process in the rinsing process is similar to the intermediate spin-drying process in the washing process. The final rinsing process is a process performed at the final stage of the rinsing process before the subsequent spin-drying process. The final rinsing process is a process for further removing the laundry treatment agent used in the washing process from the laundry, and in some cases treating the laundry with a laundry treatment agent such as a fabric softener.

[0062] The number of times Nr the rinsing process and the intermediate spin-drying process are performed in the rinsing step may be set by the user or may be set by the control device 25. When the number of times Nr is set by the user, the user can set the number of times Nr the rinsing process is performed by, for example, inputting information into the operation panel 24. When the control device 25 automatically sets the number of times Nr the rinsing process is performed, the following can be done. For example, a residual detergent sensor and a weight sensor may be provided in the washing machine 10, and the control device 25 may set the number of times Nr the rinsing process is performed based on a chart or the like preset in the memory area 252 according to the level of remaining detergent detected by the residual detergent sensor and the weight of the laundry detected by the weight sensor.

[0063] In the rinsing process, the control device 25 opens the first water supply valve 191 to supply water, drives the spin tub motor 14 to rotate the spin tub 13, and drives the circulation pump 23 to circulate the water in the water tub 12. This agitates the laundry and the water in the water tub 12, and the laundry treatment agents such as detergent contained in the laundry are extracted into the water in the water tub 12. In the final rinsing process, the control device 25 opens the first water supply valve 191 and the second water supply valve 192 to supply water, drives the spin tub motor 14 to rotate the spin tub 13, and drives the circulation pump 23 to circulate the water in the water tub 12. In addition, when a laundry treatment agent such as fabric softener is added using the automatic addition device 31, the control device 25 drives the automatic addition device 31 in the final rinsing process. As a result, laundry treatment agents such as fabric softener stored in automatic dispenser 31 are sucked into second water supply path 182, dissolved in the water passing through second water supply path 182, and supplied to water tub 12.

[0064] Next, specific operations of each component in the final rinsing process will be described with reference to Fig. 11. Fig. 11 shows the operations of each component when the final rinsing process is performed using the automatic dispenser 31. The execution period of the final rinsing process includes a dispense period Tra, a water supply period Trb, a rinsing period Trc, and a drain period Trd.

[0065] The supply period Tra is a period during which a laundry treatment agent used in the rinsing step, such as a fabric softener, is supplied to the second water supply path 182. In this case, the laundry treatment agent may be automatically supplied to the second water supply path 182 by the automatic supply device 31, or the user may manually supply the laundry treatment agent to the fabric softener supply section of the treatment agent case. The water supply period Trb is a period during which the water supply valve 19 is opened with the drain valve 21 closed and water is supplied from an external water source to the water tub 12 via the water supply path 18. The water supply period Trb is a period after the supply period Tra, and is also a period during which the laundry treatment agent supplied to the second water supply path 182 is supplied to the water tub 12. The rinsing period Trc is a period after the water supply period Trb, and is a period during which the rotatable tub motor 14 is driven with the drain valve 21 closed to rotate the rotatable tub 13 and the circulation pump 23 is driven to circulate the water in the water tub 12, thereby rinsing laundry with water that may or may not contain a laundry treatment agent. The drain period Trd is a period following the rinsing period Trc, during which the drain valve 21 is opened to drain the water stored in the water tub 12 to the outside of the machine.

[0066] When automatic dispensing is performed, during the dispensing period Tra, the control device 25 drives the automatic dispensing device 31 to dispense laundry treatment agents such as fabric softener into the second water supply path 182. The control device 25 closes the first water supply valve 191, the second water supply valve 192, and the drain valve 21, and stops the circulation pump 23 and the rotary tub motor 14. Note that the control device 25 does not drive the automatic dispensing device 31 during the rinsing process except during the dispensing period Tra.

[0067] During the supply period Tra, the control device 25 drives the automatic supply device 31 to supply a predetermined amount of laundry treatment agent to the second water supply path 182. When the user manually supplies the laundry treatment agent for one rinsing step to the treatment agent case, the control device 25 may prompt the user to supply the laundry treatment agent during a period before the supply period Tra, such as at the start of a washing operation. In this case, the control device 25 may display, for example, a guide to the predetermined supply amount on the operation panel 24. When the user manually supplies the laundry treatment agent for one rinsing step to the treatment agent case, the washing machine 10 may be configured to hold the laundry treatment agent that was supplied to the treatment agent case by the user during the period before the supply period Tra in the treatment agent case or the second water supply path 182 until the start of the subsequent water supply period Trb.

[0068] In the water supply period Trb, the control device 25 first executes a process of opening the second water supply valve 192 with the drain valve 21 closed. Therefore, water from an external water source is supplied to the water tub 12 via the second water supply path 182, and the laundry treatment agent put into the second water supply path 182 is dissolved in the water from the external water source and supplied to the water tub 12. The control device 25 closes the second water supply valve 192 and opens the first water supply valve 191 at a time point P1 during the water supply period Trb shown in FIG. 11. The time point P may be any time point after the laundry treatment agent put into the second water supply path 182 is supplied to the water tub 12. For example, the control device 25 can determine that the time point P has been reached when a predetermined period has elapsed after the start of the water supply period Trb or when the amount of water stored in the water tub 12 detected by a water amount sensor (not shown) has reached a predetermined amount of water, and close the second water supply valve 192 and open the first water supply valve 191.

[0069] Next, the controller 25 keeps the first water supply valve 191 open until the amount of water stored in the water tub 12 reaches a predetermined amount of water that is preset according to the weight of the laundry, the degree of dirt, etc. During the water supply period Trb, the controller 25 drives the rotatable tub motor 14 to rotate the rotatable tub 13. This allows the water containing or not containing the laundry treatment agent to permeate evenly into the laundry in the rotatable tub 13. During the water supply period Trb, the controller 25 keeps the drain valve 21 closed and stops the circulation pump 23.

[0070] During the water supply period Trb and the subsequent rinsing period Trc, the control device 25 intermittently rotates the rotating tub motor 14 forward and reverse at a third rotation speed x3 in a predetermined cycle. The third rotation speed x3 can be set within a range of 20 to 30 rpm, for example. In this embodiment, the third rotation speed x3 is set to 25 rpm. In this case, the cycle of the intermittent forward and reverse rotation can be set so that the motor rotates forward for 4 seconds, stops for 1.5 seconds, rotates reversely for 4 seconds, and stops for 1.5 seconds.

[0071] During the rinsing period Trc, the controller 25 drives the rotatable tub motor 14 to rotate the rotatable tub 13 with the drain valve 21 closed. This causes the water and the laundry to be agitated by the circulation of water and the rotation of the rotatable tub 13, effectively removing laundry treatment agents such as detergent from the laundry and treating the laundry with laundry treatment agents such as fabric softener. During the rinsing period Trc, the controller 25 closes the first water supply valve 191, the second water supply valve 192, and the drain valve 21.

[0072] In addition, in the rinsing period Trc, the control device 25 drives the circulation pump 23. In this case, the rinsing period Trc includes a circulation stop period Tre, a high frequency period Trf, and a low frequency period Trg. The circulation stop period Tre is a period after the start of the rinsing period Trc, during which the circulation pump 23 is stopped. The high frequency period Trf is a period after the circulation stop period Tre, during which the circulation pump 23 is driven at a drive frequency higher than the drive frequency in the low frequency period Trg. The low frequency period Trg is a period after the high frequency period Trf, during which the circulation pump 23 is driven at a drive frequency lower than the drive frequency in the high frequency period Trf.

[0073] During the circulation stop period Tre, the control device 25 stops driving the circulation pump 23. During the high frequency period Trf, the control device 25 executes a high frequency driving process in which the circulation pump 23 is driven at a frequency equal to or higher than a driving frequency that outputs hydraulic power required to lift the water at the bottom of the water tank 12 to the top of the water tank 12. During the high frequency driving process, the control device 25 drives the circulation pump 23 at a second driving frequency y2. The second driving frequency y2 is equal to or higher than a driving frequency that outputs hydraulic power required to lift the water at the bottom of the water tank 12 to the top of the water tank 12. When the circulation pump 23 is driven at the second driving frequency y2, the water discharged from the nozzle portion 221 is discharged vigorously toward the region from the axial center of the rotating tank 13 to the rotating tank end plate 132, as shown by the hatched area in FIG. 12, for example. The second driving frequency y2 can be set, for example, in the range of 3000 to 3500 rpm. In this embodiment, the second drive frequency y2 is set to 3350 rpm, similar to the first drive frequency y1.

[0074] In the low frequency period Trg, the control device 25 executes a low frequency drive process in which the circulation pump 23 is driven at a frequency lower than the drive frequency at which the hydraulic power required to lift the water at the bottom of the water tank 12 to the top of the water tank 12 is output. In the low frequency drive process, the control device 25 drives the circulation pump 23 at a third drive frequency y3. The third drive frequency y3 is set lower than the first drive frequency y1 and the second drive frequency y2. The third drive frequency y3 is a drive frequency at which the water pushed up the circulation path 22 by the circulation pump 23 loses momentum as it is discharged backward from the nozzle portion 221 and flows downward due to gravity. The third drive frequency y3 is a drive frequency at which the circulation pump 23 outputs hydraulic power required to lift the water at the bottom of the water tank 12 to the top of the water tank 12, but when the circulation path 22 is already filled with circulating water, the circulation pump 23 outputs hydraulic power that enables the circulation to continue.

[0075] 13, the water discharged from the nozzle portion 221 flows down toward the opening 131 side, i.e., the area closer to the door 15 than the center of the rotating tub 13. Therefore, in the low frequency period Trg, the water circulating through the circulation path 22 flows down the inside of the door 15 and washes away the foam adhering to the door 15. The third drive frequency y3 can be set, for example, in the range of 1000 to 2000 rpm. In this embodiment, the third drive frequency y3 is set to 1530 rpm.

[0076] In this case, the water flowing through the circulation path 22 from the beginning may be directed toward the area closer to the door 15, but if the circulation path 22 is driven at the third drive frequency y3 from the beginning, it will not be possible to obtain sufficient hydraulic power to lift the water discharged from the bottom of the water tub 12 to the top of the water tub 12. Therefore, the control device 25 drives the circulation pump 23 at the second drive frequency y2 during the high frequency period Trf to fill the circulation path 22 with water, and then drives the circulation pump 23 at the third drive frequency y3.

[0077] The length of the high-frequency period Trf is set to be equal to or longer than the period required to fill the circulation path 22 with water, that is, to lift the water at the bottom of the water tank 12 up to the nozzle portion 221. The length of the high-frequency period Trf can be set within a range of, for example, 3 to 10 seconds. In this embodiment, the length of the high-frequency period Trf is set to 5 seconds. The length of the low-frequency period Trg is set to be longer than the length of the high-frequency period Trf. For example, the length of the low-frequency period Trg can be set within a range of 10 to 20 seconds. In this embodiment, the length of the low-frequency period Trg is set to 10 seconds.

[0078] The combined length of the input period Tra, the water supply period Trb, and the rinsing period Trc can be set within a range of, for example, 0.75 to 1.5 minutes. In this embodiment, the combined length of the input period Tra, the water supply period Trb, and the rinsing period Trc is set to 1 minute.

[0079] During the drainage period Trd, the control device 25 opens the drainage valve 21 to drain the water in the water tank 12 to the outside of the machine. In this case, the control device 25 drives the circulation pump 23 from the start of the drainage period Trd until time P2 during the drainage period. In this case, the drive frequency of the circulation pump 23 is set to the third drive frequency y3. Therefore, even after the start of the drainage process, water flows down from the nozzle portion 221 toward the inside of the door 15 until time P2, washing away the foam on the inside of the door 15.

[0080] Time point P2 is the time point when the water level in the water tank 12 reaches a predetermined water level. The predetermined water level is the lowest water level that the circulation pump 23 can pump. In other words, the water level is a water level below which the circulation pump 23 cannot circulate the water in the water tank 12 through the circulation path 22. In this embodiment, the control device 25 determines that time point P2 has been reached when, for example, a water level sensor (not shown) detects that the water level has fallen below the predetermined water level, but this is not limited to this. In another embodiment, the control device 25 may be configured to determine that time point P2 has been reached, i.e., that the water level has fallen below the predetermined water level, when the elapsed time since the drain valve 21 was opened, i.e., the elapsed time since the start of the drainage process, has passed a preset period.

[0081] When time P2 is reached, the control device 25 stops driving the circulation pump 23 and opens the first water supply valve 191. This causes water from the external water source to be supplied again into the water tub 12 before the spin-drying process. The length of the final water supply period Trh, which is the period during which the first water supply valve 191 is opened after time P has elapsed, can be set within a range of 5 to 15 seconds, for example. In this embodiment, the length of the final water supply period Trh is set to 10 seconds. After the final water supply period Trh has elapsed, the control device 25 closes the first water supply valve 191.

[0082] The length of the drainage period Trd is set to a period from the completion of drainage from the water tank 12 until a predetermined period has elapsed. In this embodiment, the predetermined period is set to 10 seconds. In addition, the control device 25 determines that drainage from the water tank 12 is completed when the water level detected by the water level sensor is equal to or lower than the bottom end of the water tank 12.

[0083] When the drain period Trd has elapsed, the control device 25 ends the rinsing step. After the rinsing step is completed, the control device 25 executes the spin-drying step. The spin-drying step can be executed according to any known method.

[0084] Here, when the pre-wash process and the main wash process are performed, the amount of laundry treatment agent such as detergent used is relatively large relative to the dirt on the laundry, and there is a risk of a large amount of foam being generated. Therefore, there is a possibility that foam may remain inside the spin tub 12 or inside the door 15 even after the rinsing and spin-drying processes. In that case, the finish of the laundry may deteriorate, or a user who sees the foam may have doubts about the finish of the laundry even if there is no problem with the finish of the laundry itself.

[0085] In contrast, according to the present embodiment described above, washing machine 10, which is a laundry processing device, includes outer case 11, water tub 12, water supply paths 181 and 182, water supply valves 191 and 192, drain path 20, drain valve 21, and control device 25. Water tub 12 is provided inside outer case 11. Water supply paths 181 and 182 have a function of supplying water supplied from an external water source to water tub 12. Water supply valves 191 and 192 open and close water supply paths 181 and 182. Drain path 20 has a function of draining water from water tub 12. Drain valve 21 opens and closes drain path 20. Control device 25 is configured to be able to execute a washing operation including a washing process, a rinsing process, and a spin-drying process by controlling the opening and closing of water supply valves 191 and 192 and the opening and closing of drain valve 21. In the washing process, the control device 25 can execute a pre-wash process and a main wash process which is executed after the pre-wash process, and executes a defoaming process by opening the water supply valves 191, 192 to supply water while keeping the drain valve 21 open.

[0086] According to this, the washing machine 10 executes the foam removal process when the washing process is a pre-wash course including a pre-wash process and a main wash process, so that even if a large amount of foam is generated, the amount of foam remaining in the spin tub 13 can be reduced. This improves the finish of the laundry and also improves the user's satisfaction with the finish of the laundry.

[0087] Here, if a large amount of foam is generated during the washing process, even if the water in the water tub 12 is discharged outside the machine by performing a drainage process, there is a risk that the foam will not flow away with the water and will remain inside the water tub 12 or the rotating tub 13.

[0088] In contrast, the main washing process includes a draining process in which the drain valve 21 is opened to drain the water from the water tub 12. The control device 25 executes the defoaming process after the draining process. That is, the control device 25 executes the defoaming process after the main washing process and before the rinsing step.

[0089] According to this, the foam remaining in water tub 12 and spin tub 13 even after the drainage process can be reduced by the foam removal process. This improves the finish of the laundry and also improves the user's satisfaction with the finish of the laundry.

[0090] In this embodiment, the foam removal process is performed after the drainage process is completed, i.e., after the drainage period has elapsed, but this is not limited to the above. In other words, "performing the foam removal process after the drainage process is completed" does not only mean performing the foam removal process after the drainage process is completed, i.e., after the drainage period has elapsed, but also includes performing the foam removal process after the drainage process has started and before the drainage process is completed, i.e., before the drainage period has elapsed. For example, the foam removal process may be performed when the water in the water tub 12 has been drained to such an extent that excessive foaming does not occur even if the rotating tub motor 14 is driven after the drainage process has started.

[0091] Here, the washing machine 10 equipped with the automatic dispenser 31 can automatically dispense a predetermined amount of laundry treatment agent in each of the pre-wash process and the main wash process. However, in the case of automatic dispense, even if a weight sensor, fabric sensor, dirt sensor, etc. are installed, it is difficult to perfectly grasp the weight, fabric quality, and dirtiness of the laundry and set the appropriate amount of detergent precisely. Therefore, when detergent is automatically dispensed, the predetermined amount may generally be set to be larger. Therefore, for example, when the laundry is not very dirty or the dirt can be relatively easily removed, there is a risk that a large amount of foam will be generated especially in the main operation.

[0092] In response to this, the washing machine 10 is provided with an automatic dispenser 31 that automatically dispenses the laundry treatment agent into the water tub 12. The pre-wash process or the main wash process is performed including a dispenser process that drives the automatic dispenser 31 to dispense the laundry treatment agent.

[0093] According to this, even if the washing machine 10 automatically dispenses a laundry treatment agent, the generated foam can be reduced by the foam removal process, so that the finish of the laundry can be improved.

[0094] Here, since water can only be discharged from water inlet 124 to a certain range, the area in rotating tub 13, particularly the inside of door 15, that the water discharged from water inlet 124 comes into contact with is fixed. Therefore, bubbles can only be removed from a part of rotating tub 13 or the inside of door 15 by simply supplying water.

[0095] In response to this, the control device 25 executes water supply during the bubble removal process by intermittently opening and closing the water supply valves 191 and 192. In other words, the control device 25 executes the opening and closing of the water supply valves 191 and 192 repeatedly.

[0096] According to this, while the water supply is stopped, the device waits for bubbles that could not be removed while the water was being supplied to move to a place where the water flows by gravity, etc. Therefore, the bubbles can be effectively removed without consuming excessive water.

[0097] The pre-wash process is executed including a drainage process in which the drain valve 21 is opened to drain the water from the water tank 12. The duration of the drainage process during the main wash process, i.e., the drainage period Tmd, is set longer than the duration of the drainage process during the pre-wash process, i.e., the drainage period Tpd.

[0098] In the main washing process, there is a higher possibility of foam generation than in the pre-washing process. In this embodiment, the length of the drainage period Tmd in the main washing process is set to be longer than the period required for drainage, and a waiting period is provided for a while after the drainage is actually completed, thereby encouraging the foam to be discharged outside the machine or to disappear. This reduces the amount of foam remaining in the spin tub 13, improving the finish of the laundry.

[0099] Here, when the washing water containing a washing treatment agent such as detergent is circulated by the circulation pump 23, the washing water is agitated and foamed easily. In the pre-wash process, the operation starts when the laundry is in a dry state, so it is necessary to secure a circulation period Tpe so that the laundry can be sufficiently permeated with water. On the other hand, particularly in the main wash process, if the circulation period Tme is too long, a large amount of foam may be generated.

[0100] In contrast, washing machine 10 includes circulation path 22 and circulation pump 23. Circulation path 22 connects drainage section 123 provided at the bottom of water tub 12 to nozzle section 221 provided at the top of water tub 12. Circulation pump 23 circulates the water in water tub 12 through circulation path 22. The pre-wash process and main wash process each include circulation periods Tpe and Tme during which control device 25 drives circulation pump 23. The length of circulation period Tme in the main wash process is set shorter than the length of circulation period Tpe in the pre-wash process.

[0101] According to this, in the main washing process in which the laundry has been sufficiently saturated with water in the pre-washing process, the circulation period Tme for driving the circulation pump 23 is set to be relatively short. Therefore, in the main washing process in which foam is likely to be generated, the generation of a large amount of foam can be suppressed. Therefore, the finish of the laundry can be improved.

[0102] Here, since the circulating water flowing through circulation path 22 is usually discharged toward the clothes located near rotatable tub end plate 132 inside rotatable tub 13, the circulating water is unlikely to splash on the inside of door 15. Therefore, if bubbles adhere to the inside of door 15, it may be difficult to remove them using only the circulating water.

[0103] In contrast, outer box 11 has opening 112 at the front. Washing machine 10 includes door 15, circulation path 22, and circulation pump 23. Door 15 opens and closes opening 112. Circulation path 22 connects drainage section 123 provided at the bottom of water tub 12 to nozzle section 221, which is a water discharge section provided at the top of water tub 12. Circulation pump 23 circulates the water in water tub 12 through circulation path 22. In the rinsing process, control device 25 drives circulation pump 23 to flow water from nozzle section 221 toward door 15.

[0104] According to this, by deliberately directing the circulating water toward the door 15 side during the rinsing process, it becomes easy to remove any foam that adheres to the inside of the door 15 or the front of the water tub 12. This improves the finish of the laundry and increases the user's satisfaction with the finish.

[0105] Here, unless the circulation pump 23 is driven at a relatively high frequency, it cannot output a hydraulic force that can draw water up to the nozzle portion 221 provided at the top of the water tub 12. On the other hand, if the drive frequency of the circulation pump 23 is increased, the force of the circulating water being discharged increases, so that the water is discharged toward the rotating tub end plate 132 side of the rotating tub 13. Therefore, in order to discharge the water toward the door 15 side, it is necessary to reduce the drive frequency of the circulation pump 23.

[0106] In contrast, the rinsing step is performed including a high-frequency process and a low-frequency process. The high-frequency process is a process in which the circulation pump 23 is driven at a predetermined drive frequency that enables the water in the water tank 12 to circulate through the circulation path 22. The low-frequency process is a process performed after the high-frequency process, in which the circulation pump 23 is driven at a drive frequency lower than the predetermined drive frequency.

[0107] According to this, since circulating water can be sprayed on the inside of door 15, it becomes easier to remove bubbles adhering to the inside of door 15. Therefore, the finish of the laundry can be improved, and the user's satisfaction with the finish can be improved.

[0108] Here, in the rinsing step, the control device 25 rotates the rotatable tub motor 14. If the rotatable tub motor 14 continues to be driven after the foam on the inside of the door 15 and the like during the low drive frequency period has been washed away, the rotation of the rotatable tub 13 may agitate the water in the water tub 12, which may cause excessive foaming in the rotatable tub 13.

[0109] In response to this, in the rinsing step, the control device 25 opens the drain valve 21 after the low frequency treatment to drain water from the water tub 12. That is, the water in the water tub 12 is drained immediately after the end of the low frequency period Trg.

[0110] In this embodiment, the drain valve 21 is opened after the low-frequency processing is completed, i.e., after the low-frequency period Trg has elapsed, but this is not limited to the above. In other words, "opening the drain valve 21 after the low-frequency processing to drain water from the water tank 12" does not necessarily mean opening the drain valve 21 to drain water from the water tank 12 after the low-frequency processing is completed, i.e., after the low-frequency period Trg has elapsed, but also includes opening the drain valve 21 after the low-frequency processing has started and before the low-frequency processing is completed, i.e., before the low-frequency period Trg has elapsed. In other words, if enough stored water can be maintained in the water tank 12 to circulate the water by the circulation pump 23 during the low-frequency period Trg, the drain valve 21 may be opened before the low-frequency period Trg has elapsed.

[0111] This allows the water to be drained immediately after the foam on the inside of the door 15 is washed away, thereby suppressing foaming. This improves the finish of the laundry. Also, the user's satisfaction with the finish can be improved.

[0112] (Other embodiments) In the above embodiment, the length Tin of the period during which the first water supply valve 191 is opened throughout the entire bubble removal process, and the length Tjn of the period during which the first water supply valve 191 is closed are set to be constant, but this is not limited thereto. For example, in another embodiment, the length Tjn of the period during which the first water supply valve 191 is closed may be set to vary depending on the count n of the number of repetitions. For example, as shown in FIG. 14, the length Tjnmax of the period during which the first water supply valve 191 is closed the nmax time may be set to be shorter than the length Tj1 of the period during which the first water supply valve 191 is closed the first time. FIG. 14 shows an example in which the maximum number of repetitions nmax is 4 times. In this case, the periods Tj1 and Tj2 during which the first water supply valve 191 is closed in the first half of the bubble removal process, i.e., the first and second times, are set to 15 seconds, whereas the periods Tj3 and Tj4 during which the water supply valve 19 is closed in the second half of the bubble removal process, i.e., the third and fourth times, are set to 10 seconds. In this embodiment as well, the total period during which first water supply valve 191 is closed is set to be longer than the total period during which first water supply valve 191 is open throughout the entire bubble removal process.

[0113] According to this embodiment, during the bubble removal process, among the periods during which first water supply valve 191 is intermittently opened and closed, period Tjnmax during which first water supply valve 191 is closed the final time is set shorter than at least period Tj1 during which first water supply valve 191 is closed the initial time. In other words, during the final stage of the bubble removal process, period Tjn during which first water supply valve 191 is closed is set shorter than during the initial stage of the bubble removal process.

[0114] After first water supply valve 191 is repeatedly opened and closed multiple times in the foam removal process, it is assumed that the foam in spin tub 13 and the foam adhering to the inside of door 15 are washed away or disappear, and are removed to a certain extent. Therefore, in the final stage of the foam removal process, it is possible to shorten the waiting period for waiting for the foam remaining in spin tub 13 and the foam adhering to door 15 to move with the rotation of spin tub 13 or to move with water by its own weight. This shortens the execution period of the foam removal process and therefore the execution period of the entire washing operation, which leads to a reduction in power consumption and also contributes to user convenience.

[0115] In the example shown in FIG. 9 of the first embodiment and the example shown in FIG. 14 of the present embodiment, the length Tin of the period during which the first water supply valve 191 is opened is set constant throughout the entire foam removal process, but this is not limited to this. For example, the period Tinmax during which the first water supply valve 191 is opened the final time may be set shorter than at least the period Ti1 during which the first water supply valve 191 is closed the first time. That is, in the final stage of the foam removal process, the period Tin during which the first water supply valve 191 is opened may be set shorter than that in the initial stage of the foam removal process. This also shortens the execution period of the foam removal process and therefore the execution period of the entire washing operation, which leads to a reduction in power consumption and contributes to user convenience.

[0116] Furthermore, in the above embodiment, the circulating pump 23 is stopped in the final stage of the washing period Tmc in the main washing process, but this is not limited to the above. For example, in another embodiment, the control device 25 may be configured to execute high frequency processing and low frequency processing immediately before the drainage process, similar to the final rinsing process. This allows the foam adhering to the inside of the door 15 to be washed away before the rinsing step.

[0117] Although several embodiments of the present invention have been described above, these embodiments are presented as examples and are not intended to limit the scope of the invention. These novel embodiments can be implemented in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. These embodiments and their modifications are included in the scope and spirit of the invention, and are included in the scope of the invention and its equivalents described in the claims. [Explanation of symbols]

[0118] 10... washing machine (clothing treatment device), 11... outer box, 112... opening, 12... water tub, 123... drainage section, 124... water inlet, 13... rotating tub, 14... rotating tub motor, 15... door, 18... water supply path, 181... first water supply path (water supply path), 182... second water supply path, 19... water supply valve, 191... first water supply valve (water supply valve), 192... second water supply valve (water supply valve), 20... drainage path, 21 drain valve, 22... circulation path, 221... nozzle section (water discharge section), 23... circulation pump, 25... control device, 30... loading mechanism, 31... automatic loading device

Claims

1. Outer box and A water tank provided inside the outer box; A rotating tank rotatably provided within the water tank; a rotating tub motor for rotating the rotating tub; a water supply path for supplying water from an external water source to the water tank; a water supply valve that opens and closes the water supply path; A drainage path for draining water from the water tank; A drain valve that opens and closes the drain path; A control device capable of controlling the driving of the rotary tub motor, the opening and closing of the water supply valve, and the opening and closing of the drain valve to execute a washing operation including a washing process, a rinsing process, and a spin-drying process; The control device includes: In the washing process, a pre-washing process, a main washing process executed after the pre-washing process, and an intermediate dehydration process executed after the pre-washing process or the main washing process to discharge moisture contained in the laundry outside the machine can be executed, a defoaming process is performed before the intermediate dewatering process is performed after the main washing process, in which the water supply valve is opened to supply water while the drain valve is open; The main washing process is executed including a drainage process of opening the drain valve to drain the water in the water tank, The period of the drainage process in the main washing process is set to include a period required for drainage and a standby period. Clothes treatment device.

2. The control device executes the foam removal process after executing the drainage process in the main washing process. The clothing treatment device according to claim 1.

3. An automatic dispenser is provided for automatically dispensing a laundry treatment agent into the water tank, The pre-wash process or the main wash process includes a dosing process for driving the automatic dosing device to dosing the laundry treatment agent. The clothing treatment device according to claim 1.

4. The control device intermittently opens and closes the water supply valve during the bubble removal process to supply water. A clothing treatment device according to any one of claims 1 to 3.

5. In the bubble removing process, the length of the period during which the water supply valve is closed the final time is set to be shorter than the length of the period during which the water supply valve is closed the first time. The clothing treatment device according to claim 4.

6. The pre-washing process is performed including the drainage process, The duration of the drainage process during the main washing process is set to be longer than the duration of the drainage process during the pre-washing process. The clothing treatment device according to claim 2.

7. A circulation path connecting a drainage section provided at a lower part of the water tank and a water discharge section provided at an upper part of the water tank; a circulation pump that circulates the water in the water tank through the circulation path, each of the pre-washing process and the main washing process includes a circulation period during which the control device drives the circulation pump; The length of the circulation period in the main washing process is set to be shorter than the length of the circulation period in the pre-washing process. A clothing treatment device according to any one of claims 1 to 6.

8. The outer box has an opening at the front, A door for opening and closing the opening; A circulation path connecting a drainage section provided at a lower part of the water tank and a water discharge section provided at an upper part of the water tank; a circulation pump that circulates the water in the water tank through the circulation path, The control device drives the circulation pump in the rinsing step to cause water to flow from the water discharge portion toward the door side. A clothing treatment device according to any one of claims 1 to 7.

9. The rinsing process includes a high-frequency process in which the circulation pump is driven at a predetermined driving frequency that enables the water in the water tank to circulate through the circulation path, and a low-frequency process that is performed after the high-frequency process and drives the circulation pump at a driving frequency lower than the predetermined driving frequency. The clothing treatment device according to claim 8.

10. The control device, in the rinsing step, opens the drain valve to drain water from the water tank after the low frequency treatment. The clothing treatment device according to claim 9.

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