washing machine

Abstract

A washing machine comprises: a washing tub (3); a detergent box (4); a main water supply path (5) connected to the washing tub (3) in a manner passing through the detergent box (4); an auxiliary water supply path (24) connected to the washing tub (3) in a manner not passing through the detergent box (4); a main water supply valve (12) for opening and closing the main water supply path (5); an auxiliary water supply valve (25) for opening and closing the auxiliary water supply path (24); a drainage path (6) connected to the washing tub (3); a drainage valve (13) for opening and closing the drainage path (6); and a control unit (30). The control unit (30) performs a first process of filling an upstream area (6A) of the drainage path (6) with water in a water supply process of a washing operation and a second process of storing water in the washing tub (3) after the first process.

Description

Technical Field

[0001] The present invention relates to a washing machine. Background Art

[0002] The washer-dryer described in Patent Document 1 below includes an outer drum capable of storing water; a drum disposed within the outer drum and containing laundry; a water supply line connecting a faucet to the outer drum; a water supply valve disposed within the water supply line; a drain line connected to the lower end of the outer drum to drain water from the outer drum to the outside of the machine; and a drain valve disposed midway within the drain line. The outer drum and the drum constitute the washing drum. When the water supply valve is opened while the drain valve is closed, water from the faucet flows through the water supply line and is stored in the outer drum.

[0003] Although not disclosed in Patent Document 1, conventional washing machines are equipped with a detergent box to hold detergent, and a water supply line connected to the outer drum so as to pass through the detergent box. During the water supply process of such a washing machine's wash cycle, the water supply valve is opened while the drain valve is closed. Water flowing from the faucet through the water supply line carries the detergent in the detergent box through the washing tub and is then supplied to the bottom of the outer drum. A drain portion is formed at the bottom of the outer drum, connected to a drain line connected to a drain outlet. In this case, the detergent in the detergent box is supplied to the outer drum through the washing tub along with the water supplied from the faucet at the start of water supply. This initial water flows from the drain portion into the drain line and reaches the drain valve. Therefore, it is expected that most of the detergent supplied to the outer drum will flow down the drain line. After the water supply process, the detergent in the outer drum dissolves in the water due to the rotation of the drum. However, the mechanical force generated by the rotating drum does not affect the detergent flowing down the drain line, so this detergent is not easily dissolved in water, posing a risk of residual detergent. When this type of residual detergent is present, the detergent concentration in the water within the outer drum is low, reducing the effectiveness of the detergent in washing the laundry during the washing operation. Adding a circulation circuit and pump to return the detergent that has flowed down the drain to the outer drum can eliminate residual detergent that has flowed down the drain, but this inevitably increases costs.

[0004] Prior art literature

[0005] Patent Literature

[0006] Patent Document 1: Japanese Patent Application Laid-Open No. 2020-168231 Summary of the Invention

[0007] Problems to be solved by the invention

[0008] The present invention has been made based on this background, and an object of the present invention is to provide a washing machine that can suppress detergent supplied to a washing tub from flowing down to a drain at low cost.

[0009] Solutions for solving problems

[0010] The present invention is a washing machine comprising: a washing drum for accommodating laundry and capable of storing water; a detergent box for accommodating detergent; a main water supply path connected to the washing drum in a manner passing through the detergent box; an auxiliary water supply path connected to the washing drum in a manner not passing through the detergent box; a main water supply valve for opening and closing the main water supply path; an auxiliary water supply valve for opening and closing the auxiliary water supply path; a drainage path connected to the washing drum; a drain valve for opening and closing the drainage path; and a control unit for controlling the opening and closing of the main water supply valve, the auxiliary water supply valve, and the drain valve to perform water supply processing for a washing operation, wherein the control unit performs in the water supply processing: a first processing of filling the area between the drain valve and the washing drum in the drainage path with water by opening the auxiliary water supply valve while the main water supply valve and the drain valve are closed; and a second processing of storing water in the washing drum by opening the main water supply valve after the first processing while the drain valve is closed.

[0011] In addition, the present invention is characterized in that the washing machine also includes: a circulation path, having an outlet and a return port connected to the washing drum; an air supply unit, which circulates the air in the washing drum by taking the air from the outlet into the circulation path and returning it to the washing drum from the return port; a heating unit, which is provided in the circulation path and heats the air in the circulation path; and a drying filter, which is arranged in the circulation path in an upstream area on the outlet side of the heating unit and captures foreign matter from the air in the circulation path that goes from the outlet to the return port, the control unit controls the air supply unit and the heating unit to perform a drying operation, and a part of the auxiliary water supply path also serves as the upstream area.

[0012] Furthermore, the present invention is characterized in that the control unit opens both the main water supply valve and the sub-water supply valve in the second process.

[0013] Effects of the Invention

[0014] According to the present invention, during the water supply process of a washing machine's wash operation, first, in the first process, the auxiliary water supply valve is opened while the main water supply valve and drain valve are closed, filling the area between the drain valve and the washing tub in the drainage path with water from the auxiliary water supply channel. Then, in the subsequent second process, the main water supply valve is opened while the drain valve is closed, allowing water carrying detergent flowing through the main water supply channel and the detergent box to accumulate in the washing tub. Since the area between the drain valve and the washing tub in the drainage path is filled with water, the detergent supplied to the washing tub in the second process does not flow down the drainage path but remains in the washing tub.

[0015] This low-cost structure, which uses a second process to supply detergent and water into the washing tub after the area between the drain valve and the washing tub in the drain passage is filled with water in the first process, prevents the detergent supplied to the washing tub from flowing down the drain passage without being fully dissolved. This prevents a decrease in the detergent concentration in the water in the washing tub, allowing the laundry to be effectively cleaned with detergent water having a high detergent concentration during the washing operation. As a result, it is possible to cost-effectively prevent the detergent supplied to the washing tub from flowing down the drain passage.

[0016] Furthermore, according to the present invention, during the drying operation of a washing machine, air within the drum is drawn from the outlet into a circulation path and returned to the drum from the return port. This air is heated by the heating unit within the circulation path, becoming hot air, which dries the laundry within the drum. A drying filter, located upstream of the heating unit and closer to the outlet, captures foreign matter contained in the air flowing from the outlet to the return port within the circulation path. This prevents foreign matter from adhering to the heating unit.

[0017] A portion of the auxiliary water supply channel also serves as the upstream area of ​​the circulation channel. Therefore, water flowing through the auxiliary water supply channel is splashed onto the drying filter, removing foreign matter from the drying filter. This foreign matter is then carried through the outlet into the washing tub and then out into the drain. This water used to remove foreign matter from the drying filter can be diverted during the first treatment to fill the area between the drain valve and the washing tub in the drain channel. This reduces the risk of detergent supplied to the washing tub flowing down the drain channel.

[0018] Furthermore, according to the present invention, in the second process, both the main water supply valve and the sub-water supply valve are opened, so that the water level in the washing tub can be quickly raised. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 It is a schematic longitudinal sectional right side view of the washing machine according to one embodiment of the present invention.

[0020] Figure 2 This is a block diagram showing the electrical structure of a washing machine.

[0021] Figure 3 It is a schematic longitudinal sectional front view of the washing drum and surrounding structures in the washing machine.

[0022] Figure 4 It is a schematic longitudinal sectional front view of the washing drum and surrounding structures.

[0023] Figure 5 It is a schematic longitudinal sectional front view of the washing drum and surrounding structures.

[0024] Figure 6 This is a time chart showing the water supply process during the washing operation of the washing machine.

[0025] Description of Reference Numerals

[0026] 1: Washing machine; 3: Washing drum; 4: Detergent box; 5: Main water supply line; 6: Drain line; 6A: Upstream area; 12: Main water supply valve; 13: Drain valve; 20: Circulation line; 20D: Outlet; 20E: Return port; 20F: Upstream area; 21: Air supply unit; 22: Heating unit; 23: Drying filter; 24: Auxiliary water supply line; 25: Auxiliary water supply valve; 30: Control unit; L: Laundry. DETAILED DESCRIPTION

[0027] Hereinafter, embodiments of the present invention will be described in detail with reference to the accompanying drawings. Figure 1 1 is a schematic longitudinal sectional right side view of a washing machine 1 according to an embodiment of the present invention. Figure 1 The direction perpendicular to the paper is called the left-right direction X of the washing machine 1. Figure 1 The left and right direction in the figure is called the front and rear direction Y of the washing machine 1. Figure 1 The up-down direction in the figure is called the up-down direction Z of the washing machine 1. Figure 1 The inner side of the paper is called the left side X1. Figure 1 The front side of the paper is called the right side X2. Figure 1 The left side is called the front side Y1. Figure 1 The right side in the vertical direction Z is called the rear side Y2. In the vertical direction Z, the upper side is called the upper side Z1, and the lower side is called the lower side Z2. The left-right direction X and the front-back direction Y are included in the horizontal direction. The horizontal direction can be the horizontal direction H or a substantially horizontal direction slightly inclined relative to the horizontal direction H.

[0028] In this embodiment, washing machine 1 is primarily a drum-type washer-dryer. However, washing machine 1 may also be a vertical type washing machine, a twin-tub type washing machine, or a washing machine that omits the drying function and performs only a washing operation. Washing machine 1 includes a housing 2; a washing drum 3 and a detergent container 4 disposed within housing 2; a main water supply line 5 and a drainage line 6 connected to washing drum 3. Washing machine 1 also includes a drum 7 housed within washing drum 3 and containing laundry L; a motor 8 that rotates drum 7; and a drying unit 9 that dries laundry L within drum 7.

[0029] The housing 2 is formed in a box shape. The front surface 2A of the housing 2 is, for example, a vertical surface. The front surface 2A is formed with an opening 2B that allows the inside and outside of the housing 2 to communicate. The front surface 2A is provided with a door 10 that opens and closes the opening 2B.

[0030] The washing tub 3 is connected to the upper end of a damper 11 extending from the bottom wall 2C of the housing 2 toward the upper side Z1. As a result, the washing tub 3 and the drum 7 therein are elastically supported by the bottom wall 2C via the damper 11. The washing tub 3 comprises a cylindrical circumferential wall 3A centered on an axis J extending in the horizontal direction H and in the front-to-back direction Y; a disc-shaped rear wall 3B that blocks the hollow portion of the circumferential wall 3A from the rear side Y2; and an annular front wall 3C connected to the front edge of the circumferential wall 3A.

[0031] The back wall 3B is arranged vertically and has an outer peripheral portion 3D and a central portion 3E that protrudes one step further toward the rear side Y2 than the outer peripheral portion 3D. A through hole 3F is formed at the center of the central portion 3E, extending through the central portion 3E in the front-to-back direction Y along the axis J. The front wall 3C has an annular first portion 3G that protrudes from the front edge of the circumferential wall 3A toward the axis J; a cylindrical second portion 3H that protrudes from the inner peripheral edge of the first portion 3G toward the front side Y1; and an annular third portion 3I that protrudes from the front edge of the second portion 3H toward the axis J. An inlet and outlet 3J is formed on the inner side of the third portion 3I, communicating with the hollow portion of the circumferential wall 3A from the front side Y1. The inlet and outlet 3J is in a state of being opposed to and communicating with the opening 2B of the housing 2 from the rear side Y2.

[0032] The detergent box 4 is a hollow body that holds detergent and is located within the housing 2 in an area Z1 above the washing tub 3. At least a portion of the detergent box 4 is exposed from the front surface 2A or upper surface 2D of the housing 2. The exposed portion of the detergent box 4 that is exposed from the front surface 2A or upper surface 2D may be an openable and closable lid or drawer. The user can open or pull out this exposed portion to refill the detergent box 4 with detergent.

[0033] The main water supply path 5 includes: one end (not shown) connected to a faucet (not shown), the other end 5A connected to the second portion 3H of the front wall 3C of the washing tub 3, for example, the upper portion, and a middle portion 5B between the one end and the other end 5A. The middle portion 5B constitutes a part of the internal space of the detergent box 4. That is, the main water supply path 5 is connected to the washing tub 3 in a manner passing through the detergent box 4. During water supply, tap water from the faucet is supplied to the washing tub 3 through the main water supply path 5 and the detergent box 4. If there is no detergent in the detergent box 4, tap water is stored in the washing tub 3. If there is detergent in the detergent box 4, detergent water in which detergent is dissolved in tap water is stored in the washing tub 3. Hereinafter, tap water and detergent water are sometimes referred to as simply "water".

[0034] Washing machine 1 includes an openable and closable main water supply valve 12, which is provided in main water supply passage 5, for example, closer to the faucet than midway portion 5B. When open, main water supply valve 12 is in an operative (ON) state, opening main water supply passage 5 and allowing water supply. When closed, main water supply valve 12 is in an inoperative (OFF) state, closing main water supply passage 5 and stopping water supply.

[0035] The drain passage 6 is connected to the lower end of the washing tub 3, for example, the lower end of the peripheral wall 3A. The water in the washing tub 3 is drained from the drain passage 6 to the outside of the housing 2, that is, outside the machine.

[0036] Washing machine 1 includes an openable and closable drain valve 13 located midway along drain path 6. When open, drain valve 13 is in an operational state, opening drain path 6 and allowing drainage of washing tub 3. When closed, drain valve 13 is in an inoperative state, closing drain path 6 and preventing drainage. The area of ​​drain path 6 between drain valve 13 and washing tub 3 is referred to as upstream area 6A, while the area farther from drain valve 13 than washing tub 3 is referred to as downstream area 6B.

[0037] Drum 7 is a cylindrical body having a central axis aligned with axis J, and is slightly smaller than washing tub 3. In this embodiment, drum 7 is horizontally arranged with its central axis along horizontal direction H, but it may also be arranged with its central axis tilted relative to horizontal direction H. Drum 7 includes: a cylindrical circumferential wall 7A coaxially arranged with circumferential wall 3A of washing tub 3; a disc-shaped back wall 7B that blocks the hollow portion of circumferential wall 7A from rear side Y2; and an annular ring wall 7C that protrudes from the front edge of circumferential wall 7A toward axis J. Drum 7 has a plurality of through-holes 7D formed at least in circumferential wall 7A, through which water in washing tub 3 flows between washing tub 3 and drum 7. Therefore, the water level in washing tub 3 is aligned with the water level in drum 7. A support shaft 14 extending toward rear side Y2 along axis J is provided at the center of back wall 7B of drum 7. The rear end portion of the support shaft 14 passes through the through hole 3F of the back wall 3B of the washing tub 3 and is arranged on the rear side Y2 relative to the back wall 3B.

[0038] An inlet and outlet 7E is formed on the inner side of annular wall 7C, communicating with the hollow portion of circumferential wall 7A from the front side Y1. Inlet and outlet 7E is opposed to and communicates with inlet and outlet 3J of washing drum 3 and opening 2B of housing 2 from the rear side Y2. Inlet and outlet 3J and inlet and outlet 7E, along with opening 2B, are collectively opened and closed by door 10. Users of washing machine 1 place laundry L in and out of drum 7 via the open opening 2B, inlet and outlet 3J, and inlet and outlet 7E. Door 10 is provided with a gasket 15, which, when door 10 closes opening 2B, inlet and outlet 3J, and inlet and outlet 7E, adheres tightly to third portion 3I of front wall 3C of washing drum 3.

[0039] The motor 8 is arranged on the rear side Y2 of the back wall 3B of the washing tub 3 in the housing 2. As an example of the motor 8, a direct drive (DD: Direct Drive) motor can be used. The motor 8 is connected to the support shaft 14 provided on the drum 7. The torque generated by the motor 8 is transmitted to the support shaft 14, and the drum 7 rotates around the axis J along with the support shaft 14. It should be noted that a clutch mechanism (not shown) can also be provided between the motor 8 and the support shaft 14 to transmit or cut off the torque of the motor 8 to the support shaft 14.

[0040] The drying unit 9 includes: a circulation path 20 and an air supply section 21 for circulating the air in the washing drum 3; a heating section 22 for heating the circulating air; a drying filter 23 for capturing foreign matter contained in the circulating air; an auxiliary water supply path 24 for supplying water for automatic cleaning to the drying filter 23; and an auxiliary water supply valve 25 for opening and closing the auxiliary water supply path 24.

[0041] The circulation path 20 is a flow path arranged on the upper side Z1 of the washing tub 3 in the housing 2. The circulation path 20 includes: a middle portion 20A extending in the front-to-back direction Y; a rear portion 20B extending from the rear end of the middle portion 20A to the lower side Z2; and a front portion 20C extending from the front end of the middle portion 20A to the lower side Z2. An outlet 20D is formed at the front end of the lower end portion of the rear portion 20B. The outlet 20D is connected to a portion of the outer peripheral portion 3D of the back wall 3B of the washing tub 3 that is higher than the upper limit water level, and communicates with the inside of the washing tub 3 from the rear side Y2. A return port 20E is formed at the lower end of the front portion 20C. The return port 20E is connected to the upper end portion of the second portion 3H of the front wall 3C of the washing tub 3, and communicates with the inside of the washing tub 3 from the upper side Z1.

[0042] Air supply unit 21 is a so-called blower and includes rotary blades 21A disposed within circulation path 20 and a motor (not shown) that rotates rotary blades 21A. As rotary blades 21A rotate, as indicated by the thick dashed arrows, air within washing tub 3 (i.e., air within washing tub 3 and drum 7) is drawn into circulation path 20 through outlet 20D and then returned to washing tub 3 through return outlet 20E. Thus, the air within washing tub 3 circulates, sequentially flowing through washing tub 3 and circulation path 20.

[0043] The heating unit 22 is a heat exchanger in a heat pump or a conventional heater, and at least a portion of the heating unit 22 is located within the circulation path 20. The portion of the heating unit 22 located within the circulation path 20 includes a heat dissipation portion 22A. When the heating unit 22 is in operation, the heat dissipation portion 22A reaches a high temperature. As the air flowing through the circulation path 20 passes around the heat dissipation portion 22A, it is heated and becomes hot air. The area within the circulation path 20 closer to the outlet 20D than the heat dissipation portion 22A is referred to as the upstream region 20F. The rear end of the midway portion 20A and the rear portion 20B constitute the upstream region 20F.

[0044] The drying filter 23 is a mesh sheet or grille disposed, for example, longitudinally across the upstream region 20F of the circulation path 20. As air flowing from the outlet 20D to the return port 20E in the circulation path 20 passes through the drying filter 23, foreign matter such as dust and dirt contained in the air is captured by the drying filter 23 and retained on the upstream surface 23A of the drying filter 23 on the outlet 20D side.

[0045] The auxiliary water supply line 24 includes an upstream portion 24A connected to the portion of the main water supply line 5 that is closer to the faucet than the main water supply valve 12; and a downstream portion 24B formed by the upstream region 20F of the circulation line 20. In other words, a portion of the auxiliary water supply line 24 also serves as the upstream region 20F. The end of the upstream portion 24A connected to the downstream portion 24B enters the drying filter 23 in the upstream region 20F from the upper side Z1. As described above, the upstream region 20F is connected to the washing tub 3 at the outlet 20D. This auxiliary water supply line 24 is connected to the washing tub 3 without passing through the detergent box 4.

[0046] The auxiliary water supply valve 25 is provided at the upstream portion 24A of the auxiliary water supply line 24. When the auxiliary water supply valve 25 is open, it is in an operative state, opening the auxiliary water supply line 24 and allowing water to be supplied to the washing tub 3 via the auxiliary water supply line 24. When the auxiliary water supply valve 25 is closed, it is in an inoperative state, closing the auxiliary water supply line 24 and preventing water from being supplied to the washing tub 3 via the auxiliary water supply line 24.

[0047] The washing machine 1 further includes a control unit 30 . Figure 2 This is a block diagram showing the electrical structure of washing machine 1. The control unit 30 is configured as a microcomputer, for example, including a CPU (central processing unit), memory such as ROM (read-only memory) or RAM (random access memory), and a timer for timing. It is built into the housing 2. The motor 8, main water supply valve 12, drain valve 13, air supply unit 21, heating unit 22, and auxiliary water supply valve 25 are each electrically connected to the control unit 30. The control unit 30 controls the operation of each of these components to execute the washing and drying operation. The washing and drying operation includes an initial washing process, one or more rinsing processes performed after the washing process, a spin cycle performed at least after the final rinsing process, and a final drying process. These processes can also be independent operations; in this case, for example, the washing process is the washing process and the drying process is the drying process. The washing machine 1 also includes a water level sensor 31 for detecting the water level in the washing tub 3. A known sensor can be used as the water level sensor 31. The detection value of the water level sensor 31 is input to the control unit 30 in real time.

[0048] During the washing process, the control unit 30 first controls the opening and closing of the main water supply valve 12, the auxiliary water supply valve 25 and the drain valve 13 to perform water supply processing. Figures 3 to 5 and a timing chart showing water supply processing during cleaning operation Figure 6 , explains the water supply treatment for the cleaning process. Figure 6 In the time chart, the horizontal axis represents elapsed time, and the vertical axis represents, from top to bottom, the detection value of the water level sensor 31, i.e., the water level in the washing tub 3; the active / inactive status of the main water supply valve 12; the active / inactive status of the auxiliary water supply valve 25; and the status of the motor 8. The status of the motor 8 includes a stopped state, a forward rotation state, and a reverse rotation state. It should be noted that the drain valve 13 is always closed during the water supply process.

[0049] In the water supply process, the control unit 30 opens the auxiliary water supply valve 25 and the main water supply valve 12 in sequence while the drain valve 13 is closed. Figure 3 As shown by arrow A1, the detergent in the detergent box 4 is carried by the water flowing through the main water supply channel 5 into the washing tub 3 and does not remain in the washing tub 3 but flows down to the upstream area 6A of the drainage channel 6. Therefore, the concentration of the detergent in the water in the washing tub 3 becomes lower.

[0050] Therefore, in the water supply process of this embodiment, as the first process, the control unit 30 opens the auxiliary water supply valve 25 ( Figure 6 At the moment T0). Thus, Figure 4 As shown by arrow A2, tap water from the auxiliary water supply path 24 flows through the washing tub 3 into the upstream area 6A of the drain path 6. When the auxiliary water supply valve 25 is opened for a predetermined time, as shown in FIG. Figure 4 As shown by the hatched lines, the upstream area 6A is filled with tap water.

[0051] Afterwards, when the water level in the washing tub 3 rises to a water level W1 below the lower end of the circumferential wall 7A of the drum 7 as the tap water overflows from the upstream area 6A, the control unit 30 ends the first process and executes the second process ( Figure 6 The first treatment ends at the time when the water level sensor 31 detects that the water level in the washing tub 3 has risen to the water level W1, or at the time when a predetermined time determined by experiments has passed since time T0. As a second treatment, the control unit 30 closes the auxiliary water supply valve 25 while the drain valve 13 is still closed and opens the main water supply valve 12. In this way, the detergent water flowing through the main water supply path 5 and carrying the detergent in the detergent box 4 is Figure 5 As shown by arrow A3, water flows into and accumulates in washing tub 3. As a result, the water level in washing tub 3 rises from water level W1.

[0052] The first treatment fills the upstream area 6A of the drain 6 between the drain valve 13 and the washing tub 3 with tap water. Therefore, the detergent supplied to the washing tub 3 during the subsequent second treatment does not flow down the drain 6 but remains within the washing tub 3. This structure, in which the upstream area 6A of the drain 6 is filled with tap water during the first treatment and then the detergent and water are supplied to the washing tub 3 during the second treatment, prevents the detergent supplied to the washing tub 3 from flowing down the drain 6 without being fully dissolved. This allows for a low-cost configuration that eliminates the need for a pump or the like for returning water from the drain 6 to the washing tub 3. Consequently, the detergent supplied to the washing tub 3 can be prevented from flowing down the drain 6 at a low cost.

[0053] When the water level in the washing tub 3 rises to the water level W2 in the middle of the water supply, the control unit 30 closes the main water supply valve 12 and opens the auxiliary water supply valve 25, so that the motor 8 is operated and the motor 8 is repeatedly rotated forward and reverse ( Figure 6 At time T2, drum 7 rotates forward as motor 8 rotates forward, and reverses as motor 8 rotates reversely. The forward and reverse rotations of drum 7 promote the infiltration of detergent water into the laundry L within drum 7, thereby lowering the water level within washing tub 3. Furthermore, the forward and reverse rotations of drum 7 actively dissolve detergent in tap water within washing tub 3, resulting in a high concentration of detergent water within washing tub 3.

[0054] When the forward and reverse rotation of the motor 8 continues for a predetermined time, the control unit 30 stops the motor 8 and opens the main water supply valve 12 ( Figure 6 At time T3). Thus, in the second process, the controller 30 opens both the main water supply valve 12 and the auxiliary water supply valve 25. This causes the water level in the washing tub 3 to rise again. With both the main water supply valve 12 and the auxiliary water supply valve 25 open, the water level in the washing tub 3 can rise rapidly. It should be noted that if the detergent in the detergent box 4 has completely drained, only tap water is supplied from the main water supply line 5 to the washing tub 3.

[0055] When the water level in the washing tub 3 exceeds the water level W2 and rises to the target water level W3, the control unit 30 closes the main water supply valve 12 and the auxiliary water supply valve 25, and operates the motor 8 to repeatedly rotate forward and reverse ( Figure 6 As described above, the water level in the washing tub 3 decreases as the motor 8 rotates forward and reverse. However, due to the forward and reverse rotation of the motor 8 at the time T2 to T3 immediately before, the detergent water has basically penetrated into the laundry L in the washing tub 3. Therefore, the water level in the washing tub 3 decreases slowly after the time T4. When the forward and reverse rotation of the motor 8 continues for a predetermined time, the control unit 30 temporarily stops the motor 8 while continuing to close the main water supply valve 12 and the auxiliary water supply valve 25 ( Figure 6 time T5).

[0056] After that, the control unit 30 opens the main water supply valve 12 while continuing to close the auxiliary water supply valve 25 ( Figure 6 When the water level in the washing tub 3 rises to the water level W3, the control unit 30 closes the main water supply valve 12 and repeatedly rotates the motor 8 forward and reverse ( Figure 6 After that, the control unit 30 temporarily stops the motor 8 while continuing to close the main water supply valve 12 and the auxiliary water supply valve 25 ( Figure 6 After that, the additional water supply consisting of opening the main water supply valve 12, forward and reverse rotation of the motor 8, and temporary stop of the motor 8 is repeated a predetermined number of times ( Figure 6 After time T9 (after), the controller 30 ends the second process by closing the main water supply valve 12 and the auxiliary water supply valve 25. This completes the entire water supply process. It should be noted that during the second process, the main water supply valve 12 is not always open, but rather is opened intermittently. This stabilizes the water level in the washing tub 3, allowing the water level sensor 31 to accurately detect the water level in the washing tub 3.

[0057] As a cleaning process after the water supply process, the control unit 30 rotates the drum 7 through the motor 8. As a result, the laundry L in the drum 7 is tumbling. During the tumbling, the laundry L is repeatedly lifted to a certain extent and then naturally falls to the water surface. Dirt is removed from the laundry L by the impact generated by the tumbling and the high concentration of detergent components contained in the detergent water stored in the drum 7. Since the concentration of the detergent in the water in the washing drum 3 can be suppressed from decreasing as described above, the laundry L can be quickly and effectively cleaned by the detergent water with a high detergent concentration during the cleaning process. When the control unit 30 opens the drain valve 13 to drain water after a specified time has passed since the start of tumbling, the cleaning process ends.

[0058] During the rinsing cycle, the controller 30 opens the main water supply valve 12 for at least a predetermined time while the drain valve 13 is closed to supply water to the washing tub 3. The controller then rotates the drum 7 via the motor 8. This process repeats the tumbling process described above, so that the laundry L is rinsed by the tap water within the drum 7. The rinsing cycle ends when the controller 30 drains the water after a predetermined time has passed since the start of tumbling.

[0059] During the spin cycle, controller 30 spins drum 7 with drain valve 13 open. The centrifugal force generated by the spin cycle of drum 7 dehydrates laundry L within drum 7. Water that leaks from laundry L during the spin cycle is drained from the machine through drain 6. The spin cycle may be performed not only after the rinsing cycle but also after the washing cycle.

[0060] During the drying process, the controller 30 controls the air supply unit 21 and the heating unit 22 to generate hot air. This hot air circulates between the drum 7 and the circulation path 20, supplying the laundry L within the drum 7. This dries the laundry L. During the washing operation, foreign matter, as described above, is carried along by the hot air during the drying process and captured by the drying filter 23 within the circulation path 20. This prevents foreign matter from adhering to and accumulating in the heat dissipation portion 22A of the heating unit 22, thereby preventing performance degradation associated with reduced heating efficiency of the heating unit 22 and poor air flow in the circulation path 20.

[0061] After the drying process, that is, after the washing and drying operation, the controller 30 opens the auxiliary water supply valve 25 as a maintenance operation for the drying filter 23. It should be noted that the main water supply valve 12 can also be located in the main water supply line 5, upstream of the connection with the auxiliary water supply line 24, to the faucet. In this case, the controller 30 opens both the main water supply valve 12 and the auxiliary water supply valve 25. Tap water from the faucet flows from the main water supply line 5 to the auxiliary water supply line 24. Alternatively, the auxiliary water supply line 24 can be connected directly to the faucet instead of the main water supply line 5.

[0062] Water flowing from upstream portion 24A into downstream portion 24B in auxiliary water supply passage 24 is splashed from upper side Z1 onto drying filter 23, located in downstream portion 24B, i.e., upstream region 20F of circulation passage 20. This causes foreign matter on upstream surface 23A of drying filter 23 to peel off and fall, carried by the water to outlet 20D of circulation passage 20. It should be noted that downstream portion 24B may be equipped with a nozzle, pump, or the like for forcefully spraying tap water from upstream portion 24A toward drying filter 23, or a wiper or the like that rotates under the control of control unit 30 to scrape foreign matter from upstream surface 23A.

[0063] Foreign matter and water that reach the outlet 20D fall from the outlet 20D into the washing tub 3. At this time, when the drain valve 13 is open, the foreign matter and water will flow through the drain path 6 and be discharged outside the machine. It should be noted that a drain filter (not shown) can also be provided in the upstream portion of the drain path 6 closer to the washing tub 3 than the drain valve 13. In this case, foreign matter flowing through the drain path 6 is captured by the drain filter and recovered by the user when maintaining the drain filter. As the drain filter, a known structure that can be disassembled and installed in the housing 2 by the user during maintenance can be used.

[0064] As described above, water flowing through auxiliary water supply passage 24 is splashed onto drying filter 23, thereby removing foreign matter from drying filter 23. The water then flows into washing tub 3 through outlet 20D, carrying the foreign matter, and then out into drain passage 6. The water used for automatic cleaning, thus removing foreign matter from drying filter 23, can be diverted during the first step to fill upstream area 6A of drain passage 6 between drain valve 13 and washing tub 3. This allows for more cost-effective suppression of detergent supplied to washing tub 3 from flowing down drain passage 6.

[0065] The present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the claims.

[0066] For example, the main water supply valve 12 and the auxiliary water supply valve 25 may be configured as universal multi-way valves. Furthermore, multiple auxiliary water supply lines 24 may be provided for various purposes, such as automatic cleaning of the drying filter 23. The water flowing through the auxiliary water supply lines 24 is not limited to tap water; it may also be bath water. The same applies to the water flowing through the main water supply line 5.

[0067] The detergent box 4 may contain not only detergent but also softener. In this case, the detergent box 4 is configured to selectively carry detergent and softener to the water in the main water supply channel 5. The softener is supplied to the washing tub 3 during the water supply process during the rinsing process.

Claims

1. A washing machine, characterized in that: include: A washing drum, which holds laundry and can store water; a detergent box for containing detergent; a main water supply line connected to the washing tub in a manner of passing through the detergent box; an auxiliary water supply channel connected to the washing tub without passing through the detergent box; A main water supply valve, for opening and closing the main water supply line; Auxiliary water supply valve, opening and closing the auxiliary water supply line; a drainage channel connected to the washing tub; a drain valve to open and close the drain passage; and The control unit controls the opening and closing of the main water supply valve, the auxiliary water supply valve, and the drain valve to perform water supply processing for the washing operation. The control unit performs, in the water supply process, a first process of filling the area between the drain valve and the washing tub in the drain passage with water by opening the auxiliary water supply valve while the main water supply valve and the drain valve are closed; and a second process of storing water in the washing tub by opening the main water supply valve while the drain valve is closed after the first process.

2. The washing machine according to claim 1, wherein Also includes: A circulation path having a take-out port and a return port connected to the washing tub; an air supply unit for circulating the air in the washing tub by taking the air out from the outlet into the circulation path and returning the air from the return outlet into the washing tub; a heating unit, disposed in the circulation path, for heating the air in the circulation path; as well as The drying filter is arranged in the circulation path in an upstream region closer to the outlet than the heating unit, and captures foreign matter from the air flowing from the outlet to the return port in the circulation path. The control unit controls the air supply unit and the heating unit to perform a drying operation, and a portion of the auxiliary water supply passage also serves as the upstream region.

3. The washing machine according to claim 1 or 2, characterized in that: The control unit opens both the main water supply valve and the sub-water supply valve in the second process.

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