JP7611548B2 - washing machine - Google Patents

Description

This invention relates to a washing machine.

The washing machine described in Patent Document 1 below includes a water tub, a washing/spinning tub arranged inside the water tub, and a motor that rotates the washing/spinning tub. In the washing machine, when the washing/spinning tub rotates after water is supplied into the washing/spinning tub, a water flow occurs in the water tub, generating bubbles between the washing/spinning tub and the water tub, thereby cleaning the tub.

JP 2009-39318 A

Not only in the washing machine of Patent Document 1, but in the washing tub of a general washing machine, mold can grow inside the tub, using biofilms made of detergent residue and sebum dirt (hereinafter simply referred to as "dirt") remaining after the washing cycle as nutrients, and can be distributed in ring shapes around the circumference of the washing tub. Biofilms often grow near the surface of the water that accumulates in the washing tub during the washing cycle, so in order to prevent the growth of biofilms, i.e., mold growth, it is necessary to remove dirt that is relatively high up inside the washing tub.

A typical washing tub has an overflow port at the top to drain water that exceeds a certain water level in the washing tub, but the dirt mentioned above can also be present in the washing tub at a higher position than the overflow port due to water splashing, etc. However, in the case of the tub cleaning method of Patent Document 1, it is difficult to remove dirt above the overflow port in the washing tub. In the first place, with the tub cleaning method of Patent Document 1, there is a risk of mold growth due to bubbles remaining between the washing/spinning tub and the water tub, and there is also a risk that the motor will be restricted and broken down if the washing/spinning tub cannot rotate smoothly due to the bubbles acting as resistance.

This invention was made against this background, and aims to provide a washing machine that can effectively clean the washing tub.

The present invention relates to a washing machine having a drive unit that generates torque, an outer tub that is provided with a drain outlet, an overflow outlet that is positioned higher than the drain outlet, and an opening that is positioned higher than the overflow outlet and that stores water, an inner tub that is disposed within the outer tub and that is provided with a through hole for passing water between the outer tub and the drain outlet, and an inlet/outlet that faces the opening from below, and that receives the torque of the drive unit to rotate and that is connected to the drain outlet and the inner tub that is provided with a through hole for passing water between the outer tub and the drain outlet, and an inlet/outlet that faces the opening from below, and that receives the torque of the drive unit to rotate and that rotates. The washing machine includes a drainage channel for draining water from the washing tub, an overflow channel connected to the overflow port and directing water in the washing tub from the overflow port to the drainage channel, a water supply unit for supplying water to the washing tub, an upper surface portion provided with a water receiving port for receiving water from the water supply unit, an outer periphery portion provided with a water outlet located at a higher position than the overflow port, a water storage unit for storing water that falls through the water receiving port, and a guideway for directing water in the water storage unit to the water outlet, and a hollow tub cleaning member fixed to the inner tub.

The present invention is also characterized in that the water outlet opens radially outward from the rotation axis of the inner tank, or in a tangential direction to the circumferential direction around the rotation axis.

The present invention is also characterized in that the flow path area in the downstream region of the conduit on the discharge port side is equal to or smaller than the flow path area in the upstream region of the conduit on the water storage section side.

The present invention is also characterized in that the tank cleaning member has a partition that divides the internal space of the tank cleaning member into multiple water storage sections.

The present invention is also characterized in that the tub cleaning member is provided with a water supply port that allows water from the water storage section to fall into the washing tub.

In the washing machine according to the present invention, when water is supplied into the washing tub by the water supply unit, the water passes through the through holes in the inner tub and flows back and forth between the outer tub and the inner tub, and accumulates throughout the washing tub. The water in the washing tub is discharged from the drain outlet of the outer tub through the drainage path. When the water level in the washing tub rises to an overflow outlet located in the outer tub at a higher position than the drain outlet, the water on the water surface side, i.e., the upper side, is guided from the overflow outlet through the overflow path to the drainage path and discharged through the drainage path. Laundry is put in and taken out of the inner tub through an opening located in the outer tub at a higher position than the overflow outlet and an inlet and outlet of the inner tub.

When the tub cleaning member fixed to the inner tub receives water from the water supply unit through the water receiving port on the top surface, the water falls through the receiving port and accumulates in the water storage unit. When the tub cleaning member rotates together with the inner tub, centrifugal force causes the water in the water storage unit to pass through the guideway and reach the water outlet on the outer periphery of the tub cleaning member, where it is discharged from the water outlet. Because the water outlet is positioned higher than the overflow port, the water discharged from the water outlet can reach dirt that is higher than the overflow port in the washing tub and remove this dirt. This allows the washing tub to be cleaned effectively.

In addition, according to the present invention, the water outlet opens radially outward from the rotation axis of the inner tub, or in a tangential direction to the circumferential direction around the rotation axis, so that the water discharged from the water outlet can be sprayed onto dirt located at a height higher than the overflow port on the inner circumferential surface of the outer tub, effectively removing the dirt. In this way, the washing tub can be cleaned even more effectively.

In addition, according to the present invention, the flow path area in the downstream region of the conduit on the water outlet side is equal to or less than the flow path area in the upstream region of the conduit on the water storage side, so that the water in the conduit is forcefully discharged from the water outlet and splashed onto dirt in the washing tub that is at a height higher than the overflow port. This makes it possible to effectively remove this dirt, and therefore to clean the washing tub even more effectively.

In addition, according to the present invention, the internal space of the tub cleaning member is divided into multiple water storage sections by partitions, making each water storage section smaller. This allows water to be quickly stored in each water storage section, so preparations for cleaning the washing tub can be completed quickly.

In addition, according to the present invention, the tub cleaning member is provided with a water supply port that allows water in the water storage section to fall into the washing tub. Therefore, when the washing tub is not being cleaned, water can be supplied to the washing tub by allowing water from the water supply section to fall from the water supply port into the washing tub via the water storage section of the tub cleaning member.

1 is a schematic vertical sectional right side view of a washing machine according to an embodiment of the present invention; FIG. 2 is an enlarged view of the tank cleaning member extracted from FIG. 1 . FIG. 3 is a cross-sectional view taken along the line AA in FIG. 2. FIG. 2 is an enlarged view of a main part in FIG. 10 is a flowchart showing a tub cleaning process executed in the washing machine.

The following describes in detail an embodiment of the present invention with reference to the drawings. FIG. 1 is a vertical cross-sectional right side view of a washing machine 1 according to an embodiment of the present invention. The direction perpendicular to the plane of FIG. 1 is referred to as the left-right direction X of the washing machine 1, the left-right direction in FIG. 1 is referred to as the front-rear direction Y of the washing machine 1, and the up-down direction in FIG. 1 is referred to as the up-down direction Z of the washing machine 1. In the left-right direction X, the back side in the plane of FIG. 1 is referred to as the left side X1, and the front side in the plane of FIG. 1 is referred to as the right side X2. In the front-rear direction Y, the left side in FIG. 1 is referred to as the front side Y1, and the right side in FIG. 1 is referred to as the rear side Y2. In the up-down direction Z, the upper side is referred to as the upper side Z1, and the lower side is referred to as the lower side Z2.

The washing machine 1 includes a housing 2 forming its outer shell, an outer tub 3 housed within the housing 2 to store water, an inner tub 4 housed within the outer tub 3, a rotor 5 housed within the inner tub 4, a motor 6 as an example of a drive unit that generates torque to rotate the inner tub 4 and the rotor 5, and an electric transmission mechanism 7 that transmits the torque of the motor 6 to the inner tub 4 and the rotor 5. The outer tub 3 and the inner tub 4 together form a washing tub 8. The washing machine 1 includes a balancer 9 attached to the upper end of the inner tub 4, and a tub cleaning member 10 fixed to the balancer 9.

The housing 2 is made of metal, for example, and is formed in a box shape. An opening 2B that connects the inside and outside of the housing 2 is provided on the top surface 2A. A door 11 for opening and closing the opening 2B is provided on the top surface 2A. A display operation unit 12 consisting of a liquid crystal operation panel or the like is provided in the area around the opening 2B on the top surface 2A. A user of the washing machine 1 can freely select the operating conditions of the washing machine 1 and instruct the washing machine 1 to start or stop operation by operating switches or the like on the display operation unit 12. Information related to the operation of the washing machine 1 is visually displayed on the liquid crystal panel or the like of the display operation unit 12.

The outer tank 3 is made of resin, for example, and is formed into a cylindrical shape with a bottom. The outer tank 3 has an axis J that extends in the vertical direction Z at its center. In the following, the circumferential direction around the axis J is referred to as the circumferential direction S, and the radial direction based on the axis J is referred to as the radial direction R. Within the radial direction R, the direction away from the axis J is referred to as the outside of the radial direction R, i.e., the radially outer direction R1, and the direction approaching the axis J is referred to as the inside of the radial direction R, i.e., the radially inner direction R2.

The outer tank 3 has a generally cylindrical circumferential wall 3A arranged along the vertical direction Z, a bottom wall 3B that closes the hollow portion of the circumferential wall 3A from the lower side Z2, and a ring-shaped annular wall 3C that borders the upper edge of the circumferential wall 3A and extends radially inward R2. An overflow port 3D that penetrates the circumferential wall 3A in the radial direction R is provided at the upper part of the circumferential wall 3A.

The bottom wall 3B is formed in a disk shape extending substantially horizontally, and a through hole 3E is provided at the center of the circle, penetrating the bottom wall 3B in the vertical direction Z. A drainage port 3F is provided in the bottom wall 3B at a position away from the through hole 3E, penetrating the bottom wall 3B in the vertical direction Z. The annular wall 3C is sometimes called an "outer tank cover." An opening 3G is provided on the inside of the annular wall 3C, which communicates with the hollow portion of the circumferential wall 3A from the upper side Z1. The opening 3G faces the opening 2B of the housing 2 from the lower side Z2, and is in communication with it.

A relay port 3H is provided at one location on the circumference of the annular wall 3C, which in this embodiment is at the rear end of the annular wall 3C, penetrating the annular wall 3C in the vertical direction Z. The opening 3G and relay port 3H are positioned higher than the overflow port 3D, which is positioned higher than the drain port 3F.

The washing machine 1 further includes a water supply unit 13 that supplies water to the washing tub 8, a drainage channel 14 that is connected to the drain outlet 3F and has a portion drawn outside the housing 2, i.e., outside the machine, and an overflow channel 15 that connects the overflow outlet 3D and the drainage channel 14. The water supply unit 13 includes a detergent case 16 that is located on the upper side Z1 of the relay port 3H of the outer tub 3 inside the housing 2, a water supply channel 17 that is connected to a tap water faucet (not shown) and has a portion drawn into the housing 2, and a water supply valve 18 provided midway along the water supply channel 20.

An example of the detergent case 16 includes a box-shaped main body 16A fixed to the housing 2, and a drawer 16B housed within the main body 16A and partially exposed to an opening 2B of the housing 2. Almost the entire top surface of the main body 16A is open, opening the inside of the main body 16A to the upper side Z1. The main body 16A is provided with a cylindrical water conduit 16C that protrudes from its bottom wall toward the lower side Z2.

The lower end of the water conduit 16C is located directly above the relay port 3H of the outer tub 3. In this embodiment, the lower end of the water conduit 16C is located away from the relay port 3H on the upper side Z1, but may be connected to the relay port 3H. The user pulls out the drawer 16B, which is in the storage position shown in FIG. 1, and pours detergent into the drawer 16B. When the user then pushes the drawer 16B back into the storage position, the detergent is set inside the main body 16A.

In this embodiment, the portion 17A of the water supply passage 17 located inside the housing 2 extends in the vertical direction Z, and the lower end of this portion 17A faces the inside of the main body 16A of the detergent case 16 from the upper side Z1. When the water supply valve 18 opens, water from the faucet falls from the water supply passage 17 into the main body 16A, carrying the detergent in the main body 16A and then falls from the water conduit 16C into the relay port 3H of the outer tub 3. The subsequent process will be described in detail later, but the water that falls into the relay port 3H is stored in the outer tub 3. When the water supply valve 18 closes, the supply of water to the outer tub 3, i.e., the washing tub 8, is stopped.

A drain valve 19 is provided in the drainage channel 14. When the drain valve 19 is closed, water remains in the outer tub 3. When the drain valve 19 is open, the water in the outer tub 3 is discharged outside the machine through the drainage channel 14. The overflow channel 15 has one end (not shown) connected to the overflow port 3D of the outer tub 3, and the other end 15A connected to a downstream portion of the drainage channel 14 that is farther away from the drainage port 3F of the outer tub 3 than the drain valve 19. When the water level in the outer tub 3 rises to the overflow port 3D, the water on the upper side Z1 in the outer tub 3 overflows from the overflow port 3D into the overflow channel 15, is guided by the overflow channel 15 to the drainage channel 14, and is then discharged outside the machine.

The inner tub 4 is made of metal, for example, and is formed into a cylindrical shape with a bottom that is slightly smaller than the outer tub 3, and can store laundry inside. The inner tub 4 has a substantially cylindrical circumferential wall 4A arranged along the vertical direction Z, and a bottom wall 4B provided at the lower end of the inner tub 4 and closing the hollow portion of the circumferential wall 4A from the lower side Z2.

The inner circumferential surface of the circumferential wall 4A and the upper surface of the bottom wall 4B form the inner surface of the inner tub 4. An opening 4C is provided at the upper end of the inner tub 4, bordered by the upper end of the inner circumferential surface of the circumferential wall 4A. The opening 4C exposes the hollow portion of the circumferential wall 4A to the upper side Z1 and faces the opening 3G of the outer tub 3 from the lower side Z2 and communicates with it. A user puts laundry (not shown) in and takes it out of the inner tub 4 from the upper side Z1 through the open openings 2B, 3G, and opening 4C.

The inner tub 4 is arranged coaxially within the outer tub 3. When housed within the outer tub 3, the inner tub 4 can rotate around the axis J as the axis of rotation. In this embodiment, the axis J passes through the center of the inner tub 4 and extends vertically, but it may extend in an inclined direction relative to the vertical direction. As an example, the inclined direction is a direction shifting toward the front side Y1 as it moves toward the upper side Z1. At least one of the circumferential wall 4A and the bottom wall 4B of the inner tub 4 has a plurality of through holes 4D, and water in the outer tub 3 can move between the outer tub 3 and the inner tub 4 through the through holes 4D. As a result, water is stored in the inner tub 4 and accumulates throughout the washing tub 8, and the water level in the outer tub 3 and the water level in the inner tub 4 are the same.

The bottom wall 4B of the inner tank 4 is formed in a disk shape extending generally parallel to and spaced apart from the bottom wall 3B of the outer tank 3 on the upper side Z1. A through hole 4E penetrating the bottom wall 4B in the vertical direction Z is provided at the circular center position of the bottom wall 4B coinciding with the axis J. A tubular support shaft 21 is provided in the bottom wall 4B, surrounding the through hole 4E and extending to the lower side Z2 along the axis J. The support shaft 21 is inserted through the through hole 3E in the bottom wall 3B of the outer tank 3, and the lower end of the support shaft 21 is located on the lower side Z2 of the bottom wall 3B.

The rotor 5 is a so-called pulsator, formed in a disk shape with the axis J as the center, and arranged on the bottom wall 4B inside the inner tank 4. The upper surface of the rotor 5 facing the entrance 4C of the inner tank 4 is provided with a plurality of raised portions 5A that are raised to the upper side Z1 and arranged radially with the axis J as the reference. The rotor 5 is provided with a rotating shaft 22 that extends from its center to the lower side Z2 along the axis J. The rotating shaft 22 is inserted into the hollow portion of the support shaft 21, and the lower end of the rotating shaft 22 is located on the lower side Z2 of the bottom wall 3B of the outer tank 3.

The motor 6 is an electric motor such as an inverter motor. The motor 6 is disposed inside the housing 2 on the lower side Z2 of the outer tub 3. The motor 6 has an output shaft 23 that rotates around an axis J, and generates torque and outputs it from the output shaft 23.

The transmission mechanism 7 is interposed between the lower ends of the support shaft 21 and the rotating shaft 22 and the upper end of the output shaft 23 protruding from the motor 6 to the upper side Z1. The transmission mechanism 7 selectively transmits the torque output from the output shaft 23 by the motor 6 to one or both of the support shaft 21 and the rotating shaft 22. A known clutch or the like is used as the transmission mechanism 7. When the torque from the motor 6 is transmitted to the support shaft 21, the inner tub 4 receives the torque of the motor 6 and is rotated around the axis J as the center of rotation. When the torque from the motor 6 is transmitted to the rotating shaft 22, the rotor 5 receives the torque of the motor 6 and is rotated around the axis J as the center of rotation.

The balancer 9 is an annular hollow body extending along the circumferential direction S, and is coaxially fixed to the upper end of the circumferential wall 4A of the inner tank 4. The balancer 9 reduces the vibration of the inner tank 4 during rotation, and the cavity 9A within the balancer 9 contains a liquid such as salt water to help reduce vibration.

The tank cleaning member 10 is a hollow annular body extending in the circumferential direction S, and is fixed coaxially to the upper end surface 9B of the balancer 9, thereby being fixed to the inner tank 4 via the balancer 9. The inner and outer diameters of the tank cleaning member 10 are the same as the inner and outer diameters of the balancer 9, respectively. Therefore, the inner surface of the inner wall 10A forming the inner periphery of the tank cleaning member 10 is flush with the inner surface 9C of the balancer 9, and the outer surface of the outer wall 10B forming the outer periphery of the tank cleaning member 10 is flush with the outer periphery 9D of the balancer 9.

Referring to FIG. 2, which shows the tank cleaning member 10 extracted from FIG. 1, the inner wall 10A and the outer wall 10B of the tank cleaning member 10 are annular plates arranged along the vertical direction Z and extending in the circumferential direction S. A water supply port 10C penetrating the inner wall 10A in the radial direction R is provided at the lower end of the inner wall 10A. A plurality of water supply ports 10C may be provided so as to be arranged at equal intervals in the circumferential direction S, or only one water supply port 10C may be provided so as to cover the entire area of the inner wall 10A in the circumferential direction S. A plurality of water outlets 10D are provided in the outer wall 10B so as to be arranged at equal intervals in the circumferential direction S. In this embodiment, each water outlet 10D opens toward the radially outward R1, but may also open toward the tangential direction T with respect to the circumferential direction S (see FIG. 4).

The upper end of the inner peripheral wall 10A and the upper end of the outer peripheral wall 10B are positioned at the same height. The tank cleaning member 10 has an upper wall 10E that is installed between the upper end of the inner peripheral wall 10A and the upper end of the outer peripheral wall 10B. The upper wall 10E is a thin plate in the vertical direction Z, and most of the upper surface portion 10EA extends horizontally in the radial direction R, but the outer edge 10EB on the radially outer side R1 and the inner edge 10EC on the radially inner side R2 may protrude one step upward Z1.

The lower end of the inner peripheral wall 10A and the lower end of the outer peripheral wall 10B are located at the same height in most areas in the circumferential direction S. However, at the same position as the water outlet 10D in the circumferential direction S, the lower end of the outer peripheral wall 10B is located on the upper side Z1 than the lower end of the inner peripheral wall 10A. The tank cleaning member 10 has a lower wall 10F that is installed between the lower end of the inner peripheral wall 10A and the lower end of the outer peripheral wall 10B. At the lower wall 10F at the same position as the water outlet 10D in the circumferential direction S, the outer edge portion 10FA on the radial outer side R1 and the inner edge portion 10FB on the radial inner side R2 extend horizontally in the radial direction R, but the intermediate portion 10FC between them is inclined so as to rise toward the radial outer side R1. The inner edge portion 10FB is formed in a circular ring shape that extends horizontally along the circumferential direction S. Each water outlet 10D is located above the water supply port 10C on the inner wall 10A, i.e., at a higher position Z1.

Figure 3 is a plan view of the tank cleaning member 10. In the upper surface portion 10EA of the upper wall 10E, in the region of the radially inner side R2 near the inner edge 10EC, an arc-shaped water receiving port 10G is provided that penetrates the upper wall 10E in the vertical direction Z and extends along the circumferential direction S. A plurality of water receiving ports 10G of the same size (four in this embodiment) are provided and arranged at equal intervals in the circumferential direction S. The tank cleaning member 10 has a plurality of partitions 10H, one between each adjacent water receiving port 10G.

Figure 4 is a cross-sectional view taken along the line A-A in Figure 2. In this embodiment, four partitions 10H are provided, each of which is a plate extending in the radial direction R and is installed between the inner circumferential wall 10A and the outer circumferential wall 10B. The tank cleaning member 10 has an annular internal space 10I extending along the inner circumferential wall 10A, and the internal space 10I is divided by these partitions 10H into multiple water storage sections 10J of the same size. The same number of water storage sections 10J as the water receiving ports 10G are provided. The water storage sections 10J are disposed one by one directly below the water receiving ports 10G that are located at the same position in the circumferential direction S. In a plan view, the water receiving ports 10G and the water storage section 10J directly below them have the same size (see Figure 3).

The tank cleaning member 10 has an annular rib 10K disposed between the inner peripheral wall 10A and the outer peripheral wall 10B and extending in the circumferential direction S. A water storage section 10J is defined between the inner peripheral wall 10A and the rib 10K. At the same positions in the rib 10K in the circumferential direction S as the water outlets 10D of the outer peripheral wall 10B, relay ports 10L that are wider in the circumferential direction S than the water outlets 10D are provided by penetrating the rib 10K in the radial direction R.

The tank cleaning member 10 has a pair of ribs 10M that connect the water outlet 10D and the relay port 10L that are at the same position in the circumferential direction S. The ends of the pair of ribs 10M on the radially outer side R1 are connected to both ends of the water outlet 10D in the circumferential direction S, one each. The ends of the pair of ribs 10M on the radially inner side R2 are connected to both ends of the relay port 10L in the circumferential direction S, one each. One guide path 10N is provided between the pair of ribs 10M. The same number of pairs of ribs 10M are provided as the water outlets 10D, so that the tank cleaning member 10 as a whole has the same number of guide paths 10N as the water outlets 10D, i.e. multiple paths 10N.

Each conduit 10N is connected to a water outlet 10D and a water storage section 10J at the same position in the circumferential direction S. In each conduit 10N, the area on the water outlet 10D side is called the downstream area 10NA, and the area on the water storage section 10J side is called the upstream area 10NB. In each conduit 10N, the spacing in the circumferential direction S between a pair of ribs 10M narrows as it moves toward the radially outward R1, so the conduit 10N narrows in the circumferential direction S as it moves toward the radially outward R1. The conduit 10N is sandwiched between the upper wall 10E and the lower wall 10F in the vertical direction Z, but in the lower wall 10F, the outer edge portion 10FA is positioned higher than the inner edge portion 10FB, so the conduit 10N narrows in the vertical direction Z as it moves toward the radially outward R1 (see FIG. 2). As a result, in each conduit 10N, the flow area in the downstream region 10NA is equal to or smaller than the flow area in the upstream region 10NB. The flow area is the cross-sectional area of the conduit 10N when cut along the circumferential direction S or the tangential direction T.

Figure 5 is an enlarged view of the main parts in Figure 1. In the tank cleaning member 10 fixed to the inner tank 4, each water outlet 10D is located at a higher position than the overflow port 3D of the outer tank 3, and each water receiving port 10G is located at the same position in the radial direction R as the relay port 3H of the annular wall 3C of the outer tank 3 and lower than the relay port 3H. Therefore, any one of the water receiving ports 10G is always located directly below the relay port 3H. The water supply port 10C provided on the inner wall 10A of the tank cleaning member 10 faces the inside of the inner tank 4 from the radial outside R1 and the upper side Z1. Note that the space surrounded by the balancer 9 and the space surrounded by the tank cleaning member 10 may be considered as the entrance/exit 4C of the inner tank 4.

The washing machine 1 further includes a control unit 30, which is configured, for example, by a microcomputer and is built into the housing 2. The control unit 30 includes a CPU, memories such as ROM and RAM, and a timer for measuring time. The motor 6, the transmission mechanism 7, the display operation unit 12, the water supply valve 18, and the drain valve 19 are each electrically connected to the control unit 30. The control unit 30 controls the duty ratio of the voltage applied to the motor 6 to control the motor 6 so that it rotates at a desired rotation speed. The control unit 30 controls the transmission mechanism 7 to switch the transmission destination of the torque of the motor 6 to one or both of the support shaft 21 and the rotating shaft 22. When the user operates the display operation unit 12 to select operating conditions, etc., the control unit 30 accepts the selection. The control unit 30 controls the display of the display operation unit 12. The control unit 30 controls the opening and closing of the water supply valve 18 and the drain valve 19.

The control unit 30 executes a washing operation by controlling the operation of the motor 6, the transmission mechanism 7, the water supply valve 18, and the drain valve 19. The washing operation includes a washing process for washing the laundry in the inner tub 4, a rinsing process for rinsing the laundry in the inner tub 4 after the washing process, and a spin-drying process for rotating the inner tub 4 to spin-dry the laundry. The rinsing process may be executed multiple times, and the spin-drying process includes an intermediate spin-drying process executed during the washing operation, and a final spin-drying process executed at the end of the washing operation. The washing machine 1 may be a washer-dryer that also executes a drying process for drying the laundry Q after the final spin-drying process.

In the washing process, the control unit 30 opens the water supply valve 18 with the drain valve 19 closed. At this time, the motor 6 is stopped, so both the inner tub 4 and the rotor 5 are stationary. When the water supply valve 18 opens, water from the faucet falls from the water supply passage 17 into the detergent case 16 in the water supply unit 13, and then falls from the water conduit 16C to the relay port 3H of the outer tub 3, carrying the detergent in the detergent case 16 (see arrow P1).

The water that falls from the water supply unit 13 into the relay port 3H falls into one of the water receiving ports 10G located directly below the relay port 3H on the upper surface 10EA of the tub cleaning member 10, and after being received by the water receiving port 10G, falls through the water receiving port 10G into the water storage unit 10J (see arrow P2). The water in the water storage unit 10J falls into the inner tub 4, i.e., the washing tub 8, through the nearest water supply port 10C on the inner wall 10A of the tub cleaning member 10 (see arrow P3). This water supply process allows water to be supplied to the washing tub 8. All of the detergent in the detergent case 16 is supplied to the inner tub 4 by the water supply process.

After the water supply process, the control unit 30 switches the transmission mechanism 7 as necessary so that the torque of the motor 6 is transmitted to the rotor 5, and then drives the motor 6 to rotate the rotor 5. As a result, the laundry in the inner tub 4 is agitated and washed by the rotating rotor 5 as an agitation process. In addition, dirt on the laundry is broken down by the detergent dissolved in the water. When a predetermined agitation time has elapsed, the control unit 30 stops the motor 6 to end the agitation process, and as a drainage process, the drain valve 19 is opened to drain the water from the washing tub 8. This ends the washing process.

The rinsing process is substantially the same as the washing process, except that no detergent is present. Specifically, the control unit 30 uses a water supply process to fill the washing tub 8 with water, specifically tap water, and then executes an agitation process to agitate and rinse the laundry in the inner tub 4. After that, when a predetermined agitation time has elapsed, the control unit 30 executes a drainage process to end the rinsing process.

In the spin-drying process, the control unit 30 rotates the inner tub 4 at high speed with the drain valve 19 open. The laundry in the inner tub 4 is spin-dried by the centrifugal force generated by this high-speed rotation. Water that seeps out of the laundry during spin-drying is discharged outside the machine through the drain 14. However, the rotation conditions of the inner tub 4 may be different between the intermediate spin-drying process and the final spin-drying process, and in particular, the maximum rotation speed of the inner tub 4 in the final spin-drying process is higher than the maximum rotation speed of the inner tub 4 in the intermediate spin-drying process. Water may be present in the water storage section 10J of the tub cleaning member 10 while the inner tub 4 is rotating, and in this case, the tub cleaning member 10 may contribute to reducing vibration of the inner tub 4 during rotation, similar to the balancer 9.

Such a tub cleaning member 10 may be called a "top balancer" or may be considered as part of the balancer 9. At the end of the spin-drying process, the control unit 30 switches the transmission mechanism 7 to stop the motor 6 so that the torque of the motor 6 is not transmitted to the inner tub 4, causing the inner tub 4 to rotate by inertia. At the end of the spin-drying process, the control unit 30 closes the drain valve 19.

The control unit 30 executes a tub cleaning process to clean the washing tub 8, either as part of the washing operation or as a process independent of the washing operation. If the tub cleaning process is executed as part of the washing operation, it is preferable to execute it after the final spin-drying process. The tub cleaning process will be described with reference to the flowchart in FIG. 6. During the tub cleaning process, the drain valve 19 is always open. Prior to the start of the tub cleaning process, the control unit 30 switches the transmission mechanism 7 so that the torque of the motor 6 is transmitted to the inner tub 4. If the transmission mechanism 7 has already been switched, the process of switching the transmission mechanism 7 is omitted.

At the beginning of the tank cleaning process, the control unit 30 opens the water supply valve 18 (step S1). Then, the control unit 30 operates the motor 6 to rotate the inner tank 4 at a low speed (step S2). An example of the rotation speed of the motor 6 at this time is 50 rpm or less. At this time, the inner tank 4 may rotate continuously at a constant rotation speed, or may rotate intermittently by repeatedly increasing and decreasing the rotation speed.

As the water is supplied while the inner tank 4 rotates, the water that has fallen from the water supply section 13 to the relay port 3H falls through each of the water receiving ports 10G on the upper surface 10EA of the tank cleaning member 10, which rotates slowly together with the inner tank 4 (see arrow P2 in FIG. 5), and is stored in the water storage section 10J directly below each water receiving port 10G. The centrifugal force caused by the slow rotation of the inner tank 4 moves the water in each water storage section 10J away from the water supply port 10C radially outward R1, so that the water does not fall from the water supply port 10C into the inner tank 4 and remains stored in the water storage section 10J. The process of step S2 may be performed simultaneously with the process of step S1, or may be performed prior to the process of step S1.

As described above, the internal space 10I of the tub cleaning member 10 is divided into multiple water storage sections 10J by the partitions 10H, so that each water storage section 10J has a small capacity. This allows water to be quickly filled in each water storage section 10J, so preparations for cleaning the washing tub 8 can be completed quickly. Then, after filling all of the water storage sections 10J with water, the control section 30 closes the water supply valve 18 to stop the water supply while continuing to rotate the inner tub 4 at a low speed (step S3), and then increases the rotation speed of the motor 6 to, for example, 700 rpm to rotate the inner tub 4 at a steady speed (step S4).

Then, the water in each water storage section 10J of the tub cleaning member 10, which rotates at high speed together with the inner tub 4, flows through one of the conduits 10N and is guided to the water outlet 10D by the centrifugal force that increases with the high speed rotation, and is forcefully discharged from the water outlet 10D to the radially outward R1 (see arrow P4 in FIG. 5). Since each water outlet 10D is located at a higher position than the overflow outlet 3D, the water discharged from each water outlet 10D reaches the washing tub 8, especially the dirt on the inner circumferential surface of the circumferential wall 3A of the outer tub 3, which is at a higher position than the overflow outlet 3D, and removes this dirt. Therefore, the washing tub 8 can be effectively cleaned. Furthermore, the washing tub 8 can be kept clean even if the user does not use detergent or the like to clean the washing tub 8.

As described above, the water outlet 10D opens toward the radially outward side R1 or toward the tangential direction T relative to the circumferential direction S (see FIG. 4). This allows the water discharged from the water outlet 10D to spray dirt on the inner surface of the outer tub 3 that is located at a higher position than the overflow outlet 3D, effectively removing the dirt. In this way, the washing tub 8 can be cleaned even more effectively. In addition, water is discharged radially from the multiple water outlets 10D and sprayed onto the inner surface of the circumferential wall 3A of the outer tub 3, so that the entire area of the circumferential wall 3A in the circumferential direction S can be cleaned evenly.

Furthermore, since the flow area in the downstream region 10NA on the water outlet 10D side of the conduit 10N is equal to or less than the flow area in the upstream region 10NB on the water storage section 10J side of the conduit 10N, the water in the conduit 10N is forcefully discharged from the water outlet 10D and splashed onto dirt in the washing tub 8 that is at a higher position than the overflow outlet 3D. This effectively removes the dirt, and the washing tub 8 can be cleaned even more effectively. The water splashed onto the washing tub 8 from each water outlet 10D of the tub cleaning member 10 may be hypochlorous acid water or ozone water, which have a high cleaning effect.

When the high speed rotation of the inner tub 4 continues for a predetermined time, the water in the water storage section 10J will be depleted, and the control section 30 may stop the motor 6. The cycle of steps S1 to S4 may be repeated a predetermined number of times. Of course, the predetermined number of times may be just once. When this cycle has been performed the predetermined number of times (NO in step S5), the control section 30 ends the tub cleaning process. Note that any water remaining in each water storage section 10J in the tub cleaning member 10 is discharged from the water storage section 10J through the water supply port 10C, which also functions as a drain hole (see arrow P3 in Figure 5).

This invention is not limited to the embodiments described above, and various modifications are possible within the scope of the claims.

REFERENCE SIGNS LIST 1 washing machine 3 outer tub 3D overflow port 3F drain port 3G opening 4 inner tub 4C inlet/outlet 4D through hole 6 motor 8 washing tub 10 tub cleaning member 10B outer peripheral wall 10C water supply port 10D water outlet 10EA upper surface 10G water receiving port 10H partition 10I internal space 10N conduit 10NA downstream region 10NB upstream region 10J water storage section 13 water supply section 14 drainage channel 15 overflow channel J axis R radial direction R1 radially outward S circumferential direction T tangential direction Z2 lower side

Claims (5)

A drive unit that generates a torque;
a washing tub having an outer tub provided with a drain outlet, an overflow outlet located at a position higher than the drain outlet, and an opening located at a position higher than the overflow outlet, and for storing water; an inner tub provided with a through hole for passing water between the outer tub and the inner tub, and an inlet/outlet facing the opening from below, and disposed within the outer tub, laundry is put in and taken out through the opening and the inlet/outlet, and the inner tub rotates by receiving a torque from the drive unit;
A drainage channel connected to the drain outlet for discharging water from the washing tub;
An overflow channel connected to the overflow outlet and directing water in the washing tub from the overflow outlet to the drainage channel;
A water supply unit that supplies water into the washing tub;
The device includes a hollow tank cleaning member fixed to the inner tank, the hollow tank cleaning member having an upper surface portion provided with a water receiving port for receiving water from the water supply portion, an outer peripheral portion provided with a water outlet located at a position higher than the overflow port, a water storage portion for storing water that falls through the water receiving port, and a guide path for guiding the water in the water storage portion to the water outlet ,
The guide path extends along a straight line passing through the water storage section and the water outlet in a vertical cross section of the washing machine . The washing machine according to claim 1, wherein the water outlet opens radially outward from the rotation axis of the inner tub or in a tangential direction relative to the circumferential direction around the rotation axis. The washing machine according to claim 1 or 2, wherein the flow area of the conduit in the downstream region on the water outlet side is equal to or smaller than the flow area of the conduit in the upstream region on the water storage side. The washing machine according to any one of claims 1 to 3, wherein the tub cleaning member has a partition that divides the internal space of the tub cleaning member into a plurality of water storage sections. The washing machine according to any one of claims 1 to 4, wherein the tub cleaning member is provided with a water supply port through which water in the water storage section falls into the washing tub.

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