EP2103728B1

EP2103728B1 - Drum type washing machine

Info

Publication number: EP2103728B1
Application number: EP09150362A
Authority: EP
Inventors: Kenji c/o Panasonic Corporation Int. Property Rights Op. Comp. Terai; Shinji c/o Panasonic Corporation Int. Property Rights Op. Comp. Matsuoka; Tsuyoshi c/o Panasonic Corporation Int. Property Rights Op. Comp. Murao
Original assignee: Panasonic Corp
Current assignee: Panasonic Corp
Priority date: 2008-03-13
Filing date: 2009-01-12
Publication date: 2013-03-20
Anticipated expiration: 2029-01-12
Also published as: KR20090098673A; CN101532232A; CN201372374Y; EP2103728A3; CN101532232B; JP2009213801A; TWI367978B; JP4331243B1; TW201002902A; KR101066282B1; EP2103728A2

Description

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to a drum type washing machine having a rotary drum formed in a cylindrical shape in a water tank, for washing the laundry contained in the rotary drum by driving the rotary drum.

2. Background Art

Such drum type washing machine having a circulation function for circulating the water in the water tank by a circulation pump has been known.
For example, in Unexamined Japanese Patent Application Publication No. 11-276791 (patent document 1), one pump is used selectively in two situations. First, it is used as circulation pump in the washing process and rinsing process, and the rinsing water and washing water are circulated, and it is used for agitating the detergent and washing water to dissolve the detergent smoothly in a first half of washing process. Second it is used as discharge pump in dewatering and draining process. A filter case is provided in the middle of the suction side of the circulation pump in the circulation route, and lint and debris in the suction water are captured. Thus, lint does not get into the circulation pump.
In Unexamined Japanese Patent Application Publication No. 2005-58741 (patent document 2), the water in the water tank is circulated by the circulation pump, and staying of the detergent in a heater space or specific space is prevented. At the same time, the laundry is quickly heated before washing, and the washing efficiency is enhanced.
In Unexamined Japanese Patent Application Publication No. 2006-223572 (patent document 3), the circulation pump unit combining the circulation pump section and the filtering section for capturing lint and debris is installed on a platform at the bottom of the outer case of the washing machine. The circulation pump unit is mounted on the platform by way of an elastic cushion, propagation of vibration of pump motor to the platform is prevented. As a result, noise by resonance of vibration of pump motor and vibration of outer case is prevented.
In Unexamined Japanese Patent Application Publication No. 2006-239142 (patent document 4), the water in the water tank is added into the rotary drum, and injected around the heater for drying, and lint sticking around the heater can be removed.
However, these technologies about water circulation disclosed in patent documents 1 to 4 are commonly designed to inject the circulation water from the piping end into the rotary drum. As a result, the circulation water is injected only to local parts of the laundry in the rotary drum, and the circulation effect cannot be utilized sufficiently. In the technologies disclosed in patent documents 2 and 4, on the other hand, a special spray nozzle is used for injecting in wide area. But the special spray nozzle adds to the cost, and the pump pressure must be raised, and an extra cost is added. The technologies disclosed in patent documents 1, 3, 4 relate to a structure in which the piping of the water circulation system penetrates through the front end wall of the water tank to be opposite in the rotary drum, and the piping structure is further complicated and costly.
WO 2008/125974 A (state of the art according to article 54 (3) EPC is published after the present priority date and relates to a laundry washing machine. A front loading laundry washing machine comprises a washing tub, a laundry basket mounted in the tub, motor means to actuate the basket in rotation and a system for feeding liquid in the basket. The basket has a first and a second -end wall, between which a peripheral wall extends. The liquid feeding system comprises at least one inflow passage formed in a prevalently imperforated annular region of the peripheral wall of the basket and an inflow conduit having a delivery outlet facing toward the prevalently imperforated annular region. It is further provided a positioning system designed for bringing and/or maintaining the basket in a substantially predetermined angular position within the tub, in such a position the inflow passage being substantially aligned with the delivery outlet of the inflow conduit to receive therefrom a liquid flow for the purpose of loading of liquid in the basket.

SUMMARY OF THE INVENTION

The invention is defined by the subject-matter of the independent claim. The dependent claims are directed to advantageous embodiments.

ADVANTAGES OF THE INVENTION

Advantageously, it is provided a drum type washing machine simple in discharge structure for circulation of water in the water tank by a circulation pump into a rotary drum of circulation water by discharge side route from the circulation, pump.
Advantageously, it is provided a drum type washing machine having a rotary drum formed in a cylindrical shape with a bottom installed in a water tank so that the rotary shaft direction may be horizontal or inclined downward from the horizontal direction from the opened front side to the back side at the bottom, and capable of executing at least one of washing process and rinsing process by driving the rotary drum by a motor, and comprising a water circulation mechanism for circulating the water in the water tank by a circulation pump through a circulation route connected to the water tank, in which the water circulation mechanism has a passage for discharging the circulation water in the rotary drum provided between the front end wall reverse side of the water tank and the front end wall surface of the rotary drum.
In this configuration, only by connecting the circulation route to the front end wall of the water tank, the circulation route is linked to the passage formed between the front end walls of the water tank and rotary drum. Accordingly, every time the water circulation mechanism circulates by sucking the water in the water tank and returning to the water tank in the washing process and/or rinsing process by its circulation pump and circulation route, the circulation water is discharged into the rotary drum from an annular outlet formed in the inner circumferences of the both front end walls through this route without requiring any particular piping. The circulation water is discharged from the annular outlet between the inner circumferences of the front end walls through the passage between the front end walls of the water tank and rotary drum.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a sectional view of outline structure of a drum type washing machine in a preferred embodiment of the present invention.
FIG. 2 is a sectional view of water suction part and water discharge part of the drum type washing machine in the preferred embodiment.
FIG. 3 is a plan view of water suction part and water discharge part of the drum type washing machine in the preferred embodiment.
FIG. 4 is a perspective view of essential configuration of the drum type washing machine in the preferred embodiment.
FIG. 5A is a sectional view of circulation pump used in the drum type washing machine in the preferred embodiment.
FIG. 5B is a side view of circulation pump used in the drum type washing machine in the preferred embodiment.
FIG. 5C is a bottom view of circulation pump used in the drum type washing machine in the preferred embodiment.
FIG. 6 is a perspective view of filter of the drum type washing machine in the preferred embodiment.
FIG. 7 is a front view of filter mounting part of the drum type washing machine in the preferred embodiment.
FIG. 8 is a perspective view of front part of the drum type washing machine in the preferred embodiment.
FIG. 9A is a front view of duct for connecting between water circulation route and discharge side route of the drum type washing machine in the preferred embodiment.
FIG. 9B is a lateral sectional view of duct for connecting between water circulation route and discharge side route of the drum type washing machine in the preferred embodiment.
FIG. 9C is a longitudinal sectional view of duct for connecting between water circulation route and discharge side route of the drum type washing machine in the preferred embodiment.

DETAILED DESCRIPTION OF THE INVENTION

The drum type washing machine in a preferred embodiment of the present invention is specifically described below while referring to FIG. 1 to FIG. 9C. The following explanation is a specific example of the present invention, and is not intended to limit the scope of the claims.
FIG. 1 is a sectional view of outline structure of a drum type washing machine in a preferred embodiment of the present invention. In FIG. 1, the drum type washing machine of the preferred embodiment is similar to the prior art and operates according to the mode setting or control program, and has functions for executing at least the washing process, rinsing process, dewatering process, and drying process by controlling automatically motor 6, water feed mechanism 7, discharge mechanism 8, and drying mechanism 9. However, drying mechanism 9 is not always required.
In addition, the preferred embodiment also has functions for circulating the water in water tank 3 by water circulation system 16 for encouraging dissolving of detergent, preventing uneven dissolving, and enhancing the washing and rinsing functions, as required, in the washing preparation process, washing process, and rinsing process. Water feed mechanism 7 is a mechanism disposed from an external water faucet to water tank 3. Water feed mechanism 7 is designed to supply water appropriately when required by opening or closing of a solenoid valve as indicated by solid line arrow. By making use of water supply, the detergent in a detergent container is properly charged into water tank 3.
Discharge mechanism 8 is disposed from water tank 3 to external drain. Discharge mechanism 8 is designed to discharge water as indicated by single dot chain line arrow when required, at the end of washing process or at the end of rinsing process, by opening or closing discharge valve 19. Drying mechanism 9 is disposed so as to circulate between blower 12 and water tank 3.
Drying mechanism 9 has a drying circulation route for circulating the air in water tank 3 and rotary drum 4 by blower 12 as indicated by broken line arrow. The drying circulation route contains filter 15 for capturing and removing lint and dust in the feed air from water tank 3 and rotary drum 4. The drying circulation route also contains dehumidifying part 10 for removing moisture from the filtered air. The drying circulation route contains further a heating part 11 for heating the dehumidified air to produce dry hot air. Blower 12 is disposed at the downstream side of heating part 11 so as to avoid effects of moisture. Dehumidifying part 10 and heating part 11 are specifically an evaporator and a condenser for exchanging heat with the circulation air by a refrigerant circulated by compressor 17, and thereby air-conditioner 18 is composed. However, drying mechanism 9 is not limited to this structure alone.
Water circulation system 16 repeats the cycle of operation by sucking the water in water tank 3 by circulation pump 20, and returning into water tank 3.
Operation courses, modes and functions are selected by input from operation panel 21 provided in the front upper part of washing machine main body 2. Control mechanism 22 indicates the input information in the display area of operation panel 21 to inform the user. When operation start is set by the input setting unit on operation panel 21, data is entered from water level detector for detecting the water level in water tank 3, and driving is started. As a result, operation of discharge valve, water feed valve and others is controlled, and operations of washing, dewatering, and drying are started.
In rotary drum 4, motor 6 installed in water tank 3 is directly coupled on rotary shaft 4a, and is installed together with water tank 3 from the opening side toward the bottom side in the rotary shaft direction at an inclination of angle θ =20±10 degrees from the horizontal direction. As compared with installation in the horizontal direction, if rotary drum 4 is installed at same height, the opening of water tank 3 and rotary drum 4 is inclined upward, and the user can easily put in or take out the laundry without bowing or changing the body posture. In particular, according to the experience of the inventors, the inclination angle of 20±10 is preferred because the laundry can be easily put in or taken out, in spite of the height difference, by children (excluding infants), adults or wheelchair users. Besides, if the volume of water collected in rotary drum 4 is not enough to reach the back side, a deep water pool is obtained. Water tank 3 is disposed around the rotary drum 4 at similar inclination so that the water may be applied efficiently on the laundry in rotary drum 4. A door 5 is provided in washing machine main body 2, and opening 13 of water tank 3 may be opened or closed through seal member 14 fitted at its opening edge.
Rotary drum 4 is driven continuously at a high rotating speed of, for example, 1000 rpm in the dewatering process. Accordingly, the laundry is entangled, twisted or creased in the washing process or rinsing process, and is stuck in this state to the inner surface of rotary drum 4. As a result, it is hard to take out laundry and it takes time in the process. It is also hard to straighten the twisted and creased laundry.
To solve this problem, in the preferred embodiment, the washing process, or the washing process and the rinsing process are controlled in two modes as explained below in order to suppress occurrence of entangling or twisting, and suppress creasing while enhancing the mechanical force. First is the normal and reverse pivot rotation drive mode in which quick normal pivot rotation and quick reverse pivot rotation are repeated alternately in an angle range of rotary drum 4 exceeding 90 degrees to less than 180 degrees. Second is the normal and reverse continuous rotation drive mode in which rotary drum 4 is rotated continuously, and alternately in normal and reverse direction at a rotating speed allowing the laundry lifted by rotation of rotary drum 4 to fall from a height exceeding its own weight. In the washing process, or in the washing process and rinsing process, the normal and reverse pivot rotation drive mode and the normal and reverse continuous rotation drive mode are executed alternately. Thus, by such quick pivot rotation and sudden braking in an angle range of rotary drum 4 exceeding 90 degrees to less than 180 degrees, the laundry is lifted above the maximum limit of 90 degrees to less than 180 degrees. Further, by sudden braking in the final stage of lifting of the laundry, the laundry is stopped, and is peeled off from rotary drum 4 by its inertia and own weight, and is securely dropped to the right or left opposite side of the lifting side by the own weight. Therefore, on the laundry swollen by sufficient water and likely to relax and slip, a strong beating action is applied, and mechanical force acts on the laundry, and the cleaning performance is enhanced. The normal and reverse pivot rotation drive mode is also realized by alternately repeating the pivot rotation drive between quick normal pivot rotation in normal direction and quick normal pivot rotation in reverse direction. As a result, by normal and reverse alternate quick pivot rotation drive, the lifting position and the dropping position of the laundry can be exchanged alternately right and left in every time of pivot rotation drive. Therefore, the bearing action is further enhanced while suppressing entangling of the laundry, and the number of times of applying mechanical force to the laundry is increased, and the cleaning performance is reinforced. Besides, by the strong beating action, mutual entangling of the laundry can be suppressed in the repeated washing and rinsing processes. Thus, the effective beating and washing in the normal and reverse pivot rotation mode can be executed continuously, and the washing effect and the rinsing effect may be enhanced.
By the normal and reverse pivot rotation drive mode only, although entangling, twisting and creasing of the laundry may be suppressed, the laundry is hardly exchanged in the upper and lower positions, and the laundry in the bottom of rotary drum 4 is hardly moved, and the washing effect tends to be uneven. By combining together with the normal and reverse continuous rotation drive mode, the laundry is exchanged in the upper and lower positions. That is, in the normal and reverse continuous rotation drive mode, entangling, twisting and creasing of the laundry is lessened, and in the normal and reverse pivot rotation drive mode, uneven application of mechanical force to the laundry is lessened. Therefore, by the both modes, two different behaviors can be applied to the laundry in the washing and rinsing process. More specifically, the normal and reverse pivot rotation drive mode is effective to apply a firm hand-rubbing behavior while suppressing entangling, twisting and creasing of the laundry. The normal and reverse continuous rotation drive mode is effective to apply uniform and strong cleaning behavior while suppressing creasing by moving the laundry continuously and broadly.
In the drying process, in particular, the normal and reverse pivot rotation drive mode is effective for straightening the creased laundry after dewatering, and improving the finishing quality, contributing much to saving of labor in the finishing process. However, the laundry in the drying process is light in weight and hardly sticks to the inner surface of rotary drum 4, and hence the rotation angle of rotary drum 4 is preferably set at over 90 degrees to less than 200 degrees.
The maximum rotating speed of rotary drum 4 in the normal and reverse continuous rotation drive mode may be 45±5 rpm as usual, and the maximum rotating speed of rotary drum 4 in the normal and reverse pivot rotation drive mode is preferably 40 rpm or higher in the rinsing process, or 50 rpm or higher after dewatering.
Incidentally, as in the prior art, when circulation pump 20 for circulating the water in water tank 3 is mounted on bed plate 2a at the bottom of washing machine main body 2, setting of water circulation route for linking circulation pump 20 and water tank 3 is limited. That is, between circulation pump 20 at fixed side fixed to bed plate 2a and water tank 3 at vibration side, the distance between the connection positions and the position deflection are changed. To absorb such changes, it is required to link by using elastic and flexible hoses or the like. As a result, the hose may deteriorate early due to repeated vibrations or vibratory expansion and shrinkage, and water leak may occur.
In the preferred embodiment, therefore, circulation pump 20 for circulating the water in water tank 3 through water circulation route 31 is provided on water tank 3. Filter 32 for filtering the circulating water is provided in water suction part 33 for sucking water when circulating water in water tank 3, as shown in FIG. 2 and FIG. 3. FIG. 2 is a sectional view of water suction part and water discharge part of the drum type washing machine in the preferred embodiment. FIG. 3 is a plan view of water suction part and water discharge part of the drum type washing machine in the preferred embodiment.
Thus, when circulation pump 20 is installed in water tank 3, water circulation route 31 for connecting and linking between them is installed in water tank 3 together with circulation pump 20. Therefore, in spite of vibration of water tank 3, the distance between connection positions is not changed, or the position deflection does not occur. Hence, flexible or elastic property is not needed in water circulation route 31 between circulation pump 20 and water tank 3. Water circulation route 31 is required only to circulate water between water tank 3 and circulation pump 20 disposed on water tank 3, and the water in water tank 3 can be circulated by a short and durable piping structure. What is more, circulation pump 20 is not source of vibration for increasing the vibration having effects on the water tank when driving accompanied by biasing of the laundry in rotary drum 4, and the vibration control action for the portion of its weight may be applied to water tank 3.
Filter 32 is exposed and provided, facing the inside of water tank 3 in water suction part 33 from water tank 3 in water circulation route 31. Therefore, lint is prevented from entering the suction side route 31a of water circulation route 31 or circulation pump 20, and it is maintenance-free.
Thus, since both circulation pump 20 and water circulation route 31 is disposed on water tank 3, between the connection positions of circulation pump 20 and water circulation route 31, and between the connection positions of water tank 3 and water circulation route 31, changes of distance or position deflection due to vibration of water tank 3 can be avoided. Moreover, since water circulation route 31 is short and simple in piping structure, and flexible and elastic property is not needed, and any material excellent in vibration resistance can be used, specifically resin formed member may be used. Therefore, water circulation route 31 may be formed in simple, less bulky, less costly and durable structure, and the water in water tank 3 can be circulated when necessary, and the function of the washing machine may be enhanced. Besides, circulation pump 20 is not a significant vibration source for water tank 3, and can suppress increase of vibration of water tank 3 by vibration control action by the own weight, and silent operation and long life will be assured. It is hence preferred to be installed in a lower part in peripheral direction and axial line direction, being in favorable weight balance water tank 3. Further, filter 32 is positioned at water suction part 33 from water tank 3 of water circulation route 31, and thereby prevents lint from invading not only into circulation pump 20 but also into water suction side route 31a of water circulation route 31. Accordingly, lint is prevented from being hooked, collected or caught in circulation pump 20 in suction side route 31a, and clogging, damage or breakage of water circulation system 16 my be avoided. Therefore, the circulation operation may be assured safely and stably for a long time without requiring any particular maintenance against lint.
FIG. 4 is a perspective view of essential configuration of the drum type washing machine in the preferred embodiment. FIG. 5A to FIG. 5C are sectional view, side view, and bottom view of circulation pump used in the drum type washing machine in the preferred embodiment. Circulation pump 20 is, as shown in FIG. 4, fixed to bottom 3b of water tank 3 by fitting bolt 34 from beneath. Discharge side route 31b of water circulation route 31 from circulation pump 20 is directed ahead of washing machine main body 2 at the position of opening 13 of water tank 3, and is extended at an upward inclination of 20 degrees or more in the horizontal direction as shown in FIG. 1 to FIG. 4. More specifically, as shown in FIG. 5A to FIG. 5C, circulation pump 20 has resin-made pump casing 20b containing impeller 20a fitted integrally at bearing barrier wall 20dl at the front end of metal-made motor casing 20d of circulation motor 20c at the opening end side. Impeller 20a is directly coupled to motor shaft 20e, and it is fitted to resin-made fitting seat 35. Fitting seat 35 has C-shaped fitting pieces 35a at three peripheral positions (FIG. 5C). These fitting pieces 35a are fitted, from bottom 3b of water tank 3, to boss parts 3c protruding downward as shown in FIG. 4, and bolts 34 are driven into boss parts 3c. Thus, circulation pump 20 can be installed from beneath at bottom 3b of water tank 3, and the axial line of circulation pump 20 is in longitudinal direction, and does not disturb if circulation motor 20c is positioned at the upper side of pump casing 20b.
Thus, circulation pump 20 maybe easily detached from beneath water tank 3 at the time of maintenance. Discharge side route 31b from circulation pump 20 located at lower level than bottom 3b of water tank 3 at the rear side of washing machine main body 2 is realized in a piping of shortest length along the inclination or cylindrical shape of rotary drum 4 of water tank 3. That is, complicated structure is not needed for extending at an upward inclination of 20 degrees or more from horizontal direction toward the front part of washing machine main body 2. Circulation pump 20 sucks the water in water tank 3 through suction side route 31a, sends into discharge side route 31b, and discharges into water tank 3. At this time, inclined discharge side route 31b makes smooth air ventilation from pump casing 20b into discharge side route 31b. Hence, circulation pump 20 does not include air into suction water within pump casing 20b, and so-called air inclusion phenomenon is prevented. In the event of accident, maintenance of circulation pump 20 is easy. When the inclination angle of rotary drum 4 is 20±10 degrees, discharge side route 31b inclined upward by 20 degrees or more may exceed the condition setting of inclination angle of rotary drum 4. However, when the curvature shape of cylindrical surface in peripheral direction of water tank 3 is combined and utilized, a shortest piping not remote from water tank 3 may be realized.
Circulation pump 20 is inclined according to the slope of water tank 3 as shown in FIG. 2, but from the lower part of pump casing 20b having the axial line directed longitudinally, specifically from suction port 20f of L-shape integrally formed in the lower part, water is sucked. Then, from the peripheral wall of water tank 3, specifically through discharge port 20g (FIG. 4) formed integrally in the tangential direction, water is discharged. Accordingly, pump casing 20b and lowest part 31c of water circulation route 31 are located at higher positions than discharge valve 19 provided in discharge route 8a of discharge system 8 for discharging the water in water tank 3 to outside as shown in FIG. 2, and communicate at height position lower than the level of upstream of discharge valve 19 in discharge route 8a. That is, pump casing 20b and lowest part 31c of water circulation route 31 are connected to the upstream position of discharge valve 19 in discharge route 8a by extending at the same level or downward. Therefore, when discharge valve 19 opens, the water in pump casing 20b and water circulation route 31 flows spontaneously and smoothly into discharge route 8a from common lowest part 31c, which is very convenient.
As a result, pump casing 20b and lowest part 31c of water circulation route 31 are the locations of spontaneous flow of residual water in circulation pump 20 of discharge route 8a. Discharge route 8a communicates at height position lower than the level of the upstream of discharge valve 19. Therefore, when discharge valve 19 opens and water is discharged, the remaining water in water circulation route 8a and circulation pump 20 is discharged spontaneously through discharge route 8a. Therefore, water circulation route 31 allows to discharge remaining water in circulation pump 20 and other inside parts, together with the discharge water from water tank 3, and any particular discharge mechanism or discharge control is not needed.
Discharge route 8a and water circulation route 31, as shown in FIG. 2, commonly form and possess water receiving case 37 for receiving water from discharge port 36 and water suction part 33 connected to discharge route 8a of water tank 3. Water receiving case 37 includes suction piping region 37a to circulation pump 20 side, and discharge piping region 37b to discharge route 8a side. Accordingly, suction from water suction part 33 and discharge from discharge port 36 of water tank 3 are received in suction piping region 37a and discharge piping region 37b formed in one water receiving case 37, and the water receiving structure and seal structure are simplified. Suction to be received in suction piping region 37a corresponds to suction to circulation pump 20 through suction route 31. Discharge to be received in discharge piping region 37b corresponds to discharge through discharge route 8a. In such corresponding relation, when discharging, water receiving case 37 receives the remaining water from water circulation route 31 and circulation pump 20, and discharges spontaneously into discharge route 8a by way of discharge piping region 37b. That is, suction from water suction part 33 of water tank 3, and discharge from discharge port 36 are executed in suction piping region 37a and discharge piping region 37b formed in one water receiving case 37 formed integrally. Therefore, by the water receiving structure and the seal structure of simple configuration, low cost, and low maintenance, suction to circulation pump 20 through suction piping region 37a and discharge through discharge piping region 37b can be executed. What is more, when discharging, the remaining water in water circulation route 31 and circulation pump 20 can be spontaneously discharged into discharge route 8a by way of discharge piping region 37b, and any particular residual water treatment is not needed.
For discharging, in the preferred embodiment, in water receiving case 37, as shown in FIG. 2, suction piping region 37a and discharge piping region 37b communicate with each other through communication hole 37d provided in the position corresponding to lowest part 31e of barrier ribs 37c between them. Communication hole 37d is provided with check valve 38 for checking counter-flow from discharge piping region 37b side to suction piping region 37a side. By the check function of check valve 38 to prevent counter-flow from discharge piping region 37b side to suction piping region 87a side, when sucking into circulation pump 20 from water suction part 33 through filter 32, suction piping region 37a and suction side route 31a, water containing lint from discharge piping region 37b will not flow into suction piping region 37a side. Therefore, the water in water tank 3 can be circulated favorably by circulation pump 20. Moreover, when water is discharged from discharge route 8a through discharge piping 37b by opening discharge valve 19, the residual water in water circulation route 31 and pump casing 20 opens check valve 38 of communication hole 37d, and flows into discharge piping region 37b side, and hence spontaneous discharge is not disturbed. What is more, the check function of check valve 19 from discharge piping region 37b side to suction piping region 37a side does not require any special mechanism.
Not limited to the preferred embodiment, water receiving case 37 may have suction piping region 37a and discharge piping region 37b communicating with each other in a specified range of barrier rib 37c, specifically in an area larger than communication hole 37d, and a filter not shown may be disposed at the communicating position, or an integrally formed strainer may be provided. As a result, the check valve at the communicating position of suction piping region 37a and discharge piping region 37b may be omitted. Hence, the suction action from circulation pump 20 may be applied not only to suction piping region 37a but also to discharge piping region 37b through the communicating position. Since discharge valve 19 is closed, the water does not flow over the downstream side of discharge valve 19 of discharge route. Therefore, in addition to the suction from water sucking part 33 through filter 32 and suction piping region 37a, suction through discharge port 36, discharge piping region 37b and filter and strainer at communicating position can be also executed in parallel, and suction resistance can be lowered without allowing invasion of lint. Moreover, when water is discharged from discharge route 8a through discharge piping region 37b by opening discharge valve 19, the residual water in water circulation route 31 and pump casing 20 flows into discharge piping region 37b side through the filter and strainer at the communicating position, and hence spontaneous discharge is not disturbed. What is more, the residual water in water circulation route 31 and pump casing 20b does not contain lint, and lint is filtered, and are not captured in suction piping region 37a, and spontaneous discharge to discharge piping region 37b side is not disturbed. To the contrary, at the time of suction to discharge piping region 37b side of filter or strainer, lint will not flow into the discharge, or if contained, the water flows into discharge piping region 37b side in back washing process, and is discharged spontaneously. Accordingly, any particular maintenance is not needed for removing lint contained in residual water or in suction side route 31a or discharge route 8a.
Water suction part 33 and filer 32 are located, as shown in FIG. 2, at higher position than discharge port 36 to which discharge route 8a connected in water tank 3, and at a position less the lowest water level in water circulation mode, thereby not disturbing the flow of water of water tank 3 into discharge port 36. In the preferred embodiment, filter 32 is fitted to water suction part 33 opened immediately above discharge port 36 opened in lowest position 3d at the peripheral wall of water tank 3. That is, a nearly flat top surface is positioned slightly higher than the peripheral wall inside of water tank 3, so as not to block the flow of water into discharge port 36. For this purpose, filter 32 may be formed, in a plan view, in a circular shape or elliptical shape, bulging upward like a dome or a hill. However, it is preferred to limit the height of the lowest position, so that the filter surface may receive the washing flow action as mentioned below, by the flow of water at the time of discharge, even by the discharge from the lowest position.
Thus, in the preferred embodiment, water suction part 33 and filer 32 are located at higher position than discharge port 36 of water tank 3, and at a lower position than the lowest water level in water circulation mode, thereby not disturbing the flow of water of water tank 3 into discharge port 36. Accordingly, filter 32 is not separated from water tank 3 while filtering. Hence, lint may be sticking to the surface of filter 32, but it may be washed away as being exposed to the discharge flow when reducing the water volume in water tank 3 or by exposure to the water flow toward discharge port 36. As a result, the lint is discharged together with discharge, along with lint sticking to the filter or strainer in discharge piping region 37b, and lint is not collected in the filter part on every occasion of circulation operation. Hence, any particular maintenance is not required for the lint remaining in the residual water or in the suction side route 31a or discharge route 8a.
FIG. 6 is a perspective view of filter of the drum type washing machine in the preferred embodiment. FIG. 7 is a front view of filter mounting part of the drum type washing machine in the preferred embodiment. Filter 32 of water suction part 33 is, as shown in FIG. 2 and FIG. 6, opened in water suction part 33, and forms larger covering space 41 than suction port 39 connected to suction side route 31a, and covers suction port 39. Accordingly, filter 32 cooperates with covering space 41 of its inside, and assures a wider water passing area than suction port 39, and the entire water passing area communicates with suction port 39 through covering space 41, and the water passing area is large than suction port 39, so that clogging in water passing process is suppressed. At the same time, together with the washing flow caused in the water tank, pressure loss due to clogging is suppressed, and it is easier to assure a specified flow rate in circulation. For this purpose, it is preferred to set the total opening area of filter 32 of water suction part 33 larger than the opening area of suction port 39. As a result, in the water passing area larger than suction port 39 of filter 32, a total opening area larger than the opening area of suction port 39 is assured, clogging is prevented, and water passing resistance is further decreased. Therefore, the water passing area larger than suction port 39 of filter 32 is effectively utilized so s to assure a larger total opening area than the opening area of suction port 39, and clogging is prevented, and pressure loss is further decreased.
Herein, as disclosed in patent document 3, if the filter outlet is positioned at the front side of washing machine main body 2, the filtering mounting part of the washing machine may be accidentally touched by child's play or careless user. In the preferred embodiment, by contrast, filter 32 is provided or exposed in water tank 3, but may be easily detached from outside of water tank 3. Therefore, filter 32 is installed in washing machine main body 2 at a position not touched accidentally. On the other hand, incidentally, it may be detached or attached not in inside covered by rotary drum 4 at the corresponding opening position of washing machine main body 2, that is, outside of water tank 3 without being disturbed from others. Therefore, filer 32 is not usually touched accidentally, but may be detached easily without external intervention in case of maintenance or servicing.
Accordingly, filter 32 is detached or attached by sliding back and force from the front side of water tank 3 as shown in FIG. 2, FIG. 3, FIG. 4, or FIG. 6. Accordingly, filter 32 is fitted to the inner side of water tank 3, and this fitting position is easy for opening washing machine main body 2, and it is not attached or detached from the front side of water tank 3 accessible by hand. That is, by longitudinal sliding easy to handle, it is possible to attach or detach directly in the passing region of forming part of covering space 41 at the rear side of filter 32. Besides, the portion facing the inside of water tank 3 of filter 32 is formed nearly in a flat shape at least in the longitudinal direction as in the preferred embodiment, and the filter is formed in a flat shape as shown in FIG. 6, and can be attached and detached in a small space.
Filter 32 can be attached or detached through filter detaching port 42 directed to the front part on the outer circumference of water tank 3. At the reverse side of attached filter 32, water circulation route 31 is formed, or specifically, covering space 41 is formed as filter compartment communicating with suction side route 31a. Thus, the forming part of covering space 41 as filter compartment has filter detaching port 42 directed to the front part on the outer circumference of water tank 3. Hence, for sliding filter 32 back and forth for attaching or detaching, from filter detaching port 42 to filter fitting position, a short stroke nearly equal to filtering region is realized. Filter 32, at fitting position facing the inside of water tank 3, filters the water in water tank 3 by passing to covering space 41 side as filter compartment, and passes into water circulation route 31, specifically, suction side route 31a. Incidentally, in order to form filter detaching port 42 of the forming part of covering space 41 as the filter compartment as an opening toward the front part on the outer circumference of water tank 3, as shown in the drawing, it is preferred to open by forming a step part 3f toward the front part on the outer circumference of water tank 3. More specifically, as shown in FIG. 2, FIG. 3, water suction part 33 is provided in the bottom of water collecting part 3e sinking downward from bottom 3b on the peripheral wall of water tank 3 together with discharge port 36. Covering space 41 is opened to the bottom of water collecting part 3e. A recess for opening suction port 39 is provided in the bottom of covering space 41. Filter fitting part 42 is opened in the portion forming downward step 3f toward the front part of washing machine main body 2 of water collecting part 34 positioned around bottom 3b of water tank 3 (FIG. 2 to FIG. 4). In the front lower part of washing machine main body 2, detachable cover 43 is fixed by screw 44. In the event of trouble, as shown in FIG. 8, filter 32 can be detached by loosening screw 44 of detachable cover 43, and the fitting part of filter 32 is exposed beneath the front part of washing machine main body 2. Therefore, as shown in FIG. 8, if there is obstacle such as control unit 45 in washing machine main body 2, by slightly loosening screw 46, by loosening so as to prevent tilting, and the wiring of control unit 45 may be drawn and tilted forward, so that filter 32 may be easily detached, and it may be easily cleaned, repaired or replaced, and the maintenance is easy.
Herein, the forming part of covering space 41 as filter compartment includes filter detaching port 42 directed to the front part, opening 41a exposed so that fitted filter 32 may face the inside of water tank 3, and bottom 41b covering other than covering space 41. Water circulation route 31 communicates with bottom 41b. Thus, the forming part of covering space 41 is formed like a simple box, and is easily formed integrally to the peripheral wall of water tank 3 by simple blanking form through filter detaching port 42, and no particular member is needed in forming. Therefore, the detachable installation structure of filter 32 does not add to the cost.
As shown in FIG. 2, heater 71 for heating the circulation water for enhancing the washing and rinsing effect is contained in the forming part of covering space 41 as filter compartment. Heater 71 shares filter detaching port 42, and may be detached or attached same as filter 32. Alternatively, heater 71 may be detached or attached from outside of water tank 3 by forming an exclusive heater detaching port in addition to filter detaching port 42. Or, as shown in FIG. 2, heater 71. may be disposed in recess 32d at the back side of filer 32, and may be detached or attached simultaneously with filter 32. It requires, however, additional measure of forming an electrical connecting part having an insulating structure from the power feed part provided at the outside of water tank 3 at the fitting position of filter 32.
More specifically, in the preferred embodiment, filter 32 includes, as shown in FIG. 2, FIG. 6, FIG. 7, inserting part 32a for inserting into covering space 41 through detaching port 42, and range part 32b for sealing detaching port 42 upon completion of insertion into covering space 41. Flange part 32b has seal member 47 for sealing detaching port 42 by approaching or contacting the opening front part of detaching port 42 when filler 32 is inserted into covering space 42. Further, in inserting part 32a, filter 32 is drilled and forming by a forming die, and gripping part 32c is formed at the front side of flange part 32b so as to be detached and attached easily.
In this configuration, filter detaching port 42 is sealed easily and securely by the action of fitting pressure or mounting pressure on seal member 47 without any particular operation with filter 32 to be mounted, and water leak due to filter detaching and attaching structure may be prevented.
Further, to prevent accidental loosening of insertion or loosening of seal due to vibration of water tank 3 or the like, flange part 32b is provided at the side of water tank 3, and mounting hole 49 is provided for screwing with screw 48 as shown in FIG. 2. Inserting part 32a has protruding part 32a1 for discharging as specified or exposing as specified in water tank 3, in the fitting state of filter 32 in opening 41a of covering space 41 of water tank 3 in insertion complete state. Inserting part 32a has further positioning flange 32a2 in wedge shape in side view around protruding part 32a1, excluding flange part 32b, lower than protruding part 32a1 and at inserting side, that is, toward the back side of washing machine main body 2. Flange part 32a2 is guided by guide groove 41b of wedge shape in side view formed at the lower side of opening edge of opening 41a of covering space 41 of water tank 3. As a result, inserting part 32a is easily and securely inserted into specified insertion complete position, and is fixed in specified protruding state or exposed state.
Herein, FIG. 9A to FIG. 9C are a front view, a lateral sectional view, and a longitudinal sectional view of duct for connecting between water circulation route and discharge side route of the drum type washing machine in the preferred embodiment. Discharge side route 31b of water circulation route 31 is connected from outside to injection port 51, provided in the lowest part of front end wall 3h around opening 13 of water tank 3 as shown in FIG. 1, FIG. 4, FIG. 9A to FIG. 9C. Hence, between the reverse side of front end wall 3h of water tank 3 and the surface of front end wall 4b of corresponding rotary drum 4, circulation water from discharge side route 31b is injected, and is discharged into rotary drum 4 through passage 52 formed between them. In such configuration, injection port 51 of water from discharge side route 31b is located at a position not contacting with the laundry in rotary drum 4, and the laundry is not hooked to disturb the behavior in washing, rinsing or drying process, or the laundry is not damaged or torn. At the same time, since passage 52 is formed between front end wall 3h of water tank 3 and front end wall 4b of rotary drum 4, any particular component is not needed, and only seal member 56 is used, and risk of water leak is reduced in simple structure and at low cost. The injection effect of circulation water is enhanced by combination of behavior of laundry exchanged in upper and lower positions by normal and reverse continuous rotation drive mode, and the behavior of laundry exchanged in right and left positions by normal and reverse pivot rotation drive mode.
Moreover, injection port 51 is opened toward the direction of center of rotation of rotary drum 4 as shown in FIG. 9C, at the reverse side of front end wall 3h of water tank 3. More specifically, in passage 52 between front end wall 3h of water tank 3 and front end wall 4b of rotary drum 4, annular outlet 53 is opened and formed. Therefore, the circulation water injecting from injection port 51 is discharged efficiently to the rotation center side of rotary drum 4 in passage 52. Specifically, it is discharged efficiently into the inside rotation region in rotary drum 4 in the radial direction toward annular outlet 53. Therefore, regardless of the amount of the laundry, the circulation water can be supplied efficiently. Front end wall 3h of water tank 3 has inclined side 3h1 and curved side 3h2. Inclined side 3h1 is inclined to the rear side of washing machine main body 2 from the position corresponding to injection port 51 toward closer to the inner circumference. Curved side 3h2 is curved from inclined side 3h1 to the inner circumference, toward the side of opening of rotary drum 4. By front side wall 3h having inclined side 3h1 and curve side 3h2, the circulation water injected into passage 52 is discharged from inclined side 3h1 along curved side 3h2 as indicated by solid line arrow in FIG. 9C. That is, the circulation water injected into passage 52 is discharged to the inner side of rotary drum 4 through opening in rotary drum 4, so that the circulation water may be supplied to the laundry at high efficiency.
As shown in FIG. 9A to FIG. 9C, injection port 51 has connection opening 51a formed at front end wall 3h of water tank 3. Injection port 51 injects circulation water from connection port 51a connected to discharge side route 31b into passage 52. Injection port 51 is opened in a specified range in peripheral direction toward the rotation center side of rotary drum 4 toward passage 52. Thus, to provide connection port 51a in front end wall 3h of water tank 3, injection port 51 formed by opening toward passage 52. Thus, the circulation water from discharge side route 31b is smoothly guided to the side of passage 52 through injection port 51 without causing disturbance, and is stably discharged along with lateral spreading in specified direction from specified region corresponding to peripheral region of injection port 51 of annular outlet 53 in rotary drum 4. Therefore, the circulation water can be effectively supplied regardless of the amount of the laundry in rotary drum 4.
Injection port 51 is designed to guide the circulation water into the opening of passage 52 at connection end part 55d of discharge side route 31b connected to connection port 51a. Therefore, a mutual and simple shape cooperating with connection end part 55d may be combined with injection port 51 provided at connection port 51a connected to discharge side route 31b for guiding the circulation water to the side of passage 52. By such simple configuration, circulation water can be supplied favorably, regardless of the amount of laundry, such as broad discharge flow width in peripheral direction, discharge flow thickness sufficient in longitudinal direction, or discharge flow speed capable of increasing the water arrival distance. Moreover, the piping structure is not particularly complicated, and water leak risk is not raised, and the cost is not increased.
Injection port 51 opened nearly in the central position of bottom of front end wall 3h of water tank 3 as shown in FIG. 9A to FIG. 9C. Injection port 51 and discharge side route 31b are connected by means of resin duct 55 shown in FIG. 4, FIG. 9A to FIG. 9C. Duct 55 is formed in a flat shape back and forth by adhering two front and rear members 55a, 55b. Discharge side route 31b is disposed as being deviated to either right or left direction from the opening position of injection port 51, and is extended forward nearly parallel to the axial line of water tank 3 from circulation pump 20. Duct 55 connects between the front end of pipe-shaped discharge side route 31b and injection port 51. That is, connection pipe 55c formed integrally at one end of rear member 55b connected to discharge side route 31b as its extension. Front member 55a is extended almost horizontally nearly to the lower part of injection port 51 from one end of rear member 55b, and is curved to injection port 51, and connection end part 55d is formed. In connection end part 55d, as shown in FIG. 9C, connection port 55e formed integrally in rear member 55a is formed. Connection port 55e is connected to connection port 51a opened at front end wall 3h of water tank 3 through seal member 56, and fixed with screw 57. Thus, duct 55 connected from connection end part 55d with connection port 51a of front end wall 3h of water tank 3 to circulation pump 20 side extending to the outer circumference of water tank 3 is flat back and forth. Hence, piping can be installed in a small space between front end wall 3h of water tank 3 and the front wall of washing machine main body 2. Moreover, by the flat shape of duct 55, the circulation water can be straightened to stream width or stream thickness suited to the opening of injection port 51. As a result, the circulation water can be injected from the connection port 51a toward injection port 51 to be injected into passage 52, and thereby the large peripheral direction discharge width from annular outlet 53, discharge thickness sufficient in longitudinal direction, and discharge speed region capable of increasing the water arrival distance can be satisfied without disturbing the flow. As a result, the washing and rinsing effect may be further enhanced. Further, duct 55 is extended from the outer circumference of water tank 3 downward nearly to connection port 51a of injection port 51 in the lower part of front end wall 3h, and is connected to connection port 51a in the rising part curved to the connection part therefrom. Accordingly, the circulation water straightened into flat flow is guided into connection port 51a and injection port 51 matched in flattening direction without disturbing at the curved shape of the rising part, and is injected into specified region in peripheral direction of passage 52. Hence, the water is discharged stably from annular outlet 53 in a wide range, and the action of circulation water on the laundry is enhanced.
In particular, injection port 51 is formed so as to open toward annular outlet 53 between the upper edge of connection port 51a and arresting wall 5c formed integrally along front end wall 4b side of rotary drum 4 at right angle from connection port 51a opened at front end wall 3h of water tank 3. Between connection end part 55d and arresting wall 5e, throttling wall 55f is provided for throttling the injection passage smoothly from duct 55 side toward injection port 51 by a smooth curvature. As a result, the circulation water from duct 55 to injection port 51 is encouraged, and a high speed flow is produced toward sloped side 3h1 and curved side 3h2 of front end wall 3h of water tank 3. Accordingly, the circulation water flows like a parabolic curve while spreading laterally by discharging securely in a specified route behind an upward oblique direction into rotary drum 4, and is supplied to the laundry from a wider range in the rotary drum 4 in a long flight passage. To achieve a high speed flow, the throttling passage may be formed anywhere between connection end part 55d and injection port 51 to connection port 51a of duct 55. That is, the circulation water flowing into injection port 51 provided in connection port 51a is guided into passage 52 side. At this time, by simple shape matching state of connection port 51 of discharge side route 31b with connection end part 55, the working condition may be satisfied regardless of the amount of laundry, such as large discharge flow width in peripheral direction, discharge flow thickness sufficient in longitudinal direction, or discharge flow speed for increasing the water arrival distance. Moreover, the piping structure is not particularly complicated, and water leak risk is not raised, and the cost is not increased.
On front end wall 4b of rotary drum 4, as shown in FIG. 9C, annular rib convex part 4c is formed to cross passage 52 in peripheral direction. Throttling gap S is left between rib convex part 4c and slope 3h1. The position of rib convex part 4c is changed in the radial direction like corrugation. Accordingly, when rotary drum 4 rotates, rib convex part 4c dislocates its crossing position across passage 52 near injection port 51, that is, the forming position of throttling gap S in the radial direction as indicated by three specific positions (indicated by solid line and broken line) in FIG. 9C. As a result, the circulation water flow passing passage 52 toward annular outlet 53 is either throttled by throttling gap S near annular outlet 53, or throttled by throttling gap S at a position remote from annular outlet 53. Hence, the angle of the circulation water toward rotary drum 4 is deflected up and down, and the circulation water is deflected in a wide range in the axial direction of rotary drum 4, and applied to the laundry.
Rib convex part 4c is a discharge guide disposed unevenly in the peripheral direction at the side of front end wall 3h of rotary drum 4. Therefore, the discharge direction of circulation water injected into passage 52 and discharged from annular outlet 53 into rotary drum 4 is disturbed back and forth or is changed. Accordingly, the arrival position of discharged circulation water on the laundry in rotary drum 4 is disturbed back and forth or is changed. Such discharge guide acts to disturb back and forth or change the discharge direction in at least one of inner circumference corrugating in peripheral direction, wall surface corrugating back and forth in peripheral direction, rib convex part corrugating or intermittent in peripheral direction by protruding to the passage side, or blade, and obstacle changing the passing resistance of circulation water injected through passage, and these changes are combined as far as possible.
By such parabolic action and longitudinal distribution action, the circulation water is uniformly applied on the laundry also in the longitudinal direction, and the detergent dissolving effect, washing effect, and rinsing effect are reinforced.
Immediately above discharge port 36, baffle plate 61 is provided as shown in FIG. 3, FIG. 4, in order to prevent suction of laundry.
As explained herein, the present invention provides a drum type washing machine having a rotary drum formed in a cylindrical shape installed in a water tank so that the rotary shaft direction may be horizontal or inclined downward from the horizontal direction from the opened front side to the back side at the bottom, and capable of executing at least one of washing process and rinsing process by driving the rotary drum by a motor, and comprising a water circulation mechanism for circulating the water in the water tank by a circulation pump through a circulation route connected to the water tank, in which the water circulation mechanism has a passage for discharging the circulation water in the rotary drum provided between the front end wall reverse side of the water tank and the front end wall surface of the rotary drum.
In this configuration, only by connecting the circulation route to the front end wall of the water tank, the circulation route is linked to the passage formed between the front end walls of the water tank and rotary drum. Accordingly, every time the water circulation mechanism circulates by sucking the water in the water tank and returning to the water tank in the washing process and/or rinsing process by its circulation pump and circulation route, the circulation water is discharged into the rotary drum from an annular outlet formed in the inner circumferences of the both front end walls through this route without requiring any particular piping. The circulation water is discharged from the annular outlet between the inner circumferences of the front end walls through the passage between the front end walls of the water tank and rotary drum. Therefore, the laundry in the rotary drum is not interfered by any hooking or special shape or discharge port or other structure.
According to the present invention, the water circulation system has a connection port connected to the discharge side route from the circulation pump, and an injection port for injecting the circulation water from the connection port to the passage. This discharge port is opened in the passage in a specified range in peripheral direction toward the center of rotation of the rotary drum.
In this configuration, by forming the injection port opened toward the passage, the circulation water from the discharge side route can be smoothly guided to the passage side through the injection port without disturbance. Therefore, the water can be discharged stably in a proper lateral spread in specified direction from specified region corresponding to the peripheral region of the injection port of the annular outlet in the rotary drum.
Further according to the present invention, the injection port guides the circulation water into the opening to the passage between the discharge side route connected to the connection port and the connection end. In such configuration, moreover, the injection port provided at the connection port connected to the discharge side route guides the circulation water to the passage side, which is realized in a simple structure combined with the connection end to the connection port of the discharge side route.
Further according to the present invention, the discharge side route has a duct connected to the circulation pump side along the outer circumference of the water tank from the connection end, and this duct is flat in the longitudinal direction, and forms a throttling passage for throttling and injecting the circulation water toward the opening position to the passage of the injection port together with the discharge port.
In this configuration, since the duct is flat in the longitudinal direction, the required piping space for the duct is saved in the discharge side route between the front end wall of the water tank and the front wall of the washing machine main body. Moreover, the circulation water toward the connection port and injection port can be straightened in a flat and broad flow parallel to the spreading direction of the passage between the front end walls. Afterwards, from the connection port and the injection port to the passage, the circulation water is guided so that the flattening direction may be matched in the spreading direction in the peripheral direction, and is discharged into the rotary drum from the annular outlet matched in the flattening direction.
Further according to the present invention, the connection port of the injection port is positioned in a lower part of the front end wall of the water tank, and the duct is extended in lateral direction from the outer circumferential position of the water tank nearly to the lower part of the connection port of the injection port, and then curved upward to the connection port of the injection port, and is connected to the connection port of the injection port through the upward curved portion.
In this configuration, the circulation water is straightened into a flat flow, and is guided stably in lateral direction, and is further guided into the connection port smoothly without being disturbed along the curved shape of the upward curved portion. In this broad and flat flow, the water is stably discharged from a broader annular outlet along the injection port matched in the flattening direction and the passage between the front end walls.
Further according to the present invention, the passage allows the injected circulation water to be discharged obliquely backward and upward into the rotary drum from the annular outlet formed between the water tank and the front end wall of the rotary drum.
In this configuration, the discharged circulation water from the annular outlet is spread more broadly in the lateral direction along a long route of a parabolic curved directed obliquely backward and upward into the rotary drum.
Further according to the present invention, the reverse side of the front end wall of the water tank has a curved surface curved in the rotary drum inside direction at the inner circumferential side.
In this configuration, the circulation water injected from the injection port into the passage is guided toward a specified discharge direction into the rotary drum by the curved surface on the at the inner circumferential side of the reverse side of the front end wall of the water tank.
Further according to the present invention, the reverse side of the front end wall of the water tank has a slope inclined in the rotary drum direction from the connection port side of the injection port toward the curved surface.
In this configuration, the circulation water injected from the injection port to the passage is guided, on the reverse side of the front end wall of the water tank, up to the curved surface by inclining the flow along the slope inclined in the rotary drum direction from the connection port side of the injection port toward the curved surface, and is smoothly discharged into the rotary drum in the direction along the curved surface.
Further according to the present invention, the inner peripheral end of the front end wall of the water tank is protruding to the side of center of rotation from the inner peripheral end of the rotary drum.
In this configuration, by a slight protruding amount, the circulation water discharged from the annular outlet flows securely into the rotary drum in specified direction, and is prevented from splashing out of the water tank or rotary drum.
Further according to the present invention, the front end wall of the rotary drum has a discharge guide part not uniform in the peripheral direction, for disturbing in longitudinal direction or changing the discharge direction of circulation direction into the rotary drum through the passage along with rotation.
In this configuration, the discharge guide disturbs in longitudinal direction or changes the discharge direction of circulation water discharged into the rotary drum from the annular outlet injected into the passage. Therefore, the arrival position of the discharged circulation water on the laundry in the rotary drum is disturbed longitudinally or changed.
Further according to the present invention, the discharge guide is formed, on the front end wall of the rotary drum, at least one of inner circumference corrugating in peripheral direction, wall surface corrugating back and forth in peripheral direction, rib convex part or blade corrugating and/or intermittent in peripheral direction by protruding to the passage side, and obstacle changing the passing resistance of circulation water injected through the passage.
In this configuration, the discharge direction of the circulation water can be disturbed in the longitudinal direction or changed while the circulation water is discharged.

Claims

A drum type washing machine having a rotary drum (4) formed in a cylindrical shape installed in a water tank (3) so that the rotary shaft direction is horizontal or inclined downward from the horizontal direction from the opened front side to the back side at the drum bottom (3b), and capable of executing at least one of washing process and rinsing process by driving the rotary drum (4) by a motor (6),
wherein the water tank (3) comprises a front end wall (3h) around an opening (13), wherein the rotary drum (4) comprises a front end wall (4b) opposing the front end wall (3h) of the water tank (3),
wherein the washing machine comprises:
a water circulation system (16) configured to circulate the water in the water tank (3) by a circulation pump (20) through a circulation route (31) connected to the water tank (3), and
wherein the water circulation system (16) has a passage (52) for discharging the circulation water into the rotary drum (4),

characterized in that:
said passage (52) is formed between the front end wall (3h) of the water tank (3) and the front end wall (4b) of the rotary drum (4), and

said the passage (52) forms an annular outlet (53), said outlet (53) is composed of an end of the front end wall (3h) of the water tank (3) and an end of the front end wall (4b) of the rotary drum (4),

wherein the circulation water is discharged obliquely backward and upward into the rotary drum (4) from said annular outlet (53).
The drum type washing machine of claim 1, wherein the water circulation mechanism (16) has a connection port (51a) connected to the discharge side route (31b) from the circulation pump (20) and an injection port (51) configured to inject the circulation water from the connection port (51a) to said passage (52), and the injection port (51) is opened in said passage (52) in a specified range in peripheral direction toward the center of rotation of the rotary drum (4).
The drum type washing machine of claim 2, wherein the injection port (51) is configured to guide the circulation water into the opening to the passage (52) between the discharge side route (31 b) connected to the connection port (51a) and the connection end (55d).
The drum type washing machine of claim 3, wherein the discharge side route (31b) has a duct (55) connected to the circulation pump side along the outer circumference of the water tank (3) from the connection end (55d), and the duct (55) is flat in its longitudinal direction,
and forms a throttling passage (S) for throttling and injecting the circulation water toward the opening position to the passage (52) of the injection port (51) together with the discharge port.
The drum type washing machine of claim 4, wherein the connection port (51a) of the injection port (51) is positioned in a lower part of the front end wall (3h) of the water tank (3), and the duct (55) is extended in lateral direction from the outer circumferential position of the water tank (3) nearly to the lower part of the connection port (51a) of the injection port (51), and then curved upward to the connection port (51a) of the injection port (51), and is connected to the connection port (51a) of the injection port (51) through an upward curved portion.
The drum type washing machine of claim 1, wherein the reverse side of the front end wall (3h) of the water tank (3) has a curved surface (3h2) curved in the rotary drum inside direction at its inner circumferential side.
The drum type washing machine of claim 6, wherein the reverse side of the front end wall (3h) of the water tank (3) has a slope (3h1) inclined in the rotary drum direction from the connection port (51) side of the injection port toward the curved surface (3h2).
The drum type washing machine of claim 1, wherein the inner peripheral end of the front end wall (3h) of the water tank (3) is protruding to the side of center of rotation from the inner peripheral end of the rotary drum (4).
The drum type washing machine of claim 1, wherein the front end wall (4b) of the rotary drum (4) has a discharge guide part which is not uniform in the peripheral direction, for disturbing in longitudinal direction or changing the discharge direction of circulation water into the rotary drum (4) through the passage (52) along with rotation.
The drum type washing machine of any one of claims 1 to 9, wherein the discharge guide is formed of at least one of an inner circumference configured to corrugate in peripheral direction of the rotary drum (4), a wall surface configured to corrugate back and forth in peripheral direction, a rib convex part (4c) or blade configured to corrugate in peripheral direction by protruding to the passage side, a rib convex part or blade which is intermittent in peripheral direction by protruding to the passage side, and an obstacle configured to change the passing resistance of circulation water injected through the passage (52).