GB2566475A

GB2566475A - Washing machine water circulation system

Info

Publication number: GB2566475A
Application number: GB1714787.7A
Authority: GB
Inventors: Soheil Hamadeh Samer
Original assignee: Tochi Tech Ltd
Current assignee: Tochi Tech Ltd
Priority date: 2017-09-14
Filing date: 2017-09-14
Publication date: 2019-03-20
Also published as: GB201714787D0

Abstract

Disclosed is a water circulation system suitable for use in a washing machine comprising two cylindrical tubs 402,404 arranged concentrically and actuated by a driving unit. The system comprises an intermediate water storage tank 430, at least one sensor, and a processor. The processor is configured to add water to the intermediate water storage tank prior to operation of the driving unit. The intermediate water storage tank may be a hollow counterweight, or a hollow housing of the washing machine. The intermediate water storage may comprise at least one filling portion 442, a main body 448, a connecting conduit 446, and a transition portion 444. The at least one sensor may be disposed in the concentric tubs of the washing machine, or the intermediate water storage tank. Also disclosed is a method of circulating water in a washing machine, comprising the steps of detecting an operating mode of the washing machine, sensing a machine parameter, detecting characteristics of water inside an intermediate water storage tank, transferring water to or from the intermediate water storage tank, and feeding fresh water into the washing machine.

Description

WASHING MACHINE WATER CIRCULATION SYSTEM TECHNICAL FIELD OF INVENTION [0001] The invention relates to washing machines, particularly, the circulation of water in washing machines.

BACKGROUND [0002] A typical washing machine contains at least one cylindrical tub (i.e., the outer tub and inner drum), counterweights, an electric motor, a detergent tray, a drainage pump and a control assembly. A front-load washing machine consists of a washing tub rotating in the horizontal or nearly horizontal direction. Front-load washing machines consume less water than top-load configurations, but there is scope for refinement to reduce the consumption of fresh water and increase machine efficiency. Improper re-utilisation of wastewater adds to daily sewage, which increases the pollution of waterways. Also, additional sewage transport infrastructure is required and the size of the disposal area increases, if wastewater is not re-utilised. It also leads to increased monthly fresh water consumption and related economic burdens.

[0003] Multiple approaches have been proposed to recycle or reuse washingmachine wastewater are available in prior art. The most common approach would be connecting the drainage pipe to the toilet flush tank or to the wash basin. Very few approaches have been proposed to store wastewater in washing machines and reuse it for the next washing process or other domestic purposes. One such apparatus is described in art US Patent 6401499B1 and assigned to Clark et. al. describes an improved laundry washing machine equipped with multiple fluid tanks around the washing tub. All the fluid tanks are connected to the washing tub by the pipe and pump assembly to supply liquid storage. However, there is no provision for wastewater storage or recirculation to wash clothes.

[0004] Prior art reference US8490439B2 discloses a recirculation system, comprising a single outlet, located on the upper side of the tub bellows for inputting fresh water and removing re-circulated water from the bottom (sump) of the tub. Such a recirculation system takes wash water from the bottom of the tub and pumps it to an upper part of the rotatable drum to help wet the clothes and improve the wash-andrinse action. US5307650, US5606878, and US5829459 also disclose a water reservoir in washing machine which facilitates water circulation of prior rinse cycle water into next prewash. However, used water in the systems does not impart counterweight action during high-speed extraction and may require additional assembly space.

SUMMARY [0005] The recirculation system used in prior art front-load washing machine provide limited water storage capacity to facilitate water recirculation of prior rinse cycle water into next prewash. Further, it poses additional problems such as increase in carbon footprint due to non-recyclable nature of components such as counterweight.

[0006] The present invention provides a system for circulating the water in a washing machine according to claim 1. The system includes an intermediate water storage (IWS) and a water circulation system to reduce fresh water (FW) requirement in the washing machine. The washing machine comprises an IWS operatively connected to outer tub, water circulation system and driving units. The water circulation system may include at least one water circulation controller, drum rotation controller and/or auxiliary controller. The water circulation controller is essentially designed to control and manage water flow between the outer tub, outlet, IWS or a fresh water source (FWS) based on water characteristics, machine parameters and operating modes of the washing machine. The water circulation system circulates the water, for the first time from at least one source of water such as fresh water tap to the IWS. The present invention also provides a method of circulating the water in washing machine according to claim 10.

[0007] In an alternative embodiment, the IWS can act as a counterweight and obtains a fully deployed state at installation sites or during wash cycle. Therefore, it IWS in this embodiment not only recirculate water but also reduces transportation cost during installation of washing machine.

BRIEF DESCRIPTION OF THE DRAWINGS [0008] Various aspects of the invention and its embodiments are better understood by referring to the detailed description. To understand the invention, the detailed description should be read in conjunction with the drawings, in which:

[0009] FIG. 1 illustrates an exploded view of a prior art front-load washing machine in general;

[0010] FIG. 2A illustrates the water recirculation system according to the present invention;

[0011] FIG. 2B illustrates the water recirculation system processor sub-units providing adequate counterweight and water recirculation according to the present invention;

[0012] FIG. 3 is a flow diagram illustrating the method to provide counterweight and water recirculation according to the present invention;

[0013] FIG. 4 illustrates a cross section of exemplary front-load washing machine with an IWS, designed according to the present invention;

[0014] FIG. 5 illustrates an alternative embodiment of an IWS according to the present invention; and [0015] FIG. 6 illustrates an IWS as counterweight according to the present invention.

DESCRIPTION [0016] In FIG. 1, a prior art front-load washing machine 100, essentially comprises an outer tub 102 and inner drum 104, counterweights 106, a detergent tray and softener tray 108, an electric motor 110, a drainage pump 112 and/or a display 111. The outer tub 102 and inner drum 104 are disposed into a four vertical wall assembly, which forms the supporting housing 116. The front wall 118 is provided with an opening door 120 for the feeding cloth load. A drive shaft 122 is positioned in such a way that it rotates in a horizontal or nearly horizontal axis. The outer tub 102 is mounted onto the drive shaft 122. The drive shaft 122 is further connected to a variable-speed electric motor 110, which imparts a rotational motion to the inner drum 104.

[0017] The water recirculation system 200 containing washing machine processor 214, as illustrated in FIG. 2A and 2B, comprises at least one water circulation controller 224, one drum rotation controller 226, and one auxiliary controller 228. The system as disclosed in FIG. 2A, is essentially designed to control and manage water flow between the outer tub 202, inner drum 204, outlet 252, IWS 230, or a reservoir of fresh water 250 based on water characteristics, machine parameters and operating modes of washing machine. The water circulation controller 224 collects data from a first set of sensors 232 to determine the level and characteristics of water in fresh water source (FWS) 250, IWS 230, or any additional storage such as toilet tank attached thereto. The source of fresh water can be the reservoir 250 or flowing water such as tap water at home. Drum rotation controller 226 and auxiliary controller 228 provide the operating modes of the washing machine, respective water requirements (including water characteristics such as no contaminants in water for rinsing purpose), or any other input essential for determining the water requirements. In one embodiment, the water circulation controller, drum rotation controller and auxiliary controller can be integrated components of a single processor.

[0018] The water circulation controller 224 determines the extent of grey water stored in the IWS 230 that can be used, or the outlet water that can be stored in the intermediate storage 230 based on the select operating mode of the machine, water characteristics or machine parameters. The intermediate storage (IWS) 230 can have at least one compartment to store the water. Furthermore, water can be stored based on the quality in different compartments of the intermediate storage 230. In an exemplary scenario, the outlet water of spin cycle can be utilised in the wash cycle and the wash cycle outflow can be used in the next pre-wash cycle.

[0019] The water circulation controller 224 makes decisions based on the water characteristics and water requirements. In an exemplary scenario, wastewater from the rinse cycle could be stored for a particular period and used for the next wash/pre-wash cycle. To minimise water fouling, the water could be diverted to alternative applications such as drain or irrigation if water stored in the hollow IWS 230 is not used within a period of time.

[0020] The drum rotation controller 226 controls the rotation of the inner drum 204 based on the operating mode of the washing machine and inputs from a second set of sensors 234 or other controllers. The auxiliary controller 228 manages and controls the sealing of washing machine door 220, controls water heater 256, ensures timer accuracy during washing machine operations, or any other connected feature 254 of the same genus based on input signals from the third set of sensors and other controllers.

[0021] The first set of sensors (Sf) 232 as disclosed in FIG. 2A is disposed in the outer tub 202, inner drum 204, IWS 230, outlet 252, reservoir of fresh water 250 or any fluidic path of the washing machine for sensing water characteristics and machine parameters. The water characteristics include, but are not limited to, the measurement of chemical or physical properties such as pH level, turbidity, water density or water weight. Machine parameters include the measurement of the water level in the outer tub 202, inner drum 204 or IWS 230. The first set of sensors (Sp)

232 is optionally selected from chemical, biological, mechanical, thermal, electrical, magnetic sensing elements, or a combination thereof, to measure the essential parameters of water reusability. In preferred embodiment of invention, the first set of sensors (Sf) 232 at least sense water quantity in IWS 230 as water characteristics, which ranges between zero litres to full capacity of the IWS 230.

[0022] The second set of sensors (Ss) 234 as disclosed in FIG. 2B, is disposed at various positions of the machine to sense at least one parameter such as tub position, tub rotation speed, level of weight imbalance, vibrations, motor power output or drive electrical parameters (such as voltage, current, phase, and frequency). These parameters are required to generate drive signal through electric motor 210 for tub rotation, depending on the operating modes of washing machine. In preferred embodiment of invention, the second set of sensors (Ss) 234 at least sense weight imbalance as operating mode of washing machine, which ranges between zero kilograms to the maximum weight rating of the washing machine in addition to a safety factor. For instance if the weight rating is 5kg and safety factor is 30% then the maximum imbalance expected would be 5 x 1.3 = 6.5kg in an exemplary embodiment.

[0023] The third set of sensors (St) 236 as disclosed in FIG. 2B, is deployed at various positions of the washing machine to sense at least one auxiliary parameter such as door position, water temperature or lid position required for appropriate functioning of the machine. In the preferred embodiment, multiple arrays of sensors are disposed to measure water parameters, machine parameters and operating modes of the washing machine. The sensors can be positioned in the outer tub 202, inner drum 204, IWS 230, outlet 252, and reservoir of fresh water 250 or any fluidic path of the washing machine. In preferred embodiment of invention, the third set of sensors (St) 236 at least sense temperature of water in the outer tub 202, inner drum 204, IWS 230, outlet 252, reservoir of fresh water 250 or any fluidic path of the washing machine as auxiliary parameter, which ranges between minimum temperature (Mini in degrees Celsius) at reservoir of fresh water 250 and maximum allowable temperature (Maxj in degrees Celsius) due to water heater 256 in washing machine cycle.

[0024] The water circulation controller 224 is connected to at least one valve, which is disposed in the fluid flow path to regulate the water flow. A first valve 238 is disposed in the IWS 230 described according to the embodiments of the present invention. The IWS 230 as disclosed in 2A comprises sub-components, such as an inlet 242, transition portion 244, connecting conduits 246, main body 248 and drainage outlet 249. The inlet portion 242 is positioned in such a way that it facilitates the flow of water into the main body 248. The position of the inlet 242 can be on top, bottom or sideways and receives the water from a reservoir 250 or any other connected water sources. The transition portion 244 is positioned in such a way that it facilitates the unidirectional flow towards the main body 248, and enables a flow control devices such as valves to allow water flow. Preferably, the first valve 238 is disposed in the transition portion 244 of the IWS 230 and facilitates unidirectional flow. The first valve 238 is actuated to receive water from the reservoir 250, connected through a fluid path, when water in the IWS 230 is not sufficient or below a threshold value required for machine operation. The first valve 238 in the transition portion 244 is closed once the required amount of water is allowed to pass through the first valve 238. Alternatively, the first valve 238 can be actuated to introduce fresh water into the outer tub 202.

[0025] A second valve 240 is disposed in the conducting conduits 246 of the

IWS 230. This second valve 240 is actuated to allow fluid flow between the IWS 230 and outer tub 202. The first and second valves receive an input signal 258 from the water circulation controller 224 based on machine parameter, water characteristics and mode of operation. Valves to regulate water can be selected from any of the available mechanism such as pneumatic, pressure, hydraulic, electric and electromechanical. In alternative embodiment, the water circulation controller 224 will load fresh water either automatically or on manual input when washing machine was used by the user to wash heavily soiled clothes or clothes containing active biological substances such as nappies. Water circulation controller 224 will eventually divert the greywater towards outside from outer tub 202 if greywater is unsuitable to store in IWS 230. In this case greywater will be directly discharged through the outlet 252 connected to the outer tub 202 with or without active pump 280 [0026] An Error Check and Feedback module 260 in the washing machine processor 214 is operatively connected to various controllers through a communication bus (as shown in FIG. 2B) to regulate the coordinated signal transfer, detect malfunction and sequence interlock in case of failure through embedded programs. The processor 214 is provided with a memory module 262 where all programs essential for machine operations and wash cycle-related data are stored.

[0027] In another embodiment of this invention, the processor 214 includes a Communication Module 264 to input the operating signal 266 such as operating mode, select signal and output the signals to various indicators about the real-time status of wash the cycle, which includes at least wash timer and alarms. In an alternative embodiment, the Communication Module 264 may include the functionality to communicate with an external network. The communicated data is optionally selected from amount of water reused, fresh water consumption, electricity intake, wastewater substance concentrations. Communication module 264 is advantageously connected to share performance data in order to establish connected machine environment. Furthermore, the processor 214 includes components such as display control 268 and data log module 270 to receive the user input and manage the received data from a set of sensors as disclosed in the invention.

[0028] In an alternative embodiment of the invention, the system is modified to provide adequate counterweight during each washing cycle on manual inputs from user.

[0029] FIG. 3 discloses an exemplary method to circulate water 300 in accordance with the present invention. A few modifications can be introduced based on the washing machine’s operating modes and type of clothes.

[0030] As a person with ordinary skills in the art may recognise substantially equivalent structures or acts to achieve the same results in the same (or a dissimilar) manner, the exemplary embodiment should not be interpreted as limiting the invention to one embodiment. The washing machine’s operation according to present invention comprises steps of installing washing machine at user site, which includes placing machine on floor and IWS is operatively connected with outer tub and inner drum. Subsequently before switching on the washing machine, user assembles hose joint connections for water inlet and outlet and plug is inserted into suitable main power supply. Laundry or clothes are segregated and selected pieces are loaded into the washing machine 302 and detergent, softeners and bleaches are added as required into the washing machine. Once the user starts the machine 304, the machine preferably makes a series of checks such as if the door is open or if water level is insufficient and displays the result in case of any error 308. Various modifications in loading of washing machine such as program dial, control panel functions, alarms, working current levels, and water pressure are possible according to scope of invention without departing from the spirit of the invention. The user then sets washing machine instruction 306 by making adjustments or selections from a range of controls. Setting washing instructions 306 may refer to one or more of any or all of the following: pre-wash, wash, rinse where each could end with a sub-cycle of drain and/or spin or none. Setting washing instructions 306 may also refer to things such as hot wash, cold wash, material, dirt, biologically contaminated, color, fabric weight, etc. Once the user completes setting washing instructions 306 the machine preferably makes a series of checks such as comparing the load with the cloth load capacity threshold. An error signal is generated 308 in case the cloth load is more than the capacity threshold or in case of any other error that stops the washing machine from operating according to the set washing instructions.

[0031] The system then determines which washing cycle types (Cx) is to be executed based on the set washing instructions 306. The washing cycle type (Cx) is numbered 5 as Ci, C2, C3, C4.... Cn and refer to pre-wash, quick wash, hard wash, rinse and spin or other cycle type corresponding to operation. The system as disclosed in the invention also determines all washing cycle parameters (Pw)· Washing cycle parameters (Pw) may include present quantity in IWS (IWS_Qpresent), threshold required quantity in IWS (IWS_Qthreshoid)· The washing cycle parameters (Pw) are 10 numbered as Ρχ, P2, P3, P4, P5, Ρβ, P7...PN and refers to present quantity in IWS (IWS_Q_preSent), threshold quantity required IWS_Qthreshoid to execute specific wash cycle (Cx), maximum possible quantity in IWS (IWS_Q_maxi_mum), IWS water detergent concentration (IWS_Detergent_COnc.), IWS water hardness (IWS_water_hardness), IWS water biological demand (IWS_water_biodemandh and IWS water microbial concentration 15 (IWS_water_microbe) and other water parameters corresponding to operation. The determined washing cycles types (Cx) and washing cycle parameters (Pw) information is then included in a parameter calculation matrix (Me) as shown in Table 1.

TABLE 1

	Washing cycle type (Cx)
Washing cycle parameters (Pw)	Ci	c₂	c₃	c₄	c₅	C_N
Pi	Present quantity in IWS (IWS_Q_preSent)	C1P1	C₂Pi	C3P1	C4P1	C5P1	C_nPi
P2	Threshold required quantity in IWS (HVS_Qthreshold)	C1P2	C2P2	C3P2	C4P2	C₅P₂	C_nP₂
P3	Maximum possible quantity in	C1P3	C2P3	C3P3	C4P3	C₅P₃	c_np₃

	IWS (IWS_Q_maximum)
P4	IWS water detergent concentration (IWS_Detergent_COnc.)	C1P4	C2P4	C3P4	C4P4	C₅P₄	C_nP₄
p₅	IWS water hardness (IW S water_hardness)	CiP₅	C₂P₅	C₃p₅	C₄P₅	C₅P₅	c_np₅
Pe	IWS water biological demand (IW S water_biodemand)	CiP₆	C₂P₆	C3P6	C4P6	C₅P₆	C_nP₆
P7	IWS water microbial concentration (IWS_water_microbe)	C1P7	C2P7	C3P7	C4P7	C₅P₇	C_NP?
Pn	Other IWS water parameter (IWS_N)	CiP_N	C2PN	C3PN	C₄P_N	C5PN	CnPn

Each row of calculation matrix (Me) corresponds to physical, biological and chemical washing cycle parameters (Pw) of water in IWS. Parameters (Pw ) are obtained from first set of sensors (Sp). The water circulation controller, as disclosed in earlier figures, computes individual washing cycle parameters (Pw) value in each row before starting the washing cycle type (Cx) and updates the parameter calculation matrix (Me). User may select any washing cycle type (Cx) from Ci, C2, C3, C4, C5, Ce to CnThen, the the first set of sensor (Sf) checks fresh water source (FWS) status 312 and following parameters values (both actually sensed and required) to execute the selected washing cycle type (Cx) by the user.

IWS water quantity parameters (314 and 318)-

Present quantity in IWS (IWS_Q_present) ke. CnPi;

Threshold required quantity in IWS (IWS_Qthreshoid) i.e· CnP2;

Maximum possible quantity in IWS (IWS Qmaximnm) i.e. CnP3.

IWS water quality parameters (316 and 320) 10

IWS water detergent concentration (IWS_Detergent_conc.)i-e. CnP4;

IWS water hardness (IWS_water_hardness) i.e. C_NPs;

IWS water biological demand (IWS_water_biodemand) i.e. C_NPe;

IWS water microbial concentration (IWS_water_microbe) i-e. CnP7.

The individual washing cycle parameters (Pw) value is optionally calculated to decide the required water quantity and quality and expressed as below Ση ; Where K is a washing cycle type constant.

[0032] For example, If the user feeds instruction for any of the above mentioned washing cycle type, for instance, prewash cycle (Ci); the first set of sensor (Sf) checks fresh water source (FWS) status 312 and following parameters values (both actually sensed and required) to execute first pre-wash cycle (Ci) -

IWS water quantity parameters (314 and 318)- o Present quantity in IWS (IWS_Q_present) i-e. CiPi;

o Threshold required quantity in IWS (IWS_Qthreshoid) i-e. C1P2;

Maximum possible quantity in IWS (IWS_Q_maxi_mum) i.e. C1P3.

IWS water quality parameters (316 and 320) -

IWS water detergent concentration (IWS_Detergent_conc )i.e. C1P4;

IWS water hardness (IWS_water_hardness) i.e. CiP₅;

IWS water biological demand (IWS_water_biodemand) i-e. CiP₆;

IWS water microbial concentration (IWS_water_microbe) i.e. C1P7.

Water circulation controller in subsequent step match calculated values with required values - for pre-wash cycle (Ci) and sends message to display accordingly; i.e. if parameters are not matched with required values it displays error 310 or else it starts pre-wash cycle with updated parameter calculation matrix (Me) 324. In later case, water circulation controller loads water into the outer tub and inner drum from the IWS 328 and FWS 330 as determined by the updated parameter calculation matrix (Me). In the preferred mode, the water parameters are checked by taking information from the first set of sensors (Sp) deployed in the IWS. Alternatively, the water can be used based on the pre-stored information regarding the water in the IWS. The prestored information includes, but is not limited to, the number of days since the water is stored, water source (such as previous wash cycle, fresh water and previous prewash cycle) and quantity of water. Once the first pre-wash cycle is executed 332, the used greywater can be loaded back to the IWS for use in next pre-wash cycle or alternatively directed to any other storage tank as per parameter calculation matrix (Me) 334. The water circulation controller according to present invention assesses the water quality & quantity parameters in IWS or any other storage tank before using in next pre-wash cycle 340, to determine if water is suitable to be used in next per-wash. The exemplary water parameters include physical, biological and chemical measurements, which are not limited to detergent concentration, circulating water quantity in the inner drum and hardness of water, biological substance concentration, biological oxygen demand etc. In the preferred embodiment, the water of storage tank is directed towards domestic applications such as toilet flush and gardens, to advantageously reduce the overall water consumption, if found not suitable either by longer accumulation or increased biological demand 336.

[0033] The auxiliary controller detects the sealing of the door and receives the inputs from the user interface whereas drum rotation controller receives input form third set of sensor (St) and second set of sensors (Ss) respectively and integrates the data with water circulation controller at step 308 before executing cycle.

[0034] In alternative embodiment, the water circulation controller will load fresh water either automatically or on manual input when washing machine was used by the user to wash heavily soiled clothes or clothes containing active biological substances such as nappies. In this case greywater becomes unsuitable to store in IWS and will be directly discharged to the drains 336.

[0035] When the operating mode is quick wash cycle (C2), the water circulation controller executes similar steps as discussed earlier, i.e. Error check, FWS status check, IWS water quantity and quality parameters (Pw) value calculation, parameter calculation matrix (Me) updation, filling required water quantity, cycle execution, and storage/disposal of used water based on parameter matrix. Thus, the water from the IWS is introduced into any subsequent wash cycle (Cx), if it meets the desired quality with or without dilution using fresh water. If water quantity in IWS is not adequate, then an error message would be displayed 310 and the water circulation controller will load fresh water (FW) into the machine as per updated parameter matrix (Me). The fresh water (FW) from the FWS is mixed with greywater 330 only if the quantity of greywater is less or the threshold of water characteristics can be met by adding fresh water; else, water from the intermediate storage is used 328. Once the wash cycle is complete at first instance by using water as described in step 332, the water can be optionally stored in one of the compartments of IWS 334 as disclosed in the invention, for use in next pre-wash/wash cycle or alternatively directed to any other storage tank 334. The water circulation controller according to present invention alternatively assesses at least physical, biological and chemical water parameters for individual compartments of IWS or any other storage tank before executing next wash cycle 340, to determine if water is suitable to be used in next wash cycle type by updating parameter matrix (Me).

[0036] When the operating mode is rinse and spin cycle (C4), the water circulation controller executes similar steps as discussed earlier i.e. Error check, FWS status check, IWS water quantity and quality parameters (Pw) value calculation, and parameter calculation matrix (Me) updation; the fresh water is directly loaded to outer tub and inner drum. Once the first rinse cycle is complete 332 by using fresh water, the used water can be stored in IWS 334 as disclosed in the invention, for use in next pre-wash/wash cycle or alternatively directed to any other storage tank 334 as per updated parameter matrix (Me). The water circulation controller according to present invention assesses at least physical, biological and chemical water parameters for IWS or any other storage tank water before using in next pre-wash cycle 340. Washing method according to present invention also includes the spin cycle after rinse cycle, to ensure removal of all the detergent, bleach and other cleaning agents at higher speed. It rotates the inner drum to extract remaining water from clothes by applying centrifugal force around rotational axis. In the preferred embodiment, the greywater from the rinse cycle is used in the wash/pre-wash cycle, while that from the wash cycle is used in the next pre-wash cycle. However, different fluidic connections can be opted based on the water characteristics, operating mode of the washing machine and availability of the fresh water.

[0036] An exemplary structural design of the water circulation system 400 has been represented in Fig. 4, wherein the cross section of the washing machine has been exhibited. The outer tub 402 and inner drum 404 of the washing machine are aligned around the axis of rotation 403 in such a way to enable free movement of the inner drum 404. The outer tub 402 is attached to the housing of the washing machine using a support spring 405. Alternatively, it can be attached to the IWS 430 or any other fixed component of the washing machine. The IWS 430 has been positioned around the arrangement of the outer tub 402 and inner drum 404 in such a way that fluidic connection can be created between the outer tub 402 and IWS 430. Alternatively, any other design structure such as external IWS placed at a distant place connected via a fluidic conduit can be opted depending on the design of the washing machine and availability of internal space. The water flows from IWS 430 to outer tub 402 through connecting conduit 446. A second valve 440 is placed to control the flow of the water through the connecting conduit 446. In addition, a pump (not shown) can be utilised for the appropriate flow of the water between the outer tub 402 and IWS 430. A conduit is connected with IWS 430 and transfer the water from various sources (such as fresh water from tap or greywater from tub). A first valve 438 is used to regulate the flow of the water. An outlet 452 of outer tub 402 is equipped with the first set of sensor (Sf) to detect the quality of water. These sensors send inputs to the water circulation controller as discussed above, which further decides whether to recycle the water and store it in the intermediate storage 430 or direct it to the drainage outlet 449 or outlet 452 of outer tub 402. Furthermore, the data related to the operating mode of the machine is stored in the memory module during the recycling process. In preferred embodiment of invention, the first set of sensors (Sp) detects the quality of water and sends inputs to the water circulation controller. The controller additionally processes the data obtained for multiple parameters during previous wash cycle from second set of sensors (Ss) and third set of sensors (St) to calculate water quality and rate it on the scale of 1-10. The lower values indicates very clean water which can be used in subsequent cycles and higher values indicates dirty or contaminated water which is directed to the outlet 452 of outer tub 402.

[0037] In another aspect of this invention, the IWS 430, which acts as a storage means, can be replaced with a hollow counterweight, hollow housing of the washing machine, an external tank or any other fluidically connected liquid storage. In this scenario, the counterweight includes at least one inlet 442, a transition portion 444, a main body 448 and a connecting conduit 446. The counterweight is deployed in two steps: a first partially deployed state at a manufacturer’s factory and a first fully deployed state after the installation of a machine at the user site or during a wash process. Furthermore, the counterweight attains a second, undeployed/deactivated state during transfer, reinstallation or maintenance. The water recirculation system is enabled with the integration of three controllers to calculate the required counterweight quantity during each rotation cycle. The effective counterweight quantity is calculated considering the parameters of the water, machine, imbalance and operating modes of the washing machine.

[0038] In an alternative embodiment, as shown in Fig. 5, a cubical IWS 530 acts as a supporting housing of the washing machine or washing machine components are provided in an encastre design. The exemplary embodiment described in figure 5 , along with the modifications covered, may be recognised by person skilled in art as substantially equivalent structures or act to achieve the same results in the same (or a dissimilar) manner and should not be interpreted as limiting the invention to one embodiment. The counterweight includes at least one inlet 542, a transition portion 544, a main body 548 and a connecting conduit 546. In addition, the main body is provided with interconnecting profiles 571, interconnecting passage 513 and single outlet 573.

[0039] The structural design of the IWS as a counterweight has been shown in

Fig. 6. The IWS 630 comprises sub-components, such as an inlet 642, transition portion 644, connecting conduits 646, main body 648 and drainage outlet 649 positioned around a horizontal axis 603. The inlet portion 642 is positioned in such a way that it facilitates the flow of water into the main body 648. The position of the inlet 642 can be on top, bottom or sideways and receives the water from a reservoir or any other water sources. The transition portion 644 is positioned in a way that allows the unidirectional flow towards the main body, and enabled a flow control devices such as valves. The IWS 630 discussed above is deployed in two states at two different sites. The first partially deployed state is attained at the manufacturer’s factory site and the first fully deployed state is attained at the user site after the frontload washing machine has been installed and filled with water. The second undeployed/deactivated state is attained whenever the IWS is dissembled from the supporting housing during transfer, reinstallation or maintenance. Thus, the IWS 630 is advantageously deployed in two states to reduce the increased assembly weight, cost and additional effort needed when transporting the machine from the factory to the consumer site.

[0040] To attain the first fully deployed state, the IWS inlet portion 642 is connected to the fresh water reservoir. The filling is regulated using a water circulation controller, which measures the water level with three sets of sensors and subsequently initiates the wash cycle once the threshold level is reached. A typical washing process passes through four phases: prewash, washing and tumbling, rinsing, and spin. In the prewash phase, the load is added with detergent and torque is transferred to the inner drum. Subsequently in the washing and tumbling phase, the inner drum is rotated at low and high speeds using the variable speed electric motor. This washing sub-cycle is repeated for required time followed by the rinsing cycle, similar to the washing cycle (without the addition of the detergent). Finally, the washed clothes are subjected to a process of high-speed extraction, where the water is drained out and pumped through inner drum holes and stored in IWS or allowed to flow to the drains, according to the present invention.

[0041] In the preferred embodiments of the invention, the processor is modified to provide adequate counterweight during each phase of washing cycle. When the IWS acts as a counterweight, the controller is enabled through the integration of sensor data to calculate the required amount of counterweight during each rotation cycle. The effective counterweight quantity is calculated considering the parameters of the water, machine, imbalance and operating modes of the washing machine. The exemplary water parameters include physical, biological and chemical measurements, which are not limited to detergent concentration, circulating water quantity in the inner drum and hardness of water. Similarly, the machine parameters comprise at least cloth load, water capacity or combination thereof and the operating modes comprise at least automatic, manual or combination thereof.

[0042] As a person with ordinary skills in the art may recognise substantially equivalent structures or acts to achieve the same results in the same (or a dissimilar) manner, the exemplary embodiment should not be interpreted as limiting the invention to one embodiment. Various modifications in shape of counterweight (cylindrical, semi-cylindrical, cube, rectangular, pentagonal), number, inlet position (top, bottom, side, front and rear face of counterweight), connecting channels, sealing 5 means (lid, cover, plug, tap), disposal position (cylindrical devices, drive shaft or lower portion of the outer drum), valve structure (pneumatic, electro-mechanical) are possible according to scope of invention without departing from the spirit of the invention.

Claims

CLAIMS:

1. A system for circulating the water in a washing machine comprising:

at least one arrangement of two cylindrical tubs; wherein an inner tub is actuated through a driving unit and an outer tub is connected to a fixed component of the washing machine;

at least one inlet for connection to a source of fresh water;

at least one outlet of used water;

at least one intermediate water storage; and a processor to control and manage water flow between the cylindrical tubs, outlet, intermediate water storage, or source of fresh water based on the water characteristics, machine parameters and operating modes of washing machine using at least one sensor;

wherein the processor is configured to add water to intermediate water storage prior to operation of driving unit.

2. A system of claim 1, wherein the fixed component of the washing machine is intermediate storage, support housing, or wall.

3. A system of claim 1, wherein the intermediate water storage is a hollow counterweight, hollow housing of the washing machine, or any other fluidically connected liquid storage.

4. A system of claim 3, wherein the intermediate water storage comprises at least one filling portion, a main body, connecting conduit and transition portion.

5. A system of claim 1, wherein the sensors are disposed in the cylindrical tubs, intermediate water storage, outlet, source of fresh water, or any fluidic path of the washing machine.

6. A system of claim 1, wherein the water characteristics are chemical, biological or physical properties.

7. A system of claim 1, wherein the machine parameter comprises at least cloth load, water capacity, detergent concentration, water conditioner or combination thereof.

8. A system of claim 1, wherein the operating modes comprises at least automatic, manual, pre-wash, rinse or any other mode of operation.

9. A system of claim 1, wherein the outlet is connected to toilet tank, garden tank or any other external storage.

10. A method of circulating the water in washing machine comprising:

detecting the operating mode of the washing machine;

sensing the machine parameter in at least one arrangement of two cylindrical tubs, or at least one intermediate water storage;

detecting, using at least one sensor, the characteristics of water of the intermediate water storage and the tubs;

transferring the water from the intermediate storage to the tub, tub to intermediate storage, tub to outlet, intermediate storage to outlet, or any combination thereto based on the operating mode of washing machine, water characteristics, level of the water, or combination thereof; and feeding fresh water into the washing machine; wherein fresh water is fed on the unavailability of water of desired characteristics in the intermediate water storage or cylindrical tubs.

11. A method of claim 10, wherein the water characteristics are chemical, biological or physical properties.

12. A method of claim 10, wherein the machine parameter comprises at least cloth

5 load, water capacity, detergent concentration, water conditioner or combination thereof.

13. A method of claim 10, wherein the operating modes comprises at least automatic, manual, pre-wash, spin, rinse or any other mode of operation.

14. A method of claim 13, wherein the water of rinse or spin mode is used in prewash or wash mode of the machine or else discharged to the drains.