EP2723934A1

EP2723934A1 - Washing machine with filtration unit

Info

Publication number: EP2723934A1
Application number: EP12729137.5A
Authority: EP
Inventors: Ilkan Erdem; Zehra Ulger; Emre Ozturk; Serife Birgul Tantekin ERSOLMAZ; William Bill KRANTZ
Original assignee: Arcelik AS
Current assignee: Arcelik AS
Priority date: 2011-06-27
Filing date: 2012-06-22
Publication date: 2014-04-30
Anticipated expiration: 2032-06-22
Also published as: EP2723934B1; WO2013000839A1; TR201106342A1; PL2723934T3

Abstract

The present invention relates to a washing machine (1) comprising a tub (2), at least one water inlet valve (3, 103) that provides water intake into the tub (2) from the water mains (S), a cross-flow type filtration unit (4), passing water through a nanofilter (NF) thus providing the removal of the hardness of water, a soft water line (5) that provides the water removed of its hardness in the filtration unit (4) to be transferred to the tub (2), a detergent dispenser (6), a reservoir (9) connected to the first water inlet valve (3) and open to atmospheric pressure, a supply line (10) that provides circulation of the water between the reservoir (9) and the filtration unit (4) and transfers water to the filtration unit (4), a return conduit (11) that provides the transfer of the hard water flowing through the filtration unit (4) to the reservoir (9) and a circulation pump (12) disposed on the supply line (10), providing the water to be circulated between the reservoir (9) and the filtration unit (4) and the water in the reservoir (9) to be transferred to the filtration unit (4) under pressure.

Description

WASHING MACHINE WITH FILTRATION UNIT

The present invention relates to a washing machine comprising a filtration unit used for the water softening process.
In washing machines, Ca⁺⁺ and Mg⁺⁺ ions that increase the hardness of water are present in the water received from the water mains and used in the washing process. The ions that increase water hardness join with the surfactants present in the detergent and decrease the cleaning properties of these agents thus the desired cleanliness of the laundry cannot be achieved. The ions that increase water hardness furthermore cause lime accumulation on components like the heater by forming deposits in hot water.
In the state of the art, water softening devices are used for decreasing the hardness of the washing water and for providing an effective washing. The water softening device comprises an ion exchanger and a salt container that provides the regeneration process to be performed by keeping the resin in salty water at the ion exchanger in the regeneration process. The conventional water softening devices provide an unpractical solution for the user since they need addition of salt periodically. The salty and hard water having excessively corrosive effect is discharged to the outside due to the regeneration of the ion exchanger and rinsing thereof at the end of regeneration. This waste water formed in regeneration processes causes rusting in the metal components of the washing machine.
In the state of the art, utilization of cross-flow filtration systems is also known for decreasing the hardness of water. In the implementation of cross-flow filtration, water is passed tangentially over a membrane and water is separated into two as soft and hard water. In this type of filtration systems, water has to be transferred under pressure on the membrane and capacity of producing soft water is low.
In the United States Patent Application No. US20050252533, a washing system is described wherein a nanofiltration device is used for softening the water.
The aim of the present invention is the realization of a washing machine wherein water is softened by means of a cross-flow filtration unit and water saving is provided.
The washing machine realized in order to attain the aim of the present invention, explicated in the first claim and the respective claims thereof, comprises a reservoir connected to the water inlet valve and open to atmospheric pressure, a filtration unit that provides the water to be softened by being filtered and a soft water line that transfers the soft water filtered in the filtration unit to the tub and a rinsing water line that delivers the hard water collected in the reservoir into the tub for use in the rinsing steps and a water outlet valve that is provided on this line. The control unit opens the water outlet valve in the laundry rinsing steps executed after the main washing program with detergent and provides the hard water collected in the reservoir to be transferred to the tub.
In another embodiment of the present invention, the washing machine comprises the soft water line and the rinsing water line that transfer water to the tub from an inlet opening on the tub independently from the detergent dispenser. Water is received into the detergent dispenser and the reservoir from two separate water inlet valves, after the detergents are flushed by receiving a small amount of water into the detergent dispenser, the water inlet valve connected to the detergent dispenser is closed and water is filled into the reservoir by opening the water inlet valve connected to the reservoir. The water filled into the reservoir is transferred to the filtration unit for softening, here soft water and hard water are separated from each other and soft water and hard water are transferred to the tub without passing through the detergent dispenser. Soft water is transferred to the tub from the inlet opening in the washing steps and hard water in the rinsing steps.
In an embodiment of the present invention, one end of the soft water line is connected to the filtration unit, the other end to the detergent dispenser and soft water is transferred to the tub through the detergent dispenser.
In another embodiment of the present invention, a soft water valve is disposed on the soft water line and pressurized soft water is transferred to the detergent dispenser.
In another embodiment of the present invention, the rinsing water line is connected to the detergent dispenser together with the soft water line and hard water is transferred to the tub through the detergent dispenser. In this embodiment, the existing detergent dispenser connection is used for transferring hard water to the tub and utilization of a separate line is not deemed necessary.
In the washing machine of the present invention, the hard water separated from the filtration unit in the water softening process is not discharged outside and by using in the laundry rinsing processes water saving is provided.
The washing machine realized in order to attain the aim of the present invention is illustrated in the attached figures, where:
Figure 1 - is the schematic view of a washing machine.
Figure 2 - is the schematic view of the washing machine wherein the soft water line and the rinsing water line are connected to the tub.
Figure 3 - is the schematic view of the washing machine wherein the soft water line and the rinsing water line are connected to the detergent dispenser.
Figure 4 - is the schematic view of the washing machine wherein a pump is disposed on the soft water line.
The elements illustrated in the figures are numbered as follows:

Washing machine
Tub
, 103 Water inlet valve
Filtration unit
Soft water line
Detergent dispenser
Discharge pump
Control unit
Reservoir
Supply line
Return conduit
Circulation pump
Rinsing water line
Water outlet valve
Soft water pump
Inlet opening

The washing machine (1) comprises a tub (2) wherein the washing process is performed, at least one water inlet valve (3, 103) that provides water intake into the tub (2) from the water mains (S) to be used in the washing program, a cross-flow type filtration unit (4), functioning as “water softening device”, that separates ions like Ca⁺⁺, Mg⁺⁺ by passing water through a nanofilter (NF) thus providing the removal of the hardness of water, a soft water line (5) that provides transferring of the water removed of hardness by being filtered in the filtration unit (4) to the tub (2), a detergent dispenser (6) wherein the cleaning agents such detergents, etc. are placed, a discharge pump (7) providing water to be discharged at the end of the washing program and a control unit (8) that regulates the water softening processes and the washing programs.
The washing machine (1) furthermore comprises a reservoir (9) connected to the first water inlet valve (3) and open to atmospheric pressure, a supply line (10) that provides continuous circulation of water between the reservoir (9) and the filtration unit (4), transferring water to the filtration unit (4), a return conduit (11) that provides the transfer of the hard water running down from the nanofilter (NF) (not passing through) by flowing together with the substances trapped on the surface of the nanofilter (NF) in the filtration unit (4) to the reservoir (9) and a circulation pump (12) disposed on the supply line (10), providing the circulation of the water between the reservoir (9) and the filtration unit (4) and the transfer of the water in the reservoir (9) under pressure to the filtration unit (4).
The washing machine (1) of the present invention comprises
- a rinsing water line (13) that transfers hard water from the reservoir (9) to the tub (2),
- a water outlet valve (14) located on the rinsing water line (13) and
- the control unit (8) that opens the water outlet valve (14) in the laundry rinsing steps executed after the main washing programs with detergent, providing the hard water collected in the reservoir (9) to be transferred to the tub (2) (Figure 1).
The control unit (8) closes the water outlet valve (14) in the water softening process performed by circulating water between the filtration unit (4) and the reservoir (9) and in the main washing steps wherein detergent is used, thus preventing the hard water collected in the reservoir (9) from being transferred to the tub (2). In the steps of main washing with detergent, soft water is used which is produced in the filtration unit (4) and transferred to the tub (2) from the soft water line (5). The control unit (8) opens the water outlet valve (14) in the rinsing steps wherein detergent is not used and provides the hard water collected in the reservoir (9) to be transferred to the tub (2). The water received from the water mains (S) by means of the first water inlet valve (3) and collected in the reservoir (9), is passed through the filtration unit (4) by means of the supply line (10) and the circulation pump (12) and the water passing over the nanofilter (NF) in the filtration unit (4) is separated into two as hard water and soft water. The water removed of its hardness is transferred to the tub (2) by means of the soft water line (5) in order to be used in the main washing processes. The hard water leaving the filtration unit (4) is transferred to the reservoir (9) through the return conduit (11) and continues to be circulated between the filtration unit (4) and the reservoir (9) by means of the circulation pump (12). In the start of the water softening process, the ratio of hard water/soft water leaving the filtration unit (4) is approximately 5/1 – 6/1, the circulation of water between the reservoir (9) and the filtration unit (4) continues and at the end of the water softening process, the ratio of hard water/soft water becomes 1/1 approximately. If for example 2 units of water is received from the first water inlet valve (3), 1 unit of soft water leaving the filtration unit (4) is transferred to the tub (2) and 1 unit of hard water is collected in the reservoir (9). The hard water collected in the reservoir (9) is not discharged, but transferred to the tub (2) by opening the water outlet valve (14) in the rinsing steps and the laundry is rinsed. In the rinsing steps, the interaction of hard water with detergent is not possible since detergent is not used and a negative situation is not observed in the washing performance of laundry rinsed with hard water. The hard water leaving the filtration unit (4) is made use of, additional water is not received from the water mains (S) for the rinsing steps and water saving is provided.
In an embodiment of the present invention, the washing machine (1) comprises an inlet opening (16) disposed on the tub (2) wherefrom the rinsing water line (13) is connected to the tub (2) (Figure 1, Figure 2).
In another embodiment of the present invention, the washing machine (1) comprises the soft water line (5), one end connected to the filtration unit (4), the other end connected to the inlet opening (16) by joining with the rinsing water line (13), thus transferring the soft water received from the filtration unit (4) to the tub (2) independently from the detergent dispenser (6) (Figure 2).
In this embodiment, the soft water line (5) and the rinsing water line (13) are joined on the inlet opening (16), in the main washing steps the soft water received from the soft water line (5) and in the rinsing steps the hard water received from the rinsing water line (13) is transferred to the tub (2). The first water inlet valve (3) is connected to the reservoir (9), the second water inlet valve (103) to the detergent dispenser (6), at the start of the washing program, first the second water inlet valve (103) is opened by the control unit (8) to receive water into the detergent dispenser (6) sufficient enough for flushing the detergents, for example 3 – 5 liters and the cleaning agents in the detergent dispenser (6) are flushed with the small amount of water received from outside and transferred into the tub (2). Afterwards, the second water inlet valve (103) is closed by the control unit (8), the first water inlet valve (3) is opened and water is received into the reservoir (9) for softening, the received water is softened in the filtration unit (4) and is transferred directly to the tub (2) by means of the soft water line (5) and the inlet opening (16), to be used in the main washing step. In the rinsing steps, similarly the hard water collected in the reservoir (9) is transferred directly to the tub (2) by means of the rinsing water line (13) and the inlet opening (16).
In another embodiment of the present invention, one end of the soft water line (5) is connected to the filtration unit (4) and the other end to the detergent dispenser (6). The water received into the reservoir (9) from the first water inlet valve (3) and removed of its hardness in the filtration unit (4), is transferred to the detergent dispenser (6) through the soft water line (5) to flush the detergents and then transferred to the tub (2) from there (Figure 3).
In another embodiment of the present invention, the washing machine (1) comprises a soft water pump (15), situated on the soft water line (5) between the filtration unit (4) and the detergent dispenser (6), which provides the soft water leaving the filtration unit (4) to be pressurized and transferred to the detergent dispenser (6). The soft water pump (15) pressurizes the water flowing from the soft water line (5) to the detergent dispenser (6), thereby providing the cleaning agents in the detergent dispenser (6) to be effectively flushed (Figure 4).
In another embodiment of the present invention, the washing machine (1) comprises the rinsing water line (13), whereof one end is connected to the reservoir (9) and the other end to the detergent dispenser (6). In this embodiment, the existing detergent dispenser (6) pathway is used for transferring hard water to the tub (2) and utilization of a separate pathway is not deemed necessary (Figure 3).
In the washing machine (1) of the present invention, the soft water leaving the filtration unit (4), having a cross-flow type nanofilter (NF) and functioning as water softening device, is used in the main washing steps with detergent, the hard water leaving the filtration unit (4) is utilized in the rinsing steps wherein detergent is not used. Receiving additional water from the water mains (S) is not necessary for the laundry rinsing activities and water saving is provided.
It is to be understood that the present invention is not limited by the embodiments disclosed above and a person skilled in the art can easily introduce different embodiments. These should be considered within the scope of the protection postulated by the claims of the present invention.

Claims

A washing machine (1) comprising a tub (2), at least one water inlet valve (3, 103) that provides water intake into the tub (2) from the water mains (S), a cross-flow type filtration unit (4), passing water through a nanofilter (NF) thus providing the removal of the hardness of water, a soft water line (5) that provides the water removed of its hardness in the filtration unit (4) to be transferred to the tub (2), a detergent dispenser (6), a control unit (8), a reservoir (9) connected to the first water inlet valve (3) and open to atmospheric pressure, a supply line (10) that provides circulation of water between the reservoir (9) and the filtration unit (4) and transfers water from the reservoir (9) to the filtration unit (4), a return conduit (11) that provides the transfer of the hard water running down from the nanofilter (NF) by flowing together with the substances trapped on the surface of the nanofilter (NF) in the filtration unit (4) to the reservoir (9) and a circulation pump (12) disposed on the supply line (10), providing the circulation of the water between the reservoir (9) and the filtration unit (4),

characterized in that

- a rinsing water line (13) for transferring hard water from the reservoir (9) to the tub (2),

- a water outlet valve (14) located on the rinsing water line (13) and

- the control unit (8) for opening the water outlet valve (14) in the laundry rinsing steps and providing the hard water collected in the reservoir (9) to be transferred to the tub (2).
A washing machine (1) as in Claim 1, characterized in that an inlet opening (16) disposed on the tub (2) wherefrom the rinsing water line (13) is connected to the tub (2).
A washing machine (1) as in Claim 2, characterized in that the soft water line (5), one end connected to the filtration unit (4), the other end connected to the inlet opening (16) by joining with the rinsing water line (13).
A washing machine (1) as in any one of the above Claims, characterized in that

- the first water inlet valve (3) connected to the reservoir (9),

- the second water inlet valve (103) connected to the detergent dispenser (6), and

- the control unit (8) for opening the second water inlet valve (103) firstly and providing water to be received into the detergent dispenser (6) and for opening the first water inlet valve (3) secondly and providing water to be received into the reservoir (9), at the start of the washing program.
A washing machine (1) as in Claim 1, characterized in that the soft water line (5), one end connected to the filtration unit (4), and the other end connected to the inlet opening (16).
A washing machine (1) as in Claim 5, characterized in that a soft water pump (15), situated on the soft water line (5) which provides the soft water leaving the filtration unit (4) and transferred to the detergent dispenser (6) under pressure.
A washing machine (1) as in Claim 5 or 6, characterized in that the rinsing water line (13), one end connected to the reservoir (9), and the other end connected to the detergent dispenser (6).