WO2008012354A1

WO2008012354A1 - A washing machine

Info

Publication number: WO2008012354A1
Application number: PCT/EP2007/057743
Authority: WO
Inventors: Hakan Tatar
Original assignee: Arcelik Anonim Sirketi
Priority date: 2006-07-28
Filing date: 2007-07-27
Publication date: 2008-01-31
Also published as: TR200900547T1

Abstract

The present invention relates to a washing machine (1) wherein the excessive foam formed in the washing process between the tub (3) and the drum (2) particularly at the rear region of the tub (3) is effectively removed.

Description

A WASHING MACHINE

[0001] The present invention relates to a washing machine wherein the increase of foaming is prevented during the washing processes.

[0002] In washing machines, excessive foaming can result when more than the required amount of detergent is used or when the detergent used has an extra foaming feature. This foam formation in the tub adversely affects the rinsing performance of the washing machine and results in residual detergent on the laundry at the end of the washing cycles. Detergent residue is detrimental to health and also gives the impression that the washing machine has not performed a complete washing. Furthermore, excessive foaming reaches the detergent dispenser through the tub water inlet and can overflow out of the washing machine from there. On the other hand, the accumulation of the foam in the space between the tub and the drum and resisting against the motion of the drum during spin-drying can s ometimes prevent the machine from reaching the desired spin acceleration. Various methods are used such as spraying water on the foam, slowing down drum rotational speed or discharging the foam in order to avoid the above mentioned problems.

[0003] In the European patent document no. EP0724036, the rotational speed of the drum is reduced, the water intake amount in the rinsing phase is increased and the user is warned in order to prevent excessive foaming.

[0004] In the United States of America patent document no. US2001052249, water is sprayed on the foam in a washing machine.

[0005] In the Japanese patent application no. JP2005013577, water is delivered over the tub with a shower-like mechanism.

[0006] However, in state of the art implementations of foam dousing with water, the water received into the tub is distributed either equally to the front and rear of the tub or most of it to the front side of the tub since the water inlet orifice is closer to the front. Consequently, the foam collected at the rear region of the tub cannot be adequately doused.

[0007] The foam that collects between the tub and the drum in the vicinity of the rear wall of the tub results in damaging of the machine and also reducing the efficiency by hampering the rotation of the drum during washing and spin-drying processes.

[0008] The object of the present invention is to design a washing machine wherein the excessive foam formed particularly at the rear region of the tub in the washing process is effectively removed.

[0009] The washing machine designed to fulfill the objectives of the present invention is explicated in the claims.

[0010] In the washing machine of the present invention, the foam formed in the tub is doused by spraying water in between the tub and the drum. A water distributor between the tub and the drum is utilized for effectively dousing the excessive foam accumulated at the rear side of the tub, having an orifice that extends into the tub with a cross-section area at the rear of the tub greater than the cross-section area at the front side such that a greater amount of the water sprayed into the tub is delivered between the drum and the tub, to the vicinity of the tub rear wall. Consequently, even though there is a difference in the amount of foam at the rear and front of the tub, the foam in the entirety of the tub is effectively doused by distributing the water delivered into the tub proportional to the foam amount.

[0011] In an embodiment of the present invention, the utilized water distributor comprises channel(s) formed on the tub that gets wider from the front towards the back. In this embodiment, water with a greater flow rate is delivered to the rear side of tub by means of the variable geometry of the water distributor, effectively dousing the excessive foam collected thereat.

[0012] In another embodiment of the present invention, water is received into the tub from more than one place. In this embodiment, the water distributor comprises hole(s) with a number and/or size allowing a greater amount of water to pass to the rear region of the tub than the front and/or the middle regions.

[0013] In an embodiment of the present invention, a foam sensor is used for detecting the formation of excessive foaming in the tub. In a version of this embodiment, the washing machine comprises a control unit that evaluates the measurements taken by the foam sensor and controls the water delivery or exit to the water distributor based on this evaluation. [0014] The washing machine designed to fulfill the object of the present invention is illustrated in the attached figures, where: [0015] Figure 1 - is the sideways schematic view of an embodiment of the present invention. [0016] Figure 2 - is the schematic view of a water distributor used in another embodiment of the present invention. [0017] Figure 3 - is the schematic view of another water distributor used in another embodiment of the present invention. [0018] Figure 4 - is the schematic view of another water distributor used in yet another embodiment of the present invention. [0019] The elements illustrated in the figures are numbered as follows:

1. Washing machine

2. Drum

3. Tub

4. Water distributor

5. Inlet conduit

6. Circulation pump

[0020] The washing machine (1) comprises a drum (2) wherein the laundry is emplaced, a tub (3) inside which the drum (2) rotates, a water distributor (4) having an orifice that delivers water to the tub (3) with a cross-section area at the rear side of the tub (3) being greater than the cross-section area at the front side such that all or a greater amount of the wash water is delivered between the drum (2) and the tub (3) to the vicinity of the tub (3) rear wall for effectively dousing the excessive foaming accumulated at the rear side of the tub (3) (Figure 1).

[0021] In an embodiment of the present invention, the water distributor (4) comprises at least one channel the cross-section area of which the water distributor (4) widens gradually from the front towards the back. The cross-section areas of the water distributor (4) orifices allowing entrance of water into the tub (3) are greater at the back than the cross-section areas of the front ones. Accordingly, more water is received to the rear side of the tub (3) for effectively dousing the accumulated excessive foam at the rear side of the tub (3). [0022] In an embodiment of the present invention, the water distributor (4) comprises hole(s) with a number and/or size for allowing more water to be received into the rear side of the tub (3). In other words, the numbers and/or sizes of the holes on the water distributor (4) allowing entrance of water between the drum (2) and the tub (3) gradually increase from the back towards the front. (Figures 2-5).

[0023] The washing machine (1) furthermore comprises an inlet conduit (5) that delivers water to the water distributor (4).

[0024] During washing, the water received from the main supply can either be delivered directly or through the detergent dispenser to the inlet conduit (5) or it is also possible to reroute the water collected under the foam formed in the lower region of the tub (3) to the inlet conduit (5) for redelivering over the tub (3). The washing machine (1) comprises a circulation pump (6) for rerouting the water collected under the foam in the lower region of the tub (3) to the inlet conduit (5) from the tub (3).

[0025] In an embodiment of the present invention, the washing machine (1 ) comprises a foam sensor that detects the formation of excessive foaming. In this embodiment, the washing machine (1) comprises a control unit that controls the delivery and exit of water to the water distributor (4) depending on the data determined by the sensor.

[0026] By means of the washing machine (1 ) of the present invention, the overflowing of the foam that may occur during spin-drying is prevented by effectively dousing the foaming formed in the tub (3) and the rinsing performance is enhanced. Furthermore, residual detergent streaks remaining on the laundry at the end of the washing is prevented.

Claims

1. A washing machine (1 ) comprising a drum (2) wherein the laundry is emplaced, a tub (3) inside which the drum (2) rotates, and characterized by a water distributor (4) having an orifice that delivers water to the tub (3) with a cross-section area at the rear side of the tub (3) that is greater than the cross-section area at the front side such that all or a greater amount of the wash water is delivered between the drum (2) and the tub (3) to the vicinity of the rear wall for dousing the excessive foaming accumulated at the rear side of the tub (3)

2. A washing machine (1 ) as in Claim 1 , characterized by a water distributor (4) comprising at least one channel formed on the tub (3) with a cross-section area that gradually widens from the front towards the back.

3. A washing machine (1 ) as in Claim 1 , characterized by a water distributor (4) comprising hole(s) having a number and/or size that allows a greater amount of water to be received into the rear side of the tub (3).

4. A washing machine (1) as in any one of the above claims, characterized by an inlet conduit (5) that delivers water to the water distributor (4).

5. A washing machine (1) as in Claim 4, characterized by an inlet conduit (5) to which the water received from the main supply can either be delivered directly or by passing through the detergent dispenser.

6. A washing machine (1) as in any one of the Claims 1 to 4, characterized by a circulation pump (6) for rerouting the water collected under the foam formed in the lower region of the tub (3) to the inlet conduit (5) to be redelivered over the tub (3).

7. A washing machine (1) as in any one of the above claims, characterized by a foam sensor that detects the formation of excessive foam and a control unit that controls the delivery and exit of water to the water distributor (4) depending on the data determined by the sensor.