EP2981643A1

EP2981643A1 - Improved efficiency wash cycle for washing machine

Info

Publication number: EP2981643A1
Application number: EP13716755.7A
Authority: EP
Inventors: Cemal Murat Dora; Omer Dogan; Ilkan Erdem
Original assignee: Arcelik AS
Current assignee: Arcelik AS
Priority date: 2013-04-04
Filing date: 2013-04-04
Publication date: 2016-02-10
Anticipated expiration: 2033-04-04
Also published as: EP2981643B1; AU2013385216B2; AU2013385216A1; WO2014161579A1

Abstract

The present invention pertains to a washing machine (1) comprising a rotary drum (3) in which cloth items are placeable, a water tub (2) in which the rotary drum (3) is rotatable, a motor (7) providing the rotary drum (3) to be driven by means of a pulley mechanism (10), the latter disposed outside the tub (2), a circulation pump (4) in a circulation pipe (5) drawing wash water stored in the water tub (2) and delivering pressured water to a spray nozzle (8) via a nozzle water conduit (9), the spray nozzle (8) jetting the wash water from a front door (6) side above the rotary drum (3) toward the inner part of the same.

Description

IMPROVED EFFICIENCY WASH CYCLE FOR WASHING MACHINE

The present invention relates to a method for operating a washing machine having an improved washing performance.
Washing machines are generally classified as a top loading type washing machine or a front loading type washing machine. It is well-known that a front loading type washing machine contains a tub in a cabinet for receiving washing water and a drum rotatably mounted in the tub. Typically, wash water is received in the tub, and cloth items to be washed are placed in the drum. Cloth items are then lifted and dropped by lifters while the drum is rotated so that washing and rinsing process is carried out.
The washing machine of the above type further incorporates a pump unit for circulating washing water in the lower part of the tub, said pump unit conveying washing water to an upper part of the tub such that a more effcient washing angle can be obtained by means of a nozzle whereby water jets from the upper part of the tub are delivered.
It is to be noted that 20 % of total household water consumption originate from washing machines. To address this phenomenon, manufacturers design and implement various arrangements in need of improving water consumption profile of such machines. As modern washing programs more and more utilize less wash water, a more efficient wash cycle is considered as a decisive factor in this regard.
Among others, a prior art publication in the technical field of the invention may be referred to as US2008189875, which attempts at improving washing performance by configuration of individual phases of the wetting process so as to adjust the same in respect of the quantity and specific absorbency of the laundry.
The method of the present invention provides homogenous mixing and adequate impregnation of every part of cloth items with discontinuous peaks. The wash water extracted from the laundry during a first rotational profile of the drum is recirculated toward the inner central region of the drum for impregnating the laundry amassed in the inner central region during a second rotational profile. Further, an enhanced mechanical effect is obtained by increasing contacting potentiality of each cloth item with other ones due to a continuous speed rate regime. Speed rate is determined such that the laundry is kept centrally while at the same time causing relative movement of cloth items in contact with each other. Further, instantaneous scattering of the laundry is also ensured on an occasional basis.
The present invention provides a method for operating a washing machine to obtain an improved washing or rinsing efficiency, which is provided by the characterizing features as defined in Claim 1.
Primary object of the present invention is to provide a method for operating a washing machine with improved washing or rinsing efficiency.
The present invention proposes a front loading washing machine with a drum in which cloth items are placeable and a water tub in which the rotary drum is rotatable. A motor conventionally provides that the drum is driven by means of a pulley mechanism disposed outside the tub.
A circulation pump is provided in a circulation pipe, which draws wash water stored in the water tub. Pressured water is supplied to a spray nozzle through a nozzle water conduit. In this way, the spray nozzle produce water jets targeting cloth items in the drum.
The spray nozzle jets wash water from a front door side above the rotary drum toward the inner region of the same. The method of the invention is performed such that the rotary drum is rotated at a first peak speed followed by a lower peak speed. Peak speeds are not maintained and as such they are temporary values. Each pair of the first and second peaks is repeated in alternating directions and the circulation pump is operated alongside.
A second step of water releasing is then performed in which the circulation pump is not operated and the motor is rotated at a speed of about 50-55 rpm in opposite directions in an alternating manner. The final step features a continuous speed rate of about 40-45 rpm in opposite direction in an alternating manner with infrequent peaks of 100 rpm in between.
Accompanying drawings are given solely for the purpose of exemplifying a method for operating a washing machine with improved washing or rinsing efficiency whose advantages over prior art were outlined above and will be explained in brief hereinafter.
The drawings are not meant to delimit the scope of protection as identified in the claims nor should they be referred to alone in an effort to interpret the scope identified in the claims without recourse to the technical disclosure in the description of the present invention.
Fig. 1 demonstrates a side cut-away view of a washing machine according to the present invention.
Fig. 2 demonstrates the drum’s rotation curve performed according to the first step of the wash cycle of the present invention.
Fig. 3 demonstrates the drum’s rotation curve performed according to the third step of the wash cycle of the present invention.
The following numerals are used in the detailed description:
Washing machine (1)
Water tub (2)
Rotary drum (3)
Circulation pump (4)
Circulation pipe (5)
Front door (6)
Motor (7)
Spray nozzle (8)
Nozzle water conduit (9)
Pulley mechanism (10)
The present invention proposes a washing machine designated generally by the numeral 1.
The present invention relates to a washing machine (1) comprising a rotary drum (3) rotated around the horizontal axis and wherein the laundry is placed. A water tub (2) in which said rotary drum (3) rotates is provided such that a motor (7) drives a rotary drum (3) by means of a pulley mechanism (10) disposed outside said water tub (2). The latter transmits rotational movement of the motor (7) to the rotary drum (3). The washing machine (1) conventionally comprises a discharge pump that discharges the wash water as stipulated by the washing process; a discharge conduit conveys the wash water accordingly.
According to the present invention, a circulation pump (4) placed in a circulation pipe (5) draws wash water stored in the water tub (2) and pressurizes the wash water flowing in a nozzle water conduit (9) for conveying it into the rotary drum (3). This mechanism allows the wash water stored in the water tub (2) to run through the nozzle water conduit (9) and to circulate to the rotary drum (3).
A motor is drivingly coupled to the circulation pump (4) which delivers pressured water to a spray nozzle (8) via the nozzle water conduit (9). A conventional drum-type washing machine jets the wash water from a front door (6) side toward the inner part of the rotary drum (3) through the spray nozzle (8) placed above the rotary drum (3) at the front door (6) side.
The wash cycle of the present invention comprises the steps of water retention and impregnating laundry with wash water, water release and main wash cycles. In the first step of water retention, wash water is received in the rotary drum (3), this phase typically taking about five minutes. Thereupon, the rotary drum (3) is rotated at a speed of about 100 rpm followed by lower peaks of about 50-55 rpm. The speed characteristic of the motor (7) in this water retention and impregnation step requires that a first peak of about 100 rpm is followed by a second lower peak of about 50-55 rpm. The motor (7) is operated such that its speed is changed and decreased immediately after the peak values are reached. In other words, it is not operated continuously at peak speeds.
The first peaks in this regime serves to the purpose of fixating the laundry to the rotary drum’s (3) lateral walls. On the other hand, the second lower peaks will help homogenous mixing of the laundry as cloth items will disengage from the rotary drum’s (3) wall surfaces at these speeds. Homogenous mixing is important as it enables impregnation of every part of cloth items with the wash water.
The wash water discharged by the discharge pump is recirculated into the rotary drum (3) by the circulation pump (4) through the spray nozzle (8). This provides that the wash water containing detergents extracted from the laundry during operation of the motor (7) around the first peaks is recirculated toward the inner central region of the rotary drum (3), hence impregnating the laundry that is made disengaged from the rotary drum (3) walls during speeds around the second lower peaks. During the water retention and impregnation step, the motor of the circulation pump (4) is continuously operated as long as the motor’s (7) shaft rotates the rotary drum (3).
Further, in the first step, the motor (7) is operated such that each pair of the first and second peaks is repeated in alternating directions. Overall, the first step is very effective in ensuring that a homogenous mixing as well as an improved water consumption performance is obtained.
According to the wash cycle of the present invention, following the water retention and impregnation step, water releasing step is performed such that the circulation pump (4) is stopped and the motor (7) is rotated at around 50-55 rpm in opposite directions in an alternating manner. In this step, a certain amount of the wash water is taken out of the rotary drum (3) by the discharge pump.
The final step of the wash cycle according to the present invention is the main wash cycle. The main purpose of this step is to enhance mechanical effect by increasing contacting potentiality of each cloth item with other cloth items as much as possible. This is accomplished by a motor (7) speed of 40-45 rpm, which is slightly lower than the lower peak value of the first step. Since the laundry is already homogenously mixed and adequately wet at this final stage, a regime with continuous speed rate, i.e. having no discrete peak values is adopted. Continuous speed rate regime is advantageous in that the laundry is more and more amassed in the inner central region of the rotary drum (3) rather than being adhered to lateral walls, accordingly enhancing mechanical contact among cloth items. The speed is even lower than the second lower peak value in the first step of the wash cycle because it is considered as an optimal speed value for keeping the laundry centrally while at the same time causing relative movement of cloth items in contact with each other. There still exist periodical peaks of around 100 rpm for instantaneous scattering of the laundry. Those are provided at infrequent intervals such that their frequency is substantially lower than that of the main 40-45 rpm curve, the curve having a speed profile alternating in opposite directions.
In a nutshell, the present invention proposes a washing machine (1) comprising a rotary drum (3) in which cloth items are placeable, a water tub (2) in which the rotary drum (3) is rotatable, a motor (7) providing the rotary drum (3) to be driven by means of a pulley mechanism (10), the latter disposed outside the tub (2). A circulation pump (4) in a circulation pipe (5) draws wash water stored in the water tub (2) and delivers pressured water to a spray nozzle (8) via a nozzle water conduit (9), the spray nozzle (8) jetting the wash water from a front door (6) side above the rotary drum (3) toward the inner part of the same.
The present invention provides that the laundry is first adhered to the rotary drum’s (3) lateral walls and then amassed in the inner central region thereof. This movement provides homogenous mixing and adequate impregnation of every part of cloth items with the wash water. The first step comprises a first and a second motor speed values in the form of discontinuous peaks. The wash water containing detergents extracted from the laundry during the first peaks is recirculated toward the inner central region of the rotary drum (3) for impregnating the laundry amassed in the inner central region during the second lower peaks. Further, in the third step which is the main wash cycle, an enhanced mechanical effect is obtained by increasing contacting potentiality of each cloth item with other ones due to a continuous speed rate regime. Speed rate is determined such that the laundry is kept centrally while at the same time causing relative movement of cloth items in contact with each other. Further, instantaneous scattering of the laundry is also ensured on an occasional basis.

Claims

A method for operating a washing machine (1), said washing machine (1) comprising a rotary drum (3) in which cloth items are placeable, a water tub (2) in which the rotary drum (3) is rotatable, a motor (7) providing the rotary drum (3) to be driven, a circulation pump (4) in a circulation pipe (5) drawing wash water stored in the water tub (2) and delivering pressured water to a spray nozzle (8) via a nozzle water conduit (9), the spray nozzle (8) jetting the wash water toward the inner central region of the rotary drum (3) characterized in that

the method comprises a first step of water retention and impregnating cloth items with wash water in which the rotary drum (3) is rotated at a first peak speed of about 100 rpm followed by a lower peak of about 50-55 rpm such that the rotary drum (3) speed is changed immediately after the peak values are reached and each pair of said first and second peaks is continuously repeated in alternating directions while the circulation pump (4) is operated provided that the rotary drum (3) is rotated,

the method comprises a second step of water releasing in which the circulation pump (4) is stopped and the motor (7) is rotated at about 50-55 rpm in opposite directions in an alternating manner and,

the method comprises a final step in which a continuous motor (7) speed rate of 40-45 rpm in opposite directions in an alternating manner is adopted with periodical peaks of about 100 rpm at infrequent intervals such that their frequency is substantially lower than that of the main 40-45 rpm curve.