Classifications

• • D—TEXTILES; PAPER
  • D06—TREATMENT OF TEXTILES OR THE LIKE; LAUNDERING; FLEXIBLE MATERIALS NOT OTHERWISE PROVIDED FOR
  • D06F—LAUNDERING, DRYING, IRONING, PRESSING OR FOLDING TEXTILE ARTICLES
  • D06F35/00—Washing machines, apparatus, or methods not otherwise provided for
  • D06F35/005—Methods for washing, rinsing or spin-drying
  • D06F35/006—Methods for washing, rinsing or spin-drying for washing or rinsing only

Definitions

• the present invention refers to a method for washing laundry and a laundry washing machine implementing such a method.
• modern laundry washing and, in some cases, drying machines usually comprise a washing tank, wherein a rotating basket is located, apt to contain the laundry.
• a liquid is supplied in the machine tank, which usually is made up of water with the possible addition of detergents and/or additives, and the basket is made rotating by means of an electric motor, properly controlled by a control system, allowing the selection of a desired washing program among a plurality of possible washing programs.
• the washing programs provided with the modern laundry washing machines can comprise one or more different treatment phases, like pre-washing, washing, rinsing, spinning, drying, which provide for different laundry treatment operations.
• a water-detergent solution is loaded in the machine tank, which is then usually heated by means of a suitable heater; the basket is then rotated at a relatively low speed, in the range of 35-60 rpm.
• the so obtained movement causes an at least the partial lifting of the laundry along the basket walls, until they fall again on the basket bottom, which is immersed in the liquid contained in the tank; said mechanical effect is possible because the gravity acceleration is greater then the centrifugal acceleration due to the basket rotation.
• the efficiency of said mechanical washing action is increased by alternating phases wherein the basket is rotated in a sense and phases wherein it is rotated in the opposite sense, and phases where the rotation is suppressed or stopped, of a certain duration.
• the basket rotation is interrupted and the liquid present in the tank is discharged out of the machine, by means of a suitable draining pump.
• the same technique described just now with reference to the washing and pre-washing phases is usually employed, i. e. exploiting the mechanical action generated by the rotation of the basket, also in opposite senses; in the case of the rinsing phases, however, for eliminating the detergent residues from the laundry, the tank is usually supplied with a water solution comprising a suitable additive, like a softening agent. Also in this case, at the end of each individual rinsing phase, the basket rotation is interrupted and the liquid present in the tank is drained out of the machine. At the end of each rinsing phase, at least a spinning stage is also usually provided, i. e. a phase where the basket is rotated at a high speed, e.g.
• the final spinning phase is instead performed after the last rinsing phase, always without supplying liquid in the tank and at a basket rotation speed which may reach 1.200 rpm.
• Such a phase has the purpose of eliminating from the laundry almost all the liquid left by the rinsing phases. For this reason, also the final spinning is performed while the draining pump is in operation.
• the last spinning phase may be followed by a drying phase, during which the basket is rotating for a generally long interval of time and at a relatively low speed, in presence of hot air circulating in the machine tank.
• the said disadvantage may be found, for instance, when washing particular delicate fabrics and/or being subject to dimensional variations, such as knitwear items and/or articles which may felt up (like wool, mohair, cashmere, alpaca, camel items etc.) and/or items made of fabrics which may slacken.
• knitwear items and/or articles which may felt up (like wool, mohair, cashmere, alpaca, camel items etc.) and/or items made of fabrics which may slacken.
• programs or washing cycles have been developed which are specifically directed to the delicate fabrics.
• the washing programs provided by the machines which make use of the said patent can however not yet fulfill the requirements which are demanded by the best known ruling authority of the wool field (International Wool Secretariat or IWS), in order to be certified as programs which can wash all the wool articles whereon the known label "hand washing” is reproduced.
• IWS International Wool Secretariat
• the said known laundry washing machines furthermore require a relatively long treatment time, and an important consumption of water and electric power, which possibly would be advisable to reduce.
• the present invention has the aim of indicating a new washing method, and a washing machine for implementing such a method, which allows for improving the performances which can be achieved by the known technique.
• a further aim of the present invention is that of indicating a method and/or a washing machine, which allows to reduce, using the same detergents and/or washing additives of the known technique, the water and/or electric power consumption, and/or the times being necessary for treating the said laundry items.
• Such aims are obtained, according to the present invention, by a laundry washing method and a laundry washing machine having the features of the attached claims, which shall be considered as an integral part of the present description.
• a washing cycle implementing the teachings of the present invention may comprise a washing stage, at least in part performed with heated water, and at least two rinsing stages performed for example with cold water, each one followed by at least a spinning stage.
• the washing stage LB comprises at least three steps, which are indicated in the figure with LI, L2 and L3, with a basket rotation equal to or greater than the lowest speed allowing the laundry items to be kept adherent to the basket walls.
• the items to be washed are brought temporarily in contact with and/or at least partially immersed into the liquid and/or the foam present in the bottom of the tank and the basket.
• CL indicates an initial water supply from the water mains, of about six-seven liters, necessary for performing the washing stage LB; such a supplying is made according to known ways.
• the basket is made to rotate until it reaches the speed of about 90 rpm, which is just a speed sufficient to keep the laundry items adherent to the basket walls; such a speed is maintained during the step indicated with LI for about 2 minutes.
• the items to be washed are brought temporarily in contact with and/or at least partially immersed into the liquid and/or the foam present in the bottom of the tank and the basket, at each basket rotation.
• the rotation is stopped and the washing stage goes on with a step LI' of pause of the movement of laundry items; during such a pause step the laundry lies on the bottom of the basket.
• Step LI' the liquid present in the tank is heated up to the washing temperature, in the order of about 30°-40°C, by means of a common heater under the control of the machine control system.
• Step LI' which lasts about 5 minutes, is then followed by a basket rotation step L2 at a speed of about 90 rpm, analogous to the previous mentioned step LI ; however, it should be noticed that that the step L2 does not provide for any new water supply from the mains, but is performed with the liquid already present in the tank.
• the washing stage LB goes then on with a pause step L2', wherein the basket rotation is stopped, analogously to what has been previously said about the step LI', but without heating again the washing liquid.
• step L3 then follows, analogous to the preceding steps LI and L2, again without new water supply.
• the LB stage goes then on with a step L3', analogous to the preceding steps LI' and L2', again without new liquid heating.
• the control system activates the draining pump, in order to evacuate from the tank the liquid which has been used during the washing stage LB; the control system then provides for starting the basket rotation again, so as to bring it to a rotation speed of about 90 rpm.
• the washing stage LB is over, and the cycle goes on with the first rinsing stage, indicated with RSI .
• the machine control system provides for effecting a new water supply from the mains, indicated in the figure with CR, with the possible addition of a rinsing additive (like a softening means); the water quantity supplied into the tank is in this case of 9-10 liters; the loading CR is therefore made with the basket in movement.
• the rinsing stage RS 1 provides for a continue and unidirectional rotation of the basket, at the speed of about 90 rpm, said rotation lasting for about 2 minutes; the items to be rinsed are therefore brought temporarily and at least partially in contact with and/or immersed into the liquid and/or the foam present in the bottom of the tank and the basket, during each rotation, while being kept adherent to the basket walls.
• step RS 1 the control system provides for activating the draining pump in SR, in order to evacuate the rinsing liquid from the machine tank, without any interruptions in the in the rotation of the basket, and the spinning phase CI1 of the first rinsing stage is performed.
• the rotation speed is increased to about 400 rpm, during the step indicated with Cl and this speed is maintained for about 20 seconds.
• step C 1 due to the centrifugal force, the laundry items are strongly pushed against the basket sides, and kept there, so as to obtain a partial elimination of the liquid which soaked the laundry during the preceding stage; it should be noticed that during the step Cl the draining pump is operating.
• the basket rotation speed is reduced to about 90 rpm, for executing the step indicated with C2, which provides for a continue and unidirectional rotation of the basket, lasting about 20 seconds, so that the laundry items are steadily kept adherent to the basket sides.
• the basket rotation speed is increased, neither stopping the rotation, nor the pump operation, in order to effect the step C3, up to about 600 rpm; said speed is maintained for about 20 seconds.
• step C3 the basket rotation speed is again reduced to about 90 rpm, and the second rinsing stage RS2 is started, analogous to that previously indicated with RS 1 ; to said purpose, the machine control system provides for stopping the draining pump and enabling a new water supply step CR of about 9-10 liters from the mains.
• the second rinsing stage RS2 is followed by the relevant spinning stage CI2, inclusive of steps Cl, C2 and C3, performed with the draining pump in operation, as shown in SR and as already described with reference to stage CI1.
• the third rinsing stage RS3 then follows, inclusive of the relevant water supply CR, substantially analogous to those previously indicated with RSI and RS2.
• Such third rinsing stage RS3 is followed by the relevant spinning stage CI3, analogous to those previously indicated with CI1 and CI2, and inclusive of the corresponding steps Cl, C2 and C3 with draining pump in operation.
• the fourth rinsing stage RS4 follows, inclusive of the relevant water supply CR, substantially analogous to those previously indicated with RSI, RS2 and RS3.
• Such a fourth rinsing stage RS4 is finally followed by the relevant spinning stage CI4, analogous to those previously indicated with CI1 , CI2 and CI3, and inclusive of the corresponding steps Cl, C2 and C3 with draining pump operation.
• the washing cycle is over, or may be continued with a possible drying stage, realized according to the known ways.
• a series of at least two consecutive rinsing stages is performed, without stopping the basket rotation, and in particular keeping it constantly rotating at an angular speed equal to or greater than the lowest speed which allows the laundry items to be kept adherent to the basket walls.
• the basket rotation sense is never reversed, and the liquid supply and drain operations are made while the basket is in movement, namely remaining constantly at an angular speed equal to or greater than the lowest speed which allows the laundry items to be kept adherent to the basket walls.
• Detergent used 70 g. of liquid detergent (Perlana®) Number of cycles: 20
• Cycle duration 60 minutes 40 minutes (*)assessed according to the Cycle Felting Severity (C.S.F.) index, as percentage of average felting, obtained measuring the dimensional shrinking of the washed standard wool sample, after the 20 washing cycles.
• C.S.F. Cycle Felting Severity
• the above table shows immediately the improvements introduced by the invention in respect of the nevertheless valuable technique described in IT-B-1.230.903.
• the cycle according to the invention allows, in respect of the known art, a reduction of the felting value of about 65%, a water consumption reduction of more than 45%, a power consumption reduction of more than 38% and a washing time reduction of more than 30%.
• the method and/or the washing machine according to the present invention allows, in respect of the known technique, an important reduction of the damaging of some types of articles to be washed by means of a domestic laundry washing machine, particularly articles which are subject to dimensional variations, like knitwear items, and/or items made of fabrics which may shrink or felt (as wool, mohair, cashmere, alpaca, camel, etc.) and/or which may slacken.
• a substantial advantage of the invention is that of fulfilling the International Wool Secretariat requirements in respect of the possibility of washing, by means of a domestic laundry washing machine, all the wool articles that traditionally should be hand washed.
• said requirements foresee a felting value, after 20 washing cycles i. e. a number of washing cycles considered as representative of the average life of an article), which is less than 15% C.S.F.
• the method and/or the washing machine according to the present invention allows, even with the use of an equal quantity of detergent and/or washing additives as with the known technique, a drastic reduction of the water and electric power consumption. The same is true for the washing time of the articles, with a great advantage for the lasting life of the same.
• the invention is easy to implement on domestic laundry washing and/or drying machines, either of the type comprising an electronic (with micro-controller) or an electromechanical programmer.
• the control system of the machine provides for an electronic module, suitably controlled by the programmer for managing the basket moving stages.
• the above said speed values can vary, depending upon the washing basket radius. It should be pointed out that, in any case, in general terms, the basket speeds during the rinsing stages RS1-RS4 and the steps C2, should preferably be comprised between 80 and 240 rpm. Only as an indication, the speeds of the steps Cl and
• C3 could be between 300 and 1.200 rpm.
• the first foreseen rinsing stage starts in this way at a moment when the basket is already rotating at an angular speed at least equal to the lowest speed allowing the laundry items to be kept adherent to the basket walls or, in other words, during the time interval between the end of the stage immediately preceding the first rinsing stage and the beginning of the latter, the basket is constantly kept rotating at an angular speed at least equal to the lowest speed allowing the laundry items to be kept adherent to the basket walls.
• the cycle according to this proposed variant of the invention has allowed for the reaching of a felting level of 8,50 C.S.F. with a total treatment time of about 40 minutes, a water consumption of about 33 liters and a power consumption of about 0,15 kWh.
• the duration of the heating steps of the washing liquid or the supply steps from the mains depends, at least in part, on the time necessary to reach the desired liquid temperature, or the liquid level in the tank, which are measured by means of suitable known sensors.

Landscapes

• Engineering & Computer Science (AREA)
• Textile Engineering (AREA)
• Control Of Washing Machine And Dryer (AREA)
• Treatment Of Fiber Materials (AREA)
• Detergent Compositions (AREA)
• Accessory Of Washing/Drying Machine, Commercial Washing/Drying Machine, Other Washing/Drying Machine (AREA)
• Detail Structures Of Washing Machines And Dryers (AREA)

Applications Claiming Priority (3)

Publications (3)

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ID=11417940

Family Applications (1)

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Family Cites Families (5)

• 1999
  • 1999-07-05 IT IT1999TO000580A patent/IT1308788B1/it active
• 2000
  • 2000-07-04 AT AT00942308T patent/ATE250687T1/de not_active IP Right Cessation
  • 2000-07-04 AU AU57001/00A patent/AU5700100A/en not_active Abandoned
  • 2000-07-04 ES ES00942308T patent/ES2206261T5/es not_active Expired - Lifetime
  • 2000-07-04 EP EP00942308A patent/EP1208260B2/fr not_active Expired - Lifetime
  • 2000-07-04 WO PCT/IB2000/000903 patent/WO2001002639A1/fr active IP Right Grant
  • 2000-07-04 DE DE60005538T patent/DE60005538T3/de not_active Expired - Lifetime
  • 2000-07-04 DK DK00942308T patent/DK1208260T4/da active
  • 2000-07-04 PT PT00942308T patent/PT1208260E/pt unknown

Non-Patent Citations (1)

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