EP0094357A1 - Machine à laver et procédé de régénération de la résine - Google Patents

Machine à laver et procédé de régénération de la résine Download PDF

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Publication number
EP0094357A1
EP0094357A1 EP83830089A EP83830089A EP0094357A1 EP 0094357 A1 EP0094357 A1 EP 0094357A1 EP 83830089 A EP83830089 A EP 83830089A EP 83830089 A EP83830089 A EP 83830089A EP 0094357 A1 EP0094357 A1 EP 0094357A1
Authority
EP
European Patent Office
Prior art keywords
resin
perfected
water
washing machine
resin regenerating
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Granted
Application number
EP83830089A
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German (de)
English (en)
Other versions
EP0094357B1 (fr
Inventor
Marcello Premoli
Giuseppe Nerozzi
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Indesit Industria Elettrodomestici Italiana SpA
Original Assignee
Indesit Industria Elettrodomestici Italiana SpA
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Indesit Industria Elettrodomestici Italiana SpA filed Critical Indesit Industria Elettrodomestici Italiana SpA
Publication of EP0094357A1 publication Critical patent/EP0094357A1/fr
Application granted granted Critical
Publication of EP0094357B1 publication Critical patent/EP0094357B1/fr
Expired legal-status Critical Current

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    • A—HUMAN NECESSITIES
    • A47—FURNITURE; DOMESTIC ARTICLES OR APPLIANCES; COFFEE MILLS; SPICE MILLS; SUCTION CLEANERS IN GENERAL
    • A47L—DOMESTIC WASHING OR CLEANING; SUCTION CLEANERS IN GENERAL
    • A47L15/00—Washing or rinsing machines for crockery or tableware
    • A47L15/42—Details
    • A47L15/4229—Water softening arrangements

Definitions

  • the present invention relates to a washing machine, with a perfected resin regenerating process, comprising a wash chamber, washing components and components for softening the water supplied from the mains.
  • the said softeners consist essentially of a container filled with sulphonated resin granules through which the hard water is sent for softening.
  • the said resin reacts strongly with the calcium (Ca) and magnesium (Mg) ions in the water they come into contact with, thus reducing its hardness.
  • dishwashing-machines are usually fitted with a three-way electrovalve, a first for letting in hard water in certain wash stages, a second for letting in softened water in other wash stages and a third for letting in the water for regenerating the resin.
  • the resin is regenerated during the dish-drying cycle and washed at the start of the next wash cycle.
  • the amount of hardness removed by a specific type of softner is strictly proportional to the amount of resin in the softener itself. Consequently, either the capacity of the latter is overestimated (an obvious waste both in terms of manufacturing and running expenses) or a limit placed on the hardness of the water that can be employed (which obviously limits the scope of the machine itself).
  • the softening capacity of the resin that is, the percentage of hardness removed, depends on the volume of resin inside the softener, on the volume of water and the speed at which it is loaded and the efficiency with which the resin is regenerated.
  • the resin is essentially regenerated in two stages : one dynamic (when the NaCl solution is poured into the resin container) and one static (when the said solution has settled inside the said container). Most of the regeneration process is performed in the dynamic stage, whereas static regeneration becomes gradually less effective as time goes by, so much so that, after two hours, it has practically no effect whatsoever.
  • the aim of the present invention is therefore to overcome the above drawbacks by providing a washing machine with a perfected resin regenerating process which, by improving regeneration efficiency, provides essentially for using any type of hard water without having to overestimate the capacity of the softener; which removes the strict relationship between the amount of resin contained inside the softener and the amount of hardness removed, by adapting regenerating efficiency to the amount of water actually employed in a given wash cycle; which, in the case of medium-high hard water, provides for softening all the water needed for an entire wash cycle; and which provides for using a two-way electrovalve and, consequently, supply pipes for only two hydraulic circuits.
  • Further aims of the present invention are to reduce both material and manufacturing costs of the dishwashing-machine and to keep down running costs even in the case of very hard water.
  • the present invention relates to a washing machine, with a perfected resin regenerating process, comprising a wash chamber, washing components and components for softening the water supplied from the mains, characterised by the fact that it comprises means which, without increasing the capacity of the softening components, ensure greater resin regenerating efficiency to the extent that the softening capacity of the softening components is such as to provide essentially for washing with any type of hard water.
  • the amount of water processed (Q) is expressed in litres on the Y axis and the percentage of residual hardness in the processed water coming from the softener shown on the X axis.
  • the softening efficiency curves marked “a” refer to fully regenerated resin, whereas "b” and “c” are two of a family of softening efficiency curves relating to resin only partially regenerated and depending on resin regenerating efficiency.
  • Fig. la shows the graph of an ideal softener operating under ideal conditions, i.e. a very high cylindrical softener with a very small base, through which flows 50 Vol/Vol/h of water (i.e. the volume of water flowing through it in an hour is equivalent to 50 times the volume of resin it contains).
  • Curves "b” and “c” relative to partially regenerated resin and which follow the same trend as “a” show how the quantity of water that can be softened falls alongside the fall in resin regenerating efficiency.
  • Fig. 1b relates to the same ideal softener shown in Fig. 1a but with 700 Vol/Vol/h of water flowing through it (i.e. the volume of water flowing through it in one hour is equivalent to 700 times the volume of resin it contains). This is the amount of water with which current dishwashing-machines are usually filled.
  • Curve "a” shows how a certain amount of residual hardness is left even when very small quantities of water are processed and how the relative curve is less steep than the corresponding "a" curve in Fig, 1a.
  • Fig. 1c relates to the softener used in the present invention which consists of a cylindrical container with a base diameter to height ratio of around 1:2 and through which flows 700 Vol/Vol/h of water.
  • the amount of processable water is even higher than that processable using the Fig. 1b softener.
  • Fig. 2 shows a wash cycle on a known type of dishwashing-machine : number 1 indicates an intensive wash cycle, 2 a normal wash cycle, 3 the hot washing stage, 4 the first cold rinse, 5 the second cold rinse, 6 the third hot rinse, 7 the drying stage, letter "A” the resin regenerating stage, "B” the resin wash stage, "C” soft water fill and “D” hard water fill.
  • the wash cycle in Fig. 2a shows how the resin regenerating stage starts during the dish drying stage and continues until the next washing operation starts, how the resin wash stage is performed at the start of the next normal washing operation and how softened water is only loaded three times.
  • Dishwashing-machines using the said wash cycle and a softener containing 0.4 1 of ion-exchange resin are capable of softening 30 litres of water with a maximum hardness of 45°F.
  • Static regeneration of the resin goes on for hours but, if a new washing operation is started straight after the end of the previous one, static regeneration only lasts the length of the drying stage (about 10 minutes) which is not long enough to ensure all the loaded water is softened properly. In other words, it could happen that, when soft water is loaded for the third time (for hot rinsing), the resin is exhausted and hard water would be loaded just when it should not be, i.e. just before drying in which stage the calcium (Ca) and magnesium (Mg) salts would cling to the dishes thus jeopardizing the success of the wash.
  • Ca calcium
  • Mg magnesium
  • Fig. 2b shows a wash cycle on a diswashing-machine using a first arrangement of the perfected resin regenerating process covered by the present invention; the cycles and wash stages common to Fig. 2a are shown using the same letters and numbers.
  • the resin is washed at the end of the drying stage, when water is loaded during cold prewash 2 and when water is loaded during first cold rinse 4.
  • a first additional regenerating stage is performed, which consists in sending 0.1 1 of NaCl solution to the softener for 20", followed by a pause which lasts throughout hot wash 3 (about 20').
  • the said first additional regenerating stage is highly effective in that it combines dynamic regenerating efficiency with static regeneration lasting 20' which also provides a large contribution.
  • a second additional regenerating stage is performed straight after water is loaded for hot prewash 1, which also consists in sending 0.1 of NaCl solution to the softener for 20", followed by a pause lasting throughout hot prewash 1 (about 20').
  • the said second additional regenerating stage is also highly effective for the same reasons mentioned above.
  • water is loaded for cold prewash 2 which, passing through the softener, also washes the resin.
  • the water containing the products of resin regeneration goes into the wash tub but, as explained previously, no damage is done to the metal parts in the tub for the reasons already given.
  • the extent to which the resin is regenerated is proportional to the number of times water is loaded and, therefore, to the amount of water used for washing the dishes.
  • Figure 2c shows a wash cycle on a diswashing- machine using a second arrangement of the perfected resin regenerating process covered by the present invention. Cycles and wash stages common to Figs 2a and 2b are marked using the same letters and numbers.
  • the cycle shown in Fig. 2c can be said to be a combination of those shown in Figs 2a and 2b, that is, in certain stages of the wash cycle, the machine is loaded with hard water, whereas in others it is loaded with soft water as in the Fig. 2a cycle.
  • the additional regenerating stages are also performed as in the Fig. 2b cycle. Resin regeneration is therefore strengthened, as in the Fig. 2b cycle, whereas the softened water requirement is that of the Fig. 2a cycle, i.e. about 301. Consequently, a dishwashing-machine using this second arrangement of the perfected resin regenerating process and a softener containing 0.4 1 of ion-exchange resin is capable of softening water with around 70°F hardness.
  • the said second arrangement needs a three-way electrovalve but this extra cost is compensated by the possibility of softening very hard water which otherwise could not be used in a dishwashing-machine.
  • the significance of this second arrangement will become clearer if we consider that 70°F is practically the maximum hardness allowed in water employed in dishwashing-machines.
  • dishwashing-machines in particular and washing machines in general can be operated with practically any type of hard water.
  • the timer controlling operation of all the parts on the dishwashing-machine must be designed so as to control the first stage arrangement - water loading, softening, resin regeneration and wash - or the second.
  • Fig. 3 shows a diagram of the hydraulic circuit on a dishwashing-machine using the first arrangement of the perfected resin regenerating process covered by the present invention. It comprises a mains water inlet pipe 10 to which is connected a two-way (E and E 2 ) electrovalve 11.
  • the first way (E 1 ) on electrovalve 11 is connected to one end of pipe 12 the other end of which is connected to a first inlet on cylindrical softener 13 which contains ion-exchange resin granules of about 1 mm in diameter, not shown in the Figure.
  • the second way (E 2 ) of electrovalve 11 is connected to one end of pipe 14 the other end of which is connected to the inlet of container 15 filled with salt.
  • the outlet of salt container 15 is connected to one end of pipe 16 the other end of which is connected to a second inlet on softener 13.
  • the outlet of softener 13 is connected to one end of pipe 17 the other end of which is connected to the inlet of a wash tub 18 on a dishwashing-machine comprising a wash pump 19 and a water drain pipe 20.
  • the device shown in Fig. 3, controlled by a timer not shown in the Figure operates as follows:

Landscapes

  • Treatment Of Water By Ion Exchange (AREA)
EP83830089A 1982-05-07 1983-05-03 Machine à laver et procédé de régénération de la résine Expired EP0094357B1 (fr)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
IT67598/82A IT1156468B (it) 1982-05-07 1982-05-07 Macchina per lavare con procedimento perfezionato di rigenerazione delle resine
IT6759882 1982-05-07

Publications (2)

Publication Number Publication Date
EP0094357A1 true EP0094357A1 (fr) 1983-11-16
EP0094357B1 EP0094357B1 (fr) 1986-08-27

Family

ID=11303748

Family Applications (1)

Application Number Title Priority Date Filing Date
EP83830089A Expired EP0094357B1 (fr) 1982-05-07 1983-05-03 Machine à laver et procédé de régénération de la résine

Country Status (3)

Country Link
EP (1) EP0094357B1 (fr)
DE (1) DE3365580D1 (fr)
IT (1) IT1156468B (fr)

Cited By (12)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0405086A1 (fr) * 1989-06-29 1991-01-02 BOSCH-SIEMENS HAUSGERÄTE GmbH ProcédÀ© d'exploitation d'un lave-vaisselle commandé par un programmateur
DE4131791C1 (en) * 1991-09-24 1993-02-04 Bosch-Siemens Hausgeraete Gmbh, 8000 Muenchen, De Method for operating dishwasher - uses programmable water softening ion exchanger and regenerating water storage container
FR2699803A1 (fr) * 1992-12-30 1994-07-01 Esswein Sa Perfectionnement aux machines à laver utilisant de l'eau adoucie.
GB2321588A (en) * 1997-01-30 1998-08-05 Ferex Ltd Water softener control for washing machine
EP1085118A2 (fr) * 1999-09-20 2001-03-21 Hitachi, Ltd. Machine à laver
EP1114607A1 (fr) * 1999-12-03 2001-07-11 T & P S.p.A. Circuit hydraulique pour l'optimisation de la décalcification en particulier pour lave-vaiselle et procédé de commande correspondant
EP2366322A3 (fr) * 2010-03-18 2011-10-12 Electrolux Home Products Corporation N.V. Procédé de régénération de résine d'adoucissant de l'eau dans un lave-vaisselle
ITTO20130338A1 (it) * 2013-04-24 2014-10-25 Bitron Spa Sistema di alimentazione e trattamento di acqua per una macchina lavatrice, in particolare una macchina lavastoviglie
ITTO20130339A1 (it) * 2013-04-24 2014-10-25 Bitron Spa Sistema di alimentazione e trattamento di acqua per una macchina lavastoviglie
US9839945B2 (en) 2014-05-02 2017-12-12 Electrolux Home Products, Inc. Methods, systems, and apparatuses for performing a quick cycle in a dishwasher
US9936852B2 (en) 2010-03-18 2018-04-10 Electrolux Home Products Corporation N.V. Method for filling a wash tub of a dishwasher with water
CN111685679A (zh) * 2020-04-30 2020-09-22 浙江三花智能控制股份有限公司 洗碗机的控制方法

Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3148687A (en) * 1961-05-20 1964-09-15 Dosch Paul Article washing machine including a water softening arrangement
FR1467729A (fr) * 1965-02-12 1967-01-27 Constructa Werke Gmbh Commande de vanne électromagnétique d'un récipient à agent de régénération, de préférence destinée à une machine à laver la vaisselle
GB1182341A (en) * 1966-03-30 1970-02-25 Gen Electric An Automatic Washing Machine for Dishes, Clothes or the like
US3544371A (en) * 1968-03-25 1970-12-01 Miele & Cie Device for regenerating an ion exchanger,water softener in a dishwashing or other washing machine
FR2296395A1 (fr) * 1974-12-31 1976-07-30 Esswein Sa Machine a laver munie d'un adoucisseur d'eau
FR2325348A1 (fr) * 1975-09-24 1977-04-22 Zanussi A Spa Industrie Perfectionnement au procede de lavage de la vaisselle et machine domestique mettant en oeuvre le procede
FR2383259A1 (fr) * 1977-03-10 1978-10-06 Euro Hausgeraete Gmbh Dispositif de commande pour une machine a laver le linge ou la vaisselle

Patent Citations (7)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3148687A (en) * 1961-05-20 1964-09-15 Dosch Paul Article washing machine including a water softening arrangement
FR1467729A (fr) * 1965-02-12 1967-01-27 Constructa Werke Gmbh Commande de vanne électromagnétique d'un récipient à agent de régénération, de préférence destinée à une machine à laver la vaisselle
GB1182341A (en) * 1966-03-30 1970-02-25 Gen Electric An Automatic Washing Machine for Dishes, Clothes or the like
US3544371A (en) * 1968-03-25 1970-12-01 Miele & Cie Device for regenerating an ion exchanger,water softener in a dishwashing or other washing machine
FR2296395A1 (fr) * 1974-12-31 1976-07-30 Esswein Sa Machine a laver munie d'un adoucisseur d'eau
FR2325348A1 (fr) * 1975-09-24 1977-04-22 Zanussi A Spa Industrie Perfectionnement au procede de lavage de la vaisselle et machine domestique mettant en oeuvre le procede
FR2383259A1 (fr) * 1977-03-10 1978-10-06 Euro Hausgeraete Gmbh Dispositif de commande pour une machine a laver le linge ou la vaisselle

Cited By (18)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
EP0405086A1 (fr) * 1989-06-29 1991-01-02 BOSCH-SIEMENS HAUSGERÄTE GmbH ProcédÀ© d'exploitation d'un lave-vaisselle commandé par un programmateur
DE4131791C1 (en) * 1991-09-24 1993-02-04 Bosch-Siemens Hausgeraete Gmbh, 8000 Muenchen, De Method for operating dishwasher - uses programmable water softening ion exchanger and regenerating water storage container
FR2699803A1 (fr) * 1992-12-30 1994-07-01 Esswein Sa Perfectionnement aux machines à laver utilisant de l'eau adoucie.
EP0605288A1 (fr) * 1992-12-30 1994-07-06 Esswein S.A. Perfectionnement aux machines à laver utilisant de l'eau adoucie
GB2321588A (en) * 1997-01-30 1998-08-05 Ferex Ltd Water softener control for washing machine
GB2321588B (en) * 1997-01-30 2000-11-15 Ferex Ltd A washing machine
EP1085118A3 (fr) * 1999-09-20 2003-08-13 Hitachi, Ltd. Machine à laver
EP1085118A2 (fr) * 1999-09-20 2001-03-21 Hitachi, Ltd. Machine à laver
EP1114607A1 (fr) * 1999-12-03 2001-07-11 T & P S.p.A. Circuit hydraulique pour l'optimisation de la décalcification en particulier pour lave-vaiselle et procédé de commande correspondant
EP2366322A3 (fr) * 2010-03-18 2011-10-12 Electrolux Home Products Corporation N.V. Procédé de régénération de résine d'adoucissant de l'eau dans un lave-vaisselle
US9936852B2 (en) 2010-03-18 2018-04-10 Electrolux Home Products Corporation N.V. Method for filling a wash tub of a dishwasher with water
ITTO20130338A1 (it) * 2013-04-24 2014-10-25 Bitron Spa Sistema di alimentazione e trattamento di acqua per una macchina lavatrice, in particolare una macchina lavastoviglie
ITTO20130339A1 (it) * 2013-04-24 2014-10-25 Bitron Spa Sistema di alimentazione e trattamento di acqua per una macchina lavastoviglie
WO2014174451A1 (fr) * 2013-04-24 2014-10-30 Bitron S.P.A. Système d'amenée et de traitement d'eau pour une machine à laver, en particulier un lave-vaisselle
WO2014174452A1 (fr) * 2013-04-24 2014-10-30 Bitron S.P.A. Système d'alimentation et de traitement de l'eau pour un lave-vaisselle
CN105338873A (zh) * 2013-04-24 2016-02-17 毕勤股份有限公司 用于洗涤机、特别是洗碗机的用于供应和处理的水的系统
US9839945B2 (en) 2014-05-02 2017-12-12 Electrolux Home Products, Inc. Methods, systems, and apparatuses for performing a quick cycle in a dishwasher
CN111685679A (zh) * 2020-04-30 2020-09-22 浙江三花智能控制股份有限公司 洗碗机的控制方法

Also Published As

Publication number Publication date
EP0094357B1 (fr) 1986-08-27
DE3365580D1 (en) 1986-10-02
IT1156468B (it) 1987-02-04
IT8267598A0 (it) 1982-05-07

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